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Alternative Farming Systems Information Center of the National Agricultural Library
Agricultural Research Service, U.S. Department of Agriculture


Legumes in Crop Rotations
January 1990 - December 1993

 TITLE: Legumes in Crop Rotations
 AUTHOR:   Mary V. Gold
           Alternative Farming Systems Information Center
           National Agricultural Library
 PUBLICATION DATE:  June 1994
 SERIES: QB 94-38
 Updates QB 90-02 and QB 88-45
 NAL Call no.:   aZ5071.N3 no.94-38
 CONTACT:  Alternative Farming Systems Information Center
           National Agricultural Library
           Room 123, 10301 Baltimore Ave.
           Beltsville, MD  20705-2351
           Telephone:  (301) 504-6559
           http://afsic.nal.usda.gov

 
 ==============================================================
                                              ISSN:  1052-5378
 United States Department of Agriculture
 National Agricultural Library
 10301 Baltimore Blvd.
 Beltsville, Maryland  20705-2351
 
 
 Legumes in Crop Rotations
 January 1990 - December 1993
 
 
 Quick Bibliography Series:  QB 94-38
 Updates QB 90-02 and QB 88-45
 
 429 citations in English from AGRICOLA
 
 Mary V. Gold
 Alternative Farming Systems Information Center
 
  June 1994
 
 
 
 National Agricultural Library Cataloging Record:
 
 Gold, Mary V.
   Legumes in crop rotations : January 1990-December 1993.
   (Quick bibliography series ; 94-38)
   1. Crop rotation--Bibliography. 2. Legumes--Bibliography. I. Title.
 aZ5071.N3 no.94-38
 

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 AGRICOLA
 
 Citations in this bibliography were entered in the AGRICOLA database between
 January 1979 and the present.
 
 
Search AGRICOLA (http://agricola.nal.usda.gov) to update this Quick Bibliography. 
Use the search strategy and terms located below, plus the extensive AGRICOLA Help 
site to locate recent literature on your subject of interest.
 
 
 
 SAMPLE CITATIONS
 
 Citations in this bibliography are from the National Agricultural Library's
 AGRICOLA database.  An explanation of sample journal article, book, and
 audiovisual citations appears below.
 
 JOURNAL ARTICLE:
 
   Citation #                                     NAL Call No.
   Article title.
   Author.  Place of publication:  Publisher.  Journal Title.
   Date.  Volume (Issue).  Pages.  (NAL Call Number).
 
 Example:
   1                             NAL Call No.:  DNAL 389.8.SCH6
   Morrison, S.B.  Denver, Colo.:  American School Food Service
   Association.  School foodservice journal.  Sept 1987. v. 41
   (8). p.48-50. ill.
 
 BOOK:
 
   Citation #                                   NAL Call Number
   Title.
   Author.  Place of publication:  Publisher, date. Information
   on pagination, indices, or bibliographies.
 
 Example:
   1                        NAL Call No.:  DNAL RM218.K36 1987
   Exploring careers in dietetics and nutrition.
   Kane, June Kozak.  New York:  Rosen Pub. Group, 1987.
   Includes index.  xii, 133 p.: ill.; 22 cm.  Bibliography:
   p. 126.
 
 AUDIOVISUAL:
 
   Citation #                                  NAL Call Number
   Title.
   Author.  Place of publication:  Publisher, date.
   Supplemental information such as funding.  Media format
   (i.e., videocassette):  Description (sound, color, size).
 
 Example:
   1                    NAL Call No.: DNAL FNCTX364.A425 F&N AV
   All aboard the nutri-train.
   Mayo, Cynthia.  Richmond, Va.:  Richmond Public Schools,  1981.  NET funded. 
 Activity packet prepared by Cynthia
   Mayo.  1 videocassette (30 min.): sd., col.; 3/4 in. +
   activity packet.
 
 
 
 Legumes in Crop Rotations
 
 SEARCH STRATEGY
 
 
 Set     Description
 ===     ============
 
 S1.     ROTAT? OR (GREEN()MANURE?) OR (COVER()CROP?) OR  (CROP?(2N)SEQUENCE?)
         OR (LEY()FARM?) OR LEYS
 
 S2      LEGUM? OR ARACHIS OR PEANUT? OR GROUNDNUT? OR ASTRAGALUS OR CROTALARIA
         OR (GLYCINE MAX) OR SOYBEAN? OR SOYA? OR LUPIN? OR MEDICAGO OR ALFALFA
         OR MELIOTUS OR CLOVER OR MUCUNA OR BEAN OR BEANS OR PISUM OR PUERARIA
         OR SESBANIA OR TRIFOLIUM OR VICIA OR VIGNA OR CANAVALIA OR LATHYRUS OR
         LENS OR PEA OR PEAS OR PHASEOLUS OR AESCHYNOMENE OR ASTRAGALUS OR
         CALOPOGONIUM OR CENTROSEMA OR INDIGOFERA OR VETCH OR COWPEA? OR MEDIC
 
 S3      S1 AND S2
 
 S4      S3 NOT (ORCHARD? OR FOREST? OR PASTUR? OR GRAZ?)
 
 S5      S4 NOT (RNA OR TRNA OR MRNA OR DNA)
 
 S6      S5/ENGLISH
 
 S7      S6/1990-1993
 
 
 
 Legumes in Crop Rotations
 
 
 
 1                                                  NAL Call. No.: S544.3.N6N62
 1989 soybean on-farm test report.
 Dunphy, E.J.
 Raleigh, N.C. : The Service; 1991 Mar.
 AG - North Carolina Agricultural Extension Service, North Carolina State
 University v.): 29 p.; 1991 Mar.
 
 Language:  English
 
 Descriptors: North Carolina; Glycine max; Varieties; Rotations; Crop yield;
 Seed sources; Row spacing; Tillage; Repellents; Statistics; Variety trials
 
 
 2                                                   NAL Call. No.: 275.29 W27P
 1991 crop enterprise budgets: winter wheat-dry pea rotation -- Columbia County,
 Washington.
 Hinman, H.; Schirman, R.
 Pullman, Wash. : The Service; 1991 Aug.
 Extension bulletin - Washington State University, Cooperative Extension Service
 (1617): 19 p.; 1991 Aug.
 
 Language:  English
 
 Descriptors: Washington; Triticum aestivum; Rotations; Farm budgeting; Cost
 analysis; Pisum sativum
 
 
 3                                                  NAL Call. No.: S544.3.A2C47
 1992 peanut: insect, disease, nematode, and weed control recommendations.
 Auburn, Ala. : The Service; 1992 Feb.
 Circular ANR - Alabama Cooperative Extension Service, Auburn University (360):
 11 p.; 1992 Feb.  In Subseries: Integrated Pest Management.  Includes
 references.
 
 Language:  English
 
 Descriptors: Alabama; Arachis hypogaea; Insect control; Disease control;
 Nematode control; Weed control; Integrated pest management; Insects;
 Insecticides; Plant diseases; Nematoda; Fungicides; Nematicides; Herbicides;
 Weeds; Rotations; Record keeping
 
 
 4                                              NAL Call. No.: S650.83.M36 1991
 Accounting for nitrogen in nonequilibrium soil-crop systems.
 Schepers, J.S.; Mosier, A.R.
 Madison, Wis. : Soil Science Society of America; 1991.
 Managing nitrogen for groundwater quality and farm profitability : proceedings
 of a symposium. p. 125-138; 1991.  Includes references.
 
 Language:  English
 
 Descriptors: Nitrogen fertilizers; Crop management; Soil analysis;
 Mineralization; Irrigation water; Legumes; Rotations; Animal manures;
 Volatilization
 
 
 5                                                      NAL Call. No.: QH540.J6
 Accumulation of some metals by legumes and their extractability from acid mine
 spoils.
 Taylor, R.W.; Ibeabuci, I.O.; Sistani, K.R.; Shuford, J.W.
 Madison, Wis. : American Society of Agronomy; 1992 Apr.
 Journal of environmental quality v. 21 (2): p. 176-180; 1992 Apr.  Includes
 references.
 
 Language:  English
 
 Descriptors: Alabama; Glycine max; Vigna unguiculata; Trifolium incarnatum;
 Trifolium pratense; Lespedeza striata; Lespedeza cuneata; Heavy metals; Ion
 uptake; Coal mine spoil; Dry matter accumulation; Phytotoxicity; Extraction;
 Soil analysis; Soil acidity; Spoil heap soils; Reclamation
 
 Abstract:  A greenhouse study was conducted to investigate the growth (dry
 matter yield) of selected legume cover crops; phytoaccumulation of metals such
 as Zn, Ma, Pb, Cu, Ni, and Al; and extractability of heavy metals from three
 different Alabama acid mine spoils. The spoils were amended based on soil test
 recommended levels of N, P, K, Ca, and Mg prior to plant growth. Metals were
 extracted by three extractants (Mehlich 1, DTPA, and 0.1 M HCl) and values
 correlated with their accumulation by the selected legumes. Among the cover
 crops, kobe lespedeza [Lespedeza striata (Thung.) Hook & Arn.], sericea
 lespedeza [Lespedeza cuneata (Dum.) G. Don], and red clover (Trifolium pratense
 L.) did not survive the stressful conditions of the spoils. However, cowpea
 (Vigna unguiculata L.) followed by 'Bragg' soybean [Glycine max (L.) Merr.]
 generally produced the highest dry matter yield while accumulating the largest
 quantity of metals, except Al, from spoils. The extractability of most metals
 from the spoils was generally in the order of: 0.1 M HCl > Mehlich 1 > DTPA.
 Mehlich 1 did not extract Pb and 0.1 M HCl did not extract Ni, whereas DTPA
 extracted all the metals in a smiler amount relative to HCl and Mehlich 1. All
 the extractants were quite effective in removing plant-available Zn from the
 spoils. In general, the extractants' ability to predict plant-available metals
 depended on the crop species, spoil type, and extractant used.
 
 
 6                                                      NAL Call. No.: 23 AU783
 Acidification of soil associated with lupins grown in a crop rotation in
 north-eastern Victoria.
 Coventry, D.R.; Slattery, W.J.
 Melbourne : Commonwealth Scientific and Industrial Research Organization; 1991.
 Australian journal of agricultural research v. 42 (3): p. 391-397; 1991.
 Includes references.
 
 Language:  English
 
 Descriptors: Victoria; Lupinus; Rotations; Triticum; Acidification; Long term
 experiments; Leaching; Nitrates; Rain; Sandy loam soils; Soil acidity; Soil ph;
 Alkalinity; Crop yield; Continuous cropping
 
 
 7                                                      NAL Call. No.: 23 AU783
 Acidification of soil assoicated with lupins grown in a crop rotation in
 north-eastern Victoria.
 Coventry, D.R.; Slattery, W.J.
 Melbourne : Commonwealth Scientific and Industrial Research Organization; 1991.
 Australian journal of agricultural research v. 42 (3): p. 391-397; 1991.
 Includes references.
 
 Language:  English
 
 Descriptors: Victoria; Triticum; Lupinus; Soil acidity; Soil ph; Long term
 experiments; Rotations
 
 
 8                                                    NAL Call. No.: SB998.N4N4
 Additional studies on the use of bahiagrass for the management of root-knot and
 cyst nematodes in soybean.
 Rodriguez-Kabana, R.; Weaver, D.B.; Robertson, D.G.; Carden, E.L.; Pegues, M.L.
 Auburn, Ala. : Organization of Tropical American Nematologists; 1991 Dec.
 Nematropica v. 21 (2): p. 203-210; 1991 Dec.  Includes references.
 
 Language:  English
 
 Descriptors: Glycine max; Cultivars; Pest resistance; Heterodera glycines;
 Meloidogyne arenaria; Aldicarb; Chemical control; Cultural control;
 Monoculture; Nematode control; Paspalum notatum; Rotations
 
 
 9                                                    NAL Call. No.: S605.5.A43
 Agricultural use of organic amendments: a historical perspective.
 Parr, J.F.; Hornick, S.B.
 Greenbelt, Md. : Institute for Alternative Agriculture; 1992.
 American journal of alternative agriculture v. 7 (4): p. 181-189; 1992.
 Includes references.
 
 Language:  English
 
 Descriptors: Organic fertilizers; History; Erosion; Composting; Soil organic
 matter; Sewage sludge; Solid wastes; Soil fertility
 
 Abstract:  Agricultural research conducted in the United States since
 establishment of the U.S. Dept. of Agriculture and Land-Grant University
 System in 1862 has shown that regular and proper additions of organic
 materials are very important for maintaining the tilth, fertility, and
 productivity of agricultural soils, protecting them from wind and water
 erosion, and preventing nutrient losses by runoff and leaching. Several
 millennia earlier, Roman agriculturists were advocating crop rotations, green
 manuring, composts, legumes, farmyard manures, crop residues, wood ashes,
 seaweed, and sewage wastes for supplying humus and nutrients to restore or
 enhance soil productivity. Even earlier, Asian farmers also used these
 practices to maintain healthy and productive soils. Today the most serious
 problem in U.S. agriculture and agriculture worldwide is the widespread
 degradation of agricultural soils through erosion and the consequential
 decline in productivity. In view of how much information is available on the
 benefits of organic recycling on agricultural lands, one wonders why we aren't
 doing a better job of protecting and conserving our land resource base. We
 discuss strategies for using organic resources more effectively to achieve a
 more sustainable agriculture for the future.
 
 
 10                                                     NAL Call. No.: S601.A34
 Agroecosystem management effects on soil carbon and nitrogen.
 Wood, C.W.; Edwards, J.H.
 Amsterdam : Elsevier; 1992 Apr.
 Agriculture, ecosystems and environment v. 39 (3/4): p. 123-138; 1992 Apr.
 Includes references.
 
 Language:  English
 
 Descriptors: Alabama; Tillage; Conservation tillage; Continuous cropping;
 Rotations; Triticum aestivum; Zea mays; Glycine max; Soil fertility; Nitrogen;
 Carbon; Soil organic matter; Crop residues; Mineralization; Nutrient
 availability; Soil depth; Biological activity in soil; Subtropics
 
 
 11                                                    NAL Call. No.: 64.8 C883
 Allelopathy and autotoxicity in alfalfa: characterization and effects of
 preceding crops and residue incorporation.
 Hegde, R.S.; Miller, D.A.
 Madison, Wis. : Crop Science Society of America; 1990 Nov.
 Crop science v. 30 (6): p. 1255-1259; 1990 Nov.  Includes references.
 
 Language:  English
 
 Descriptors: Illinois; Medicago sativa; Sorghum bicolor; Rotations; Sequential
 cropping; Allelopathy; Allelopathins; Phytotoxicity; Crop residues; Roots;
 Shoots; Incorporation; Leachates; Bioassays; Seed germination; Growth rate
 
 Abstract:  Alfalfa (Medicago sativa L.) is known to be both autotoxic and
 allelopathic. Greenhouse and laboratory experiments were conducted to
 determine if 'WL-316' alfalfa exhibits short-term autotoxicity and long-term
 autotoxicity and allelopathy. Long-term autotoxicity and allelopathy of
 alfalfa were verified at Urbana, IL, by comparing the germination and growth of
 alfalfa and sorghum [Sorghum bicolor (L.) Moench] on Flanagan silt loam (fine,
 montmorillonitic, mesic Aquic Argiudoll) previously cropped to alfalfa
 (alfalfa-soil) and sorghum (sorghum-soil). Short-term autotoxicity of alfalfa
 was investigated by studying the effect of incorporating its roots only and
 both roots and shoots on the germination and growth of alfalfa in alfalfa-soil
 and sorghum-soil. The data were further supported by a laboratory bioassay of
 seedling exudate and shoot leachate of alfalfa and sorghum. Plant height and
 fresh weight per plant of alfalfa and fresh weight per plant of sorghum were
 lower on alfalfa-soil than on sorghum-soil. Germination percentages of both
 alfalfa and sorghum and plant height of sorghum were unaffected by the
 preceding crop. The two soils differed in nutrient content, but fertility was
 high and should not have been limiting to the growth of either crop. As a
 result, allelopathic/autotoxic compounds in alfalfa-soil were implicated in the
 growth inhibition of the two crops. Soil incorporation of fresh alfalfa roots
 only or both roots and shoots reduced alfalfa emergence, plant height, and dry
 weight per plant. Primary effects of water-soluble inhibitory
 compounds from alfalfa shoot appeared to be on germination and radicle
 elongation, the latter being apparently more sensitive than the former.
 Alfalfa allelopathy seems to be more severe than autotoxicity. A flow diagram
 describes different kinds of allelopathy and autotoxicity and various
 situations that verify the existence of a particular kind of allelopathy or
 autotoxicity.
 
 
 12                                                 NAL Call. No.: S494.5.S86S8
 Alternative soil and pest management practices for sustainable production of
 fresh-market cabbage.
 Roberts, B.W.; Cartwright, B.
 Binghamton, N.Y. : Food Products Press; 1991.
 Journal of sustainable agriculture v. 1 (3): p. 21-35; 1991.  Includes
 references.
 
 Language:  English
 
 Descriptors: Oklahoma; Brassica oleracea; Secale cereale; Vicia villosa; Cover
 crops; Soil; Sustainability; Soil management; Pest management
 
 
 13                                                   NAL Call. No.: SB998.N4N4
 American jointvetch and partridge pea for the management of Meloidogyne
 arenaria in peanut.
 Rodriguez-Kabana, R.; Robertson, D.G.; King, P.S.; Wells, L.
 Auburn, Ala. : Organization of Tropical American Nematologists; 1991 Jun.
 Nematropica v. 21 (1): p. 97-103; 1991 Jun.  Includes references.
 
 Language:  English
 
 Descriptors: Alabama; Arachis hypogaea; Crop yield; Meloidogyne arenaria;
 Nematode control; Aldicarb; Cultural control; Rotations; Antagonists;
 Aeschynomene Americana; Cassia
 
 
 14                                                   NAL Call. No.: 464.8 P692
 Analysis of disease-progress curves for take-all in consecutive crops of
 winter wheat.
 Werker, A.R.; Gilligan, C.A.; Hornby, D.
 Oxford : Blackwell Scientific Publications; 1991 Mar.
 Plant pathology v. 40 (1): p. 8-24; 1991 Mar.  Includes references.
 
 Language:  English
 
 Descriptors: Uk; Triticum aestivum; Phaseolus vulgaris; Gaeumannomyces
 graminis; Continuous cropping; Rotations; Infections; Disease models; Incidence
 
 Abstract:  Disease-progress curves of take-all, caused by Gaeumannomyces
 graminis var. tritici, were analysed for consecutive crops of winter wheat.
 Comparisons were made over 9 years amongst a sequence of consecutive wheats and
 first and second successive wheats grown after non-susceptible break crops
 (spring beans). The principal objectives were to identify differences in the
 shapes of the disease-progress curves that could be attributed to the
 rotational treatments. Shapes of disease-progress curves were summarized by
 average rate of disease increase and components for curvature together with the
 mean amount of disease. Analyses were done for curves based upon
 percentages of diseased plants and of diseased roots. Mean levels of disease in
 second and continuous wheats rose from the start of the experiment (1979) to
 reach a maximum in the middle years (1982-84) and thereafter declined. This
 pattern was absent in first wheats in which disease progress within years was
 rectilinear and comparatively slow. In second and continuous wheats, years of
 high disease were characterized by more marked curvature than years of low
 disease. For proportions of diseased plants, the rate of disease increase in
 second and continuous wheats slowed as the season progressed. Differences in
 shapes of disease-progress curves for second and continuous wheats were
 apparent when proportions of diseased roots rather than plants were
 considered. The average linear rate of increase in the proportion of diseased
 roots in continuous wheats was intermediate in magnitude between those of first
 and second wheats. Epidemics in second wheats were initially slow and
 accelerated as the season progressed, whilst in continuous wheats, an early
 faster rate of increase in disease subsequently slowed. Some epidemiological
 consequences of these effects are discussed in relation to the phenomenon of
 take-all decline, which is associated with the suppression of the disease in
 cereal monoculture. The effects of cropping
 
 
 15                                                   NAL Call. No.: 464.9 C16S
 Anthracnose and Ascochyta blight of lentil in central Saskatchewan in 1992.
 Morrall, R.A.A.; Beaule, R.; Ahmed, S.; Downing, J.L.; Pearse, P.G.
 Ottawa : Research Branch, Agriculture Canada; 1993.
 Canadian plant disease survey v. 73 (1): p. 91-92; 1993.  Includes references.
 
 Language:  English
 
 Descriptors: Saskatchewan; Lens culinaris; Ascochyta fabae; Blight;
 Colletotrichum truncatum; Fungal diseases; Rotations; Disease surveys
 
 
 16                                                     NAL Call. No.: 56.8 AU7
 Atrazine persistence and toxicity in two irrigated soils of Australia.
 Bowmer, K.H.
 East Melbourne : Commonwealth Scientific and Industrial Research Organization;
 1991.
 Australian journal of soil research v. 29 (2): p. 339-350; 1991.  Includes
 references.
 
 Language:  English
 
 Descriptors: New South Wales; Zea mays; Atrazine; Herbicide residues;
 Persistence; Irrigated soils; Clay soils; Soil temperature; Phytotoxicity;
 Bioassays; Glycine max; Avena sativa; Brassica campestris var. rapa; Rotations
 
 
 17                                                  NAL Call. No.: S592.7.A1S6
 Availability of N from 15N-labeled alfalfa residues to three succeeding barley
 crops under field conditions.
 Ta, T.C.; Faris, M.A.
 Exeter : Pergamon Press; 1990.
 Soil biology and biochemistry v. 22 (6): p. 835-838; 1990.  Includes
 references.
 
 Language:  English
 
 Descriptors: Nitrogen; Availability; Labeling; Medicago sativa; Crop residues;
 Hordeum vulgare; Field crops; Rotations; Dry matter; Cropping systems; Nitrogen
 fixation
 
 
 18                                                     NAL Call. No.: 100 AL1H
 Bahiagrass in rotations shows promise for boosting peanut yields.
 Jacobi, J.C.; Backman, P.A.; Rodriguez-Kabana, R.; Robertson, D.G.
 Auburn University, Ala. : The Station; 1991.
 Highlights of agricultural research - Alabama Agricultural Experiment Station
 v. 38 (2): p. 7; 1991.
 
 Language:  English
 
 Descriptors: Alabama; Arachis hypogaea; Crop yield; Fungal diseases; Disease
 control; Paspalum notatum; Rotations
 
 
 19                                                    NAL Call. No.: 64.8 C883
 Barley semidwarf and standard isotype yield and malting quality response to
 nitrogen.
 Nedel, J.L.; Ullrich, S.E.; Clancy, J.A.; Pan, W.L.
 Madison, Wis. : Crop Science Society of America, 1961-; 1993 Mar.
 Crop science v. 33 (2): p. 258-263; 1993 Mar.  Includes references.
 
 Language:  English
 
 Descriptors: Washington; Cabt; Hordeum vulgare; Mutants; Dwarf cultivars;
 Isotypes; Application rates; Nitrogen fertilizers; Correlated responses; Crop
 yield; Crop quality; Malting quality; Grain; Yield components; Malting barley;
 Rotations
 
 Abstract:  Introduction of certain semidwarf genes into wheat (Triticum spp.)
 has improved N-use efficiency, particularly at high N supply. This study was
 conducted to determine whether yield and grain quality differ between standard
 height (STD) and mutant semidwarf (SD) malting barley (Hordeum vulgare L.)
 isotypes with varying levels of N supply. Isotype pairs ('Morex', 'Hazen',
 'Norbert', and 'Andre') and check cultivars (Steptoe, Klages) were grown with
 30, 60, 90, and 120 kg N ha-1 in 1987 and 1989. Yield, grain characteristics,
 and malting quality parameters were evaluated. The STD isotypes had higher
 yield (6781 vs. 5642 and 5202 vs. 4504 kg ha-1 in 1987 and 1989, respectively)
 and generally higher values for yield components and harvest index, as well as
 better grain quality than their respective SD isotypes; however, two-row SD
 isotypes had better malting quality than their STD isotypes. The generally
 superior performance of STD isotypes in part may be due to the SD isotypes
 being raw induced mutants that had not been improved by crossing. Malting
 quality parameters, such as total malt protein and malt extract, were affected
 negatively by N >60 kg ha-1, when the preceding crop was pea (Pisum sativum L.;
 high N); however, for yield and some malt quality parameters such as
 diastatic power, all genotypes responded significantly and positively to N
 fertilization when the preceding crop was barley (low N). In general, the
 response to N was similar for both barley types. As SD malting barley
 cultivars are developed to control lodging, they may not utilize more N or
 yield more than STD types.
 
 
 20                                                 NAL Call. No.: S544.3.M9M65
 Berseem clover: a potential hay and green manure crop for Montana.
 Baldridge, D.; Dunn, R.; Ditterline, R.; Sims, J.; Welty, L.; Wichman, D.;
 Westcott, M.; Stalknecht, G.
 Bozeman, Mont. : The Service; 1992 Jan.
 Montguide MT : Agriculture - Montana State University, Cooperative Extension
 Service (9201): 3 p.; 1992 Jan.  Includes references.
 
 Language:  English
 
 Descriptors: Montana; Trifolium alexandrinum; Bloat; Hay; Crop yield; Field
 tests; Nutrient content; Green manures
 
 
 21                                                   NAL Call. No.: S540.A2F62
 Best lupine or vetch and N fertilizer management practice for optimizing corn
 ear leaf area, dry weight and N concentration.
 Hagendorf, B.A.; Gallaher, B.N.
 Gainesville, Fla. : The Stations; 1992.
 Agronomy research report AY - Agricultural Experiment Stations, University of
 Florida (92-04): 17 p.; 1992.  Includes references.
 
 Language:  English
 
 Descriptors: Zea mays; Vicia villosa; Lupinus angustifolius; Leaf area;
 Nitrogen fertilizers; Cover crops; Tillage; Soil management; Nitrogen content;
 Dry matter
 
 
 22                                                    NAL Call. No.: S596.7.D4
 Biological N2 fixation in wetland rice fields: estimation and contribution to
 nitrogen balance.
 Rogers, P.A.; Ladha, J.K.
 Dordrecht : Kluwer Academic Publishers; 1992.
 Developments in plant and soil sciences v. 49: p. 41-55; 1992.  In the series
 analytic: Biological nitrogen fixation for sustainable agriculture / edited by
 J.K. Ladha, T. George, and B.B. Bohlool. Extended versions of papers presented
 in the symposium "Role of biological nitrogen fixation in sustainable
 agriculture", 1990, Kyoto, Japan.  Includes references.
 
 Language:  English
 
 Descriptors: Oryza sativa; Nitrogen fixation; Estimation; Analytical methods;
 Saturated conditions; Reviews
 
 Abstract:  This paper 1) reviews improvements and new approaches in
 methodologies for estimating biological N2 fixation (BNF) in wetland soils, 2)
 summarizes earlier quantitative estimates and recent data, and 3) discusses the
 contribution of BNF to N balance in wetland-rice culture. Measuring
 acetylene reducing activity (ARA) is still the most popular method for
 assessing BNF in rice fields. Recent studies confirm that ARA measurements
 present a number of problems that may render quantitative extrapolations
 questionable. On the other hand, few comparative measures show I ARA's
 potential as a quantitative estimate. Methods for measuring photodependent and
 associative ARA in field studies have been standardized, and major progress has
 been made in sampling procedures. Standardized ARA measurements have shown
 significant differences in associative N2 fixation among rice varieties. The
 15N dilution method is suitable for measuring the percentage of N derived from
 the atmosphere (% Ndfa) in legumes and rice. In particular, the N dilution
 technique, using available soil N as control, appears to be a promising method
 for screening rice varieties for ability to utilize biologically fixed N.
 Attempts to adapt the 15N dilution method to aquatic N2 fixers Azolla and blue-
 green algae [BGA]) encountered difficulties due to the rapid change in N
 enrichment of the water. Differences in natural 15N abundance have been used to
 show differences among plant organs and species or varieties in rice and
 Azolla, and to estimate Ndfa by Azolla, but the method appears to be
 semi-quantitative. Recent pot experiments using stabilized 15N-labelled soil or
 balances in pots covered with black cloth indicate a contribution of 10-30 kg N
 ha-1 crop-1 by heterotrophic BNF in flooded planted soil with no or
 little N fertilizer used. Associative BNF extrapolated from ARA and 15N
 incorporation range from 1 to 7 kg N ha-1 crop-1 Straw application increases
 heterotrophic and photodependent BNF. Pot experiments show N gains of 2-4 mg N
 g-1 straw added at 10 tons ha-1. N2 fixation by BGA has been almost
 exclusively estimated by ARA and biomass measurements. Estimates by ARA range
 from a few to 80 kg N ha-1 crop (average 27 kg). Recent extensive measurements
 show extrapolated values of about 20 kg N ha-1 crop-1 in no-N plots, 8 kg in
 plots with broadcast urea, and 12 kg in plots with deep-placed urea. Most
 information on N2 fixed by Azolla and legume green manure comes from N
 accumulation measurements and determination of % Ndfa. Recent trials in an
 international network show standing crops of Azolla averaging 30-40 kg N ha-1
 and the accumulation of 50-90 kg N ha-1 for two crops of Azolla grown before
 and after transplanting rice. Estimates of % Ndfa in Azolla by 15N dilution and
 delta 15N methods range from 51 to 99%. Assuming 50-80% Ndfa in legume green
 manures, one crop can provide 50-100 kg N ha-1 in 50 days. Few balance studies
 in microplots or pots report extrapolated N gains of 150
 
 
 23                                                    NAL Call. No.: TD930.A32
 Bioresource potential of Sesbania bispinosa (Jacq.) W. F. Wight.
 Prasad, M.N.V.
 Essex : Elsevier Science Publishers; 1993.
 Bioresource technology v. 44 (3): p. 251-254; 1993.  Includes references.
 
 Language:  English
 
 Descriptors: Sesbania bispinosa; Green manures; Salt tolerance
 
 
 24                                                       NAL Call. No.: HD1.A3
 Calibration and validation EPIC for crop rotations in southern France.
 Cabelguenne, M.; Jones, C.A.; Marty, J.R.; Dyke, P.T.; Williams, J.R.
 Essex : Elsevier Applied Science Publishers; 1990.
 Agricultural systems v. 33 (2): p. 153-171; 1990.  Includes references.
 
 Language:  English
 
 Descriptors: France; Zea mays; Sorghum bicolor; Helianthus annuus; Glycine max;
 Triticum aestivum; Rotations; Simulation models; Computer software;
 Calibration; Growth; Crop yield; Biomass; Crop management; Estimation;
 Statistical analysis
 
 
 25                                                      NAL Call. No.: 4 AM34P
 Carbon and phosphorus losses from decomposing crop residues in no-till
 conventional till agroecosystems.
 Buchanan, M.; King, L.D.
 Madison, Wis. : American Society of Agronomy, [1949-; 1993 May.
 Agronomy journal v. 85 (3): p. 631-638; 1993 May.  Includes references.
 
 Language:  English
 
 Descriptors: North Carolina; Cabt; Triticum aestivum; Glycine max; Trifolium
 incarnatum; Zea mays; No-tillage; Tillage; Crop residues; Decomposition;
 Cycling; Carbon; Phosphorus; Shoots; Roots; Grain; Leaves; Mineralization;
 Losses from soil; Winter; Cover crops; Lignin; Nitrogen; Plant composition
 
 Abstract:  An increased knowledge of crop residue decomposition
 characteristics is a critical component for nutrient cycling studies in
 agroecosystems. Carbon and P losses from shoot residues of maize (Zea mays L.),
 wheat [Triticum aestivum (L.), emend. Thell], soybean [Glycine mar L.) Merr.],
 and shoot and root residues of crimson clover (Trifolium incarnatum L.) were
 compared in no-till and conventional till systems. Grain crop
 residues were generally collected from senescent plants following harvest and
 placed in fiberglass mesh litter bags. Soybean leaf residues, however, were
 sampled following preharvest abscission, while crimson clover residues were
 collected at spring anthesis and buried only in a conventional till system.
 Generally, the changes in C and P content of residues were best described by
 exponential and/or logarithmic functions. Losses of C and P from crop residues
 were consistently greater, and more rapid when residues were buried vs. left on
 the soil surface. Crimson clover shoots lost C and P more rapidly than root
 residues. Generally, greater initial losses of P than of C occurred in most
 residues. The lack of correlation between C and P losses is believed to be due
 to an initial and probably variable inorganic P content that is readily
 leached prior to the decomposition and mineralization losses of C. Differences
 in the rate and magnitude of C losses were related to seasonal effects, the
 initial N and P content, and/or the proportional amount of lignin in the plant
 residues. Tillage is clearly an important regulator or driving variable for
 element cycling in agroecosystems.
 
 
 26                                                    NAL Call. No.: SB610.W39
 Carryover of DPX-PE350 to grain sorghum (Sorghum bicolor) and soybean (Glycine
 max) on two Arkansas soils.
 Jordan, D.L.; Johnson, D.H.; Johnson, W.G.; Kendig, J.A.; Frans, R.E.; Talbert,
 R.E.
 Champaign, Ill. : The Weed Science Society of America; 1993 Jul.
 Weed technology : a journal of the Weed Science Society of America v. 7 (3): p.
 645-649; 1993 Jul.  Includes references.
 
 Language:  English
 
 Descriptors: Arkansas; Cabt; Gossypium hirsutum; Rotations; Glycine max;
 Sorghum bicolor; Sequential cropping; Herbicides; Residual effects;
 Persistence; Application rates; Abiotic injuries; Crop damage; Phytotoxicity;
 Crop yield; Degradation; Edaphic factors; Silt loam soils; Clay soils; Weed
 control; Chemical control
 
 
 27                                                      NAL Call. No.: 4 AM34P
 Cation and nitrate leaching in an oxisol of the Brazilian Amazon.
 Cahn, M.D.; Bouldin, D.R.; Cravo, M.S.; Bowen, W.T.
 Madison, Wis. : American Society of Agronomy, [1949-; 1993 Mar.
 Agronomy journal v. 85 (2): p. 334-340; 1993 Mar.  Includes references.
 
 Language:  English
 
 Descriptors: Brazil; Cabt; Oxisols; Nitrate nitrogen; Leaching; Zea mays; Crop
 yield; Canavalia ensiformis; Mucuna aterrima; Urea; Lime; Soil fertility;
 Topsoil; Acidification; Cations; Calcium; Magnesium; Potassium; Losses from
 soil; Humid tropics
 
 Abstract:  High rates of N fertilizers are often necessary to achieve yield
 goals in the humid tropics, where subsoil acidity prevents deep crop rooting.
 However, leaching of fertilizer nitrate may accelerate the leaching of bases
 from the crop rooting zone, leading to an acidification of the topsoil and a
 reduction in crop yields. Our ojective was to investigate the influence of urea
 and legume green manure sources of N on crop yields, leaching of cations, and
 the fertility of the plow layer of a clayey Oxisol (Typic Acrudox) of the
 central Amazon basin. We established a split-plot field experiment near
 Manaus, Brazil where main plots received 2 levels of lime (O and 4 Mt/ha
 CaCO3) and sub-plots were cropped with (i) a legume green manure (Canavalia
 ensiformes L. or Mucuna aterrima L.) followed by maize (Zea mays L.); (ii)
 maize receiving 300 kg ha-(1) of urea-N, or (iii) left bare-fallow with an
 application f 300 kg ha(-1) of urea-N. Plots were periodically sampled to 1.2 m
 during three cropping seasons. The field site received 4265 mm of rain
 during the experiment (16 mo). Legume crops accumulated between 142 and 280 kg
 ha(-1) of N. The distribution of NO3 in the soil profile changed in a pattern
 consistent with leaching. All treatments lost Ca and Mg from the plow layer
 during the experimental period. Losses were greatest (500-1000 kg ha(-1) for Ca
 and 50 kg ha(-1) for Mg) in plots treated with urea and lime. Leaching of bases
 and the generation of acidity decreased base saturation in the plow layer of
 all treatments, but was minimized in plots receiving legume green manure N,
 perhaps because less inorganic N was applied and/or the legume crops recycled
 leached bases. Unlimed plots receiving urea, bad the highest increase in
 acidity in the 0 to 30-cm layer and a corresponding 44% reduction in grain
 yield between the first and third maize crops.
 
 
 28                                                  NAL Call. No.: SB610.2.B74
 Changes in weed populations and seed bank through two cycles of a
 maize-soyabean rotation in Ontario, Canada.
 Benoit, D.L.; Swanton, C.J.; Chandler, K.; Derksen, D.A.
 Surrey : BCPC Registered Office; 1991.
 Brighton Crop Protection Conference-Weeds v. 1: p. 403-410; 1991.  Includes
 references.
 
 Language:  English
 
 Descriptors: Ontario; Zea mays; Glycine max; Rotation; Weed control;
 Herbicides; Minimum tillage; Seed banks
 
 
 29                                                      NAL Call. No.: 10 J822
 Changes induced by cowpea green manure and farmyard manure in the timing of
 phenological events in maize (Zea mays).
 Aggarwal, G.C.; Sekhon, N.K.
 Cambridge : Cambridge University Press; 1991 Oct.
 The Journal of agricultural science v. 117 (pt.2): p. 157-163; 1991 Oct.
 Includes references.
 
 Language:  English
 
 Descriptors: India; Zea mays; Farmyard manure; Green manures; Phenology;
 Timing; Vigna unguiculata; Application rates; Crop yield
 
 
 30                                                   NAL Call. No.: QH84.8.B46
 Characterization of the N benefit of a grain legume (Lupinus angustifolius L.)
 to a cereal (Hordeum vulgare L.) by an in situ 15N isotope dilution technique.
 Chalk, P.M.; Smith, C.J.; Hamilton, S.D.; Hopmans, P.
 Berlin : Springer International; 1993.
 Biology and fertility of soils v. 15 (1): p. 39-44; 1993.  Includes
 references.
 
 Language:  English
 
 Descriptors: Victoria; Hordeum vulgare; Lupinus angustifolius; Isotope
 labeling; Nitrogen fertilizers; Nitrogen fixation; Nutrient availability;
 Rotations; Soil fertility
 
 
 31                                                     NAL Call. No.: 56.9 SO3
 Chemical attributes of soils subjected to no-till cropping with rye cover
 crops.
 Eckert, D.J.
 Madison, Wis. : The Society; 1991 Mar.
 Soil Science Society of America journal v. 55 (2): p. 405-409; 1991 Mar.
 Includes references.
 
 Language:  English
 
 Descriptors: Ohio; Secale cereale; Zea mays; Glycine max; Soil chemistry;
 Calcium; Carbon; Magnesium; Nitrogen fertilizers; Phosphorus; Potassium; No-
 tillage; Rotations; Soil fertility; Soil physical properties
 
 Abstract:  Rye (Secale cereale L.) cover crops are often promoted to supply
 additional residue in no-till production situations; however, the effect of
 inclusion of rye on soil chemical properties is largely unknown. Soils were
 sampled, 20 cm deep, from four 4-yr studies in which no-till corn (Zea mays L.)
 and soybean (Glycine max L. Merr.) were grown continuously or in rotation on a
 Canfield silt loam (fine-loamy, mixed, mesic Aquic Fragiudalf) or in rotation
 only on a Hoytville silty clay (fine, illitic, mesic Mollic
 Ochraqualf), with and without a winter rye cover crop. Corn had been
 fertilized each spring with 224 kg N ha(-1) as either injected anhydrous
 ammonia or surface-broadcast urea-ammonium nitrate (UAN) solution. All plots
 sampled showed greater concentrations of organic C, exchangeable K, and Bray-1
 extractable P in the surface 5-cm increment of soil than deeper in the sampled
 profile. Exchangeable Ca and Mg concentrations were often less at this depth
 than deeper in the profile, particularly when N was applied as
 surface-broadcast UAN solution. Soil pH was generally lowest in the zone of N
 application. Addition of the rye cover crop had little effect on the
 distribution of chemical attributes, other than increasing concentrations of
 exchangeable K near the soil surface in several comparisons.
 
 
 32                                                    NAL Call. No.: SB610.W39
 Chlorsulfuron persistence and response of nine rotational crops in alkaline
 soils of southern Alberta.
 Moyer, J.R.; Esau, R.; Kozub, G.C.
 Champaign, Ill. : The Society; 1990 Jul.
 Weed technology : a journal of the Weed Science Society of America v. 4 (3): p.
 543-548; 1990 Jul.  Includes references.
 
 Language:  English
 
 Descriptors: Alberta; Medicago sativa; Hordeum vulgare; Phaseolus vulgaris;
 Brassica napus; Linum usitatissimum; Lens culinaris; Pisum sativum; Beta
 vulgaris; Solanum tuberosum; Triticum aestivum; Rotations; Weed control;
 Chemical control; Chlorsulfuron; Persistence; Application rates; Herbicide
 residues; Alkaline soils; Soil ph
 
 
 33                                                     NAL Call. No.: 80 AM371
 A clean choice.
 Bremer, A.H.
 Chicago, Ill. : American Nurseryman Publishing Company; 1993 Jun01.
 American nurseryman v. 177 (11): p. 38-41; 1993 Jun01.
 
 Language:  English
 
 Descriptors: Ornamental woody plants; Plantations; Cover crops; Trifolium
 pratense; Grasses; Crop mixtures
 
 
 34                                                    NAL Call. No.: SB610.W39
 Clopyralid influences rotational crops.
 Thorsness, K.B.; Messersmith, C.G.
 Champaign, Ill. : The Society; 1991 Jan.
 Weed technology : a journal of the Weed Science Society of America v. 5 (1): p.
 159-164; 1991 Jan.  Includes references.
 
 Language:  English
 
 Descriptors: North Dakota; Linum usitatissimum; Lens culinaris; Solanum
 tuberosum; Carthamus tinctorius; Glycine max; Helianthus annuus; Rotations;
 Clopyralid; Herbicide residues; Persistence; Dicamba; Crop yield; Yield losses;
 Phytotoxicity
 
 
 35                                                    NAL Call. No.: SB610.W39
 Combining cultural practices and herbicides to control wild-proso millet
 (Panicum miliaceum).
 Harvey, R.G.; McNevin, G.R.
 Champaign, Ill. : The Society; 1990 Apr.
 Weed technology : a journal of the Weed Science Society of America v. 4 (2): p.
 433-439; 1990 Apr.  Paper presented at the "Symposium on Wild-Proso
 Millet," February 9, 1989, Dallas, Texas.  Includes references.
 
 Language:  English
 
 Descriptors: Zea mays; Medicago sativa; Panicum miliaceum; Chemical vs.
 cultural weed control; Cultural weed control; Rotations; Direct sowing;
 Planting date; No-tillage; Row spacing; Chemical control; Alachlor; Atrazine;
 Cyanazine; Dichlormid; Eptc; Pendimethalin; Simazine; Crop yield; Integrated
 control
 
 
 36                                                  NAL Call. No.: HD1773.A3N6
 Commodity programs and the internalization of erosion costs: Do they affect
 crop rotation decisions?.
 Poe, G.L.; Klemme, R.M.; McComb, S.J.; Ambrosious, J.E.
 East Lansing, Mich. : Michigan State University; 1991 Jul.
 Review of agricultural economics v. 13 (2): p. 223-235; 1991 Jul.  Includes
 references.
 
 Language:  English
 
 Descriptors: Wisconsin; Maize; Soybeans; Oats; Alfalfa; Rotations; Commodities;
 Erosion; Production costs; Risk; Returns; Decision making; Federal programs;
 Program participants; Stochastic processes; History; Market prices
 
 Abstract:  This paper investigates the impact of commodity programs and the
 internalization of erosion costs on crop rotation decisions. Not surprisingly,
 commodity programs are found to shift decisions toward more erosive rotations.
 Internalization of on-site and off-site erosion costs calculated under real
 interest rates of 2 and 4 percent and planning horizons of 20 and 40 years
 affect rotation decisions under historical market conditions. Under conditions
 of commodity program participation, internalization of erosion costs affect
 rotation decisions only when lengthy time horizons (40 years) are considered.
 The impact of cross-compliance restrictions on rotation decisions is also
 examined.
 
 
 37                                                    NAL Call. No.: SB610.W39
 Common lambsquarters (Chenopodium album) and rotational crop response to
 imazethapyr in pea (Pisum sativum) and snap bean (Phaseolus vulgaris).
 Vencill, W.K.; Wilson, H.P.; Hines, T.E.; Hatzios, K.K.
 Champaign, Ill. : The Society; 1990 Jan.
 Weed technology : a journal of the Weed Science Society of America v. 4 (1): p.
 39-43; 1990 Jan.  Includes references.
 
 Language:  English
 
 Descriptors: Pisum sativum; Phaseolus vulgaris; Rotations; Sorghum bicolor;
 Cucumis sativus; Zea mays; Herbicide residues; Residual effects; Chenopodium
 album; Crop yield; Herbicide application
 
 
 38                                                      NAL Call. No.: 450 C16
 Comparative effects of grain lentil-wheat and monoculture wheat on crop
 production, N economy and N fertility in a Brown Chernozem.
 Campbell, C.A.; Zentner, R.P.; Selles, F.; Biederbeck, V.O.; Leyshon, A.J.
 Ottawa : Agricultural Institute of Canada; 1992 Oct.
 Canadian journal of plant science; Revue canadienne de phytotechnie v. 72 (4):
 p. 1091-1107; 1992 Oct.  Includes references.
 
 Language:  English
 
 Descriptors: Saskatchewan; Lens culinaris; Triticum aestivum; Rotations;
 Ammonium nitrate; Leaching; Mineralization; Nitrogen fixation; Soil fertility;
 Soil water
 
 
 39                                                      NAL Call. No.: 450 C16
 Comparative plowdown value of red clover strains.
 Christie, B.R.; Clark, E.A.; Fulkerson, R.S.
 Ottawa : Agricultural Institute of Canada; 1992 Oct.
 Canadian journal of plant science; Revue canadienne de phytotechnie v. 72 (4):
 p. 1207-1213; 1992 Oct.  Includes references.
 
 Language:  English
 
 Descriptors: Ontario; Trifolium pratense; Cultivars; Green manures; Zea mays;
 Crop production; Crop yield
 
 
 40                                                  NAL Call. No.: HD1773.A3N6
 A comparison of farmers' compliance costs to reduce excess nitrogen fertilizer
 use under alternative policy options.
 Huang, W.; Lantin, R.M.
 East Lansing, MI : Dept. of Agricultural Economics, Michigan State University,
 1991-; 1993 Jan.
 Review of agricultural economics v. 15 (1): p. 51-62; 1993 Jan.  Includes
 references.
 
 Language:  English
 
 Descriptors: Iowa; Cabt; Nitrogen fertilizers; Program participants; Rotations;
 Farm comparisons; Production costs; Zea mays; Crop yield; Glycine max;
 Leaching; Case studies
 
 Abstract:  Farmers' compliance associated with using different crop rotation
 patterns under alternative farm policy options are estimated. The policy
 options considered include the Current Farm Program, a No Farm Program Option,
 a Nitrogen Fertilizer Tax Option, a Corn Sales Tax Option, and a Limiting
 Nitrogen Fertilizer Use Option. To achieve an objective of zero excess
 nitrogen fertilizer available for potential leaching into groundwater, crop
 rotation patterns associated with the Limiting Nitrogen Fertilizer Use Option
 have the lowest cost to the farmer. If some excess nitrogen is allowed, crop
 rotation compliance under the Farm Program has the lowest cost.
 
 
 41                                                     NAL Call. No.: 23 Au792
 A comparison of the persistence of Medicago truncatula cv. Paraggio with other
 annual medics in the Victorian Mallee.
 Latta, R.A.; Quigley, P.E.
 East Melbourne, Vic. Australia : Commonwealth Scientific and Industrial
 Research Organization, c1985-; 1993.
 Australian journal of experimental agriculture v. 33 (4): p. 443-449; 1993.
 Includes references.
 
 Language:  English
 
 Descriptors: Victoria; Cabt; Medicago truncatula; Cultivars; Crop production;
 Persistence; Plant density; Rotations; Seeds
 
 
 42                                                    NAL Call. No.: S605.5.B5
 Comparison of weed biomass and flora in four cover crops and a subsequent
 lettuce crop on three New England organic farms.
 Schonbeck, M.; Browne, J.; Deziel, G.; DeGregorio, R.
 Oxon : A B Academic Publishers; 1991.
 Biological agriculture and horticulture : an international journal v. 8 (2): p.
 123-143; 1991.  Includes references.
 
 Language:  English
 
 Descriptors: Fagopyrum esculentum; Fagopyrum tataricum; Secale cereale; Avena
 sativa; Sorghum bicolor; Trifolium pratense; Lolium multiflorum; Echinochloa
 crus-galli; Cover crops; Lactuca sativa; Cultural weed control; Weeds; Biomass;
 Botanical composition; Dry matter accumulation; Coverage; Crop residues; Crop
 weed competition; Environmental factors; Climatic factors; Soil fertility; Crop
 yield; Establishment; Regrowth; Suppression; Tillage
 
 
 43                                                      NAL Call. No.: 4 AM34P
 Conserving residual corn fertilizer nitrogen with winter cover crops.
 Shipley, P.R.; Meisinger, J.J.; Decker, A.M.
 Madison, Wis. : American Society of Agronomy; 1992 Sep.
 Journal of the American Society of Agronomy v. 84 (5): p. 869-876; 1992 Sep.
 Includes references.
 
 Language:  English
 
 Descriptors: Maryland; Zea mays; Nitrogen fertilizers; Nitrogen; Uptake;
 Winter; Cover crops; Vicia villosa; Trifolium incarnatum; Secale cereale;
 Lolium multiflorum; Fallow; Weed control; Stellaria media; Nutrients;
 Conservation; Recovery; Dry matter accumulation; Silt loam soils
 
 Abstract:  Autumn residual fertilizer nitrogen (FN) can be easily leached into
 groundwater in humid climates. Winter cover crops were evaluated for their
 ability to assimilate residual corn FN and thereby reduce N losses. Labelled FN
 (15N depleted) was applied to corn in Maryland in 1986 and 1987 at rates of 0,
 168, and 336 kg FN ha-1 on a Mattapex silt loam (fine-loamy, mixed, typic
 Hapludult). Cover crop treatments following corn harvest were hairy vetch
 (Vicia villosa Roth), crimson clover (Trifolium incarnatum L.), cereal rye
 (Secale cereale L.), or annual ryegrass (Lolium multiflorum Lam.), and a
 weed/fallow control of chickweed (Stellaria media L.). The covers were
 harvested three times the following spring and dry matter yields (DM), %N, and
 atom % 15N were determined to assess FN uptake. Fall labelled N in the soil (to
 80 cm) averaged 17 and 114 kg FN ha-1 over both years for the 168 and 336 kg FN
 ha-1 rates, respectively. However, the quantity of total residual
 mineral N (soil N plus FN) after the 168 kg ha-1 rate was 87 kg N ha-1, which
 was comparable to the quantity of labelled N at the high fertilizer rate. The
 average cover crop FN uptake (kg FN ha-1) in mid-April after the 336 kg N ha-1
 treatment was 48 for cereal rye, 29 for annual ryegrass, 9 for hairy vetch, 8
 for crimson clover, and 6 kg FN ha-1 for the native weed cover (LSD P = 0.05 of
 7 kg FN ha-1). Corresponding percent recoveries of the fall N in the
 aboveground DM were 45% for cereal rye, 27% for annual ryegrass, 10% for hairy
 vetch, 8% for crimson clover, and 8% for native weed cover. These results show
 that grass cover crops conserved the most FN. Cereal rye recovered wore FN
 through mid-April because of its growth in cool weather, although annual
 ryegrass was equally effective if grown to mid-May. Renewed efforts should be
 made to utilize grass cover crops to conserve N in humid climates.
 
 
 44                                                      NAL Call. No.: 4 AM34P
 Continous application of no-tillage to Ohio soils.
 Dick, W.A.; McCoy, E.L.; Edwards, W.M.; Lal, R.
 Madison, Wis. : American Society of Agronomy; 1991 Jan.
 Agronomy journal v. 83 (1): p. 65-73. ill., maps; 1991 Jan.  Paper presented at
 the Symposium on Long-Term Field Research, October 17-18, 1989.  Includes
 references.
 
 Language:  English
 
 Descriptors: Ohio; Zea mays; Glycine max; No-tillage; Plowing; Monoculture;
 Rotations; Long term experiments; Crop yield; Grain; Sustainability; Soil
 properties; Erosion; Runoff
 
 Abstract:  No-tillage (NT) crop production practices have been continuously
 maintained at four sites in Ohio for more than 25 yr. The original experiments
 involving NT were designed to determine how much tillage was required to
 produce crops with satisfactory yields and how tillage and rotation interact to
 effect crop yields, especially corn (Zea mays L.). Long-term effects of NT on
 crop yields and soil properties are generally not known because few sites exist
 with histories of greater than or equal to 20 yr of NT. This paper
 reports yield trends of corn and soybean [Glycine max (L.) Merr.] and changes
 in soil properties that occurred when NT was continuously practiced on soils in
 Ohio. Significantly lower yields for NT, as compared to conventional
 tillage (CT), were observed for monoculture corn and for soybean in rotation
 during the first 18 yr on a very poorly drained Mollic Ochraqualf soil. The
 yield differences observed for corn could be largely eliminated by crop
 rotation and for soybean by the use of phytophthera resistant/tolerant soybean
 cultivars. On a well-drained Typic Fragiudalf soil, crop yields were always
 higher with NT than with CT. After 18 yr, yield trends indicated the negative
 impact of NT on the very poorly drained soil was greatly decreased and the
 yield advantages associated with NT on the well-drained soil became even more
 pronounced. The change in yield treads did not appear to be associated with
 change in weather patterns. The long-term NT sites also revealed organic
 matter, nutrients, and soil enzymes accumulated at the soil surface but
 decreased deeper (>20 cm) in the soil profile. Surface water runoff was found
 to be greatly decreased from the long-term NT watershed site (approximately 9%
 slope) with only 12 mm of runoff measured between 1979 and 1985.
 
 
 45                                                    NAL Call. No.: SB610.W39
 Control of legume cover crops in no-till corn (Zea mays) and cotton (Gossypium
 hirsutum).
 White, R.H.; Worsham, A.D.
 Champaign, Ill. : The Society; 1990 Jan.
 Weed technology : a journal of the Weed Science Society of America v. 4 (1): p.
 57-62; 1990 Jan.  Includes references.
 
 Language:  English
 
 Descriptors: North Carolina; Zea mays; Gossypium hirsutum; No-tillage;
 Trifolium incarnatum; Vicia villosa; Vegetation management; Herbicide
 application; Paraquat; Dicamba; 2,4-d; Cyanazine; Glyphosate; Crop
 establishment; Crop yield
 
 
 46                                                   NAL Call. No.: S542.A8A34
 Control of peanut bacterial wilt through crop rotation.
 Machmud, M.
 Canberra, A.C.T. : Australian Centre for International Agricultural Research,
 1985-; 1993.
 ACIAR proceedings (45): p. 221-224; 1993.  In the series analytic: Bacterial
 wilt / edited by G.L. Hartman and A.C. Hayward.  Meeting held on October
 28-31, 1992, Kaohsiung, Taiwan.  Includes references.
 
 Language:  English
 
 Descriptors: Arachis hypogaea; Pseudomonas solanacearum; Wilts; Plant disease
 control; Rotations
 
 
 47                                                  NAL Call. No.: QL391.N4J62
 Control of the soybean cyst nematode by crop rotation in combination with a
 nematicide.
 Sasser, J.N.; Uzzell, G. Jr
 Lake Alfred, Fla. : Society of Nematologists; 1991 Jul.
 Journal of nematology v. 23 (3): p. 344-347; 1991 Jul.  Includes references.
 
 Language:  English
 
 Descriptors: North Carolina; Glycine max; Zea mays; Heterodera glycines;
 Nematode control; Rotation; 1,3-dichloropropene
 
 Abstract:  An experiment to evaluate the control of soybean cyst nematodes
 compared 1 year, 2-year, and 3-year nonhost rotations with continuous soybeans
 (Glycine max) in 0.2-ha plots. In a second 1-year rotation, the plots were
 planted to soybean or corn (Zea mays) after fumigation in the spring with a
 split application of 1,3-dichloropropene (748.2 liters/ha). The effects of the
 nematicide were apparent the first year. Soybean yield was 1,482 kg/ha
 compared to 233 kg/ha in the untreated plots. In the second year, the highest
 yielding plants (2,035 kg/ha) were those following 1 year of corn that had been
 treated the previous year: plants in untreated plots yielded 288 kg/ha. Average
 yield of soybean following 1 year of corn was 957 kg/ha compared to 288 kg/ha
 for continuous soybean. In the third year, the effects of the
 nematicide were still evident. Soybean plants in plots treated the first year
 followed by corn, then soybean, yielded 1,044 kg/ha compared to 761 kg/ha for
 soybean following 1 year of corn and 991 kg/ha for soybean following 2 years of
 corn. Plots planted to soybean for 3 consecutive years yielded 337 kg/ha.
 Nematicidal effects were no longer evident during the fourth year. Yields were
 most improved by the greatest number of years in the nonhost crop: highest
 yields in descending order were from plants following 3 years of-corn, 2 years
 of corn, and 1 year of corn. Plots planted to soybean for 4 consecutive years
 yielded 130 kg/ha. Highly significant negative correlations occurred each ear
 between initial nematode population densities and seed yield.
 
 
 48                                                     NAL Call. No.: 421 J822
 Cool-season cover crops relay intercropped with cantaloupe: influence on a
 generalist predator, Geocoris punctipes (Hemiptera: Lygaeidae).
 Bugg, R.L.; Wackers, F.L.; Brunson, K.E.; Dutcher, J.D.; Phatak, S.C.
 Lanham, Md. : Entomological Society of America; 1991 Apr.
 Journal of economic entomology v. 84 (2): p. 408-416; 1991 Apr.  Includes
 references.
 
 Language:  English
 
 Descriptors: Georgia; Cucumis melo; Cover crops; Insect control; Intercropping;
 Predators of insect pests; Beneficial insects; Density; Geocoris punctipes
 
 Abstract:  Cool-season cover crops were used in efforts to enhance densities of
 entomophagous insects on relay-intercropped spring plantings of cantaloupe
 (Cucumis melo L. var. reticulatus Seringe). Eight cover-cropping regimes,
 including a weedy fallow control, were tested in a replicated trial. Cover crop
 significantly affected densities of the predominant predator, a bigeyed bug,
 Geocoris punctipes (Say), amid cover crops, on or near cantaloupe plants, and
 on or near sentinel egg masses of fall armyworm, Spodoptera frugiperda (J. E.
 Smith) pinned to cantaloupe leaves. No significant difference was found for
 proportions of egg masses occupied or damaged by predators. For all indices of
 predator abundance and efficiency, absolute responses were highest for the
 plots of subterranean clover (Trifolium subterraneum L., 'Mt. Barker').
 Numbers of G. punctipes per sentinel egg mass were significantly greater for
 the subterranean clover regime than for rye, crimson clover, and a polyculture
 of six cover crops, but were not significantly greater than for 'Vantage' vetch
 or the weedy fallow control plots. Rye showed particularly low densities of G.
 punctipes. Cover crops had no apparent effect on densities of aphids or
 whiteflies (Homoptera: Aphididae, Aleyrodidae) on cantaloupe leaves.
 
 
 49                                                  NAL Call. No.: QK898.N6N52
 Corn growth as affected by nitrogen fixing tree and grass plant materials
 supplemented by P and K fertilizers.
 Tiraa, A.N.; Asghar, M.
 Bangkok, Thailand : Thailand Institute of Scientific and Technological
 Research; 1990 Aug.
 Nitrogen fixing tree research reports v. 8: p. 83-84; 1990 Aug.  Includes
 references.
 
 Language:  English
 
 Descriptors: Zea mays; Leguminosae; Nitrogen fixing trees; Gramineae; Green
 manures; Phosphorus; Fertilizers; Potassium fertilizers; Crop yield; Crop
 residues
 
 
 50                                                      NAL Call. No.: 4 AM34P
 Corn-soybean rotation effects on soil water depletion.
 Copeland, P.J.; Allmaras, R.R.; Crookston, R.K.; Nelson, W.W.
 Madison, Wis. : American Society of Agronomy, [1949-; 1993 Mar.
 Agronomy journal v. 85 (2): p. 203-210; 1993 Mar.  Includes references.
 
 Language:  English
 
 Descriptors: Minnesota; Cabt; Zea mays; Glycine max; Continuous cropping;
 Monoculture; Rotations; Soil water content; Water use efficiency; Plant water
 relations; Crop yield; Evapotranspiration
 
 Abstract:  The positive yield effect of crop rotation may be linked to
 enhanced water uptake and associated efficient use. We hypothesized that a crop
 grown in rotation might deplete soil water more than the same crop grown under
 monoculture because some negative factor associated with monoculture was
 alleviated. Water use efficiency (WUE) might also be improved by rotation. The
 objective of our study was to determine whether altered water uptake or
 altered WUE was associated with the yield increase observed when corn (Zea mays
 L.) and soybean [Glycine max (L.) Merr.] are rotated. A long-term
 corn-soybean rotation experiment was monitored in 1987 and 1988 to determine
 seasonal soil water status to 1.50m. Corn and soybean sequences monitored were:
 monoculture, first-year crop following 5 yrs of the other crop, second-year
 crop following 5 yrs of the other crop, and an annual alteration of the two
 crops. Compared with monoculture, yield was increased up to 30% when corn
 followed soybean and up to 11% when soybean followed corn. Average soil water
 depletion during the season by first-year corn was 16 mm greater than by
 continuous corn. The WUE in corn was related to cropping sequence at a moderate
 level of significance (p = 0.14). Seasonal soil water depletion by soybean was
 not changed by cropping sequence but overall WUE by first-year soybean was
 higher than by continuous soybean (p = 0.05). When there was a period with only
 sparse rainfall in 1988, corn had a greater water depletion than soybean and
 also a deeper zone of depletion. Both crops exhibited a
 greater water depletion when rotated. Frequent rainfall in 1987 sufficient to
 wet the soil below 0.30 m obliterated patterns of depleted soil water.
 Increased water use observed in first-year corn and increased WUE observed in
 first-year soybean (compared to monoculture) in both years suggest that
 rotation allows these crops to increase root surface or root activity and hence
 to improve grain yield.
 
 
 51                                                  NAL Call. No.: QL391.N4J62
 Cotton as a rotation crop for the management of Meloidogyne arenaria and
 Sclerotium rolfsii in peanut.
 Rodriguez-Kabana, R.; Robertson, D.G.; Wells, L.; Weaver, C.F.; King, P.S. Lake
 Alfred, Fla. : Society of Nematologists; 1991 Oct.
 Journal of nematology v. 23 (4,suppl.): p. 652-657; 1991 Oct.  Includes
 references.
 
 Language:  English
 
 Descriptors: Alabama; Gossypium hirsutum; Arachis hypogaea; Meloidogyne
 arenaria; Corticium rolfsii; Rotations; Aldicarb; Pest management
 
 Abstract:  The value of cotton (Gossypium hirsutum cv. Deltapine 90) in
 rotation with peanut (Arachis hypogaea cv. Florunner.) for the management of
 root-knot nematode (Meloidogyne arenaria) and southern blight (Sclerotium
 rolfsii) was studied for 6 years in a field at the Wiregrass Substation in
 southeast Alabama. Peanut yields following either 1 or 2 years of cotton (C-P
 and C-C-P, respectively) were higher than those of peanut monoculture without
 nematicide [P(-)]. At-plant application of aldicarb to continuous peanut
 [P(+)] averaged 22.1% higher yields than those for P(-) over the 6 years of the
 study. The use of aldicarb in cotton and peanut in the C-C-P rotations
 increased yields of both crops over the same rotations without the nematicide.
 When the nematicide was applied to both crops in the C-P rotation, peanut
 yields were increased in only two of the possible three years when peanut was
 planted. Application of aldicarb to cotton only in the C-P rotation did not
 improve peanut yields over those obtained with the rotation without
 nematicide. Juvenile populations of M. arenaria determined at peanut-harvest
 time were lowest in plots with cotton. Plots with C-P or C-C-P had lower
 populations of the nematode than those with either P(-) or P(+). The incidence
 of southern blight (Sclerotium rolfsii) in peanut was lower in plots with the
 rotations than in those with peanut monoculture. Aldicarb application had no
 effect on the occurrence of southern blight.
 
 
 52                                                   NAL Call. No.: S539.5.J68
 Cotton genotype response to green-manured annual legumes.
 Bauer, P.J.; Roach, S.H.; Green, C.C.
 Madison, Wis. : American Society of Agronomy; 1991 Oct.
 Journal of production agriculture v. 4 (4): p. 626-628; 1991 Oct.  Includes
 references.
 
 Language:  English
 
 Descriptors: South Carolina; Gossypium hirsutum; Cultivars; Genotypes; Varietal
 reactions; Trifolium incarnatum; Vicia villosa; Winter; Cover crops; Fallow;
 Incorporation; Crop density; Crop yield; Seeds; Maturation; Temporal variation;
 Biomass production; Desiccation; Paraquat
 
 
 53                                                     NAL Call. No.: SB249.N6
 Cotton lay-by herbicides on wheat, vetch, and winter weeds as cover crops.
 Hurst, H.R.
 Memphis, Tenn. : National Cotton Council of America; 1992.
 Proceedings - Beltwide Cotton Conferences v. 3: p. 1308-1312; 1992.  Paper
 presented at the Cotton Weed Science Research Conference, 1992.  Includes
 references.
 
 Language:  English
 
 Descriptors: Triticum aestivum; Vetch; Gossypium; Cover crops; Herbicides;
 Application methods; Weeds
 
 
 54                                                     NAL Call. No.: SB249.N6
 Cotton response to sorghum and soybean rotations at various nitrogen rates.
 Matocha, J.E.; Barber, K.L.; Hopper, F.L.
 Memphis, Tenn. : National Cotton Council of America, 1991-; 1993.
 Proceedings / v. 3: p. 1373-1375; 1993.  Meeting held January 10-14, 1993, New
 Orleans, Louisiana.  Includes references.
 
 Language:  English
 
 Descriptors: Gossypium; Glycine max; Sorghum; Rotations; Nitrogen fertilizers;
 Application rates
 
 
 55                                                    NAL Call. No.: SB610.W39
 Cover crop management and weed control in corn (Zea mays).
 Johnson, G.A.; DeFelice, M.S.; Helsel, Z.R.
 Champaign, Ill. : The Weed Science Society of America; 1993 Apr.
 Weed technology : a journal of the Weed Science Society of America v. 7 (2): p.
 425-430; 1993 Apr.  Includes references.
 
 Language:  English
 
 Descriptors: Missouri; Cabt; Zea mays; Cover crops; Secale cereale; Vicia
 villosa; Weed control; Setaria faberi; Xanthium strumarium; No-tillage;
 Tillage; Stubble; Crop yield; Grain; Cultural weed control; Chemical control;
 Atrazine; Glyphosate
 
 
 56                                                   NAL Call. No.: S605.5.A43
 Cover crop management effects on soybean and corn growth and nitrogen dynamics
 in an on-farm study.
 Karlen, D.L.; Doran, J.W.
 Greenbelt, Md. : Institute for Alternative Agriculture; 1991.
 American journal of alternative agriculture v. 6 (2): p. 71-82; 1991.
 Includes references.
 
 Language:  English
 
 Descriptors: Iowa; Zea mays; Glycine max; Rotations; Vicia villosa; Secale
 cereale; Avena sativa; Cover crops; Loam soils; Conservation tillage; Ridging;
 Discing; Crop management; Sustainability; Farming systems research; Crop
 residues; Ammonium nitrate; Nitrate nitrogen; Use efficiency; Nutrient
 availability; Nutrient uptake; Seasonal growth; Dry matter accumulation;
 Nitrogen; Nutrient content; Air temperature; Rain; Seasonal variation; Soil
 water content; Water erosion; Erosion control
 
 Abstract:  Combining cover crops and conservation tillage may result in more
 sustainable agricultural production practices. Objectives of this on-farm study
 were 10 quantify effects of cover crops on growth and nitrogen
 accumulation by soybean [Glycine max (L.) Merr.] and corn (Zea mays L.) on a
 Nicollet loam (fine-loamy, mixed, mesic Aquic Hapludoll) near Boone, Iowa. Our
 farmer-cooperator planted soybean in 1988 using ridge tillage into an
 undisturbed strip with a hairy vetch (Vicia villosa L. Roth) cover crop and
 into a strip where previous crop residue and a negligible amount of cover crop
 had been incorporated by autumn and spring disking. In each strip, we
 established four plots for soil and plant measurements. Our cooperator planted
 corn on the same strips in 1989 into a cover crop that consisted of both hairy
 vetch and winter rye (Secale cereale L.). We determined the source of N
 accumulated by the corn by applying 67 kg N/ha of 15N depleted NH4NO3
 fertilizer. In the absence of cover crops, early season soil NO3-N levels in
 the top 30 cm were higher, and corn growth and N accumulation were more rapid.
 At harvest, the corn grain, stover, and cob together accounted for 36 and 39
 percent of the 15N fertilizer for the ridge tillage and disked treatments,
 respectively. We suggest that lower net mineralization of organic matter or
 greater denitrification losses before planting reduced the availability of soil
 N. This created an early season N stress in corn grown with cover crops that
 was not overcome by broadcast fertilizer N applied three weeks after planting.
 Our on-farm research study has helped focus continuing efforts to determine if
 non-recovered fertilizer N is being immobilized in microbial biomass, lost by
 denitrification, or leached below the plant root zone.
 
 
 57                                                    NAL Call. No.: 100 M69MI
 Crimson clover benefits soil, crops, and producers.
 Broadway, R.
 Mississippi State, Miss. : The Station; 1991 Dec.
 MAFES research highlights - Mississippi Agricultural and Forestry Experiment
 Station v. 54 (12): p. 7; 1991 Dec.
 
 Language:  English
 
 Descriptors: Trifolium incarnatum; Nitrogen; Nitrogen fixation; Cover crops;
 Zea mays; Production costs; No-tillage
 
 
 58                                                      NAL Call. No.: 4 AM34P
 Crimson clover management to enhance reseeding and no-till corn grain
 production.
 Ranells, N.N.; Wagger, M.G.
 Madison, Wis. : American Society of Agronomy; 1993 Jan.
 Agronomy journal v. 85 (1): p. 62-67; 1993 Jan.  Includes references.
 
 Language:  English
 
 Descriptors: Zea mays; Cover crops; Trifolium incarnatum; No-tillage; Resowing;
 Strip cropping; Row orientation; Crop yield; Grain; Growth rate; Soil water
 content
 
 Abstract:  Economic savings and increased legume-N use efficiency may result
 from natural reseeding of winter annual legume cover crops. A 3-yr experiment
 was conducted on a Cecil fine sandy loam (clayey, kaolinitic, thermic Typic
 Kanhapludult) to examine the effects of crimson clover (Trifolium incarnatum
 L.) strip desiccation width (25, 50, and 75% of row area) and orientation
 (parallel or perpendicular to plant row) on soil water depletion, corn (Zea
 mays L.) growth and grain yield, and clover reseeding. Additional treatments
 included early desiccation (25% parallel strip 2 wk before corn planting),
 annual seeding (complete desiccation at corn planting), and mechanical
 disruption of clover growth by the no-tillage planter. Early-season soil water
 was lower in annual seeded plots compared to the 25% strip treatments each
 year, however, soil water was limiting in only one of 3 yr. Crimson clover
 successfully reseeded in all strip treatments each year, with dry matter
 production ranging from 3.0 to 5.2 Mg ha-1 in 1990 and from 3.9 to 5.2 Mg ha-1
 in 1991. Nitrogen content of reseeded crimson clover biomass ranged from 86 to
 134 kg ha-1 in 1990 and 93 to 111 kg ha-1 in 1991. Corn grain yield was only
 marginally affected by clover strip management in two out of 3 yr. Results
 suggest that under adequate moisture conditions a 50% desiccated strip has the
 potential to maximize clover N contribution. However, a 75% strip-width can
 minimize potential competition with corn for water and reduce physical
 impedance of the clover cover crop on corn growth.
 
 
 59                                                   NAL Call. No.: S539.5.J68
 Crimson clover reseeding potential as affected by s-triazine herbicides.
 Ranells, N.N.; Wagger, M.G.
 Madison, Wis. : American Society of Agronomy; 1993 Jan.
 Journal of production agriculture v. 6 (1): p. 90-93; 1993 Jan.  Includes
 references.
 
 Language:  English
 
 Descriptors: Trifolium incarnatum; Cover crops; Resowing; Atrazine; Cyanazine;
 Simazine; Residual effects; Application date; Crop growth stage
 
 
 60                                                      NAL Call. No.: 4 AM34P
 Critical phosphorus levels for corn and cowpea in a Brazilian Amazon Oxisol.
 Smyth, T.J.; Cravo, M.S.
 Madison, Wis. : American Society of Agronomy; 1990 Mar.
 Agronomy journal v. 82 (2): p. 309-312; 1990 Mar.  Includes references.
 
 Language:  English
 
 Descriptors: Brazil; Zea mays; Vigna unguiculata; Rotations; Fertilizer
 placement; Phosphorus fertilizers; Oxisols; Fertilizer requirement
 determinatio; Nutrient availability
 
 Abstract:  Phosphorus soil test interpretations in the Brazilian Amazon
 currently do not account for differences in P requirements among crops and lack
 information on the changes in available soil P per unit of applied
 fertilizer P. A long-term P experiment in a Xanthic Hapludox near Manaus,
 Brazil was used to determine soil and leaf P critical levels for corn (Zea mays
 L.) and cowpea (Vigna anguiculata L.). A total of six corn crops were planted
 in annual rotation with five crops of cowpea during five consecutive years.
 Critical levels were established by a segmented linear regression, a linear
 plateau, of relative crop yields on soil test or leaf P concentrations for each
 crop species. Mehlich 1 (1:10) critical P levels were 6 and 8 mg kg-1 for corn
 and cowpea, respectively. Relationships between soil test P and crop yields
 were similar for fertilizer P placement as either broadcast and/or frequent
 bands. Fertilizer P required to raise the initial Mehlich 1 soil P to the
 critical levels were 41 and 60 kg P ha-1 for corn and cowpea, respectively.
 Higher amounts of P were extracted by Bray 1 than by Mehlich 1, but both
 extractants were effective in relating available soil P to yield and applied
 fertilizer P. Critical foliar P concentrations for corn and cowpea were 1.6 and
 1.8 g kg-1, respectively. Higher soil and leaf P critical levels for cowpea
 relative to corn were attributed to greater P requirements for plants depending
 on symbiotic N2 fixation for their N supply.
 
 
 61                                                     NAL Call. No.: 56.9 SO3
 Crop and tillage rotations: grain yield, residue cover, and soil water.
 Wagger, M.G.; Denton, H.P.
 Madison, Wis. : The Society; 1992 Jul.
 Soil Science Society of America journal v. 56 (4): p. 1233-1237; 1992 Jul.
 Includes references.
 
 Language:  English
 
 Descriptors: Zea mays; Glycine max; Continuous cropping; Rotations; Tillage;
 No-tillage; Seasonal variation; Coastal plain soils; Soil types
 (physiographic); Upland soils; Comparisons; Soil water content; Crop yield;
 Grain; Crop residues; Coverage
 
 Abstract:  Information regarding crop yield response for different tillage and
 rotation systems is needed to determine regional or local suitability for a
 given production system. Our objective was to determine the effects of
 continuous and alternating tillage sequences in corn (Zea mays L.) monoculture
 and corn-soybean [Glycine max (L.) Merr.] rotation on residue cover, soil
 water, and grain yield. Continuous conventional tillage (CT), continuous
 no-tillage (NT), or CT and NT alternating every other year were evaluated
 during a 5-yr period on a Rion (fine-loamy, mixed, thermic Typic
 Hapludult)-Pacolet (clayey, kaolinitic, thermic Typic Kanhapludult) sandy clay
 loam complex at a Piedmont location and an Eunola sandy loam (fine-loamy,
 siliceous, thermic Aquic Hapludult) at a Coastal Plain location. The 5-yr
 overage NT corn grain yield was 27% (1.15 Mg ha-1) higher than CT at the
 Piedmont location, but only 4% (0.32 Mg ha-1) higher at the Coastal Plain
 location. Continuous NT at the Piedmont location also resulted in higher corn
 yields 2 out of 4 yr compared with NT following CT. The increase in corn yield
 with NT was associated with greater soil water availability, primarily
 attributed to surface residue cover from corn stover fostering greater
 infiltration on a crust-prone soil. Soybean yield during the 5-yr period was 5%
 higher with NT at the Piedmont location and unaffected by tillage at the
 Coastal Plain location. In general, crop rotation had no effect on corn yield
 at either location. Results indicate that continuous NT should be the system of
 choice on this upland Piedmont soil.
 
 
 62                                                   NAL Call. No.: S539.5.J68
 Crop and weed management effects on weed populations in a short-term
 corn-corn-peanut rotation.
 Johnson, W.C. III; Cardina, J.; Mullinix, B.G. Jr
 Madison, Wis. : American Society of Agronomy; 1992 Oct.
 Journal of production agriculture v. 5 (4): p. 566-570; 1992 Oct.  Includes
 references.
 
 Language:  English
 
 Descriptors: Georgia; Zea mays; Arachis hypogaea; Rotations; Crop management;
 Pest management; Weed control; Weeds; Populations; Species diversity; Crop
 yield
 
 
 63                                                  NAL Call. No.: S592.7.A1S6
 Crop mulch effects on Rhizoctonia soil infestation and disease severity in
 conservation-tilled cotton.
 Rickerl, D.H.; Curl, E.A.; Touchton, J.T.; Gordon, W.B.
 Exeter : Pergamon Press; 1992 Jun.
 Soil biology and biochemistry v. 24 (6): p. 553-557; 1992 Jun.  Includes
 references.
 
 Language:  English
 
 Descriptors: Alabama; Gossypium; Vicia villosa; Trifolium incarnatum; Mulches;
 Rotations; Fallow; Rhizoctonia solani; Fungal diseases; Conservation tillage;
 Crop damage; Emergence; Survival; Soil fungi; Infestation; Population density;
 Virulence; Inoculum density; Crop residues; Seasonal variation; Soil
 temperature; Paleudults; Coastal plain soils; Sandy loam soils
 
 Abstract:  Vetch (Vicia villosa Roth), clover (Trifolium incarnatum L.), and
 fallow (no winter cover crop) were used as mulch crops preceding cotton
 planted in a conservation tillage system. In field tests, cotton emergence and
 survival were reduced in legume mulches with significant differences at the
 second planting in 1985. Assessments of Rhizoctonia soil infestation estimated
 using a modified stem trap baiting procedure, indicated higher amounts of
 Rhizoctonia in cotton following legume crops than in cotton following fallow.
 In greenhouse studies, comparisons of warm (29 +/- 2 degrees C day and 21 +/-2
 degrees C night) and cool (29 +/- 2 degrees C day and 10 +/- 2 degrees C night)
 temperature regimes imposed on the clover, vetch and fallow treatments,
 demonstrated that the cool temperature regime significantly reduced emergence
 and survival of cotton seedlings. However, there was no interaction of
 cropping treatments (legume cropped or fallowed treatments with temperature
 regimes). Cotton seedling disease severity in the greenhouse assay of
 field-collected soil samples showed a significant interaction among year, soil
 treatment and temperature.
 
 
 64                                                     NAL Call. No.: 23 AU792
 Crop production on duplex soils in south-eastern Australia.
 Gardner, W.K.; Fawcett, R.G.; Steed, G.R.; Pratley, J.E.; Whitfield, D.M.; Van
 Rees, H.
 East Melbourne : Commonwealth Scientific and Industrial Research Organization;
 1992.
 Australian journal of experimental agriculture v. 32 (7): p. 915-927. maps;
 1992.  Special issue: Crop production on duplex soils.  Literature review.
 Includes references.
 
 Language:  English
 
 Descriptors: New South Wales; South australia; Victoria; Cereals; Grasses;
 Legumes; Crop production; Duplex soils; Losses from soil; Soil degradation;
 Waterlogging; Rotations; Subsurface drainage; Tillage; Literature reviews
 
 
 65                                                    NAL Call. No.: 464.8 P56
 Crop rotation and nematicide effects on the frequency of Meloidogyne spp. in a
 mixed population.
 Fortnum, B.A.; Currin, R.E. III
 St. Paul, Minn. : American Phytopathological Society; 1993 Mar.
 Phytopathology v. 83 (3): p. 350-355; 1993 Mar.  Includes references.
 
 Language:  English
 
 Descriptors: South Carolina; Nicotiana tabacum; Meloidogyne incognita;
 Meloidogyne arenaria; Plant parasitic nematodes; Nematode control; Rotations;
 1,3-dichloropropene; Crop production; Crop yield
 
 Abstract:  The effects of crop rotation and nematicide 1,3-dichloropropene
 (1,3-D) on the relative frequency of M. incognita race 3 and M. arenaria race 2
 and on tobacco yields were determined in a sandy loam soil. Cropping
 sequences altered the species composition and population densities of
 Meloidogyne spp. and increased tobacco yields. M. incognita predominated when
 cotton or corn preceded tobacco; M. arenaria predominated when soybean or
 peanut preceded tobacco. Fumigation of tobacco land increased the density of M.
 arenaria compared to M. incognita. The effects of a previous crop on
 tobacco yields varied in successive years. Cotton, corn, peanut, sorghum, or
 rye-fallow preceding tobacco in 1985 enhanced yields compared to yields when
 soybean preceded tobacco. Rye-fallow preceding tobacco in 1987 resulted in
 greater tobacco yields than when tobacco was preceded by soybean, corn, cotton,
 sorghum or peanut. Application of 1,3-D increased tobacco yields, except when
 preceded by rye-fallow.
 
 
 66                                                      NAL Call. No.: 4 AM34P
 Crop rotation and tillage effects on corn growth and soil structural
 stability.
 Raimbault, B.A.; Vyn, T.J.
 Madison, Wis. : American Society of Agronomy; 1991 Nov.
 Agronomy journal v. 83 (6): p. 979-985; 1991 Nov.  Includes references.
 
 Language:  English
 
 Descriptors: Ontario; Zea mays; Rotations; Medicago sativa; Hordeum vulgare;
 Triticum aestivum; Trifolium pratense; Continuous cropping; Sequential
 cropping; Intercropping; Tillage; Minimum tillage; Crop yield; Grain; Growth
 rate; Soil structure; Aggregates; Stability; Long term experiments
 
 Abstract:  Increasing concerns about soil degradation with continuous corn (Zea
 mays L.) production and a scarcity of scientific information regarding corn
 grown in rotation with the diversity of crops produced in Ontario, prompted a
 long term study on the effect of various crop rotations and their interaction
 with two tillage systems on corn growth and soil structure. Eight rotations
 were established in 1980 which included continuous corn, six
 rotations comprised of 2 yr of corn following 2 yr of another crop or crop
 sequence, and continuous alfalfa (Medicago sativa L.). Each rotation was
 divided into either conventional tillage (fall moldboard plow) or minimum
 tillage (fall chisel plow). First-year corn grown in rotation yielded 3.9% more
 than continuous corn for conventional tillage and 7.9% more than
 continuous corn for minimum tillage. These corn responses to rotation were
 smaller than most of those reported in the literature. When barley (Hordeum
 vulgare L.) or wheat (Triticum aestivum L.) were the preceding crops,
 interseeding red clover (Trifolium pratense L.) increased first year corn
 yields only on conventionally tilled plots. Corn plant development was
 consistently slower with minimum tillage compared to conventional tillage.
 Yields were significantly lower with minimum tillage for continuous corn and
 where corn followed wheat interseeded with red clover. Little or no response to
 rotation was observed in second-year corn. The seedbed with continuous corn had
 a lower proportion of fine aggregates compared to corn grown in rotation. In
 most years soil aggregate stability was highest under continuous alfalfa and
 including a legume (whether alfalfa or interseeded red clover) in the rotation
 improved aggregate stability compared to continuous corn.
 
 
 67                                                     NAL Call. No.: 56.9 SO3
 Crop rotation and tillage effects on soil organic carbon and nitrogen.
 Havlin, J.L.; Kissel, D.E.; Maddux, L.D.; Claassen, M.M.; Long, J.H.
 Madison, Wis. : The Society; 1990 Mar.
 Soil Science Society of America journal v. 54 (2): p. 448-452; 1990 Mar.
 Includes references.
 
 Language:  English
 
 Descriptors: Kansas; Sorghum bicolor; Glycine max; Zea mays; Rotations;
 Tillage; No-tillage; Continuous cropping; Carbon; Nitrogen; Organic matter in
 soil; Ammonium nitrate; Crop residues; Surface layers; Soil depth
 
 Abstract:  Sustaining or increasing soil productivity depends in part on soil
 and crop management practices that maintain or increase soil organic matter.
 This study was conducted to determine the effects of tillage crop rotation, and
 fertilizer N on soil organic C and N. Two long-term tillage/rotation
 studies and one long-term rotation/N-rate study were conducted on eastern
 Kansas soils. Soils were sampled from conventional (CT) and no-tillage (NT)
 treatments applied to continuous sorghum [Sorghum bicolor (L.) Moench] (S/S),
 continuous soybean [Glycine max (L.) Merr.] (B/B), and sorghum-soybean (S/B)
 rotations in the tillage/rotation studies and from the 0 and 252 kg N ha-1
 treatments on continuous corn (Zea mays L.) (C/C), B/B, and corn-soybean (C/B)
 rotations in the rotation/N-rate study. Organic C and N were determined on
 soils sampled at depths of 0 to 2.5, 2.5 to 7.5, 7.5 to 15, and 15 to 30 cm.
 Compared with CT, NT had greater organic C and N contents. Compared with B/B,
 S/B and S/S increased organic C and N under NT and, to a lesser extent, under
 CT (at 0-2.5-cm depth). Increases in organic C and N with NT compared with CT
 and with sorghum rotations compared with B/B were directly related to the
 quantity of residue produced and left on the soil surface (S/S > S/B / > B/B).
 Fertilizer N increased soil organic C and N only slightly. Crop management
 systems that include rotations with high residue-producing crops and
 maintenance of surface residue cover with reduced tillage result in greater
 soil organic C and N, which may improve soil productivity.
 
 
 68                                                NAL Call. No.: aHD1401.A2U52
 Crop rotations: still the norm.
 Foulke, J.
 Washington, D.C. : The Service; 1990 May.
 Farmline - U.S. Department of Agriculture, Economic Research Service v. 11 (5):
 p. 4-6; 1990 May.
 
 Language:  English
 
 Descriptors: U.S.A.; Maize; Wheat; Soybeans; Rice; Cotton; Potatoes; Rotations;
 Farmland; Farm management; Soil conservation
 
 
 69                                                  NAL Call. No.: 290.9 AM32T
 Crop rotations with full and limited irrigation and dryland management.
 Schneekloth, J.P.; Klocke, N.L.; Hergert, G.W.; Martin, D.L.; Clark, R.T. St.
 Joseph, Mich. : American Society of Agricultural Engineers; 1991 Nov.
 Transactions of the ASAE v. 34 (6): p. 2372-2380; 1991 Nov.  Includes
 references.
 
 Language:  English
 
 Descriptors: Nebraska; Triticum aestivum; Zea mays; Glycine max; Irrigation;
 Rotations; Dry farming; Evapotranspiration; Water management
 
 Abstract:  Irrigated cropping systems need to maximize the economic value of
 both rainfall and irrigation water, especially in areas of declining
 groundwater. This study compared water management systems in a winter wheat
 (Triticum aestivum, L.)-corn (Zea mays, L.)-soybean (Glycine max, L.) (W-C-S)
 and continuous corn (CC) rotation in west central Nebraska for dryland, limited
 irrigation (150 mm/yr), and full irrigation. Crop yield, evapotranspiration,
 and soil water storage were determined from field studies conducted at North
 Platte, Nebraska, on a Cozad silt loam (Fluventic
 Haplustoll) soil. Dryland corn used 21.5% more evapotranspiration (ET) in the
 W-C-S rotation compare to CC. ET for the limited and full irrigation com was
 4.6% and 4.9% more for the W-C-S rotation compared to the CC and was
 statistically significant at the P > 0.08 level. Water use efficiency, defined
 by the slope of the linear relationship between grain yield and ET
 (differential Y differential ET-1), was the same for corn in the W-C-S and CC
 rotations. Corn grain yield response to irrigation and ET was more than the
 yield response of winter wheat and soybean. The W-C-S rotation increased com
 grain yields in two out of three years at this location for dryland management
 and increased the seasonal ET of corn compared to continuous corn. Full
 irrigation management did not consistently increase winter wheat and soybean
 grain yields above the limited irrigation treatments. Soil water storage for
 the full irrigation management was greatly reduced compared to dryland and
 limited irrigation management for both rotations.
 
 
 70                                                      NAL Call. No.: 4 AM34P
 Crop sequence affects nutrient composition of corn and soybean grown under high
 fertility.
 Copeland, P.J.; Crookston, R.K.
 Madison, Wis. : American Society of Agronomy; 1992 May23.
 Agronomy journal v. 84 (3): p. 503-509; 1992 May23.  Includes references.
 
 Language:  English
 
 Descriptors: Minnesota; Zea mays; Glycine max; Rotations; Plant analysis;
 Nutrient content; Crop yield; Responses; Growth stages; Soil chemistry;
 Nutrients
 
 Abstract:  Although crop rotation may change soil mineral status, particularly
 N, there may also be a rotation effect beyond that which can be explained by
 soil mineral status alone. Research has shown that leaf mineral-composition can
 vary between crop sequences at high fertilizer levels. We hypothesized that the
 rotation effect observed in long-term sequences of corn (Zea mays L.) and
 soybean [Glycine max (L.) Merr.] might be due to an increased nutrient
 concentration, not just an increased accumulation. A corn-soybean rotation
 study in Minnesota managed at high nutrient fertility was used to test our
 hypothesis. The high management level was appraised by soil test levels. Corn
 and soybean sequences evaluated were monoculture, first year, second year, and
 annually-alternated. These crop sequences were evaluated for their effects on
 plant nutrient concentration, accumulation, or both. The growth stage at which
 differences in plant nutrient concentration or accumulation might affect final
 yield was also evaluated. A positive effect of rotation on yield was observed
 in both crops. Shoot concentrations and total accumulations of N, P, and K were
 higher in first year corn compared to monoculture, suggesting that the
 increased corn yield associated with rotation may have been due to a general
 improvement in plant nutrition. Cropping sequence had less of an effect on
 soybean nutrient concentration than corn. Nutrient accumulation in soybean was
 not generally affected by crop sequence.
 
 
 71                                                    NAL Call. No.: SB599.C35
 Crop sequences and tillage practices in relation to diseases of winter wheat in
 Ontario.
 Sutton, J.C.; Vyn, T.J.
 Guelph, Ont. : Canadian Phytopathological Society; 1990 Dec.
 Canadian journal of plant pathology; Revue Canadienne de phytopathologie v. 12
 (4): p. 358-368; 1990 Dec.  Includes references.
 
 Language:  English
 
 Descriptors: Ontario; Triticum aestivum; Rotations; Glycine max; Zea mays;
 Hordeum vulgare; Medicago sativa; Continuous cropping; No-tillage; Minimum
 tillage; Tillage; Disease prevalence; Incidence; Leptosphaeria nodorum;
 Pyrenophora tritici-repentis; Mycosphaerella graminicola; Gaeumannomyces
 graminis; Infections; Inoculum density; Crop yield; Crop residues
 
 
 72                                                     NAL Call. No.: 56.9 SO3
 Crop species, amendment, and water quality effects on selected soil physical
 properties.
 Bauder, J.W.; Brock, T.A.
 Madison, Wis. : The Society; 1992 Jul.
 Soil Science Society of America journal v. 56 (4): p. 1292-1298; 1992 Jul.
 Includes references.
 
 Language:  English
 
 Descriptors: Montana; Saline soils; Sodic soils; Reclamation; Irrigated soils;
 Crops; Species; Gypsum; Phosphogypsum; Magnesium chloride; Irrigation water;
 Water quality; Bulk density; Soil density; Porosity; Pore size distribution;
 Infiltration
 
 Abstract:  Saline and sodic soils have developed in some irrigated areas of
 Montana. Cropping systems that promote maximum efficacy of surface-applied
 amendments for reclamation need to be identified. Effects of crop species,
 amendment, and water quality on alteration of selected physical properties of a
 Haverson silty clay (fine-loamy, mixed [calcareous], mesic Ustic
 Torrifluvent) were compared. Crops grown in lysimeters and compared with a
 noncropped control were alfalfa (Medicago sativa L.), barley (Hordeum vulgare
 L.), and sorghum sundangrass [Sorghum bicolor (L.) Moench-S. X drummondii
 (Steudel) Millsp. & Chase], commonly referred to as sordan. Soil amendments
 included a check, gypsum (CaSO4.2H2O), phosphogypsum (CaSO4.2H2O with < 1%
 [w/w] P), and MgCl2. Lysimeters were irrigated with water having either a total
 dissolved solids (TDS) concentration of 0.75 g L-1 and a sodium
 adsorption ratio (SAR) of 1.15 or TDS of 1.65 g L-1 and SAR of 7.01 until three
 barely crops were successively grown. The presence of a crop caused a
 significant increase in bulk density in all lysimeters and a significant
 decrease in total porosity, compared with the uncropped control treatments.
 Barley caused the greatest decrease in total porosity, followed by alfalfa,
 then sordan. Total porosity decreased nearly 0.1 m3 m-3. The result was a
 significant increase in number of micropores (< O.149 X 10(-2) mm radius) and a
 disproportionately greater decrease in number of macropores (> 1.49 X 10(-2) mm
 radius). Soil water release characteristics differed among the different crop
 treatments. Neither amendment treatment nor irrigation water quality had a
 significant effect on either porosity, pore-size distribution, or bulk
 density. Results of this study indicate that crop selection and rotation may
 affect the significance of surface-applied amendments used for reclamation and
 leaching of Na- and salt-affected soils.
 
 
 73                                                     NAL Call. No.: 56.9 SO3
 Cropping frequencies to sustain long-term conservation tillage systems.
 Langdale, G.W.; Wilson, R.L. Jr; Bruce, R.R.
 Madison, Wis. : The Society; 1990 Jan.
 Soil Science Society of America journal v. 54 (1): p. 193-198; 1990 Jan.
 Includes references.
 
 Language:  English
 
 Descriptors: Double cropping; Continuous cropping; Rotations; Minimum tillage
 systems; Glycine max; Sorghum bicolor; Triticum aestivum; Annual field crops;
 Crop yield; Physico-chemical properties of soil; Depth
 
 Abstract:  Conservation tillage technologies are essential to develop
 long-term alternative agriculture approaches to protect the nation's
 resources. This study was conducted to develop long-term multiple cropping
 systems to sustain conservation crop production. Soybean [Glycine max (L.)
 Merrill] and grain sorghum [Sorghum bicolor (L) Moench] cropping sequences
 following wheat (Triticum aestivum (L.) grain harvest were studied at three
 tillage-intensity levels on a Cecil sandy loam (clayey, kaolinitic, thermic
 Typic Hapludult) soil. During the first 4-yr crop rotation cycle, coulter in-
 row chisel (MT) planted grain sorghum produced significantly more grain than
 either coulter (NT) or disk harrow (CT) planted (4.89 vs. 4.58 and 4.39 Mg
 ha-1), without a crop-rotation response. In the second 4-yr cycle, the sorghum
 grain yields declined NT > MT > CT (5.14 > 4.74 > 4.40 Mg ha-1)
 significantly with each increase in tillage-intensity level. Soybean responded
 consistently and significantly to high-frequency (1:1) rotation with grain
 sorghum. These responses to rotation with grain sorghum become less important
 to conservation tillage systems when favorable rainfall distributions permit
 grain yields that range between 2.00 and 3.50 Mg ha-1. Wheat yields increased
 significantly following soybean (first rotation cycle) until take-all
 (Graeumannomyces graminis) became epidemic. Elucidation of significant grain
 sorghum responses to in-row chisel and coulter conservation tillage during the
 first and second crop-rotation cycles, respectively, requires additional
 research that focuses on characterization of temporal changes in the soil
 environment. Rotation of both cool- and warm-season crops is necessary to
 sustain long-term conservation tillage.
 
 
 74                                                     NAL Call. No.: S590.C63
 Cropping rotations: effect on aggregate stability and biological activity.
 Arrigo, N.M.; Palma, R.M.; Conti, M.E.; Costantini, A.O.
 New York, N.Y. : Marcel Dekker; 1993.
 Communications in soil science and plant analysis v. 24 (17/18): p. 2441-2453;
 1993.  Includes references.
 
 Language:  English
 
 Descriptors: Triticum aestivum; Glycine max; Zea mays; Helianthus annuus;
 Rotations; Aggregates; Stability; Biological activity in soil; Bulk density;
 Soil organic matter; Carbon
 
 
 75                                                   NAL Call. No.: S539.5.J68
 Cropping systems for clay soils: irrigated and nonirrigated soybean rotated
 with corn and sorghum.
 Heatherly, L.G.; Wesley, R.A.; Elmore, C.D.
 Madison, Wis. : American Society of Agronomy; 1992 Apr.
 Journal of production agriculture v. 5 (2): p. 248-253; 1992 Apr.  Includes
 references.
 
 Language:  English
 
 Descriptors: Mississippi; Glycine max; Zea mays; Sorghum bicolor; Triticum
 aestivum; Crop yield; Seeds; Grain; Rotations; Continuous cropping;
 Monoculture; Irrigated conditions; Dry farming; Clay soils; Double cropping
 
 
 76                                                     NAL Call. No.: 56.9 SO3
 Cropping systems on mycorrhizal colonization, early growth, and phosphorus
 uptake of corn.
 Vivekanandan, M.; Fixen, P.E.
 Madison, Wis. : The Society; 1991 Jan.
 Soil Science Society of America journal v. 55 (1): p. 136-140; 1991 Jan.
 Includes references.
 
 Language:  English
 
 Descriptors: South Dakota; Zea mays; Glycine max; Vesicular arbuscular
 mycorrhizas; Roots; Infection; Nutrient uptake; Phosphorus; Growth rate; Crop
 growth stage; Rotations; Fallow systems; Continuous cropping; Plowing; Ridging
 
 Abstract:  A field study was established in 1986 on a Viborg silty clay loam
 (fine-silty, mixed, mesic Pachic Haplustoll) soil in eastern South Dakota. The
 objectives were to quantify the influence of crop rotation, tillage, and
 residual P (254 kg P ha-1 applied in fall 1985) on the incidence of vesicular-
 arbuscular mycorrhizae (VAM) of corn (Zea mays L.) and to define the
 relationship between VAM colonization, early growth response to P, and early P
 uptake of corn. Plant and root samples were collected periodically from plots
 that varied in tillage and previous crop. Crop rotation and tillage influenced
 the early growth and P uptake of corn. Large differences in early growth
 response to P were observed among cropping systems. Average relative growth
 response as compared with the check during both years ranged from 360% for the
 moldboard (MP) corn-fallow rotation to 7% for the ridge-plant (RP) corn-soybean
 (Glycine max [L].) Merr.) rotation. Early dry-matter production and P uptake in
 the check plots were highest in the RP corn-soybean system and lowest in the MP
 corn-fallow system. Generally, VAM colonization rates were significantly higher
 (P less than or equal to 0.10) in the RP systems than in the MP systems.
 Considerable reduction in VAM colonization rates were found with P
 fertilization (P less than or equal to 0.01) in all cropping systems. An
 inverse relationship was measured between VAM colonization and relative early
 growth response to P (Y = 647.0 - 49.4X + 0.97X2; R2 = 0.92; Y = growth
 response in percent, X = percent root length colonized). Considering early dry-
 matter production, P uptake, and mycorrhizal association the RP corn-soybean
 system appears to provide a good environment for P nutrition of corn during
 early vegetative growth.   
 
 
 77                                                    NAL Call. No.: S631.F422
 The current and residual value of superphosphate for lupins grown in rotation
 with oats and wheat on a deep sandy soil.
 Bolland, M.D.A.
 Dordrecht : Kluwer Academic Publishers; 1992 Jun.
 Fertilizer research v. 31 (3): p. 319-329; 1992 Jun.  Includes references.
 
 Language:  English
 
 Descriptors: Avena sativa; Triticum aestivum; Superphosphates; Lupins;
 Rotations
 
 Abstract:  In a field experiment on a deep pale-yellow sand in a 600 mm per
 annum rainfall Mediterranean environment of south-western Australia, six
 levels of phosphorus (P) as superphosphate (O up to 546 kg P ha-1) were
 applied once only, to the soil surface, before sowing lupins (Lupinus
 angustifolius). The lupins were grown in a continuous arable cropping rotation
 with, in successive years, oats (Avena sativa), wheat (Triticum aestivum),
 lupins. Five such rotations were started in the experiment from 1985 to 1989.
 The experiment continued until the end of 1990. The relationship between lupin
 seed (grain) yields and the level of P applied was measured in the year of P
 application for five successive years (1985 to 1989). The relationship had the
 same general form but it varied between years, largely due to different
 maximum yields (yield plateaux) in each year. The residual value of
 superphosphate applied three years previously was measured for lupins on two
 occasions (1988 and 1989) relative to superphosphate applied in the current
 year. The residual values was different in the two years. The superphosphate
 applied three years previously was about 30% as effective as freshly applied
 superphosphate in 1988, and 12% as effective in 1989. At each harvest, the
 relationship between grain yield and the P concentration in the grain differed
 for different species. However, for each species at each harvest, the
 relationship was similar regardless of when the P was applied in the previous
 years. Thus each species had the same internal efficiency of P use curve, and
 yields varied only with P concentration in tissue. Bicarbonate-extractable soil
 P was determined on soil samples taken in mid-July of 1989 and 1990. These soil
 test values were related to grain yields at harvest. The
 relationship between yield and soil test values had the same general form but
 varied for different species within years and for each species between years.
 It also varied for each species within years depend
 
 
 78                                                    NAL Call. No.: S612.I756
 Cyclic and blending strategies for using nonsaline and saline waters for
 irrigation.
 Bradford, S.; Letey, J.
 Berlin, W. Ger. : Springer International; 1992.
 Irrigation science v. 13 (3): p. 123-128; 1992.  Includes references.
 
 Language:  English
 
 Descriptors: Medicago sativa; Zea mays; Gossypium hirsutum; Rotations;
 Continuous cropping; Salt tolerance; Irrigation; Blending; Cycling; Irrigation
 water; Saline water; Salinity; Water quality; Simulation models; Dry matter
 accumulation; Electrical conductivity; Mathematical models
 
 Abstract:  Large quantities of saline water frequently exist in irrigated areas
 of the world. Various strategies have been proposed to use these saline waters.
 Blending involves mixing saline water with good quality water to an acceptable
 salinity and then using this water to irrigate crops. The cyclic strategy uses
 waters of various salinities separately either during one season or in a crop
 rotation as a function of the crop's salt tolerance. A
 multi-seasonal transient state model, known as the modified van
 Genuchten-Hanks model, was used to investigate the effects of cyclic or
 blending application of irrigation waters of two salinity levels on alfalfa
 (Medicago sativa L.), and on a corn (Zea mays L.) and cotton (Gossypium
 hirsutum L.) crop rotation. Simulated alfalfa yields were similar for the
 cyclic and blending strategies that applied the same amount of salt and water.
 The cyclic strategy produced higher simulated yields of salt-sensitive corn
 than the blending strategy, whereas the simulated salt-tolerant cotton yield
 was not affected by the two strategies. The beneficial effects of the cyclic
 strategy on corn production decreased under deficit irrigation.
 
 
 79                                                   NAL Call. No.: QH84.8.B46
 Denitrifying ability of indigenous strains of Bradyrhizobium japonicum
 isolated from fields under paddy-upland rotation.
 Asakawa, S.
 Berlin : Springer International; 1993.
 Biology and fertility of soils v. 15 (3): p. 196-200; 1993.  Includes
 references.
 
 Language:  English
 
 Descriptors: Japan; Glycine max; Oryza sativa; Alcaligenes; Bradyrhizobium
 japonicum; Denitrification; Rotations; Soil bacteria; Site factors
 
 
 80                                                     NAL Call. No.: 1.9 P69P
 Density of sclerotia of Rhizoctonia solani and incidence of sheath blight in
 rice fields in Mississippi.
 Damicone, J.P.; Patel, M.V.; Moore, W.F.
 St. Paul, Minn. : American Phytopathological Society; 1993 Mar.
 Plant disease v. 77 (3): p. 257-260; 1993 Mar.  Includes references.
 
 Language:  English
 
 Descriptors: Mississippi; Oryza sativa; Glycine max; Rotations; Rhizoctonia
 solani; Blight; Disease surveys; Sclerotia; Inoculum density; Incidence;
 Correlation; Epidemiology; Disease models
 
 
 81                                                     NAL Call. No.: 56.9 So3
 Dentrification and mineralization in soil amended with legume, grass, and corn
 residues.
 McKenney, D.J.; Wang, S.W.; Drury, C.F.; Findlay, W.I.
 Madison, Wis. : Soil Science Society of America; 1993 Jul.
 Soil Science Society of America journal v. 57 (4): p. 1013-1020; 1993 Jul.
 Includes references.
 
 Language:  English
 
 Descriptors: Clay loam soils; Vicia villosa; Trifolium pratense; Lolium
 multiflorum; Phalaris arundinacea; Zea mays; Crop residues; Incorporation;
 Denitrification; Nitrate; Reduction; Nitrogen; Mineralization; Immobilization;
 Ammonium; Nitrogen cycle; Anaerobic conditions
 
 Abstract:  Since cover crops and intercrops are increasingly used to reduce
 soil erosion and N loss and provide efficient N utilization, it is important to
 evaluate the consequences of crop residue to N cycling processes. The
 objectives of this study were to determine effects of incorporating hairy vetch
 (HV, Vicia villosa Roth subsp. villosa), red clover (RC, Trifolium
 pratense L.), annual ryegrass (ARG, Lolium multiflorum Lam.), reed canarygrass
 (RCG, Phalaris arundinacea L.), and corn (Zea mays L.) residues on
 denitrification, dissimilatory NO3(-) reduction, and N
 mineralization-immobilization in a Brookston clay loam (fine-loamy, mixed,
 mesic Typic Argiaquoll). A gas flow system was used with 5 or 10 g residue kg-1
 amended soil. With only anaerobic incubation, all residues stimulated
 denitrification about equally with net NO and N2O production rates two to three
 times greater than in the control soil. Ammonium accumulation over the 48-h
 anaerobic period was 5 to 11 mg N kg-1. When a 5-d aerobic incubation preceeded
 the anaerobic phase, losses of NO + N2O amounted to 5 to 17 times that in the
 control soil during the anaerobic phase. These losses were: 59.4, 47.1, 25.1,
 24.4, 17.6, and 3.5 mg N kg-1 for HV, RC, ARG, RCG, corn, and the control,
 respectively. Mineralization in the HV treatment occurred from the third to the
 fifth day of the aerobic incubation and NH4+ continued to
 increase during the subsequent 2-d anaerobic period, reaching 58.4 mg NH4(+)-N
 kg-1. Nitrite accumulated during the anaerobic phase in all treatments, with 46
 and 49 mg N kg-1 for ARG and HV, respectively, during with the 2-d
 aerobic/2-d anaerobic incubation. With the 5-d aerobic/2-d anaerobic
 incubation, NO2(-) levels were lower in all but the ARG treatment.
 
 
 82                                                     NAL Call. No.: TD403.G7
 Designing a nitrate monitoring program in a heterogeneous, carbonate aquifer.
 Smith, R.T.; Ritzi, R.W. Jr
 Dublin, Ohio : Ground Water Pub. Co; 1993 Jul.
 Ground water v. 31 (4): p. 576-584; 1993 Jul.  Includes references.
 
 Language:  English
 
 Descriptors: Ohio; Aquifers; Carbonates; Hydraulic conductivity; Finite element
 analysis; Simulation models; Nitrates; Movement in soil; Zea mays; Glycine max;
 Rotations; Groundwater pollution
 
 
 83                                                   NAL Call. No.: TP368.F662
 Development of lupins as a new crop legume.
 Gladstones, J.S.
 North Sydney, Australia : Council of Australian Food Technology Associations;
 1990 Jun.
 Food Australia - official journal of CAFTA and AIFST v. 42 (6): p. 270-272;
 1990 Jun.
 
 Language:  English
 
 Descriptors: Australia; Lupins; New products; Product development; Legumes;
 History; Food research; Plant breeding; Food composition; Protein sources;
 Environmental factors; World markets; Rotations; Genetic improvement
 
 
 84                                              NAL Call. No.: S605.5.I45 1989
 Development of organic faming practices for sugarcane based farms.
 Mendosa, T.C.
 Witzenhausen? : Ekopan; 1990.
 Agricultural alternatives and nutritional self-sufficiency : for a sustainable
 agricultural system that respects man and his environment : proc of the IFOAM
 Seventh Int Scientific Conference, Ouagadougou, January 2-5, 1989. p. 189-202;
 1990.  Includes references.
 
 Language:  English
 
 Descriptors: Saccharum officinarum; Glycine max; Vigna radiata; Rhizobium;
 Organic farming; Farming systems; Intercropping; Green manures; Crop residues;
 Biodegradation; Row spacing; Row orientation; Planting; Harvesting; Crop yield;
 Soil degradation; Land productivity
 
 
 85                                                     NAL Call. No.: S671.A66
 Development of tillage system selection software for corn/soybean production.
 Meyer, C.R.; Parsons, S.D.; Griffith, D.R.; Mannering, J.V.; Steinhardt, G.C.
 St. Joseph, Mich. : American Society of Agricultural Engineers; 1991 May.
 Applied engineering in agriculture v. 7 (3): p. 367-373; 1991 May.  Includes
 references.
 
 Language:  English
 
 Descriptors: Zea mays; Glycine max; Production; Tillage; Computer software;
 Expert systems
 
 Abstract:  Development of a regionally-specific expert system to estimate
 corn/soybean production on an individual-field and whole-farm basis is
 described. Rules and equations to project yield as a function of tillage
 system, crop rotation, latitude, soil series, and soybean row spacing and
 maturity group were derived from interviews with three experts. The resulting
 knowledge was encoded into computer logic written entirely in C-language.
 Although very small, the program retains the functionality of expert systems
 developed in shells. On-line explanations are available to explain why each
 input is requested. Help screens offer expanded explanation of each question.
 Conclusions are displayed as they are reached. Management suggestions are
 offered where appropriate, including recommending a conservation tillage
 system, flagging highly erodible fields, indicating erosion control measures,
 suggesting that a field be tilled as two separate fields, and warning against
 farming steep slopes in row crops. The program goes beyond the features
 offered by some shells, permitting the user to back up in the program, to
 execute UNIX or DOS commands from within the program, and to store a partial
 run in a disk file to be resumed later. The program has been released as
 Public Domain software, with over 300 copies currently in use.
 
 
 86                                                     NAL Call. No.: 421 J822
 Discovery of multiyear diapause in Illinois and South Dakota northern corn
 rootworm (Coleoptera: Chrysomelidae) eggs and incidence of the prolonged
 diapause trait in Illinois.
 Levine, E.; Oloumi-Sadeghi, H.; Fisher, J.R.
 Lanham, Md. : Entomological Society of America; 1992 Feb.
 Journal of economic entomology v. 85 (1): p. 262-267; 1992 Feb.  Includes
 references.
 
 Language:  English
 
 Descriptors: Illinois; South Dakota; Zea mays; Diabrotica barberi; Diapause;
 Environmental temperature; Ova; Survival
 
 Abstract:  Northern corn rootworm, Diabrotica barberi Smith & Lawrence, eggs
 were obtained from female beetles collected in August 1985 from cornfields in
 Champaign, Ill., and Madison, S. Dak. Eggs were buried in soil or placed in
 environmental chambers that closely simulated natural soil temperature
 conditions and were observed for hatch during 4-5 yr. Egg diapause ranged from
 1 to 4 yr for both populations. Northern corn rootworm eggs were also obtained
 in August 1986 from female beetles collected from four Illinois cornfields that
 experienced greater rootworm damage than was expected for cornfields rotated
 annually with a soybean crop, and from females collected from the previously
 sampled Champaign field. The percentage of eggs that hatched after prolonged
 diapause (> 1 chill period) ranged from 13.9% for eggs from
 northwest Illinois to 51.3% for eggs from east central Illinois. When the
 percentage of northern corn rootworms with prolonged diapause in a given
 county was regressed on the percentage of rotational corn grown in that
 county, a significant positive correlation was obtained (r = 0.89, df = 3, P =
 0.04).
 
 
 87                                          NAL Call. No.: HD1401.S73 no.90-15
 Double-cropping soybeans into traditional crop rotations under government
 commodity program restrictions.
 Harper, Jayson K.
 Manhattan, Kansas : Dept. of Agricultural Economics, Kansas State University,;
 1990.
 9, [5] leaves ; 28 cm. (Staff paper / Department of Agricultural Economics,
 Kansas State University ; no. 90-15).  June 1990.  Includes bibliographical
 references (p. [1]).
 
 Language:  English
 
 
 88                                                    NAL Call. No.: 56.8 C162
 Early changes in water-stable aggregation induced by rotation and tillage in a
 soil under barley production.
 Angers, D.A.; Samson, N.; Legere, A.
 Ottawa : Agricultural Institute of Canada, 1957-; 1993 Feb.
 Canadian journal of soil science v. 73 (1): p. 51-59; 1993 Feb.  Includes
 references.
 
 Language:  English
 
 Descriptors: Aggregates; Stability; Formation; Particle size; Particle size
 distribution; Soil degradation; Soil management; Hordeum vulgare; Trifolium
 pratense; Rotations; Plowing; Chiselling; No-tillage; Conservation tillage;
 Soil water content; Soil organic matter; Chemical composition
 
 
 89                                                  NAL Call. No.: S592.7.A1S6
 Earthworm populations in dryland cropping soils under conservation-tillage in
 South Australia.
 Buckerfield, J.C.
 Exeter : Pergamon Press; 1992 Dec.
 Soil biology and biochemistry v. 24 (12): p. 1667-1672; 1992 Dec.  In the
 special issue ISEE 4. Proceedings of the "4th International Symposium on
 Earthworm Ecology," June 11-15, 1990, Avignon, France / edited by A.
 Kretzschmar.  Includes references.
 
 Language:  English
 
 Descriptors: South australia; Oligochaeta; Species; Aporrectodea caliginosa;
 Earthworms; Introduced species; Conservation tillage; Rotations; Population
 density; Biomass; Age structure; Population distribution; Soil depth; Soil
 water content; Seasonal variation; Precipitation; Dry farming
 
 Abstract:  The seasonal abundance of earthworms and their vertical
 distribution were studied in two adjacent fields, sown annually in an
 alternating cereal-legume rotation, with minimal cultivation and
 stubble-mulching. The introduced species Aporrectodea trapezoides, Microscolex
 dubius and M. phosphoreus were concentrated in the upper 10 cm of soil for
 90-150 days following the onset of autumn rains, but were not active in the top
 60 cm after the rainfall declined in spring and throughout the dry summer.
 Densities of up to 430 worms m-2 with a biomass of 111 g m-2 were recorded in
 the wetter months. M. dubius was the dominant species in both fields in both
 years. Differences in abundance, biomass and age-structure are discussed in
 relation to soil moisture, pH, carbonate, organic C and N, and to the phase of
 the crop rotation. The two fields have similar soils, similar cropping history
 and productivity, but one field had consistently higher earthworm numbers and
 biomass throughout 1988 and 1989. In each field the average size and total
 biomass were higher, growth rate higher and adults relatively more abundant
 under cereal than under the alternate legume phase.
 
 
 90                                                      NAL Call. No.: 450 C16
 Economic analysis of alternative cropping systems for a bean/wheat rotation on
 light-textured soils.
 Yiridoe, E.K.; Weersink, A.; Roy, R.C.; Swanton, C.J.
 Ottawa : Agricultural Institute of Canada; 1993 Apr.
 Canadian journal of plant science; Revue canadienne de phytotechnie v. 73 (2):
 p. 405-415; 1993 Apr.  Includes references.
 
 Language:  English
 
 Descriptors: Ontario; Triticum aestivum; Glycine max; Phaseolus vulgaris; No-
 tillage; Tillage; Rotations; Sandy loam soils; Crop yield; Returns; Production
 costs; Cover crops; Secale cereale; Zea mays
 
 
 91                                                   NAL Call. No.: S539.5.J68
 Economic analysis of including an annual forage in a corn-soybean farming
 system.
 Olson, K.D.; Martin, N.P.; Hicks, D.R.; Schmidt, M.A.
 Madison, Wis. : American Society of Agronomy; 1991 Oct.
 Journal of production agriculture v. 4 (4): p. 599-606; 1991 Oct.  Includes
 references.
 
 Language:  English
 
 Descriptors: Minnesota; Medicago sativa; Zea mays; Glycine max; Rotations; Farm
 enterprises; Microeconomic analysis; Decision making; Risks; Stochastic
 processes; Farm budgeting; Returns; Profits; Agricultural prices; Labor
 requirements; Crop quality; Crop yield; Machinery requirements; Farm
 management; Environmental impact; Case studies
 
 
 92                                                   NAL Call. No.: S605.5.A43
 An economic assessment of maintaining high phosphorus and potassium soil test
 levels.
 Chase, C.; Duffy, M.; Webb, J.; Voss, R.
 Greenbelt, Md. : Institute for Alternative Agriculture; 1991.
 American journal of alternative agriculture v. 6 (2): p. 83-86; 1991.
 Includes references.
 
 Language:  English
 
 Descriptors: Iowa; Zea mays; Glycine max; Rotations; Udolls; Phosphorus
 fertilizers; Potassium fertilizers; Application rates; Economic viability;
 Profitability; Production costs; Operating costs; Returns; Crop yield; Soil
 testing; Soil test values; Phosphorus; Potassium; Residual effects; Long term
 experiments; Seasonal variation; Fertilizer requirement determination;
 Sustainability
 
 Abstract:  Phosphorus (P) and potassium (K) fertilization costs, yields, and
 economic returns associated with various P and K fertilization levels were
 evaluated on corn and soybeans in rotation in northeastern Iowa from 1979 to
 1989. The treatments were 0, 20, and 40 lb P/acre and 0, 60, and 120 lb
 K/acre, in all nine combinations, plus the high rate (40 + 120) applied on
 alternate years. (The latter treatment applied, respectively, in odd or even
 years was averaged into one treatment.) The initial soil test levels averaged
 57 pounds of P and 355 pounds of K The P-K treatments did not significantly
 explain the variation in corn or soybean yields. Net returns were found
 directly related to the cost of the treatment, so that the control treatment (0
 + 0) achieved the highest returns. The cost of using the 20 + 60 treatment to
 maintain soil test levels in the high to very high range was $24/acre per year.
 Annual application of 40 + 120 cost $45/acre. A sufficiency approach to
 applying P and K could drastically reduce fertilizer costs for high-testing
 soils. Further research is needed to determine if recommendations from this
 approach can be lowered in some cases. Extension workers must continue to
 develop ways to aid farmers in realizing the usefulness of soil testing.
 Farmers must carefully evaluate their fertilization needs in conjunction with
 soil test results. Together, a more sustainable approach to P and K
 fertilization for corn and soybeans may be attained.
 
 
 93                                                   NAL Call. No.: S605.5.A43
 An economic comparison of conventional and reduced-chemical farming systems in
 Iowa.
 Chase, C.; Duffy, M.
 Greenbelt, Md. : Institute for Alternative Agriculture; 1991.
 American journal of alternative agriculture v. 6 (4): p. 160-173; 1991.
 Includes references.
 
 Language:  English
 
 Descriptors: Iowa; Zea mays; Glycine max; Avena sativa; Alfalfa hay; Meadows;
 Economic analysis; Cropping systems; Farming systems; Agricultural chemicals;
 Comparisons; Alternative farming; Yields; Returns; Land; Labor requirements;
 Production costs; Profitability; Labor costs; Farm management
 
 Abstract:  Labor requirements, production costs, yields, and economic returns
 were evaluated for conventional and reduced-chemical cropping systems in
 northeast Iowa from 1978 to 1989. Continuous corn (C-C) and corn-soybean
 (C-Sb) rotations represented the conventional system; a corn-oat-meadow
 (C-O-M) rotation represented the reduced-chemical system. The C-C and C-Sb
 rotations used both commercial pesticides and fertilizers. The C-O-M rotation
 used manure for fertilization and applied pesticides only in emergencies.
 Operations for all systems were implemented by one farm manager. The C-Sb
 rotation had the highest corn yield over the 12-year period, and the C-O-M
 rotation the lowest. The corn within the C-O-M rotation, however, produced the
 second highest average return to land labor, and management. With costs of
 production substantially lower than the conventional systems, the C-O-M corn
 crop had competitive returns despite lower-yield. The C-Sb average return to
 land, labor, and management was significantly higher than for the other
 systems. Hourly labor charges of $4, $10, $20, and $50 had little effect on the
 rankings of economic returns. Because of unusually high alfalfa reseeding costs
 and low average oat yields, returns to the C-O-M rotation were
 significantly lower than C-Sb but comparable to C-C. With better alfalfa
 establishment and higher average oat yields, the reduced-chemical system might
 have been competitive with the C-Sb conventional system.
 
 
 94                                                     NAL Call. No.: 79.8 W41
 The economics of alternative tillage systems, crop rotations, and herbicide use
 on three representative East-Central Corn Belt farms.
 Martin, M.A.; Schreiber, M.M.; Riepe, J.R.; Bahr, J.R.
 Champaign, Ill. : Weed Science Society of America; 1991 Apr.
 Weed science v. 39 (2): p. 299-307; 1991 Apr.  Includes references.
 
 Language:  English
 
 Descriptors: Indiana; Triticum aestivum; Zea mays; Glycine max; Cost benefit
 analysis; Conservation tillage; Sustainability; Integrated pest management;
 Alternative farming; Farm income; Farm inputs; Herbicides; Weed control;
 Rotations; Farm size; No-tillage; Farm results; Crop yield; Continuous
 cropping; Chiselling; Mathematical models; Linear programming
 
 Abstract:  A linear programming model was used to determine which crop
 rotations and weed management systems result in the highest net farm income for
 each of three farm sizes (120, 240, and 480 hectares) under alternative tillage
 systems. Test plot data for the years 1981 through 1988 from the
 Purdue University Agronomy Farm, which has highly productive, well-drained
 soils, were analyzed. Net incomes for no-till tillage systems on all farms in
 the model were consistently and significantly lower than incomes for moldboard
 and chisel plow tillage systems due to slightly lower yields and substantially
 higher herbicide costs. Generally, net farm incomes were slightly higher with a
 moldboard plow versus chisel plow tillage system. Also, as farm size
 increased, per hectare net incomes increased. About 80% of the time under
 moldboard or chisel plow tillage systems, the model chose as optimal the
 lowest of three herbicide application rates. A corn/soybean rotation was
 chosen as optimal on 56% of the farm area analyzed, versus 25% for continuous
 corn and 13% for a corn/soybean/wheat rotation.
 
 
 95                                                    NAL Call. No.: SB610.W39
 Effect of 2,4-D and dicamba residues on following crops in conservation
 tillage systems.
 Moyer, J.R.; Bergen, P.; Schaalje, G.B.
 Champaign, Ill. : The Society; 1992 Jan.
 Weed technology : a journal of the Weed Science Society of America v. 6 (1): p.
 149-155; 1992 Jan.  Includes references.
 
 Language:  English
 
 Descriptors: Hordeum vulgare; Triticum aestivum; Lens culinaris; Pisum sativum;
 Brassica napus; Rotations; Medicago sativa; Conservation tillage; Weed control;
 Chemical control; Herbicide residues; 2,4-d; Dicamba; Glyphosate; Residual
 effects; Application date; Phytotoxicity; Crop damage; Spring; Sowing date;
 Crop yield
 
 
 96                                                    NAL Call. No.: SB610.W39
 Effect of AC 222,293 soil residues on rotational crops.
 Fellows, G.M.; Fay, P.K.; Carlson, G.R.; Stewart, V.R.
 Champaign, Ill. : The Society; 1990 Jan.
 Weed technology : a journal of the Weed Science Society of America v. 4 (1): p.
 48-51; 1990 Jan.  Includes references.
 
 Language:  English
 
 Descriptors: Montana; Triticum aestivum; Hordeum vulgare; Helianthus annuus;
 Rotations; Lens culinaris; Brassica napus; Beta vulgaris; Avena fatua; Solanum
 tuberosum; Herbicide residues; Residual effects; Pesticide persistence;
 Herbicide rates; Phytotoxicity
 
 
 97                                                    NAL Call. No.: SB610.W39
 Effect of atrizine and tillage on alfalfa (Medicago sativa) establishment in
 corn (Zea mays)-alfalfa rotation.
 Kells, J.J.; Leep, R.H.; Tesar, M.B.; Leavitt, R.A.; Cudnohufsky, J.
 Champaign, Ill. : The Society; 1990 Apr.
 Weed technology : a journal of the Weed Science Society of America v. 4 (2): p.
 360-365. ill; 1990 Apr.  Includes references.
 
 Language:  English
 
 Descriptors: Michigan; Zea mays; Medicago sativa; Rotations; Sequential
 cropping; Seedlings; Phytotoxicity; Atrazine; Abiotic injuries; No-tillage;
 Plowing; Persistence; Herbicide residues; Spatial distribution; Crop
 establishment
 
 
 98                                                      NAL Call. No.: 26 T754
 Effect of continued cropping on a heavy clay soil on the coast of Guyana with
 and without tillage.
 Simpson, L.A.; Gumbs, F.A.
 London : Butterworth-Heinemann; 1992 Apr.
 Tropical agriculture v. 69 (2): p. 111-118; 1992 Apr.  Includes references.
 
 Language:  English
 
 Descriptors: Guyana; Vigna unguiculata; Zea mays; Rotations; No-tillage; Rain;
 Soil temperature; Soil water; Tillage; Crop yield; Clay soils
 
 
 99                                                     NAL Call. No.: 1.9 P69P
 The effect of cover crops and fertilization with ammonium nitrate on corky root
 of lettuce.
 Van Bruggen, A.H.C.; Brown, P.R.; Shennan, C.; Greathead, A.S.
 St. Paul, Minn. : American Phytopathological Society; 1990 Aug.
 Plant disease v. 74 (8): p. 584-588; 1990 Aug.  Includes references.
 
 Language:  English
 
 Descriptors: California; Lactuca sativa; Cover crops; Ammonium nitrate;
 Corking; Roots; Secale cereale; Winter; Crop yield; Soil water; Soil structure;
 Inoculum; Seasonal variation; Vicia faba; Dry matter; Bacterial diseases; Gram
 negative bacteria; Disease control; Cultural control; Nitrogen content
 
 
 100                                                   NAL Call. No.: 56.8 C162
 Effect of crop rotations and cultural practices on soil organic matter,
 microbial biomass and respiration in a thin Black Chernozem.
 Campbell, C.A.; Biederbeck, V.O.; Zentner, R.P.; Lafond, G.P.
 Ottawa : Agricultural Institute of Canada; 1991 Aug.
 Canadian journal of soil science v. 71 (3): p. 363-376; 1991 Aug.  Includes
 references.
 
 Language:  English
 
 Descriptors: Saskatchewan; Triticum aestivum; Melilotus officinalis; Bromus
 inermis; Medicago sativa; Chernozems; Soil organic matter; Crop management;
 Fertilizers; Rotation; Continuous cropping; Fallow; Biomass; Respiration;
 Mineralization; Carbon; Nitrogen; Carbon dioxide; Carbon-nitrogen ratio; Plant
 analysis; Crop residues; Nutrient content; Green manures; Straw disposal; Crop
 yield; Grain; Soil depth; A horizons; Long term experiments
 
 
 101                                                   NAL Call. No.: 56.8 C162
 Effect of crop rotations and fertilization on soil organic matter and some
 biochemical properties of a thick Black Chernozem.
 Campbell, C.A.; Canada; Bowren, K.E.; Schnitzer, M.; Zentner, R.P.; Townley-
 Smith, L.
 Ottawa : Agricultural Institute of Canada; 1991 Aug.
 Canadian journal of soil science v. 71 (3): p. 377-387; 1991 Aug.  Includes
 references.
 
 Language:  English
 
 Descriptors: Saskatchewan; Triticum aestivum; Melilotus officinalis; Bromus
 inermis; Medicago sativa; Chernozems; Soil organic matter; Crop management;
 Fertilizers; Continuous cropping; Rotations; Fallow; Carbon; Nitrogen;
 Mineralization; Amino acids; Spatial distribution; Amino sugars; Carbon-
 nitrogen ratio; A horizons; Surface layers; Green manures; Crop residues;
 Nutrient content; Soil depth; Biological activity in soil; Long term
 experiments
 
 
 102                                                   NAL Call. No.: 56.8 C162
 Effect of crop rotations on microbial biomass, specific respiratory activity
 and mineralizable nitrogen in a Black Chernozemic soil.
 Campbell, C.A.; Moulin, A.P.; Bowren, K.E.; Janzen, H.H.; Townley-Smith, L.;
 Biederbeck, V.O.
 Ottawa : Agricultural Institute of Canada, 1957-; 1992 Nov.
 Canadian journal of soil science v. 72 (4): p. 417-427; 1992 Nov.  Includes
 references.
 
 Language:  English
 
 Descriptors: Saskatchewan; Cabt; Triticum aestivum; Rotations; Melilotus
 officinalis; Green manures; Soil flora; Biomass; Respiration; Biological
 activity in soil; Nitrogen; Mineralization; Chernozemic soils; Fertilizers
 
 
 103                                                   NAL Call. No.: 56.8 C162
 Effect of cropping practices on the initial potential rate of N mineralization
 in a thin Black Chernozem.
 Campbell, C.A.; LaFond, G.P.; Leyshon, A.J.; Zentner, R.P.; Janzen, H.H.
 Ottawa : Agricultural Institute of Canada; 1991 Feb.
 Canadian journal of soil science v. 71 (1): p. 43-53; 1991 Feb.  Includes
 references.
 
 Language:  English
 
 Descriptors: Saskatchewan; Triticum aestivum; Bromus inermis; Medicago sativa;
 Chernozems; Agricultural soils; Nitrogen; Mineralization; Soil organic matter;
 Rotations; Continuous cropping; Green manures; Fertilizers; Soil fertility;
 Sustainability
 
 
 104                                                 NAL Call. No.: QL391.N4J62
 Effect of cropping regime on populations of Belonolaimus sp. and Pratylenchus
 scribneri in sandy soil.
 Todd, T.C.
 Lake Alfred, Fla. : Society of Nematologists; 1991 Oct.
 Journal of nematology v. 23 (4,suppl.): p. 646-651; 1991 Oct.  Includes
 references.
 
 Language:  English
 
 Descriptors: Kansas; Glycine max; Medicago sativa; Sorghum bicolor; Triticum
 aestivum; Zea mays; Belonolaimus; Pratylenchus scribneri; Rotations; Population
 density
 
 Abstract:  The host efficiencies of corn, sorghum, soybean, and wheat were
 compared for a Kansas population of Belonolaimus sp. under greenhouse
 conditions. In a related field study conducted in 1989 and 1990, the responses
 of Belonolaimus sp. and Pratylenchus scribneri populations to eight cropping
 regimes were monitored at depths of 0-30 and 31-60 cm in sandy soil. With the
 exception of alfalfa, all crop species examined supported substantial
 increases in populations of both nematodes. Largest nematode population
 increases in the field occurred in corn plots, whereas alfalfa did not allow
 reproduction by either species during the 2 years of observation. Soil
 populations of both nematodes remained at detectable levels after 2 years of
 fallow. The distribution of numbers of Belonolaimus sp. between soil depths
 varied with sampling date, whereas populations of P. scribneri were
 consistently concentrated in the top 30 cm of soil.
 
 
 105                                                    NAL Call. No.: 56.8 SO3
 Effect of cropping systems on adsorption of metals by soils. I. Single-metal
 adsorption.
 Basta, N.T.; Tabatabai, M.A.
 Baltimore, Md. : Williams & Wilkins; 1992 Feb.
 Soil science v. 153 (2): p. 108-114; 1992 Feb.  Includes references.
 
 Language:  English
 
 Descriptors: Iowa; Zea mays; Glycine max; Avena sativa; Medicago sativa;
 Trifolium pratense; Mollisols; Clay loam soils; Silt loam soils; Rotations;
 Continuous cropping; Heavy metals; Adsorption; Lead; Copper; Cadmium; Zinc;
 Nickel; Ammonium fertilizers; Urea fertilizers; Soil treatment; Ammonium; Soil
 ph; Soil organic matter; Carbon; Base saturation; Cation exchange capacity;
 Particle size distribution; Sorption isotherms; Crop management; Long term
 experiments
 
 
 106                                                  NAL Call. No.: QH84.8.B46
 Effect of green manuring, blue-green algae and neem-cake-coated urea on
 wetland rice (Oryza sativa L.).
 Singh, S.; Prasad, R.; Singh, B.V.; Goyal, S.K.; Sharma, S.N.
 Berlin : Springer International; 1990.
 Biology and fertility of soils v. 9 (3): p. 235-238; 1990.  Includes
 references.
 
 Language:  English
 
 Descriptors: India; Oryza sativa; Cyanobacteria; Green manures; Neem cake
 coated urea; Sesbania aculeata; Urea fertilizers; Yield components; Yield
 increases
 
 
 107                                              NAL Call. No.: S592.17.A73A74
 Effect of green manuring with Sesbania aculeata on physical properties of soil
 and on growth of wheat in rice-wheat and maize-wheat cropping systems in a
 semiarid region of India.
 Boparai, B.S.; Yadvinder-Singh; Sharma, B.D.
 Washington, DC : Taylor & Francis; 1992 Apr.
 Arid soil research and rehabilitation v. 6 (2): p. 135-143; 1992 Apr.
 Includes references.
 
 Language:  English
 
 Descriptors: Indian punjab; Sesbania aculeata; Green manures; Incorporation;
 Oryza sativa; Zea mays; Triticum aestivum; Winter wheat; Rotations; Residual
 effects; Roots; Growth; Density; Crop yield; Grain; Aggregates; Stability; Soil
 density; Bulk density; Infiltration; Soil water content; Soil water retention;
 Hydraulic conductivity; Soil organic matter; Carbon; Semiarid climate;
 Irrigated conditions; Flooding; Puddling; Sandy soils
 
 
 108                                                   NAL Call. No.: S451.M9M9
 Effect of harvest management and nurse crop on production of five small-seeded
 legumes.
 Welty, L.E.; Westcott, M.P.; Prestbye, L.S.; Knox, M.L.
 Bozeman, Mont. : The Station; 1991.
 Montana agresearch - Montana Agricultural Experiment Station, Montana
 University v. 8 (1): p. 11-17; 1991.  Includes references.
 
 Language:  English
 
 Descriptors: Montana; Green manures; Trifolium alexandrinum; Medicago sativa;
 Trifolium resupinatum; Companion crops; Avena sativa; Harvesting; Management
 
 
 109                                                   NAL Call. No.: S596.7.D4
 Effect of incorporated green manure crops on subsequent oat production in an
 acid, infertile silt loam.
 Warman, P.R.
 Dordrecht : Kluwer Academic Publishers; 1991.
 Developments in plant and soil sciences v. 45: p. 431-435; 1991.  In the
 series analytic: Plant-Soil Interactions at Low pH / edited by R.J. Wright,
 V.C. Baligar and R.P. Murrmann. Proceedings of the Second International
 Symposium, June 24-29, 1990, Beckley, West Virginia.  Includes references.
 
 Language:  English
 
 Descriptors: Acid soils; Silt loam soils; Green manures; Oryza sativa; Crop
 yield
 
 Abstract:  A field-size experiment was initiated in 1982 on an acid, low
 fertility Springhill silt loam to determine the effect of five unfertilized
 green manure crops (alsike clover, sweet clover, single- and double-cut red
 clover, and buckwheat) on subsequent oat production and soil fertility. The
 field was limed in 1982 and green manures were seeded (without fertilizer) in
 spring, 1983 in 1400 m2 strips randomly assigned within three treatment
 blocks. Plant tissue samples were taken from different locations in each plot
 in the fall of 1983 and all crops were incorporated. In 1984 the field was
 separated into an upper and lower section and each section received three rates
 of NPK fertilizer (0; 30-36-36; 60-72-72 kg per ha-1) spread across the
 previous strips. Gary oats were seeded and at harvest were divided into grain
 and straw. The results indicated significant effects of field sample location,
 green manure type and fertilizer level on oat yields. Buckwheat significantly
 reduced oat production compared to the four clovers, while the highest
 fertilizer rate improved oat yields compared with the other levels of
 fertilizers. Elemental analysis of the green manure crops and soil fertility
 was compared with data of the same crops grown in more fertile, neutral soils.
 
 
 110                                                 NAL Call. No.: QK898.N6N52
 Effect of incorporating plant materials on corn growth.
 Kaufusi, P.; Asghar, M.
 Bangkok, Thailand : Thailand Institute of Scientific and Technological
 Research; 1990 Aug.
 Nitrogen fixing tree research reports v. 8: p. 81-82; 1990 Aug.  Includes
 references.
 
 Language:  English
 
 Descriptors: Zea mays; Leguminosae; Green manures; Soil fertility; Growth;
 Indicator plants; Plant nutrition
 
 
 111                                                  NAL Call. No.: S539.5.A77
 The effect of pea cultivation on succeeding winter cereals and winter oilseed
 rape nitrogen nutrition.
 Jensen, E.S.; Haahr, V.
 New York, N.Y. : Springer; 1990.
 Applied agricultural research v. 5 (2): p. 102-107; 1990.  Includes
 references.
 
 Language:  English
 
 Descriptors: Pisum sativum; Avena sativa; Hordeum vulgare; Triticum aestivum;
 Nitrogen uptake; Nutrient contents of plants; Straw; Rotations; Dry matter
 accumulation; Grain; Crop yield
 
 Abstract:  A short-term crop rotation experiment was carried out in duplicate
 three-year periods to evaluate the residual N effect of cultivating pea (Pisum
 sativum L.) for harvest at the dry seed stage in comparison to oats (Avena
 sativa L.). Winter barley (Hordeum vulgare L.), winter wheat (Triticum
 aestivum L.), and winter oilseed rape (Brassica napus oleifera L.) followed pea
 or oats and the third-phase crops were winter barley and winter oilseed rape.
 Two weeks after the harvest of pea and oats, the soil profile (to 1 m depth)
 contained on average 30 kg N/ha (26.7 lb N/A) more after pea than after oats.
 The N accumulation in winter barley, winter wheat, and winter oilseed rape
 until early December was on average 15 kg N/ha higher after pea than after
 oats. Barley and oilseed rape were more efficient than wheat in
 accumulating N during the autumn. The residual N effect of pea as measured by
 grain yields of winter cereals not supplied with N fertilizer was equivalent to
 spring application of 20 to 30 kg N/ha to crops following oats. In winter
 cereals given 90 or 120 kg N/ha, only a small residual N effect of pea was
 observed. With winter cereals, the rotation effect of pea is probably more
 important than the residual N effect. In winter oilseed rape, the residual N
 effect was equivalent to 30 to 60 kg N/ha applied to crops following oats, at
 all levels of N fertilization. Removal of the above-ground pea residues, which
 contained less than 1% N, had no influence on the residual N effect. The yield
 of crops grown in the second year after pea and oats was not significantly
 influenced by the first-phase crop.
 
 
 112                                                    NAL Call. No.: 382 So12
 Effect of residual fertility and direct fertilisation on kernel, protein and
 oil yield of peanut (Arachis hypogaea L) grown in rice fallows.
 Thimmegowda, S.
 Essex : Elsevier Applied Science; 1993.
 Journal of the science of food and agriculture v. 61 (4): p. 385-387; 1993.
 Includes references.
 
 Language:  English
 
 Descriptors: Arachis hypogaea; Cultivation; Fallow; Rotations; Oryza sativa;
 Green manures; Residual effects; Soil fertility; Npk fertilizers; Crop yield;
 Kernels; Protein; Peanut oil
 
 Abstract:  Kernel (2814-3467 kg ha-1), protein (555-759 kg ha-1) and oil
 (124-1556 kg ha-1) yields of peanut (Arachis hypogaea L) varied significantly
 due to the residual effect of organic manures and inorganic fertilisers
 together. It was also observed that direct application of recommended
 fertilisers (25 N, 72 P2O5 and 37.5 K2O kg ha-1) gave the highest kernel (3669
 kg ha-1), protein (786 kg ha-1) and oil (1606 kg ha-1) yields. The reduction in
 kernel, protein and oil yield from the recommended level of fertilisers to half
 the recommended level of fertilisers was about 16, 15 and 12% while it was
 about 25, 33 and 27% with no fertiliser. Thus, the results revealed that the
 nutrients applied partly through organic manures and inorganic fertilisers to
 Kharif rice exhibits significant residual effects on the succeeding upland crop
 and hence the fertilisation must be considered not only for individual crops
 but also for the cropping system as a whole.
 
 
 113                                                 NAL Call. No.: HD1773.A3N6
 Effect of risk preferences on incorporation of double-crop soybeans into
 traditional rotations.
 Harper, J.K.; Williams, J.R.; Burton, R.O. Jr; Kelley, K.W.
 East Lansing, Mich. : Michigan State University; 1991 Jul.
 Review of agricultural economics v. 13 (2): p. 185-200; 1991 Jul.  Includes
 references.
 
 Language:  English
 
 Descriptors: Kansas; Soybeans; Wheat; Sorghum; Double cropping; Farm
 management; Risk; Decision making; Innovation adoption; Returns; Market prices;
 Crop yield; Production costs; Federal programs; Interest rates; Target prices;
 Mathematical models
 
 Abstract:  Six enterprise combinations, four including a double-crop sequence
 of wheat followed immediately after harvest by soybeans, were evaluated for
 southeastern Kansas given the requirements for participation in the government
 commodity program. Stochastic dominance analysis was used to select the
 preferred combination under six different classes of risk preferences. A
 two-year sequence of wheat double-cropped with soybeans followed by
 full-season soybeans was the preferred combination for all classes of risk
 preferences analyzed. Sensitivity analysis indicated that if labor, machinery,
 or field time constraints limit the number of acres of double-cropped soybeans
 and/or if farm yields are sufficiently less than those included in the data
 set, results would either favor rotations that do not double-crop or those that
 double-crop less than the maximum number of acres each year.
 
 
 114                                                    NAL Call. No.: 23 AU783
 Effect of rotation and inoculation with Bradyrhizobium on nitrogen fixation and
 yield of peanut (Arachis hypogaea L., cv. Virginia Bunch).
 Peoples, M.B.; Bell, M.J.; Bushby, H.V.A.
 Melbourne : Commonwealth Scientific and Industrial Research Organization; 1992.
 Australian journal of agricultural research v. 43 (3): p. 595-607; 1992.
 Includes references.
 
 Language:  English
 
 Descriptors: Queensland; Arachis hypogaea; Rotations; Sequential cropping; Soil
 inoculation; Bradyrhizobium; Nitrogen fixation; Crop yield
 
 
 115                                                   NAL Call. No.: SB610.W39
 Effect of rye (Secale cereale) mulch on weed control and soil moisture in
 soybean (Glycine max).
 Liebl, R.; Simmons, F.W.; Wax, L.M.; Stoller, E.W.
 Champaign, Ill. : The Weed Science Society of America; 1992 Oct.
 Weed technology : a journal of the Weed Science Society of America v. 6 (4): p.
 838-846; 1992 Oct.  Includes references.
 
 Language:  English
 
 Descriptors: Illinois; Cabt; Glycine max; Conservation tillage; No-tillage;
 Mulching; Secale cereale; Cover crops; Zea mays; Crop residues; Weed control;
 Chenopodium album; Setaria faberi; Amaranthus hybridus; Abutilon theophrasti;
 Soil water content; Crop yield; Herbicides; Application date; Planting date
 
 
 116                                                  NAL Call. No.: 442.8 AN72
 The effect of stem nematode on establishment and early yields of white clover.
 Cook, R.; Evans, D.R.; Williams, T.A.; Mizen, K.A.
 Warwick : Association of Applied Biologists; 1992 Feb.
 Annals of applied biology v. 120 (1): p. 83-94; 1992 Feb.  Includes
 references.
 
 Language:  English
 
 Descriptors: Trifolium repens; Cultivars; Lolium perenne; Ditylenchus dipsaci;
 Infestation; Aldicarb; Rotations; Varietal resistance; Crop establishment; Crop
 yield
 
 
 117                                                     NAL Call. No.: 450 C16
 Effect of tillage implement and date of sweetclover incorporation on available
 soil N and succeeding spring wheat yields.
 Foster, R.K.
 Ottawa : Agricultural Institute of Canada; 1990 Jan.
 Canadian journal of plant science; Revue canadienne de phytotechnie v. 70 (1):
 p. 269-277; 1990 Jan.  Includes references.
 
 Language:  English
 
 Descriptors: Melilotus officinalis; Tillage; Incorporation; Green manures; Soil
 chemistry; Nitrogen; Triticum aestivum; Spring wheat; Crop yield; Timing
 
 
 118                                                     NAL Call. No.: 450 C16
 Effect of tillage on nitrogen response in corn (Zea mays L.) after established
 alfalfa (Medicago sativa L.).
 Aflkpui, G.K.S.; Vyn, T.J.; Hall, M.R.; Anderson, G.W.; Swanton, C.J.
 Ottawa : Agricultural Institute of Canada; 1993 Jan.
 Canadian journal of plant science; Revue canadienne de phytotechnie v. 73 (1):
 p. 73-81; 1993 Jan.  Includes references.
 
 Language:  English
 
 Descriptors: Ontario; Zea mays; Medicago sativa; Nitrogen fertilizers;
 Rotations; Tillage; Crop yield; Harvest index
 
 
 119                                                  NAL Call. No.: S539.5.A77
 Effect of tillage on soil water and alfalfa establishment in corn stubble.
 Stout, W.L.; Byers, R.A.; Bahler, C.C.; Hoffman, L.D.
 New York, N.Y. : Springer; 1990.
 Applied agricultural research v. 5 (3): p. 176-180; 1990.  Includes
 references.
 
 Language:  English
 
 Descriptors: Pennsylvania; Medicago sativa; Tillage; Soil water; Establishment;
 Maize stover; Soil water content; Secale cereale; No-tillage; Sowing date; Crop
 yield; Cover crops; Sowing depth
 
 Abstract:  The effect of soil water on alfalfa (Medicago sativa L.) seedling
 growth during no-till establishment into corn stubble has not been documented.
 Our objective was to determine the effects of differences in soil water levels
 resulting from different tillage methods and seeding dates on alfalfa
 emergence and seedling growth. The experiment was located at the Rock Spring
 Agricultural Research Center in Centre County, PA (40 degrees 42'N Lat., 77
 degrees 57'W Long., elev. 365 m (1200 ft)), on a Hublersburg silt loam soil
 (clayey, mixed, mesic typic Hapludult) in 1986 and 1987 and a Hagerstown silt
 loam soil (fine, mixed, mesic Typic Hapludalf) in 1988. Alfalfa (cv. 'WL316')
 was drilled no-till into stubbles from corn harvested for grain (NT-G), silage
 (NT-S), or silage plus a rye (Secale cereale L. cv. common) cover crop
 (NT-SR), and seeded into a conventionally prepared seedbed resulting from corn
 harvested for grain (CT). Seeding dates were early April (EA), late April (LA),
 and mid-May (MM). Soil water content was not adversely affected by the
 inclusion of the rye cover crop in the NT-SR treatment. Good stands of over 70%
 seedling frequency were obtained with all treatments, but the NT-S
 treatment had significantly higher seedling yields, yields at one-tenth bloom,
 and total seedling year yields than the others. Seedling yields were
 significantly lower in the NT-SR treatment, however rye silage yields made this
 treatment one of the most productive in the seedling year. In addition the rye
 cover crop of the NT-SR treatment provides a conservation cover during the
 winter and a means of capturing nitrate left over from the corn crop or
 mineralized during the early spring. In the first production year, there was no
 significant effect of tillage or seeding date on first harvest yields.
 
 
 120                                                    NAL Call. No.: 56.8 AU7
 Effects of 8-year rotations of grain sorghum with lucerne, annual legume, wheat
 and long fallow on nitrogen and organic carbon in two contrasting soils.
 Holford, I.C.R.
 East Melbourne : Commonwealth Scientific and Industrial Research Organization;
 1990.
 Australian journal of soil research v. 28 (2): p. 277-291; 1990.  Includes
 references.
 
 Language:  English
 
 Descriptors: New South Wales; Soil fertility; Red clay soils; Black earths;
 Sorghum bicolor; Medicago sativa; Triticum aestivum; Annual field crops;
 Rotations; Continuous cropping; Fallow systems; Nitrate nitrogen; Nitrogen;
 Carbon; Organic matter in soil; Soil moisture; Bulk density; Nitrogen uptake;
 Grain; Crop yield; Seasonal fluctuations
 
 
 121                                                    NAL Call. No.: 470 C16C
 Effects of crop sequence and rainfall on population dynamics of Fusarium
 solani f.sp. phaseoli in soil.
 Hall, R.; Phillips, L.G.
 Ottawa, Ont. : National Research Council of Canada; 1992 Oct.
 Canadian journal of botany; Journal canadien de botanique v. 70 (10): p.
 2005-2008; 1992 Oct.  Includes references.
 
 Language:  English
 
 Descriptors: Ontario; Fusarium solani f.sp. phaseoli; Population dynamics;
 Population density; Agricultural soils; Rain; Rotations; Zea mays; Glycine max;
 Phaseolus vulgaris
 
 
 122                                                  NAL Call. No.: SB327.A1B5
 Effects of crop sequence and weather on soil populations of Fusarium solani f.
 sp. phaseoli.
 Hall, R.
 Fort Collins, Colo : Howard F. Schwartz, Colorado State University; 1992.
 Annual report of the Bean Improvement Cooperative v. 35: p. 115-116; 1992.
 
 Language:  English
 
 Descriptors: Ontario; Phaseolus vulgaris; Fusarium solani f.sp. phaseoli;
 Infectivity; Inoculum density; Rotations; Climatic factors
 
 
 123                                                    NAL Call. No.: 1.9 P69P
 Effects of cropping systems on population density of Heterodera glycines and
 soybean yield.
 Koenning, S.R.; Schmitt, D.P.; Barker, K.R.
 St. Paul, Minn., American Phytopathological Society; 1993 Aug.
 Plant Disease v. 77 (8): p. 780-786; 1993 Aug.  Includes references.
 
 Language:  English
 
 Descriptors: Glycine max; Cultivars; Maturity groups; Heterodera glycines;
 Populations; Population density; Crop yield; Rotations; Planting date
 
 
 124                                                    NAL Call. No.: 23 AU783
 The effects of fumigation, rotation with lupins, and nitrogen application on
 plant growth and common root rot of wheat at Geraldton, Western Australia.
 Wilson, J.M.; Hamblin, J.
 Melbourne : Commonwealth Scientific and Industrial Research Organization; 1990.
 Australian journal of agricultural research v. 41 (4): p. 619-631; 1990.
 Includes references.
 
 Language:  English
 
 Descriptors: Western australia; Triticum; Root rots; Cochliobolus sativus;
 Fungus control; Lupinus; Nitrogen fertilizers; Rotations; Soil fumigation
 
 
 125                                                  NAL Call. No.: S605.5.A43
 Effects of intensity of agronomic practices on a soil ecosystem.
 Weil, R.R.; Lowell, K.A.; Shade, H.M.
 Greenbelt, MD : Henry A. Wallace Institute for Alternative Agriculture; 1993.
 American journal of alternative agriculture v. 8 (1): p. 5-14; 1993.  Includes
 references.
 
 Language:  English
 
 Descriptors: Soil biology; Ecosystems; Soil organic matter; Cropping systems;
 Sustainability; Organic farming; Tillage; Nitrogen fertilizers; Cycling;
 Earthworms
 
 Abstract:  Monitoring soil biological activity may provide useful information
 in assessing the sustainability of agricultural systems. From 1985 to 1992, we
 compared five cropping systems in southern Maryland. Four of the systems
 involved the production of wheat, soybean, or corn, but differed in intensity
 of tillage, herbicide use, crop biomass removal, and N fertilizer application.
 The fifth system was continuous grass. The objective was to assess how these
 cropping systems affected selected indicators of soil biological activity and
 nutrient cycling. From Fall, 1990 through Fall 1991 the upper layers (0-5 or
 0-15 cm) of soil were studied to assess C and N contents, selected physical
 properties, extractable organic C, microbial respiration, decomposition of
 plant tissue, N mineralization, and earthworm (Lumbricidae) populations. On a
 dry weight basis total and labile C were significantly higher under grass and
 lower under conventionally tilled (CT) continuous corn than in the other three
 systems. In fall, there were significantly fewer earthworms (10.4 m-2) under
 the reduced input rotation than in any other system, and fewer under CT
 continuous corn than in the organic (corn-wheat-green manure) rotation or
 grass. In general, the rates of CO2 evolution were 30 to 35% lower in fall
 (11.5 to 22.5 kg C ha-1 d-1) than in spring (17.3 to 33.7 kg C ha-1 d-1).
 During both seasons grass had approximately twice as much soil metabolic
 activity as CT continuous corn. The absence of tillage clearly was important in
 increasing N mineralization capacity, since the two untilled systems had
 comparable rates of N release that were significantly greater than those for
 the other systems. Among the tilled systems, mineral N after laboratory
 incubation decreased with increasing frequency and intensity of tillage in the
 order: reduced input > organic > CT continuous corn. It was evident from a
 combination of measures that soil biological activity was enhanced in the
 systems that minimized tillage. The results underscored the value of grass for
 soil improvement.
 
 
 126                                                      NAL Call. No.: S79.E3
 The effects of lay-by herbicides on wheat, vetch, and winter weeds as cover
 crops for cotton.
 Hurst, H.R.
 Mississippi State, Miss. : The Station; 1992 Jun.
 Bulletin - Mississippi Agricultural and Forestry Experiment Station (982): 6
 p.; 1992 Jun.  Includes references.
 
 Language:  English
 
 Descriptors: Mississippi; Gossypium hirsutum; Triticum aestivum; Vicia sativa;
 Weeds; Herbicide residues; Cover crops; Adverse effects; Plant density
 
 
 127                                                  NAL Call. No.: S542.A8A34
 Effects of legumes in a cropping rotation on an infertile soil in Machakos
 District, Kenya.
 Simpson, J.R.; Karanja, D.R.; Ikombo, B.M.; Keating, B.A.
 Canberra : Australian Centre for International Agricultural Research; 1992.
 ACIAR proceedings (41): p. 44-49; 1992.  In the series analytic: A search for
 strategies for sustainable dryland cropping in semi-arid eastern Kenya /
 edited by M.E. Probert. Paper presented at a symposium held Dec 10-11, 1990,
 Nairobi, Kenya.  Includes references.
 
 Language:  English
 
 Descriptors: Kenya; Legumes; Cropping systems; Rotation; Soil fertility; Maize;
 Cereals
 
 
 128                                                    NAL Call. No.: 23 Au783
 Effects of lupin on soil properties and wheat production.
 Chan, K.Y.; Heenan, D.P.
 Melbourne : Commonwealth Scientific and Industrial Research Organization, 1950-
 ; 1993.
 Australian journal of agricultural research v. 44 (8): p. 1971-1984; 1993.
 Includes references.
 
 Language:  English
 
 Descriptors: New South Wales; Cabt; Triticum; Crop production; Crop yield;
 Lupinus angustifolius; Red soils; Rotations; Soil acidity; Soil organic matter;
 Soil properties; Sustainability
 
 
 129                                                   NAL Call. No.: 75.8 P842
 Effects of moldboard plowing, chisel plowing and rotation crops on the
 Rhizoctonia disease of white potato.
 Leach, S.S.; Porter, G.A.; Rourke, R.V.; Clapham, W.M.
 Orono, Me. : Potato Association of America; 1993 Apr.
 American potato journal v. 70 (4): p. 329-337; 1993 Apr.  Includes references.
 
 Language:  English
 
 Descriptors: Maine; Solanum tuberosum; Rhizoctonia solani; Plant pathogenic
 fungi; Disease control; Plowing; Chiselling; Rotations; Avena sativa; Fagopyrum
 esculentum; Lupinus albus; Pisum sativum; Brassica oleracea; Incidence
 
 
 130                                                    NAL Call. No.: 500 N813
 The effects of no-till and moldboard plow tillage on the movement of nitrates
 and pesticides through the Vadose Zone.
 Bischoff, J.; Bender, A.; Carlson, C.
 Grand Forks, N.D. : The Academy; 1990 Apr.
 Proceedings of the North Dakota Academy of Science v. 44: p. 42; 1990 Apr.
 Includes references.
 
 Language:  English
 
 Descriptors: South Dakota; Avena sativa; Medicago sativa; Zea mays; No-tillage;
 Plowing; Rotations; Movement in soil; Nitrates; Pesticides; Soil water movement
 
 
 131                                                    NAL Call. No.: S590.C63
 Effects of plant residues and environmental factors on phosphorus availability
 in soils.
 Li, G.C.; Mahler, R.L.; Everson, D.O.
 New York, N.Y. : Marcel Dekker; 1990 Mar.
 Communications in soil science and plant analysis v. 21 (5/6): p. 471-491; 1990
 Mar.  Includes references.
 
 Language:  English
 
 Descriptors: Medicago sativa; Pisum sativum; Triticum aestivum; Plant residues;
 Wheat straw; Green manures; Phosphorus; Nutrient availability; Mineralization;
 Decomposition; Soil sorption; Organic matter in soil; Soil temperature; Soil
 water potential; Environmental factors; Interactions
 
 
 132                                                     NAL Call. No.: 4 AM34P
 Effects of previous cropping systems on soil nitrogen and grain sorghum yield.
 Bagayoko, M.; Mason, S.C.; Sabata, R.J.
 Madison, Wis. : American Society of Agronomy; 1992 Sep.
 Journal of the American Society of Agronomy v. 84 (5): p. 862-868; 1992 Sep.
 Includes references.
 
 Language:  English
 
 Descriptors: Nebraska; Glycine max; Rotations; Sorghum bicolor; Soil chemistry;
 Nitrogen content; Grain; Stover; Crop yield
 
 Abstract:  Producers who grow soybean [Glycine max (L.) Merr.] in 3 and 4-yr
 rotations with grain sorghum [Sorghum bicolor (L.) Moench] or other grain crops
 lack information about the duration of grain yield and soil mineral N benefits
 of soybean in crop rotations. To determine the 1-, 2-, and 3-yr
 effects of soybean in crop rotations, an experiment with 8 yr of continuous
 soybean and grain sorghum, and soybean-grain sorghum and grain sorghum-soybean
 rotations combined with fertility treatments of control, N (45 kg ha-1 on
 soybean and 90 kg ha-1 on grain sorghum) and manure (16 Mg ha-1 dry matter
 containing 160 to 250 kg available N ha-1) was terminated in 1987. In 1988 and
 1989 grain sorghum was grown on all plots without fertilizer to determine the
 residual effects of previous cropping system and fertilizer regime on soil
 mineral N, sorghum grain, and stover yield. The experiment was conducted near
 Mead, NE on a Sharpsburg silty clay loam soil (fine montomorillinitic, mesic,
 Typic Arqiudoll). Early in the 1988 season plots with soybean as the previous
 crop had 44 to 50 kg ha-1 more NO3-N in the 150-cm soil profile than did plots
 with continuous grain sorghum. Early in the 1989 season, plots where soybean
 had been grown 2 yr previously had 17 to 23 kg ha-1 more soil NO3-N than did
 continuous grain sorghum plots, while plots 3 yr after soybean had only 3 to 8
 kg ha-1 more soil NO3-N. The yield of grain sorghum in the first, second, and
 third year following soybean was 2 to 3, 0.4 to 1.4, and 0.1 Mg ha-1,
 respectively, greater than the yield of continuous grain sorghum. This study
 indicated that soybean in a crop rotation can contribute to soil NO3-N and
 consequently increase sorghum grain yield for 2 yrs if fertilizer N is
 limiting.
 
 
 133                                                 NAL Call. No.: QL391.N4J62
 Effects of rapeseed and vetch as green manure crops and fallow on nematodes and
 soil-borne pathogens.
 Johnson, A.W.; Goldern, A.M.; Auld, D.L.; Sumner, D.R.
 Lake Alfred, Fla. : Society of Nematologists; 1992 Mar.
 Journal of nematology v. 24 (1): p. 117-126; 1992 Mar.  Includes references.
 
 Language:  English
 
 Descriptors: Brassica napus; Vicia villosa; Cucurbita pepo; Meloidogyne
 incognita; Meloidogyne javanica; Pythium; Rhizoctonia solani; Cropping systems
 
 Abstract:  In a rapeseed-squash cropping system, Meloidogyne incognita race 1
 and M. javanica did not enter, feed, or reproduce in roots of seven rapeseed
 cultivars. Both nematode species reproduced at low levels on roots of the third
 crop of rapeseed. Reproduction of M. incognita and M. javanica was high on
 squash following rapeseed, hairy vetch, and fallow. The application of
 fenamiphos suppressed (P = 0.05) root-gall indices on squash following
 rapeseed, hairy vetch, and fallow; and on Dwarf Essex and Cascade rapeseed, but
 not Bridger and Humus rapeseed in 1987. The incorporation of 30-61 mt/ha green
 biomass of rapeseed into the soil 6 months after planting did not affect the
 population densities of Criconemella ornata, M. incognita, M. javanica, Pythium
 spp., Rhizoctonia solani AG-4; nor did it consistently increase yield of
 squash. Hairy vetch supported larger numbers of M. incognita and M.
 javanica than rapeseed cultivars or fallow. Meloidogyne incognita and M.
 javanica survived in fallow plots in the absence of a host from October to May
 each year at a level sufficient to warrant the use of a nematicide to manage
 nematodes on the following susceptible crop.
 
 
 134                                                   NAL Call. No.: SB610.W39
 Effects of soil-applied AC 263,222 on crops rotated with soybean (Glycine max).
 Wixson, M.B.; Shaw, D.R.
 Champaign, Ill. : The Society; 1992 Apr.
 Weed technology : a journal of the Weed Science Society of America v. 6 (2): p.
 276-279; 1992 Apr.  Includes references.
 
 Language:  English
 
 Descriptors: Mississippi; Glycine max; Rotations; Gossypium hirsutum; Lolium
 multiflorum; Oryza sativa; Sorghum bicolor; Triticum aestivum; Zea mays;
 Imidazolinone herbicides; Residual effects; Phytotoxicity; Crop damage; Weed
 control; Chemical control
 
 
 135                                                    NAL Call. No.: 79.8 W41
 Effects of tillage and application method on clomazone, imazaquin, and
 imazethapyr persistence.
 Curran, W.S.; Liebl, R.A.; Simmons, F.W.
 Champaign, Ill. : Weed Science Society of America; 1992 Jul.
 Weed science v. 40 (3): p. 482-489; 1992 Jul.  Includes references.
 
 Language:  English
 
 Descriptors: Illinois; Glycine max; Rotations; Zea mays; Weed control; Chemical
 control; Clomazone; Imazaquin; Imazethapyr; Persistence; Residual effects; Crop
 damage; Phytotoxicity; No-tillage; Minimum tillage; Plowing; Application
 methods
 
 Abstract:  Effects of tillage and herbicide application method on the
 persistence and residual activity of clomazone, imazaquin, and imazethapyr were
 investigated in a 2-yr field study. Herbicides were applied preemergence and
 preplant incorporated to conventional- and reduced-tillage soybeans in 1987 and
 1988. Herbicide dissipation was monitored using chromatographic and bioassay
 techniques. In 1987, dissipation rates for clomazone, imazaquin, and
 imazethapyr were similar, regardless of tillage system or application method.
 In 1988, all three herbicides applied preplant incorporated dissipated more
 slowly than in preemergence treatments. Corn planted in rotation in 1989
 displayed greater levels of injury in the incorporated treatments for all three
 herbicides. Although herbicide concentrations were similar 322 d
 following application in both tillage treatments in 1989, corn injury was
 greater with imazaquin and imazethapyr and less with clomazone in the
 reduced-tillage plots than in the conventional-tillage treatments.
 
 
 136                                                   NAL Call. No.: 79.8 W412
 Effects of tillage, application time and rate on metribuzin dissipation.
 Sorenson, B.A.; Shea, P.J.; Roeth, F.W.
 Oxford : Blackwell Scientific Publications; 1991 Dec.
 Weed research v. 31 (6): p. 335-345; 1991 Dec.  Includes references.
 
 Language:  English
 
 Descriptors: Nebraska; Glycine max; Zea mays; Triticum aestivum; Rotations;
 Weed control; Metribuzin; Application date; Application methods; Application
 rates; Tillage; No-tillage; Crop yield; Herbicide residues; Silt loam soils
 
 
 137                                                     NAL Call. No.: 450 C16
 Effects of tillage systems and crop rotations on root anda foliar diseases of
 wheat, flax, and peas in Saskatchewan.
 Bailey, K.L.; Mortensen, K.; Lafond, G.P.
 Ottawa : Agricultural Institute of Canada; 1992 Apr.
 Canadian journal of plant science; Revue canadienne de phytotechnie v. 72 (2):
 p. 583-591; 1992 Apr.  Includes references.
 
 Language:  English
 
 Descriptors: Saskatchewan; Linum usitatissimum; Pisum sativum; Triticum
 aestivum; Cultivars; Disease resistance; Fungal diseases; Plant pathogenic
 bacteria; Cultural control; Disease control; Rotations; Tillage
 
 
 138                                                     NAL Call. No.: 450 C16
 The effects of tillage systems and crop rotations on soil water conservation,
 seedling establishment and crop yield.
 Lafond, G.P.; Loeppky, H.; Derksen, D.A.
 Ottawa : Agricultural Institute of Canada; 1992 Jan.
 Canadian journal of plant science; Revue canadienne de phytotechnie v. 72 (1):
 p. 103-115; 1992 Jan.  Includes references.
 
 Language:  English
 
 Descriptors: Saskatchewan; Pisum sativum; Linum usitatissimum; Triticum
 aestivum; Crop production; Crop yield; Seedling growth; Tillage; Stubble
 cultivation; Fallow; Rotations; Soil water; Soil conservation; Soil physical
 properties; Chemical properties
 
 
 139                                                     NAL Call. No.: 450 C16
 The effects of tillage systems on the economic performance of spring wheat,
 winter wheat, flax and field pea production in east-central Saskatchewan.
 Lafond, G.P.; Zentner, R.P.; Geremia, R.; Derksen, D.A.
 Ottawa : Agricultural Institute of Canada; 1993 Jan.
 Canadian journal of plant science; Revue canadienne de phytotechnie v. 73 (1):
 p. 47-54; 1993 Jan.  Includes references.
 
 Language:  English
 
 Descriptors: Saskatchewan; Pisum sativum; Linum usitatissimum; Triticum
 aestivum; Fallow systems; Minimum tillage; No-tillage; Rotations; Stubble
 cultivation; Sustainability; Cost benefit analysis
 
 
 140                                                    NAL Call. No.: 1.9 P69P
 Effects of two-year crop rotations and cultivar resistance on bacterial wilt in
 flue-cured tobacco.
 Melton, T.A.; Powell, N.T.
 St. Paul, Minn. : American Phytopathological Society; 1991 Jul.
 Plant disease v. 75 (7): p. 695-698; 1991 Jul.  Includes references.
 
 Language:  English
 
 Descriptors: North Carolina; Nicotiana tabacum; Cultivars; Pseudomonas
 solanacearum; Plant disease control; Rotations; Continuous cropping; Fallow;
 Glycine max; Zea mays; Festuca; Varietal resistance; Fumigation; Bacterial
 diseases; Wilts; Incidence; Crop yield; Crop quality; Temperature; Moisture
 
 
 141                                                     NAL Call. No.: 10 EX72
 Effects of winged bean on a following maize crop.
 Weil, R.R.; Samaranayake, A.
 Cambridge : Cambridge University Press; 1991 Jul.
 Experimental agriculture v. 27 (3): p. 329-338; 1991 Jul.  Includes
 references.
 
 Language:  English
 
 Descriptors: Sri lanka; Psophocarpus tetragonolobus; Zea mays; Glycine max;
 Rotations; Sequential cropping; Site factors; Ecosystems; Field
 experimentation; Nitrogen fertilizers; Soil properties; Seeds; Crop yield
 
 
 142                                                    NAL Call. No.: SB249.N6
 Effects of winter cover crops on cotton yield and selected soil properties.
 Keisling, T.C.; Scott, H.D.; Waddle, B.A.; Williams, W.; Frans, R.E.
 Memphis, Tenn. : National Cotton Council of America; 1990.
 Proceedings - Beltwide Cotton Production Research Conferences. p. 492-496;
 1990.  Meeting held January 9-14, 1990, Las Vegas, Nevada.  Includes
 references.
 
 Language:  English
 
 Descriptors: Gossypium hirsutum; Cover crops; Secale cereale; Vicia villosa;
 Lupinus albus; Trifolium incarnatum; Crop yield; Soil physical properties
 
 
 143                                                      NAL Call. No.: 30 AD9
 Efficient management of leguminous green manures in wetland rice.
 Singh, Y.; Khind, C.S.; Singh, B.
 San Diego, Calif. : Academic Press; 1991.
 Advances in agronomy v. 45: p. 135-189; 1991.  Literature review.  Includes
 references.
 
 Language:  English
 
 Descriptors: India; Oryza sativa; Green manures; Biomass; Fertilizers;
 Irrigation; Mineralization; Nitrogen cycle; Nutrient availability; Residual
 effects; Soil inoculation; Soil organic matter; Soil properties; Wetlands; Crop
 yield; Literature reviews
 
 
 144                                               NAL Call. No.: S561.6.A82E96
 Estimating 1993 production costs in Arkansas: soybeans--following wheat, loamy
 soils, flood irrigation.
 Windham, T.E.; Stuart, C.A.
 Fayetteville, Ark.?: The Service; 1992 Nov.
 Extension technical bulletin - UA Cooperative Extension Service (184): 8 p.;
 1992 Nov.
 
 Language:  English
 
 Descriptors: Arkansas; Glycine max; Production costs; Estimation; Farm
 budgeting; Loam soils; Flood irrigation; Triticum aestivum; Rotations
 
 
 145                                               NAL Call. No.: S561.6.A82E96
 Estimating 1993 production costs in Arkansas: soybeans--in rice rotation, loamy
 soils, flood irrigation.
 Windham, T.E.; Stuart, C.A.
 Fayetteville, Ark.?: The Service; 1992 Nov.
 Extension technical bulletin - UA Cooperative Extension Service (183): 8 p.;
 1992 Nov.
 
 Language:  English
 
 Descriptors: Arkansas; Glycine max; Production costs; Estimation; Farm
 budgeting; Loam soils; Flood irrigation; Oryza sativa; Rotations
 
 
 146                                               NAL Call. No.: S561.6.A82E96
 Estimating 1993 production costs in Arkansas: soybeans--no-till, following
 wheat, loamy soils, flood irrigation.
 Windham, T.E.; Stuart, C.A.
 Fayetteville, Ark.?: The Service; 1992 Nov.
 Extension technical bulletin - UA Cooperative Extension Service (185): 8 p.;
 1992 Nov.
 
 Language:  English
 
 Descriptors: Arkansas; Glycine max; Production costs; Estimation; Farm
 budgeting; Loam soils; Flood irrigation; Triticum aestivum; No-tillage;
 Rotations
 
 
 147                                                  NAL Call. No.: QH84.8.B46
 Estimating N2 fixation by Sesbania rostrata and S. cannabina (syn. S.
 aculeata) in lowland rice soil by the 15N dilution method.
 Pareek, R.P.; Ladha, J.K.; Watanbe, I.
 Berlin : Springer International; 1990.
 Biology and fertility of soils v. 10 (2): p. 77-88; 1990.  Includes
 references.
 
 Language:  English
 
 Descriptors: Philippines; Sesbania; Sesbania cannabina; Green manures; Isotope
 labeling; Nitrogen; Nitrogen fixation; Paddy soils; Soil fertility; Tropics;
 Mathematical models; Field tests
 
 
 148                                                    NAL Call. No.: SB13.E97
 Estimating total N2 fixation by legumes in long-term rotation studies.
 Papastylianou, I.
 Montrouge Cedex, France : Gauthier-Villars, 1992-; 1993.
 European journal of agronomy : the journal of the European Society for
 Agronomy v. 2 (1): p. 1-10; 1993.  Includes references.
 
 Language:  English
 
 Descriptors: Cyprus; Cabt; Vicia sativa; Nitrogen fixation; Measurement;
 Estimation; Equations; Nitrogen; Use efficiency; Nitrogen fertilizers;
 Rotations; Hordeum vulgare
 
 
 149                                                  NAL Call. No.: S539.5.J68
 Ethephon use on soybean cultivars to enhance establishment of underseeded cover
 crops.
 Moomaw, R.S.; Echtenkamp, G.W.
 Madison, Wis. : American Society of Agronomy; 1991 Apr.
 Journal of production agriculture v. 4 (2): p. 250-255; 1991 Apr.  Includes
 references.
 
 Language:  English
 
 Descriptors: Nebraska; Ethephon; Application rates; Glycine max; Cultivars;
 Crop growth stage; Crop yield; Plant height; Maturity; Canopy; Light
 transmission; Crop establishment; Cover crops; Undersowing; Interplanting; Zea
 mays; Rotations
 
 
 150                                                    NAL Call. No.: S671.A66
 Evaluating seeders for conservation tillage production of peas.
 Wilkins, D.E.; Bolton, F.; Saxton, K.
 St. Joseph, Mich. : American Society of Agricultural Engineers; 1992 Mar.
 Applied engineering in agriculture v. 8 (2): p. 165-170; 1992 Mar.  Includes
 references.
 
 Language:  English
 
 Descriptors: Pacific northwest states of U.S.A.; Drills; Pisum sativum;
 Triticum aestivum; Winter wheat; Rotations; Conservation tillage; Evaluation;
 Comparisons; Performance testing
 
 Abstract:  Two new prototype conservation seeders and an endwheel seeder were
 evaluated in the Pacific Northwest dryland production area for seeding edible
 green peas. Field tests were conducted in 1989 and 1990 on plots with no
 tillage or fall chisel plowing plus secondary field cultivations prior to
 seeding. A strip-till seeder and cross-slot seeder showed good potential for
 spring seeding peas into chisel plowed and untilled wheat stubble. The
 end-wheel seeder performed well in tilled plots. There were no significant
 differences in the amount of soil water lost between seeding and emergence for
 the three seeders. Regardless of the seeder or prior tillage, when seeds were
 placed in contact with soil that had between 50 and 150 kPa (0.5 and 1.5 bars)
 water tension, over 85% of the seeds emerged and established plants.
 
 
 151                                         NAL Call. No.: NBULD3656 1991 S364
 Evaluation of a continuous corn and wheat-corn-soybean rotation under dryland,
 limited and full irrigation..  University of Nebraska--Lincoln thesis :
 Mechanized Agriculture
 Schneekloth, Joel Philip
 1991; 1991.
 x, 179 leaves : ill. ; 28 cm.  Includes bibliographical references.
 
 Language:  English
 
 
 152                                                  NAL Call. No.: SB998.N4N4
 An evaluation of crop plants as hosts for Ditylenchus destructor isolated from
 peanut.
 Basson, S.; De Waele, D.; Meyer, A.J.
 Auburn, Ala. : Organization of Tropical American Nematologists; 1990 Jun.
 Nematropica v. 20 (1): p. 23-29; 1990 Jun.  Includes references.
 
 Language:  English
 
 Descriptors: South  Africa; Arachis hypogaea; Cultivars; Ditylenchus
 destructor; Greenhouse crops; Host parasite relationships; Hosts of plant
 pests; Nematode control; Population density; Rotations
 
 
 153                                                    NAL Call. No.: 1.9 P69P
 Evaluation of crucifer green manures for controlling Aphanomyces root rot of
 peas.
 Muehlchen, A.M.; Rand, R.E.; Parke, J.L.
 St. Paul, Minn. : American Phytopathological Society; 1990 Sep.
 Plant disease v. 74 (9): p. 651-654; 1990 Sep.  Includes references.
 
 Language:  English
 
 Descriptors: Aphanomyces; Plant pathogens; Green manures; Root rots; Pisum
 sativum; Phaseolus vulgaris; Medicago sativa
 
 
 154                                                     NAL Call. No.: 4 AM34P
 Evaluation of soil loss after 100 years of soil and crop management.
 Gantzer, C.J.; Anderson, S.H.; Thompson, A.L.; Brown, J.R.
 Madison, Wis. : American Society of Agronomy; 1991 Jan.
 Agronomy journal v. 83 (1): p. 74-77; 1991 Jan.  Paper presented at the
 Symposium on Long-Term Field Research, October 17-18, 1989.  Includes
 references.
 
 Language:  English
 
 Descriptors: Missouri; Zea mays; Phleum pratense; Avena sativa; Triticum
 aestivum; Trifolium pratense; Long term experiments; Field experimentation;
 Rotations; Continuous cropping; Crop management; Soil management; Erosion;
 Topsoil; Sequential cropping
 
 Abstract:  Sanborn Field, at the University of Missouri-Columbia was
 established in 1888 and is the oldest agricultural experiment field west of the
 Mississippi River. It provides an excellent opportunity to document how long-
 term crop rotations, and soil management influence soil erosion. Analyses of
 topsoil thickness are presented to describe soil remaining after 100 yr of
 cropping in plots planted to continuous corn (Zea mays L.), to continuous
 timothy (Phleum pratense L.). and to a 6-yr rotation cropped sequentially to
 corn, oat (Avena sativa L.), wheat (Triticum aestivum), clover (Trifolium
 pratense), timothy, and timothy. Topsoil thickness was significantly less for
 the continuous corn than the 6-yr rotation or timothy plots after 100 yr of
 cropping. Corn plots had only about 44%, and the rotation plots had only about
 70% as much topsoil as did the timothy plots. The amount of clay in the plow
 layer was significantly higher in the corn plots compared to either the
 rotation or timothy plots suggesting that mixing of clay subsoil within the
 plow layer occurred in corn plots.
 
 
 155                                                     NAL Call. No.: 450 M99
 Evaluation of the "Most Probable Number" (MPN) and wet-sieving methods for
 determining soil-borne populations of endogonaceous mycorrhizal fungi.
 An, Z.Q.; Hendrix, J.W.; Hershman, D.E.; Henson, G.T.
 Bronx, N.Y. : The New York Botanical Garden; 1990 Sep.
 Mycologia v. 82 (5): p. 576-581; 1990 Sep.  Includes references.
 
 Language:  English
 
 Descriptors: Kentucky; Endogone; Glycine max; Festuca arundinacea; Mycorrhizal
 fungi; Soil fungi; Soil flora; Screening; Sieving; Spore germination;
 Rotations; Mycorrhizas; Vesicular arbuscular mycorrhizas
 
 
 156                                                     NAL Call. No.: 10 J822
 Evaluation of the nitrogen contribution of legumes to subsequent cereals.
 Danso, S.K.A.; Papastylianou, I.
 Cambridge : Cambridge University Press; 1992 Aug.
 The Journal of agricultural science v. 119 (pt.1): p. 13-18; 1992 Aug.
 Includes references.
 
 Language:  English
 
 Descriptors: Cyprus; Vicia sativa; Avena sativa; Hordeum vulgare; Isotopes;
 Nitrogen; Nitrogen fertilizers; Nutrient uptake; Rotations; Crop yield; Growth
 
 
 157                                                     NAL Call. No.: 4 AM34P
 Evaluation of the nitrogen fertilizer value of plant materials to spring wheat
 production.
 Mahler, R.L.; Hemamda, H.
 Madison, Wis. : American Society of Agronomy, [1949-; 1993 Mar.
 Agronomy journal v. 85 (2): p. 305-309; 1993 Mar.  Includes references.
 
 Language:  English
 
 Descriptors: Idaho; Cabt; Triticum aestivum; Green manures; Application rates;
 Pisum sativum; Medicago sativa; Wheat straw; Nitrogen; Soil fertility; Crop
 yield; Sustainability
 
 Abstract:  Use of green manure crops has become a preferred alternative source
 of N. The objectives of this 3-yr field study were to evaluate the N supplying
 power of 1, 2, and 3 Mg ha-1 of Austrian winter pea (Pisum sativum ssp.
 arvense L.) Poir), alfalfa (Medicago sativa L.), and wheat (Triticum aestivum
 L.) residue. Residues were incorporated in September and the N contribution of
 each amendment to a subsequent spring wheat crop was calculated. We measured
 inorganic soil N levels and wheat yields in northern Idaho on Latahco silt loam
 fine-silty, mixed, mesic Pachic Ultic Haploxeroll) soils. Soil samples were
 taken during July of each year to determine residual inorganic N. Plant
 material addition and incorporation affected spring wheat yield and soil
 inorganic N level in each study. Pea and alfalfa material applied at 3 Mg ha-1
 resulted in the highest spring wheat yields. Austrian winter pea residue at 3
 Mg ha-1 provided a N credit of 51 to 63 kg ha-1 to spring wheat, compared to 1
 to 36 kg ha-1 for alfalfa applied at the same rate. Based on inorganic soil N
 in July, application of 3 Mg ha-1 of Austrian winter pea, alfalfa, and wheat
 residue provided an N credit of 16 to 24, 21 to 26, and - 1 to - 25 kg ha-1,
 respectively. Average total N credits (soil + plant uptake) for the 3 Mg ha-1
 application of Austrian winter pea, alfalfa, and wheat materials were 76, 47,
 and -35 kg ha-1, respectively. Estimated N recovery of Austrian winter pea
 material after 10 mo of incorporation was 77% (58% in wheat and 19% in soil).
 
 
 158                                                     NAL Call. No.: 4 AM34P
 Evaluation of the nitrogen submodel of CERES-maize following legume green
 manure incorporation.
 Bowen, W.T.; Jones, J.W.; Carsky, R.J.; Quintana, J.O.
 Madison, Wis. : American Society of Agronomy; 1993 Jan.
 Agronomy journal v. 85 (1): p. 153-159; 1993 Jan.  Includes references.
 
 Language:  English
 
 Descriptors: Simulation models; Prediction; Nutrient uptake; Nitrogen; Green
 manures; Nutrient availability; Mineralization; Leaching; Nitrate; Losses from
 soil; Nitrogen balance
 
 Abstract:  Crop simulation models that accurately predict the availability of N
 from decomposing plant residues would provide a powerful tool for evaluating
 legume green manures as potential N sources for nonlegume crops. Using
 measured data from a series of field experiments conducted on an Oxisol in
 central Brazil, we conducted this study to test the N submodel of CERES-Maize
 for its ability to simulate N mineralization, nitrate leaching, and N uptake by
 maize (Zea Mays L.) following the incorporation of 10 different legume green
 manures. Legume or weed residue N at the time of incorporation varied from 25
 to 300 kg ha-1 with C/N ratios varying from 13 to 37. Comparison of predicted
 and measured accumulation of inorganic N in uncropped soil showed that the
 model usually provided a realistic simulation of legume N release, although N
 release was overpredicted for some legumes. For all legumes, both simulated and
 measured data showed that about 60% of the organic N applied was recovered as
 inorganic N within 120 to 150 d after incorporation. To
 realistically simulate N availability when rainfall was excessive, we modified
 the model to account for delayed leaching due to nitrate retention in the
 subsoil. Nitrogen uptake by maize was generally overpredicted at high levels of
 available N. The N submodel was shown to realistically simulate legume N
 release, but further work is needed to determine the importance of subsoil
 nitrate retention in other soils and how best such retention might be
 described in the model.
 
 
 159                                                    NAL Call. No.: 421 J822
 Extent of corn rootworm (Coleoptera: Chrysomelidae) larval damage in corn after
 soybeans: search for the expression of the prolonged dispause trait in
 Illinois.
 Steffey, K.L.; Gray, M.E.; Kuhlman, D.E.
 Lanham, Md. : Entomological Society of America; 1992 Feb.
 Journal of economic entomology v. 85 (1): p. 268-275; 1992 Feb.  Includes
 references.
 
 Language:  English
 
 Descriptors: Illinois; Zea mays; Glycine max; Crop damage; Diabrotica barberi;
 Diapause; Surveys
 
 Abstract:  Surveys were conducted from 1986 through 1989 to determine whether
 prolonged diapause in northern corn rootworm, Diabrotica barberi Smith &
 Lawrence, would lead to subsequent damage by larvae in corn, Zea mays L.,
 planted after soybeans, Glycine max (L.), in Illinois. Overall, 5,406 root
 systems were extracted from 1,100 fields in 35 different counties in northern
 and central Illinois and evaluated for corn rootworm larval injury. The
 incidence of corn rootworm larval damage in corn after soybeans was greatest in
 the central, northeastern, and eastern regions of Illinois, where annual
 rotation of corn with soybeans predominates and where northern corn rootworm
 populations are larger than in other regions of the state. However, only 1.7%
 of the fields surveyed had a mean root rating of greater than or equal to 3.0.
 Only 6.2% of the plants examined had root ratings of greater than or equal to
 3.0. If a theoretical economic injury level for corn rootworm larval damage is
 established at a root damage rating of 4.0, none of the fields surveyed in
 Illinois suffered economic loss as a consequence of rootworm larval injury to
 corn after soybeans. Results from the surveys indicate that prolonged diapause
 rarely causes subsequent economic damage in corn after soybeans in Illinois.
 Corn producers in Illinois rarely need to apply soil insecticides to prevent
 corn rootworm injury, in corn planted after soybeans.
 
 
 160                                                     NAL Call. No.: 4 AM34P
 Fallow and Sesbania effects on soil nitrogen dynamics in lowland rice-based
 cropping systems.
 Buresh, R.J.; Chua, T.T.; Castillo, E.G.; Liboon, S.P.; Garrity, D.P.
 Madison, Wis. : American Society of Agronomy, [1949-; 1993 Mar.
 Agronomy journal v. 85 (2): p. 316-321; 1993 Mar.  Includes references.
 
 Language:  English
 
 Descriptors: Philippines; Cabt; Oryza sativa; Fallow; Rotations; Sesbania;
 Green manures; Nitrate nitrogen; Ammonium nitrogen; Nutrient availability;
 Assimilation; Soil fertility; Flooding; Transplanting; Urea; Application rates;
 Soil depth; Soil water content; Pores; Denitrification; Leaching
 
 Abstract:  Vast areas of rice-growing (Oryza sativa L.) lowlands in Asia are
 fallowed or cropped with non-rice crops for part of the year. Nitrate can
 accumulate during the fallow or non-rice crop, but this nitrate can be lost
 upon flooding for rice production. To determine fallow and green manure crop
 effects on soil nitrate and ammonium dynamics in lowland riceland, a 2-yr field
 study was conducted in the Philippines. Treatments before wet season rice were
 (i) Sesbania rostrata grown for either 45 or 60 d, (ii) weedy
 fallow, and (iii) weed-free fallow. Sesbania rostrata was sown with irrigation
 in late April-early May, rains started in early (1989) or mid-May (1990). Weeds
 and S. rostrata were incorporated after soil flooding on 23 June. Rains
 increased soil water-filled pore space to above 0.75 mL mL-1 between mid-May
 and soil flooding. Weeds and S. rostrata assimilated soil nitrate, as
 evidenced by lower (P < .05) nitrate in those treatments than in the weed-free
 fallow. The decrease in soil nitrate in the weed-free fallow from 24 April to
 before soil flooding (15 kg N ba - 1) was apparently due to denitrification or
 leaching; additional nitrate (19 kg N ha-1 in 1990) disappeared after soil
 flooding. Ammonium-N was rapidly released from incorporated weeds and S.
 rostrata. It reached a maximum by 36 d after incorporation, which correlated r
 = 0.95) with N accumulation by rice at 45 d after transplanting. Results
 suggest that weeds and crops before rice can reduce soil N loss by
 assimilating nitrate-N and then cycling this N through incorporated plant
 residues back to the soil where it is rapidly mineralized and used by rice.
 
 
 161                                                     NAL Call. No.: 4 AM34P
 Fall-seeded legume cover crops for no-tillage corn in the humid East.
 Holderbaum, J.F.; Decker, A.M.; Meisinger, J.J.; Mulford, F.R.; Vough, L.R.
 Madison, Wis. : American Society of Agronomy; 1990 Jan.
 Agronomy journal v. 82 (1): p. 117-124; 1990 Jan.  Includes references.
 
 Language:  English
 
 Descriptors: Maryland; Zea mays; No-tillage; Cover crops; Winter; Sowing date;
 Autumn; Crop mixtures; Vicia villosa; Vicia; Trifolium incarnatum; Pisum
 sativum; Vicia sativa; Trifolium subterraneum; Trifolium vesiculosum; Trifolium
 hirtum; Trifolium pratense; Medicago sativa; Secale cereale; Melilotus
 officinalis; Hordeum vulgare; Triticum aestivum; Nitrogen content; Crop yield;
 Grain; Nitrogen uptake
 
 Abstract:  No-tillage systems utilizing winter cover crops can reduce erosion
 and leaching losses. Fall-seeded legumes can also supply significant amounts of
 N to subsequent corn (Zea mays L.) crops. The suitability of 14 fall-seeded
 legumes, three small grains and four legume/grass mixtures was evaluated for
 winter covers from 1982 through 1985 on Matapeake silt loam (fine-loamy, mixed,
 mesic, Typic Hapludult) and Mattapex silt (fine-silty, mixed mesic, Aqualfic
 Normuldult) Coastal Plain soils as well as Delanco silt loam and Chester silt
 loam (fine-loamy, mixed, mesic, Aquic Hapludult) Piedmont soils. Hairy vetch
 (Vicia villosa Roth), crimson clover (Trifolium incarnatum L.) and Austrian
 winter peas [Pisum sativum (L.) Poir.] were the most promising cover crops.
 Fall growth and early soil coverage was highest with crimson and lowest with
 vetch which had higher winter survival and spring growth. Peas and, to a lesser
 extent, crimson clover stands were damaged in some years by Sclerotinia
 trifoliorum Eriks. In some years top growth of vetch contained up to 350 kg
 N/ha. While N concentration varied among species, total N production was
 determined more by dry matter yield. Legume cover crops had a greater
 influence on corn grain yields on the heavier textured soils and longer
 growing season of the Coastal Plain. In 1985, N contribution to the subsequent
 corn crop was reduced when small grains were seeded with annual legumes.
 Results from these studies show that winter annual legumes can reduce N costs
 while providing better soil protection during winter months.
 
 
 162                                                  NAL Call. No.: S605.5.A43
 Farm program impacts on incentives for greenmanure rotations.
 Young, D.L.; Painter, K.M.
 Greenbelt, Md. : Institute for Alternative Agriculture; 1990.
 American journal of alternative agriculture v. 5 (3): p. 99-105; 1990.
 Includes references.
 
 Language:  English
 
 Descriptors: Alternative farming; Sustainability; Rotations; Green manures;
 Agricultural policy; Legislation; Economic analysis; Profitability; Costs;
 Returns; Seasonal variation; Incentives
 
 Abstract:  Farm programs influence the profitability of a crop rotation
 through five effects: (1) a deficiency payment (DP) effect, (2) an acreage
 reduction (ARP) effect, (3) a base effect, (4) a crop price effect, and (5) a
 risk reduction effect. This study initially examines ARP and DP effects of the
 1985 Farm Bill on the relative profitability Of a low-input rotation and a
 grain-intensive conventional rotation in Washington state over 1986-1990. In
 years of low deficiency payments or high foregone returns from ARP land, the
 low-input green manure rotation was competitive with the conventional rotation
 but lost its advantage in years of low ARP costs or high deficiency payments.
 Long-run incentives to maintain wheat base introduced a consistent bias
 against the low-input green manure rotation. Planting flexibility options
 proposed during the 1990 Farm Bill debate could reduce farm program barriers to
 green manure and other low-input rotations. The Bush Administration's
 Normal Crop Acreage (NCA) proposal, which was not accepted in the 1990
 legislation, would have largely eliminated base erosion for the green manure
 rotation in this study. More importantly, non-ARP green manure acreage would
 have qualified for deficiency payments under the NCA, thereby sharply
 increasing the low-input rotation's relative profitability. Proposals like the
 NCA might receive further attention in the future due to environmental
 concerns, fiscal pressures, or possible trade agreements requiring
 multilateral phaseout of agricultural subsidies coupled to commodities.
 
 
 163                                                    NAL Call. No.: 23 AU792
 Farming duplex soils: a farmer's perspective.
 Edwards, I.
 East Melbourne : Commonwealth Scientific and Industrial Research Organization;
 1992.
 Australian journal of experimental agriculture v. 32 (7): p. 811-814; 1992.
 Special issue: Crop production on duplex soils.  Includes references.
 
 Language:  English
 
 Descriptors: Western australia; Trifolium subterraneum; Triticum; Crop
 management; Duplex soils; Minimum tillage; Rotations; Sustainability; Weed
 control; Fungus control; Gaeumannomyces graminis; Crop yield
 
 
 164                                                   NAL Call. No.: 56.8 J822
 Farming systems' influence on soil properties and crop yields.
 Rickerl, D.H.; Smolik, J.D.
 Ankeny, Iowa : Soil and Water Conservation Society of America; 1990 Jan.
 Journal of soil and water conservation v. 45 (1): p. 121-125; 1990 Jan.
 Includes references.
 
 Language:  English
 
 Descriptors: Medicago sativa; Zea mays; Glycine max; Triticum aestivum; Farming
 systems; Soil properties; Crop yield; Agriculture; Sustainability; Crop
 residues; Rotations; Conservation tillage; Drought injury
 
 
 165                                                  NAL Call. No.: S539.5.J68
 Farm-level economic and environmental impacts of eastern Corn Belt cropping
 systems.
 Foltz, J.C.; Lee, J.G.; Martin, M.A.
 Madison, WI : American Society of Agronomy, c1987-; 1993 Apr.
 Journal of production agriculture v. 6 (2): p. 290-296; 1993 Apr.  Includes
 references.
 
 Language:  English
 
 Descriptors: Corn belt states of U.S.A.; Cabt; Zea mays; Medicago sativa;
 Glycine max; Microeconomic analysis; Economic impact; Alternative farming;
 Environmental impact; Rotations; Continuous cropping; Simulation models;
 Computer simulation; Erosion; Runoff; Pesticides; Water pollution
 
 
 166                                                   NAL Call. No.: 56.8 C162
 Fate of N applied as green manure or ammonium fertilizer to soil subsequently
 cropped with spring wheat at three sites in western Canada.
 Janzen, H.H.; Bole, J.B.; Biederbeck, V.O.; Slinkard, A.E.
 Ottawa : Agricultural Institute of Canada; 1990 Aug.
 Canadian journal of soil science v. 70 (3): p. 313-323; 1990 Aug.  Includes
 references.
 
 Language:  English
 
 Descriptors: Green manures; Nitrogen; Ammonium fertilizers; Annuals; Legumes;
 Lens culinaris; Triticum aestivum; Lathyrus tingitanus; Nitrogen
 mineralization; Rotation; Cropping systems
 
 
 167                                                     NAL Call. No.: 26 T754
 Fertilizer phosphorus and potassium equivalents of some green manures for
 potato in alluvial soils of Punjab.
 Sharma, R.C.; Sharma, H.C.
 London : Butterworth-Heinemann; 1990 Jan.
 Tropical agriculture v. 67 (1): p. 74-76; 1990 Jan.  Includes references.
 
 Language:  English
 
 Descriptors: Indian punjab; Solanum tuberosum; Crotalaria juncea; Green
 manures; Sesbania aculeata; Phosphorus fertilizers; Potassium fertilizers;
 Tubers; Crop yield; Alluvial soils
 
 
 168                                                 NAL Call. No.: 281.8 F2226
 Financial projections for a case Illinois grain farm under three tillage
 scenarios.
 Koenigstein, K.W.; Hornbaker, R.H.
 Urbana, Ill. : The Service; 1990 Oct.
 Farm economics facts and opinions - University of Illinois, Department of
 Agricultural Economics, Cooperative Extension Service (90-18): 5 p.; 1990 Oct.
 
 Language:  English
 
 Descriptors: Illinois; Glycine max; Maize; Tillage; No-tillage; Farm machinery;
 Farm inputs; Farm comparisons; Projections; Simulation models; Case studies
 
 
 169                                                 NAL Call. No.: QL391.N4J62
 Fitness components and selection of biotypes of Heterodera glycines.
 Sipes, B.S.; Schmitt, D.P.; Barker, K.R.
 Lake Alfred, Fla. : Society of Nematologists; 1992 Sep.
 Journal of nematology v. 24 (3): p. 415-424; 1992 Sep.  Includes references.
 
 Language:  English
 
 Descriptors: North Carolina; Glycine max; Heterodera glycines; Pest resistance;
 Cultivars; Host parasite relationships; Plant parasitic nematodes
 
 Abstract:  Survival of biotypes of Heterodera glycines was studied in
 microplots and in the field. The field population was subjected to various
 cropping sequences. Viability of eggs overwintered in microplots was determined
 each spring by percentage hatch, percentage of hatched eggs penetrating roots,
 and numbers of females developing on Peking and PI 88788 soybeans. Eggs from
 the field were collected in the spring and fall and assayed for ability to
 develop on Peking and PI 88788. Hatch of isolates overwintered in the
 microplots averaged 13% in May 1989 and 19% in 1990. No differences in hatch
 were detected among the isolates in 1989. Numbers of juveniles penetrating
 susceptible roots averaged less than 20% of the hatched eggs each year. An
 isolate of a biotype parasitic on susceptible soybeans and the resistant
 soybean PI 88788 penetrated roots more successfully than other biotypes. A
 second isolate from North Carolina, parasitic on susceptible soybeans. PI
 98788, and the resistant soybean Peking experienced selection against
 development on Peking during two winters. Only 17% of the expected numbers of
 females developed on Peking from this isolate. In the microplot experiment,
 parasitism of PI 88788 and Peking had a selective disadvantage (selection
 coefficient) of s = 0.29 and 0.62 over all isolates, respectively. In the field
 experiment, the relative numbers of cysts on Peking and PI 88788 increased
 between the spring and fall on soybean, then decreased over the winter and
 under corn. Selection coefficients against parasitism of PI 88788 and Peking
 averaged 0.19 and 0.3 in the field population. In neither experiment did
 juveniles lose their ability to parasitize susceptible soybean.
 
 
 170                                             NAL Call. No.: QR89.7.A34 1990
 Five years of research on improved fallow in the semi-arid highlands of
 Rwanda.
 Balasubramanian, V.; Sekayange, L.
 Chichester : Wiley; 1992.
 Biological nitrogen fixation and sustainability of tropical agriculture : proc
 of the 4th International Conf of the African Assoc for Biological Nitrogen
 Fixation, held at the Int Inst of Trop Agric, Nigeria, 24-28 Sept 1990. p.
 405-422; 1992.  Includes references.
 
 Language:  English
 
 Descriptors: Rwanda; Improved fallow; Leguminosae; Rotations; Nitrogen
 fixation; Soil fertility
 
 
 171                                                  NAL Call. No.: S539.5.J68
 Forage legume-small grain intercrops: nitrogen production and response of
 subsequent corn.
 Hesterman, O.B.; Griffin, T.S.; Williams, P.T.; Harris, G.H.; Christenson, D.R.
 Madison, Wis. : American Society of Agronomy; 1992 Jul.
 Journal of production agriculture v. 5 (3): p. 340-348; 1992 Jul.  Includes
 references.
 
 Language:  English
 
 Descriptors: Michigan; Triticum aestivum; Winter wheat; Avena sativa; Zea mays;
 Medicago sativa; Trifolium pratense; Cover crops; Intercropping; Crop yield;
 Sowing; Nitrogen; Soil fertility; Available water; Spatial variation;
 Geographical distribution; Precipitation; Seasonal variation
 
 
 172                                                     NAL Call. No.: 450 C16
 Forage-corn production and N-fertilizer replacement values following 1 or 2
 years of legumes.
 Pare, T.; Chalifour, F.P.; Bourassa, J.; Antoun, H.
 Ottawa : Agricultural Institute of Canada; 1993 Apr.
 Canadian journal of plant science; Revue canadienne de phytotechnie v. 73 (2):
 p. 477-493; 1993 Apr.  Includes references.
 
 Language:  English
 
 Descriptors: Zea mays; Vicia faba; Glycine max; Rotations; Nitrogen content;
 Nutrient content; Nitrogen fertilizers; Nutrient availability; Application
 rates; Ammonium nitrate; Crop yield; Sequential cropping; Nutrient uptake; Dry
 matter accumulation
 
 
 173                                                    NAL Call. No.: 421 J822
 Foraging preference of red imported fire ants (Hymenoptera: Formicidae) among
 three species of summer cover crops and their extracts.
 Kaakeh, W.; Dutcher, J.D.
 Lanham, Md. : Entomological Society of America; 1992 Apr.
 Journal of economic entomology v. 85 (2): p. 389-394; 1992 Apr.  Includes
 references.
 
 Language:  English
 
 Descriptors: Indigofera hirsuta; Sesbania exaltata; Vigna unguiculata; Insect
 repellents; Plant extracts; Solenopsis invicta; Feeding preferences; Foraging
 
 Abstract:  Foraging preference of red imported fire ant, Solenopsis invicta
 Buren, among three species of summer cover crops, sesbania, Sesbania exaltata
 (Rafinesque-Schmaltz) Cory; hairy indigo, Indigofera hirsuta L.; and cowpea,
 Vigna unguiculata (L.) Walpers, was evaluated in the greenhouse using choice
 and no-choice tests. Ants derived a large part of their nutrients from aphid
 honeydew, and ant workers differed in their response to plant species in the
 presence or absence of cowpea aphid. Ants preferred cowpea > indigo > sesbania
 when these plants were infested with cowpea aphids, whereas ants showed no
 preference between cowpea and indigo when plants were kept free of cowpea
 aphids. Sesbania showed almost 100% repellency, to ants for 8 d, whether these
 plants were infested or kept free of aphids. In a pickup bioassay for detecting
 any discrimination among plants by ants, leaf disks from noninfested leaves of
 cowpea and hairy indigo were picked up more readily than those from sesbania.
 Response of ants to extracts differed significantly among plants. Sesbania
 extract repelled and caused mortality in the red imported fire ant. Ethanol
 extract of sesbania caused higher ant mortality than the water extract.
 
 
 174                                                 NAL Call. No.: 290.9 AM32T
 Furrow irrigation performance in reduced-tillage systems.
 Yonts, C.D.; Smith, J.A.; Bailie, J.E.
 St. Joseph, Mich. : American Society of Agricultural Engineers; 1991 Jan.
 Transactions of the ASAE v. 34 (1): p. 91-96; 1991 Jan.  Includes references.
 
 Language:  English
 
 Descriptors: Nebraska; Furrow irrigation; Minimum tillage; Moldboards; Plowing;
 Rotary cultivation; Rotations; Zea mays; Phaseolus vulgaris; Beta vulgaris
 
 Abstract:  Irrigation performance parameters including furrow advance time and
 application efficiency were compared among three tillage systems: moldboard
 plow, rotary strip till, and minimum till. A three crop rotation of corn, dry
 beans and sugarbeets was used in the study. Data was collected in 1985 and 1987
 primarily during the first and second irrigations for all three crops each year
 using two furrow flow rates for each test. Irrigation advance time was
 increased due to reduced tillage in 25% of the trials conducted. The plow
 system increased furrow advance time when compared to the reduced till systems
 in light residue cover situations and during the first irrigation. The reduced-
 till systems, with at least 27% surface cover, influenced furrow advance
 greater than the conventional plow system. Surface residue levels of 48% or
 more prior to the first irrigation were found to be unacceptable for adequate
 furrow irrigation performance, unless furrow length is reduced, due to the
 difficulty in advancing water through the field.
 
 
 175                                           NAL Call. No.: KyUThesis 1991
 An Glomales mycorrhizal community associated with soybean as influenced by crop
 rotation and soil fumigation.
 An, Zhi-qiang, 1991; 1991.
 vii, 108 leaves : ill. ; 29 cm.  Includes vita and abstract.  Includes
 bibliographical references (l. 98-107).
 
 Language:  English
 
 Descriptors: Soybean; Crop rotation; Mycorrhizas
 
 
 176                                                    NAL Call. No.: 56.9 SO3
 Grain sorghum-soybean rotation and fertilization influence on vesicular-
 arbuscular mycorrhizal fungi.
 Ellis, J.R.; Roder, W.; Mason, S.C.
 Madison, Wis. : The Society; 1992 May.
 Soil Science Society of America journal v. 56 (3): p. 789-794; 1992 May.
 Includes references.
 
 Language:  English
 
 Descriptors: Nebraska; Vesicular arbuscular mycorrhizas; Glycine max; Sorghum
 bicolor; Rotations; Continuous cropping; Colonization; Roots; Growth; Ammonium
 nitrate; Cattle manure
 
 Abstract:  Vesicular-arbuscular mycorrhizal fungi (VAMF) can reduce plant
 stress resulting from nutrient deficiencies, drought, and other factors. The
 objective of this work was to measure the effect of soybean [Glycine max (L.)
 Merr.] and grain sorghum [Sorghum bicolor (L.) Moench] rotation and
 fertilization on plant response and VAMF root colonization and diversity, and
 relate effects to soil environment. Fertilizer treatments consisted of no
 fertilizer, N, and manure. Rooting densities correlated with previous crop,
 VAMF colonization, and soil NO3. Root colonization by VAMF was affected by
 previous crop, rooting density, N fertilization, soil P, and water-filled pore
 space. Root colonization by VAMF ranged from 93% at 15 cm to 15% at the 120-cm
 soil depth. Root density and VAMF colonization were least when soybean was
 grown the previous year and manure was applied. Root colonization by VAMF for
 control, N, and manure treatments were 54, 53, and 30%, respectively, for
 continuous soybean and 61, 55, and 44%, respectively, for soybean from rotation
 plots. Root colonization by VAMF for control, N, and manure treatments were 69,
 59, and 54%, respectively, for continuous grain sorghum and 56, 48, and 31%,
 respectively, for grain sorghum from rotation plots. These agricultural soils
 contained a diverse mixture of 26 VAMF species, which is probably a major
 factor in the region's soil productivity. Plants stressed due to cropping
 system or fertilizer practice have greater VAMF colonization and VAMF activity.
 A diverse VAMF population could increase the ability of VAMF to respond to
 different stresses.
 
 
 177                                                    NAL Call. No.: 23 AU792
 Grain yield of wheat in rotation with pea, vetch or medic grown with three
 systems of management.
 Silsbury, J.H.
 East Melbourne : Commonwealth Scientific and Industrial Research Organization;
 1990.
 Australian journal of experimental agriculture v. 30 (5): p. 645-649; 1990.
 Includes references.
 
 Language:  English
 
 Descriptors: South australia; Triticum; Medicago truncatula; Pisum sativum;
 Vicia sativa; Crop yield; Harvesting; Nitrogen fertilizers; Plowing; Rotations;
 Soil fertility
 
 
 178                                                     NAL Call. No.: 26 T754
 Grain yield responses in rice to eight tropical green manures.
 Meelu, O.P.; Morris, R.A.; Furoc, R.E.; Dizon, M.A.
 London : Butterworth-Heinemann; 1992 Apr.
 Tropical agriculture v. 69 (2): p. 133-136; 1992 Apr.  Includes references.
 
 Language:  English
 
 Descriptors: Philippines; Oryza sativa; Sesbania cannabina; Crotalaria juncea;
 Green manures; Legumes; Nitrogen fertilizers; Biomass production; Crop yield
 
 
 179                                                  NAL Call. No.: QH84.8.B46
 Green manure production of Azolla microphylla and Sesbania rostrata and their
 long-term effects on rice yields and soil fertility.
 Ventura, W.; Watanabe, I.
 Berlin : Springer International; 1993.
 Biology and fertility of soils v. 15 (4): p. 241-248; 1993.  Includes
 references.
 
 Language:  English
 
 Descriptors: Philippines; Oryza sativa; Flooded rice; Aeschynomene; Azolla;
 Sesbania; Soil fertility; Crop yield; Decomposition; Green manures; Organic
 fertilizers; Urea fertilizers
 
 
 180                                                   NAL Call. No.: 64.8 C883
 Green-manure legume effects on soil nitrogen, grain yield, and nitrogen
 nutrition of wheat.
 Badaruddin, M.; Meyer, D.W.
 Madison, Wis. : Crop Science Society of America; 1990 Jul.
 Crop science v. 30 (4): p. 819-825; 1990 Jul.  Includes references.
 
 Language:  English
 
 Descriptors: Triticum aestivum; Rotations; Cultivars; Medicago sativa; Vicia
 villosa; Melilotus officinalis; Trifolium pratense; Herbage; Nitrogen content;
 Soil fertility; Crop yield; Yield components; Grain; Green manures; Fallow;
 Nitrogen uptake; Nitrogen recovery
 
 Abstract:  Knowledge of legume N production and legume effects on subsequent
 crop yield and quality is necessary to encourage legume use instead of the
 traditional fallow on set-aside land. Objectives of these studies were to: (i)
 compare seeding-year herbage and N yields of five forage legume species, (ii)
 determine soil NO3-N status in the spring following green-manure legume crops,
 and (iii) evaluate effects of green-manure legumes on grain yield, grain yield
 components, and N nutrition of the subsequent wheat (Triticum aestivum L.) crop
 when fertilized with 0, 75, and 150 Kg N ha-1. Field experiments were conducted
 on a Fargo silty clay (fine-montmorilloritic, frigid Vertic Haplaquoll) at
 Fargo and on a Perella-Bearden silty clay loam (fine, silty, mixed, frigid
 Typic Haplaquoll, fine silty, frigid Aeric Calciaquoll) near Prosper, ND,
 during 1984 to 1986. All legume species had equal herbage and N yields across
 the four environments and were greater than the wheat-straw check. Accumulated
 legume herbage and fall regrowth were incorporated into the soil in late fall.
 Spring soil NO3-N following Terra Verde alfalfa (Medicago sativa L.) and hairy
 vetch (Vicia villosa Roth.) was equal to the fallow check and greater than the
 soil NO3-N following the wheat check or other legume species. Grain yield,
 grain N, and N uptake of unfertilized wheat following the legume treatments
 generally were similar to those following fallow and wheat fertilized with 150
 kg N ha-1. Increases in all grain yield components following legumes
 contributed to this yield advantage.Efficiency and utilization of N generally
 were greater following a green-manure crop than following either fallow or
 wheat checks. This study suggests that green-manure legumes should be
 considered as an alternative to fallow on set-aside land in higher moisture
 areas.
 
 
 181                                                 NAL Call. No.: S592.7.A1S6
 Growth and N2-fixation of two stem-nodulating legumes and their effect as green
 manure on lowland rice.
 Becker, M.; Ladha, J.K; Ottow, J.C.G.
 Exeter : Pergamon Press; 1990.
 Soil biology and biochemistry v. 22 (8): p. 1109-1119; 1990.  Includes
 references.
 
 Language:  English
 
 Descriptors: Sesbania; Aeschynomene; Growth rate; Nitrogen fixation; Stem
 nodules; Green manures; Lowland areas; Oryza sativa
 
 
 182                                                    NAL Call. No.: 56.9 SO3
 Growth characteristics of legume cover crops in a semiarid environment.
 Power, J.F.
 Madison, Wis. : The Society; 1991 Nov.
 Soil Science Society of America journal v. 55 (6): p. 1659-1663; 1991 Nov.
 Includes references.
 
 Language:  English
 
 Descriptors: North Dakota; Legumes; Cover crops; Green manures; Semiarid
 climate; Seasonal growth; Planting date; Temporal variation; Stand
 characteristics; Growth rate; Dry matter accumulation; Nitrogen fixation;
 Nitrogen; Nutrient uptake; Water use efficiency; Nitrogen content; Climatic
 factors; Precipitation; Dry farming
 
 Abstract:  To select the best legume cover crop to grow for a given cropping
 situation, the producer needs knowledge of relative growth rates, N2-fixation
 and N-uptake rates, and water use for various potential planting dates. Such an
 experiment was conducted for 2 yr at Mandan, ND, in which 10 legume species
 were planted on or shortly after the first day of May, June, July, and August
 each year. Soil and plant samples were collected periodically after each
 planting date to evaluate rates of dry-matter production, N accumulation, and
 water use. Potential N2-fixation rate was measured in one season only. For the
 first 40 to 90 d after planting, large-seeded annuals such as faba bean (Vicia
 faba L.) field pea (Pisum sativum L.), and soybean (Glycine max [L] Merr.)
 generally exhibited most rapid growth, N accumulation, and water use (these
 three parameters were generally closely related for all samplings). With more
 than 90 d growth, species such as Korean lespedeza (Lespedeza stipulacea
 Maxim.), yellow sweet clover (Melilotus officianalis L.), and alfalfa (Medicago
 sativa L.) also began to exhibit rapid growth. One surprising result was the
 outstanding growth of May-planted subterranean clover (Trifolium subterraneum
 L.) in one (ample moisture) of the two seasons. For the shorter growth periods,
 faba bean exhibited good growth characteristics at all planting dates, and
 field pea was satisfactory at most. July and August planting of slower growing
 species generally resulted in relatively little growth by the end of the
 season. In most instances, water-use efficiency was greatest for the May
 planting, and highest values were often recorded for field pea, faba bean, and
 subterranean clover. These results identify those legume species best adapted
 for a given planting date and duration of growth under the climatic conditions
 of this experiment.
 
 
 183                                                     NAL Call. No.: 4 AM34P
 Growth, yield, and yield components of lupin cultivars.
 Lopez-Bellido, L.; Fuentes, M.
 Madison, Wis. : American Society of Agronomy; 1990 Nov.
 Agronomy journal v. 82 (6): p. 1050-1056; 1990 Nov.  Includes references.
 
 Language:  English
 
 Descriptors: Spain; Lupinus albus; Lupinus luteus; Lupinus angustifolius;
 Lupinus mutabilis; Cultivars; Growth rate; Dry matter accumulation; Leaf area
 index; Leaf duration; Crop yield; Harvest index; Crop quality; Protein content;
 Fats; Varietal reactions; Mediterranean climate; Adaptation; Acid soils
 
 Abstract:  The cultivation of Lupin, Lupinus spp., as a protein source for
 animal feed and as a way of improving soil fertility is of interest for crop
 rotation under rainfed Mediterranean climatic conditions and poor acid soils.
 The adaptation of a cultivar from each one of the four cultivated species of
 lupin: L. albus (L.), L. luteus (L.), L. angustifolius (L.), and L. mutabilis
 (Sweet) has been studied. A comparative analysis of their growth (dry matter,
 growth rates, leaf area index (LAI) and leaf area duration (LAD), yield, yield
 components and harvest index (HI), protein, and fat content was carried out in
 the Guadalquivir Valley in southern Spain on a river terrace with Haploxeralf
 soil and a loamy clay texture. Variations in climatic conditions markedly
 influenced the duration of the different growth stages, accumulation of dry
 matter, leaf area and yield of the different cultivars. Lupinus albus was the
 species best adapted to the conditions of the survey, distributing its dry
 matter better and showing better growth indexes and higher grain yield. Lupinus
 mutabilis proved to be inadvisable for autumn sowings under the ecological
 conditions of the area. It was sensitive to the cold during its vegetative
 stage and performed poorly. The values found for the L. luteus and the
 angustifolius cultivars were less than those registered in other areas where it
 is a traditional crop. Better growth and grain yield was obtained with them
 when emergence was in early rather than late autumn.
 
 
 184                                                   NAL Call. No.: HD1750.W4
 A GSD estimation of the relative worth of cover crops in cotton production
 systems.
 Giesler, G.G.; Paxton, K.W.; Millhollon, E.P.
 Bozeman, Mont. : Western Agricultural Economics Association; 1993 Jul.
 Journal of agricultural and resource economics v. 18 (1): p. 47-56; 1993 Jul.
 Includes references.
 
 Language:  English
 
 Descriptors: Louisiana; Cover crops; Crop production; Stochastic processes;
 Feasibility; Risk; Environmental impact; Farmers' attitudes; Value theory; Time
 series; Crop yield; Nitrogen fertilizers; Grasses; Legumes; Returns; Low input
 agriculture; Traditional farming
 
 
 185                                                    NAL Call. No.: S601.A34
 Herbicide and rotation effects on soil and rhizosphere microorganisms and crop
 yields.
 Moorman, T.B.; Dowler, C.C.
 Amsterdam : Elsevier; 1991 May.
 Agriculture, ecosystems and environment v. 35 (4): p. 311-325; 1991 May.
 Includes references.
 
 Language:  English
 
 Descriptors: Georgia; Zea mays; Glycine max; Trifluralin; Alachlor; Crop
 production; Soil fertility; Rotations; Rhizosphere; Pseudomonas; Bacteria;
 Fusarium; Pythium; Experimental stations
 
 
 186                                                   NAL Call. No.: SB610.W39
 Hogpotato (Hoffmanseggia glauca) control with herbicides and rotational crop
 response.
 Westerman, R.B.; Murray, D.S.; Castner, E.P.
 Champaign, Ill. : The Weed Science Society of America; 1993 Jul.
 Weed technology : a journal of the Weed Science Society of America v. 7 (3): p.
 650-656; 1993 Jul.  Includes references.
 
 Language:  English
 
 Descriptors: Oklahoma; Cabt; Triticum aestivum; Sorghum bicolor; Gossypium
 hirsutum; Rotations; Perennial weeds; Weed control; Chemical control;
 Leguminosae; Triclopyr; Dicamba; Glyphosate; Imazapyr; Tebuthiuron; 2,4-d;
 Residual effects; Persistence; Sequential cropping; Bioassays; Crop damage;
 Abiotic injuries; Phytotoxicity
 
 
 187                                                  NAL Call. No.: SB998.N4N4
 Horsebean (Canavalia ensiformis) and crotalaria (Crotalaria spectabilis) for
 the management of Meloidogyne spp.
 Rodriguez-Kabana, R.; Pinochet, J.; Robertson, D.G.; Weaver, C.F.; King, P.S.
 Auburn, Ala. : Organization of Tropical American Nematologists; 1992 Jun.
 Nematropica v. 22 (1): p. 29-35; 1992 Jun.  Includes references.
 
 Language:  English
 
 Descriptors: Alabama; Spain; Canavalia ensiformis; Crotalaria spectabilis;
 Meloidogyne arenaria; Meloidogyne incognita; Meloidogyne javanica; Nematode
 control; Rotations
 
 
 188                                         NAL Call. No.: MnSUThesis stp whit
 Host-specific pathogens and the corn/soybean rotation effect.
 Whiting, Kelly Reid
 1991; 1991.
 iii, 75 leaves : ill. ; 29 cm.  Includes bibliographical references.
 
 Language:  English
 
 
 189                                                   NAL Call. No.: 64.8 C883
 Host-specific pathogens do not account for the corn-soybean rotation effect.
 Whiting, K.R.; Crookston, R.K.
 Madison, Wis. : Crop Science Society of America, 1961-; 1993 May.
 Crop science v. 33 (3): p. 539-543; 1993 May.  Includes references.
 
 Language:  English
 
 Descriptors: Minnesota; Cabt; Glycine max; Zea mays; Rotations; Plant disease
 control; Cultural control; Phialophora gregata; Diaporthe phaseolorum; Disease
 prevalence; Rhizoctonia solani; Incidence; Crop yield; Seeds
 
 Abstract:  Soybean [Glycine max (L.) Merr.) generally yields more when rotated
 with another crop rather than grown continuously. The specific reasons for this
 yield response are unknown. The objective of this study was to investigate the
 extent to which a soybean-corn (Zea mays L.) rotation limited the buildup of
 host-specific pathogens of soybean, and to evaluate whether plant diseases were
 involved in the rotation effect. Incidence and severity of seven diseases and
 seed yield were recorded at two locations in the field in 1987 and 1988 for
 soybean maintained in four cropping sequences ranging from annual alternation
 with corn to 1,2, or 5 yr of continuous cropping. Brown stem rot (BSR) caused
 by the fungus Phialophora gregata (Allington & D.W. Chamberlain) W. Gams was
 found to be the most prevalent disease during both years and at both locations.
 Rhizoctonia root rot (Rhizoctonia solani Kuhn) and stem canker (Diaporthe
 phaseolorum Cooke. & Ellis Sacc. var. Cavlivorn Athow & Caldwell) were noted in
 1987 at both locations among <5% of all plants monitored. The BSR-prevalence
 ratings were relatively high (mean 60%) for Hodgson 78, a susceptible cultivar,
 and relatively low (mean 22%) for BSR101, a resistant cultivar. Seed yield data
 from the various cropping sequences for the two cultivars indicated no clear
 relationship between BSR severity and seed yield. In 1987, rotation with corn
 resulted in a yield benefit to both cultivars. In 1998, both yield and
 development of BSR were adversely affected by drought. A comparison of the seed
 yield of severely infected and uninfected plants within cropping sequence
 indicated that BSR had a minimal effect on soybean yield in 1998. Therefore,
 within the conditions of this study, the yield benefit to soybean from rotation
 with corn did not appear to be due to the reduced incidence of plant diseases.
 
 
 190                                                      NAL Call. No.: S1.N32
 How to choose a soil-building legume.
 Sarrantonio, M.
 Emmaus, Pa. : Rodale Institute; 1991 Jul.
 The New farm. p. 23-25; 1991 Jul.  Paper presented at a Rodale Institute "Take
 Charge" workshop, Winter, 1990, Kutztown, Pennsylvania.
 
 Language:  English
 
 Descriptors: Leguminosae; Cover crops
 
 
 191                                                   NAL Call. No.: SB610.W39
 Imazaquin, chlorimuron, and fomesafen may injure rotational vegetables and
 sunflower (Helianthus annuus).
 Johnson, D.H.; Talbert, R.E.
 Champaign, Ill. : The Weed Science Society of America; 1993 Jul.
 Weed technology : a journal of the Weed Science Society of America v. 7 (3): p.
 573-577; 1993 Jul.  Includes references.
 
 Language:  English
 
 Descriptors: Arkansas; Cabt; Helianthus annuus; Rotations; Spinacia oleracea;
 Citrullus lanatus; Phaseolus vulgaris; Cucumis sativus; Weed control; Chemical
 control; Imazaquin; Chlorimuron; Fomesafen; Metribuzin; Herbicide mixtures;
 Persistence; Crop damage; Abiotic injuries; Sowing date
 
 
 192                                                    NAL Call. No.: SB249.N6
 Impact of legume cover crops on soilborne plant pathogens of cotton.
 Rothrock, C.S.; Kirkpatrick, T.L.
 Memphis, Tenn. : National Cotton Council of America; 1990.
 Proceedings - Beltwide Cotton Production Research Conferences. p. 30-31; 1990. 
 Meeting held January 9-14, 1990, Las Vegas, Nevada.  Includes references.
 
 Language:  English
 
 Descriptors: Gossypium hirsutum; Cover crops; Fungus control; Rhizoctonia
 solani; Thielaviopsis basicola
 
 
 193                                                  NAL Call. No.: QH84.8.B46
 Impacts of agricultural practices on aquatic oligochaete populations in
 ricefields.
 Simpson, I.C.; Roger, P.A.; Oficial, R.; Grant, I.F.
 Berlin : Springer International; 1993.
 Biology and fertility of soils v. 16 (1): p. 27-33; 1993.  Includes references.
 
 Language:  English
 
 Descriptors: Philippines; Oryza sativa; Rice soils; Azolla; Green manures;
 Nitrogen fertilizers; Sesbania; Tubificidae; Earthworms; Pesticidal action;
 Butachlor; Carbofuran
 
 
 194                                           NAL Call. No.: S599.5.A1A37 1991
 Improved water management of an organic marsh in Burundi.
 Hennebert, P.
 Cairo, Egypt : [Ain Shams University, Faculty of Agriculture]; 1993.
 Second African Soil Science Society Conference on Soil and Water Management for
 Sustainable Productivity : proceedings of the conference at the Egyptian
 International Center for Agriculture, Cairo, Egypt, November 4-10, 1991 /. p.
 397-401; 1993.  Includes references.
 
 Language:  English
 
 Descriptors: Burundi; Cabt; Oryza sativa; Phaseolus; Rotations; Water
 management; Irrigation
 
 
 195                                                   NAL Call. No.: S596.7.D4
 Improving nitrogen-fixing systems and integrating them into sustainable rice
 farming.
 Watanabe, I.; Liu, C.C.
 Dordrecht : Kluwer Academic Publishers; 1992.
 Developments in plant and soil sciences v. 49: p. 57-67; 1992.  In the series
 analytic: Biological nitrogen fixation for sustainable agriculture / edited by
 J.K. Ladha, T. George, and B.B. Bohlool. Extended versions of papers presented
 in the symposium "Role of biological nitrogen fixation in sustainable
 agriculture", 1990, Kyoto, Japan.  Includes references.
 
 Language:  English
 
 Descriptors: Oryza sativa; Nitrogen fixation; Biological production; Nitrogen;
 Sustainability; Soil fertility
 
 Abstract:  This paper summarizes recent achievements in exploiting new
 biological nitrogen fixation (BNF) systems in rice fields, improving their
 management, and integrating them into rice farming systems. The inoculation of
 cyanobacteria has been long recommended, but its effect is erratic and
 unpredictable. Azolla has a long history of use as a green manure, but a number
 of biological constraints limited its use in tropical Asia. To overcome these
 constraints, the Azolla-Anabaena system as well as the growing methods were
 improved. Hybrids between A. microphylla and A. filiculoides (male) produced
 higher annual biomass than either parent. When Anabaena from high temperature-
 tolerant A. microphylla was transferred to Anabaena-free A. filiculoides, A.
 filiculoides became tolerant of high temperature. Azolla can have multiple
 purposes in addition to being a N source. An integrated Azolla-fish-rice system
 developed in Fujian, China, could increase farmers' income, reduce expenses,
 and increase ecological stability. A study using Azolla labeled with N showed
 the reduction of N losses by fish uptake of N. The Azolla mat could also reduce
 losses of urea N by lowering floodwater-pH and storing a part of applied N in
 Azolla. Agronomically useful aquatic legumes have been explored within Sesbania
 and Aeschynomene. S. rostrata can accumulate more than 100 kg N ha-1 in 45 d.
 Its N2 fixation by stem nodules is more tolerant of mineral N than that by root
 nodules, but the flowering of S. rostrata is sensitive to photoperiod. Aquatic
 legumes can be used in rainfed rice fields as N scavengers and N2 fixers. The
 general principle of integrated users of BNF in rice-farming systems is shown.
 
 
 196                                                  NAL Call. No.: 464.9 C16S
 Incidence of root rot organisms, root rot severity, and take-all in winter
 wheat following cereal and legume rotation crops.
 Celetti, M.J.; Johnston, H.W.; Kimpinski, J.
 Ottawa : Research Branch, Agriculture Canada; 1990.
 Canadian plant disease survey v. 70 (1): p. 52-53; 1990.
 
 Language:  English
 
 Descriptors: Prince edward Island; Triticum aestivum; Gibberella avenacea;
 Gibberella pulicaris; Gibberella zeae; Rhizoctonia solani; Rhizoctonia
 cerealis; Root rots; Gaeumannomyces graminis; Fungal diseases; Incidence;
 Rotations; Legumes
 
 
 197                                                  NAL Call. No.: 464.8 P692
 Incidence of soil-borne plant pathogens isolated from barley and winter wheat,
 and other crops in the rotation, on Prince Edward Island.
 Celetti, M.J.; Johnston, H.W.; Kimpinski, J.; Plant, H.W.; Martin, R.A.
 Oxford : Blackwell Scientific Publications; 1990 Dec.
 Plant pathology v. 39 (4): p. 606-611; 1990 Dec.  Includes references.
 
 Language:  English
 
 Descriptors: Prince edward Island; Hordeum vulgare; Triticum aestivum;
 Trifolium hybridum; Trifolium pratense; Glycine max; Rotations; Root rots;
 Crown; Incidence; Disease surveys; Plant pathogenic fungi; Rhizoctonia solani;
 Cochliobolus sativus; Fusarium; Tylenchorhynchus; Plant parasitic nematodes;
 Population density
 
 
 198                                                NAL Call. No.: S494.5.S86S8
 Inclusion of alfalfa (Medicago sativa L.) in crop rotations in the Eastern Corn
 Belt: some environmental and economic implications.
 Foltz, J.C.; Martin, M.A.; Lowenberg-DeBoer, J.
 Binghamton, N.Y. : Food Products Press; 1991.
 Journal of sustainable agriculture v. 2 (2): p. 117-133; 1991.  Includes
 references.
 
 Language:  English
 
 Descriptors: Corn belt states of U.S.A.; Medicago sativa; Zea mays; Glycine
 max; Rotations; Continuous cropping; Economic analysis; Profitability; Soil
 variability; Sustainability; Models
 
 
 199                                                    NAL Call. No.: 23 AU783
 Increasing grain yield and water use of wheat in a rainfed Mediterranean type
 environment.
 Anderson, W.K.
 Melbourne : Commonwealth Scientific and Industrial Research Organization; 1992.
 Australian journal of agricultural research v. 43 (1): p. 1-17; 1992.
 Includes references.
 
 Language:  English
 
 Descriptors: Western australia; Triticum; Crop yield; Cultivars; Dry farming;
 Legumes; Nitrogen fertilizers; Phosphates; Rotations; Sowing date; Sowing
 rates; Water use efficiency; Yield components
 
 
 200                                                 NAL Call. No.: SB317.5.H68
 Increasing sustainability by intercropping.
 Coolman, R.M.; Hoyt, G.D.
 Alexandria, VA : American Society for Horticultural Science, c1991-; 1993 Jul.
 HortTechnology v. 3 (3): p. 309-312; 1993 Jul.  Includes references.
 
 Language:  English
 
 Descriptors: Vegetables; Crop production; Sustainability; Intercropping; Cover
 crops; Relay cropping; Plant competition; Legumes; Nitrogen fixation;
 Interspecific competition; Literature reviews
 
 
 201                                                  NAL Call. No.: QL461.E532
 Influence of cover crops and tillage on seedcorn maggot (Diptera:
 anthomyiidae) populations in soybeans.
 Hammond, R.B.
 Lanham, Md. : Entomological Society of America; 1990 Jun.
 Environmental entomology v. 19 (3): p. 510-514; 1990 Jun.  Includes references.
 
 Language:  English
 
 Descriptors: Glycine max; Medicago sativa; Secale cereale; Zea mays; Cover
 crops; Delia platura; Population density; No-tillage
 
 Abstract:  The effects of cover crops and crop residues on seedcorn maggot,
 Delia platura (Meigen), population dynamics in soybeans (Glycine max Merrill)
 were studied when incorporated into the soil before crop planting and when left
 on the soil surface where soybeans are planted, using no-tillage practices.
 Crop covers and residues had a dramatic effect on seedcorn maggot populations;
 highest numbers were obtained when cover crops were incorporated. When no-
 tillage planting methods were used, no enhancement of populations was obtained.
 Significantly greater numbers of D. platura adults were obtained from plots
 where alfalfa (Medicago sativa L.) was incorporated into the soil, followed by
 rye (Secale cereale (L.)), soybean residue, and least with corn (Zea mays L.)
 residue. Orthogonal comparisons indicated that more seedcorn maggots were
 obtained when a live, green cover was incorporated into the soil than with dead
 crop residue. Orthogonal comparisons also showed that more adults were
 collected when a legume was incorporated compared with a grass.
 
 
 202                                                    NAL Call. No.: 1.9 P69P
 Influence of cropping systems on Macrophomina phaseolina populations in soil.
 Singh, S.K.; Nene, Y.L.; Reddy, M.V.
 St. Paul, Minn. : American Phytopathological Society; 1990 Oct.
 Plant disease v. 74 (10): p. 812-814; 1990 Oct.  Includes references.
 
 Language:  English
 
 Descriptors: Macrophomina phaseolina; Soil fungi; Cropping systems; Rotations;
 Intercropping; Sorghum bicolor; Vigna unguiculata; Carthamus tinctorius; Cicer
 arietinum
 
 
 203                                                    NAL Call. No.: 1.9 P69P
 Influence of pea cropping history on disease severity and yield depression.
 Bodker, L.; Leroul, N.; Smedegaard-Petersen, V.
 St. Paul, Minn., American Phytopathological Society; 1993 Sep.
 Plant Disease v. 77 (9): p. 896-900; 1993 Sep.  Includes references.
 
 Language:  English
 
 Descriptors: Pisum sativum; Plant pathogenic fungi; Root rots; Plant disease
 control; Cultural control; Rotations; Disease resistance; Crop yield; Indexes
 
 
 204                                                  NAL Call. No.: 464.8 P566
 Influence of previous crops and nematicide treatments on root lesion nematode
 populations and crop yields.
 Kimpinski, J.; Edwards, L.M.; Gallant, C.E.; Johnston, H.W.; MacLeod, J.A.;
 Sanderson, J.B.
 Saint-Hyacinthe : Quebec Society for the Protection of Plants; 1992 Apr.
 Phytoprotection v. 73 (1): p. 3-11; 1992 Apr.  Includes references.
 
 Language:  English
 
 Descriptors: Prince edward Island; Hordeum vulgare; Trifolium pratense; Phleum
 pratense; Solanum tuberosum; Plant parasitic nematodes; Pratylenchus penetrans;
 Rotations; Aldicarb; Crop yield
 
 
 205                                                  NAL Call. No.: SB317.5.A6
 Influence of previous summer crop on the response of irrigated wheat to
 nitrogen fertilization.
 Greenfield, P.L.
 Sunnyside : South African Weed Science Society; 1992.
 Applied plant science; Toegepaste plantwetenskap v. 6 (2): p. 60-64; 1992.
 Includes references.
 
 Language:  English
 
 Descriptors: South  Africa; Triticum aestivum; Double cropping; Nitrogen
 fertilizers; Plant nutrition; Rotations; Split dressings; Crop yield; Irrigated
 conditions; Glycine max; Phaseolus vulgaris; Sorghum bicolor; Zea mays
 
 
 206                                                NAL Call. No.: 275.29 IN2ID
 Influence of production practices on yield estimates for corn, soybeans, and
 wheat.
 Doster, D.H.; Parsons, S.D.; Griffith, D.R.; Steinhardt, G.C.; Mengel, D.B.;
 Nielsen, R.L.; Christmas, E.P.
 West Lafayette, Ind. : The Service; 1991 Sep.
 Publication I.D. - Cooperative Extension Service, Purdue University v.): 12 p.;
 1991 Sep.
 
 Language:  English
 
 Descriptors: Indiana; Zea mays; Glycine max; Triticum; Yields; Factors of
 production; Cultivars; Planting date; Row spacing; Rotations; Soil types;
 Statistics
 
 
 207                                                    NAL Call. No.: 1.9 P69P
 Influence of tillage and crop rotation on yield, stalk rot, and recovery of
 Fusarium and Trichoderma spp. from corn.
 Lipps, P.E.; Deep, I.W.
 St. Paul, Minn. : American Phytopathological Society; 1991 Aug.
 Plant disease v. 75 (8): p. 828-833; 1991 Aug.  Includes references.
 
 Language:  English
 
 Descriptors: Ohio; Zea mays; Glycine max; Fusarium; Trichoderma; Strains;
 Isolation; Plant tissues; Stems; Crown; Mesocotyls; Fungal diseases; No-
 tillage; Plowing; Continuous cropping; Rotations; Water stress; Clay loam
 soils; Crop yield; Grain; Plant disorders; Incidence; Rain; Sampling; Temporal
 variation; Autumn; Cultural control
 
 
 208                                                    NAL Call. No.: 79.8 W41
 Influence of tillage, crop rotation, and weed management on giant foxtail
 (Setaria faberi) population dynamics and corn yield.
 Schreiber, M.M.
 Champaign, Ill. : Weed Science Society of America; 1992.
 Weed science v. 40 (4): p. 645-653; 1992.  Paper presented at the "Symposium on
 crop/weed management and the dynamics of weed seedbanks," February 11, 1992,
 Orlando, Florida.  Includes references.
 
 Language:  English
 
 Descriptors: Indiana; Zea mays; Setaria faberi; Weed biology; Seed banks;
 Population density; Population dynamics; Plowing; No-tillage; Rotations;
 Allelopathy; Cropping systems; Crop yield; Weed control; Chemical control;
 Herbicides
 
 Abstract:  A long-term integrated pest management study initiated in 1980 and
 continued through 1991 was conducted to determine interactions of tillage, crop
 rotation, and herbicide use levels on weed seed populations, weed populations,
 and crop yield. This paper presents giant foxtail seed population and stand
 along with corn yield in continuous corn, corn rotated with soybean, or corn
 following wheat in a soybean-wheat-corn rotation. Increasing herbicide use
 levels above the minimum reduced giant foxtail seed in the 0- to 2.5-cm depth
 of soil. Reducing tillage from conventional moldboard plowing to chiseling to
 no-tilling increased giant foxtail seed in only the top 0 to 2.5 cm of soil.
 No-tilling increased giant foxtail seed over conventional tillage in each year
 data were collected. Growing corn in a soybean-corn or soybean-wheat-corn
 rotation reduced giant foxtail seed from corn grown continuously in all three
 soil depths sampled: 0 to 2.5 cm, 2.5 to 10 cm, and 10 to 20 cm. Although
 stands of giant foxtail tended to follow soil weed seed counts, crop rotation
 significantly reduced giant foxtail stand with maximum reduction in the
 soybean-wheat-corn rotation in all tillage systems. Giant foxtail stands were
 reduced following wheat in no-tilling, probably because of the allelopathic
 influence of wheat straw. Corn yields showed weed management levels above
 minimum control are not justified regardless of tillage and crop rotation.
 
 
 209                                                    NAL Call. No.: 79.8 W41
 Influence of tillage on soybean (Glycine max) herbicide carryover to grass and
 legume forage crops in Missouri.
 Walsh, J.D.; DeFelice, M.S.; Sims, B.D.
 Champaign, Ill. : Weed Science Society of America; 1993 Jan.
 Weed science v. 41 (1): p. 144-149; 1993 Jan.  Includes references.
 
 Language:  English
 
 Descriptors: Missouri; Cabt; Fodder crops; Tillage; No-tillage; Herbicides;
 Application rates; Persistence; Biomass production; Herbicide residues; Glycine
 max; Rotations
 
 Abstract:  Studies were established in 1988, 1989, and 1990 at two locations in
 Missouri to study the influence of fall tillage and herbicides on carryover of
 several residual soybean herbicides to grass and legume forage crops.
 Chlorimuron, clomazone, imazaquin, imazethapyr, and metribuzin plus chlorimuron
 were applied at their registered and 2X-registered rates in soybeans. Forage
 crops were planted the following fall and spring after herbicide application
 and evaluated for carryover effects. Fall tillage did not influence the
 carryover potential of these herbicides. However, herbicides injured several of
 the rotational crops. This injury was crop species and herbicide specific.
 
 
 210                                                    NAL Call. No.: 23 AU792
 The influence of tillage, stubble management and crop rotation on the
 persistence of great brome (Bromus diandrus Roth).
 Heenan, D.P.; Taylor, A.C.; Leys, A.R.
 East Melbourne : Commonwealth Scientific and Industrial Research Organization;
 1990.
 Australian journal of experimental agriculture v. 30 (2): p. 227-230; 1990.
 Includes references.
 
 Language:  English
 
 Descriptors: New South Wales; Lupinus; Triticum; Bromus diandrus; Cultural
 control; Prescribed burning; Herbicides; Rotations; Stubble; Tillage; Weed
 control
 
 
 211                                                    NAL Call. No.: 79.8 W41
 Influence of tillage systems on annual weed densities and control in solid-
 seeded soybean (Glycine max).
 Buhler, D.D.; Oplinger, E.S.
 Champaign, Ill. : Weed Science Society of America; 1990 Mar.
 Weed science v. 38 (2): p. 158-165; 1990 Mar.  Includes references.
 
 Language:  English
 
 Descriptors: Wisconsin; Glycine max; Row spacing; Weed control; Chemical
 control; Alachlor; Chloramben; Clomazone; Imazaquin; Metolachlor; Metribuzin;
 Pendimethalin; Application rates; No-tillage; Tillage; Chiselling; Chenopodium
 album; Setaria faberi; Amaranthus retroflexus; Abutilon theophrasti; Population
 dynamics; Crop yield; Seeds; Phytotoxicity; Rotations; Zea mays
 
 Abstract:  Field research was conducted at Arlington, WI, and Janesville, WI,
 in 1986 and 1987 to evaluate the effect of conventional-tillage, chisel plow,
 and no-till systems on the density and control of annual weed species in solid-
 seeded soybean. Common lambsquarters densities were not greatly influenced by
 tillage systems, but redroot pigweed densities were generally highest in the
 chisel plow system. Conventional tillage always had greater velvetleaf
 densities than no-till and no-till always had greater giant foxtail densities
 than conventional tillage. Giant foxtail and redroot pigweed became more
 difficult to control when tillage was reduced, while velvetleaf became less of
 a problem. This response was not observed with all herbicide treatments
 evaluated and several herbicide treatments provided excellent weed control.
 Soybean yield was not affected by tillage systems under weed-free conditions
 and differences in soybean yield appeared to be due to differences in weed
 control.
 
 
 212                                                    NAL Call. No.: SB599.C8
 Influence of weed-control practices in the first crop on the tillage
 requirements for the succeeding crops in an upland rice-maize-cowpea cropping
 sequence.
 Elliot, P.C.; Moody, K.
 Guildford : Butterworths; 1991 Feb.
 Crop protection v. 10 (1): p. 28-33; 1991 Feb.  Includes references.
 
 Language:  English
 
 Descriptors: Philippines; Oryza sativa; Upland rice; Sequential cropping; Zea
 mays; Vigna unguiculata; Weeding; Hoeing; Manual weed control; Chemical
 control; Pendimethalin; No-tillage; Plowing; Harrowing; Crop yield; Grain; Cost
 benefit analysis
 
 
 213                                                    NAL Call. No.: 100 L939
 Integrating red rice control measures in soybean-rice rotations.
 Griffin, J.L.; Dunand, R.T.; Baker, J.B.; Regan, R.P.; Cohn, M.A.
 Baton Rouge, La. : The Station; 1991.
 Louisiana agriculture - Louisiana Agricultural Experiment Station v. 34 (3): p.
 6-7; 1991.
 
 Language:  English
 
 Descriptors: Louisiana; Glycine max; Oryza sativa; Rotations; Oryza rufipogon;
 Weed control
 
 
 214                                                    NAL Call. No.: 79.8 W41
 Interaction of light, soil moisture, and temperature with weed suppression by
 hairy vetch residue.
 Teasdale, J.R.
 Champaign, Ill. : Weed Science Society of America; 1993 Jan.
 Weed science v. 41 (1): p. 46-51; 1993 Jan.  Includes references.
 
 Language:  English
 
 Descriptors: Vicia; Vetch; Cover crops; Light relations; Allelopathy; Soil
 water; Temperature; Shade; Establishment; Zea mays; Abutilon theophrasti;
 Setaria viridis; Chenopodium album; Night temperature; Weed control;
 Suppression
 
 Abstract:  The influence of light, soil moisture. and temperature on
 establishment of selected species through hairy vetch residue on the soil
 surface was investigated under controlled conditions in the greenhouse. Hairy
 vetch residue at rates ranging from 0 to 616 g m-2 had no effect on corn,
 slightly reduced velvetleaf and green foxtail establishment, and severely
 inhibited common lambsquarters establishment under full sunlight conditions.
 The same rates of hairy vetch residue reduced velvetleaf, green foxtail, and
 common lambsquarters establishment more under a shade cloth with 9% light
 transmittance than under full sunlight. Day/night temperatures of 24/16 or
 32/26 degrees C had no effect and soil moistures of 50 or 133% field capacity
 had little effect on response of all species to residue rates. Weed
 establishment was similar under shade cloth without residue as under residue
 with an equivalent light transmittance, suggesting that light was more
 important than allelopathy or physical impedance for weed suppression by hairy
 vetch residue.
 
 
 215                                                  NAL Call. No.: S539.5.J68
 Interseeded forage legume potential as winter ground cover, nitrogen source,
 and competitor.
 Exner, D.N.; Cruse, R.M.
 Madison, WI : American Society of Agronomy, c1987-; 1993 Apr.
 Journal of production agriculture v. 6 (2): p. 226-231; 1993 Apr.  Includes
 references.
 
 Language:  English
 
 Descriptors: Zea mays; Medicago sativa; Melilotus officinalis; Trifolium
 pratense; Trifolium hybridum; Interplanting; Forage; Ground cover; Crop weed
 competition; Plant competition; Rowcrops; Rain; Seasonal variation; Soil water;
 Crop yield; Crop density; Sowing date; Crop establishment; Seed mixtures; Row
 orientation; Light intensity; Eptc; Weeds; Weeding
 
 
 216                                                     NAL Call. No.: 4 AM34P
 Irrigation method and water quality effects on corn yield in the mid-Atlantic
 coastal plain.
 Adamsen, F.J.
 Madison, Wis. : American Society of Agronomy; 1992 Sep.
 Journal of the American Society of Agronomy v. 84 (5): p. 837-843; 1992 Sep.
 Includes references.
 
 Language:  English
 
 Descriptors: Virginia; Zea mays; Crop yield; Sprinkler irrigation; Trickle
 irrigation; Irrigation water; Water quality; Coastal plains; Loam soils; Sandy
 soils; Soil ph; Rain; Distribution; Sodic water; Sodium; Calcium; Salts in soil
 
 Abstract:  Deep well sodic sources of irrigation water are often more readily
 available than high quality shallow or surface sources for corn (Zea mays L.)
 grown in the U.S. Southeast. The objective of this study was to determine the
 effect of irrigation water quality and irrigation method on corn production in
 the Virginia-North Carolina coastal plain. Pioneer 3320 corn was grown in
 rotation with peanut (Arachis hypogaea L.) on a Kenansville loamy sand (loamy,
 siliceous, thermic Arenic Hapludult) in Suffolk, VA, in 1984, 1985, 1986, and
 1988. Corn was irrigated with either overhead sprinklers or trickle lines
 buried 0.35 to 0.41 m below each row with sodic deep well (142 m) and non-sodic
 shallow (10 m) water. Sodic water had 220 mg Na L-1, a pH of 8.5, and a sodium
 adsorption ratio (SAR) of 103. Non-sodic water had 4.8 mg Na L-1, a pH of 4.8,
 and an SAR of 3.1. Corn yields averaged 9970 kg ha-1 with irrigation and 7650
 kg ha-1 without. Irrigation method and water quality did not affect yields of
 irrigated corn. Soil pH increased during the study but appeared to stabilize
 between 6 and 7 in the surface soil. No evidence of an increase in subsoil
 acidity was detected. Winter rainfall and gypsum applied to the rotational
 peanut crop appear to be adequate to prevent the soil exchange from being
 dominated by Na. The results indicate that sodic water can be used to irrigate
 corn in the mid-Atlantic coastal plain and that trickle irrigation can reduce
 water input for corn by 30% or more.
 
 
 217                                                      NAL Call. No.: HD1.A3
 ISFARM--an integrated system for farm management: applicability.
 Amir, I.; Puech, J.; Granier, J.
 Essex : Elsevier Applied Science Publishers; 1993.
 Agricultural systems v. 41 (1): p. 23-39; 1993.  Includes references.
 
 Language:  English
 
 Descriptors: Midi pyrenees; Maize; Soybeans; Winter wheat; Rotations; Farm
 planning; Farm management; Decision making; Simulation models; Linear
 programming; Expert systems; Methodology; Comparisons; Value theory; Irrigation
 requirements; Evaluation; Production costs
 
 
 218                                                     NAL Call. No.: 4 AM34P
 Legume cover crops as a nitrogen source for no-till corn and grain sorghum.
 Blevins, R.L.; Herbek, J.H.; Frye, W.W.
 Madison, Wis. : American Society of Agronomy; 1990 Jul.
 Agronomy journal v. 82 (4): p. 769-772; 1990 Jul.  Includes references.
 
 Language:  English
 
 Descriptors: Kentucky; Zea mays; Sorghum bicolor; No-tillage; Vicia villosa;
 Vicia; Secale cereale; Cover crops; Nitrogen fertilizers; Dry matter
 accumulation; Crop yield; Grain; Nutrient removal by plants; Nitrogen content
 
 Abstract:  Increasing use of conservation tillage has brought about a renewed
 interest in growing winter legume cover crops. Field experiments were conducted
 to determine the fertilizer N equivalency of hairy vetch (Vicia villosa Roth),
 big flower vetch (Vicia grandiflora W. Koch var. Kitailbeliana), and rye
 (Secale cereale L.) to no-tillage corn (Zea mays L.) and grain sorghum [Sorghum
 bicolor (L.) Moench]. A fallow treatment, consisting of stalk residue only, was
 used as a comparison. Fertilizer N rates for corn were 0, 50, or 100 kg N ha-1
 for 1980 to 1983 and 0, 85, or 170 kg N ha-1 for 1984 to 1987. Hairy vetch
 produced the most cover crop dry matter with the highest percentage of N.
 During 1980 to 1983, corn grain yields were significantly higher with the vetch
 treatments than with rye or fallow treatments at the 0 and 50 kg N ha-1 rates
 with a tendency toward higher yields at the 100 kg N ha-1 rate. During 1984 to
 1987, corn yields from the vetch treatments were significantly higher than the
 other cover treatments at all N levels. Grain sorghum, like corn yields, were
 greater with the vetch treatments than with the rye or fallow treatments,
 although the bigflower vetch treatment was not significantly higher than the
 fallow treatment at the 170 kg N ha-1 rate. The estimated fertilizer-N
 equivalency of the hairy vetch-N in the corn experiment was 75 kg N ha-1 and
 bigflower vetch was 65 kg N ha-1. Fertilizer N equivalency values in the grain
 sorghum experiment were estimated to be 125 kg N ha-1 for hairy vetch and 135
 kg N ha-1 for bigflower vetch.
 
 
 219                                     NAL Call. No.: S599.9.T783T76 no.90-01
 Legume green manures principles for management based on recent research.
 Lathwell, D. J.
 Soil Management Collaborative Research Support Program
 Raleigh, NC : Soil Management Collaborative Research Support Program, N.C.
 State University,; 1990.
 30 p. : ill. ; 28 cm. (TropSoils bulletin ; no. 90-01).  Includes
 bibliographical references (p. 29-30).
 
 Language:  English
 
 Descriptors: Legumes; Green manure crops; Organic fertilizers
 
 
 220                                               NAL Call. No.: S661.J46 1993
 Legume green manuring.
 Jensen, Tom; Jans, Desiree
 Alberta, Alberta Agriculture
 Edmonton, Alta. : Agriculture Canada, Alberta Agriculture,; 1993.
 7 p. : ill. ; 28 cm.  Cover title.  "Prepared by: Tom Jensen and Desiree
 Jans"--P. 7.  "Funding provided by the Canada-Alberta Environmentally
 Sustainable Agriculture Agreement (CAESA)"--P. 7.  "1993 03 5M"--T.p. verso.
 Agdex 123/20-2.
 
 Language:  English
 
 Descriptors: Green manuring; Green manure crops; Legumes; Organic fertilizers
 
 
 221                                                    NAL Call. No.: 56.9 SO3
 Legume mulch and nitrogen fertilizer effects on soil water and corn production.
 Corak, S.J.; Frye, W.W.; Smith, M.S.
 Madison, Wis. : The Society; 1991 Sep.
 Soil Science Society of America journal v. 55 (5): p. 1395-1400; 1991 Sep.
 Includes references.
 
 Language:  English
 
 Descriptors: Kentucky; Vicia villosa; Zea mays; No-tillage; Crop production;
 Silt loam soils; Cover crops; Live mulches; Crop residues; Preplanting
 treatment; Nitrogen fertilizers; Nitrogen; Nutrient content; Soil water
 content; Temporal variation; Spatial variation; Crop yield; Growth; Nutrient
 transport; Water use efficiency; Crop growth stage; Nutrient availability;
 Water conservation; Profiles; Maize stover; Grain; Precipitation; Transpiration
 
 Abstract:  Hairy vetch (Vicia villosa Roth) as a winter annual legume cover
 crop, can increase grain yield of no-till corn (Zea mays L.). Optimizing
 management of this system depends on understanding beneficial effects. This
 field study examined effects of hairy vetch (HV) and N fertilizer on soil water
 content, crop growth, N assimilation, and water-use efficiency. Cover-crop
 treatments, each with 0 and 255 kg ha-1 of fertilizer N, were (i) winter
 fallow, (ii) aboveground HV removed at corn planting, (iii) HV left in place,
 and (iv) HV left in place and supplemented with that removed from (ii).
 Transpiration by HV before corn planting reduced soil water content, decreasing
 early growth of corn during years of low spring rainfall. By 2 to 4 wk after
 planting, however, soil water content under HV mulch was similar to winter
 fallow. Soil water content was higher with HV mulch only during the second 4-wk
 period following planting and only in the upper 7.5 cm of the profile. Greater
 soil water use associated with N fertilizer occurred after about 8 wk in 2 of
 the 3 yr. Hairy vetch treatments sit the zero-N fertilizer level increased corn
 growth, N assimilation, grain yield, and water-use efficiency. The high-N
 treatment negated these benefits of HV. Because of this and the lack of mulch
 effects on soil water during inter stages of crop growth, we concluded that N
 supplied to no-till corn was the principal, immediate benefit of HV during this
 study.
 
 
 222                                                 NAL Call. No.: S592.7.A1S6
 Legume residue and soil water effects on denitrification in soils of different
 textures.
 Aulakh, M.S.; Doran, J.W.; Walters, D.T.; Power, J.F.
 Exeter : Pergamon Press; 1991.
 Soil biology and biochemistry v. 23 (12): p. 1161-1167; 1991.  Includes
 references.
 
 Language:  English
 
 Descriptors: U.S.A.; India; Vicia villosa; Clay soils; Silt loam soils; Sandy
 loam soils; Soil texture; Cover crops; Crop residues; Incorporation;
 Denitrification; Losses from soil systems; Nitrogen; Soil pore system; Soil
 water content; Porosity; Water holding capacity; Bulk density; Soil air;
 Nutrient availability; Carbon; Biological activity in soil; Soil organic
 matter; Saturated conditions; Nitrate; Overwintering
 
 Abstract:  Legume cover crops commonly used to supply additional N and reduce
 potential for over-winter N leaching losses may also influence denitrification
 depending upon soil water status and soil type. Interrelationships between
 incorporated hairy vetch (Vicia villosa) residue and soil water status on
 denitrification in coarse, medium and fine textured soils were investigated in
 the laboratory. Repacked soil cores were incubated, 10, 20 and 30 d with and
 without acetylene (C2H2). Denitrification losses were 20-200 micrograms N kg-1
 from each soil when 60% of the soil pore space was filled with water and
 increased to from 14.0 to 18.6 mg N kg-1 at 90% water-filled-pore space (WFPS).
 Incorporation of vetch residue (2.5 g kg-1) greatly stimulated denitrification
 (51.1-99.5 mg N kg-1), probably due to greater availability of organic C as
 indicated by higher CO2 emissions. The major denitrification losses occurred
 during the first 10 days and more so in residue-amended soils. The supply of C
 from incorporated legume crop residue was a major factor influencing
 denitrification especially when soil wetness restricted aeration and adequate
 nitrate was present. At similar water contents, rates of denitrification
 differed greatly in soils of varying texture, but when varying water holding
 capacity and bulk density were accounted for using WFPS, all soils behaved very
 similarly. Use of WFPS as an index of aeration status enabled identification
 that differences in denitrification losses in vetch-amended soils of varying
 texture resulted in part from varying capacity to supply NO3(-) and metabolize
 organic matter. These results illustrate the utility of WFPS, compared with
 soil water content, and its reliability as an indicator of reduced aeration
 dependent denitrification for soils of varying texture.
 
 
 223                                                      NAL Call. No.: SB1.H6
 Legumes alone and in combination with manure as fertilizers in an intensive
 muskmelon production system.
 Singogo, W.; Lamont, W.J. Jr; Marr, C.W.
 Alexandria, Va. : American Society for Horticultural Science; 1991 Nov.
 HortScience v. 26 (11): p. 1431; 1991 Nov.  Includes references.
 
 Language:  English
 
 Descriptors: Cucumis melo; Green manures; Medicago sativa; Vicia villosa; Pisum
 sativum; Cattle manure; Trickle irrigation; Plastic film; Intensive production;
 Crop yield; Fruits
 
 
 224                                                     NAL Call. No.: 4 AM34P
 Light transmittance, soil temperature, and soil moisture under residue of hairy
 vetch and rye.
 Teasdale, J.R.; Mohler, C.L.
 Madison, Wis. : American Society of Agronomy, [1949-; 1993 May.
 Agronomy journal v. 85 (3): p. 673-680; 1993 May.  Includes references.
 
 Language:  English
 
 Descriptors: Maryland; Cabt; New York; Cabt; Secale cereale; Vicia villosa;
 Cover crops; Crop residues; Biomass; Microenvironments; Weeds; Seed banks; Seed
 germination; Soil temperature; Light penetration; Soil water content; Cultural
 weed control
 
 Abstract:  Cover crop residue on the surface of soils in no-tillage systems can
 suppress weed emergence and growth. Although allelopathy often is invoked to
 explain weed suppression by residue, physical alterations of the seed
 environment could be important as well. This experiment was conducted to
 determine the light, temperature, and moisture conditions under cover crop
 residue. Hairy vetch (Vicia villosa Roth) and rye (Secale cereale L.) were
 desiccated with a contact herbicide and residue rates ranging from one-fourth
 to four times the natural residue biomass were established in experiments at
 Beltsville, MD and Ithaca, N.Y. Photosynthetic photon flux density (PPFD) was
 determined above and below residue at approximately monthly intervals after
 initiation of the experiment. Transmittance of PPFD through residue declined
 according to an exponential decay function of residue biomass. Transmittance
 was similar through hairy vetch and rye residue initially, but as the
 experiment progressed, transmittance through hairy vetch residue was greater
 than that through rye because of faster decomposition of hairy vetch residue.
 Spectral analysis from 400 to 1100 nm showed a slight increase in transmittance
 as wavelength increased resulting in a slight lowering of the red (660 nm) to
 far-red (730 nm) ratio relative to that of unobstructed sunlight. Soil maximum
 temperature and daily soil temperature amplitude were reduced by cover crop
 residue. Residue prevented the decline of soil water content during droughty
 periods. Results indicated that reductions in light transmittance and daily
 soil temperature amplitude by cover crop residue were sufficient to reduce
 emergence of weeds but that maintenance of soil moisture could increase weed
 emergence.
 
 
 225                                                    NAL Call. No.: 56.8 SO3
 Long-term effects of rate and frequency of applied P on crop yields, plant
 available P, and recovery of fertilizer P in a peanut-wheat rotation.
 Aulakh, M.S.; Pasricha, N.S.; Baddesa, H.S.; Bahl, G.S.
 Baltimore, Md. : Williams & Wilkins; 1991 Apr.
 Soil science v. 151 (4): p. 317-322; 1991 Apr.  Includes references.
 
 Language:  English
 
 Descriptors: Indian punjab; Arachis hypogaea; Triticum aestivum; Phosphorus
 fertilizers; Yield response functions; Nutrient uptake; Recovery; Irrigated
 soils; Application rates; Sandy loam soils
 
 
 226                                                    NAL Call. No.: 56.9 SO3
 Macroporosity of a well-drained soil under no-till and conventional tillage.
 Dunn, G.H.; Phillips, R.E.
 Madison, Wis. : The Society; 1991 May.
 Soil Science Society of America journal v. 55 (3): p. 817-822; 1991 May.
 Includes references.
 
 Language:  English
 
 Descriptors: Kentucky; Hydraulic conductivity; Macropores; No-tillage; Silt
 loam soils; Tillage; Cover crops; Secale cereale; Vicia villosa; Zea mays
 
 Abstract:  Conventional tillage and no-tillage have been shown to affect the
 hydraulic properties of soil. For this reason, a field experiment was conducted
 in 1987 and 1988 to determine the effect of tillage practice and cover crop on
 the macroporosity of a Maury silt loam (fine, mixed, mesic Typic Paleudalf).
 The field used for this study has been in continuous no-till and conventional-
 till corn (Zea mays L.) since 1970. Ponded steady-state infiltration
 measurements were made using double-ring infiltrometers; afterwards, a tension
 infiltrometer was used to measure water flux at -0.4, -0.9, and -1.4 kPa water
 pressure. These negative water pressures were used to calculate equivalent
 cylindrical pore diameters from the capillary-rise equation. Flux at a pressure
 of -0.06 kPa was determined from regression equations for each plot. Equivalent
 pore diameters of 5.0, 0.75, 0.33, and 0.21 mm correspond to -0.06, -0.4, -0.9,
 and -1.4 kPa, respectively. In June 1987, conventional tillage had
 significantly higher water flux than no-till for the 5.0- to 0.75-mm
 equivalent-diameter pore size range. In 1987, rye (Secale cereale L.) cover
 crop plots had significantly higher water-flux values than hairy vetch (Vicia
 villosa Roth.) plots for the same range of equivalent pore sizes. In June 1988,
 no-till plots had significantly higher water-flux values for all equivalent
 pore size ranges. In 1987, 73 and 80% of the total water flux at -0.06 kPa
 water pressure was transmitted through pores > 0.21-mm equivalent diameter in
 no-till and conventional-tillage plots, respectively. The corresponding values
 in 1988 were 83 and 73%.
 
 
 227                                         NAL Call. No.: NBULD3656 1991 O593
 Maize-soybean rotation residue interaction on grain yield..  University of
 Nebraska--Lincoln thesis : Agronomy
 Onyango, Ruth M. Adhiambo
 1991; 1991.
 xi, 70 leaves : ill. ; 28 cm.  Includes bibliographical references.
 
 Language:  English
 
 
 228                                                  NAL Call. No.: S542.A8A34
 Management of bacterial wilt of groundnut using genetic resistance and cultural
 practices.
 Mehan, V.K.; Nigam, S.N.; McDonald, D.
 Canberra, A.C.T. : Australian Centre for International Agricultural Research,
 1985-; 1993.
 ACIAR proceedings (45): p. 211-218; 1993.  In the series analytic: Bacterial
 wilt / edited by G.L. Hartman and A.C. Hayward.  Meeting held on October 28-31,
 1992, Kaohsiung, Taiwan.  Includes references.
 
 Language:  English
 
 Descriptors: Indonesia; Cabt; China; Cabt; Arachis hypogaea; Pseudomonas
 solanacearum; Wilts; Plant disease control; Rotations; Genetic resistance;
 Disease resistance; Cultivars; Intercropping
 
 
 229                                                 NAL Call. No.: QL391.N4J62
 Management of Heterodera glycines by cropping and cultural practices.
 Schmitt, D.P.
 Lake Alfred, Fla. : Society of Nematologists; 1991 Jul.
 Journal of nematology v. 23 (3): p. 348-352; 1991 Jul.  Literature review.
 Includes references.
 
 Language:  English
 
 Descriptors: Glycine max; Heterodera glycines; Nematode control; Rotation;
 Cropping systems; Literature reviews
 
 Abstract:  Heterodera glycines was identified in North Carolina in 1954,
 although symptoms of the disease were noted in the state at least 8 years
 earlier. Crop rotation experiments designed to develop management systems were
 initiated in 1956. Two or more years in production of a nonhost crop resulted
 in decreases of the nematode to low or undetectable levels with acceptable
 subsequent yields of soybean (Glycine max). Because of almost complete
 dependence on resistant cultivars and (or) nematicides for nematode control,
 crop rotation experiments were not conducted from 1962 to 1980. Research on
 control of H. glycines, beginning in 1981, emphasized biological and ecological
 aspects of the nematode in order to determine cropping systems that restrict
 the nematode to nondamaging levels. Mortality during embryogenesis was high at
 temperatures above 30 C. Hatching of eggs occurs readily in May and June.
 Postinfection development takes 2-3 weeks at weekly mean temperatures of 22-29
 C and is slow above and below those temperatures. Egg production is high during
 the late growing season. Some cultural practices such as planting early
 maturing cultivars in mid-to-late June and rotation with a nonhost effectively
 keeps populations at low levels.
 
 
 230                                                   NAL Call. No.: S596.7.D4
 The management of soil acidity for sustainable crop production.
 Edwards, D.G.; Sharifuddin, H.A.H.; Yusoff, M.N.M.; Grundon, N.J.; Shamshuddin,
 J.; Norhayati, M.
 Dordrecht : Kluwer Academic Publishers; 1991.
 Developments in plant and soil sciences v. 45: p. 383-396; 1991.  In the series
 analytic: Plant-Soil Interactions at Low pH / edited by R.J. Wright, V.C.
 Baligar and R.P. Murrmann. Proceedings of the Second International Symposium,
 June 24-29, 1990, Beckley, West Virginia.  Includes references.
 
 Language:  English
 
 Descriptors: Malaysia; Acid soils; Soil management; Ultisols; Oxisols; Tropical
 soils; Plant nutrition; Lime; Aluminum; Magnesium; Calcium; Cropping systems;
 Economic analysis; Hevea; Zea mays; Arachis hypogaea
 
 Abstract:  The Australian Centre for International Agricultural Research
 (ACIAR) has funded a 4-year project to develop sustainable food crop production
 systems on acid, low fertility soils. Field trials were commenced in mid-1986
 at four sites in Malaysia to evaluate crop responses to amelioration of acidity
 in three Ultisols and one Oxisol, and to relate these responses to both solid
 and solution phase soil chemistry. Ground magnesium limestone (GML) (21% Ca,
 12% Mg) was applied at rates up to 8 t per ha-1. The UPM trials involved
 rotation cropping of groundnut and sweet corn, with two crops per year. The
 RRIM trials involved these two crops and grain corn, intercropped with young
 rubber trees for 2 to 3 years before canopy closure. Liming gave strong
 responses in crop yield. Initial applications of 4 and 8 t per ha-1 were
 effective after 3 years in the UPM trials. Yield responses of all crops
 occurred up to the maximal rate of 2 t per ha-1 in the RRIM trials. Rubber tree
 growth benefitted from the intercropping and earlier commercial tapping has
 occurred. Application of GML to groundnut and sweet corn was economically
 viable, while earlier rubber tapping has further economic benefits.
 
 
 231                                                     NAL Call. No.: 23 W52J
 Managing brome grass in the wheat:lupin rotation.
 Cheam, A.H.; Gill, G.; Zaicou, C.
 South Perth : Department of Agriculture, Western Australia; 1992.
 Journal of agriculture v. 33 (3): p. 95-99; 1992.
 
 Language:  English
 
 Descriptors: Western australia; Triticum; Lupinus; Rotations; Weed control;
 Bromus diandrus; Bromus rigidus; Integrated control; Sandy soils
 
 
 232                                                   NAL Call. No.: 56.9 So32
 Managing plant-parasitic nematodes in crop sequences.
 McSorley, R.; Gallaher, R.N.
 S.l. : The Society; 1992.
 Proceedings / v. 51: p. 42-45; 1992.  Meeting held Sept 25-27, 1991, Orlando,
 Florida.  Includes references.
 
 Language:  English
 
 Descriptors: Florida; Cabt; Meloidogyne incognita; Glycine max; Rotations;
 Trifolium incarnatum; Secale cereale; Zea mays; Sorghum bicolor; Sorghum
 sudanense; Nematode control
 
 
 233                                                  NAL Call. No.: S605.5.A43
 Managing white clover living mulch for sweet corn production with partial
 rototilling.
 Grubinger, V.P.; Minotti, P.L.
 Greenbelt, Md. : Institute for Alternative Agriculture; 1990.
 American journal of alternative agriculture v. 5 (1): p. 4-5; 1990.  Includes
 references.
 
 Language:  English
 
 Descriptors: Trifolium repens; Zea mays; Mulches; Nitrogen fertilizers; Green
 manures; Intercropping; Cover crops; Erosion; Rotation; Tillage
 
 
 234                                                  NAL Call. No.: S605.5.A43
 Mandatory supply controls versus flexibility policy options for encouraging
 sustainable farming systems.
 Dobbs, T.L.; Becker, D.L.
 Greenbelt, Md. : Institute for Alternative Agriculture; 1992.
 American journal of alternative agriculture v. 7 (3): p. 122-128; 1992.
 Includes references.
 
 Language:  English
 
 Descriptors: South Dakota; Agricultural policy; Sustainability; Alternative
 farming; Rotations; Program evaluation; Crop yield; Cost benefit analysis;
 Federal programs
 
 Abstract:  We analyzed two sets of farm policy options, representing different
 ideological approaches to government involvement in agriculture, to estimate
 their effects on the relative economic attractiveness of "sustainable" and
 "conventional" farming systems. The mandatory supply control approach, through
 strict acreage limitations on program crops, represents a strong government
 role in commodity supply management. The Normal Crop Acreage approach on the
 other hand, allows farmers greater flexibility in deciding what crops to grow.
 We used economic models of five pairs of case study farms in different
 agroclimatic areas of South Dakota, covering corn-soybean, spring wheat, and
 winter wheat growing regions. Mandatory restrictions on the planted acreage of
 "program" crops, including soybeans, were found to favor the conventional
 systems, because they induced high prices for crops that predominate in
 conventional systems, especially corn, soybeans, and wheat. In principle,
 however, mandatory acreage controls could require compliance with certain
 sustainable agriculture practices. Normal Crop Acreage (NCA) proposals can
 encourage greater use of sustainable farming systems. Where conventional corn
 and soybean production is relatively profitable, as in parts of eastern South
 Dakota, NCA options by themselves appear insufficient to induce change overs to
 sustainable cropping systems. In wheat growing areas of northern and western
 South Dakota, however, where the two systems often are about equally
 profitable, NCA policies could promote sustainable systems, particularly if
 deficiency payments are not reduced for harvesting legumes and other non-
 program crops on NCA base. To have this positive effect, NCA policies must be
 introduced gradually and structured to limit adverse effects on the markets for
 legumes and other non-program crops that are important in sustainable
 rotations.
 
 
 235                                                 NAL Call. No.: 290.9 AM32T
 Mass of crop residue and its relationship with soil cover for a corn, dry bean,
 and sugarbeet rotation.
 Smith, J.A.; Yonts, C.D.; Rath, M.D.; Bailie, J.E.
 St. Joseph, Mich. : American Society of Agricultural Engineers; 1990 Sep.
 Transactions of the ASAE v. 33 (5): p. 1503-1508; 1990 Sep.  Includes
 references.
 
 Language:  English
 
 Descriptors: Beta vulgaris; Dry beans; Zea mays; Crop residues; Biomass
 production; Cover crops; Rotations; Tillage
 
 Abstract:  The mass and percent cover of crop residue on the soil surface were
 measured for three tillage systems in a crop rotation of corn, dry edible
 beans, and sugarbeets under furrow irrigation. The tillage systems included a
 moldboard plow-based system, a rotary strip till system, and a system which
 utilized minimum tillage prior to planting. A good relationship was found
 between mass and soil cover when corn residue predominated, but not when dry
 edible bean or sugarbeet residues were the dominate residues. The reduced
 tillage systems retained greater residue mass on the soil surface than the
 moldboard plow system for almost two years of the three year crop rotation. The
 mass of surface residue for all three tillage systems was less than 0.5 t/ha
 for a period of one year following sugarbeet harvest. The variability of the
 residue mass measurement was reduced when the residue was washed.
 
 
 236                                                 NAL Call. No.: QL391.N4J62
 Maximizing the potential of cropping systems for nematode management.
 Noe, J.P.; Sasser, J.N.; Imbriani, J.L.
 Lake Alfred, Fla. : Society of Nematologists; 1991 Jul.
 Journal of nematology v. 23 (3): p. 353-361; 1991 Jul.  Includes references.
 
 Language:  English
 
 Descriptors: Gossypium hirsutum; Glycine max; Hoplolaimus columbus; Nematode
 control; Rotation; Cropping systems; Population density; Yield losses
 
 Abstract:  Quantitative techniques were used to analyze and determine optimal
 potential profitability of 3-year rotations of cotton, Gossypium hirsutum cv.
 Coker 315, and soybean, Glycine max cv. Centennial, with increasing population
 densities of Hoplolaimus columbus. Data collected from naturally infested on-
 farm research plots were combined with economic information to construct a
 microcomputer spreadsheet analysis of the cropping system. Nonlinear
 mathematical functions were fitted to field data to represent damage functions
 and population dynamic curves. Maximum yield losses due to H. columbus were
 estimated to be 20 on cotton and 42% on soybean. Maximum at harvest population
 densities were calculated to be 182/100 cm3 soil for cotton and 149/100 cm3
 soil for soybean. Projected net incomes ranged from a $17.74/ha net loss for
 the soybean-cotton-soybean sequence to a net profit of $46.80/ha for the
 cotton-soybean-cotton sequence. The relative profitability of various rotations
 changed as nematode densities increased, indicating economic thresholds for
 recommending alternative crop sequences. The utility and power of quantitative
 optimization was demonstrated for comparisons of rotations under different
 economic assumptions and with other management alternatives.
 
 
 237                                                  NAL Call. No.: S605.5.A43
 Mechanical and cultural weed control in corn and soybeans.
 Gunsolus, J.L.
 Greenbelt, Md. : Institute for Alternative Agriculture; 1990.
 American journal of alternative agriculture v. 5 (3): p. 114-119; 1990.
 Includes references.
 
 Language:  English
 
 Descriptors: Minnesota; Zea mays; Glycine max; Weeds; Cultural weed control;
 Mechanical methods; Planting date; Row spacing; Rotations; Nitrogen
 fertilizers; Application date; Hoeing; Rotary hoes; Interrow cultivation;
 Temporal variation; Crop losses; Yield losses; Crop weed competition; Seed
 germination; Soil depth
 
 Abstract:  Many farmers and consumers are reevaluating chemical weed control
 because of the environmental risks of herbicides and their influence on farm
 size and diversity. This paper reviews research of the last 35 years on
 mechanical and cultural weed control in corn (Zea mays L.) and soybeans
 (Glycine max L.). Soybeans can better use the weed control advantages of late
 planting and narrow row spacing and are less affected by early stand losses
 from mechanical weed control In Minnesota, delaying planting to early June
 allows early germinating weeds to be controlled by preplant tillage but reduces
 the maximum yield potential of corn by approximately 25 percent and soybeans by
 approximately 1O percent. Narrow rows allow the crop canopy to close earlier,
 preventing emerging weeds from developing. However, in a nonchemical weed
 control system, the row spacing should allow for inter-row cultivation to
 control weeds that emerge with the crop. Up to a 10 percent reduction in crop
 stand may be expected in fields that have been rotary hoed In Minnesota, a 10
 percent stand loss results in a 2 percent loss of corn yield potential and no
 loss of soybean yield potential. Successful mechanical weed control is directly
 related to the timeliness of the operation. Rotary hoeing is effective on weeds
 that have germinated but not yet emerged but not on weeds that germinate from
 deeper than 5 cm, on no-till fields, or on fields with more than 20 to 30
 percent crop residue. Inter-row cultivation is most effective on weeds up to 10
 to 15 cm tall. Successful nonchemical weed control requires highly refined
 management skills and is as much an art as a science.
 
 
 238                                                   NAL Call. No.: 56.8 C162
 Microbial and biochemcial changes induced by rotation and tillage in a soil
 under barley production.
 Angers, D.A.; Bissonnette, N.; Legere, A.; Samson, N.
 Ottawa : Agricultural Institute of Canada, 1957-; 1993 Feb.
 Canadian journal of soil science v. 73 (1): p. 39-50; 1993 Feb.  Includes
 references.
 
 Language:  English
 
 Descriptors: Quebec; Cabt; Hordeum vulgare; Trifolium pratense; Rotations;
 Plowing; Chiselling; Conservation tillage; Comparisons; No-tillage; Soil
 organic matter; Carbon; Soil flora; Biomass; Carbohydrates; Alkaline
 phosphatase; Soil enzymes; Enzyme activity; Temporal variation; Soil
 management; Biological activity in soil; Quality
 
 
 239                                                    NAL Call. No.: 56.9 SO3
 Mineralization of nitrogen from nitrogen-15 labeled crop residues and
 utilization by rice.
 Norman, R.J.; Gilmour, J.T.; Wells, B.R.
 Madison, Wis. : The Society; 1990 Sep.
 Soil Science Society of America journal v. 54 (5): p. 1351-1356; 1990 Sep.
 Includes references.
 
 Language:  English
 
 Descriptors: Triticum aestivum; Oryza sativa; Glycine max; Crop residues;
 Nitrogen; Fertilizers; Labeling; Mineralization; Uptake; Rotation; Utilization
 
 Abstract:  The availability of N from the residues of the previous crop to the
 subsequent rice (Oryza sativa L.) crop is largely unknown. The objectives of
 this study were to (i) measure the mineralization of N from 15N-labeled rice,
 soybean (Glycine max L.), and wheat (Triticum aestivum L.) residues and the
 uptake by a subsequent rice crop; and (ii) compare the 15N tracer method with
 the standard fertilizer-N response method used in field studies to quantify the
 N contribution from the crop residue to the next crop. Nitrogen mineralization
 from decomposing crop residues was measured by soil sampling prior to seeding
 the rice crop and after seeding by plant sampling the rice at maturity. The
 minimum estimate of the amount of residue N mineralized from the time of
 residue incorporation until rice harvest was 9, 52, and 38% of the rice,
 soybean, and wheat residue N, respectively. The amount of residue N recovered
 in the rice crop was 3, 11, and 37% of the rice, soybean, and wheat residue N,
 respectively. The lower the C/N ratio and the higher the amount of N in the
 residue, the lower was the amount of residue N recovered in the soil organic
 fraction at harvest and the higher was the amount of residue N mineralized. The
 15N tracer method compared favorably with the fertilizer N response method when
 the uptake efficiency of the fertilizer N was taken into account.
 
 
 240                                                   NAL Call. No.: SB193.P72
 Multicut berseem clover as a double crop for Eastern Oregon.
 Saunders, L.; Shock, C.; Stieber, T.
 Madison, Wis. : The Department; 1990.
 Progress report, clovers and special purpose legumes research - University of
 Wisconsin, Department of Agronomy v. 23: p. 34; 1990.
 
 Language:  English
 
 Descriptors: Oregon; Trifolium alexandrinum; Double cropping; Clover hay; Green
 manures
 
 
 241                                                  NAL Call. No.: QH84.8.B46
 N2 fixation in two Sesbania species and its transfer to rice (Oryza sativa L.)
 as revealed by 15N technology.
 Seneviratne, G.; Kulasooriya, S.A.; Weerakoon, W.L.; Rosswall, T.
 Berlin : Springer International; 1992.
 Biology and fertility of soils v. 14 (1): p. 37-42; 1992.  Includes references.
 
 Language:  English
 
 Descriptors: Sri lanka; Sesbania; Nitrogen fixation; Nitrogen; Isotope
 labeling; Green manures; Oryza sativa; Soil fertility; Crop yield; Flooded rice
 
 
 242                                                 NAL Call. No.: QL391.N4J62
 Nematode densities associated with corn and sorghum cropping systems in
 Florida.
 Gallaher, R.N.; McSorley, R.; Dickson, D.S.
 Lake Alfred, Fla. : Society of Nematologists; 1991 Oct.
 Journal of nematology v. 23 (4,suppl.): p. 668-672; 1991 Oct.  Includes
 references.
 
 Language:  English
 
 Descriptors: Florida; Zea mays; Sorghum bicolor; Glycine max; Meloidogyne
 incognita; Pratylenchus; CRiconemella; Population density; Cropping systems;
 Rotations
 
 Abstract:  Final densities (Pf) of Meloidogyne incognita nd Pratylenchus spp.
 increased more than ten-fold over initial densities (Pi) on corn (Zea mays)
 cultivars grown at three sites in north Florida. The Pf of M. incognita
 following sorghum (Sorghum bicolor) were much lower (P less than or equal to
 0.001) than Pf following corn at the two sites in which sorghum was grown. At
 one of these sites, Pf of M. incognita was less than or equal to 5/100 cm3
 soil, and at the other site Pf < Pi. At one site, population densities of
 Criconemella sphaerocephala increased to higher levels on sorghum than on corn,
 but Pf of Pratylenchus spp. were greater (P less than or equal to 0.01) on
 corn. Few differences in nematode densities were observed among the different
 corn cultivars tested.
 
 
 243                                                  NAL Call. No.: SB998.N4N4
 Nematode management in minimum-till soybean with resistant cultivars, rye
 rotation, and aldicarb.
 Minton, N.A.
 Auburn, Ala. : Organization of Tropical American Nematologists; 1992 Jun.
 Nematropica v. 22 (1): p. 21-28; 1992 Jun.  Includes references.
 
 Language:  English
 
 Descriptors: Georgia; Glycine max; Cultivars; Pest resistance; Meloidogyne
 incognita; Paratrichodorus minor; Pratylenchus brachyurus; Rotations; Secale
 cereale; Nematode control; Minimum tillage
 
 
 244                                               NAL Call. No.: S544.5.A17W74
 Nematodes of alfalfa.
 O'Bannon, J.H.; Peaden, R.
 S.l. : Cooperative Extension, Washington State University, etc. :.; 1991 Jun.
 WREP - Western Region Extension Publication - Cooperative Extension Service
 v.): 4 p.; 1991 Jun.  In the series analytic: Alfalfa seed production and pest
 management.
 
 Language:  English
 
 Descriptors: Pacific states of U.S.A.; Medicago sativa; Seed production;
 Nematoda; Pest resistance; Rotations
 
 
 245                                                   NAL Call. No.: SB610.W39
 Nicosulfuron, primisulfuron, imazethapyr, and DPX-PE350 injury to succeeding
 crops.
 Johnson, D.H.; Jordan, D.L.; Johnson, W.G.; Talbert, R.E.; Frans, R.E.
 Champaign, Ill. : The Weed Science Society of America; 1993 Jul.
 Weed technology : a journal of the Weed Science Society of America v. 7 (3): p.
 641-644; 1993 Jul.  Includes references.
 
 Language:  English
 
 Descriptors: Arkansas; Cabt; Zea mays; Gossypium hirsutum; Glycine max; Sorghum
 bicolor; Oryza sativa; Rotations; Sequential cropping; Crop damage; Abiotic
 injuries; Weed control; Chemical control; Imazethapyr; Sulfonylurea herbicides;
 Persistence; Residual effects; Sowing date
 
 
 246                                                   NAL Call. No.: 100 M69MI
 Nitrogen and vetch improve cotton yield.
 Broadway, R.
 Mississippi State, Miss. : The Station; 1992 Apr.
 MAFES research highlights - Mississippi Agricultural and Forestry Experiment
 Station v. 55 (4): p. 4; 1992 Apr.
 
 Language:  English
 
 Descriptors: Mississippi; Gossypium; Crop yield; Vicia; Nitrogen fertilizers;
 Cover crops; No-tillage
 
 
 247                                                      NAL Call. No.: 30 AD9
 Nitrogen dynamics and management in rice--legume cropping systems.
 Buresh, R.J.; Datta, S.K.De
 San Diego, Calif. : Academic Press; 1991.
 Advances in agronomy v. 45: p. 1-59; 1991.  Literature review.  Includes
 references.
 
 Language:  English
 
 Descriptors: Philippines; Asia; Oryza sativa; Legumes; Cropping systems; Green
 manures; Losses from soil systems; Mineralization; Nitrogen cycle; Nitrogen
 fertilizers; Nitrogen fixation; Residual effects; Soil fertility; Yield
 response functions; Agricultural research; Literature reviews
 
 
 248                                                    NAL Call. No.: 23 AU792
 Nitrogen fertiliser response of wheat in lupin-wheat, subterranean
 clover-wheat and continuous wheat rotations.
 Mason, M.G.; Rowland, I.C.
 East Melbourne : Commonwealth Scientific and Industrial Research Organization;
 1990.
 Australian journal of experimental agriculture v. 30 (2): p. 231-236; 1990.
 Includes references.
 
 Language:  English
 
 Descriptors: Western australia; Lupinus albus; Lupinus angustifolius; Trifolium
 subterraneum; Triticum; Nitrogen fertilizers; Rotations; Yield
 response functions
 
 
 249                                                     NAL Call. No.: 4 AM34P
 Nitrogen fertilizer recovery by corn in monoculture and rotation systems.
 Varvel, G.E.; Peterson, T.A.
 Madison, Wis. : American Society of Agronomy; 1990 Sep.
 Agronomy journal v. 82 (5): p. 935-938; 1990 Sep.  Includes references.
 
 Language:  English
 
 Descriptors: Nebraska; Zea mays; Monoculture; Continuous cropping; Rotations;
 Glycine max; Avena sativa; Trifolium pratense; Sorghum bicolor; Nitrogen
 fertilizers; Nutrient uptake; Nitrogen; Recovery; Analytical methods
 
 Abstract:  Crop rotations including legumes have increased in importance
 because of their potential to reduce large inorganic N fertilizer needs for
 corn [Zea mays L.) and other crops. This study was conducted to determine N
 fertilizer recovery by corn in monoculture and rotational systems. Corn was
 grown under rainfed conditions on a Sharpsburg silty clay loam (fine,
 montmorillinitic, mesic, Typic Argiudoll) in four cropping systems: (i)
 continuous corn monoculture, ii) a 2-yr soybean [Glycine max (L.) Merr.]-corn
 rotation, (iii) a 4-yr rotation of oat [Avena sativa L.)] + clover [80%
 Melilotus officinalis (L.) and 20% Trifolium pratense]-grain sorghum [Sorghum
 bicolor (L.)]-soybean-corn, and (iv) a 4-yr rotation of soybean-grain sorghum-
 oat + clover-corn at Mead, NE. Broadcast applications of 15N-depleted NH4NO3
 were made at 90 and 180 kg N ha-1 in 1985 and 1986 to evaluate N fertilizer
 recovery by corn in each cropping system using isotopic methods. Nitrogen
 recovery determined by isotopic methods was significantly higher for corn in
 rotation vs. corn in monoculture, averaging 58.6 vs. 52.3% and 49.8 vs. 43.4%
 at the 90 and 180 kg N ha-1 rates, respectively. In contrast, fertilizer N
 recovery estimated by the difference method was much greater in continuous corn
 vs. N recovery in corn following oat + clover in the 4-yr rotation. These
 differences indicated that N fertilizer applied to corn in each cropping system
 appeared to be entering different sizes and types of organic soil N pools,
 resulting in apparent differences in N immobilization. Our results demonstrate
 problems exist in estimating fertilizer N recovery with both methods (isotope
 or difference) and before accurate N recovery estimates by corn or any other
 crop can be made in complex soil and crop management systems, procedures must
 be developed to explicitly follow N fertilizer pathways (immobilization,
 denitrification, volatilization, leaching, etc.). Until that time, correct
 interpretations with either method
 
 
 250                                                     NAL Call. No.: 4 AM34P
 Nitrogen fertilizer recovery by grain sorghum in monoculture and rotation
 systems.
 Varvel, G.E.; Peterson, T.A.
 Madison, Wis. : American Society of Agronomy; 1991 May.
 Agronomy journal v. 83 (3): p. 617-622; 1991 May.  Includes references.
 
 Language:  English
 
 Descriptors: Nebraska; Sorghum bicolor; Monoculture; Rotations; Glycine max;
 Zea mays; Avena sativa; Trifolium pratense; Melilotus officinalis; Nitrogen
 fertilizers; Isotopes; Radioactive tracers; Application rates; Recovery;
 Nutrient uptake; Nitrogen; Crop yield; Grain; Stover; Nitrogen content
 
 Abstract:  Grain sorghum [Sorghum bicolor (L.) Moench] has become a major
 dryland crop for the Great Plains, but information on production in rotations
 is limited. This study was conducted to determine N fertilizer recovery and use
 by grain sorghum in monoculture and rotational systems. Grain sorghum was grown
 under rainfed conditions on a Sharpsburg silty clay loam (fine,
 montmorillonitic, mesic, Typic Argiudoll) in: (i) continuous grain sorghum
 monoculture, (ii) a 2-yr soybean [Glycine max (L.) Merr.]-grain sorghum
 rotation, (iii) a 4-yr rotation of soybean-corn [Zea mays L.]-oat [Avena sativa
 (L.)] + clover [80% Melilotus officinalis (L.) and 20% Trifolium pratense
 (L.)]-grain sorghum, and (iv) a 4-yr rotation of oat + clover-corn-soybean-
 grain sorghum at Mead, NE. Broadcast applications of 15N-depleted NH4NO3 were
 made at 90 and 180 kg N ha(-1) in 1985 and 1986 to evaluate N fertilizer
 recovery. Fertilizer N recovery determined by isotopic methods was
 significantly higher for grain sorghum in monoculture (64.9%) vs. grain sorghum
 in rotation (54.9%). Fertilizer N recovery estimated by the difference method
 ranged from 118.5% in continuous grain sorghum to 9.1% in sorghum following oat
 + clover. Differences in N-recovery results by the isotope and difference
 methods indicated N fertilizer applied to grain sorghum in various cropping
 systems appeared to be entering different organic soil-N pools. These results
 substantiate the importance of the mineralization-immobilization turnover (MIT)
 effect in N-isotope experiments and the necessity for careful interpretation of
 N-recovery results, especially between complex cropping systems.
 
 
 251                                                     NAL Call. No.: 4 AM34P
 Nitrogen fertilizer recovery by soybean in monoculture and rotation systems.
 Varvel, G.E.; Peterson, T.A.
 Madison, Wis. : American Society of Agronomy; 1992 Mar.
 Agronomy journal v. 84 (2): p. 215-218; 1992 Mar.  Includes references.
 
 Language:  English
 
 Descriptors: Nebraska; Glycine max; Rotations; Zea mays; Sorghum bicolor; Avena
 sativa; Melilotus officinalis; Monoculture; Fertilizer requirement
 determination; Nitrogen; Recovery; Nutrient uptake; Nitrogen fertilizers;
 Application rates; Nitrate nitrogen; Leaching
 
 Abstract:  Crop rotations including soybean [Glycine max (L.) Merr.] have
 increased in importance because of their potential to increase yields, reduce
 expenditures for pesticides and fertilizer, and increase net returns to the
 producer. Despite the importance of soybean in the USA, there is a lack of
 understanding of how N affects soybean in rotation systems. This study was
 conducted to determine the effects of rotation and N fertilization on N uptake
 and recovery by soybean. Soybean was grown under rainfed conditions on a
 Sharpsburg silty clay loam (fine, montmorillonitic, mesic, Typic Argiudoll) in
 five cropping systems: (i) continuous soybean monoculture, (ii) a 2-yr corn
 (Zea mays L.)-soybean rotation, (iii) a 2-yr grain sorghum [sorghum bicolor
 (L.) Moench]-soybean rotation, (iv) a 4-yr rotation of corn-oat [Avena sativa
 L.)] + clover [80% Melilotus officinalis (L.) and 20% Trifolium pratense]-grain
 sorghum-soybean, and (v) a 4-yr rotation of grain sorghum-oat + clover-corn-
 soybean at Mead, NE. Broadcast applications of 15N-depleted NH4NO3 were made at
 34 and 68 kg N ha-1 in 1985 and 1986 to evaluate N fertilizer recovery by
 soybean in each cropping system. Nitrogen recovery determined by isotope
 analyses was approximately 50% in all rotation systems and was not
 significantly affected by rotation or N rate. Large amounts of N were removed
 by the harvested soybean seed in all systems (150 to 200 kg N ha-1), regardless
 of N fertilizer applications. Soybean can act as a N sink and potentially aid
 in reducing the amount of soil N available for leaching. Since soybean grown in
 a rotation can utilize soil or fertilizer N along with the other benefits of
 rotations, soybean shows promise as a crop that may help reduce the leaching of
 nitrate-N in to ground water.
 
 
 252                                                      NAL Call. No.: 30 AD9
 Nitrogen fixation by legumes in tropical and subtropical agriculture.
 Peoples, M.B.; Herridge, D.F.
 San Diego, Calif. : Academic Press; 1990.
 Advances in agronomy v. 44: p. 155-223. ill; 1990.  Literature review.
 Includes references.
 
 Language:  English
 
 Descriptors: Cover crops; Fodder crops; Shrubs; Trees; Legumes; Nitrogen
 fixation; Quantitative analysis; Subtropical crops; Tropical crops; Crop
 production; Crop residues; Decomposition; Green manures; Literature reviews;
 Rhizobiaceae; Soil inoculation; Plant breeding; Crop management; Soil
 management; Animal production
 
 
 253                                                NAL Call. No.: 100 SO82 (3)
 Nitrogen management in a corn soybean rotation.
 Gerwing, J.; Gelderman, R.; Sorensen, D.
 Brookings, S.D. : The Station; 1992 Oct.
 TB - Agricultural Experiment Station, South Dakota State University (99): 4 p.;
 1992 Oct.  In the series analytic: Soil science research in the Plant Science
 Department : 1991 Annual Report. Soil PR 91-32.
 
 Language:  English
 
 Descriptors: South Dakota; Zea mays; Glycine max; Nitrogen; Rotations;
 Environmental impact; Groundwater pollution; Application rates; Soil testing;
 Crop yield
 
 
 254                                                NAL Call. No.: 100 SO82 (3)
 Nitrogen management in a corn soybean rotation.
 Gerwing, J.; Gelderman, R.; Sorenson, D.
 Brookings, S.D. : The Station; 1991.
 TB - Agricultural Experiment Station, South Dakota State University (97): 5 p.
 (soil PR 90-27); 1991.
 
 Language:  English
 
 Descriptors: South Dakota; Zea mays; Glycine max; Rotations; Nitrogen; Movement
 in soil; Groundwater pollution
 
 
 255                                                     NAL Call. No.: 10 J822
 Nitrogen nutrition of wheat following different crops.
 Echeverria, H.E.; Navarro, C.A.; Andrade, F.H.
 Cambridge : Cambridge University Press; 1992 Apr.
 The Journal of agricultural science v. 118 (pt.2): p. 157-163; 1992 Apr.
 Includes references.
 
 Language:  English
 
 Descriptors: Argentina; Triticum aestivum; Glycine max; Helianthus annuus; Zea
 mays; Nitrogen content; Nitrogen fertilizers; Plant nutrition; Rotations;
 Seeds; Crop yield; Environmental temperature; Precipitation
 
 
 256                                                 NAL Call. No.: S592.7.A1S6
 Nitrogen release from the leaves of some tropical legumes as affected by their
 lignin and polyphenolic contents.
 Palm, C.A.; Sanchez, P.A.
 Exeter : Pergamon Press; 1991.
 Soil biology and biochemistry v. 23 (1): p. 83-88; 1991.  Includes references.
 
 Language:  English
 
 Descriptors: Leguminosae; Tropical crops; Leaves; Nitrogen; Lignin;
 Polyphenols; Plant composition; Decomposition; Mineralization; Acid soils;
 Tropical soils; Live mulches; Green manures; Cover crops
 
 Abstract:  Leguminous plant materials used as mulches, green manures and cover
 crops are generally assumed to provide a readily-available source of N to
 crops. However, little is known about the chemical composition and N release
 patterns of the variety of legumes being used in tropical agroecosystems. N
 release patterns from the leaflets of 10 tropical legumes and rice straw were
 determined in a laboratory experiment. Ground leaf material was allowed to
 decompose in an acid soil (pH 4.5) for 8 weeks and the soil was analyzed
 periodically for extractable NH4(+)-N and NO3(-)-N. N release in the soil plus
 plant material were compared to that of the soil without plant material added
 and related to the N, lignin and polyphenolic concentrations of the leaflets.
 Three patterns of net N mineralization emerged during the 8-weeks. One pattern
 exhibited by the control soil, rice straw and leaves of two of the leguminous
 plants was a low, positive net mineralization. Another pattern showed much
 higher rates of mineralization than the control soil and the third pattern
 showed initial net immobilization followed by low but positive net
 mineralization rates. The amount of N mineralized during the 8 weeks as
 compared to the control soil ranged from +46 to -20% of the N added in plant
 material. Net mineralization was not correlated to % N or % lignin in the leaf
 material but was found to be negatively correlated to the polyphenolic
 concentration, r = -0.63, or the polyphenolic-to-N ratio, r = -0.75.
 Mineralization in excess of the control soil was found only for materials with
 a polyphenolic-to-N ratio <0.5. Mechanisms to explain the low mineralization by
 materials high in polyphenolics include the formation of stable polymers
 between polyphenolics and amino groups, and nitrosation, a chemical reaction of
 nitrite (NO2(-)) with polyphenolics. Our results show that leguminous plant
 material with a high polyphenolic content or polyphenolic-to-N ratio may not be
 a readily-available source of N. 
 
 
 257                                                   NAL Call. No.: QH301.A76
 Nitrogen residues from peas and beans and the response of the following cereal
 to applied nitrogen.
 Sylvester-Bradley, R.; Cross, R.B.
 Wellesbourne, Warwick : The Association of Applied Biologists; 1991.
 Aspects of applied biology (27): p. 293-298; 1991.  In the series analytic:
 Production and protection of legumes / edited by R.J. Froud-Williams, P.
 Gladders, M.C. Heath, J.F. Jenkyn, C.M. Knott, A. Lane and D. Pink.  Includes
 references.
 
 Language:  English
 
 Descriptors: England; Triticum; Cereals; Pisum sativum; Vicia faba; Residual
 effects; Rotations; Crop yield
 
 
 258                                                     NAL Call. No.: 26 T754
 Nitrogen supplied to corn by legumes in a Central Amazon Oxisol.
 Smyth, T.J.; Cravo, M.S.; Melgar, R.J.
 London : Butterworth-Heinemann; 1991 Oct.
 Tropical agriculture v. 68 (4): p. 366-372; 1991 Oct.  Includes references.
 
 Language:  English
 
 Descriptors: Brazil; Indigofera tinctoria; Mucuna aterrima; Vigna unguiculata;
 Zea mays; Crop residues; Green manures; Legumes; Nitrogen fertilizers; Urea
 nitrates; Biomass production; Crop yield; Dry matter; Humid tropics; Oxisols;
 Soil chemistry
 
 
 259                                                   NAL Call. No.: QK867.J67
 Nitrogen uptake within sequential vegetable cropping systems.
 Sanders, D.C.; Bandele, O.A.; Miller, C.H.; Nash, A.
 New York, N.Y. : Marcel Dekker; 1993.
 Journal of plant nutrition v. 16 (6): p. 1119-1136; 1993.  Includes references.
 
 Language:  English
 
 Descriptors: Lycopersicon esculentum; Phaseolus vulgaris; Zea mays; Brassica
 oleracea var. italica; Brassica oleracea; Cucurbita pepo; Nitrogen; Nutrient
 uptake; Nitrogen content; Sequential cropping
 
 Abstract:  A study was conducted to determine the effect of previous crop,
 nitrogen (N) rate and planting density on N uptake within different vegetable
 cropping sequences. Spring crops included tomato (Lycopersicon esculentum
 Mill.), snap bean (Phaseolus vulgaris L.) and sweet corn (Zea mays L.). Each
 spring crop was followed in the fall by broccoli (Brassica oleracea L. Italica
 group), collard (Brassica oleracea L. Acephala group) and pumpkin (Cucurbita
 pepo L.). Higher N rates resulted in greater N uptake for all plants at some
 point in the growing season. Final N accumulation exceeded N fertilizer applied
 at 1 or more N rates for all six crops. However, higher N rates resulted in
 greater final N accumulation only with the tomato/broccoli sequence. Plants
 grown at lower density generally had greater N accumulation per plant, but N
 uptake per hectare was greater for the high density planting. The greatest
 previous crop effect was in 1984 when N accumulation for pumpkin following
 tomato exceeded that of other sequences. Cultural practices probably led to
 these differences.
 
 
 260                                                   NAL Call. No.: 56.8 J822
 Nonpoint source pollution impacts of alternative agricultural management
 practice in Illinois: a simulation study.
 Phillips, D.L.; Hardin, P.D.; Benson, V.W.; Baglio, J.V.
 Ankeny, Iowa : Soil Conservation Society of America, 1946-; 1993 Sep.
 Journal of soil and water conservation v. 48 (5): p. 449-457; 1993 Sep.
 Includes references.
 
 Language:  English
 
 Descriptors: Illinois; Cabt; Erosion; Carbon; Nutrient balance; Rotations;
 Water pollution; No-tillage; Alternative farming; Innovation adoption;
 Simulation models; Zea mays; Glycine max; Crop yield; Nitrogen; Phosphorus;
 Runoff
 
 
 261                                                  NAL Call. No.: S539.5.J68
 No-till vs. conventional tillage for late-planted corn following hay harvest.
 Smith, M.A.; Carter, P.R.; Imholte, A.A.
 Madison, Wis. : American Society of Agronomy; 1992 Apr.
 Journal of production agriculture v. 5 (2): p. 261-264; 1992 Apr.  Includes
 references.
 
 Language:  English
 
 Descriptors: Wisconsin; Zea mays; No-tillage; Tillage; Hay; Cover crops;
 Medicago sativa; Hybrids; Maturation period; Soil temperature; Soil water;
 Seedling emergence; Dry matter; Weight; Crop yield; Plant height; Returns;
 Costs; Planting date
 
 
 262                                                      NAL Call. No.: SB1.H6
 A no-tillage tomato production system using hairy vetch and subterranean
 clover mulches.
 Abdul-Baki, A.A.; Teasdale, J.R.
 Alexandria, Va. : The American Society for Horticultural Science; 1993 Feb.
 HortScience : a publication of the American Society for Horticultural Science
 v. 28 (2): p. 106-108; 1993 Feb.  Includes references.
 
 Language:  English
 
 Descriptors: Maryland; Cabt; Lycopersicon esculentum; Vicia villosa; Trifolium
 subterraneum; Cover crops; Mulches; No-tillage; Fruits; Maturity; Crop yield;
 Planting date; Earliness; Low input agriculture
 
 Abstract:  A novel approach is described for using two winter annual legumes -
 hairy vetch (Vicia villosa L. Roth.) and 'Mt. Barker' subterranean clover
 (Trifolium subterraneum L.) - as cover crops and plant mulches in tomato
 (Lycopersicon esculentum Mill.) production. The approach calls for sowing the
 cover crops in the fall in prepared beds, mowing the cover crops with a high-
 speed flail mower immediately before transplanting the tomato seedlings into
 the field in early May, and then transplanting the seedlings into the beds with
 minimal interruption of the soil or mulch cover. Plants in the vetch treatment
 with no tillage produced a higher yield than those grown under black
 polyethylene, paper, or no mulch in conventional systems. Both plant mulches
 delayed fruit maturity by approximately 10 days relative to black polyethylene
 mulch. The proposed approach eliminates tillage, reduces the need for applying
 synthetic fertilizers and herbicides, and is adapted to large- and small-scale
 tomato production in a low-input, no-tillage system. It also may be used to
 produce other vegetables. 
 
 263                                                   NAL Call. No.: 79.9 N814
 Oat and soybean yields in crownvetch and other cover crops.
 Hartwig, N.L.
 College Park, Md. : The Society; 1991.
 Proceedings of the annual meeting - Northeastern Weed Science Society v. 45: p.
 122-125; 1991.  Meeting held January 8-10, 1991, Baltimore, Maryland.
 Includes references.
 
 Language:  English
 
 Descriptors: Avena sativa; Glycine max; Crop yield; Coronilla varia; Cover
 crops; Live mulches
 
 
 264                                                  NAL Call. No.: S539.5.J68
 Optimal rates of nitrogen fertilization for first-year corn after alfalfa.
 Morris, T.F.; Blackmer, A.M.; El-Hout, N.M.
 Madison, WI : American Society of Agronomy, c1987-; 1993 Jul.
 Journal of production agriculture v. 6 (3): p. 344-350; 1993 Jul.  Includes
 references.
 
 Language:  English
 
 Descriptors: Iowa; Cabt; Zea mays; Medicago sativa; Rotations; Nitrogen
 fertilizers; Application rates; Fertilizer requirement determination
 
 
 265                                                 NAL Call. No.: S592.7.A1S6
 Organic matter-microbial biomass relationships in field experiments under
 tropical conditions: effects of inorganic fertilization and organic
 amendments.
 Goyal, S.; Mishra, M.M.; Hooda, I.S.; Singh, R.
 Exeter : Pergamon Press; 1992 Nov.
 Soil biology and biochemistry v. 24 (11): p. 1081-1084; 1992 Nov.  Includes
 references.
 
 Language:  English
 
 Descriptors: India; Triticum aestivum; Pennisetum Americanum; Semiarid soils;
 Soil organic matter; Soil flora; Biomass; Urea; Application rates; Farmyard
 manure; Wheat straw; Green manures; Biological activity in soil; Crop yield;
 Nutrient uptake; Carbon; Nitrogen; Tropical climate
 
 
 Abstract:  The analysis of continuous fertilizer and manurial experiments in
 tropical conditions of India have shown that soil microbial biomass C and N
 increased with balanced fertilization. The additions of organic amendments
 increased microbial biomass even when the organic C content of the soil did not
 increase. The increase in microbial biomass was attributed to better plant
 growth resulting in higher rhizodeposition. The crop yields and N uptake were
 higher with the addition of farm yard manure or Sesbania green manure.
 
 
 266                                                     NAL Call. No.: 4 AM34P
 Overview of long-term agronomic research.
 Mitchell, C.C.; Westerman, R.L.; Brown, J.R.; Peck, T.R.
 Madison, Wis. : American Society of Agronomy; 1991 Jan.
 Agronomy journal v. 83 (1): p. 24-29; 1991 Jan.  Paper presented at the
 Symposium on Long-Term Field Research, October 17-18, 1989.  Includes
 references.
 
 Language:  English
 
 Descriptors: Illinois; Missouri; Oklahoma; Alabama; Agronomy; Field crops;
 Field experimentation; Research projects; Long term experiments; Historical
 records; Historic sites; Sustainability; Rotations; Soil fertility
 
 Abstract:  Renewed interest in low-input and sustainable crop production has
 rekindled interest in long-term agronomic research. Research plots that have
 been monitored continuously since the late 19th Century exist in several
 states. Twenty-five experiments have been identified that have been monitored
 for over 25 yr; 12 of these are more than 50 yr old. Yield and treatment
 records provide valuable information on the effects of cropping systems,
 tillage, manuring and fertilization practices on yields and on soil physical
 and chemical properties. Most of these very early tests were non-replicated
 studies using large plots and crop rotation systems. Four of America's oldest,
 continuous agronomic research tests were reviewed in more detail: (i) Illinois'
 "Morrow Plots" (c. 1876), (ii) Missouri's "Sanborn Field" (c. 1888), (iii)
 Oklahoma's "Magruder Plots" (c. 1892) and (iv) Alabama's "Old Rotation" (c.
 1896). All of these are listed on the National Register of Historical Places.
 These studies document that long-term crop production can be sustained and
 improved in different regions and on different soils of the USA. Long-term
 studies have shown that crop rotations and attention to recognized and
 established soil fertility practices, which may or may not include legumes and
 manuring, are essential to maintaining high, sustained production.
 
 
 267                                                  NAL Call. No.: 464.8 P692
 Pathogenicity of four Pythium species to wheat, barley, peas and lentils.
 Ingram, D.M.; Cook, R.J.
 Oxford : Blackwell Scientific Publications; 1990 Mar.
 Plant pathology v. 39 (1): p. 110-117; 1990 Mar.  Includes references.
 
 Language:  English
 
 Descriptors: Washington; Idaho; Triticum aestivum; Hordeum vulgare; Lens
 culinaris; Pisum sativum; Rotations; Host specificity; Pythium irregulare;
 Pythium; Pythium ultimum; Pathogenicity; Growth retardation; Soil temperature;
 Seedlings; Ammonium sulfate; Chaff
 
 
 268                                                NAL Call. No.: S544.3.N6N62
 Peanut production practices.
 Sullivan, G.A.
 Raleigh, N.C. : The Service; 1991 Dec.
 AG - North Carolina Agricultural Extension Service, North Carolina State
 University v.): p. 9-22; 1991 Dec.  In the series analytic: 1992 Peanuts.
 
 Language:  English
 
 Descriptors: North Carolina; Arachis hypogaea; Cultivars; Crop production; Crop
 yield; Rotations; Soil management; Soil resources; Fertilizers; Lime; Nitrogen;
 Calcium; Manganese; Boron; Application rates; Site preparation
 
 
 269                                                NAL Call. No.: S494.5.S86S8
 Pearl lupine (Lupinus mutabilis) as a green manure crop in the highlands of
 Bhutan.
 Roder, W.; Kharel, D.R.; Gurung, P.R.; Dukpa, P.
 Binghamton, N.Y. : Food Products Press; 1993.
 Journal of sustainable agriculture v. 3 (2): p. 9-20; 1993.  Includes
 references.
 
 Language:  English
 
 Descriptors: Bhutan; Lupinus mutabilis; Green manures; Highlands; Soil organic
 matter; Biomass; Solanum tuberosum; Crop production; Nitrogen content
 
 
 270                                                     NAL Call. No.: 10 J822
 Persistence of herbage treatment effects in barley and consequences for
 subsequent crop experimentation.
 Fairey, N.A.; Lefkovitch, L.P.
 Cambridge : Cambridge University Press; 1993 Feb.
 The Journal of agricultural science v. 120 (pt.1): p. 25-32; 1993 Feb.
 Includes references.
 
 Language:  English
 
 Descriptors: Alberta; Hordeum vulgare; Grasses; Legumes; Crop management; Crop
 quality; Crop yield; Experimental design; Ammonium nitrate; Rotation; Tillage
 
 
 271                                                   NAL Call. No.: 75.8 P842
 Petiole nitrate content of Maine-grown Russet Burbank and Shepody potatoes in
 response to varying nitrogen rate.
 Porter, G.A.; Sisson, J.A.
 Orono, Me. : Potato Association of America; 1991 Aug.
 American potato journal v. 68 (8): p. 493-505; 1991 Aug.  Includes references.
 
 Language:  English
 
 Descriptors: Maine; Solanum tuberosum; Cultivars; Varietal reactions; Nitrogen
 fertilizers; Application rates; Rotations; Avena sativa; Trifolium pratense;
 Nutrient uptake; Nitrate nitrogen; Plant analysis; Petioles; Plant composition;
 Crop growth stage; Maturity stage; Crop yield; Tubers; Fertilizer requirement
 determination
 
 
 272                                                     NAL Call. No.: 4 AM34P
 Phosphorus management for continuous corn-cowpea production in a Brazilian
 Amazon Oxisol.
 Smyth, T.J.; Cravo, M.S.
 Madison, Wis. : American Society of Agronomy; 1990 Mar.
 Agronomy journal v. 82 (2): p. 305-309; 1990 Mar.  Includes references.
 
 Language:  English
 
 Descriptors: Brazil; Zea mays; Vigna unguiculata; Rotations; Oxisols;
 Phosphorus fertilizers; Phosphorus residual effect; Band placement;
 Broadcasting; Crop yield; Maximum yield
 
 Abstract:  Although Oxisols occupy extensive areas in the Amazon, few studies
 have addressed their fertilizer P requirements for sustained, long-term crop
 production. This field study was conducted to evaluate initial and long-term
 responses to P rates and placement by corn (Zea mays L.) and cowpea (Vigna
 unguiculata L.) when grown in annual rotation during five consecutive years in
 a Xanthic Hapludox (clayey, kaolinitic, isohyperthermic) near Manaus, Brazil.
 Effects on yields of sole broadcast P rates of 0, 22, 44, 88 and 176 kg ha-1 in
 split-plot combination with subplot banded P rates of 0, 11, 22 and 44 kg ha-1
 were evaluated over 11 total crops. Banded P at 11 kg ha-1 was applied to every
 crop and rates of 22 and 44 kg P ha-1 were only applied to the initial eight
 and four crops, respectively. Residual effect of broadcast P, as
 measured by both yields and Mehlich 1 soil P, were greater at high rates.
 Although cowpea yields were increased up to the highest band rate, no response
 in corn yields were observed beyond the rate of 22 kg P ha-1. At equal amounts
 of applied P, banded P provided greater yields than broadcast P during the
 initial crops. Total corn and/or cowpea yields, after 11 crops, were similar
 for all broadcast and band combinations at equal amounts of total applied P.
 The absence of a cumulative yield difference among placement methods indicated
 that banded placement of 22 and 44 kg P ha-1 to corn and cowpea, respectively,
 would be the best method of applying P to sustain long-term crop production
 under the manual tillage practices used in the region.
 
 
 273                                                NAL Call. No.: S544.3.N6N62
 Plant disease control.
 Bailey, J.E.
 Raleigh, N.C. : The Service; 1991 Dec.
 AG - North Carolina Agricultural Extension Service, North Carolina State
 University v.): p. 78-92; 1991 Dec.  In the series analytic: 1992 Peanuts.
 
 Language:  English
 
 Descriptors: North Carolina; Arachis hypogaea; Plant disease control;
 Rotations; Plant diseases; Pesticides; Fungicides; Nematoda; Nematicides;
 Application rates; Application date; Cultivars; Disease resistance; Harvesting;
 Organic farming
 
 
 274                                                    NAL Call. No.: 56.9 SO3
 Plant-available nitrogen from lentil and wheat residues during a subsequent
 growing season.
 Bremer, E.; Van Kessel, C.
 Madison, Wis. : The Society; 1992 Jul.
 Soil Science Society of America journal v. 56 (4): p. 1155-1160; 1992 Jul.
 Includes references.
 
 Language:  English
 
 Descriptors: Saskatchewan; Triticum aestivum; Green manures; Lentils; Straw;
 Wheat straw; Ammonium sulfate; Comparisons; Nitrogen; Nutrient availability;
 Mineralization; Immobilization; Nutrient uptake; Losses from soil; Seasonal
 fluctuations
 
 Abstract:  Lentil (Lens culinaris Medikus) is being grown increasingly on the
 Canadian prairies as a pulse or green manure crop, and may increase N
 availability to a succeeding crop. This study was designed to compare the
 effects of lentil green manure, lentil straw, and wheat (Triticum aestivum L.)
 straw on plant-available N during the growing season after application. The
 fate of 15N from fall-applied (1988) lentil green manure, lentil straw, and
 wheat straw and spring-applied (1989) fertilizer (NH4)2SO4 was determined four
 times during the 1989 growing season at a field site located at Outlook,
 Saskatchewan, Canada, on a Bradwell sandy loam (Typic Boroll). Denitrification
 and leaching losses of 15N from added lentil and wheat straw were negligible,
 but 24 and 30% of the 15N in lentil green manure and fertilizer, respectively,
 were lost in the 6-wk period after planting (8 May 1989). By wheat harvest (8
 Aug. 1989), 7% of the 15N in lentil and wheat straw and 37% of the 15N in
 lentil green manure were mineralized. Addition of green manure increased net
 mineralization of indigenous soil N at the time of planting by 0.4 g m-2,
 equivalent to 10% of added green manure N. Immobilization of soil and
 fertilizer N was similar for lentil and wheat straw. The smaller fraction of
 15N assimilated from green manure (19%) than from fertilizer (34%) by wheat was
 due solely to less net mineralization of green-manure N rather than net
 immobilization of fertilization N. Of the 15N added in lentil and wheat straw,
 5.5% was assimilated by wheat. Thus, lentil straw was not a significant source
 of N in this study, while approximately 40% of the N in lentil green manure was
 potentially available for plant uptake.
 
 
 275                                                   NAL Call. No.: 75.8 P842
 Plant-parasitic nematodes in the potato growing areas of Maine.
 Huettel, R.N.; Francl, L.J.; Reise, R.W.; Meyer, S.L.F.; Henn, R.A.
 Orono, Me. : Potato Association of America; 1991 Jun.
 American potato journal v. 68 (6): p. 345-354; 1991 Jun.  Includes references.
 
 Language:  English
 
 Descriptors: Maine; Solanum tuberosum; Rotations; Fagopyrum; Avena sativa;
 Trifolium; Plant parasitic nematodes; Pratylenchus penetrans; Pratylenchus
 crenatus; Meloidogyne hapla; CRiconemella; Paratylenchus; Tylenchorhynchus;
 Helicotylenchus; Population density; Disease prevalence; Verticillium albo-
 atrum; Verticillium dahliae
 
 
 276                                                  NAL Call. No.: QL391.N4R4
 Population dynamics of Hirschmanniella mucronata and H. oryzae on Sesbania
 rostrata, Aeschynomene afraspera and rice cv. IR 58.
 Hendro, S.M.E.; Prot, J.C.; Madamba, C.P.
 Montrouge : Gauthier-Villars; 1992.
 Fundamental and applied nematology v. 15 (2): p. 167-172; 1992.  Includes
 references.
 
 Language:  English
 
 Descriptors: Oryza sativa; Hirschmanniella mucronata; Hirschmanniella oryzae;
 Population density; Sesbania; Aeschynomene; Rotations; Nematode control
 
 
 277                                                 NAL Call. No.: QL391.N4J62
 Population dynamics of plant-parasitic nematodes on cover crops of corn and
 sorghum.
 McSorley, R.; Gallaher, R.N.
 Lakeland, Fla. : Society of Nematologists; 1993 Sep.
 Journal of nematology v. 25 (3): p. 446-453; 1993 Sep.  Includes references.
 
 Language:  English
 
 Descriptors: Florida; Cabt; Zea mays; Glycine max; Sorghum bicolor; Meloidogyne
 incognita; CRiconemella; Paratrichodorus; Pratylenchus; Population density;
 Rotations
 
 Abstract:  Buildup of plant-parasitic nematode populations on corn (Zea mays),
 soybean (Glycine max), and sorghum (Sorghum bicolor) were compared in 1991 and
 1992. Final population densities (Pf) of Meloidogyne incognita were lower
 following sorghum than after soybean in both seasons, and Pf after sorghum was
 lower than Pf after corn in 1992. In both seasons, Pf differed among the
 sorghum cultivars used. No differences in Pf on corn, sorghum, and soybean were
 observed for Criconemella spp. (a mixture of C. sphaerocephala and C. ornata)
 or Paratrichodorus minor in either season. Pf levels of Pratylenchus spp. (a
 mixture of P. brachyurus and P. scribneri) were greatest after corn in 1992,
 but no differences with crop treatments were observed in 1991. When data from
 field tests conducted with corn and sorghum during the past four seasons were
 pooled, negative linear relationships between ln(Pf/Pi) and ln(Pi) were
 observed for Criconemella spp. and P. minor on each crop, and for M. incognita
 on corn (Pi = initial population density). Although ln(Pf/Pi) and ln(Pi) were
 not related for M. incognita with pooled sorghum data, separate relationships
 were derived for various sorghum cultivars. Regression equations from pooled
 data were used to obtain estimates of equilibrium density and maximum
 reproductive rate, and these estimates were used to construct models expressing
 nematode Pf across a range of initial densities. Many of these models were
 robust, encompassing a range of sites, season, crop cultivars, and planting
 dates. Quadratic models derived from pooled field data provided an alternative
 method for expressing Pf as a function of Pi.
 
 
 278                                                    NAL Call. No.: QL461.G4
 Population parameters and probing behavior of cowpea aphid (Homoptera:
 Aphididae), on preferred and non-preferred host cover crops.
 Kaaheh, W.; Dutcher, J.D.
 Griffin, Ga. : Georgia Entomological Society; 1993 Apr.
 Journal of entomological science v. 28 (2): p. 145-155; 1993 Apr.  Includes
 references.
 
 Language:  English
 
 Descriptors: Vigna unguiculata; Sesbania exaltata; Indigofera hirsuta; Vicia
 villosa; Trifolium incarnatum; Secale cereale; Aphis craccivora; Fecundity;
 Population density; Host preferences
 
 
 279                                                      NAL Call. No.: S1.S68
 Potassium condition of drained sward podzolic, sandy loam, gleyey soil.
 Zavalin, A.A.
 New York, N.Y. : Allerton Press; 1990.
 Soviet agricultural sciences (2): p. 18-21; 1990.  Translated from: Doklady
 Vsesoyuznoi Akademii Sel'skokhozyaistvennykh Nauk Im. V.I. Lenina, No. 2, 1990,
 p. 18-22. (20 AK1).  Includes references.
 
 Language:  English; Russian
 
 Descriptors: U.S.S.R.in europe; Rsfsr; Horizons; Nutrient balance; Potassium;
 Dernopodzolic soils; Sandy loam soils; Gley soils; Rotations; Solanum
 tuberosum; Hordeum vulgare; Trifolium pratense; Secale cereale; Crop yield;
 Fertilizers; Application rates
 
 
 280                                                  NAL Call. No.: S539.5.J68
 Potassium fertilization of doublecropped wheat and soybeans under two tillage
 systems.
 Evanylo, G.K.
 Madison, Wis. : American Society of Agronomy; 1991 Oct.
 Journal of production agriculture v. 4 (4): p. 555-560; 1991 Oct.  Includes
 references.
 
 Language:  English
 
 Descriptors: Virginia; Delaware; Maryland; Glycine max; Triticum aestivum;
 Rotations; Double cropping; Coastal plain soils; Sandy soils; Coarse textured
 soils; Argillic horizons; Potassium; Tillage; No-tillage; Potassium chloride;
 Application rates; Application date; Temporal variation; Planting; Crop growth
 stage; Crop yield; Nutrient availability; Leaching; Movement in soil; Nutrient
 uptake; Soil testing; Plant analysis; Nutrient content; Precipitation; Soil
 depth; Soil water content
 
 
 281                                                     NAL Call. No.: 4 AM34P
 Potassium in two humid tropical Ultisols under a corn and soybean cropping
 system. I. Management.
 Cox, F.R.; Uribe, E.
 Madison, Wis. : American Society of Agronomy; 1992 May23.
 Agronomy journal v. 84 (3): p. 480-484; 1992 May23.  Includes references.
 
 Language:  English
 
 Descriptors: Peru; Zea mays; Glycine max; Soil chemistry; Plant analysis;
 Potassium; Potassium fertilizers; Ultisols; Application rates; Cropping
 systems; Fertilizer requirement determination; Crop yield; Humid tropics
 
 Abstract:  Sub-optimum soil K levels often limit corn (Zea mays L.) and soybean
 [Glycine mar (L.) Merr.] production in humid tropical Ultisols. The objectives
 of this study were to determine soil and plant critical levels of K and optimum
 rates of K fertilization for corn and soybean grown in the Amazon Basin of
 Peru. Two field experiments were conducted on Typic Paleudults, a loam and a
 sandy loam. Five K rates, ranging from 0 to 120 kg ha-1, were broadcast and
 incorporated prior to planting the first crop of a corn, corn, soybean rotation
 at both sites. At the loam site, K treatments were reapplied at the end of this
 rotation and three more corn crops grown. The corn stover was returned while
 the soybean stover was removed. Critical exchangeable K levels for corn were
 110 kg ha-1 on the loam and 90 kg ha-1 on the sandy loam, while for soybean it
 was 75 kg ha-1 for both soils. The critical levels of K in plant tissue at
 flowering were 13 g kg-1 in corn and 12 g kg-1 in soybean. Soybean seemed to
 lower exchangeable K to where K was released from non-exchangeable sources. An
 annual cropping system of corn and soybean with an intervening cover crop
 during the rainy season is proposed for the region. Potassium fertilization is
 recommended only prior to growing corn at kg ha-1 on a loam and 60 kg ha-1 on a
 sandy loam.
 
 
 282                                                     NAL Call. No.: 4 AM34P
 Potassium in two humid tropical ultisols under a corn and soybean cropping
 system. II. Dynamics.
 Cox, F.R.; Uribe, E.
 Madison, Wis. : American Society of Agronomy; 1992 May23.
 Agronomy journal v. 84 (3): p. 485-489; 1992 May23.  Includes references.
 
 Language:  English
 
 Descriptors: Peru; Potassium fertilizers; Zea mays; Glycine max; Application
 rates; Cropping systems; Ultisols; Soil chemistry; Potassium; Dynamics; Loam
 soils; Sandy loam soils; Humid tropics
 
 Abstract:  Understanding the dynamics of soil K is important for the
 formulation a sound fertilizer management strategy. Two experiments were
 conducted to determine the behavior of K in the soil after fertilization. Five
 rates of K (0 to 120 kg ha-1) were applied to two Typic Paleudults, a loam and
 a sandy loam, in the Peruvian Amazon Basin. A three-crop rotation of corn (Zea
 mays L.), corn, and soybean [Glycine max (L.) Merr.] was planted at each site.
 Three additional crops of corn were grown at the loam site. Potassium rates
 were applied only to the first crop of each three-crop cycle. The corn stover
 was returned, while the soybean stover was removed. Soil samples were taken at
 germination, flowering, and harvest of each crop at 20-cm depth intervals to 60
 cm in the loam and 80 cm in the sandy loom. Soil K was extracted with NaHCO3,
 NH4OAc, and concentrated H2SO4. Topsoil exchangeable K increased markedly with
 K addition, either as fertilizer or as stover, but rapidly decreased during
 cropping. Changes in the exchangeable pool were characterized with an
 exponential model. Increases in exchangeable K below 20 cm were of minor
 significance for the loam. For the sandy loam, however, subsoil exchangeable K
 was significantly increased to 60 cm. Evidences of K fixation and release were
 detected in the loam where the topsoil non-exchangeable pod peaked after K
 additions and decreased during cropping. There was no evidence of fixation in
 the sandy loam. These differences suggest that higher K rates can be applied to
 the finer textured soils and there is less risk of loss of K from the rooting
 zone.
 
 
 283                                                    NAL Call. No.: SB249.N6
 Potassium requirements for cotton following alfalfa.
 Mullins, G.L.; Burmester, C.H.
 Memphis, Tenn. : National Cotton Council of America; 1990.
 Proceedings - Beltwide Cotton Production Research Conferences. p. 484-485;
 1990.  Meeting held January 9-14, 1990, Las Vegas, Nevada.  Includes
 references.
 
 Language:  English
 
 Descriptors: Gossypium hirsutum; Medicago sativa; Potassium; Nutrient
 requirements; Rotations; Nutrient availability; Crop yield
 
 
 284                                                     NAL Call. No.: 4 AM34P
 Potassium uptake and recovery by an upland rice-soybean rotation on an Oxisol.
 Gill, D.W.; Kamprath, E.J.
 Madison, Wis. : American Society of Agronomy; 1990 Mar.
 Agronomy journal v. 82 (2): p. 329-333; 1990 Mar.  Includes references.
 
 Language:  English
 
 Descriptors: Sumatra; Oryza sativa; Glycine max; Upland rice; Rotations;
 Oxisols; Acid soils; Nutrient availability; Potassium fertilizers; Nutrient
 removal by plants; Fertilizer requirement determinatio
 
 Abstract:  A major limitation to improved crop growth on many acid Oxisols is
 low K availability. A field experiment was conducted in West Sumatra to study
 the effects of K fertilization of an Oxisol under three levels of lime (0.375,
 2.25 an 5 t ha-1) on K accumulation of a yearly upland rice (Oryza sativa L.)-
 soybean (Glycine max L. Merr.) rotation where all above-ground residue was
 removed. Six K treatments supplied 0 to 240 kg K ha-1 to each crop and lime
 treatment. Potassium fertilization increased grain yields of rice and soybean
 and K content of grain and stover of both crops. With both crops a large
 proportion of the K was present in the stover. Liming had no effect on K
 accumulation of rice grain; an inconsistent effect on K accumulation in rice
 straw; and significantly increased the K content of soybean grain and stover.
 Upland rice was very efficient in utilizing K applied to that crop as well as
 residual soil K from previous fertilization. When K rate was greater than 100
 kg ha-1 per crop appreciable amounts of K could not be accounted for indicating
 that the K was lost by leaching. Increases in exchangeable K with K
 fertilization only occurred in the 0- to 30-cm depth.
 
 
 285                                           NAL Call. No.: MeUUniv. 1991 T62
 Potato available nitrogen from barley/legume underseedings and reduced
 tillage/ridge tillage potatoes..  PLANT AND SOIL SCIENCES - 1991
 Tindall, Timothy Todd, Orono, Me.,; 1991.
 ix, 155 leaves : ill. ; 28 cm.  Includes vita.  Bibliography: leaves 148-154.
 
 Language:  English
 
 Descriptors: Potatoes; Soils; Companion planting; Crop rotation
 
 
 286                                                   NAL Call. No.: 75.8 P842
 Potato production and incidence of Verticillium dahliae following rotation to
 nonhost crops and soil fumigation in the state of Washington.
 Easton, G.D.; Nagle, M.E.; Seymour, M.D.
 Orono, Me. : Potato Association of America; 1992 Aug.
 American potato journal v. 69 (8): p. 489-502; 1992 Aug.  Includes references.
 
 Language:  English
 
 Descriptors: Washington; Solanum tuberosum; Verticillium dahliae; Disease
 prevalence; Incidence; Plant disease control; Cultural control; Rotations; Soil
 fumigation; Hosts of plant diseases; Triticum aestivum; Pisum sativum; Sorghum
 sudanense; Crop yield; Tubers; Crop quality; Specific gravity; Inoculum density
 
 
 287                                                     NAL Call. No.: 4 AM34P
 Potato response to legume and fertilizer nitrogen sources.
 Griffin, T.S.; Hesterman, O.B.
 Madison, Wis. : American Society of Agronomy; 1991 Nov.
 Agronomy journal v. 83 (6): p. 1004-1012; 1991 Nov.  Includes references.
 
 Language:  English
 
 Descriptors: Michigan; Solanum tuberosum; Rotations; Lotus corniculatus;
 Trifolium pratense; Melilotus; Vicia villosa; Zea mays; Green manures; Hay;
 Nitrogen fertilizers; Application rates; Crop yield; Tubers; Nitrogen content;
 Plant composition; Nutrient uptake; Nitrogen
 
 Abstract:  Production of potato (Solanum tuberosum L.) in rotation with an N2-
 fixing legume requires better information on the N contribution from the legume
 and on management of N fertilizer following a legume. Objectives of this
 research were to: (i) quantify N accumulation by legumes grown as either green
 manure or hay; and (ii) evaluate the vine and tuber yield response of a
 subsequent potato crop to legume and fertilizer N. We established rotations at
 two Michigan locations in 1987 on McBride sandy loam (coarse-loamy, mixed,
 frigid Alfic Fragiothods) and Oshtemo sandy loam (coarse-loamy, mixed, mesic
 Typic Hapludalfs). First-year crops included: alfalfa (Medicago sativa L.),
 birdsfoot trefoil (Lotus corniculatus L.), and red clover (Trifolium pratense
 L.) grown as both green manure (0 harvests) and bay (two or three seeding-year
 harvests); non-dormant 'Nitro' alfalfa hay; sweetclover (Melilotus spp.) and
 hairy vetch (Vicia villosa Roth) green manures; corn (Zea mays L.); fallow; and
 potato. The second-year crop was potato, fertilized with 0, 75, 150, or 225 kg
 N ha-1. Plowdown N yield [PDN = fall(herbage + root)N + spring herbage N] of
 legumes ranged from 33 (fall-seeded hairy vetch) to 238 kg N ha-1
 (sweetclover), with the PDN yield of alfalfa, red clover, sweetclover, and
 spring-seeded hairy vetch generally exceeding 150 kg ha-1. Seeding-year harvest
 of legumes tended to have little effect on PDN yield, compared to a green
 manure crop of the same species. Potato vine dry matter and N content late in
 the season were 61 to 100 and 75 to 145% higher, respectively, following
 legumes than following non-legumes, but total and marketable tuber yields were
 not affected by rotation at either location. Fertilizer N rate increased total
 marketable, and cull tuber yield at MRF, with optimum N rates of about 120 and
 170 kg ha-1 for marketable and total tuber yield, respectively. Nitrogen rate
 had no effect on tuber yield at KBS, suggesting that moisture, not available N,
 limited t
 
 
 288                                                  NAL Call. No.: S542.A8A34
 Potential of biological and chemical control of bacterial wilt.
 Hartman, G.L.; Hong, W.F.; Hanudin; Hayward, A.C.
 Canberra, A.C.T. : Australian Centre for International Agricultural Research,
 1985-; 1993.
 ACIAR proceedings (45): p. 322-326; 1993.  In the series analytic: Bacterial
 wilt / edited by G.L. Hartman and A.C. Hayward.  Meeting held on October
 28-31, 1992, Kaohsiung, Taiwan.  Includes references.
 
 Language:  English
 
 Descriptors: Lycopersicon esculentum; Pseudomonas solanacearum; Wilts; Plant
 disease control; Biological competition; Rhizosphere; Microbial pesticides;
 Pseudomonas gladioli; Pseudomonas cepacia; Pseudomonas fluorescens; Soil
 inoculation; Bactericides; Green manures; Crotalaria; Pig slurry; Inorganic
 salts
 
 
 289                                                   NAL Call. No.: S605.5.B5
 Potential of green manure species in recycling nitrogen, phosphorus and
 potassium.
 Atallah, T.; Lopez-Real, J.M.
 Oxon : A B Academic Publishers; 1991.
 Biological agriculture and horticulture : an international journal v. 8 (1): p.
 53-65; 1991.  Includes references.
 
 Language:  English
 
 Descriptors: Green manures; Legumes; Plants; Nutrients; Recycling; Nitrogen;
 Phosphorus; Potassium; Carbon; Carbon-nitrogen ratio; Nutrient uptake; Nutrient
 content; Dry matter accumulation; Biomass production; Growth rate; Losses from
 soil systems; Cover crops; Nutrient availability
 
 
 290                                                      NAL Call. No.: HD1.A3
 Predictability of grain sorghum and maize yield grown after soybean over a
 range of environments.
 Clegg, M.D.
 Essex : Elsevier Applied Science Publishers; 1992.
 Agricultural systems v. 39 (1): p. 25-31; 1992.  Includes references.
 
 Language:  English
 
 Descriptors: Nebraska; Glycine max; Sorghum bicolor; Zea mays; Crop yield;
 Rotations; Crop production; Linear models; Continuous cropping; Predicted
 difference
 
 
 291                                                   NAL Call. No.: SB610.W39
 Preplant-postemergence herbicides for legume cover-crop control in minimum
 tillage systems.
 Griffin, J.L.; Dabney, S.M.
 Champaign, Ill. : The Society; 1990 Apr.
 Weed technology : a journal of the Weed Science Society of America v. 4 (2): p.
 332-336; 1990 Apr.  Includes references.
 
 Language:  English
 
 Descriptors: Sorghum bicolor; Glycine max; No-tillage; Cover crops; Trifolium
 incarnatum; Trifolium subterraneum; Vicia villosa; Chemical control; Paraquat;
 Glyphosate; Herbicides; Application rates; Application date; Growth stages;
 Crop yield; Grain; High volume spraying; Low volume spraying
 
 
 292                                                     NAL Call. No.: 450 C16
 Previous legumes and N fertilizer effects on mineral concentration and uptake
 by forage corn.
 Pare, T.; Chalifour, F.P.; Bourassa, J.; Antoun, H.
 Ottawa : Agricultural Institute of Canada; 1993 Apr.
 Canadian journal of plant science; Revue canadienne de phytotechnie v. 73 (2):
 p. 461-476; 1993 Apr.  Includes references.
 
 Language:  English
 
 Descriptors: Zea mays; Vicia faba; Glycine max; Rotations; Sequential cropping;
 Nitrogen fertilizers; Application rates; Nutrient availability; Nutrient
 uptake; Mineral uptake; Nutrient content; Mineral content; Nitrogen content;
 Nutrient nutrient interactions
 
 
 293                                                  NAL Call. No.: S539.5.J68
 Producing no-till cereal or corn following alfalfa on furrow-irrigated land.
 Carter, D.L.; Berg, R.D.; Sanders, B.J.
 Madison, Wis. : American Society of Agronomy; 1991 Apr.
 Journal of production agriculture v. 4 (2): p. 174-179; 1991 Apr.  Includes
 references.
 
 Language:  English
 
 Descriptors: Idaho; Medicago sativa; Triticum aestivum; Zea mays; Hordeum
 vulgare; Winter wheat; Cropping systems; Rotations; No-tillage; Tillage; Furrow
 irrigation; Decomposition; Mineralization; Nitrogen; Nutrient availability;
 Nitrate nitrogen; Leaching; Production costs; Crop yield; Returns
 
 
 294                                                    NAL Call. No.: 56.8 SO3
 Production and persistence of soil enzymes with repeated addition of organic
 residues.
 Martens, D.A.; Johanson, J.B.; Frankenberger, W.T. Jr
 Baltimore, Md. : Williams & Wilkins; 1992 Jan.
 Soil science v. 153 (1): p. 53-61; 1992 Jan.  Includes references.
 
 Language:  English
 
 Descriptors: Coarse textured soils; Loam soils; Soil enzymes; Enzyme activity;
 Temporal variation; Soil treatment; Poultry manure; Sewage sludge; Barley
 straw; Hordeum vulgare; Medicago sativa; Green manures; Soil flora; Humus; Soil
 structure; Soil physical properties; Physicochemical properties; Incorporation;
 Decomposition; Carbon cycle; Nitrogen cycle; Phosphorus; Sulfur; Cycling;
 Persistence
 
 
 295                                                    NAL Call. No.: QH540.J6
 Productivity of clay tailings from phosphate mining. III. Grain crops.
 Mislevy, P.; Blue, W.G.; Roessler, C.E.; Martin, F.G.
 Madison, Wis. : American Society of Agronomy; 1991 Oct.
 Journal of environmental quality v. 20 (4): p. 788-794; 1991 Oct.  Includes
 references.
 
 Language:  English
 
 Descriptors: Florida; Zea mays; Helianthus annuus; Sorghum bicolor; Glycine
 max; Mine tailings; Phosphatic clay; Soil amendments; Crop yield; Dry matter
 accumulation; Rotations; Nutrient content; Mineral content; Radium; Nutrient
 availability; Forage; Grain; Protein content; In vitro digestibility
 
 Abstract:  Phosphatic clay is a waste product from the Florida phosphate mining
 industry presently totaling 41000 ha. These clays contain no phytotoxic
 materials, are high in most plant nutrients, and 226Ra and average about 460 g
 moisture per kilogram. A split-plot field experiment was conducted to study
 forage and grain yield, forage quality, plant nutrient concentrations, changes
 in soil nutrients, and 226Ra contents of four grain crops in various rotations.
 The crop rotations (i) corn (Zea mays L. 'Jacques 247')-sunflower (Helianthus
 annuus L. 'Cargill 205'), (ii) sunflower-grain sorghum (Sorghum bicolor L.
 Moench 'Northrup King Savanna 5'), (iii) soybean (Glycine max L. Merr.
 'Williams 80')-grain sorghum, and (iv) grain sorghum-soybean ('University of
 Florida V-1') were grown on a dry phosphatic clay with and without a 50-mm
 surface layer of quartz-sand tailings. Nitrogen was the only fertilizer element
 applied. Results show that corn and grain sorghum produced highest (P < 0.05)
 forage yields (15.7 and 13.4 Mg ha-1) and highest grain yields (8955 and 4302
 kg ha-1 per harvest, respectively. Soybean harvested for forage (Crop 1)
 contained the highest crude protein (217 g kg-1) and in vitro organic matter
 digestibility (736 g kg-1). Concentrations of P, K, Ca, Mg, and Fe in most of
 the forages were adequate for the diets of beef cattle (Bos taurus), while
 those of Mn, Cu, and Zn were low. Mehlich I-extractable soil P (1601 mg kg-1),
 Ca (4696 mg kg-1), and Mg (1173 mg kg-1) were considered very high and changed
 little over the 4-yr production period. Application of 50 mm of sand tailings
 tended to increase (P < 0.05) Mehlich I-extractable P, Ca, Mn, Cu, Zn, and Fe.
 Radium-226 concentration in the forage of all grain crops averaged 8.5 Bq kg-1,
 which was about 17 times higher than that in the grain (0.4958 Bq kg-1) of the
 same crops. Concentrations of 226Ra in the forage (8.288 Bq kg-1) and grain
 (0.6771 Bq kg-1 were 1.1% and 0.09% of the concentration in clay (761 Bq kg-1
 
 
 296                                                     NAL Call. No.: 450 C16
 Productivity, water use and nitrogen fixation of annual-legume green-manure
 crops in the Dark Brown soil zone of Saskatchewan.
 Townley-Smith, L.; Slinkard, A.E.; Bailey, L.D.; Biederbeck, V.O.; Rice, W.A.
 Ottawa : Agricultural Institute of Canada; 1993 Jan.
 Canadian journal of plant science; Revue canadienne de phytotechnie v. 73 (1):
 p. 139-148; 1993 Jan.  Includes references.
 
 Language:  English
 
 Descriptors: Saskatchewan; Vicia faba; Lens culinaris; Lathyrus tingitanus;
 Medicago sativa; Pisum sativum; Nitrogen fixation; Plant water relations; Soil
 water; Water use; Crop production; Dry matter accumulation; Green manures
 
 
 297                                                NAL Call. No.: S494.5.S86S8
 Profitability of a resource-conserving crop rotation: an analysis for a
 central Kansas farm.
 Herbel, K.L.; Williams, J.R.
 Binghamton, NY : Food Products Press, c1990-; 1992.
 Journal of sustainable agriculture v. 2 (4): p. 31-45; 1992.  Includes
 references.
 
 Language:  English
 
 Descriptors: Medicago sativa; Rotations; Returns; Profitability; Farm planning;
 Agricultural policy
 
 
 298                                                  NAL Call. No.: S539.5.J68
 Profitability of no-tillage corn following a hairy vetch cover crop.
 Hanson, J.C.; Lichtenberg, E.; Decker, A.M.; Clark, A.J.
 Madison, WI : American Society of Agronomy, c1987-; 1993 Jul.
 Journal of production agriculture v. 6 (3): p. 432-437; 1993 Jul.  Includes
 references.
 
 Language:  English
 
 Descriptors: Maryland; Cabt; Zea mays; No-tillage; Cover crops; Vicia villosa;
 Triticum aestivum; Winter wheat; Fallow; Rotations; Comparisons; Crop yield;
 Profitability
 
 
 299                                                   NAL Call. No.: QL461.I57
 Prospects for cultural and biological control of cowpea pests.
 Ezueh, M.I.
 Nairobi, Kenya : ICIPE Science Press; 1991.
 Insect science and its application v. 12 (5/6): p. 585-592; 1991.  Special
 issue: Aspects of pest management in relation to agricultural production and
 environmental conservation in Africa / edited by A.M. Alghali, N.K. Maniania,
 Mbaye Ndoye, and Z.M. Nyiira.  Includes references.
 
 Language:  English
 
 Descriptors: Nigeria; Vigna unguiculata; Insect pests; Biological control;
 Cultural control; Harvesting date; Natural enemies; Planting date; Parasites of
 insect pests; Predators of insect pests; Weed control
 
 Abstract:  Insect pest problems on cowpeas can be reduced by use of strategies
 which involve ecological manipulations. These include crop diversification
 (mixed cropping, etc.), alteration or planting dates, crop rotation, trap-
 cropping and weed control. The merits of these cultural methods of pest control
 are discussed. The status of biological control of cowpea pests is still low
 but promising. The crop is an annual and therefore offers very limited
 possibilities for the application of the classical biological control
 techniques. However, a large number of parasitic Hymenoptera, Diptera and
 predatory Hemiptera, notably Reduviids have been identified in the cowpea
 ecosystem. Ecological studies of some of these have been carried out and levels
 or parasitism determined in a few cases, but their significance in the dynamics
 of cowpea pest populations have not been fully established. It is however known
 that conservation of parasites and predators in their wild environment is one
 of the traditional biological control methods. Therefore, a rationalized
 pesticide programme for the control of cowpea pests should aim at preventing
 hazards to their natural enemies so as to increase their biocontrol efficiency.
 
 
 300                                              NAL Call. No.: SB950.3.A8P535
 Purity study of imported leguminous cover crops.
 Tasrif, A.; Sahid, I.B.; Sastroutomo, S.S.; Latiff, A.
 Victoria : R.G. Richardson; 1991.
 Plant protection quarterly v. 6 (4): p. 190-193; 1991.  Includes references.
 
 Language:  English
 
 Descriptors: Malaysia; Oil palms; Plantations; Rubber plants; Cover crops;
 Pueraria; Calopogonium caeruleum; Calopogonium mucunoides; Centrosema
 pubescens; Mucuna cochinchinensis; Seed quality; Seed purity; Weeds; Seeds;
 Viability; Importation
 
 
 301                                                      NAL Call. No.: S1.N32
 Put bean fields to bed for winter.
 Hofstetter, B.
 Emmaus, Pa. : Rodale Institute; 1991 Sep.
 The New farm v. 13 (6): p. 34; 1991 Sep.
 
 Language:  English
 
 Descriptors: Glycine max; Cover crops; Oversowing
 
 
 302                                                     NAL Call. No.: 450 C16
 Quality effects of pulses on subsequent cereal crops in the northern prairies.
 Wright, A.T.
 Ottawa : Agricultural Institute of Canada; 1990 Oct.
 Canadian journal of plant science; Revue canadienne de phytotechnie v. 70 (4):
 p. 1013-1021; 1990 Oct.  Includes references.
 
 Language:  English
 
 Descriptors: Saskatchewan; Triticum aestivum; Hordeum vulgare; Vicia faba; Lens
 culinaris; Pisum sativum; Rotations; Sequential cropping; Tillage; Seed
 quality; Seed size; Seed weight; Kernels; Plant proteins; Chemical composition;
 Nitrogen fertilizers
 
 
 303                                                     NAL Call. No.: 4 AM34P
 Quantifying the nitrogen contribution from alfalfa to soil and two succeeding
 crops using nitrogen-15.
 Harris, G.H.; Hesterman, O.B.
 Madison, Wis. : American Society of Agronomy; 1990 Jan.
 Agronomy journal v. 82 (1): p. 129-134; 1990 Jan.  Includes references.
 
 Language:  English
 
 Descriptors: Michigan; Medicago sativa; Rotations; Zea mays; Hordeum vulgare;
 Nitrogen recovery; Nitrogen residual effects; Radioactive tracers; Duration;
 Nitrogen content; Microbial activities; Nutrient removal by plants; Nitrogen
 uptake
 
 Abstract:  With the current interest in sustainable agricultural systems, the
 use of legumes is crop rotations to provide N to subsequent crops is
 increasing. The objective of this study was to quantify the N contribution from
 different alfalfa (Medicago sativa L.) plant parts to a subsequent corn (Zea
 mays L.) crop, various soil fractions, and a 2nd yr spring barley (Hordeum
 vulgare L.) crop. The study was conducted at two field locations in Michigan,
 on a Capac loam (fine-loamy, mixed, mesic, Aeric Ochraqualf) in East Lansing
 (EL) and on an Oshtemo sandy loam (coarse-loamy, mixed, mesic, Typic Hapludalf)
 at the Kellogg Biological Station (KBS) in Hickory Corners. Alfalfa shoots and
 roots/crowns labeled with 15N were applied separately to microplots in Fall
 1985 and Spring 1986 at a rate equivalent to 112 kg N ha-1. Corn was harvested
 and soil was sampled from all microplots in Fall 1986 and analyzed for 15N.
 Corn recovered 17 and 25% of the alfalfa-15N applied to the loam and sandy loam
 soils at EL and KBS, respectively. Alfalfa-15N remaining in sell averaged 46%
 of the initial input for both locations. Most (96%) of the alfalfa-15N
 remaining in soil was recovered in the organic fraction, with microbial biomass
 accounting for 18% of this recovery. More 15N was recovered by corn and in soil
 from alfalfa shoots than roots/crowns at both locations, and from spring-
 incorporated than fall-incorporated plant material on the loam soil. Only 1% of
 the alfalfa-15N from the original application was recovered by a 2nd yr spring
 barley crop at both locations.
 
 
 304                                                  NAL Call. No.: S605.5.A43
 Rainfall and previous crop effects on crop yields.
 Peterson, T.A.; Shapiro, C.A.; Flowerday, A.D.
 Greenbelt, Md. : Institute for Alternative Agriculture; 1990.
 American journal of alternative agriculture v. 5 (1): p. 33-37; 1990.
 Includes references.
 
 Language:  English
 
 Descriptors: Zea mays; Glycine max; Sorghum bicolor; Rain; Crop yield;
 Rotations; Nitrogen fertilizers
 
 
 305                                                  NAL Call. No.: QL461.E532
 Rates of increase and probing behavior of Acyrthosiphon pisum (Homoptera:
 Aphididae) on preferred and nonpreferred host cover crops.
 Kaakeh, W.; Dutcher, J.D.
 Lanham, Md. : Entomological Society of America; 1993 Oct.
 Environmental entomology v. 22 (5): p. 1016-1021; 1993 Oct.  1.
 
 Language:  English
 
 Descriptors: Cover crops; Acyrthosiphon pisum; Feeding behavior; Population
 growth; Host preferences
 
 Abstract:  Developmental time, fecundity, nymphal mortality, generation time,
 intrinsic and finite rates of increase, and days for population to double were
 compared for pea aphid, Acyrthosiphon pisum Harris, feeding on cover crop
 seedlings of sesbania, Sesbania exaltata (Rafinesque-Schmaltz) Cory; cowpea,
 Vigna unguiculata [L.] Walpers; hairy indigo, Indigofera hirsuta L.; hairy
 vetch, Vicia villosa Roth; crimson clover, Trifolium incarnatum L.; or cereal
 rye, Secale cereale L. The study was conducted under constant temperatures (15,
 20, 25, and 30 degrees C) in the laboratory. A. pisum had the shortest
 developmental, prereproductive, and generation times on V. villosa and T.
 incarnatum, followed by V. unguiculata. However, A. pisum had higher mean total
 fecundity, fecundity rate, and intrinsic and finite rates of increase on V.
 villosa and T. incarnatum than on other cover crops evaluated. Differences in
 life parameters of A. pisum were detected on the same plant species exposed to
 different temperatures. Probing behavior of individual A. pisum differed on
 various cover crops. Mean probe duration was longer on S. exaltata and I.
 hirsuta, whereas the time to start the first probe, the number of probes per 6-
 min observation period, and nonprobing duration were shorter on V. villosa and
 T. incarnatum than on other plant species evaluated.
 
 
 306                                   NAL Call. No.: KyUThesis 1992 Zourarakis
 Recovery and residuality of applied N in a corn/soft red winter wheat/double-
 crop soybean rotation grown on a well drained soil..  Recovery and residuality
 of applied N in a corn soft red winter wheat double crop soyben rotation grown
 in a well drained soil
 Zourarakis, Demetrio Periferachis, 1992; 1992.
 xx, 277 leaves : ill. ; 28 cm.  Includes vita and abstract.  Includes
 bibliographic references (l. 248-275).
 
 Language:  English
 
 Descriptors: Water, Underground; Leaching; Nitrogen fertilizers
 
 
 307                                                   NAL Call. No.: SB610.W39
 Red rice (Oryza sativa) control options in soybeans (Glycine max).
 Griffin, J.L.; Harger, T.J.
 Champaign, Ill. : The Society; 1990 Jan.
 Weed technology : a journal of the Weed Science Society of America v. 4 (1): p.
 35-38; 1990 Jan.  Includes references.
 
 Language:  English
 
 Descriptors: Louisiana; Glycine max; Herbicide recommendations; Chemical
 control; Oryza sativa; Biotypes; Herbicide rates; Alachlor; Bentazon;
 Fluazifop; Metolachlor; Herbicides; Rotations; Crop yield; Herbicide mixtures
 
 
 308                                                  NAL Call. No.: S605.5.A43
 Reduced chemical input cropping systems in the southeastern United States. I.
 Effect of rotations, green manure crops and nitrogen fertilizer on crop yields.
 King, L.D.; Buchanan, M.
 Greenbelt, MD : Henry A. Wallace Institute for Alternative Agriculture; 1993.
 American journal of alternative agriculture v. 8 (2): p. 58-77; 1993.
 Includes references.
 
 Language:  English
 
 Descriptors: Southeastern states of U.S.A.; Cabt; Rotations; Green manures;
 Crop yield; Cropping systems; Crop management; Agricultural regions;
 Agricultural chemicals; Farm inputs; Legumes; Weed control; Nitrogen
 fertilizers; Substitution
 
 Abstract:  Interest in reducing purchased chemical inputs to reduce production
 costs and avoid possible environmental damage prompted this 7-year study. Two
 management systems, current management practices (CMP) and reduced chemical
 inputs (RCI), were evaluated for four crop sequences from 1985 through 1992:
 continuous grain sorghum; continuous corn; a 2-year rotation of corn and
 double-cropped winter wheat and soybean; and a 4-year rotation of corn, winter
 wheat/soybean, corn, and red clover hay changed in 1989 to a 3-year rotation of
 corn, red clover hay, and wheat/soybean). No-till planting and recommended
 rates of fertilizer and pesticides were used in the CMP system. In the RCI
 system, N was supplied by a crimson clover green manure crop or the red clover
 in the rotation. Weed control was by chisel plowing, disking, and cultivation.
 Crimson clover top growth accumulated from 70 to 180 kg N/ha, red clover from
 77 to 130 kg N/ha. Rotating crops increased corn yield with CMP but not with
 RCI. In years, cornyields were low (less than 3000 kg/ha), corn did not respond
 to fertilizer N, and yields generally were higher with CMP than with RCI. With
 adequate rain, yield of all RCI treatments were the same as yield in CMP
 continuous corn receiving no fertilizer N. Johnsongrass competition was the
 main reason for low yields in the RCI treatments. Soybean yields were higher
 with CMP in 4 years and higher with RCI one year. Wheat and grain sorghum
 yields were higher with CMP than with RCI. A dramatic decline in johnsongrass
 in sorghum was noted in 1989, and several plots remained relatively free of
 johnsongrass through 1992. Management decisions made during the experiment
 included the degree of input reduction in RCI; whether to either end or modify
 unproductive treatments; whether to use newly available varieties and
 pesticides; whether to suspend the experiment to eliminate johnson and how to
 add new treatments while retaining the original treatments.
 
 
 309                                                    NAL Call. No.: 100 OK4M
 A reduced input approach to cabbage production: managing erosion, fertility,
 and pests.
 Roberts, B.W.; Cartwright, B.
 Stillwater, Okla. : The Station; 1990 Mar.
 Research report P - Oklahoma Agricultural Experiment Station (911): 15 p.; 1990
 Mar.  Includes references.
 
 Language:  English
 
 Descriptors: Oklahoma; Brassica oleracea var. capitata; Cultivation methods;
 Cover crops; Secale cereale; Vicia villosa; Nitrogen fertilizers; Insect pests;
 Crop damage; Insect control; Yield response functions; Insecticide application;
 Erosion control
 
 
 310                                                   NAL Call. No.: 100 AR42F
 Reduction in black root rot of cotton and the blackroot rot pathogen
 Thielaviopsis basicola by hairy vetch.
 Kendig, S.M.; Rothrock, C.S.
 Fayetteville, Ark. : The Station; 1991 May.
 Arkansas farm research - Arkansas Agricultural Experiment Station v. 40 (3): p.
 8-9; 1991 May.  Includes references.
 
 Language:  English
 
 Descriptors: Arkansas; Gossypium; Thielaviopsis basicola; Vicia villosa; Cover
 crops
 
 
 311                                                    NAL Call. No.: 23 AU792
 The relationship between incidence of infection by the take-all fungus
 (Gaeumannomyces graminis var. tritici), rainfall and yield of wheat in South
 Australia.
 Roget, D.K.; Rovira, A.D.
 East Melbourne : Commonwealth Scientific and Industrial Research Organization;
 1991.
 Australian journal of experimental agriculture v. 31 (4): p. 509-513; 1991.
 Includes references.
 
 Language:  English
 
 Descriptors: South australia; Triticum aestivum; Gaeumannomyces graminis;
 Incidence; Interactions; Pisum sativum; Rain; Rotations; Sandy soils;
 Calcareous soils; Mathematical models; Yield losses
 
 
 312                                                 NAL Call. No.: S592.7.A1S6
 Relationship of soil microbial biomass and activity with fertilization practice
 and crop yield of three ultisols.
 Insam, H.; Mitchell, C.C.; Dormaar, J.F.
 Exeter : Pergamon Press; 1991.
 Soil biology and biochemistry v. 23 (5): p. 459-464; 1991.  Includes
 references.
 
 Language:  English
 
 Descriptors: Alabama; Soil flora; Glycine max; Ultisols; Soil organic matter;
 Biomass; Respiration; Microbial activities; Soil fertility; Rotations; Carbon
 cycle; Crop yield; Correlation; Physicochemical properties
 
 Abstract:  The relationships of crop yield with soil factors such as microbial
 biomass (Cmic,), basal respiration, microbial biomass-to-organic C (Cmic:Corg)
 ratio, and metabolic quotient (qCO2) were investigated in three long-term field
 experiments in Alabama. On all three sites soybean (Glycine max L.) yield was
 significantly correlated with Cmic (r = 0.77). On the Auburn and Brewton sites,
 there were positive correlations of Cmic with the yields of sorghum, rye and
 corn. Only in a few cases, soil nutrient contents (N, P, K) were significantly
 correlated with Cmic. The Cmic:Corg ratio increased with crop yield. The data
 suggest that part of the variability of Cmic and the Cmic:Corg ratio which to a
 great extent are determined by the climatic conditions at a certain site, may
 be explained with differences in crop yield. These may in turn be caused by
 mineral fertilization. No relationship was found between basal respiration and
 soybean yield. However, the qCO2 was negatively correlated with soybean yield
 (r = -0.78) on all sites. This has important implications on agriculture: if
 more C is lost by respiration at less C input, more care must be taken to
 maintain organic C contents.
 
 
 313                                                     NAL Call. No.: 4 AM34P
 Relative nitrogen utilization by legume cover crop species at three soil
 temperatures.
 Power, J.F.; Zachariassen, J.A.
 Madison, Wis. : American Society of Agronomy; 1993 Jan.
 Journal of the American Society of Agronomy v. 85 (1): p. 134-140; 1993 Jan.
 Includes references.
 
 Language:  English
 
 Descriptors: Cover crops; Vicia faba; Vicia villosa; Melilotus alba; Trifolium
 repens; Trifolium incarnatum; Glycine max; Lespedeza stipulacea; Pisum sativum;
 Characterization; Nutrient uptake; Water use; Edaphic factors; Soil temperature
 
 Abstract:  When selecting a legume cover crop, one should know relative N-
 fixing and N uptake capabilities, as well as growth and water use
 characteristics, to identify the species best adapted to the growth period and
 soil temperatures (season) during which the cover crop is grown. We provide
 information on these characteristics for eight inoculated legume species at
 soil temperatures of 10, 20, and 30 degrees C. Plants were grown in constant-
 temperature water baths in a greenhouse for 105 d after establishment in 1.1 kg
 of Alliance silt loam (fine silty, mixed, mesic, Aridic Argiustoll) per pot.
 Plant samples were taken every 21 d for determinations of dry weight, total N
 uptake, and N2 fixed (isotope dilution method). Water use was measured daily by
 weighing. Total N uptake and N2 fixation were usually greatest for large-seeded
 annual species during the first 42 to 63 d of the experiment. At 10 degrees C
 total N uptake and N2 fixation were greatest for hairy vetch (HV), Vicia
 villosa Roth and faba bean (FB), Vicia faba L. At later sampling dates, N
 uptake and fixation for white clover (WC), Trifolium repens L., was also
 relatively high. At 20 degrees C, soybean (SB), [Glycine max (L.) Merr.]
 exhibited outstanding growth and N uptake throughout the 105 d. For the first
 42 d, FB performance also was superior to other species. At 30 degrees C, N
 uptake and fixation by SB was more than double that of any other species at all
 sampling dates. Quantity of N2 fixed per unit water used was greatest at 10
 degrees C for WC, followed closely by HV and field pea (FP) Pisum sativum L.;
 at 20 degrees C, SB followed by WC and lespedeza (LD), Lespedeza stipulacea
 Maxim.; and at 30 degrees C, LD followed by SB. Our results suggest that under
 many situations (early spring) some grain legumes, such as SB and FB, may be a
 better cover crop than many species commonly used.
 
 
 314                                                  NAL Call. No.: QH84.8.B46
 The release and plant uptake of nitrogen from some plant and animal manures.
 Rees, R.M.; Yan, L.; Ferguson, M.
 Berlin : Springer International; 1993.
 Biology and fertility of soils v. 15 (4): p. 285-293; 1993.  Includes
 references.
 
 Language:  English
 
 Descriptors: Scotland; Hordeum vulgare; Lolium perenne; Triticum aestivum;
 Animal manures; Green manures; Interactions; Mineralization; Nitrogen; Nutrient
 uptake; Pisum sativum
 
 
 315                                                 NAL Call. No.: QK898.N6N52
 Release of nitrogen during decomposition of legume tree leaves.
 Hussain, A.; Ranjha, A.M.; Sharar, M.S.; Ghaffar, A.
 Bangkok, Thailand : Thailand Institute of Scientific and Technological
 Research; 1990 Aug.
 Nitrogen fixing tree research reports v. 8: p. 51-53; 1990 Aug.  Includes
 references.
 
 Language:  English
 
 Descriptors: Pakistan; Leguminosae; Nitrogen fixing trees; Leaves; Green
 manures; Soil amendments; Crop yield; Decomposition; Nitrogen; Nutrient
 availability
 
 
 316                                                     NAL Call. No.: 4 AM34P
 Reseeding, biomass, and nitrogen content of selected winter legumes in grain
 sorghum culture.
 Boquet, D.J.; Dabney, S.M.
 Madison, Wis. : American Society of Agronomy; 1991 Jan.
 Agronomy journal v. 83 (1): p. 144-148; 1991 Jan.  Includes references.
 
 Language:  English
 
 Descriptors: Sorghum bicolor; Winter; Cover crops; Trifolium incarnatum;
 Trifolium alexandrinum; Trifolium vesiculosum; Trifolium subterraneum; Vicia;
 Cultivars; Seeds; Seed dispersal; Natural regeneration; Biomass; Growth rate;
 Nitrogen content
 
 Abstract:  Winter legumes as green manure crops in grain sorghum, Sorghum
 bicolor L. Moench, production on clay soils in the southern USA would be
 facilitated by increased knowledge of growth responses and reseeding capability
 of legume cultivars. This study evaluated 'Tibbee' crimson, Trifolium
 incarnatum L.; 'Bigbee' berseem, T. alexandrinum L.: 'Yuchi' arrowleaf, T.
 vesiculosum Savi.; and 'Woogenellup' subterranean, T. subterraneum L. clovers
 and 'Woodford' big flower vetch, Vicia grandiflora Scop., for reseeding,
 biomass and N content at seven growth termination dates (GTD): 20 and 31 March,
 10 and 21 April and 1, 13, and 22 May 1986. The field experiment was initially
 planted on 15 Oct. 1985 on a Mhoon silty clay (fine-silty, mixed, nonacid,
 thermic, Typic Fluvaquents). No legume was able to reseed the first year when
 the GTD was on or before 10 April. Crimson and subterranean clover and big
 flower vetch successfully reseeded at a GTD of 21 April. Berseem clover did not
 reseed unless the GTD was as late as 13 May, and arrowleaf clover did not
 reseed at any GTD. The legumes that reseeded the first year also reseeded a
 second year. Maximum biomass:N (kg ha-1) accumulation was 5500:150 for crimson;
 6550:190 for berseem; 6350:152 for subterranean; 6300:203 for arrowleaf
 clovers; and 2700:80 for big flower vetch. Maximum biomass and N accumulation
 occurred by the date of reseeding for all five legumes; thus, growth of these
 legumes need not extend beyond this date to realize all of the green manure
 benefits. Nitrogen content of all legumes, except big flower vetch, was
 theoretically sufficient to meet the requirements of a grain sorghum crop
 without additional N fertilizer.
 
 
 317                                                     NAL Call. No.: 4 AM34P
 Reseeding potential of crimson clover as a cover crop for no-tillage corn.
 Myers, J.L.; Wagger, M.G.
 Madison, Wis. : American Society of Agronomy; 1991 Nov.
 Agronomy journal v. 83 (6): p. 985-991; 1991 Nov.  Includes references.
 
 Language:  English
 
 Descriptors: North Carolina; Zea mays; Cover crops; No-tillage; Trifolium
 incarnatum; Reproductive performance; Seeds; Volunteer plants; Crop
 establishment; Resowing; Seed germination; Nitrogen fertilizers; Application
 rates; Crop yield; Grain; Maize silage; Nitrogen content; Nutrient uptake; Dry
 matter accumulation
 
 Abstract:  Leguminous cover crops can provide biologically fixed N to a
 subsequent corn (Zea mays L.) crop as well as erosion control and moisture
 conserving mulch, but establishment is costly and often unsuccessful. A field
 experiment was conducted for 3 yr to determine the self-reseeding potential of
 crimson clover (Trifolium incarnatum L.) and its N contribution in a no-tillage
 corn production system. Four cover crop management treatments (fallow, annual-
 seeded, volunteer-reseeded, and volunteer strip-reseeded) were combined
 factorially with four fertilizer-N rates (0, 50, 100, or 150 kg ha-1) applied
 to the subsequent corn crop. The annual-seeded, volunteer-reseeded, and
 volunteer strip-reseeded clover treatments were desiccated at corn planting.
 Averaged over 3 yr, crimson clover dry matter was 2.6, 4.2, and 3.5 Mg ha-1 for
 the annual-seeded, volunteer-reseeded, and strip-reseeded treatments,
 respectively. In 1988 and 1989, cover crop treatments produced mean corn grain
 yields of 6.0 and 6.1 Mg ha-1 compared to fallow treatment yields of 3.4 and
 4.0 Mg ha-1, respectively. This same pattern was reflected in the silage yields
 and total corn N uptake. Corn grain yields were unaffected by fertilizer-N rate
 in two out of 3 yr due to limited rainfall. Both self-reseeding treatments
 successfully reestablished each year and increased corn yields primarily by a
 mulching effect. Allowing crimson clover to mature before chemical desiccation
 or leaving strips between corn rows to produce seed appear to be effective
 methods of reseeding clover in a no-tillage corn silage production system.
 
 
 318                                                    NAL Call. No.: 79.8 W41
 Residual effects of CGA-131036 and chlorsulfuron on spring-sown rotational
 crops.
 Friesen, G.H.; Wall, D.A.
 Champaign, Ill. : Weed Science Society of America; 1991 Apr.
 Weed science v. 39 (2): p. 280-283; 1991 Apr.  Includes references.
 
 Language:  English
 
 Descriptors: Manitoba; Zea mays; Fagopyrum esculentum; Brassica napus; Linum
 usitatissimum; Pisum sativum; Helianthus annuus; Lens culinaris; Rotations;
 Persistence; Herbicide residues; Phytotoxicity; Chlorsulfuron; Triasulfuron;
 Clay loam soils; Sandy loam soils; Soil texture; Soil organic matter; Soil ph
 
 Abstract:  Response of flax, canola, field pea, sunflower, field corn, lentils,
 and common buckwheat to soil residues of CGA-131036 and chlorsulfuron applied
 at 22 g ai ha-1 was determined on two soil types at Morden, Manitoba. On a fine
 sandy loam with a pH of 7.4 and 4.5% organic matter, the length of time
 required before crops showed no phytotoxicity from CGA-131036 residues was:
 sunflower 4 yr; canola and common buckwheat 3 yr; flax 2 yr; field pea and
 field corn 1 yr. On a clay loam with a pH of 6.5 and 5.3% organic matter, the
 corresponding duration was: lentil, canola, and sunflower 3 yr; flax and field
 pea 1 yr. Chlorsulfuron residues persisted somewhat longer than CGA-131036
 residues on the sandy loam but not on the clay loam.
 
 
 319                                                     NAL Call. No.: 450 C16
 Residual effects of faba bean and soybean for a second or third succeeding
 forage-corn production.
 Pare, T.; Chalifour, F.P.; Bourassa, J.; Antoun, H.
 Ottawa : Agricultural Institute of Canada; 1993 Apr.
 Canadian journal of plant science; Revue canadienne de phytotechnie v. 73 (2):
 p. 495-507; 1993 Apr.  Includes references.
 
 Language:  English
 
 Descriptors: Zea mays; Vicia faba; Glycine max; Rotations; Sequential cropping;
 Ammonium nitrate; Application rates; Nutrient availability; Nutrient uptake;
 Nitrogen content; Crop yield; Dry matter accumulation; Nitrogen
 
 
 320                                                    NAL Call. No.: 56.9 So3
 Residual effects of interseeded hairy vetch on soil nitrate-nitrogen levels.
 Brown, R.E.; Varvel, G.E.; Shapiro, C.A.
 Madison, Wis. : Soil Science Society of America; 1993 Jan.
 Soil Science Society of America journal v. 57 (1): p. 121-124; 1993 Jan.
 Includes references.
 
 Language:  English
 
 Descriptors: Nebraska; Cabt; Zea mays; Vicia villosa; Cover crops; Residual
 effects; Ammonium nitrate; Application rates; No-tillage; Tillage; Nitrate
 nitrogen; Surface layers; Seasonal fluctuations; Nitrogen; Mineralization;
 Immobilization; Soil water content
 
 Abstract:  Increased use of winter legume cover crops has renewed interest in
 legume N mineralization patterns. This study was conducted to monitor the
 residual effect of a hairy vetch (Vicia villosa Roth) cover crop and fertilizer
 N on surface soil NO3-N concentration in no-till and conventional-till corn
 (Zea mays L.) in northeastern Nebraska on a Nora silty clay loam (fine-silty,
 mixed, mesic Udic Halplustoll). The experimental design was a split-split-split
 plot with three replicates. Main plots of conventional tillage and no-till were
 split into 0, 67, and 134 kg N ha-1 with and without hairy vetch. Soil samples
 were taken from the 0- to 7.5- and 7.5- to 15-cm depths five times during the
 1987 growing season and three times in 1988. Inclusion of a hairy vetch cover
 crop interseeded during the previous growing season increased soil NO3-N
 concentration in the surface 7.5 cm between 50 and 64 d after corn planting and
 in the 7.5- to 15-cm soil layer between 50 and 78 d after corn planting during
 1987. In 1988 (a dry growing season), hairy vetch did not significantly
 increase soil NO3-N concentration in the 0- to 7.5-cm soil layer at any
 sampling time, but did increase soil NO3-N concentration in the 7.5- to 15-cm
 depth 103 d after planting. This increase in soil NO3-N concentration occurred
 in hairy vetch plots after silking, which probably resulted in the additional N
 not being available for plant growth in 1988. Increased available N resulting
 from a legume cover crop like hairy vetch may be beneficial in N management
 programs in lower rainfall areas of the USA when amounts of precipitation are
 adequate for plant growth and N mineralization. 
 
 
 321                                                     NAL Call. No.: 4 AM34P
 Residual soil nitrogen as affected by continuous, two-year, and four-year crop
 rotation systems.
 Varvel, G.E.; Peterson, T.A.
 Madison, Wis. : American Society of Agronomy; 1990 Sep.
 Agronomy journal v. 82 (5): p. 958-962; 1990 Sep.  Includes references.
 
 Language:  English
 
 Descriptors: Nebraska; Zea mays; Glycine max; Sorghum bicolor; Avena sativa;
 Melilotus officinalis; Trifolium pratense; Rotations; Sequential cropping;
 Continuous cropping; Monoculture; Nitrogen fertilizers; Nutrient requirements;
 Application rates; Residual effects; Nitrate nitrogen; Ammonium nitrogen;
 Nutrient uptake; Nitrogen; Losses from soil systems; Crop yield; Grain
 
 Abstract:  Crop rotation systems may reduce inorganic N fertilizer needs
 because of increased N mineralization, but if that N is mineralized either too
 early or too late with respect to crop needs, it can also be susceptible to
 leaching. These concerns prompted an investigation of a long-term field study
 at Mead, NE on a Sharpsburg silty clay loam (fine, montmorillinitic, mesic,
 Typic Argiudoll) to determine effects of crop rotation and N fertilizer
 application on residual inorganic N levels to a depth of 150 cm after 4 yr. The
 study included continuous corn (Zea mays L.), continuous soybean [Glycine max
 (L.) Merr.], continuous grain sorghum [Sorghum bicolor (L.) Moench.],
 corn/soybean and grain sorghum/soybean 2-yr rotations, and corn/oat [Avena
 sativa (L.)] + clover (80% yellow sweetclover [Melilotus officinalis (L.) Lam.]
 + 20% red clover [trifolium pratense])/grain sorghum/soybean and
 corn/soybean/grain sorghum/oat + clover 4-yr rotations with three rates of N
 fertilizer application. High N application resulted in greater residual NO3-N
 concentrations for the continuous corn and grain sorghum systems than in any of
 the other cropping systems to a depth of 150 cm. Residual NO3-N concentrations
 were low (<4 mg kg-1 at depths below 30 cm) at all N application rates in
 continuous soybean and 2- and 4-yr cropping systems. Nitrogen removal by grain
 accounted for 50% of the applied N in continuous corn and grain sorghum systems
 at the low N application rate, but only 20 to 30% of the applied N at the high
 rate. Likewise, only 20 to 30% of the applied N was accounted for by N removal
 in the rotation systems at either N application rate. Indirect results from our
 study suggest immobilization by crop residues and soil organic matter, not
 leaching, is probably most responsible for apparent N losses in these cropping
 systems. Although the mechanisms were not specifically identified, our results
 do show that crop rotations can reduce inorganic N fertilizer needs and at the
 same time
 
 
 322                                            NAL Call. No.: SB87.A82W4 no.49
 Residual value of superphosphate and queensland rock phosphate measured using
 yields of serradella, burr medic and subterranean clover grown in rotation with
 wheat, and bicarbonate-extractable soil phosphorus.
 Bolland, M. D. A.
 South Perth, W.A. : Division of Plant Industries, Dept. of Agriculture,; 1992.
 33 p. : ill. ; 30 cm. (Technical report (Western Australia. Division of Plant
 Industries) ; no. 49.).  April, 1992.  Includes bibliographical references (p.
 19-20).
 
 Language:  English
 
 
 323                                                   NAL Call. No.: S631.F422
 Residual value of superphosphate for wheat and lupin grain production on a
 uniform yellow sandplain soil.
 Bolland, M.D.A.
 Dordrecht : Kluwer Academic Publishers; 1992 Jun.
 Fertilizer research v. 31 (3): p. 331-340; 1992 Jun.  Includes references.
 
 Language:  English
 
 Descriptors: Triticum aestivum; Lupins; Superphosphates; Soil analysis; Crop
 production
 
 Abstract:  In a field experiment on a sandplain soil in a low rainfall (326 mm
 per annum) Mediterranean environment of south-western Australia, the
 effectiveness of superphosphate applied in 1986 was measured in three
 subsequent years relative to freshly-applied superphosphate each year, using
 grain (seed) yields of wheat (Triticum aestivum) and lupins (Lupinus
 angustifolius). The wheat and lupins were grown in rotation and both crops were
 grown each year starting in 1986. Bicarbonate-soluble phosphorus was determined
 on soil samples taken in mid June from where the P treatment was applied in
 1986 only. These soil test values were related to the grain yields produced
 that year. For each level of superphosphate applied in 1986, soil test values
 decreased with increasing time from application. The relationship between grain
 yield and soil test values had the same general form within each year for both
 plant species, but varied between years. For both species, the effectiveness of
 superphosphate decreased by about 70-80% between the year of application and
 the first and second years after application, and by a further approximate 10%
 in the third year. The relationship between grain yield and the level of
 superphosphate applied became sigmoidal by 1989. 
 
 
 324                                                NAL Call. No.: 275.29 IO9PA
 Response of corn hybrids to nitrogen management and environment.
 Anderson, I.C.
 Ames, Iowa : The Service; 1992 Jan.
 PM - Iowa State University, Cooperative Extension Service (1467): p. 44-47;
 1992 Jan.  Includes references.
 
 Language:  English
 
 Descriptors: Iowa; Zea mays; Cultivars; Nitrogen; Fertilizers; Rotations;
 Glycine max; Crop yield
 
 
 325                                                 NAL Call. No.: QK898.N6N52
 Response of different sources of nitrogen fixing green manures on yield of
 paddy-wheat at Tarhara during 1988-89.
 Chaudhary, S.L.
 Bangkok, Thailand : Thailand Institute of Scientific and Technological
 Research; 1990 Aug.
 Nitrogen fixing tree research reports v. 8: p. 48-50; 1990 Aug.  Includes
 references.
 
 Language:  English
 
 Descriptors: Nepal; Oryza sativa; Triticum aestivum; Leguminosae; Nitrogen
 fixation; Green manures; Crop yield
 
 
 326                                                    NAL Call. No.: 79.8 W41
 Response of navy bean (Phaseolus vulgaris) and wheat (Triticum aestivum) grown
 in rotation to clomazone, imazethapyr, bentazon, and acifluorfen.
 Renner, K.A.; Powell, G.E.
 Champaign, Ill. : Weed Science Society of America; 1992 Jan.
 Weed science v. 40 (1): p. 127-133; 1992 Jan.  Includes references.
 
 Language:  English
 
 Descriptors: Phaseolus vulgaris; Rotations; Triticum aestivum; Weed control;
 Chemical control; Clomazone; Imazethapyr; Bentazone; Acifluorfen; Application
 rates; Chloramben; Eptc; Metolachlor; Pendimethalin; Phytotoxicity; Herbicide
 residues; Residual effects; Herbicide mixtures; Crop damage; Crop yield;
 Preplanting treatment; Application date; Timing; Seedling emergence
 
 Abstract:  The response of 'C-20' navy bean and 'Frankenmuth' soft white winter
 wheat grown in rotation to clomazone, imazethapyr, bentazon, and acifluorfen
 was examined. Clomazone at 560 and 430 g ai ha-1 plus 800 g ai ha-1
 pendimethalin and 2000 g ai ha-1 chloramben visibly injured navy bean in 1 of 2
 yr. However, navy bean seed moisture at harvest and yield was not reduced
 compared to the weed-free control. PPI and PRE treatments of 70 g ai ha-1
 imazethapyr did not injure navy bean or reduce yield. Imazethapyr applied POST
 at 70 g ha-1 plus nonionic surfactant visibly injured navy bean. The addition
 of urea ammonium nitrate to imazethapyr enhanced visible injury and seed
 moisture compared to nonionic surfactant alone in 1 of 2 yr. However, seed
 yield was not reduced. Seed moisture at harvest was greater following treatment
 with 430 g ai ha-1 acifluorfen plus nonionic surfactant or urea ammonium
 nitrate and 140 and 280 g ha-1 acifluorfen plus 840 g ai ha-1 bentazon in 1 of
 2 yr compared to the weed-free control, but yield was not reduced. Wheat yield
 was reduced in 2 of 2 and 1 of 2 yr by 560 g ha-1 and 430 g ha-1 clomazone,
 respectively, plus pendimethalin plus chloramben compared to the weed-free
 control. Wheat yield was not reduced by imazethapyr, bentazon, or acifluorfen.
 
 
 327                                                     NAL Call. No.: 26 T754
 Response of rainfed lowland rice to green manuring with Sesbania rostrata.
 Manguiat, I.J.; Guinto, D.F.; Perez, A.S.; Pintor, R.M.
 London : Butterworth-Heinemann; 1992 Jan.
 Tropical agriculture v. 69 (1): p. 73-77; 1992 Jan.  Includes references.
 
 Language:  English
 
 Descriptors: Philippines; Oryza sativa; Green manures; Sesbania; Yield
 components
 
 
 328                                                   NAL Call. No.: 75.8 P842
 Response of Russet Burbank and Shepody potatoes to nitrogen fertilizer in two
 cropping systems.
 Porter, G.A.; Sisson, J.A.
 Orono, Me. : Potato Association of America; 1991 Jul.
 American potato journal v. 68 (7): p. 425-443; 1991 Jul.  Includes references.
 
 Language:  English
 
 Descriptors: Maine; Solanum tuberosum; Cultivars; Nitrogen fertilizers;
 Application rates; Rotations; Trifolium pratense; Avena sativa; Triticum
 aestivum; Fertility; Nitrogen content; Soil fertility; Crop yield; Tubers;
 Size; Crop quality; Specific gravity; Varietal reactions; Fertilizer
 requirement determination
 
 
 329                                                   NAL Call. No.: SB193.F59
 Response of sorghum-sudangrass to soil amended with alfalfa or red clover
 tissues.
 Sheldon, R.J.; Johnson, K.D.; Turco, R.F.; Volenec, J.J.
 Columbia, Mo. : American Forage and Grassland Council; 1991.
 Proceedings of the Forage and Grassland Conference. p. 83-86; 1991.  Meeting
 held April 1-4, 1991, Columbia, Missouri.  Includes references.
 
 Language:  English
 
 Descriptors: Sorghum; Hybrids; Green manures; Medicago sativa; Trifolium
 pratense; Crop yield; Nitrogen content; Nutrient uptake
 
 
 330                                                    NAL Call. No.: 79.8 W41
 Response of weed to tillage and cover crop residue.
 Teasdale, J.R.; Beste, C.E.; Potts, W.E.
 Champaign, Ill. : Weed Science Society of America; 1991 Apr.
 Weed science v. 39 (2): p. 195-199; 1991 Apr.  Includes references.
 
 Language:  English
 
 Descriptors: Maryland; Zea mays; Secale cereale; Vicia villosa; Cover crops;
 Plant residues; No-tillage; Plowing; Weeds; Population density; Mollugo
 verticillata; Chenopodium album; Eleusine indica; Digitaria sanguinalis;
 Eragrostis cilianensis; Cultural weed control
 
 Abstract:  Total weed density increased after 1 yr of no-tillage and after 2 yr
 of conventional tillage in a 4-yr experiment with repeated assignment of the
 same treatment to the same plots. Large crabgrass, goosegrass, and carpetweed
 densities were higher in the no-tillage compared with the conventional-tillage
 treatment in at least 1 yr whereas common lambsquarters density was greater in
 the conventional-tillage treatment the last year of the experiment. Within the
 no-tillage treatment, rye or hairy vetch residue reduced total weed density an
 average of 78% compared to the treatment without cover crop when cover crop
 biomass exceeded 300 g m-2 and when residue covered more than 90% of the soil.
 Goosegrass, stinkgrass, and carpetweed densities were reduced by cover crop
 residue in at least 1 yr whereas large crabgrass was unaffected. Common
 lambsquarters density increased where rye was grown as a cover crop prior to
 conventional tillage. Despite differences in weed density among treatments,
 weed biomass was equivalent in all.
 
 
 331                                                  NAL Call. No.: S539.5.J68
 Risk analysis of nitrogen fertilization rates for corn and soybeans.
 Williams, J.R.; Maddux, L.D.; Barnes, P.L.; Rowell, C.P.
 Madison, Wis. : American Society of Agronomy; 1992 Apr.
 Journal of production agriculture v. 5 (2): p. 226-232; 1992 Apr.  Includes
 references.
 
 Language:  English
 
 Descriptors: Kansas; Zea mays; Glycine max; Nitrogen fertilizers; Application
 rates; Continuous cropping; Rotations; Crop yield; Returns; Variation; Risk;
 Incentives; Profitability; Irrigated conditions
 
 
 332                                                    NAL Call. No.: HD101.S6
 Risk and sustainable agriculture: a target-motad analysis of the 92-year "old
 rotation".
 Novak, J.L.; Mitchell, C.C. Jr; Crews, J.R.
 Experiment, Ga. : The Association; 1990 Jul.
 Southern journal of agricultural economics - Southern Agricultural Economics
 Association v. 22 (1): p. 145-153; 1990 Jul.  Includes references.
 
 Language:  English
 
 Descriptors: Alabama; Gossypium; Maize; Leguminosae; Glycine max; Secale
 cereale; Nitrogen fertilizers; Rotations; Agricultural research; Risks; Farm
 results; Returns; Optimization; Motad; Econometric models; University research
 
 Abstract:  Target-MOTAD was used to assess the risks and returns of sustainable
 cotton crop rotations from Auburn University's 92-year "Old Rotation." Study
 results analyze rotations of continuous cotton, with and without winter
 legumes; two years of cotton-winter legumes-corn, with and without nitrogen
 fertilization; and three years of cotton-winter legumes-corn and rye-soybeans
 double-cropped. Ten years of observations on deviations from target income were
 used to identify optimal sustainable rotation(s). Study results suggest that
 diversification in rotations, as well as in crops, results in the least risk
 for a given level of target income.
 
 
 333                                                  NAL Call. No.: 464.9 C16S
 Root lesion and root-knot nematodes associated with crops grown in rotation
 with carrots on Prince Edward Island.
 Diamond, J.; Kimpinski, J.; Gallant, C.E.
 Ottawa : Research Branch, Agriculture Canada; 1991.
 Canadian plant disease survey v. 71 (1): p. 13-15; 1991.  Includes references.
 
 Language:  English
 
 Descriptors: Prince edward Island; Daucus carota; Rotations; Hosts of plant
 pests; Trifolium pratense; Phleum pratense; Solanum tuberosum; Triticum
 aestivum; Hordeum vulgare; Lolium multiflorum; Brassica napus var.
 napobrassica; Avena sativa; Pratylenchus penetrans; Meloidogyne hapla; Plant
 parasitic nematodes; Population density; Disease surveys; Mixed infections;
 Roots; Nematode control; Cultural control
 
 
 334                                                    NAL Call. No.: 100 Al1H
 Rotating soybean cultivars maintains yields.
 Edwards, J.H.; Weaver, D.B.; Thurlow, D.L.; Eason, J.T.
 Auburn, Ala. : Agricultural Experiment Station of Auburn University, 1954-;
 1993.
 Highlights of agricultural research v. 40 (2): p. 15; 1993.
 
 Language:  English
 
 Descriptors: Alabama; Cabt; Glycine max; Cultivars; Rotations; Crop yield; Pest
 resistance; Nematoda
 
 
 335                                                NAL Call. No.: 100 SO82 (3)
 Rotation and tillage influences on yield and soil moisture.
 Rickerl, D.H.; Sorensen, D.
 Brookings, S.D. : The Station; 1991.
 TB - Agricultural Experiment Station, South Dakota State University (97): 2 p.
 (soil PR 90-25); 1991.
 
 Language:  English
 
 Descriptors: South Dakota; Zea mays; Glycine max; Tillage; Rotations; Yield
 response functions
 
 
 336                                                     NAL Call. No.: 4 AM34P
 Rotational cropping sequence affects yield of corn and soybean.
 Crookston, R.K.; Kurle, J.E.; Copeland, P.J.; Ford, J.H.; Lueschen, W.E.
 Madison, Wis. : American Society of Agronomy; 1991 Jan.
 Agronomy journal v. 83 (1): p. 108-113; 1991 Jan.  Includes references.
 
 Language:  English
 
 Descriptors: Minnesota; Zea mays; Glycine max; Rotations; Monoculture;
 Cultivars; Sequential cropping; Continuous cropping; Crop yield; Grain; Growth
 rate; Crop growth stage; Dry matter accumulation
 
 Abstract:  There are numerous reports of the beneficial effects of rotating
 corn (Zea mays L.) and soybean [Glycine max (L.) Merr.]. However, few studies
 have been specifically designed to document the important corn-soybean rotation
 effect. The objective of this study was to determine the impact of various corn
 and soybean cropping patterns on the yield of both crops. The 9-year field
 study conducted at two locations was managed for maximum production. Cropping
 sequences consisted of: continuous monoculture with the same cultivar;
 continuous monoculture with cultivars alternated; annual rotation of the two
 crops; and 1, 2, 3, 4, and 5 yr of monoculture following 5 yr of the other
 crop. Annually rotated corn yielded 10% better, and first-year corn yielded 15%
 better than corn under monoculture. Annually rotated soybean yielded 8% better,
 and first year soybean yielded 17% better than soybean under monoculture. With
 monoculture of either crop, alternating two different cultivars annually
 resulted in the same yield as continuous cropping of just one cultivar. There
 were differences in the response of the two crops to increasing years of
 monoculture: the lowest corn yield was from second year corn; the lowest
 soybean yield was from extended monoculture. Total corn dry weight was affected
 by cropping sequence but soybean dry weight was not. Our data suggest that,
 from a yield standpoint a superior cropping sequence for Minnesota would
 include at least three, and possibly more crops.
 
 
 337                                                 NAL Call. No.: 100 L93 (3)
 Rotational crops research.
 Habetz, R.J.
 Crowley, La. : The Station; 1991.
 Annual research report - Louisiana Agricultural Experiment Station (83rd): p.
 276; 1991.
 
 Language:  English
 
 Descriptors: Louisiana; Glycine max; Hibiscus cannabinus; Sorghum bicolor;
 Triticum aestivum; Rotations
 
 
 338                                                 NAL Call. No.: QL391.N4J62
 Rotations of bahiagrass and castorbean with peanut for the management of
 Meloidogyne arenaria.
 Rodriguez-Kabana, R.; Robertson, D.R.; Weaver, C.F.; Wells, L.
 Lake Alfred, Fla. : Society of Nematologists; 1991 Oct.
 Journal of nematology v. 23 (4,suppl.): p. 658-661; 1991 Oct.  Includes
 references.
 
 Language:  English
 
 Descriptors: Alabama; Arachis hypogaea; Ricinus communis; Paspalum notatum;
 Meloidogyne arenaria; Corticium rolfsii; Rotations; Aldicarb; Pest management
 
 Abstract:  The relative value of 'Hale' castorbean (Ricinus communis) and
 'Pensacola' bahiagrass (Paspalum notatum) as rotational crops for the
 management of Meloidogyne arenaria and southern blight (Sclerotium rolfsii) in
 'Florunner' peanut (Arachis hypogaea) production was studied for 3 years in a
 field experiment in southeast Alabama. Peanut following 2 years of castorbean
 (C-C-P) yielded 43% higher than monocultured peanut without nematicide. At-
 plant application of aldicarb (30.5 g a.i./100 m row in a 20-cm-wide band) to
 monocultured peanut resulted in an average 38.9% increase in yield over the 3
 years of the experiment. Peanut yield following 2 years of bahiagrass (B-B-P)
 was 36% higher than monocultured peanut without nematicide. Aldicarb
 application had no effect on southern blight, but both C-C-P and B-B-P
 rotations reduced the incidence of the disease in peanut. Juvenile populations
 of M. arenaria in soil at peanut harvest time were lower in plots with C-C-P
 than in those with the B-B-P rotation, and both rotations resulted in lower
 numbers of juveniles in soil than in the untreated monocultured peanut.
 
 
 339                                                 NAL Call. No.: QL391.N4J62
 Rotations of soybean with tropical corn and sorghum for the management of
 nematodes.
 Rodriguez-Kabana, R.; Weaver, D.B.; Robertson, D.G.; Weaver, C.F.; Carden, E.L.
 Lake Alfred, Fla. : Society of Nematologists; 1991 Oct.
 Journal of nematology v. 23 (4,suppl.): p. 662-667; 1991 Oct.  Includes
 references.
 
 Language:  English
 
 Descriptors: Alabama; Glycine max; Zea mays; Sorghum bicolor; Meloidogyne
 arenaria; Heterodera glycines; Rotations; Aldicarb; Crop yield
 
 Abstract:  The relative efficacy of rotations of soybean with sorghum and
 tropical corn for nematode management was studied for 2 years in a field
 infested with root-knot (Meloidogyne arenaria) and soybean cyst (Heterodera
 glycines, race 14) nematodes. Corn, sorghum, and soybean cv. Kirby were planted
 in 1989, and in 1990 the same areas were planted with seven soybean cultivars
 with and without at-plant application of aldicarb. Corn and sorghum did not
 support H. glycines, but significant juvenile populations of the nematode in
 soil were associated with Kirby soybean. Numbers of H. glycines and M. arenaria
 juveniles in 1990 depended on cultivar and cropping system but were little
 affected by nematicide treatment. Lowest numbers of H. glycines juveniles were
 associated with Leflore soybean and the corn-soybean rotation. Numbers of M.
 arenaria juveniles were highest with Leflore and lowest with Braxton and Brim
 soybean. The sorghum-soybean rotation resulted in slightly higher numbers of M.
 arenaria juvenile populations than soybean monoculture or the corn-soybean
 rotation. Aldicarb increased yields of some cultivars, but its use was not
 justified economically. Yields of all cultivars were from 19-287% higher in
 rotation systems than in monoculture.
 
 
 340                                                  NAL Call. No.: SB998.N4N4
 Rotations of soybean with two tropical legumes for the management of nematode
 problems.
 Rodriguez-Kabana, R.; Weaver, D.B.; Robertson, D.G.; Young, R.W.; Carden, E.L.
 Auburn, Ala. : Organization of Tropical American Nematologists; 1990 Dec.
 Nematropica v. 20 (2): p. 101-110; 1990 Dec.  Includes references.
 
 Language:  English
 
 Descriptors: Alabama; Glycine max; Aeschynomene Americana; Indigofera hirsuta;
 Meloidogyne arenaria; Heterodera glycines; Nematode control; Rotations;
 Cultivars; Crop yield
 
 
 341                                                  NAL Call. No.: S540.A2F62
 Rye or crimson clover and N fertilizer management to optimize corn ear leaf
 area, dry weight, and N concentration.
 Henderson, A.B.; Gallaher, R.N.
 Gainesville, Fla. : The Stations; 1992.
 Agronomy research report AY - Agricultural Experiment Stations, University of
 Florida (92-05): 19 p.; 1992.
 
 Language:  English
 
 Descriptors: Zea mays; Trifolium incarnatum; Secale cereale; Nitrogen
 fertilizers; Leaf area; Cover crops; Tillage; Soil management; Nitrogen
 content; Dry matter
 
 
 342                                                   NAL Call. No.: QH301.A76
 Sclerotinia on peas: implications for yield and crop rotation.
 Davis, J.M.L.
 Wellesbourne, Warwick : The Association of Applied Biologists; 1991.
 Aspects of applied biology (27): p. 351-354; 1991.  In the series analytic:
 Production and protection of legumes / edited by R.J. Froud-Williams, P.
 Gladders, M.C. Heath, J.F. Jenkyn, C.M. Knott, A. Lane and D. Pink.  Includes
 references.
 
 Language:  English
 
 Descriptors: England; Pisum sativum; Sclerotinia sclerotiorum; Fungus control;
 Iprodione; Rotations; Crop yield
 
 
 343                                                      NAL Call. No.: SB1.H6
 Screening cover crops for use in conservation tillage systems for vegetables
 following spring plowing.
 Nelson, W.A.; Kahn, B.A.; Roberts, B.W.
 Alexandria, Va. : American Society for Horticultural Science; 1991 Jul.
 HortScience v. 26 (7): p. 860-862; 1991 Jul.  Includes references.
 
 Language:  English
 
 Descriptors: Oklahoma; Cover crops; Screening; Conservation tillage;
 Vegetables; Cultivation; Herbicides; Treatment
 
 Abstract:  Several prospective cover crops were sown into 1-m2 monoculture
 plots on 9 Mar. 1987 and 10 Mar. 1988 at Bixby, Okla., and on 14 Mar. 1988 at
 Lane, Okla., after sites were plowed and fitted. Densities and dry weights of
 cover crops and weeds were determined in late April or early May of both years.
 Plots also were evaluated for degree of kill by glyphosate in 1988. Fourteen
 cover crops were screened at Bixby in 1987. Kentucky bluegrass (Poa pratensis
 L.) and three fescues Festuca rubra L., Festuca rubra L. var. commutata Gaud.-
 Beaup., and Festuca elatior L.) were eliminated from further consideration due
 to inadequate cover density and inability to suppress weeds. Screenings of the
 10 remaining covers were conducted at both locations in 1988. Annual ryegrass
 (Lolium multiflorum L.) and three small grains [rye (Secale cereale L.), barley
 (Hordeum vulgare L.), and wheat (Triticum aestivum L.)] were the most promising
 cover crops with respect to cover density, competitiveness against weeds, and
 degree of kill by glyphosate. Crimson clover (Trifolium incarnatum L.) and
 hairy vetch (Vicia villosa Roth) were the most promising legumes, but they
 generally were less satisfactory than the grassy covers in all tested aspects.
 A single application of glyphosate was ineffective in killing hairy vetch at
 both locations. Chemical name used: N-(phosphonomethyl)glycine (glyphosate).
 
 
 344                                                  NAL Call. No.: QH84.8.B46
 Seasonal fluctuations in soil microbial biomass carbon, phosphorus nand
 activity in no-till and reduced-chemical-input maize agroecosystems.
 Buchanan, M.; King, L.D.
 Berlin : Springer International; 1992 Aug.
 Biology and fertility of soils v. 13 (4): p. 211-217; 1992 Aug.  Includes
 references.
 
 Language:  English
 
 Descriptors: North Carolina; Zea mays; Soil biology; Biomass; Carbon; Legumes;
 Microbial activities; No-tillage; Phosphorus; Rotations
 
 
 345                                                    NAL Call. No.: 56.9 SO3
 Seasonal microbial biomass dynamics after addition of lentil and wheat
 residues.
 Bremer, E.; Van Kessel, C.
 Madison, Wis. : The Society; 1992 Jul.
 Soil Science Society of America journal v. 56 (4): p. 1141-1146; 1992 Jul.
 Includes references.
 
 Language:  English
 
 Descriptors: Saskatchewan; Soil flora; Biomass; Biological activity in soil;
 Crop residues; Lentils; Green manures; Wheat; Straw; Straw incorporation;
 Carbon; Nitrogen; Assimilation; Seasonal fluctuations
 
 Abstract:  The dynamics of soil microbial biomass after the addition of plant
 residues have a considerable influence on nutrient availability for plants, and
 can be quantified using the chloroform-fumigation-extraction method. The
 dynamics of microbial C and N following addition of 14C- and 15N-labeled lentil
 (Lens culinaris Medik.) green manure, lentil straw, and wheat (Triticum
 aestivum L.) straw were investigated under field conditions at a site located
 at Outlook, Saskatchewan, on a Bradwell sandy loam (Typic Boroll). Plant
 residues were incorporated into microplots on 5 Oct. 1988, and the fraction of
 added 14C and 15-N in microbial biomass was determined on four dates during the
 1989 growing season. Maximum levels of labeled and unlabeled microbial biomass
 were observed at the time of planting (8 May) in 1989. Of added 14C, 26 and 15%
 was in the microbial biomass in the green manure and straw treatments,
 respectively, on 8 May; greater microbial accumulation of green-manure 14C was
 due to a higher proportion of 14C being available rather than to a higher
 efficiency of 14C assimilation. Microbial 15N accounted for 65 to 81% of added
 residue 15N on 8 May. Plant-residue 15N was readily available to decomposer
 microorganisms from all residue types, whereas 14C was more available from
 green manure than straw. During the 1989 growing season, microbial 14C declined
 by 51 and 400/c in the green manure and straw treatments, respectively, while
 microbial 15N declined by 54% in all treatments. The decline in microbial 15N
 during the 1989 growing season was approximately five times greater than the
 amount of 15N mineralized in all sampling periods except the first for the
 green-manure treatment. The highest levels of labeled and unlabeled microbial
 biomass observed at the time of planting indicates that microbial biomass may
 reduce losses of N and other nutrients during periods of low crop demand, and
 may act as a source of nutrients during crop growth.
 
 
 346                                                     NAL Call. No.: 420 K13
 Seedcorn maggot (Diptera: Anthomyiidae) populations on Ohio soybean.
 Hammond, R.B.
 Lawrence, Kan. : The Society; 1991 Apr.
 Journal of the Kansas Entomological Society v. 64 (2): p. 216-220; 1991 Apr.
 Includes references.
 
 Language:  English
 
 Descriptors: Ohio; Glycine max; Cover crops; Incorporation; Delia platura;
 Planting date; Oviposition; Population density; Insect traps; Surveys; Crop
 damage
 
 
 347                                                    NAL Call. No.: 79.8 W41
 Seventeen years of cropping systems and tillage affect velvetleaf (Abutilon
 theophrasti) seed longevity.
 Lueschen, W.E.; Andersen, R.N.; Hoverstad, T.R.; Kanne, B.K.
 Champaign, Ill. : Weed Science Society of America; 1993 Jan.
 Weed science v. 41 (1): p. 82-86; 1993 Jan.  Includes references.
 
 Language:  English
 
 Descriptors: Abutilon theophrasti; Weed control; Continuous cropping; Fallow;
 Rotations; Tillage; No-tillage; Atrazine; Glyphosate; Seed longevity; Seed
 germination; Soil depth; Medicago sativa; Zea mays; Avena sativa
 
 Abstract:  Velvetleaf is difficult to control in corn and soybean and the seed
 can persist in soil for many years. Seven cultural and tillage practices were
 established in 1974 on a site heavily infested with velvetleaf to determine the
 time required to eradicate velvetleaf seed from the soil. A rapid decline in
 velvetleaf seed population in the top 23 cm of soil occurred during the first 5
 yr of this study. In the fifth year, the chemical fallow and continuous alfalfa
 treatments had 37 and 56% of the original velvetleaf seed population remaining,
 respectively. In the 17th year, soils in these treatments that had received no
 tillage since study initiation still contained 15 and 25% of the original
 velvetleaf seed population, respectively. Systems involving moldboard plowing
 with continuous-tillage fallow, continuous cropping of corn or oat, or an
 annual corn and soybean rotation had a more rapid decline in the velvetleaf
 seed population in soil compared to the chemical fallow and continuous alfalfa
 treatment. After 17 yr, soil in any system that had received at least one
 moldboard plowing per year still contained 1 to 3 million velvetleaf seed ha-1,
 which is only 0.8 to 2.5% of the initial viable seed population. Nearly 100% of
 the seed remaining in the soil in the 17th year for all treatments was still
 viable.
 
 
 348                                                  NAL Call. No.: 292.8 W295
 Simulating physical processes and economic behavior in saline, irrigated
 agriculture: model development.
 Lefkoff, L.J.; Gorelick, S.M.
 Washington, D.C. : American Geophysical Union; 1990 Jul.
 Water resources research v. 26 (7): p. 1359-1369. maps; 1990 Jul.  Includes
 references.
 
 Language:  English
 
 Descriptors: Colorado; Irrigation water; Saline water; Streams; Aquifers; Water
 use; Profits; Costs; Decision making; Crop mixtures; Zea mays; Medicago sativa;
 Crop yield; Simulation models; Regressions
 
 Abstract:  A model of an irrigated, saline stream-aquifer system is constructed
 to simulate economic, agronomic, and hydrologic processes. The model is applied
 to a section of the Arkansas Valley in southeastern Colorado and is used to
 examine the effect of crop-mixing strategies on long-term profits. Mixing in
 excess of crop rotation requirements provides an index of farmers' willingness
 to exchange some profit for a reduction in the risk of short-term loss. The
 model contains three components. The economic component simulates water use
 decisions that maximize annual profit for each farm, The hydrologic component
 simulates salt transport by employing regression equations that predict changes
 in groundwater salinity as a function of hydrologic conditions and water use
 decisions. The agronomic component approximates changes in corn and alfalfa
 production in response to the depth and salinity of irrigation applications.
 Results from the entire economic-hydrologic-agronomic model are consistent with
 the few historical observations available for the site.
 
 
 349                                                  NAL Call. No.: S539.5.J68
 Soil and plant nitrogen availability tests for corn following alfalfa.
 Bundy, L.G.; Andraski, T.W.
 Madison, WI : American Society of Agronomy, c1987-; 1993 Apr.
 Journal of production agriculture v. 6 (2): p. 200-206; 1993 Apr.  Includes
 references.
 
 Language:  English
 
 Descriptors: Wisconsin; Cabt; Zea mays; Medicago sativa; Fertilizer requirement
 determination; Rotations; Nitrate nitrogen; Nutrient availability; Soil
 analysis; Nutrient content; Soil depth; Seasonal variation; Air temperature;
 Rain; Nitrogen fertilizers; Application rates; Crop yield; Plant composition;
 Nitrogen content
 
 
 350                                                  NAL Call. No.: QH84.8.B46
 Soil N dynamics and N yield of barley grown on Breton loam using N from
 biological fixation or fertilizer.
 Wani, S.P.; McGill, W.B.; Robertson, J.A.
 Berlin : Springer International; 1991.
 Biology and fertility of soils v. 12 (1): p. 10-18; 1991.  Includes references.
 
 Language:  English
 
 Descriptors: Alberta; Hordeum vulgare; Continuous cropping; Rotations; Soil
 fertility; Avena sativa; Green manures; Mineralization; Nitrogen; Nitrogen
 fertilizers; Vicia faba; Site factors; Soil biology; Soil chemistry; Soil
 physical properties
 
 
 351                                                    NAL Call. No.: 56.8 So3
 Soil nitrogen mineralization indexes and corn response in crop rotations.
 Thicke, F.E.; Russelle, M.P.; Hesterman, O.B.; Sheaffer, C.C.
 Baltimore : Williams & Wilkins Co., 1916-; 1993 Nov.
 Soil science v. 156 (5): p. 322-335; 1993 Nov.  Includes references.
 
 Language:  English
 
 Descriptors: Minnesota; Cabt; Zea mays; Medicago sativa; Glycine max; Triticum
 aestivum; Fallow; Rotations; Nitrogen; Mineralization; Indexes; Crop residues;
 Incorporation; Crop yield; Grain; Nutrient uptake; Ammonium nitrate;
 Application rates; Fertilizer requirement determination; Nutrient availability;
 Models
 
 
 352                                                    NAL Call. No.: S590.C63
 Soil penetrometer resistance and bulk density relationships after long-term no
 tilage.
 Vazquez, L.; Myhre, D.L.; Hanlon, E.A.; Gallaher, R.N.
 New York, N.Y. : Marcel Dekker; 1991.
 Communications in soil science and plant analysis v. 2 (19/20): p. 2101-2117;
 1991.  Includes references.
 
 Language:  English
 
 Descriptors: Florida; Avena sativa; Glycine max; Sandy soils; Soil compaction;
 Penetrometers; Resistance to penetration; Bulk density; Measurement; Soil
 strength; Soil density; Correlation; Double cropping; Rotations; Tillage; No-
 tillage; Subsoiling; Soil depth; Soil water content; Field capacity;
 Trafficability
 
 
 353                                                    NAL Call. No.: 56.9 SO3
 Soil surface modification by biomass inputs affecting rainfall infiltration.
 Bruce, R.R.; Langdale, G.W.; West, L.T.; Miller, W.P.
 Madison, Wis. : The Society; 1992 Sep.
 Soil Science Society of America journal v. 56 (5): p. 1614-1620; 1992 Sep.
 Includes references.
 
 Language:  English
 
 Descriptors: Georgia; Glycine max; Sorghum bicolor; Trifolium incarnatum; Crop
 residues; Biomass; Incorporation; Aggregates; Stability; Soil organic matter;
 Surface layers; Surface modification; Infiltration; Soil water regimes
 
 Abstract:  The quantity, kind, and method of applying organic materials to the
 soil in crop culture are known to have a major effect on surface
 characteristics. To determine the effectiveness of selected crop biomass inputs
 on soil surface characteristics that significantly impact rainfall
 infiltration, sites on slightly, moderately, and severely eroded classes of
 Cecil-Pacolet soils (clayey, kaolinitic, thermic Typic Kanhapludults) were
 selected. On each class of erosion, soybean [Glycine max (L.) Merr.] and grain
 sorghum [Sorghum bicolor (L.) Moench] were each planted into a disk-harrowed
 seedbed following winter fallow in each of 5 yr. Grain sorghum was also no-
 till-planted into a crimson clover (Trifolium incarnatum L.) cover crop. Each
 summer crop was grown both under irrigation and natural rainfall. The average
 water stability of aggregates in the 0- to 15-mm layer of the no-till-planted
 grain sorghum into clover was 53 and 44% greater than the tilled plantings of
 grain sorghum and soybean, respectively. Only at > 0.8 kg kg-1 aggregate
 stability was correlated with soil C content. In contrast, regressions of
 water-stable soil aggregates on the natural log of cumulative stover after 5 yr
 of treatment yielded r2 values of 0.81 to 0.99. Soil-incorporated soybean
 stover was distinctly least effective in developing water-stable soil
 aggregates in the surface 1.5 cm. The effect of increased soil surface
 aggregate stability was reflected in a soil water pressure greater than -0.1
 MPa in the surface 0.5 m for a significantly greater fraction of the summer
 growing season and in increased infiltration. The infiltration rate after
 residue removal was 100% greater on the grain sorghum no-till planted into
 clover than grain sorghum planted into a tilled seedbed. The soil modifications
 that produced a very significant change in rate of infiltration were obtained
 in 4 or 5 yr by a no-till culture that provides about 12 Mg ha-1 yr-1 of
 decomposing crop residue on the soil surface. 
 
 
 354                                                  NAL Call. No.: S539.5.J68
 Soil test values and grain yields during 14 years of potassium fertilization of
 corn and soybean.
 Mallarino, A.P.; Webb, J.R.; Blackmer, A.M.
 Madison, Wis. : American Society of Agronomy; 1991 Oct.
 Journal of production agriculture v. 4 (4): p. 560-566; 1991 Oct.  Includes
 references.
 
 Language:  English
 
 Descriptors: Iowa; Glycine max; Zea mays; Rotations; Potassium fertilizers;
 Crop yield; Grain; Soil test values; Potassium; Nutrient availability; Cost
 effectiveness analysis; Profitability; Returns; Application rates; Long term
 experiments; Nutrient excesses; Nutrient deficiencies
 
 
 355                                                 NAL Call. No.: S544.3.O5O5
 Soilborne blight diseases of peanut.
 Damicone, J.P.; Melouk, H.A.
 Stillwater, Okla. : The Service; 1991 Apr.
 OSU extension facts - Cooperative Extension Service, Oklahoma State University
 (7186): 6 p.; 1991 Apr.  Includes references.
 
 Language:  English
 
 Descriptors: Oklahoma; Arachis hypogaea; Corticium rolfsii; Sclerotinia minor;
 Disease course; Disease control; Symptoms; Fungicides; Rotations; Cultural
 control; Crop yield
 
 
 356                                                  NAL Call. No.: SB998.N4N4
 Sorghum in rotation with soybean for the management of cyst and root-knot
 nematodes.
 Rodriguez-Kabana, R.; Weaver, D.B.; Robertson, D.G.; King, P.S.; Carden, E.L.
 Auburn, Ala. : Organization of Tropical American Nematologists; 1990 Dec.
 Nematropica v. 20 (2): p. 111-119; 1990 Dec.  Includes references.
 
 Language:  English
 
 Descriptors: Alabama; Glycine max; Sorghum bicolor; Heterodera glycines;
 Meloidogyne arenaria; Cultural control; Cropping systems; Nematode control;
 Rotations; Cultivars; Crop yield
 
 
 357                                                  NAL Call. No.: SB844.I6P8
 Soybean cyst nematode.
 Ferris, J.M.; Faghihi, J.; Edwards, C.R.
 West Lafayette, Ind. : The Service; 1992 Jan.
 E - Purdue University, Cooperative Extension Service v.): 4 p.; 1992 Jan.  In
 subseries: Field Crop Insects.
 
 Language:  English
 
 Descriptors: Indiana; Glycine max; Heterodera glycines; Nematode control; Life
 cycle; Rotations; Nematicides; Cultivars; Pest resistance
 
 
 358                                               NAL Call. No.: 275.29 M68EXT
 Soybean cyst nematode.
 Moore, W.F.; Fox, J.A.; Patel, M.V.
 State College, Miss. : The Service; 1991 Aug.
 Publication - Cooperative Extension Service, Mississippi State University
 (1293): 4 p.; 1991 Aug.
 
 Language:  English
 
 Descriptors: Mississippi; Glycine max; Heterodera glycines; Symptoms; Life
 cycle; Cultural methods; Rotations; Nematode control; Nematicides
 
 
 359                                                   NAL Call. No.: SB610.W39
 Soybean (Glycine max) and rotational crop tolerance to chlorimuron, clomazone,
 imazaquin, and imazethapyr.
 Krausz, R.F.; Kapusta, G.; Knake, E.L.
 Champaign, Ill. : The Society; 1992 Jan.
 Weed technology : a journal of the Weed Science Society of America v. 6 (1): p.
 77-80; 1992 Jan.  Includes references.
 
 Language:  English
 
 Descriptors: Illinois; Glycine max; Rotations; Triticum aestivum; Zea mays;
 Herbicide residues; Crop damage; Residual effects; Chlorimuron; Clomazone;
 Imazaquin; Imazethapyr; Crop yield; Tolerance
 
 
 360                                                   NAL Call. No.: SB610.W39
 Soybean (Glycine max) herbicide carryover to grain and fiber crops.
 Walsh, J.D.; DeFelice, M.S.; Sims, B.D.
 Champaign, Ill. : The Weed Science Society of America; 1993 Jul.
 Weed technology : a journal of the Weed Science Society of America v. 7 (3): p.
 625-632; 1993 Jul.  Includes references.
 
 Language:  English
 
 Descriptors: Missouri; Cabt; Triticum aestivum; Gossypium hirsutum; Zea mays;
 Sorghum bicolor; Rotations; Glycine max; Sequential cropping; Weed control;
 Chemical control; Chlorimuron; Imazaquin; Clomazone; Imazethapyr; Metribuzin;
 Herbicide mixtures; Persistence; Residual effects; Tillage; Autumn; Crop
 damage; Abiotic injuries
 
 
 361                                                     NAL Call. No.: S67.P82
 Soybean nematodes.
 Overstreet, C.; Whitam, K.; McGawley, E.C.
 Baton Rouge, La.? : The Service; 1992 May.
 Publication - Louisiana Cooperative Extension Service v.): 20 p.; 1992 May.
 
 Language:  English
 
 Descriptors: Louisiana; Glycine max; Plant parasitic nematodes; Life cycle;
 Nematode control; Varietal resistance; Rotations; Cultural control; Chemical
 control
 
 
 362                                                NAL Call. No.: S544.3.N9C46
 Soybean production.
 Berglund, D.R.; Helms, T.C.
 Fargo, N.D. : The University; 1992 Mar.
 NDSU Extension Service [publication] - North Dakota State University v.): 8 p.;
 1992 Mar.  Includes references.
 
 Language:  English
 
 Descriptors: North Dakota; Glycine max; Cultivars; Rotations; Crop yield; Seed
 quality; Seed treatment; Site preparation; Fertilizers; Spacing; Weed control;
 Harvesting
 
 
 363                                                  NAL Call. No.: S539.5.J68
 Soybean production as affected by tillage in a corn and soybean management
 system. I. Cultivar response.
 Lueschen, W.E.; Evans, S.D.; Ford, J.H.; Hoverstad, T.R.; Kanne, B.K.; Orf,
 J.H.; Staricka, J.A.; Stienstra, W.C.; Warnes, D.D.; Hicks, D.R.
 Madison, Wis. : American Society of Agronomy; 1991 Oct.
 Journal of production agriculture v. 4 (4): p. 571-579; 1991 Oct.  Includes
 references.
 
 Language:  English
 
 Descriptors: Minnesota; Glycine max; Cultivars; Zea mays; Rotations;
 Conservation tillage; No-tillage; Ridging; Plowing; Chiselling; Moldboards;
 Crop production; Performance; Crop yield; Crop density; Maturation; Lodging;
 Plant height; Seeds; Weight; Emergence; Crop residues; Temporal variation;
 Spatial variation; Spatial distribution; Climatic factors; Environmental
 factors; Soil water content; Interactions; Soil conservation; Autumn; Genotype
 environment interaction; Varietal reactions; Responses
 
 
 364                                                  NAL Call. No.: S539.5.J68
 Soybean production as affected by tillage in a corn and soybean management
 system. II. Seed treatment response.
 Lueschen, W.E.; Evans, S.D.; Ford, J.H.; Hoverstad, T.R.; Kanne, B.K.; Orf,
 J.H.; Staricka, J.A.; Steinstra, W.C.; Warnes, D.D.; Hicks, D.R.
 Madison, Wis. : American Society of Agronomy; 1991 Oct.
 Journal of production agriculture v. 4 (4): p. 580-585; 1991 Oct.  Includes
 references.
 
 Language:  English
 
 Descriptors: Minnesota; Glycine max; Cultivars; Zea mays; Rotations;
 Phytophthora; Root rots; Plant disease control; Captan; Metalaxyl; No-tillage;
 Ridging; Moldboards; Plowing; Chiselling; Seed treatment; Responses; Crop
 production; Performance; Crop yield; Crop density; Seed germination; Seedling
 emergence; Plant height; Maturation; Seeds; Weight; Seedlings; Vigor; Seed
 quality; Varietal susceptibility; Interactions; Temporal variation; Spatial
 variation
 
 
 365                                                     NAL Call. No.: 4 AM34P
 Soybean stover nitrogen affected by dinitrogen fixation and cultivars.
 Ravuri, V.; Hume, D.J.
 Madison, Wis. : American Society of Agronomy, [1949-; 1993 Mar.
 Agronomy journal v. 85 (2): p. 328-333; 1993 Mar.  Includes references.
 
 Language:  English
 
 Descriptors: Ontario; Cabt; Glycine max; Cultivars; Rotations; Soil
 inoculation; Bradyrhizobium japonicum; Nitrogen fixation; Stover; Dry matter;
 Seeds; Yields; Harvest index
 
 Abstract:  Grain legumes often are credited with leaving residual N for crops
 that follow in the rotation. This study was conducted to determine if
 increasing N2 fixation in soybean [Glycine mar (L) Merr.] would result in
 higher amounts of stover N at harvest. Eleven early-maturing cultivars
 (Maturity group 00 and 0) in 1988 and 16 in 1989 were grown with five inoculant
 strain treatments and alone as uninoculated controls. There were slight
 cultivar-by-inoculant interactions but main effects were much larger. The order
 of N2 fixtion with inoculant treatments, measured by the difference method, was
 532C or three-strain mixture > USDA 110 > CB 1809 > HH303. Dinitrogen fixation
 ranged from 60 to 125 kg ha-(1) in 1988 and from 31 to 84 in 1989. Higher N2
 fixation caused related significant (P less than or equal to 0.05) increases in
 stover dry matter and stover N yields in both years, despite concomitant
 increases in the apparent harvest index (AHI) and apparent NHI. Stover N
 concentration was not affected by increased N2 fixation in either year. In
 1988, cultivars differed only slightly in stover N content. In 1989, amounts of
 stover N in different cultivars depended on how completely N was translocated
 to seed. Over the 2 yr, amounts of N in harvestable stover of the early-
 maturing cultivars ranged from 9 to 24 kg ha-(1), averaged across inoculant
 treatments. Although stover N increased with N2 fixation in both years, the
 amount of stover N available for return to the soil was quite low.
 
 
 366                                                  NAL Call. No.: SB998.N4N4
 Soybean-peanut rotations for the management of Meloidogyne arenaria and
 Sclerotium rolfsii.
 Rodriguez-Kabana, R.; Robertson, D.G.; Wells, L.; King, P.S.
 Auburn, Ala. : Organization of Tropical American Nematologists; 1991 Dec.
 Nematropica v. 21 (2): p. 147-154; 1991 Dec.  Includes references.
 
 Language:  English
 
 Descriptors: Alabama; Glycine max; Arachis hypogaea; Meloidogyne arenaria;
 Population density; Corticium rolfsii; Aldicarb; Chemical control; Fungus
 control; Nematode control; Monoculture; Rotations; Sequential cropping
 
 
 367                                               NAL Call. No.: S561.6.A82E96
 Soybeans in rice rotation, loamy soils, flood irrigation.
 Windham, T.E.; Stuart, C.A.; Herrington, B.E. Jr
 Fayetteville, Ark.?: The Service; 1991 Nov.
 Extension technical bulletin - UA Cooperative Extension Service (153): 6 p.;
 1991 Nov.
 
 Language:  English
 
 Descriptors: Arkansas; Glycine max; Crop production; Cost analysis; Farm
 budgeting; Production costs; Loam soils; Flood irrigation
 
 
 368                                                NAL Call. No.: SB205.S7S645
 Soybeans: soybean nematode control.
 Drye, C.E.; Mueller, J.D.; Lewis, S.A.; Dickerson, O.J.
 Clemson, S.C. : The Service; 1991 Feb.
 Soybean leaflet - Cooperative Extension Service, Clemson University (2): 4 p.;
 1991 Feb.  Includes references.
 
 Language:  English
 
 Descriptors: South Carolina; Glycine max; Nematode control; Nematoda;
 Nematicides; Rotation; Cultural control; Symptoms
 
 
 369                                                     NAL Call. No.: 4 AM34P
 SOYHERB--A computer program for soybean herbicide decision making.
 Renner, K.A.; Black, J.R.
 Madison, Wis. : American Society of Agronomy; 1991 Sep.
 Agronomy journal v. 83 (5): p. 921-925; 1991 Sep.  Includes references.
 
 Language:  English
 
 Descriptors: Glycine max; Herbicides; Application methods; Weeds; Decision
 making; Weed competition; Computer software
 
 Abstract:  There has been a rapid increase in the number of herbicides and
 herbicide mixtures registered for use in soybean [Glycine max (L.) Merr.]
 production. SOYHERB is a computer program developed to assist Cooperative
 Extension Service personnel, agribusiness, farmers, and teachers in determining
 herbicide options for soybean production. Tillage practices, atrazine (6-
 chloro-N-ethyl-N'-(1-methylethyl)-1,3,5-triazine-2,4-diamine) or simazine (6-
 chloro-N,N'-diethyl-1,3,5-triazine-2,4-diamine) use in a previous corn crop,
 soil type and percentage of organic matter, soil pH, projected crop rotation
 plans, method of herbicide application, and weed species and weed pressure are
 entered by the user. SOYHERB generates herbicide programs and their cost per
 acre that provide excellent control of all weed species at the weed pressures
 indicated. Fair (80-90%) weed control options may also be generated. Additional
 screens describe control of perennial weeds, a summary of herbicide premixes,
 and a table listing the maximum height of broadleaf weeds controlled by
 postemergence herbicides. Data can be saved for future reference. A computer
 capable of running MS-DOS or PC-DOS version 2.1 or greater with a minimum of
 512K bytes of RAM is required.
 
 
 370                                                 NAL Call. No.: QL391.N4J62
 Stability and characteristics of spatial description parameters for nematode
 populations.
 Ferris, H.; Mullens, T.A.; Foord, K.E.
 Lake Alfred, Fla. : Society of Nematologists; 1990 Oct.
 Journal of nematology v. 22 (4): p. 427-439; 1990 Oct.  Includes references.
 
 Language:  English
 
 Descriptors: California; Vigna unguiculata; Gossypium hirsutum; Rotations;
 Plant parasitic nematodes; Population dynamics; Economic thresholds
 
 
 371                                                   NAL Call. No.: 56.8 J822
 Stale seedbed production of soybeans with a wheat cover crop.
 Elmore, C.D.; Wesley, R.A.; Heatherly, L.G.
 Ankeny, Iowa : Soil and Water Conservation Society of America; 1992 Mar.
 Journal of soil and water conservation v. 47 (2): p. 187-190; 1992 Mar.
 Includes references.
 
 Language:  English
 
 Descriptors: Mississippi; Glycine max; Triticum; Double cropping; Ground cover;
 Seedbeds; Clay soils
 
 
 372                                                    NAL Call. No.: S590.A48
 Stem-nodulating legume-Rhizobium symbiosis and its agronomic use in lowland
 rice.
 Ladha, J.K.; Pareek, R.P.; Becker, M.
 New York, N.Y. : Springer-Verlag; 1992.
 Advances in soil sciences v. 20: p. 147-192; 1992.  Includes references.
 
 Language:  English
 
 Descriptors: Leguminosae; Rhizobium; Symbiosis; Nitrogen fixation; Nodulation;
 Stems; Stem nodules; Cropping systems; Green manures; Oryza sativa; Reviews
 
 
 373                                                    NAL Call. No.: S601.A34
 Subterranean clover living mulch: an alternative method of weed control.
 Ilnicki, R.D.; Enache, A.J.
 Amsterdam : Elsevier; 1992 May.
 Agriculture, ecosystems and environment v. 40 (1/4): p. 249-264; 1992 May.  In
 the Special Issue: Biotic Diversity in Agroecosystems / edited by M.G.
 Paoletti and D. Pimentel. Proceedings from a symposium on Agroecology and
 Conservation Issues in Tropical and a Temperate Regions, September 26-29, 1990,
 Padova, Italy.  Includes references.
 
 Language:  English
 
 Descriptors: New Jersey; Weed control; Live mulches; Trifolium subterraneum;
 Mulches; Secale cereale; Cover crops; Zea mays; Glycine max; Cucurbita pepo;
 Brassica oleracea; Phaseolus vulgaris; Lycopersicon esculentum; Tillage;
 Minimum tillage; No-tillage; Herbicides; Weeds; Biomass production; Crop
 yield; Alternative farming
 
 
 374                                                    NAL Call. No.: 1.9 P69P
 Suitability of alfalfa, corn, oat, red clover, and snapbean as hosts for the
 potato rot nematode, Ditylenchus destructor.
 MacGuidwin, A.E.; Slack, S.A.
 St. Paul, Minn. : American Phytopathological Society; 1991 Jan.
 Plant disease v. 75 (1): p. 37-39; 1991 Jan.  Includes references.
 
 Language:  English
 
 Descriptors: Wisconsin; Medicago sativa; Trifolium pratense; Zea mays; Avena
 sativa; Phaseolus vulgaris; Solanum tuberosum; Ditylenchus destructor; Nematode
 infections; Hosts of plant pests; Rotations
 
 
 375                                                NAL Call. No.: 275.29 IO9PA
 A survey of pesticides used in Iowa crop production in 1990.
 Hartzler, R.
 Ames, Iowa : The Service; 1991 Sep.
 PM - Iowa State University, Cooperative Extension Service (1441): 11 p.; 1991
 Sep.  Includes statistical data.  Includes references.
 
 Language:  English
 
 Descriptors: Iowa; Zea mays; Glycine max; Pesticides; Herbicides; Rotations;
 Weed control; Statistics; Pest control; Crop yield; Crop production
 
 
 376                                                   NAL Call. No.: SB599.C35
 Survival of wheat pathogens in wheat and soybean residues under conservation
 tillage systems in southern and central Brazil.
 Fernandez, M.R.; Fernandes, J.M.C.
 Guelph, Ont. : Canadian Phytopathological Society; 1990 Sep.
 Canadian journal of plant pathology; Revue Canadienne de phytopathologie v. 12
 (3): p. 289-294; 1990 Sep.  Includes references.
 
 Language:  English
 
 Descriptors: Mato grosso do sul; Parana; Rio grande do sul; Triticum aestivum;
 Rotations; Glycine max; Conservation tillage; Crop residues; Plant pathogenic
 fungi; Gibberella zeae; Cochliobolus sativus; Leptosphaeria nodorum; Inoculum
 density; Incidence; Inoculum; Epidemiology; Colonizing ability; Saprophytes;
 Survival
 
 
 377                                                     NAL Call. No.: 4 AM34P
 Sustaining soil nitrogen for corn using hairy vetch cover crop.
 Utomo, M.; Frye, W.W.; Blevins, R.L.
 Madison, Wis. : American Society of Agronomy; 1990 Sep.
 Agronomy journal v. 82 (5): p. 979-983; 1990 Sep.  Includes references.
 
 Language:  English
 
 Descriptors: Kentucky; Zea mays; Winter; Cover crops; Vicia villosa; Secale
 cereale; Stubble; No-tillage; Tillage; Nitrogen fertilizers; Application rates;
 Crop yield; Grain; Nitrates (inorganic salts); Residual effects; Nitrogen
 
 Abstract:  Nitrogen fertility management is often complicated by inadequate
 supply, low efficiency, high losses, and the potential of polluting water
 resources. This study was conducted in 1984 and 1985 on a Maury soil (fine,
 mixed, mesic Typic Paleudalfs) in Kentucky to determine the role of a hairy
 vetch (Vicia villosa Roth) cover crop in sustaining soil N for corn (Zea mays
 L.) under no-tillage and conventional tillage. Winter cover treatments of hairy
 vetch, rye (Secale cereale L.), and corn residue were combined factorially with
 N rates of 0, 85, and 170 kg ha-1 the two tillage systems. Total soil C and N
 in the 0- to 7.5-cm depth, averaged across treatments and sampling dates, were
 21.8 and 2.07 g kg-1, respectively, in no-tillage and 16.6 and 1.70 g kg-1 in
 conventional tillage. Values were 19.8 and 1.99 g kg-1, respectively, with
 hairy vetch and 18.8 and 1.80 g kg-1 with rye. Conventional tillage caused
 rapid mineralization of soil N, as indicated by greater inorganic N
 approximately 6 wk after plowing. Nitrate apparently leached deeper into the
 soil under no-tillage than conventional tillage. Grain yield without N on the
 vetch treatment was essentially equal to yields with 170 kg N ha-1 on the rye
 or corn residue treatments-6.75, 6.75, and 6.65 Mg ha-1, respectively. Grain
 yield with vetch and 170 kg N ha-1 was 7.85 Mg ha-1. Although vetch provided a
 substantial amount of N, results suggested that to obtain optimum corn yields N
 fertilization should be reduced little, if any, with a vetch cover crop. Vetch
 appeared to add grain yield instead of reduce the need for N fertilizer.
 
 
 378                                                      NAL Call. No.: S1.S68
 Sweet clover fallow on solonetzes of Western Siberia.
 Yakovlev, V.Kh
 New York, N.Y. : Allerton Press; 1991.
 Soviet agricultural sciences (7): p. 26-28; 1991.  Translated from:
 Vsesoiuznaia akademiia sel'skokhoziaistvennykh nauk. Doklady, (7), p. 28-30.
 (20 AK1).  Includes references.
 
 Language:  English; Russian
 
 Descriptors: Siberia; Solonetzic soils; Fallow systems; Melilotus; Soil
 fertility; Green manures; Fodder crops; Soil physical properties; Soil biology;
 Hordeum vulgare; Crop yield; Rotations
 
 
 379                                                    NAL Call. No.: QL461.G4
 Tarnished plant bug (Hemiptera: Miridae) on selected cool-season leguminous
 cover crops.
 Bugg, R.L.; Wackers, F.L.; Brunson, K.E.; Phatak, S.C.; Dutcher, J.D.
 Tifton, Ga. : Georgia Entomological Society; 1990 Jul.
 Journal of entomological science v. 25 (3): p. 463-474; 1990 Jul.  Includes
 references.
 
 Language:  English
 
 Descriptors: Georgia; Vicia sativa; Hybrids; Trifolium incarnatum; Trifolium
 subterraneum; Trifolium yanninicum; Trifolium brachycalycinum; Cultivars; Host
 specificity; Insect pests; Lygus lineolaris; Population density; Longevity;
 Survival
 
 
 380                                                    NAL Call. No.: 56.9 SO3
 Temporal variation in aggregate stability on conventional and alternative
 farms.
 Mulla, D.J.; Huyck, L.M.; Reganold, J.P.
 Madison, Wis. : The Society; 1992 Sep.
 Soil Science Society of America journal v. 56 (5): p. 1620-1624; 1992 Sep.
 Includes references.
 
 Language:  English
 
 Descriptors: Washington; Aggregates; Stability; Seasonal variation; Alternative
 farming; Farming; Comparisons; Cropping systems; Erodibility; Slope; Landscape
 
 Abstract:  Low-input alternative farm management practices have been shown to
 decrease erosion rates and increase soil organic matter contents relative to
 conventional management practices in eastern Washington state. Little is known
 about the effect of such alternative practices on aggregate stability. Temporal
 variations in aggregate stability were measured at three slope positions on
 soils from adjacent farms managed for many years using conventional vs.
 alternative tillage and crop rotations. The conventional farm was first
 cultivated in 1908, and uses a winter wheat (Triticum aestivum L.)-spring pea
 (Pisum sativum L.) rotation with summer fallow every sixth year. The
 alternative farm was first cultivated in 1909, and uses a winter wheat-spring
 pea-Austrian winter peas [P. sativa ssp. arvense (L.) Poiret]-spring wheat-
 spring pea-summer fallow rotation with an alfalfa (Medicago sativa L.)-
 wheatgrass [Elymus trachycaulus (Link) Gould ex Shinn.] mixture every 19th and
 20th year. Surface soils (0-15 cm) were collected at foot-, back-, and topslope
 positions from both farms during October 1987, March 1988, and June 1988. The
 0.5- to 1.0-mm sieved aggregate-size fraction from each farm, landscape
 position, and sampling time was analyzed for aggregate stability using the
 high-energy moisture characteristic method. Aggregate stability on both farms
 decreased significantly from October to March in response to precipitation and
 cycles of winter freezing and thawing. Significant increases in stability
 occurred from March to June on both farms. These increases were interpreted in
 terms of recovery of cohesion by aggregates following their disruption during
 the winter. Differences in stability resulting from management practices on the
 two farms were not significant, even though organic C contents on the
 alternative farm were significantly higher than those on the conventional farm.
 
 
 381                                                 NAL Call. No.: 290.9 AM32T
 Temporal variation in runoff and soil loss from simulated rainfall on corn and
 soybeans.
 McIsaac, G.F.; Mitchell, J.K.
 St. Joseph, Mich. : American Society of Agricultural Engineers; 1992 Mar.
 Transactions of the ASAE v. 35 (2): p. 465-472; 1992 Mar.  Includes references.
 
 Language:  English
 
 Descriptors: Illinois; Zea mays; Glycine max; Erosion; Losses from soil
 systems; Runoff; Rain; Simulation; Slopes; Soil conservation
 
 Abstract:  Runoff and soil loss were measured from simulated rainfall applied
 to a Catlin silt loam soil at two crop stages during four growing seasons in a
 corn soybean rotation implemented on the contour and up-and-down slope. Runoff
 depth, runoff rate, soil loss/ha, and soil loss/ha-mm of runoff varied
 significantly by crop stage and by year. Runoff depth and runoff rate were
 correlated with variations in antecedent rainfall, soil moisture, residue, and
 canopy. Soil loss/ha from soybeans and soil loss/ha-mm of runoff from corn
 varied by as much as a factor of four from one year to another. Much of the
 variation in soil loss appeared to be related to variations in runoff, slope
 steepness, and antecedent rainfall. Soil loss/ha-mm of runoff 30 to 40 days
 after planting corn was significantly different across years for both row
 directions. In six of eight comparisons for soybeans, soil loss/ha-mm of runoff
 from simulated rainfall was not statistically different than from an eight-year
 study under natural rainfall. Nevertheless, this study indicates that results
 from one-time rainfall simulation may not represent the long term average for a
 soil.
 
 
 382                                                    NAL Call. No.: 56.9 SO3
 Thirty-year crop rotations and management practices effects on soil and amino
 nitrogen.
 Campbell, C.A.; Schnitzer, M.; Lafond, G.P.; Zentner, R.P.; Knipfel, J.E.
 Madison, Wis. : The Society; 1991 May.
 Soil Science Society of America journal v. 55 (3): p. 739-745; 1991 May.
 Includes references.
 
 Language:  English
 
 Descriptors: Saskatchewan; Triticum aestivum; Rotations; Soil fertility; Soil
 organic matter; Amino nitrogen; Fallow; Green manures; Long term experiments;
 Nitrogen
 
 Abstract:  Methods of assessing how agronomic practices influence soil
 productivity and sustainability are required. The effects of various agronomic
 practices on soil organic N and hydrolyzable amino N in a Udic Haploboroll were
 determined in a long-term (30-yr) crop rotation study at Indian Head,
 Saskatchewan. Practices assessed included fertilization, fallowing frequency,
 green manuring, and inclusion of a grass-legume forage crop in predominantly
 spring wheat (Triticum aestivum L.) systems. Fertilization, green manuring, or
 inclusion of a grass-legume hay crop significantly (P < 0.10) increased soil
 and amino N (amino acid N plus amino sugar N), particularly as fallowing
 frequency was reduced. When the relative molar distribution of the amino acids
 was used to assess changes in soil organic-N quality, significant and
 consistent increases in aspartic acid and decreases in arginine and leucine
 were observed; however, the differences were mainly associated with the 6-yr
 mixed and fertilized continuous wheat (Cont W) rotations. Comparison of our N-
 concentration results with an estimate of the initial (1958) N concentration
 suggests that all fallow-containing monoculture wheat rotations and
 unfertilized Cont W have failed to maintain soil N, the unfertilized 3-yr
 legume green manure-wheat-wheat system has maintained soil N, while the 6-yr
 fallow-cereal-hay (grass-legume) and fertilized Cont W systems have increased
 soil N. Hydrolyzable amino N was only marginally more effective than Kjeldahl N
 for describing changes in soil organic-matter quality.
 
 
 383                                                   NAL Call. No.: 56.8 J822
 Tillage and clover cover crop effects on grain sorghum yield and nitrogen
 uptake.
 Lemon, R.G.; Hons, F.M.; Saladino, V.A.
 Ankeny, Iowa : Soil and Water Conservation Society of America; 1990 Jan.
 Journal of soil and water conservation v. 45 (1): p. 125-127; 1990 Jan.
 Includes references.
 
 Language:  English
 
 Descriptors: Tillage; Clovers; Cover crops; Sorghum bicolor; Nitrogen; Uptake;
 Erosion control; No-tillage; Green manures; Crop yield
 
 
 384                                                    NAL Call. No.: 56.9 SO3
 Tillage and cover crop management effects on soil water and corn yield.
 Ewing, R.P.; Wagger, M.G.; Denton, H.P.
 Madison, Wis. : The Society; 1991 Jul.
 Soil Science Society of America journal v. 55 (4): p. 1081-1085; 1991 Jul.
 Includes references.
 
 Language:  English
 
 Descriptors: North Carolina; Zea mays; Coastal plain soils; Sandy soils; Crop
 management; Interactions; Fallow; Cover crops; Trifolium incarnatum;
 Subsoiling; Chiselling; Water availability; Soil water content; Crop yield;
 Growth; Grain; Dry matter; Dry conditions
 
 Abstract:  Subsoiling to alleviate compacted soil zones and planting cover
 crops to conserve soil water are accepted practices, but information regarding
 potential interactions between the two is limited. This study was designed to
 assess the effects of subsoiling and cover-crop management on soil water
 availability and corn (Zea mays L.) grain yield on Coastal Plain soils known to
 be responsive to in-row subsoiling. The experiment was conducted on a Norfolk
 loamy sand in 1985 and a Norfolk sand in 1986, both in the family of fine-
 loamy, siliceous, thermic Typic Kandiudults. Factors evaluated were subsoiling,
 cover crop (fallow or crimson clover [Trifolium incarnatum L.]), primary
 tillage (chisel plow or no-tillage) within fallow, and top-growth removal of
 crimson clover. Compared with fallow treatments, crimson clover depleted soil
 water in the surface 15 cm before corn planting by 28% in 1985 and 55% in 1986.
 Corn grain yield was reduced in the presence of crimson clover by 0.5 Mg ha-1
 in 1985 and 0.9 Mg ha-1 in 1986. In 1985 only, grain yield reduction in the
 presence of crimson clover was entirely overcome by subsoiling. Averaged across
 cover crop and primary tillage factors, subsoiling increased grain yields by
 25% (1.3 Mg ha-1) in 1985 and 86% (1.9 Mg ha-1) in 1986. Increased yields due
 to subsoiling were attributed to greater use of subsoil water by the corn crop.
 These results suggest that cover-crop desiccation should occur 7 to 10 d prior
 to corn planting to minimize the effects of soil water depletion under dry,
 early-spring conditions. Additionally, in-row subsoiling should be used on
 similar Coastal Plain soils responsive to deep tillage, irrespective of cover-
 crop use.
 
 
 385                                                  NAL Call. No.: SB327.A1B5
 Tillage and cover crop management for snap bean production.
 NeSmith, D.S.; Hoogenboom, G.
 Fort Collins, Colo : Howard F. Schwartz, Colorado State University; 1993.
 Annual report of the Bean Improvement Cooperative v. 36: p. 111-112; 1993.  In
 the series analytic: Annual report of the bean improvement cooperative.
 
 Language:  English
 
 Descriptors: Phaseolus vulgaris; Cover crops; Tillage; Crop yield; Soil
 management
 
 
 386                                                  NAL Call. No.: S539.5.J68
 Tillage and crop rotation affect corn, soybean, and winter wheat yields.
 Lund, M.G.; Carter, P.R.; Oplinger, E.S.
 Madison, WI : American Society of Agronomy, c1987-; 1993 Apr.
 Journal of production agriculture v. 6 (2): p. 207-213; 1993 Apr.  Includes
 references.
 
 Language:  English
 
 Descriptors: Wisconsin; Cabt; Zea mays; Glycine max; Triticum aestivum;
 Rotations; Crop yield; Plowing; Moldboards; No-tillage; Continuous cropping;
 Sequential cropping; Crop residues; Soil temperature; Plant height; Seed
 moisture; Crop density; Cultivars
 
 
 387                                                    NAL Call. No.: 56.9 SO3
 Tillage and crop rotation effect on characteristics of a sandy surface soil.
 Bruce, R.R.; Langdale, G.W.; Dillard, A.L.
 Madison, Wis. : The Society; 1990 Nov.
 Soil Science Society of America journal v. 54 (6): p. 1744-1747; 1990 Nov.
 Includes references.
 
 Language:  English
 
 Descriptors: Glycine max; Sorghum bicolor; Triticum aestivum; Rotations;
 Sequential cropping; No-tillage; Chiselling; Tillage; Sandy loam soils; Soil
 physical properties; Infiltration; Udic regimes
 
 Abstract:  In a thermic udic region, a summer crop species may be planted with
 or without tillage subsequent to a winter grain crop that was planted into a
 prepared seedbed. This study was conducted to identify the effect of tillage
 intensity associated with soybean [Glycine max (L.) Merr.] and grain sorghum
 [Sorghum bicolor (L.) Moench] crop sequences following winter wheat (Triticum
 aestivum L.), and the effect of summer crop species on selected physical
 characteristics of a Cecil sandy loam (clayey, kaolinitic, thermic Typic
 Kanhapludult). Through eight seasons, soybean and grain sorghum were grown in
 10 crop sequences that were imposed on three tillage treatments: conventional
 tillage (CT), in-row chisel (MT), and no-tillage (NT). Following summer crop
 harvest in the eighth season, aggregate stability, organic C, bulk density,
 air-filled pore space, particle-size distribution, and infiltration of water
 were measured. Aggregate stability at 0 to 10 mm was significantly higher for
 MT and NT than for CT. The CT treatment exhibited significantly lower bulk
 density and higher air-filled pore space than MT and NT. lnfiltration was
 significantly greater on the MT than the CT and NT treatments. Greater
 aggregate stability, higher air-filled pore space, and lower bulk density were
 measured after two or more years of grain sorghum than after soybean. The
 maintenance of wheat straw on the soil surface under the MT and NT treatment
 exhibited an effect to a depth of 75 mm and the in-row chisel treatment
 affected infiltration. Crop-rotational effects can be erased or modified by
 tillage and may only be observed under NT. Grain yield response of soybean and
 grain sorghum to changes in soil physical characteristics, as a consequence of
 crop sequence and tillage, may need to be interpreted in relation to crop
 species and cropping sequence.
 
 
 388                                                    NAL Call. No.: 56.9 SO3
 Tillage and crop rotation effects on fertility status of a hapludult soil.
 Edwards, J.H.; Wood, C.W.; Thurlow, D.L.; Ruf, M.E.
 Madison, Wis. : The Society; 1992 Sep.
 Soil Science Society of America journal v. 56 (5): p. 1577-1582; 1992 Sep.
 Includes references.
 
 Language:  English
 
 Descriptors: Alabama; Zea mays; Triticum aestivum; Glycine max; Hapludults; No-
 tillage; Conservation tillage; Tillage; Continuous cropping; Rotations; Cover
 crops; Soil ph; Soil organic matter; Bulk density; Nutrient availability; Soil
 fertility
 
 Abstract:  Tillage and crop rotations influence soil characteristics and may
 alter nutrient availability. A study was conducted at the Sand Mountain
 Substation, Crossville, AL, to determine the effects of 10 yr of conservation
 tillage and crop rotation on soil fertility. Tillage systems included no-till
 (NT) and conventional tillage (CT); crop rotations were continuous corn (Zea
 mays L.)--wheat (Triticum aestivum L.) cover (CW) continuous soybean [Glycine
 max (L.) Merr.]-wheat for cover (SW), and corn-wheat cover-soybean-wheat cover
 (CWSW). Soil pH, organic matter, bulk density, and Mehlich-1 (double-acid)
 extractable P, K, Ca, Mg, Mn, Zn, and Cu were determined on samples collected
 after 10 growing seasons. Tillage system did not affect soil pH; however, CW
 and CWSW crop rotations lowered soil pH due to applications of N fertilizers.
 Organic matter was increased from 10 g kg-1 in the surface 15 cm to 15.5 g kg-1
 in the surface 10 cm after 10 yr of NT. This represents an increase in organic
 matter of 56%, while organic matter was constant under CT. Organic matter was
 affected by crop rotation and decreased in order or CW > CWSW > SW. Bulk
 density decreased under NT compared with CT. Crop rotations decreased bulk
 density in the order of CWS > SW > CW. Double-acid-extractable nutrients were
 affected by tillage, crop rotation, and soil depth. Potassium availability was
 greater in the rotations CW and CWSW under CT than in the same crop sequence
 under NT. Rotations with a higher frequency of corn appeared to negatively
 affect P, Ca, and Mg availability due to lower soil pH values. Our results
 demonstrate that long-term soil management practices affect soil pH, organic
 matter, bulk density, and nutrient availability. They further show that
 different tillage and crop rotations may require distinctly different soil
 fertility management.
 
 
 389                                                NAL Call. No.: S494.5.S86S8
 Tillage and crop rotation effects on soil organic matter in a Typic Hapludult
 of northern Alabama.
 Wood, C.W.; Edwards, J.H.; Cummins, C.G.
 Binghamton, N.Y. : Food Products Press; 1991.
 Journal of sustainable agriculture v. 2 (2): p. 31-41; 1991.  Includes
 references.
 
 Language:  English
 
 Descriptors: Alabama; Glycine max; Zea mays; Triticum aestivum; Hapludults;
 Tillage; No-tillage; Rotations; Soil organic matter; Nitrogen; Carbon; Long
 term experiments
 
 
 390                                                 NAL Call. No.: 290.9 AM32P
 Tillage and fertilizer influences on corn and legume cover.
 Gilley, J.E.; Power, J.F.; Reznicek, P.J.; Finkner, S.C.
 St. Joseph, Mich. : The Society; 1990.
 Paper - American Society of Agricultural Engineers (90-2567): 23 p.; 1990.
 Paper presented at the "1990 International Winter Meeting", December 18-21,
 1990, Chicago, Illinois.  Includes references.
 
 Language:  English
 
 Descriptors: Cover crops; Tillage; Fertilizers; Erosion; Soil conservation
 
 
 391                                                NAL Call. No.: 100 SO82 (3)
 Tillage and rotation effects on mycorrhizal colonization in corn and soybeans.
 Ananth, S.; Sorensen, D.R.
 Brookings, S.D. : The Station; 1991.
 TB - Agricultural Experiment Station, South Dakota State University (97): 4 p.
 (soil PR 90-29); 1991.
 
 Language:  English
 
 Descriptors: South Dakota; Zea mays; Glycine max; Mycorrhizas; Tillage;
 Rotations
 
 
 392                                                    NAL Call. No.: 56.9 So3
 Tillage effects on legume decomposition and transformation of legume and
 fertilizer nitrogen-15.
 Varco, J.J.; Frye, W.W.; Smith, M. .- Smith, M.S.; MacKown, C.T.
 Madison, Wis. : Soil Science Society of America; 1993 May.
 Soil Science Society of America journal v. 57 (3): p. 750-756; 1993 May.
 Includes references.
 
 Language:  English
 
 Descriptors: Vicia villosa; Crop residues; Decomposition; Ammonium sulfate;
 Application rates; Nutrient sources; Tillage; No-tillage; Nitrogen;
 Transformation; Nitrogen cycle; Nitrogen content; Nutrient availability; Losses
 from soil
 
 Abstract:  The inclusion of legumes in cropping systems raises questions about
 their effectiveness as a N source. The objective of this study was to determine
 the effects of tillage on legume cover crop decomposition and transformation
 dynamics of legume and fertilizer 15N. Nitrogen-15-labeled hairy vetch (Vicia
 villosa Roth.) residue or fertilizer was added to soil cores contained in open-
 ended Plexiglas tubes placed in the field. Vetch residues were either placed on
 the soil surface for no-tillage (NT), or mixed with the soil for conventional
 tillage (CT). In 1984, 15NH4 15NO3 was applied at rates of 0 and 100 kg N ha-1
 and, in 1985, (15NH4)2SO4 was applied at rates of 0 and 150 kg N ha-1 to both
 NT and CT cores with a history of winter fallow. Fertilizer 15N was applied in
 solution to the soil surface. Within 30 d, 77% of the original vetch residue
 weight was lost with CT, compared with 45% with NT. Nitrogen lost from the
 residue by 30 d averaged 89% with CT and 60% with NT. At 15 d in 1985, soil
 inorganic 15N recovery for fertilizer was 78% with CT and 57% with NT, and for
 vetch it was 47% with CT and 12% with NT. Vetch 15N immobilization averaged 2.3
 times greater than fertilizer 15N with CT and 1.7 times greater with NT. The
 results indicate that N availability as measured by soil inorganic N is less
 from vetch residue than fertilizer due to both greater vetch N immobilization
 and the dependence of vetch N mineralization on decomposition rate.
 
 
 393                                                  NAL Call. No.: S539.5.J68
 Tillage, row spacing, and planting date effects on soybean following corn or
 wheat.
 Lueschen, W.E.; Ford, J.H.; Evans, S.D.; Kanne, B.K.; Hoverstad, T.R.; Randall,
 G.W.; Orf, J.H.; Hicks, D.R.
 Madison, Wis. : American Society of Agronomy; 1992 Apr.
 Journal of production agriculture v. 5 (2): p. 254-260; 1992 Apr.  Includes
 references.
 
 Language:  English
 
 Descriptors: Minnesota; Glycine max; Zea mays; Triticum aestivum; Crop yield;
 Tillage; Plowing; Moldboards; Chiselling; Discing; Ridging; No-tillage;
 Rotations; Row spacing; Planting date; Crop density; Crop residues
 
 
 394                                                    NAL Call. No.: 56.9 So3
 Tillage studies with a corn-soybean rotation: hydrology and sediment loss.
 Edwards, W.M.; Triplett, G.B.; Van Doren, D.M.; Owens, L.B.; Redmond, C.E.;
 Dick, W.A.
 Madison, Wis. : Soil Science Society of America; 1993 Jul.
 Soil Science Society of America journal v. 57 (4): p. 1051-1055; 1993 Jul.
 Includes references.
 
 Language:  English
 
 Descriptors: Glycine max; Zea mays; Rotations; Secale cereale; Cover crops;
 Conservation tillage; No-tillage; Tillage; Runoff; Soil; Losses from soil;
 Water erosion; Watersheds
 
 Abstract:  When soybean [Glycine max (L.) Merr.] is produced on sloping fields
 using conventional tillage and mechanical cultivation for weed control,
 potential soil losses are high, limiting production to relatively flat lands.
 With the advent of conservation tillage practices and herbicides for weed
 control, soybean production with tolerable soil losses on sloping fields has
 become technically possible. To evaluate soil loss under these new conditions,
 runoff and erosion were measured on six small watersheds that were farmed for 6
 yr in a corn (Zea mays L.)-soybean rotation with conservation tillage. Two of
 the watersheds were chiseled each year, two others paraplowed, and the other
 two received no-tillage. A rye (Secale cereale L.) cover crop was established
 each winter following soybean. With average yearly rainfall of 930 mm, yearly
 runoff was 63.5 mm and varied between 28 and 108 mm. Average yearly soil loss
 for the 6-yr period was 526 kg/ha, < 10% of the allowable soil loss. Two storms
 caused most of the erosion, with a single storm accounting for 42% of the total
 measured soil loss. Earlier, these same watersheds averaged 5750 kg/ha of
 measured soil loss during the corn years of a corn-wheat-meadow-meadow rotation
 with conventional tillage.
 
 
 395                                                    NAL Call. No.: 56.9 So3
 Tillage studies with a corn-soybean rotation: surface runoff chemistry.
 Owens, L.B.; Edwards, W.M.
 Madison, Wis. : Soil Science Society of America; 1993 Jul.
 Soil Science Society of America journal v. 57 (4): p. 1055-1060; 1993 Jul.
 Includes references.
 
 Language:  English
 
 Descriptors: Glycine max; Zea mays; Rotations; Secale cereale; Cover crops;
 Conservation tillage; No-tillage; Nutrients; Losses from soil; Runoff water;
 Surface water; Nutrient content; Watersheds 
 
 
 Abstract:  When soybean (Glycine max (L.) Merr.] is grown on sloping soils,
 there is a high potential for soil and nutrient losses. The purpose of this
 study was to compare nutrient losses in surface runoff across a range of
 watershed conditions when tillage practice was a variable. For 6 yr in east-
 central Ohio, nutrient concentrations and transport in surface runoff were
 measured from six small (< 1-ha) watersheds planted to a corn (Zea mays L.)-
 soybean rotation. Two watersheds were chisel plowed each year, two were
 paraplowed, and two received no-tillage. Rye (Secale cereale L.) provided
 winter cover following soybean harvest. Nitrate-N and K concentrations in
 surface runoff were greater during corn years than soybean years, but there was
 no significant difference among tillage treatments. There were no consistent
 differences between crops or among tillage practices for the transport of
 soluble P, soluble K, and total organic C (TOC). Most of the NO3-N loss was in
 the runoff from a small percentage of runoff events. Although NO3-N
 concentrations in surface runoff frequently exceeded 10 mg/L during the corn
 years, the actual amount of N lost was small. But because of year-to-year
 variation in runoff, which masked most of the differences resulting from
 cropping or tillage practice, there is a need for long-term research (> 6 yr)
 to assess the environmental risks associated with a particular management
 practice.
 
 
 396                                                 NAL Call. No.: 290.9 AM32T
 Tilth index: an approach to quantifying soil tilth.
 Singh, K.K.; Colvin, T.S.; Erbach, D.C.; Mughal, A.Q.
 St. Joseph, Mich. : American Society of Agricultural Engineers; 1992 Nov.
 Transactions of the ASAE v. 35 (6): p. 1777-1785; 1992 Nov.  Literature
 review.  Includes references.
 
 Language:  English
 
 Descriptors: Iowa; Minnesota; Tilth; Tillage; Zea mays; Continuous cropping;
 Glycine max; Rotations; Mathematical models; Literature reviews
 
 Abstract:  Tilth is a qualitative term that describes the physical state of
 soil. There is need for a quantitative understanding of soil tilth to help
 scientists, engineers, and farmers better understand how to manage soil. A
 "tilth index" based upon five soil physical properties was developed to
 quantify tilth. Values of bulk density, cone index, aggregate uniformity
 coefficient, organic matter content, and plasticity index were used to
 calculate an index, that ranges from zero for conditions unusable by the plant
 to one for a soil that is nonlimiting for plant growth. The tilth index was
 evaluated in field experiments near Ames, Iowa, and Waseca, Minnesota. The
 tilth index significantly changed during the cropping season. The tilth index
 was increased by tillage and planting operations and then decreased with time
 until harvest. The tilth index was positively correlated (r2 ranging from 0.15
 to 0.86, with 10 of 16 values more than 0.60) with yields of corn and soybean.
 When compared with a modified productivity index the tilth index was more
 responsive to tillage and provided better correlations with crop yield.
 
 
 397                                                     NAL Call. No.: 4 AM34P
 Timing nitrogen applications for corn in a winter legume conservation-tillage
 system.
 Reeves, D.W.; Wood, C.W.; Touchton, J.T.
 Madison, Wis. : American Society of Agronomy; 1993 Jan.
 Agronomy journal v. 85 (1): p. 98-106; 1993 Jan.  Includes references.
 
 Language:  English
 
 Descriptors: Alabama; Zea mays; Conservation tillage; Trifolium incarnatum;
 Cover crops; Coastal plain soils; Nitrogen fertilizers; Application rates;
 Fertilizer requirement determination; Application date; Timing; Nutrient
 uptake; Nitrogen; Use efficiency; Crop yield; Grain; Dry matter accumulation;
 Split dressings
 
 Abstract:  Fertilizer N efficiency of corn (Zea mays L.) in conservation-
 tillage systems with winter legumes such as crimson clover (Trifolium
 incarnatum L.) can possible be improved by better synchronization of legume-N
 release, fertilizer-N application time, and crop demand for N. The objective of
 this 3-yr (1986-1988) field experiment was to determine the effect of N
 application time on dry matter accumulation, N uptake, and grain yield of corn
 grown in a winter legume conservation-tillage system. Corn was planted with
 unit planters into crimson clover residue following in-row subsoiling. The
 clover was killed at midbloom every year. Treatments were a factorial
 arrangement of fertilizer N rates and application time. Nitrogen as NH4NO3 was
 broadcast at rates of 34, 67, and 134 kg ha(-1). Zero-N checks were also
 included in both clover and rye (Secale cereal L.) plots. Application times
 were at planting, or 3, 6, or 9 wk later. In addition, split applications (1/3
 at planting and the remainder 6 wk later) of the 67 and 134 kg N ha(-1) rates
 were included. In 2 of 3 yr, dry matter accumulation was not affected by N
 application time. In 1987, however, dry matter production was greater when N
 was applied at planting compared to split applications or applications later
 than 3 wk after planting. Application time affected N uptake patterns during
 the growing season, but generally did not affect total N uptake at the end of
 the season. With the exception of the first year, split N applications resulted
 in equivalent or reduced N uptake compared to application of all N at planting.
 Based on linear regression models, maximum yield was obtained with 134, 116,
 and 93 kg N ha(-1) in 1987, 1988, and 1989, respectively. After the first year,
 applying N later than 6 wk after planting reduced grain yield and split
 applications of N were not effective in increasing grain yield. These results
 suggest that the fertilizer N requirement of corn grown in winter legume
 conservation -tillage syste
 
 
 398                                                   NAL Call. No.: SB610.W39
 Tolerance of Chinese milkvetch (Astragalus sinicus) to herbicides.
 Cai, Z.L.; Brauen, S.E.; Gealy, D.R.; Johnston, W.J.; Lumpkin, T.A.
 Champaign, Ill. : The Society; 1992 Jan.
 Weed technology : a journal of the Weed Science Society of America v. 6 (1): p.
 104-107; 1992 Jan.  Includes references.
 
 Language:  English
 
 Descriptors: China; Astragalus sinicus; Green manures; Screening; Weed control;
 Chemical control; Herbicides; Selectivity; Crop damage; Phytotoxicity
 
 
 399                                                   NAL Call. No.: S596.7.D4
 Tolerance to acid soil conditions of the velvet beans Mucuna pruriens var.
 utilis and M. deeringiana.
 Hairiah, K.; Noordwijk, M. van; Setijono, S.
 Dordrecht : Kluwer Academic Publishers; 1991.
 Developments in plant and soil sciences v. 45: p. 227-237; 1991.  In the
 series analytic: Plant-soil interactions at low pH / edited by R.J. Wright,
 V.C. Baligar and R.P. Murrmann. Proceedings of the second international
 symposium, June 24-29, 1990, Beckley, West Virginia.  Includes references.
 
 Language:  English
 
 Descriptors: Mucuna pruriens; Mucuna deeringiana; Acid soils; Aluminum;
 Phytotoxicity; Roots
 
 Abstract:  Velvet beans, fast growing leguminous cover crops used in the humid
 tropics, are shallow rooted on acid soils. This might be due to an inherent
 branching pattern, to an intrinsic toxicity of the acid subsoil or to a
 relative preference for root development in the topsoil. Such preference could
 be based on soil chemical factors in the subsoil or on physical factors such as
 penetration resistance or aeration. In a field experiment with two species of
 velvet bean (Mucuna pruriens var. utilis and M. deeringiana) all topsoil was
 removed and plants were sown directly into the acid subsoil. Root development
 was neither affected by this treatment nor by P fertilization or liming. In the
 absence of topsoil good root development in the exposed upper layer of subsoil
 was possible, so the hypothesis of a toxicity per se of the subsoil could be
 rejected. To test whether poor root development in the subsoil in the presence
 of topsoil is due to an inherent branching pattern of the plant or to a
 relative preference for topsoil, a modified in-growth core technique was used.
 Local topsoil and subsoil and an acid soil with a higher exchangeable Al
 content were placed in mesh bags at different depths and at different bulk
 densities, with and without lime and/or P fertilizer. A comparison of root
 development in mesh bags placed in the topsoil or subsoil showed that position
 and thus inherent branching pattern is not important. Root development in the
 subsoil was poor when this soil was placed in a mesh bag in the topsoil, but in
 an acid soil of much higher exchangeable Al content and higher percentage Al
 saturation more roots developed. In a second experiment in mesh bags, bulk
 density of the repacked soil in the range 1.0-1.5 g cm-3 had no significant
 effect on root development. P fertilization and a high rate of liming of the
 soil placed in the mesh bag had a positive effect on root length density. It is
 concluded that poor root development in the acid subsoil under field conditions
 
 
 400                                                   NAL Call. No.: S631.F422
 Transfomrations of residual fertilizer P in a semi-arid tropical soil under
 eight-year peanut-wheat rotation.
 Aulakh, M.S.; Pasricha, N.S.
 Dordrecht : Kluwer Academic Publishers; 1991 Aug.
 Fertilizer research v. 29 (2): p. 145-152; 1991 Aug.  Includes references.
 
 Language:  English
 
 Descriptors: India; Cabt; Arachis hypogaea; Triticum aestivum; Rotations;
 Semiarid soils; Tropical soils; Phosphorus; Cycling; Transformation; Phosphorus
 fertilizers; Residual effects; Nutrient availability; Stability
 
 Abstract:  Long-term transformations of residual phosphorus (P) governs the
 availability of phosphorus to crops. Very limited information is available on
 the transformations of residual fertilizer P in semi-arid tropical soils under
 long-term crop rotations. Therefore, using sequential phosphorus fractionation
 procedure, we studied changes in labile and stable forms of inorganic and
 organic P in a semi-arid alluvial soil (Typic Ustisamments) after eight years
 of annual fertilizer P application either to one crop (alternate) or to both
 crops (cumulative) in a peanut (Arachis hypogaea) - wheat (Triticum aestivum)
 rotation. Total residual fertilizer P in soil (P recovered from P-fertilized
 minus control plots) ranged from 62 to 176 mg P kg(-1). In the alternate P
 treatments (P applied to peanut or wheat only), on an average of 3 rates of
 applied P (13, 26 and 39 kg P ha(-1)), in surface (0-15 cm) and subsurface (15
 to 30 cm) soil, respectively, residual fertilizer P consisted of 14.8 and 2.2%
 resin-P, 8.6 and 2.8% NaHCO3-P, 6.3 and 0% microbial-P, 31.4 and 4.2% NaOH-P,
 7.8 and 3.0% aggregate protected-P, 12.5 and 3.0% HCl-P, 3.4 and 0% H2SO4-P.
 The corresponding values for surface and subsurface soils of cumulative P
 treatments (P applied to both peanut and wheat) were: 12.8 and 1.6% resin-P,
 6.9 and 2.3% NaHCO3-P, 4.7 and 0% microbial-P, 32.5 and 4.2% NaOH-P, 5.6 and
 2.0% aggregate protected-P, 14.8 and 3.8% HCl-P, 6.7 and 2.1% H2SO4-P.
 Considerable lower values for the 15-30 cm depth indicate only a very small
 movement of residual P to the subsoil. Significantly lower amount of fertilizer
 P (28% and 44%) found in labile (resin, NaHCO3 and microbial P) and semi-labile
 (NaOH and sonicated NaOH P) fractions for the cumulative P treatment than
 alternate P treatment (35 and 46%, respectively) suggests that increased rates
 and frequency of applied P tend to enhance the conversion of residual P to
 stable forms which are less available to plants. About 12 to 19% of residual
 fertilizer P found as organic P in labile and semi-labile forms confirmed that
 organic P increased with long-term fertilizer management. In conclusion, the
 results of our study suggest that the alternate application of fertilizer P to
 a crop, as is shown for wheat, helps reduce the transformations of residual P
 to stable P forms.
 
 
 401                                                    NAL Call. No.: QH540.J6
 The transport of bioavailable phosphorus in agricultural runoff.
 Sharpley, A.N.; Smith, S.J.; Jones, O.R.; Berg, W.A.; Coleman, G.A.
 Madison, Wis. : American Society of Agronomy; 1992 Jan.
 Journal of environmental quality v. 21 (1): p. 30-35; 1992 Jan.  Includes
 references.
 
 Language:  English
 
 Descriptors: Oklahoma; Texas; Phosphorus; Runoff; Watersheds; Farmland;
 Bioavailability; Phosphorus fertilizers; Tillage; Minimum tillage; No-tillage;
 Rotations; Fallow; Stubble mulching; Triticum aestivum; Grasses; Arachis
 hypogaea; Sorghum bicolor; Losses from soil systems
 
 Abstract:  Bioavailable P (BAP) in agricultural runoff represents P potentially
 available for algal uptake and consists of soluble P (SP) and a variable
 portion of particulate P (PP). Evaluation of the impact of agricultural
 management on BAP in runoff will aid assessment of the resultant biological
 productivity of receiving water bodies. Soluble P, PP, and bioavailable PP
 (BPP) (estimated by NaOH extraction) were determined over a 5-yr period in
 runoff from 20 unfertilized and fertilized, grassed, and cropped watersheds in
 the Southern Plains. Soluble P, BPP, and BAP loss in runoff was reduced by
 practices minimizing erosion and runoff, with respective mean annual amounts
 ranging from 237 to 122, 1559 to 54, and 1796 to 176 g P ha-1 yr-1 (for peanut-
 sorghum [Arachis hypogaea L.-Sorghum bicolor (L.) Moench] and native grass
 watersheds, respectively). However, as vegetative cover improved, BAP (SP plus
 BPP) comprised a larger portion of total P (TP) loss (29% for peanut-sorghum
 and 88% for native grass). This results from an increasing contribution to BAP
 of SP (13% for peanut-sorghum and 69% for native grass watersheds) and BPP to
 PP (26% for peanut-sorghum and 69% for native grass watersheds). Clearly, P
 bioavailability is a dynamic function of physiochemical processes controlling
 erosion, particle size enrichment, P desorption-dissolution reactions, and
 plant residue breakdown, in addition to soil and fertilizer P management.
 Hence, the change in trophic state of a water body may not be adequately
 reflected by TP inputs only. To more reliably evaluate the biological response
 of a water body to agricultural P inputs, particularly from conservation
 tillage practices, it may be necessary to determine BAP in runoff.
 
 
 402                                                    NAL Call. No.: SB599.C8
 Triazine carryover in semi-arid conditions.
 Chivinge, O.A.; Mpofu, B.
 Guildford : Butterworths; 1990 Dec.
 Crop protection v. 9 (6): p. 429-432; 1990 Dec.  Includes references.
 
 Language:  English
 
 Descriptors: Zimbabwe; Zea mays; Arachis hypogaea; Rotations; Weed control;
 Chemical control; Atrazine; Prometon; Metolachlor; Terbuthylazine; Herbicide
 mixtures; Persistence; Herbicide residues; Leaching; Application rates;
 Phytotoxicity; Crop yield; Grain; Yield losses
 
 
 403                                                    NAL Call. No.: 100 AL1H
 Tropical corn offers new options for conservation-tillage.
 Kingery, R.C.; Reeves, D.W.; Mask, P.L.
 Auburn University, Ala. : The Station; 1993.
 Highlights of agricultural research - Alabama Agricultural Experiment Station
 v. 40 (1): p. 12; 1993.
 
 Language:  English
 
 Descriptors: Alabama; Zea mays; Conservation tillage; Rotations; Cultivars;
 Trifolium pratense; Nitrogen; Crop yield; Cost benefit analysis
 
 
 404                                                     NAL Call. No.: 26 T754
 Tropical lowland rice response to preceding crops, organic manures and nitrogen
 fertilizer.
 Meelu, O.P.; Morris, R.A.; Centeno, H.S.
 London : Butterworth-Heinemann; 1992 Jan.
 Tropical agriculture v. 69 (1): p. 96-100; 1992 Jan.  Includes references.
 
 Language:  English
 
 Descriptors: Philippines; Oryza sativa; Sequential cropping; Farmyard manure;
 Green manures; Sesbania; Vigna radiata; Zea mays; Crop yield; Residual effects;
 Urea fertilizers; Lowland areas
 
 
 405                                                    NAL Call. No.: S590.C63
 Twelve-year tillage and corp rotation effects on yields and soil chemical
 properties in northeast-Iowa.
 Karlen, D.L.; Berry, E.C.; Colvin, T.S.
 New York, N.Y. : Marcel Dekker; 1991.
 Communications in soil science and plant analysis v. 2 (19/20): p. 1985-2003;
 1991.  Includes references.
 
 Language:  English
 
 Descriptors: Iowa; Zea mays; Glycine max; Loam soils; Rotations; Continuous
 cropping; Plowing; Chiselling; Ridging; No-tillage; Sustainability; Crop yield;
 Grain; Soil ph; Soil organic matter; Phosphorus; Potassium; Calcium; Magnesium;
 Carbon; Nitrogen; Nitrate nitrogen; Carbon-nitrogen ratio; Nutrient
 availability; Soil depth; Use efficiency; Fertilizers; Application rates; Plant
 analysis; Nutrient content; Fertilizer requirement determination; Seasonal
 variation
 
 
 406                                                  NAL Call. No.: QH84.8.B46
 Urea hydrolysis in wetland soil amended with Sesbania aculeata green manure and
 rice straw.
 Khind, C.S.; Bajwa, M.S.
 Berlin : Springer International; 1993.
 Biology and fertility of soils v. 15 (1): p. 65-67; 1993.  Includes references.
 
 Language:  English
 
 Descriptors: Indian punjab; Green manures; Rice straw; Sesbania aculeata; Soil
 amendments; Urea; Hydrolysis; Decomposition
 
 
 407                                                 NAL Call. No.: QL391.N4J62
 Use of green manure crops in control of Hirschmanniella mucronata and H.
 oryzae in irrigated rice.
 Prot, J.C.; Soriano, I.R.S.; Matias, D.M.; Savary, S.
 Lake Alfred, Fla. : Society of Nematologists; 1992 Mar.
 Journal of nematology v. 24 (1): p. 127-132; 1992 Mar.  Includes references.
 
 Language:  English
 
 Descriptors: Oryza sativa; Hirschmanniella mucronata; Hirschmanniella oryzae;
 Sesbania; Aeschynomene; Green manures; Nematode control; Rotations
 
 Abstract:  Four field experiments were conducted to study the effect of
 Sesbania rostrata and Aeschynomene afraspera as rotational and green manure
 crops on the population dynamics of Hirschmanniella mucronata and H. oryzae,
 and subsequent rice yields. The sequential cropping of the legumes with rice
 controlled both nematode species. In two experiments, yield of rice was related
 to the nematode population densities at planting and harvesting of the second
 rice crop (R2 = 0.391, P less than 0.001, and R2 = 0.57, P less than 0.001),
 regardless of the treatments. Rice yield increases were attributed to
 nutritional effect of the green manure and the reduction of the nematode
 populations or the modification of a factor(s) linked to the nematode
 populations induced by their cropping. As the two leguminous crops do not
 generate direct return, using them to control the rice-root nematodes was not
 economical, despite the significant yield increase obtained.
 
 
 408                                         NAL Call. No.: NBULD3656 1992 H367
 The use of legume cover crops in an ecofallow rotation in the central Great
 Plains..  University of Nebraska--Lincoln thesis : Agronomy
 Hanson, Gordon E.
 1992; 1992.
 v, 105 leaves : ill. ; 28 cm.  Includes bibliographical references.
 
 Language:  English
 
 
 409                                                     NAL Call. No.: 10 EX72
 Using on-farm trials to study the benefits of feed legumes in barley-based
 rotations of north-west Syria.
 Thomson, E.F.; Jaubert, R.; Oglah, M.
 Cambridge : Cambridge University Press; 1992 Apr.
 Experimental agriculture v. 28 (2): p. 143-154; 1992 Apr.  Includes references.
 
 Language:  English
 
 Descriptors: Syria; Hordeum vulgare; Fallow; Rotations; Lathyrus sativus; Pisum
 sativum; Vicia sativa; Phosphorus fertilizers; Crop yield; Ewes; Lambs;
 Liveweight gain; Milk production
 
 
 410                                                     NAL Call. No.: 4 AM34P
 Utilizing legume cropping systems to reduce nitrogen fertilizer requirements
 for conservation-tilled corn.
 Oyer, L.J.; Touchton, J.T.
 Madison, Wis. : American Society of Agronomy; 1990 Nov.
 Agronomy journal v. 82 (6): p. 1123-1127; 1990 Nov.  Includes references.
 
 Language:  English
 
 Descriptors: Alabama; Zea mays; Glycine max; Rotations; Winter; Cover crops;
 Trifolium incarnatum; Seasonal cropping; Continuous cropping; Sequential
 cropping; Nitrogen fertilizers; Nutrient requirements; Application rates; Crop
 yield; Grain; Conservation tillage
 
 Abstract:  The need to reduce production costs has promoted a renewed interest
 in using legumes as a source of N for non-leguminous summer crops. Development
 of legume cropping systems which will permit reseeding of winter cover-crop
 legumes is a promising approach to reducing legume establishment costs. Field
 studies were conducted in Alabama for 4 yr on Wynnville sandy loam and Dothan
 fine-sandy loam soils (fine-loamy, siliceous, thermic, Glossic Fragiudults and
 Plinthic Paleudults, respectively) to determine the effects of both cash crop
 and winter cover-crop legumes in cropping systems on N fertilizer requirements
 of corn (Zea mays L.) grown in a conservation-tillage system. On the Wynnville
 soil, soybean (Glycine max L. Merr.) was more effective in providing early
 season N, and clover (Trifolium incarnatum L.) in providing late-season N. The
 system with both soybean and clover resulted in an even more effective
 contribution of N to corn grain yield, and a higher yield level than that of
 continuous corn regardless of N fertilizer rate. On the Dothan soil, the
 benefits of cropping systems were not as pronounced, and the responses were
 eliminated by N fertilization, suggesting increased yields were due to N and
 not to a rotation effect. On both soils, in years of adequate and inadequate
 rainfall, the reseeding crimson clover system, in combination with a soybean-
 corn rotation, consistently produced the highest yields of the systems studied,
 and provided a 68 to 159 kg N ha-1 fertilizer equivalent for corn.
 
 
 411                                                    NAL Call. No.: S590.C63
 Variability of several forms of soil nitrogen in two rice fields.
 Pettygrove, G.S.; Jiayou, D.; Williams, J.F.; Wick, C.; Hafez, A.A.B.; DeBoer,
 G.
 New York, N.Y. : Marcel Dekker; 1990.
 Communications in soil science and plant analysis v. 21 (13/16): p. 1843-1855;
 1990.  Paper presented at the "International Symposium on Soil Testing and
 Plant Analysis," August 14-18, 1989, Fresno, California.  Includes references.
 
 Language:  English
 
 Descriptors: Vicia benghalensis; Soil chemistry; Nitrogen; Rice soils; Green
 manures
 
 
 412                                                  NAL Call. No.: SB998.N4N4
 Velvetbean for the management of root-knot and southern blight in peanut.
 Rodriguez-Kabana, R.; Kloepper, J.W.; Robertson, D.G.; Wells, L.W.
 Auburn, Ala. : Organization of Tropical American Nematologists; 1992 Jun.
 Nematropica v. 22 (1): p. 75-80; 1992 Jun.  Includes references.
 
 Language:  English
 
 Descriptors: Alabama; Arachis hypogaea; Meloidogyne arenaria; Nematode control;
 Aldicarb; Cultural control; Rotations; Corticium rolfsii; Fungus control
 
 
 413                                                 NAL Call. No.: S592.7.A1S6
 Volatile loss of nitrogen during decomposition of legume green manure.
 Janzen, H.H.; McGinn, S.M.
 Exeter : Pergamon Press; 1991.
 Soil biology and biochemistry v. 23 (3): p. 291-297; 1991.  Includes
 references.
 
 Language:  English
 
 Descriptors: Lens culinaris; Green manures; Decomposition; Ammonia;
 Volatilization; Losses from soil systems
 
 Abstract:  Significant amounts of volatile ammonia (NH3) may be lost from
 agricultural ecosystems. While NH3 volatilization from fertilizers has been
 well-documented, corresponding losses from crop residues, particularly legume
 green manures, have not been adequately quantified. Ammonia losses from
 decomposing lentil (Lens culinaris Medik.) green manure were measured under
 controlled conditions by applying residue to soil inside sealed chambers,
 establishing air flow and periodically measuring accumulated NH3 loss using
 acid traps. Three consecutive experiments were conducted to determine the
 effect of residue placement, air flow rate and green manure composition,
 respectively. The first experiment, using a relatively slow flow rate (0.07
 chamber displacements min(-1)), demonstrated significant volatilization of NH3
 (5% of applied N after 56 days) from green manure placed on or suspended above
 the soil. Incorporating the green manure into soil almost eliminated NH3
 losses. Drying and rewetting the residues after the initial 28 days had only a
 small stimulatory effect on subsequent volatile losses. A second experiment
 indicated that maximum volatilization could be achieved at air flow rates of
 0.3 chamber displacements min(-1) or higher. A third experiment, using an
 optimum flow rate (0.5 displacements min(-1)), demonstrated significantly
 higher volatile N losses from field-grown lentil material (14% over 14 days)
 than from hydroponically cultured lentil material (8% over 14 days). This
 difference was attributed, in part, to higher soluble N concentrations in the
 former residue. Ammonia volatilization consistently demonstrated similar
 temporal patterns: a rapid initial flush, apparently from the ammonification of
 labile N, followed by an indefinite period of slow volatilization, probably
 from the mineralization of more recalcitrant N fractions. The volatile loss of
 labile N from decomposing green manure may appreciably diminish its fertility
 benefit and represent an important
 
 
 414                                                  NAL Call. No.: QD415.A1J6
 Volatile seed germination inhibitors from plant residues.
 Bradow, J.M.; Connick, W.J. Jr
 New York, N.Y. : Plenum Press; 1990 Mar.
 Journal of chemical ecology v. 16 (3): p. 645-666; 1990 Mar.  Includes
 references.
 
 Language:  English
 
 Descriptors: Allium cepa; Daucus carota; Lycopersicon esculentum; Allelopathy;
 Volatile compounds; Germination inhibitors; Cover crops
 
 Abstract:  Volatile emissions from residues of the winter cover legumes,
 Berseem clover (Trifolium alexandrinum L.). hairy vetch [Vicia hirsuta (L.)
 S.F. Gray], and crimson clover (Trifolium incarnatum L.), inhibited germination
 and seedling development of onion, carrot. and tomato. Using GC-MS, 31 C2-C10
 hydrocarbons, alcohols, aldehydes, ketones, esters, furans, and monoterpenes
 were identified in these residue emission mixtures. Mixtures of similar
 compounds were found in the volatiles released by herbicide-treated aerial and
 root residues of purple nutsedge (Cyperus rotundus L.) and the late-season
 woody stems and roots of cotton (Gossypium hirsutum L.). Vapor-phase onion,
 carrot. and tomato seed germination bioassays were used to determine the time-
 and concentration-dependent inhibition potential of 33 compounds that were
 either identified in the plant residue emissions or were structurally similar
 to identified compounds. Cumulative results of the bioassays showed that (E)-2-
 hexenal was the most inhibitory volatile tested, followed by nonanal, 3-
 methylbutanal, and ethyl 2-methylbutyrate. All the volatile mixtures examined
 contained at least one compound that greatly inhibited seed germination.
 
 
 415                                                   NAL Call. No.: 56.8 J822
 Water use evaluation of winter cover crops for no-till soybeans.
 Zhu, J.C.; Gantzer, C.J.; Anderson, S.H.; Beuselinck, P.R.; Alberts, E.E.
 Ankeny, Iowa : Soil and Water Conservation Society of America; 1991 Nov.
 Journal of soil and water conservation v. 46 (6): p. 446-449; 1991 Nov.
 Includes references.
 
 Language:  English
 
 Descriptors: Missouri; Glycine max; Poa compressa; Stellaria media; Bromus
 tectorum; Cover crops; Winter; No-tillage; Crop weed competition; Soil water
 content; Water use; Time
 
 
 416                                                   NAL Call. No.: SB610.W39
 Weed and corn (Zea mays) responses to a hairy vetch (Vicia villosa) cover crop.
 Hoffman, M.L.; Regnier, E.E.; Cardina, J.
 Champaign, Ill. : The Weed Science Society of America; 1993 Jul.
 Weed technology : a journal of the Weed Science Society of America v. 7 (3): p.
 594-599; 1993 Jul.  Includes references.
 
 Language:  English
 
 Descriptors: Ohio; Cabt; Zea mays; No-tillage; Cover crops; Vicia villosa;
 Cultural weed control; Alternative farming; Low input agriculture; Glyphosate;
 Application rates; Efficacy; Chenopodium album; Competitive ability; Crop
 yield; Yield losses; Sowing date
 
 
 417                                                   NAL Call. No.: SB610.W39
 Weed control in oat (Avena sativa)-alfalfa (Medicago sativa) and effect on next
 year corn (Zea mays) yield.
 Moomaw, R.S.
 Champaign, Ill. : The Weed Science Society of America; 1992 Oct.
 Weed technology : a journal of the Weed Science Society of America v. 6 (4): p.
 871-877; 1992 Oct.  Includes references.
 
 Language:  English
 
 Descriptors: Nebraska; Cabt; Avena sativa; Medicago sativa; Zea mays; Herbicide
 resistance; Rotations; No-tillage; Weed control; Herbicides; Crop density; Crop
 yield; Drought
 
 
 418                                                NAL Call. No.: 275.29 IO9PA
 Weed management guide for 1991.
 Hartzler, R.G.; Owen, M.D.K.
 Ames, Iowa : The Service; 1990 Dec.
 PM - Iowa State University, Cooperative Extension Service v.): 48 p.; 1990 Dec. 
 Includes references.
 
 Language:  English
 
 Descriptors: Zea mays; Glycine max; Weed control; Cultural control; Chemical
 control; Herbicides; Tillage; Rotations
 
 
 419                                                NAL Call. No.: S544.3.N6N62
 Weed management in peanuts.
 York, A.C.
 Raleigh, N.C. : The Service; 1991 Dec.
 AG - North Carolina Agricultural Extension Service, North Carolina State
 University v.): p. 43-77; 1991 Dec.  In the series analytic: 1992 Peanuts.
 
 Language:  English
 
 Descriptors: North Carolina; Arachis hypogaea; Weed control; Rotations;
 Cultivation; Herbicides; Application rates; Application date; Weeds; Hay;
 Safety
 
 
 420                                                    NAL Call. No.: 79.8 W41
 Weed seedbank response to tillage, herbicides, and crop rotation sequence.
 Ball, D.A.
 Champaign, Ill. : Weed Science Society of America; 1992.
 Weed science v. 40 (4): p. 654-659; 1992.  Paper presented at the "Symposium on
 crop/weed management and the dynamics of weed seedbanks," February 11, 1992,
 Orlando, Florida.  Includes references.
 
 Language:  English
 
 Descriptors: Zea mays; Phaseolus vulgaris; Beta vulgaris; Weed biology; Weed
 control; Chemical control; Herbicides; Seed banks; Plowing; No-tillage;
 Conservation tillage; Population dynamics; Cropping systems; Models
 
 Abstract:  Changes in the weed seedbank due to crop production practices are an
 important determinant of subsequent weed problems. Research was conducted to
 evaluate effects of primary tillage (moldboard plowing and chisel plowing),
 secondary tillage (row cultivation), and herbicides on weed species changes in
 the soil seedbank in three irrigated row crop rotational sequences over a 3-yr
 period. The cropping sequences consisted of continuous corn for 3 yr,
 continuous pinto beans for 3 yr, or sugarbeets for 2 yr followed by corn in the
 third year. Cropping sequence was the most dominant factor influencing species
 composition in the seedbank. This was partly due to herbicide use in each
 cropping sequence producing a shift in the weed seedbank in favor of species
 less susceptible to applied herbicides. A comparison between moldboard and
 chisel plowing indicated that weed seed of predominant species were more
 prevalent near the soil surface after chisel plowing. The number of predominant
 annual weed seed over the 3-yr period increased more rapidly in the seedbank
 after chisel plowing compared to moldboard plowing unless effective weed
 control could be maintained to produce a decline in seedbank number. In this
 case, seedbank decline was generally more rapid after moldboard plowing. Row
 cultivation generally reduced seedbanks of most species compared to
 uncultivated plots in the pinto bean and sugarbeet sequences. A simple model
 was developed to validate the observation that rate of change in the weed
 seedbank is influenced by type of tillage and weed control effectiveness.
 
 
 421                                            NAL Call. No.: MeUUniv. 1992 S8
 Weed suppression in no-till broccoli using crimson clover, barley and pea cover
 crops..  PLANT, SOIL AND ENVIRONMENT SCIENCE - 1992
 Sutch, Barbara Ann, Orono, Me.,; 1992.
 81 leaves : ill. ; 28 cm.  Includes vita.  Bibliography: leaves 73-80.
 
 Language:  English
 
 Descriptors: No-tillage; Weeds; Broccoli
 
 
 422                                                    NAL Call. No.: 23 AU783
 Wheat response after temperature crop legumes in south-eastern Australia.
 Evans, J.; Fettell, N.A.; Coventry, D.R.; O'Connor, G.E.; Walsgott, D.N.;
 Mahoney, J.; Armstrong, E.L.
 Melbourne : Commonwealth Scientific and Industrial Research Organization; 1991.
 Australian journal of agricultural research v. 42 (1): p. 31-43. maps; 1991.
 Includes references.
 
 Language:  English
 
 Descriptors: New South Wales; Victoria; Triticum; Legumes; Nitrogen; Nutrient
 availability; Rotations; Soil fertility; Varieties; Yield response functions
 
 
 423                                                    NAL Call. No.: 56.9 SO3
 Wheat stubble management affects growth, survival, and yield of winter grain
 legumes.
 Huggins, D.R.; Pan, W.L.
 Madison, Wis. : The Society; 1991 May.
 Soil Science Society of America journal v. 55 (3): p. 823-829; 1991 May.
 Includes references.
 
 Language:  English
 
 Descriptors: Idaho; Triticum aestivum; Pisum sativum; Lens culinaris; No-
 tillage; Phosphorus fertilizers; Potassium fertilizers; Stubble cultivation;
 Growth; Survival; Winter hardiness; Crop yield
 
 Abstract:  The adoption of no-tillage systems in the Pacific Northwest will
 benefit from the development of crop rotations that complement winter wheat
 (Triticum aestivum L.). Experiments were conducted during 1986-1987 and
 1988-1989 to determine the effects of wheat residue and fertility management on
 the growth, winter survival, and yield of 'Glacier' Austrian winter pea (Pisum
 sativum subsp. arvense L.) and winter lentil (Lens colinaris Medik.). No-
 tillage (NT) and no-tillage with reduced stubble (NT-SR) enhanced soil moisture
 conservation and increased the early growth of Austrian winter pea (AWP),
 compared with conventional tillage (CT). Decreased shoot mass of winter lentil
 (WL) in NT, and elongated stems and reduced branching of AWP and WL in NT, were
 attributed to shading by stubble that reduced photosynthetically active
 radiation and red/far-red ratios. Winter survival of AWP during 1986-1987 was
 reduced in NT (78%), compared with NT-SR (91%) and CT (96%), but no differences
 occurred in 1988-1989. Less aboveground tissue necrosis of surviving AWP
 occurred in NT than in NT-SR and CT for both years. Greater average yields in
 NT (3568 kg ha-1) and NT-SR (3530 kg ha-1) than in CT (2700 kg ha-1) were
 correlated with greater fall growth and less winter injury. Residue management
 did not influence the yield of WL. Applied P and K did not have consistent
 effects on winter survival or yield. These results indicate that winter grain
 legumes can be used to complement wheat production in the design of no-tillage
 rotations.
 
 
 424                                                NAL Call. No.: S544.3.N3C66
 When should and alfalfa field be replaced?.
 Myer, G.L.; Lewis, S.R.; Pardew, J.B.
 Reno, Nev. : The College; 1990.
 Fact sheet - College of Agriculture, University of Nevada-Reno, Nevada
 Cooperative Extension (90-07): 4 p.; 1990.
 
 Language:  English
 
 Descriptors: Nevada; Medicago sativa; Rotations
 
 
 425                                               NAL Call. No.: SB320.7.M3V43
 Winter cover crops.
 Sharp, D.
 College Park, Md. : Cooperative Extension Service; 1990.
 Vegetable views newsletter v. 1 (2): p. 7-8; 1990.
 
 Language:  English
 
 Descriptors: Maryland; Cover crops; Erosion control; Legumes; Nitrogen
 fixation; Weed control
 
 
 426                                                     NAL Call. No.: S79.E37
 Yield and nitrogen content of legume cover crops grown in Mississippi.
 Varco, J.J.; Sanford, J.O.; Hairston, J.E.
 Mississippi State, Miss. : The Station; 1991 Aug.
 Research report - Mississippi Agricultural and Forestry Experiment Station v.
 16 (10): 4 p.; 1991 Aug.  Includes references.
 
 Language:  English
 
 Descriptors: Mississippi; Cover crops; Legumes; Crop yield; Nitrogen content
 
 
 427                                                     NAL Call. No.: 450 C16
 Yield effect of pulses on subsequent cereal crops in the northern prairies.
 Wright, A.T.
 Ottawa : Agricultural Institute of Canada; 1990 Oct.
 Canadian journal of plant science; Revue canadienne de phytotechnie v. 70 (4):
 p. 1023-1032; 1990 Oct.  Includes references.
 
 Language:  English
 
 Descriptors: Saskatchewan; Triticum aestivum; Hordeum vulgare; Vicia faba; Lens
 culinaris; Pisum sativum; Rotations; Sequential cropping; Tillage; Seeds; Crop
 yield; Yield increases; Nitrogen fertilizers; Nutrient availability
 
 
 428                                                    NAL Call. No.: 23 AU783
 The yield of wheat following lupins: effects of different lupin genotypes and
 management.
 Hamblin, J.; Delane, R.; Bishop, A.; Adam, G.
 Melbourne : Commonwealth Scientific and Industrial Research Organization; 1993.
 Australian journal of agricultural research v. 44 (4): p. 645-659; 1993.
 Includes references.
 
 Language:  English
 
 Descriptors: Western australia; Lupinus albus; Lupinus angustifolius; Lupinus
 varius; Genotypes; Triticum; Crop management; Crop yield; Rotations
 
 
 429                                                    NAL Call. No.: 23 AU792
 Zinc deficiency in wheat and lupins in Western Australia is affected by the
 source of phosphate fertiliser.
 Riley, M.M.; Gartrell, J.W.; Brennan, R.F.; Hamblin, J.; Coates, P.
 East Melbourne : Commonwealth Scientific and Industrial Research Organization;
 1992.
 Australian journal of experimental agriculture v. 32 (4): p. 455-463; 1992.
 Includes references.
 
 Language:  English
 
 Descriptors: Western australia; Lupinus angustifolius; Triticum aestivum; Trace
 element deficiencies; Zinc; Zinc fertilizers; Long term experiments; Rock
 phosphate; Superphosphates; Diammonium phosphate; Rotations
 
 
 
 
 
                                   Author Index
 
 Abdul-Baki, A.A.  262
 Adam, G.  428
 Adamsen, F.J.  216
 Aflkpui, G.K.S.  118
 Aggarwal, G.C.  29
 Ahmed, S.  15
 Alberta, Alberta Agriculture  220
 Alberts, E.E.  415
 Allmaras, R.R.  50
 Ambrosious, J.E.  36
 Amir, I.  217
 An, Z.Q.  155
 An, Zhi-qiang,  175p
 Ananth, S.  391
 Andersen, R.N.  347
 Anderson, G.W.  118
 Anderson, I.C.  324
 Anderson, S.H.  154, 415
 Anderson, W.K.  199
 Andrade, F.H.  255
 Andraski, T.W.  349
 Angers, D.A.  88, 238
 Antoun, H.  172, 292, 319
 Armstrong, E.L.  422
 Arrigo, N.M.  74
 Asakawa, S.  79
 Asghar, M.  49, 110
 Atallah, T.  289
 Aulakh, M.S.  222, 225, 400
 Auld, D.L.  133
 Backman, P.A.  18
 Badaruddin, M.  180
 Baddesa, H.S.  225
 Bagayoko, M.  132
 Baglio, J.V.  260
 Bahl, G.S.  225
 Bahler, C.C.  119
 Bahr, J.R.  94
 Bailey, J.E.  273
 Bailey, K.L.  137
 Bailey, L.D.  296
 Bailie, J.E.  174, 235
 Bajwa, M.S.  406
 Baker, J.B.  213
 Balasubramanian, V.  170
 Baldridge, D.  20
 Ball, D.A.  420
 Bandele, O.A.  259
 Barber, K.L.  54
 Barker, K.R.  123, 169
 Barnes, P.L.  331
 Basson, S.  152
 Basta, N.T.  105
 Bauder, J.W.  72
 Bauer, P.J.  52
 Beaule, R.  15
 Becker, D.L.  234
 Becker, M.  181, 372
 Bell, M.J.  114
 Bender, A.  130
 Benoit, D.L.  28
 Benson, V.W.  260
 Berg, R.D.  293
 Berg, W.A.  401
 Bergen, P.  95
 Berglund, D.R.  362
 Berry, E.C.  405
 Beste, C.E.  330
 Beuselinck, P.R.  415
 Biederbeck, V.O.  38, 100, 102, 166, 296
 Bischoff, J.  130
 Bishop, A.  428
 Bissonnette, N.  238
 Black, J.R.  369
 Blackmer, A.M.  264, 354
 Blevins, R.L.  218, 377
 Blue, W.G.  295
 Bodker, L.  203
 Bole, J.B.  166
 Bolland, M. D. A.  322
 Bolland, M.D.A.  77, 323
 Bolton, F.  150
 Boparai, B.S.  107
 Boquet, D.J.  316
 Bouldin, D.R.  27
 Bourassa, J.  172, 292, 319
 Bowen, W.T.  27, 158
 Bowmer, K.H.  16
 Bowren, K.E.  101, 102
 Bradford, S.  78
 Bradow, J.M.  414
 Brauen, S.E.  398
 Bremer, A.H.  33
 Bremer, E.  274, 345
 Brennan, R.F.  429
 Broadway, R.  57, 246
 Brock, T.A.  72
 Brown, J.R.  154, 266
 Brown, P.R.  99
 Brown, R.E.  320
 Browne, J.  42
 Bruce, R.R.  73, 353, 387
 Brunson, K.E.  48, 379
 Buchanan, M.  25, 308, 344
 Buckerfield, J.C.  89
 Bugg, R.L.  48, 379
 Buhler, D.D.  211
 Bundy, L.G.  349
 Buresh, R.J.  160, 247
 Burmester, C.H.  283
 Burton, R.O. Jr  113
 Bushby, H.V.A.  114
 Byers, R.A.  119
 Cabelguenne, M.  24
 Cahn, M.D.  27
 Cai, Z.L.  398
 Campbell, C.A.  38, 100, 101, 102, 103, 382
 Canada  101
 Carden, E.L.  8, 339, 340, 356
 Cardina, J.  62, 416
 Carlson, C.  130
 Carlson, G.R.  96
 Carsky, R.J.  158
 Carter, D.L.  293
 Carter, P.R.  261, 386
 Cartwright, B.  12, 309
 Castillo, E.G.  160
 Castner, E.P.  186
 Celetti, M.J.  196, 197
 Centeno, H.S.  404
 Chalifour, F.P.  172, 292, 319
 Chalk, P.M.  30
 Chan, K.Y.  128
 Chandler, K.  28
 Chase, C.  92, 93
 Chaudhary, S.L.  325
 Cheam, A.H.  231
 Chivinge, O.A.  402
 Christenson, D.R.  171
 Christie, B.R.  39
 Christmas, E.P.  206
 Chua, T.T.  160
 Claassen, M.M.  67
 Clancy, J.A.  19
 Clapham, W.M.  129
 Clark, A.J.  298
 Clark, E.A.  39
 Clark, R.T.  69
 Clegg, M.D.  290
 Coates, P.  429
 Cohn, M.A.  213
 Coleman, G.A.  401
 Colvin, T.S.  396, 405
 Connick, W.J. Jr  414
 Conti, M.E.  74
 Cook, R.  116
 Cook, R.J.  267
 Coolman, R.M.  200
 Copeland, P.J.  50, 70, 336
 Corak, S.J.  221
 Costantini, A.O.  74
 Coventry, D.R.  6, 7, 422
 Cox, F.R.  281, 282
 Cravo, M.S.  27, 60, 258, 272
 Crews, J.R.  332
 Crookston, R.K.  50, 70, 189, 336
 Cross, R.B.  257
 Cruse, R.M.  215
 Cudnohufsky, J.  97
 Cummins, C.G.  389
 Curl, E.A.  63
 Curran, W.S.  135
 Currin, R.E. III  65
 Dabney, S.M.  291, 316
 Damicone, J.P.  80, 355
 Danso, S.K.A.  156
 Datta, S.K.De  247
 Davis, J.M.L.  342
 De Waele, D.  152
 DeBoer, G.  411
 Decker, A.M.  43, 161, 298
 Deep, I.W.  207
 DeFelice, M.S.  55, 209, 360
 DeGregorio, R.  42
 Delane, R.  428
 Denton, H.P.  61, 384
 Derksen, D.A.  28, 138, 139
 Deziel, G.  42
 Diamond, J.  333
 Dick, W.A.  44, 394
 Dickerson, O.J.  368
 Dickson, D.S.  242
 Dillard, A.L.  387
 Ditterline, R.  20
 Dizon, M.A.  178
 Dobbs, T.L.  234
 Doran, J.W.  56, 222
 Dormaar, J.F.  312
 Doster, D.H.  206
 Dowler, C.C.  185
 Downing, J.L.  15
 Drury, C.F.  81
 Drye, C.E.  368
 Duffy, M.  92, 93
 Dukpa, P.  269
 Dunand, R.T.  213
 Dunn, G.H.  226
 Dunn, R.  20
 Dunphy, E.J.  1
 Dutcher, J.D.  48, 173, 278, 305, 379
 Dyke, P.T.  24
 Eason, J.T.  334
 Easton, G.D.  286
 Echeverria, H.E.  255
 Echtenkamp, G.W.  149
 Eckert, D.J.  31
 Edwards, C.R.  357
 Edwards, D.G.  230
 Edwards, I.  163
 Edwards, J.H.  10, 334, 388, 389
 Edwards, L.M.  204
 Edwards, W.M.  44, 394, 395
 El-Hout, N.M.  264
 Elliot, P.C.  212
 Ellis, J.R.  176
 Elmore, C.D.  75, 371
 Enache, A.J.  373
 Erbach, D.C.  396
 Esau, R.  32
 Evans, D.R.  116
 Evans, J.  422
 Evans, S.D.  363, 364, 393
 Evanylo, G.K.  280
 Everson, D.O.  131
 Ewing, R.P.  384
 Exner, D.N.  215
 Ezueh, M.I.  299
 Faghihi, J.  357
 Fairey, N.A.  270
 Faris, M.A.  17
 Fawcett, R.G.  64
 Fay, P.K.  96
 Fellows, G.M.  96
 Ferguson, M.  314
 Fernandes, J.M.C.  376
 Fernandez, M.R.  376
 Ferris, H.  370
 Ferris, J.M.  357
 Fettell, N.A.  422
 Findlay, W.I.  81
 Finkner, S.C.  390
 Fisher, J.R.  86
 Fixen, P.E.  76
 Flowerday, A.D.  304
 Foltz, J.C.  165, 198
 Foord, K.E.  370
 Ford, J.H.  336, 363, 364, 393
 Fortnum, B.A.  65
 Foster, R.K.  117
 Foulke, J.  68
 Fox, J.A.  358
 Francl, L.J.  275
 Frankenberger, W.T. Jr  294
 Frans, R.E.  26, 142, 245
 Friesen, G.H.  318E
 Frye, W.W.  218, 221, 377, 392
 Fuentes, M.  183
 Fulkerson, R.S.  39
 Furoc, R.E.  178
 Gallaher, B.N.  21
 Gallaher, R.N.  232, 242, 277, 341, 352
 Gallant, C.E.  204, 333
 Gantzer, C.J.  154, 415
 Gardner, W.K.  64
 Garrity, D.P.  160
 Gartrell, J.W.  429
 Gealy, D.R.  398
 Gelderman, R.  253, 254
 Geremia, R.  139
 Gerwing, J.  253, 254
 Ghaffar, A.  315
 Giesler, G.G.  184
 Gill, D.W.  284
 Gill, G.  231
 Gilley, J.E.  390
 Gilligan, C.A.  14
 Gilmour, J.T.  239
 Gladstones, J.S.  83
 Goldern, A.M.  133
 Gordon, W.B.  63
 Gorelick, S.M.  348
 Goyal, S.  265
 Goyal, S.K.  106
 Granier, J.  217
 Grant, I.F.  193
 Gray, M.E.  159
 Greathead, A.S.  99
 Green, C.C.  52
 Greenfield, P.L.  205
 Griffin, J.L.  213, 291, 307
 Griffin, T.S.  171, 287
 Griffith, D.R.  85, 206
 Grubinger, V.P.  233
 Grundon, N.J.  230
 Guinto, D.F.  327
 Gumbs, F.A.  98
 Gunsolus, J.L.  237
 Gurung, P.R.  269
 Haahr, V.  111
 Habetz, R.J.  337
 Hafez, A.A.B.  411
 Hagendorf, B.A.  21
 Hairiah, K.  399
 Hairston, J.E.  426
 Hall, M.R.  118
 Hall, R.  121, 122
 Hamblin, J.  124, 428, 429
 Hamilton, S.D.  30
 Hammond, R.B.  201, 346
 Hanlon, E.A.  352
 Hanson, Gordon E.  408
 Hanson, J.C.  298
 Hanudin  288
 Hardin, P.D.  260
 Harger, T.J.  307
 Harper, J.K.  113
 Harper, Jayson K.  87
 Harris, G.H.  171, 303
 Hartman, G.L.  288
 Hartwig, N.L.  263
 Hartzler, R.  375
 Hartzler, R.G.  418
 Harvey, R.G.  35
 Hatzios, K.K.  37
 Havlin, J.L.  67
 Hayward, A.C.  288
 Heatherly, L.G.  75, 371
 Heenan, D.P.  128, 210
 Hegde, R.S.  11
 Helms, T.C.  362
 Helsel, Z.R.  55
 Hemamda, H.  157
 Henderson, A.B.  341
 Hendrix, J.W.  155
 Hendro, S.M.E.  276
 Henn, R.A. 275
 Hennebert, P.  194
 Henson, G.T.  155
 Herbek, J.H.  218
 Herbel, K.L.  297
 Hergert, G.W.  69
 Herridge, D.F.  252
 Herrington, B.E. Jr  367
 Hershman, D.E.  155
 Hesterman, O.B. 171, 287, 303, 351
 Hicks, D.R.  91, 363, 364, 393
 Hines, T.E.  37
 Hinman, H.  2
 Hoffman, L.D.  119
 Hoffman, M.L.  416
 Hofstetter, B.  301
 Holderbaum, J.F.  161
 Holford, I.C.R.  120
 Hong, W.F.  288
 Hons, F.M.  383
 Hooda, I.S.  265
 Hoogenboom, G.  385
 Hopmans, P.  30
 Hopper, F.L.  54
 Hornbaker, R.H.  168
 Hornby, D.  14
 Hornick, S.B.  9
 Hoverstad, T.R.  347, 363, 364, 393
 Hoyt, G.D.  200
 Huang, W.  40
 Huettel, R.N.  275
 Huggins, D.R.  423
 Hume, D.J.  365
 Hurst, H.R.  53, 126
 Hussain, A.  315
 Huyck, L.M.  380
 Ibeabuci, I.O.  5
 Ikombo, B.M.  127
 Ilnicki, R.D.  373
 Imbriani, J.L.  236
 Imholte, A.A.  261
 Ingram, D.M.  267
 Insam, H.  312
 Jacobi, J.C.  18
 Jans, Desiree  220
 Janzen, H.H.  102, 103, 166, 413
 Jaubert, R.  409
 Jensen, E.S.  111
 Jensen, Tom  220
 Jiayou, D.  411
 Johanson, J.B.  294
 Johnson, A.W.  133
 Johnson, D.H.  26, 191, 245
 Johnson, G.A.  55
 Johnson, K.D.  329
 Johnson, W.C. III  62
 Johnson, W.G.  26, 245
 Johnston, H.W.  196, 197, 204
 Johnston, W.J.  398
 Jones, C.A.  24
 Jones, J.W.  158
 Jones, O.R.  401
 Jordan, D.L.  26, 245
 Kaaheh, W.  278
 Kaakeh, W.  173, 305
 Kahn, B.A.  343
 Kamprath, E.J.  284
 Kanne, B.K.  347, 363, 364, 393
 Kapusta, G.  359
 Karanja, D.R.  127
 Karlen, D.L.  56, 405
 Kaufusi, P.  110
 Keating, B.A.  127
 Keisling, T.C.  142
 Kelley, K.W.  113
 Kells, J.J.  97
 Kendig, J.A.  26
 Kendig, S.M.  310
 Kharel, D.R.  269
 Khind, C.S.  143, 406
 Kimpinski, J.  196, 197, 204, 333
 King, L.D.  25, 308, 344
 King, P.S.  13, 51, 187, 356, 366
 Kingery, R.C.  403
 Kirkpatrick, T.L.  192
 Kissel, D.E.  67
 Klemme, R.M.  36
 Klocke, N.L.  69
 Kloepper, J.W.  412
 Knake, E.L.  359
 Knipfel, J.E.  382
 Knox, M.L.  108
 Koenigstein, K.W.  168
 Koenning, S.R.  123
 Kozub, G.C.  32
 Krausz, R.F.  359
 Kuhlman, D.E.  159
 Kulasooriya, S.A.  241
 Kurle, J.E.  336
 Ladha, J.K  181
 Ladha, J.K.  22, 147, 372
 Lafond, G.P.  100
 LaFond, G.P.  103
 Lafond, G.P.  137, 138, 139, 382
 Lal, R.  44
 Lamont, W.J. Jr  223
 Langdale, G.W.  73, 353, 387
 Lantin, R.M.  40
 Lathwell, D. J.  219
 Latiff, A.  300
 Latta, R.A.  41
 Leach, S.S.  129
 Leavitt, R.A.  97
 Lee, J.G.  165
 Leep, R.H.  97
 Lefkoff, L.J.  348
 Lefkovitch, L.P.  270
 Legere, A.  88, 238
 Lemon, R.G.  383
 Leroul, N.  203
 Letey, J.  78
 Levine, E.  86
 Lewis, S.A.  368
 Lewis, S.R.  424
 Leys, A.R.  210
 Leyshon, A.J.  38, 103
 Li, G.C.  131
 Liboon, S.P.  160
 Lichtenberg, E.  298
 Liebl, R.  115
 Liebl, R.A.  135
 Lipps, P.E.  207
 Liu, C.C.  195
 Loeppky, H.  138
 Long, J.H.  67
 Lopez-Bellido, L.  183
 Lopez-Real, J.M.  289
 Lowell, K.A.  125
 Lowenberg-DeBoer, J.  198
 Lueschen, W.E.  336, 347, 363, 364, 393
 Lumpkin, T.A.  398
 Lund, M.G.  386
 MacGuidwin, A.E.  374
 Machmud, M.  46
 MacKown, C.T.  392
 MacLeod, J.A.  204
 Madamba, C.P.  276
 Maddux, L.D.  67, 331
 Mahler, R.L.  131, 157
 Mahoney, J.  422
 Mallarino, A.P.  354
 Manguiat, I.J.  327
 Mannering, J.V.  85
 Marr, C.W.  223
 Martens, D.A.  294
 Martin, D.L.  69
 Martin, F.G.  295
 Martin, M.A.  94, 165, 198
 Martin, N.P.  91
 Martin, R.A.  197
 Marty, J.R.  24
 Mask, P.L.  403
 Mason, M.G.  248
 Mason, S.C.  132, 176
 Matias, D.M.  407
 Matocha, J.E.  54
 McComb, S.J.  36
 McCoy, E.L.  44
 McDonald, D.  228
 McGawley, E.C.  361
 McGill, W.B.  350
 McGinn, S.M.  413
 McIsaac, G.F.  381
 McKenney, D.J.  81
 McNevin, G.R.  35
 McSorley, R.  232, 242, 277
 Meelu, O.P.  178, 404
 Mehan, V.K.  228
 Meisinger, J.J.  43, 161
 Melgar, R.J.  258
 Melouk, H.A.  355
 Melton, T.A.  140
 Mendosa, T.C.  84
 Mengel, D.B.  206
 Messersmith, C.G.  34
 Meyer, A.J.  152
 Meyer, C.R.  85
 Meyer, D.W.  180
 Meyer, S.L.F.  275
 Miller, C.H.  259
 Miller, D.A.  11
 Miller, W.P.  353
 Millhollon, E.P.  184
 Minotti, P.L.  233
 Minton, N.A.  243
 Mishra, M.M.  265
 Mislevy, P.  295
 Mitchell, C.C.  266, 312
 Mitchell, C.C. Jr  332
 Mitchell, J.K.  381
 Mizen, K.A.  116
 Mohler, C.L.  224
 Moody, K.  212
 Moomaw, R.S.  149, 417
 Moore, W.F.  80, 358
 Moorman, T.B.  185
 Morrall, R.A.A.  15
 Morris, R.A.  178, 404
 Morris, T.F.  264
 Mortensen, K.  137
 Mosier, A.R.  4
 Moulin, A.P.  102
 Moyer, J.R.  32, 95
 Mpofu, B.  402
 Muehlchen, A.M.  153
 Mueller, J.D.  368
 Mughal, A.Q.  396
 Mulford, F.R.  161
 Mulla, D.J.  380
 Mullens, T.A.  370
 Mullinix, B.G. Jr  62
 Mullins, G.L.  283
 Murray, D.S.  186
 Myer, G.L.  424
 Myers, J.L.  317
 Myhre, D.L.  352
 Nagle, M.E.  286
 Nash, A.  259
 Navarro, C.A.  255
 Nedel, J.L.  19
 Nelson, W.A.  343
 Nelson, W.W.  50
 Nene, Y.L.  202
 NeSmith, D.S.  385
 Nielsen, R.L.  206
 Nigam, S.N.  228
 Noe, J.P.  236
 Noordwijk, M. van  399
 Norhayati, M.  230
 Norman, R.J.  239
 Novak, J.L.  332
 O'Bannon, J.H.  244
 O'Connor, G.E.  422
 Oficial, R.  193
 Oglah, M.  409
 Oloumi-Sadeghi, H.  86
 Olson, K.D.  91
 Onyango, Ruth M. Adhiambo  227
 Oplinger, E.S.  211, 386
 Orf, J.H.  363, 364, 393
 Ottow, J.C.G.  181
 Overstreet, C.  361
 Owen, M.D.K.  418
 Owens, L.B.  394, 395
 Oyer, L.J.  410
 Painter, K.M.  162
 Palm, C.A.  256
 Palma, R.M.  74
 Pan, W.L.  19, 423
 Papastylianou, I.  148, 156
 Pardew, J.B.  424
 Pare, T.  172, 292, 319
 Pareek, R.P.  147, 372
 Parke, J.L.  153
 Parr, J.F.  9
 Parsons, S.D.  85, 206
 Pasricha, N.S.  225, 400
 Patel, M.V.  80, 358
 Paxton, K.W.  184
 Peaden, R.  244
 Pearse, P.G.  15
 Peck, T.R.  266
 Pegues, M.L.  8
 Peoples, M.B.  114, 252
 Perez, A.S.  327
 Peterson, T.A.  249, 250, 251, 304, 321
 Pettygrove, G.S.  411
 Phatak, S.C.  48, 379
 Phillips, D.L.  260
 Phillips, L.G.  121
 Phillips, R.E.  226
 Pinochet, J.  187
 Pintor, R.M.  327
 Plant, H.W.  197
 Poe, G.L.  36
 Porter, G.A.  129, 271, 328
 Potts, W.E.  330
 Powell, G.E.  326
 Powell, N.T.  140
 Power, J.F.  182, 222, 313, 390
 Prasad, M.N.V.  23
 Prasad, R.  106
 Pratley, J.E.  64
 Prestbye, L.S.  108
 Prot, J.C.  276, 407
 Puech, J.  217
 Quigley, P.E.  41
 Quintana, J.O.  158
 Raimbault, B.A.  66
 Rand, R.E.  153
 Randall, G.W.  393
 Ranells, N.N.  58, 59
 Ranjha, A.M.  315
 Rath, M.D.  235
 Ravuri, V.  365
 Reddy, M.V.  202
 Redmond, C.E.  394
 Rees, R.M.  314
 Reeves, D.W.  397, 403
 Regan, R.P.  213
 Reganold, J.P.  380
 Regnier, E.E.  416
 Reise, R.W.  275
 Renner, K.A.  326, 369
 Reznicek, P.J.  390
 Rice, W.A.  296
 Rickerl, D.H.  63, 164, 335
 Riepe, J.R.  94
 Riley, M.M.  429
 Ritzi, R.W. Jr  82
 Roach, S.H.  52
 Roberts, B.W.  12, 309, 343
 Robertson, D.G.  8, 13, 18, 51, 187, 339, 340, 356, 366, 412
 Robertson, D.R.  338
 Robertson, J.A.  350
 Roder, W.  176, 269
 Rodriguez-Kabana, R.  8, 13, 18, 51, 187, 338, 339, 340, 356, 366, 412
 Roessler, C.E.  295
 Roeth, F.W.  136
 Roger, P.A.  193
 Rogers, P.A.  22
 Roget, D.K.  311
 Rosswall, T.  241
 Rothrock, C.S.  192, 310
 Rourke, R.V.  129
 Rovira, A.D.  311
 Rowell, C.P.  331
 Rowland, I.C.  248
 Roy, R.C.  90
 Ruf, M.E.  388
 Russelle, M.P.  351
 Sabata, R.J.  132
 Sahid, I.B.  300
 Saladino, V.A.  383
 Samaranayake, A.  141
 Samson, N.  88, 238
 Sanchez, P.A.  256
 Sanders, B.J.  293
 Sanders, D.C.  259
 Sanderson, J.B.  204
 Sanford, J.O.  426
 Sarrantonio, M.  190
 Sasser, J.N.  47, 236
 Sastroutomo, S.S.  300
 Saunders, L.  240
 Savary, S.  407
 Saxton, K.  150
 Schaalje, G.B.  95
 Schepers, J.S.  4
 Schirman, R.  2
 Schmidt, M.A.  91
 Schmitt, D.P.  123, 169, 229
 Schneekloth, J.P.  69
 Schneekloth, Joel Philip  151
 Schnitzer, M.  101, 382
 Schonbeck, M.  42
 Schreiber, M.M.  94, 208
 Scott, H.D.  142
 Sekayange, L.  170
 Sekhon, N.K.  29
 Selles, F.  38
 Seneviratne, G.  241
 Setijono, S.  399
 Seymour, M.D.  286
 Shade, H.M.  125
 Shamshuddin, J.  230
 Shapiro, C.A.  304, 320
 Sharar, M.S.  315
 Sharifuddin, H.A.H.  230
 Sharma, B.D.  107
 Sharma, H.C.  167
 Sharma, R.C.  167
 Sharma, S.N.  106
 Sharp, D.  425
 Sharpley, A.N.  401
 Shaw, D.R.  134
 Shea, P.J.  136
 Sheaffer, C.C.  351
 Sheldon, R.J.  329
 Shennan, C.  99
 Shipley, P.R.  43
 Shock, C.  240
 Shuford, J.W.  5
 Silsbury, J.H.  177
 Simmons, F.W.  115, 135
 Simpson, I.C.  193
 Simpson, J.R.  127
 Simpson, L.A.  98
 Sims, B.D.  209, 360
 Sims, J.  20
 Singh, B.  143
 Singh, B.V.  106
 Singh, K.K.  396
 Singh, R.  265
 Singh, S.  106
 Singh, S.K.  202
 Singh, Y.  143
 Singogo, W.  223
 Sipes, B.S.  169
 Sisson, J.A.  271, 328
 Sistani, K.R.  5
 Slack, S.A.  374
 Slattery, W.J.  6, 7
 Slinkard, A.E.  166, 296
 Smedegaard-Petersen, V.  203
 Smith, C.J.  30
 Smith, J.A.  174, 235
 Smith, M. .- Smith, M.S.  392
 Smith, M.A.  261
 Smith, M.S.  221
 Smith, R.T.  82
 Smith, S.J.  401
 Smolik, J.D.  164
 Smyth, T.J.  60, 258, 272
 Soil Management Collaborative Research Support Program  219
 Sorensen, D.  253, 335
 Sorensen, D.R.  391
 Sorenson, B.A.  136
 Sorenson, D.  254
 Soriano, I.R.S.  407
 Stalknecht, G.  20
 Staricka, J.A.  363, 364
 Steed, G.R.  64
 Steffey, K.L.  159
 Steinhardt, G.C.  85, 206
 Steinstra, W.C.  364
 Stewart, V.R.  96
 Stieber, T.  240
 Stienstra, W.C. d363
 Stoller, E.W.  115
 Stout, W.L.  119
 Stuart, C.A.  144, 145, 146, 367
 Sullivan, G.A.  268
 Sumner, D.R.  133
 Sutch, Barbara Ann,  421
 Sutton, J.C.  71
 Swanton, C.J.  28, 90, 118
 Sylvester-Bradley, R.  257
 Ta, T.C.  17
 Tabatabai, M.A.  105
 Talbert, R.E.  26, 191, 245
 Tasrif, A.  300
 Taylor, A.C.  210
 Taylor, R.W.  5
 Teasdale, J.R.  214, 224, 262, 330
 Tesar, M.B.  97
 Thicke, F.E.  351
 Thimmegowda, S.  112
 Thompson, A.L.  154
 Thomson, E.F.  409
 Thorsness, K.B.  34
 Thurlow, D.L.  334, 388
 Tindall, Timothy Todd,  285
 Tiraa, A.N.  49
 Todd, T.C.  104
 Touchton, J.T.  63, 397, 410
 Townley-Smith, L.  101, 102, 296
 Triplett, G.B.  394
 Turco, R.F.  329
 Ullrich, S.E.  19
 Uribe, E.  281, 282
 Utomo, M.  377
 Uzzell, G. Jr  47
 Van Bruggen, A.H.C.  99
 Van Doren, D.M.  394
 Van Kessel, C.  274, 345
 Van Rees, H.  64
 Varco, J.J.  392, 426
 Varvel, G.E.  249, 250, 251, 320, 321
 Vazquez, L.  352
 Vencill, W.K.  37
 Ventura, W.  179
 Vivekanandan, M.  76
 Volenec, J.J.  329
 Voss, R.  92
 Vough, L.R.  161
 Vyn, T.J.  66, 71, 118
 Wackers, F.L.  48, 379
 Waddle, B.A.  142
 Wagger, M.G.  58, 59, 61, 317, 384
 Wall, D.A.  318
 Walsgott, D.N.  422
 Walsh, J.D.  209, 360
 Walters, D.T.  222
 Wang, S.W.  81
 Wani, S.P.  350
 Warman, P.R.  109
 Warnes, D.D.  363, 364
 Watanabe, I.  179, 195
 Watanbe, I.  147
 Wax, L.M.  115
 Weaver, C.F.  51, 187, 338, 339
 Weaver, D.B.  8, 334, 339, 340, 356
 Webb, J.  92
 Webb, J.R.  354
 Weerakoon, W.L.  241
 Weersink, A.  90
 Weil, R.R.  125, 141
 Wells, B.R.  239
 Wells, L.  13, 51, 338, 366
 Wells, L.W.  412
 Welty, L.  20
 Welty, L.E.  108
 Werker, A.R.  14
 Wesley, R.A.  75, 371
 West, L.T.  353
 Westcott, M.  20
 Westcott, M.P.  108
 Westerman, R.B.  186
 Westerman, R.L.  266
 Whitam, K.  361
 White, R.H.  45
 Whitfield, D.M.  64
 Whiting, K.R.  189
 Whiting, Kelly Reid  188
 Wichman, D.  20
 Wick, C.  411
 Wilkins, D.E.  150
 Williams, J.F.  411
 Williams, J.R.  24, 113, 297, 331
 Williams, P.T.  171
 Williams, T.A.  116
 Williams, W.  142
 Wilson, H.P.  37
 Wilson, J.M.  124
 Wilson, R.L. Jr  73
 Windham, T.E.  144, 145, 146, 367
 Wixson, M.B.  134
 Wood, C.W.  10, 388, 389, 397
 Worsham, A.D.  45
 Wright, A.T.  302, 427
 Yadvinder-Singh  107
 Yakovlev, V.Kh  378
 Yan, L.  314
 Yiridoe, E.K.  90
 Yonts, C.D.  174, 235
 York, A.C.  419
 Young, D.L.  162
 Young, R.W.  340
 Yusoff, M.N.M.  230
 Zachariassen, J.A.  313
 Zaicou, C.  231
 Zavalin, A.A.  279
 Zentner, R.P.  38, 100, 101, 103, 139, 382
 Zhu, J.C.  415
 Zourarakis, Demetrio Periferachis,  306
 
 
 
 
                                   Subject Index
 
 1,3-dichloropropene  47, 65
 2,4-d  45, 95, 186
 Abiotic injuries  26, 97, 186, 191, 245, 360
 Abutilon theophrasti  115, 211, 214, 347
 Acid soils  109, 183, 230, 256, 284, 399
 Acidification  6, 27
 Acifluorfen  326
 Acyrthosiphon pisum  305
 Adaptation  183
 Adsorption  105
 Adverse effects  126
 Aeschynomene  179, 181, 276, 407
 Aeschynomene Americana  13, 340
 Age structure  89
 Aggregates  66, 74, 88, 107, 353, 380
 Agricultural chemicals  93, 308
 Agricultural policy  162, 234, 297
 Agricultural prices  91
 Agricultural regions  308
 Agricultural research  247, 332
 Agricultural soils  103, 121
 Agriculture  164
 Agronomy  266
 Air temperature  56, 349
 Alabama  3, 5, 10, 13, 18, 51, 63, 187, 266, 312, 332, 334, 338, 339, 340, 356,
 366, 388, 389, 397, 403, 410, 412
 Alachlor  35, 185, 211, 307
 Alberta  32, 270, 350
 Alcaligenes  79
 Aldicarb  8, 13, 51, 116, 204, 338, 339, 366, 412
 Alfalfa  36
 Alfalfa hay  93
 Alkaline phosphatase  238
 Alkaline soils  32
 Alkalinity  6
 Allelopathins  11
 Allelopathy  11, 208, 214, 414
 Allium cepa  414
 Alluvial soils3 167
 Alternative farming  93, 94, 162, 165, 234, 260, 373, 380, 416
 Aluminum  230, 399
 Amaranthus hybridus  115
 Amaranthus retroflexus  211
 Amino acids  101
 Amino nitrogen  382
 Amino sugars  101
 Ammonia  413
 Ammonium  81, 105
 Ammonium fertilizers  105, 166
 Ammonium nitrate  38, 56, 67, 99, 172, 176, 270, 319, 320, 351
 Ammonium nitrogen  160, 321
 Ammonium sulfate  267, 274, 392
 Anaerobic conditions  81
 Analytical methods  22, 249
 Animal manures  4, 314
 Animal production  252
 Annual field crops  73, 120
 Annuals  166
 Antagonists  13
 Aphanomyces  153
 Aphis craccivora 278
 Aporrectodea caliginosa  89
 Application date  59, 95, 115, 136, 237, 273, 280, 291, 326, 397, 419
 Application methods  53, 135, 136, 369
 Application rates  19, 26, 29, 32, 54, 92, 136, 149, 157, 160, 172, 209, 211,
 225, 250, 251, 253, 264, 265, 268, 271, 273, 279, 280, 281, 282, 287, 291, 292,
 317, 319, 320, 321, 326, 328, 331, 349, 351, 354, 377, 392, 397, 402, 405, 410,
 416, 419
 Aquifers  82, 348
 Arachis hypogaea  3, 13, 18, 46, 51, 62, 112, 114, 152, 225, 228, 230, 268,
 273, 338, 355, 366, 400, 401, 402, 412, 419
 Argentina  255
 Argillic horizons  280
 Arkansas  26, 144, 145, 146, 191, 245, 310, 367
 Ascochyta fabae  15
 Asia  247
 Assimilation  160, 345
 Astragalus sinicus  398
 Atrazine  16, 35, 55, 59, 97, 347, 402
 Australia  83
 Autumn  161, 207, 360, 363
 Availability  17
 Available water  171
 Avena fatua  96
 Avena sativa  16, 42, 56, 77, 93, 105, 108, 111, 129, 130, 154, 156, 171, 249,
 250, 251, 263, 271, 275, 321, 328, 333, 347, 350, 352, 374, 417
 Azolla  179, 193
 Bacteria  185
 Bacterial diseases  99, 140
 Bactericides  288
 Band placement  272
 Barley straw  294
 Base saturation  105
 Belonolaimus  104
 Beneficial insects  48
 Bentazon  307
 Bentazone  326
 Beta vulgaris  32, 96, 174, 235, 420
 Bhutan  269
 Bioassays  11, 16, 186
 Bioavailability  401
 Biodegradation  84
 Biological activity in soil  10, 74, 101, 102, 222, 238, 265, 345
 Biological competition  288
 Biological control  299
 Biological production  195
 Biomass  24, 42, 89, 100, 102, 143, 224, 238, 265, 269, 312, 316, 344, 345, 353
 Biomass production  52, 178, 209, 235, 258, 289, 373
 Biotypes  307
 Black earths  120
 Blending  78
 Blight  15, 80
 Bloat  20
 Boron  268
 Botanical composition  42
 Bradyrhizobium  114
 Bradyrhizobium japonicum  79, 365
 Brassica campestris var. rapa  16
 Brassica napus  32, 95, 96, 133, 318
 Brassica napus var. napobrassica  333
 Brassica oleracea  12, 129, 259, 373
 Brassica oleracea var. capitata  309
 Brassica oleracea var. italica  259
 Brazil  27, 60, 258, 272
 Broadcasting  272
 Broccoli  421
 Bromus diandrus  210, 231
 Bromus inermis  100, 101, 103
 Bromus rigidus  231
 Bromus tectorum  415
 Bulk density  72, 74, 107, 120, 222, 352, 388
 Burundi  194
 Butachlor  193
 Cabt  19, 25, 26, 27, 40, 41, 50, 55, 102, 115, 128, 148, 157, 160, 165, 186,
 189, 191, 194, 209, 224, 224, 228, 228, 232, 238, 245, 260, 262, 264, 277, 298,
 308, 320, 334, 349, 351, 360, 365, 386, 400, 416, 417
 Cadmium  105
 Calcareous soils  311
 Calcium  27, 31, 216, 230, 268, 405
 Calibration  24
 California  99, 370
 Calopogonium caeruleum  300
 Calopogonium mucunoides  300
 Canavalia ensiformis  27, 187
 Canopy  149
 Captan  364
 Carbofuran  193
 Carbohydrates  238
 Carbon  10, 25, 31, 67, 74, 100, 101, 105, 107, 120, 222, 238, 260, 265, 289,
 344, 345, 389, 405
 Carbon cycle  294, 312
 Carbon dioxide  100
 Carbon-nitrogen ratio  100, 101, 289, 405
 Carbonates  82
 Carthamus tinctorius  34, 202
 Case studies  40, 91, 168
 Cassia  13
 Cation exchange capacity  105
 Cations  27
 Cattle manure  176, 223
 Centrosema pubescens  300
 Cereals  64, 127, 257
 Chaff  267
 Characterization  313
 Chemical composition  88, 302
 Chemical control  8, 26, 32, 35, 55, 95, 134, 135, 186, 191, 208, 211, 212,
 245, 291, 307, 326, 360, 361, 366, 398, 402, 418, 420
 Chemical properties  138
 Chemical vs. cultural weed control  35
 Chenopodium album  37, 115, 211, 214, 330, 416
 Chernozemic soils  102
 Chernozems  100, 101, 103
 China  228, 398
 Chiselling  88, 94, 129, 211, 238, 363, 364, 384, 387, 393, 405
 Chloramben  211, 326
 Chlorimuron  191, 359, 360
 Chlorsulfuron  32, 318
 Cicer arietinum  202
 Citrullus lanatus  191
 Clay loam soils  81, 105, 207, 318
 Clay soils  16, 26, 75, 98, 222, 371
 Climatic factors  42, 122, 182, 363
 Clomazone  135, 211, 326, 359, 360
 Clopyralid  34
 Clover hay  240
 Clovers  383
 Coal mine spoil  5
 Coarse textured soils  280, 294p
 Coastal plain soils  61, 63, 280, 384, 397
 Coastal plains  216
 Cochliobolus sativus  124, 197, 376
 Colletotrichum truncatum  15
 Colonization  176
 Colonizing ability  376
 Colorado  348
 Commodities  36
 Companion crops  108
 Companion planting  285
 Comparisons  61, 93, 150, 217, 238, 274, 298, 380
 Competitive ability  416
 Composting  9
 Computer simulation  165
 Computer software 24, 85, 369
 Conservation  43
 Conservation tillage  10, 56, 63, 88, 89, 94, 95, 115, 150, 164, 238, 343, 363,
 376, 388, 394, 395, 397, 403, 410, 420
 Continuous cropping  6, 10, 14, 50, 61, 66, 67, 71, 73, 75, 76, 78, 94, 100,
 101, 103, 105, 120, 140, 154, 165, 176, 198, 207, 249, 290, 321, 331, 336, 347,
 350, 386, 388, 396, 405, 410
 Copper  105
 Corking  99
 Corn belt states of U.S.A.  165, 198
 Coronilla varia  263
 Correlated responses  19
 Correlation  80, 312, 352
 Corticium rolfsii  51, 338, 355, 366, 412
 Cost analysis  2, 367
 Cost benefit analysis  94, 139, 212, 234, 403
 Cost effectiveness analysis  354
 Costs  162, 261, 348
 Cotton  68
 Cover crops  12, 21, 25, 33, 42, 43, 48, 52, 53, 55, 56, 57, 58, 59, 90, 99,
 115, 119, 126, 142, 149, 161, 171, 182, 184, 190, 192, 200, 201, 214, 218, 221,
 222, 224, 226, 233, 235, 246, 252, 256, 261, 262, 263, 289, 291, 298, 300, 301,
 305, 309, 310, 313, 316, 317, 320, 330, 341, 343, 346, 373, 377, 383, 384, 385,
 388, 390, 394, 395, 397, 410, 414, 415, 416, 425, 426
 Coverage  42, 61
 CRiconemella  242, 275, 277
 Crop damage  26, 63, 95, 134, 135, 159, 186, 191, 245, 309, 326, 346, 359, 360,
 398
 Crop density  52, 215, 363, 364, 386, 393, 417
 Crop establishment  45, 97, 116, 149, 215, 317
 Crop growth stage  59, 76, 149, 221, 271, 280, 336
 Crop losses  237
 Crop management  4, 24, 56, 62, 100, 101, 105, 154, 163, 252, 270, 308, 384,
 428
 Crop mixtures  33, 161, 348
 Crop production  39, 41, 64, 65, 128, 138, 184, 185, 200, 221, 252, 268, 269,
 290, 296, 323, 363, 364, 367, 375
 Crop quality  19, 91, 140, 183, 270, 286, 328
 Crop residues  10, 11, 17, 25, 42, 49, 56, 61, 63, 67, 71, 81, 84, 100, 101,
 115, 164, 221, 222, 224, 235, 239, 252, 258, 345, 351, 353, 363, 376, 386, 392,
 393
 Crop rotation  175, 285
 Crop weed competition  42, 215, 237, 415
 Crop yield  1, 6, 13, 18, 19, 20, 24, 26, 27, 29, 34, 35, 37, 39, 40, 42, 44,
 45, 49, 50, 52, 55, 58, 61, 62, 65, 66, 70, 71, 73, 75, 84, 90, 91, 92, 94, 95,
 98, 99, 100, 107, 109, 111, 112, 113, 114, 115, 116, 117, 118, 119, 120, 123,
 128, 132, 136, 138, 140, 141, 142, 143, 149, 156, 157, 161, 163, 164, 167, 171,
 172, 177, 178, 179, 180, 183, 184, 189, 199, 203, 204, 205, 207, 208, 211, 212,
 215, 216, 218, 221, 223, 234, 241, 246, 250, 253, 255, 257, 258, 260, 261, 262,
 263, 265, 268, 270, 271, 272, 279, 280, 281, 283, 286, 287, 290, 291, 293, 295,
 298, 304, 307, 308, 312, 315, 317, 319, 321, 324, 325, 326, 328, 329, 331, 334,
 336, 339, 340, 342, 348, 349, 351, 354, 355, 356, 359, 362, 363, 364, 373, 375,
 377, 378, 383, 384, 385, 386, 393, 397, 402, 403, 404, 405, 409, 410, 416, 417,
 423, 426, 427, 428
 Cropping systems  17, 93, 125, 127, 133, 166, 202, 208, 229, 230, 236, 242,
 247, 281, 282, 293, 308, 356, 372, 380, 420
 Crops  72
 Crotalaria  288
 Crotalaria juncea  167, 178
 Crotalaria spectabilis  187
 Crown  197, 207
 Cucumis melo  48, 223
 Cucumis sativus  37, 191
 Cucurbita pepo  133, 259, 373
 Cultivars  8, 39, 41, 52, 116, 123, 137, 140, 149, 152, 169, 180, 183, 199,
 206, 228, 243, 268, 271, 273, 316, 324, 328, 334, 336, 340, 356, 357, 362, 363,
 364, 365, 379, 386, 403
 Cultivation  112, 343, 419
 Cultivation methods  309
 Cultural control  8, 13, 99, 137, 189, 203, 207, 210, 286, 299, 333, 355, 356,
 361, 368, 412, 418
 Cultural methods  358
 Cultural weed control  35, 42, 55, 224, 237, 330, 416
 Cyanazine  35, 45, 59
 Cyanobacteria  106
 Cycling  25, 78, 125, 294, 400
 Cyprus  148, 156
 Daucus carota  333, 414
 Decision making  36, 91, 113, 217, 348, 369
 Decomposition  25, 131, 179, 252, 256, 293, 294, 315, 392, 406, 413
 
 Degradation  26
 Delaware  280
 Delia platura  201, 346
 Denitrification  79, 81, 160, 222
 Density  48, 107
 Depth  73
 Dernopodzolic soils  279
 Desiccation  52
 Diabrotica barberi  86, 159
 Diammonium phosphate  429
 Diapause  86, 159
 Diaporthe phaseolorum  189
 Dicamba  34, 45, 95, 186
 Dichlormid  35
 Digitaria sanguinalis  330
 Direct sowing  35
 Discing  56, 393
 Disease control  3, 18, 99, 129, 137, 355
 Disease course  355
 Disease models  14, 80
 Disease prevalence  71, 189, 275, 286
 Disease resistance  137, 203, 228, 273
 Disease surveys  15, 80, 197, 333
 Distribution  216
 Ditylenchus destructor  152, 374
 Ditylenchus dipsaci  116
 Double cropping  73, 75, 113, 205, 240, 280, 352, 371
 Drills  150
 Drought  417
 Drought injury  164
 Dry beans  235
 Dry conditions  384
 Dry farming  69, 75, 89, 182, 199
 Dry matter  17, 21, 99, 258, 261, 341, 365, 384
 Dry matter accumulation  5, 42, 43, 56, 78, 111, 172, 182, 183, 218, 289, 295,
 296, 317, 319, 336, 397
 Duplex soils  64, 163
 Duration  303
 Dwarf cultivars  19
 Dynamics  282
 Earliness  262
 Earthworms  89, 125, 193
 Echinochloa crus-galli  42
 Econometric models  332
 Economic analysis  93, 162, 198, 230
 Economic impact  165
 Economic thresholds  370
 Economic viability  92
 Ecosystems  125, 141
 Edaphic factors  26, 313
 Efficacy  416
 Electrical conductivity  78
 Eleusine indica  330
 Emergence  63, 363
 Endogone  155
 England  257, 342
 Environmental factors  42, 83, 131, 363
 Environmental impact  91, 165, 184, 253
 Environmental temperature  86, 255
 Enzyme activity  238, 294
 Epidemiology  80, 376
 Eptc  35, 215, 326
 Equations  148
 Eragrostis cilianensis  330
 Erodibility  380
 Erosion  9, 36, 44, 154, 165, 233, 260, 381, 390
 Erosion control  56, 309, 383, 425
 Establishment  42, 119, 214
 Estimation  22, 24, 144, 145, 146, 148
 Ethephon  149
 Evaluation  150, 217
 Evapotranspiration  50, 69
 Ewes  409
 Experimental design  270
 Experimental stations  185
 Expert systems  85, 217
 Extraction  5
 Factors of production  206
 Fagopyrum  275
 Fagopyrum esculentum  42, 129, 318
 Fagopyrum tataricum  42
 Fallow  43, 52, 63, 100, 101, 112, 138, 140, 160, 180, 298, 347, 351, 382, 384,
 401, 409
 Fallow systems  76, 120, 139, 378
 Farm budgeting  2, 91, 144, 145, 146, 367
 Farm comparisons  40, 168
 Farm enterprises  91
 Farm income  94
 Farm inputs  94, 168, 308
 Farm machinery  168
 Farm management  68, 91, 93, 113, 217
 Farm planning  217, 297
 Farm results  94, 332
 Farm size  94
 Farmers' attitudes  184
 Farming  380
 Farming systems  84, 93, 164
 Farming systems research  56
 Farmland  68, 401
 Farmyard manure  29, 265, 404
 Fats  183
 Feasibility  184
 Fecundity  278
 Federal programs  36, 113, 234
 Feeding behavior  305
 Feeding preferences  173
 Fertility  328
 Fertilizer placement  60
 Fertilizer requirement determinatio  60, 284
 Fertilizer requirement determination  92, 251, 264, 271, 281, 328, 349, 351,
 397, 405
 Fertilizers  49, 100, 101, 102, 103, 143, 239, 268, 279, 324, 362, 390, 405
 Festuca  140
 Festuca arundinacea  155
 Field capacity  352
 Field crops  17, 266
 Field experimentation  141, 154, 266
 Field tests  20, 147
 Finite element analysis  82
 Flood irrigation  144, 145, 146, 367
 Flooded rice  179, 241
 Flooding  107, 160
 Florida  232, 242, 277, 295, 352
 Fluazifop  307
 Fodder crops  209, 252, 378
 Fomesafen  191
 Food composition  83
 Food research  83
 Forage  215, 295
 Foraging  173
 Formation  88
 France  24
 Fruits  223, 262
 Fumigation  140
 Fungal diseases  15, 18, 63, 137, 196, 207
 Fungicides  3, 273, 355
 Fungus control  124, 163, 192, 342, 366, 412
 Furrow irrigation  174, 293
 Fusarium  185, 197, 207
 Fusarium solani f.sp. phaseoli  121, 122
 Gaeumannomyces graminis  14, 71, 163, 196, 311
 Genetic improvement  83
 Genetic resistance  228
 Genotype environment interaction  363
 Genotypes  52, 428
 Geocoris punctipes  48
 Geographical distribution  171
 Georgia  48, 62, 185, 243, 353, 379
 Germination inhibitors  414
 Gibberella avenacea  196
 Gibberella pulicaris  196
 Gibberella zeae  196, 376
 Gley soils  279
 Glycine max  1, 5, 8, 10, 16, 24, 25, 26, 28, 31, 34, 40, 44, 47, 50, 54, 56,
 61, 67, 69, 70, 71, 73, 74, 75, 76, 79, 80, 82, 84, 85, 90, 91, 92, 93, 94,
 104, 105, 115, 121, 123, 132, 134, 135, 136, 140, 141, 144, 145, 146, 149, 155,
 159, 164, 165, 168, 169, 172, 176, 185, 189, 197, 198, 201, 205, 206, 207, 209,
 211, 213, 229, 232, 236, 237, 239, 242, 243, 245, 249, 250, 251, 253, 254, 255,
 260, 263, 277, 280, 281, 282, 284, 290, 291, 292, 295, 301, 304, 307, 312, 313,
 319, 321, 324, 331, 332, 334, 335, 336, 337, 339, 340, 346, 351, 352, 353, 354,
 356, 357, 358, 359, 360, 361, 362, 363, 364, 365, 366, 367, 368, 369, 371, 373,
 375, 376, 381, 386, 387, 388, 389, 391, 393, 394, 395, 396, 405, 410, 415, 418
 Glyphosate  45, 55, 95, 186, 291, 347, 416
 Gossypium  53, 54, 63, 246, 310, 332
 Gossypium hirsutum  26, 45, 51, 52, 78, 126, 134, 142, 186, 192, 236, 245, 283,
 360, 370
 Grain  19, 25, 44, 55, 58, 61, 66, 75, 100, 107, 111, 120, 132, 161, 180, 207,
 212, 218, 221, 250, 291, 295, 317, 321, 336, 351, 354, 377, 384, 397, 402, 405,
 410
 Gram negative bacteria  99
 Gramineae  49
 Grasses  33, 64, 184, 270, 401
 Green manure crops  219, 220
 Green manures  20, 23, 29, 39, 49, 84, 100, 101, 102, 103, 106, 107, 108, 109,
 110, 112, 117, 131, 143, 147, 153, 157, 158, 160, 162, 166, 167, 178, 179, 180,
 181, 182, 193, 223, 233, 240, 241, 247, 252, 256, 258, 265, 269, 274, 287, 288,
 289, 294, 296, 308, 314, 315, 325, 327, 329, 345, 350, 372, 378, 382, 383, 398,
 404, 406, 407, 411, 413
 Green manuring  220
 Greenhouse crops  152
 Ground cover  215, 371
 Groundwater pollution  82, 253, 254
 Growth  24, 107, 110, 156, 176, 221, 384, 423
 Growth rate  11, 58, 66, 76, 181, 182, 183, 289, 316, 336
 Growth retardation  267
 Growth stages  70, 291
 Guyana  98
 Gypsum  72
 Hapludults  388, 389
 Harrowing  212
 Harvest index  118, 183, 365
 Harvesting  84, 108, 177, 273, 362
 Harvesting date  299
 Hay  20, 261, 287, 419
 Heavy metals  5, 105
 Helianthus annuus  24, 34, 74, 96, 191, 255, 295, 318
 Helicotylenchus  275
 Herbage  180
 Herbicide application  37, 45
 Herbicide mixtures  191, 307, 326, 360, 402
 Herbicide rates  96, 307
 Herbicide recommendations  307
 Herbicide residues  16, 32, 34, 37, 95, 96, 97, 126, 136, 209, 318, 326, 359,
 402
 Herbicide resistance  417
 Herbicides  3, 26, 28, 53, 94, 115, 208, 209, 210, 291, 307, 343, 369, 373,
 375, 398, 417, 418, 419, 420
 Heterodera glycines  8, 47, 123, 169, 229, 339, 340, 356, 357, 358
 
 Hevea  230
 Hibiscus cannabinus  337
 High volume spraying  291
 Highlands  269
 Hirschmanniella mucronata  276, 407
 Hirschmanniella oryzae  276, 407
 Historic sites  266
 Historical records  266
 History  9, 36, 83
 Hoeing  212, 237
 Hoplolaimus columbus  236
 Hordeum vulgare  17, 19, 30, 32, 66, 71, 88, 95, 96, 111, 148, 156, 161, 197,
 204, 238, 267, 270, 279, 293, 294, 302, 303, 314, 333, 350, 378, 409, 427
 A horizons  100, 101
 Horizons  279
 Host parasite relationships  152, 169
 Host preferences  278, 305
 Host specificity  267, 379
 Hosts of plant diseases  286
 Hosts of plant pests  152, 333, 374
 Humid tropics  27, 258, 281, 282
 Humus  294
 Hybrids  261, 329, 379
 Hydraulic conductivity  82, 107, 226
 Hydrolysis  406
 Idaho  157, 267, 293, 423
 Illinois  11, 86, 115, 135, 159, 168, 260, 266, 359, 381
 Imazapyr  186
 Imazaquin  135, 191, 211, 359, 360
 Imazethapyr  135, 245, 326, 359, 360
 Imidazolinone herbicides  134
 Immobilization  81, 274, 320
 Importation  300
 Improved fallow  170
 In vitro digestibility  295
 Incentives  162, 331
 Incidence  14, 71, 80, 129, 140, 189, 196, 197, 207, 286, 311, 376
 
 Incorporation  11, 52, 81, 107, 117, 222, 294, 346, 351, 353
 Indexes  203, 351
 India  29, 106, 143, 222, 265, 400
 Indian punjab  107, 167, 225, 406
 Indiana  94, 206, 208, 357
 Indicator plants  110
 Indigofera hirsuta  173, 278, 340
 Indigofera tinctoria 3258
 Indonesia  228
 Infection  76
 Infections  14, 71
 Infectivity  122
 Infestation  63, 116
 Infiltration  72, 107, 353, 387
 Innovation adoption  113, 260
 Inoculum  99, 376
 Inoculum density  63, 71, 80, 122, 286, 376
 Inorganic salts  288
 Insect control  3, 48, 309
 Insect pests  299, 309, 379
 Insect repellents  173
 Insect traps  346
 Insecticide application  309
 Insecticides  3
 Insects  3
 Integrated control  35, 231
 Integrated pest management  3, 94
 Intensive production  223
 Interactions  131, 311, 314, 363, 364, 384
 Intercropping  48, 66, 84, 171, 200, 202, 228, 233
 Interest rates  113
 Interplanting  149, 215
 Interrow cultivation  237
 Interspecific competition  200
 Introduced species  89
 Ion uptake  5
 Iowa  40, 56, 92, 93, 105, 264, 324, 354, 375, 396, 405
 Iprodione  342
 Irrigated conditions  75, 107, 205, 331
 Irrigated soils  16, 72, 225
 Irrigation  69, 78, 143, 194
 Irrigation requirements  217
 Irrigation water  4, 72, 78, 216, 348
 Isolation  207
 Isotope labeling  30, 147, 241
 Isotopes  156, 250
 Isotypes  19
 Japan  79
 Kansas  67, 104, 113, 331
 Kentucky  155, 218, 221, 226, 377
 Kenya  127
 Kernels  112, 302
 Labeling  17, 239
 Labor costs  93
 Labor requirements  91, 93
 Lactuca sativa  42, 99
 Lambs  409
 Land  93
 Land productivity  84
 Landscape  380
 Lathyrus sativus  409
 Lathyrus tingitanus  166, 296
 Leachates  11
 Leaching  6, 27, 38, 40, 158, 160, 251, 280, 293, 306, 402
 Lead  105
 Leaf area  21, 341
 Leaf area index  183
 Leaf duration  183
 Leaves  25, 256, 315
 Legislation  162
 Legumes  4, 64, 83, 127, 166, 178, 182, 184, 196, 199, 200, 219, 220, 247, 252,
 258, 270, 289, 308, 344, 422, 425, 426
 Leguminosae  49, 110, 170, 186, 190, 256, 315, 325, 332, 372
 Lens culinaris  15, 32, 34, 38, 95, 96, 166, 267, 296, 302, 318, 413, 423, 427
 Lentils  274, 345
 Leptosphaeria nodorum  71, 376
 Lespedeza cuneata  5
 Lespedeza stipulacea  313
 Lespedeza striata  5
 Life cycle  357, 358, 361
 Light intensity 215
 Light penetration  224
 Light relations  214
 Light transmission  149
 Lignin  25, 256
 Lime  27, 230, 268
 Linear models  290
 Linear programming  94, 217
 Linum usitatissimum  32, 34, 137, 138, 139, 318
 Literature reviews  64, 143, 200, 229, 247, 252, 396
 Live mulches  221, 256, 263, 373
 Liveweight gain  409
 Loam soils  56, 144, 145, 146, 216, 282, 294, 367, 405
 Lodging  363
 Lolium multiflorum  42, 43, 81, 134, 333
 Lolium perenne  116, 314
 Long term experiments  6, 7, 44, 66, 92, 100, 101, 105, 154, 266, 354, 382,
 389, 429
 Longevity  379
 Losses from soil  25, 27, 64, 158, 274, 392, 394, 395
 Losses from soil systems  222, 247, 289, 321, 381, 401, 413
 Lotus corniculatus  287
 Louisiana  184, 213, 307, 337, 361
 Low input agriculture  184, 262, 416
 Low volume spraying  291
 Lowland areas  181, 404
 Lupins  77, 83, 323
 Lupinus  6, 7, 124, 210, 231
 Lupinus albus  129, 142, 183, 248, 428
 Lupinus angustifolius  21, 30, 128, 183, 248, 428, 429
 Lupinus luteus  183
 Lupinus mutabilis  183, 269
 Lupinus varius  428
 Lycopersicon esculentum  259, 262, 288, 373, 414
 Lygus lineolaris  379
 Machinery requirements  91
 Macrophomina phaseolina  202
 Macropores  226
 Magnesium  27, 31, 230, 405
 Magnesium chloride  72
 Maine  129, 271, 275, 328
 Maize  36, 68, 127, 168, 217, 332
 Maize silage  317
 Maize stover  119, 221
 Malaysia  230, 300
 Malting barley  19
 Malting quality  19
 Management 108
 Manganese  268
 Manitoba  318
 Manual weed control  212
 Market prices  36, 113
 Maryland  43, 161, 224, 262, 280, 298, 330, 425
 Mathematical models  78, 94, 113, 147, 311, 396
 Mato grosso do sul  376
 Maturation  52, 363, 364
 Maturation period  261
 Maturity  149, 262
 Maturity groups  123
 Maturity stage  271
 Maximum yield  272
 Meadows  93
 Measurement  148, 352
 Mechanical methods  237
 Medicago sativa  11, 17, 32, 35, 66, 71, 78, 91, 95, 97, 100, 101, 103, 104,
 105, 108, 118, 119, 120, 130, 131, 153, 157, 161, 164, 165, 171, 180, 198, 201,
 215, 223, 244, 261, 264, 283, 293, 294, 296, 297, 303, 329, 347, 348, 349, 351,
 374, 417, 424
 Medicago truncatula  41, 177
 Mediterranean climate  183
 Melilotus  287, 378
 Melilotus alba  313
 Melilotus officinalis  100, 101, 102, 117, 161, 180, 215, 250, 251, 321
 Meloidogyne arenaria  8, 13, 51, 65, 187, 338, 339, 340, 356, 366, 412
 Meloidogyne hapla  275, 333
 Meloidogyne incognita  65, 133, 187, 232, 242, 243, 277
 Meloidogyne javanica  133, 187
 Mesocotyls  207
 Metalaxyl  364
 Methodology  217
 Metolachlor  211, 307, 326, 402
 Metribuzin  136, 191, 211, 360
 Michigan  97, 171, 287, 303
 Microbial activities  303, 312, 344
 Microbial pesticides  288
 Microeconomic analysis  91, 165
 Microenvironments  224
 Midi pyrenees  217
 Milk production  409
 Mine tailings  295
 Mineral content  292, 295
 Mineral uptake  292
 Mineralization  4, 10, 25, 38, 81, 100, 101, 102, 103, 131, 143, 158, 239, 247,
 256, 274, 293, 314, 320, 350, 351
 Minimum tillage  28, 66, 71, 135, 139, 163, 174, 243, 373, 401
 Minimum tillage systems  73
 Minnesota  50, 70, 91, 189, 237, 336, 351, 363, 364, 393, 396
 Mississippi  75, 80, 126, 134, 246, 358, 371, 426
 Missouri  55, 154, 209, 266, 360, 415
 Mixed infections  333
 Models  198, 351, 420
 Moisture  140
 Moldboards  174, 363, 364, 386, 393
 Mollisols  105
 Mollugo verticillata  330
 Monoculture  8, 44, 50, 75, 249, 250, 251, 321, 336, 366
 Montana  20, 72, 96, 108
 Motad  332
 Movement in soil  82, 130, 254, 280
 Mucuna aterrima  27, 258
 Mucuna cochinchinensis  300
 Mucuna deeringiana  399
 Mucuna pruriens  399
 Mulches  63, 233, 262, 373
 Mulching  115
 Mutants  19
 Mycorrhizal fungi  155
 Mycorrhizas  155, 175, 391
 Mycosphaerella graminicola  71
 Natural enemies  299
 Natural regeneration  316
 Nebraska  69, 132, 136, 149, 174, 176, 249, 250, 251, 290, 320, 321, 417
 Neem cake coated urea  106
 Nematicides  3, 273, 357, 358, 368
 Nematoda  3, 244, 273, 334, 368
 Nematode control  3, 8, 13, 47, 65, 152, 187, 229, 232, 236, 243, 276, 333,
 340, 356, 357, 358, 361, 366, 368, 407, 412
 Nematode infections  374
 Nepal  325
 Nevada  424
 New Jersey  373
 New products  83
 New South Wales  16, 64, 120, 128, 210, 422
 New York  224
 Nickel  105
 Nicotiana tabacum  65, 140
 Nigeria  299
 Night temperature  214
 Nitrate  81, 158, 222
 Nitrate nitrogen  27, 56, 120, 160, 251, 271, 293, 320, 321, 349, 405
 Nitrates  6, 82, 130
 Nitrates (inorganic salts)  377
 Nitrogen  10, 17, 25, 43, 56, 57, 67, 81, 100, 101, 102, 103, 117, 120, 147,
 148, 156, 157, 158, 166, 171, 182, 195, 221, 222, 239, 241, 249, 250, 251, 253,
 254, 256, 259, 260, 265, 268, 274, 287, 289, 293, 314, 315, 319, 320, 321, 324,
 345, 350, 351, 377, 382, 383, 389, 392, 397, 403, 405, 411, 422
 Nitrogen balance  158
 Nitrogen content  21, 99, 132, 161, 172, 180, 182, 218, 250, 255, 259, 269,
 287, 292, 303, 316, 317, 319, 328, 329, 341, 349, 392, 426
 Nitrogen cycle  81, 143, 247, 294, 392
 Nitrogen fertilizers  4, 19, 21, 30, 31, 40, 43, 54, 118, 124, 125, 141, 148,
 156, 172, 177, 178, 184, 193, 199, 205, 218, 221, 233, 237, 246, 247, 248, 249,
 250, 251, 255, 258, 264, 271, 287, 292, 302, 304, 306, 308, 309, 317, 321, 328,
 331, 332, 341, 349, 350, 377, 397, 410, 427
 Nitrogen fixation  17, 22, 30, 38, 57, 114, 147, 148, 170, 181, 182, 195, 200,
 241, 247, 252, 296, 325, 365, 372, 425
 Nitrogen fixing trees  49, 315
 Nitrogen mineralization  166
 Nitrogen recovery  180, 303
 Nitrogen residual effects  303
 Nitrogen uptake  111, 120, 161, 180, 303
 No-tillage  25, 31, 35, 44, 45, 55, 57, 58, 61, 67, 71, 88, 90, 94, 97, 98,
 115, 119, 130, 135, 136, 139, 146, 161, 168, 201, 207, 208, 209, 211, 212, 218,
 221, 226, 238, 246, 260, 261, 262, 280, 291, 293, 298, 317, 320, 330, 344, 347,
 352, 363, 364, 373, 377, 383, 386, 387, 388, 389, 392, 393, 394, 395, 401, 405,
 415, 416, 417, 420, 421, 423
 Nodulation  372
 North Carolina  1, 25, 45, 47, 140, 169, 268, 273, 317, 344, 384, 419
 North Dakota  34, 182, 362
 Npk fertilizers  112
 Nutrient availability  10, 30, 56, 60, 131, 143, 158, 160, 172, 221, 222, 274,
 280, 283, 284, 289, 292, 293, 295, 315, 319, 349, 351, 354, 388, 392, 400, 405,
 422, 427
 Nutrient balance  260, 279
 Nutrient content  20, 56, 70, 100, 101, 172, 221, 280, 289, 292, 295, 349, 395,
 405
 Nutrient contents of plants  111
 Nutrient deficiencies  354
 Nutrient excesses  354
 Nutrient nutrient interactions  292
 Nutrient removal by plants  218, 284, 303
 Nutrient requirements  283, 321, 410
 Nutrient sources  392
 Nutrient transport  221
 Nutrient uptake  56, 76, 156, 158, 172, 182, 225, 249, 250, 251, 259, 265, 271,
 274, 280, 287, 289, 292, 313, 314, 317, 319, 321, 329, 351, 397
 Nutrients  43, 70, 289, 395
 Oats  36
 Ohio  31, 44, 82, 207, 346, 416
 Oil palms  300
 Oklahoma  12, 186, 266, 309, 343, 355, 401
 Oligochaeta  89
 Ontario  28, 39, 66, 71, 90, 118, 121, 122, 365
 Operating costs  92
 Optimization  332
 Oregon  240
 Organic farming  84, 125, 273
 Organic fertilizers  9, 179, 219, 220
 Organic matter in soil  67, 120, 131
 Ornamental woody plants  33
 Oryza rufipogon  213
 Oryza sativa  22, 79, 80, 106, 107, 109, 112, 134, 143, 145, 160, 178, 179,
 181, 193, 194, 195, 212, 213, 239, 241, 245, 247, 276, 284, 307, 325, 327, 372,
 404, 407
 Ova  86
 Oversowing  301
 Overwintering  222
 Oviposition  346
 Oxisols  27, 60, 230, 258, 272, 284
 Pacific northwest states of U.S.A.  150
 Pacific states of U.S.A.  244
 Paddy soils  147
 Pakistan  315
 Paleudults  63
 Panicum miliaceum  35
 Parana  376
 Paraquat  45, 52, 291
 Parasites of insect pests  299
 Paratrichodorus  277
 Paratrichodorus minor  243
 Paratylenchus  275
 Particle size  88
 Particle size distribution  88, 105
 Paspalum notatum  8, 18, 338
 Pathogenicity  267
 Peanut oil  112
 Pendimethalin  35, 211, 212, 326
 Penetrometers  352
 Pennisetum Americanum  265
 Pennsylvania  119
 Perennial weeds  186
 Performance  363, 364
 Performance testing  150
 Persistence  16, 26, 32, 34, 41, 97, 135, 186, 191, 209, 245, 294, 318, 360,
 402
 Peru  281, 282
 Pest control  375
 Pest management  12, 51, 62, 338
 Pest resistance  8, 169, 243, 244, 334, 357
 Pesticidal action  193
 Pesticide persistence  96
 Pesticides  130, 165, 273, 375
 Petioles  271
 Phalaris arundinacea  81
 Phaseolus  194
 Phaseolus vulgaris  14, 32, 37, 90, 121, 122, 153, 174, 191, 205, 259, 326,
 373, 374, 385, 420
 Phenology  29
 Phialophora gregata  189
 Philippines  147, 160, 178, 179, 193, 212, 247, 327, 404
 Phleum pratense  154, 204, 333
 Phosphates  199
 Phosphatic clay  295
 Phosphogypsum  72
 Phosphorus  25, 31, 49, 76, 92, 131, 260, 289, 294, 344, 400, 401, 405
 Phosphorus fertilizers  60, 92, 167, 225, 272, 400, 401, 409, 423
 Phosphorus residual effect  272
 Physico-chemical properties of soil  73
 Physicochemical properties  294, 312
 Phytophthora  364
 Phytotoxicity  5, 11, 16, 26, 34, 95, 96, 97, 134, 135, 186, 211, 318, 326,
 398, 399, 402
 Pig slurry  288
 Pisum sativum  2, 32, 37, 95, 111, 129, 131, 137, 138, 139, 150, 153, 157, 161,
 177, 203, 223, 257, 267, 286, 296, 302, 311, 313, 314, 318, 342, 409, 423, 427
 Plant analysis  70, 100, 271, 280, 281, 405
 Plant breeding  83, 252
 Plant competition  200, 215
 Plant composition  25, 256, 271, 287, 349
 Plant density  41, 126
 Plant disease control  46, 140, 189, 203, 228, 273, 286, 288, 364
 Plant diseases  3, 273
 Plant disorders  207
 Plant extracts  173
 Plant height  149, 261, 363, 364, 386
 Plant nutrition  110, 205, 230, 255
 Plant parasitic nematodes  65, 169, 197, 204, 275, 333, 361, 370
 Plant pathogenic bacteria  137
 Plant pathogenic fungi  129, 197, 203, 376
 Plant pathogens  153
 Plant proteins  302
 Plant residues  131, 330
 Plant tissues  207
 Plant water relations  50, 296
 Plantations  33, 300
 Planting  84, 280
 Planting date  35, 115, 123, 182, 206, 237, 261, 262, 299, 346, 393
 
 Plants  289
 Plastic film  223
 Plowing  44, 76, 88, 97, 129, 130, 135, 174, 177, 207, 208, 212, 238, 330, 363,
 364, 386, 393, 405, 420
 Poa compressa  415
 Polyphenols  256
 Population density  63, 89, 104, 121, 123, 152, 197, 201, 208, 236, 242, 275,
 276, 277, 278, 330, 333, 346, 366, 379
 Population distribution  89
 Population dynamics  121, 208, 211, 370, 420
 Population growth  305
 Populations  62, 123
 Pore size distribution  72
 Pores  160
 Porosity  72, 222
 Potassium  27, 31, 92, 279, 280, 281, 282, 283, 289, 354, 405
 Potassium chloride  280
 Potassium fertilizers  49, 92, 167, 281, 282, 284, 354, 423
 Potatoes  68, 285
 Poultry manure  294
 Pratylenchus  242, 277
 Pratylenchus brachyurus  243
 Pratylenchus crenatus  275
 Pratylenchus penetrans  204, 275, 333
 Pratylenchus scribneri  104
 Precipitation  89, 171, 182, 221, 255, 280
 Predators of insect pests  48, 299
 Predicted difference  290
 Prediction  158
 Preplanting treatment  221, 326
 Prescribed burning  210
 Prince edward Island  196, 197, 204, 333
 Product development  83
 Production  85
 Production costs  36, 40, 57, 90, 92, 93, 113, 144, 145, 146, 217, 293, 367
 Profiles  221
 Profitability  92, 93, 162, 198, 297, 298, 331, 354
 Profits  91, 348
 Program evaluation  234
 Program participants  36, 40
 Projections  168
 Prometon  402
 Protein  112
 Protein content  183, 295
 Protein sources  83
 Pseudomonas  185
 Pseudomonas cepacia  288
 Pseudomonas fluorescens  288
 Pseudomonas gladioli  288
 Pseudomonas solanacearum  46, 140, 228, 288
 Psophocarpus tetragonolobus 141
 Puddling  107
 Pueraria  300
 Pyrenophora tritici-repentis  71
 Pythium  133, 185, 267
 Pythium irregulare  267
 Pythium ultimum  267
 Quality  238
 Quantitative analysis  252
 Quebec  238
 Queensland  114
 Radioactive tracers  250, 303
 Radium  295
 Rain  6, 56, 98, 121, 207, 215, 216, 304, 311, 349, 381
 Reclamation  5, 72
 Record keeping  3
 Recovery  43, 225, 249, 250, 251
 Recycling  289
 Red clay soils  120
 Red soils  128
 Reduction  81
 Regressions  348
 Regrowth  42
 Relay cropping  200
 Repellents  1
 Reproductive performance  317
 Research projects  266
 Residual effects  26, 37, 59, 92, 95, 96, 107, 112, 134, 135, 143, 186, 245,
 247, 257, 320, 321, 326, 359, 360, 377, 400, 404
 Resistance to penetration  352
 Resowing  58, 59, 317
 Respiration  100, 102, 312
 Responses  70, 363, 364
 Returns  36, 90, 91, 92, 93, 113, 162, 184, 261, 293, 297, 331, 332, 354
 Reviews  22, 372
 Rhizobiaceae  252
 Rhizobium  84, 372
 Rhizoctonia cerealis  196
 Rhizoctonia solani  63, 80, 129, 133, 189, 192, 196, 197
 Rhizosphere  185, 288
 Rice  68
 Rice soils  193, 411
 Rice straw  406
 Ricinus communis  338
 Ridging  56, 76, 363, 364, 393, 405
 Rio grande do sul  376
 Risk  36, 113, 184, 331
 Risks  91, 332
 Rock phosphate  429
 Root rots  124, 153, 196, 197, 203, 364
 Roots  11, 25, 76, 99, 107, 176, 333, 399
 Rotary cultivation  174
 Rotary hoes  237
 Rotation  28, 47, 100, 127, 166, 229, 233, 236, 239, 270, 368
 Rotations  1, 2, 3, 4, 6, 7, 8, 10, 11, 13, 14, 15, 16, 17, 18, 19, 24, 26, 30,
 31, 32, 34, 35, 36, 37, 38, 40, 41, 44, 46, 50, 51, 54, 56, 60, 61, 62, 63, 64,
 65, 66, 67, 68, 69, 70, 71, 73, 74, 75, 76, 77, 78, 79, 80, 82, 83, 88, 89, 90,
 91, 92, 94, 95, 96, 97, 98, 101, 102, 103, 104, 105, 107, 111, 112, 114, 116,
 118, 120, 121, 122, 123, 124, 128, 129, 130, 132, 134, 135, 136, 137, 138, 139,
 140, 141, 144, 145, 146, 148, 149, 150, 152, 154, 155, 156, 160, 162, 163, 164,
 165, 170, 172, 174, 176, 177, 180, 185, 186, 187, 189, 191, 194, 196, 197, 198,
 199, 202, 203, 204, 205, 206, 207, 208, 209, 210, 211, 213, 217, 228, 231, 232,
 234, 235, 237, 238, 242, 243, 244, 245, 248, 249, 250, 251, 253, 254, 255, 257,
 260, 264, 266, 267, 268, 271, 272, 273, 275, 276, 277, 279, 280, 283, 284, 286,
 287, 290, 292, 293, 295, 297, 298, 302, 303, 304, 307, 308, 311, 312, 318, 319,
 321, 324, 326, 328, 331, 332, 333, 334, 335, 336, 337, 338, 339, 340, 342, 344,
 347, 349, 350, 351, 352, 354, 355, 356, 357, 358, 359, 360, 361, 362, 363, 364,
 365, 366, 370, 374, 375, 376, 378, 382, 386, 387, 388, 389, 391, 393, 394, 395,
 396, 400, 401, 402, 403, 405, 407, 409, 410, 412, 417, 418, 419, 422, 424, 427,
 428, 429
 Row orientation  58, 84, 215
 Row spacing  1, 35, 84, 206, 211, 237, 393
 Rowcrops  215
 Rsfsr  279
 Rubber plants  300
 Runoff  44, 165, 260, 381, 394, 401
 Runoff water  395
 Rwanda  170
 Saccharum officinarum  84
 Safety  419
 Saline soils  72
 Saline water  78, 348
 Salinity  78
 Salt tolerance  23, 78
 Salts in soil  216
 Sampling  207
 Sandy loam soils  6, 63, 90, 222, 225, 279, 282, 318, 387
 Sandy soils  107, 216, 231, 280, 311, 352, 384
 Saprophytes  376
 Saskatchewan  15, 38, 100, 101, 102, 103, 137, 138, 139, 274, 296, 302, 345,
 382, 427
 Saturated conditions  22, 222
 Sclerotia 80
 Sclerotinia minor  355
 Sclerotinia sclerotiorum  342
 Scotland  314
 Screening  155, 343, 398
 Seasonal cropping  410
 Seasonal fluctuations  120, 274, 320, 345
 Seasonal growth  56, 182
 Seasonal variation  56, 61, 63, 89, 92, 99, 162, 171, 215, 349, 380, 405
 Secale cereale  12, 31, 42, 43, 55, 56, 90, 99, 115, 119, 142, 161, 201, 218,
 224, 226, 232, 243, 278, 279, 309, 330, 332, 341, 373, 377, 394, 395
 Seed banks  28, 208, 224, 420
 Seed dispersal  316
 Seed germination  11, 224, 237, 317, 347, 364
 Seed longevity  347
 Seed mixtures  215
 Seed moisture  386
 Seed production  244
 Seed purity  300
 Seed quality  300, 302, 362, 364
 Seed size  302
 Seed sources  1
 Seed treatment  362, 364
 Seed weight  302
 Seedbeds  371
 Seedling emergence  261, 326, 364
 Seedling growth  138
 Seedlings  97, 267, 364
 Seeds  41, 52, 75, 141, 189, 211, 255, 300, 316, 317, 363, 364, 365, 427
 Selectivity  398
 Semiarid climate  107, 182
 Semiarid soils  265, 400
 Sequential cropping  11, 26, 66, 97, 114, 141, 154, 172, 186, 212, 245, 259,
 292, 302, 319, 321, 336, 360, 366, 386, 387, 404, 410, 427
 Sesbania  147, 160, 179, 181, 193, 241, 276, 327, 404, 407
 Sesbania aculeata  106, 107, 167, 406
 Sesbania bispinosa  23
 Sesbania cannabina  147, 178
 Sesbania exaltata  173, 278
 Setaria faberi  55, 115, 208, 211
 Setaria viridis  214
 Sewage sludge  9, 294
 Shade  214
 Shoots  11, 25
 Shrubs  252
 Siberia  378
 Sieving  155
 Silt loam soils  26, 43, 105, 109, 136, 221, 222, 226
 Simazine  35, 59
 Simulation  381
 Simulation models  24, 78, 82, 158, 165, 168, 217, 260, 348
 Site factors  79, 141, 350
 Site preparation  268, 362
 Size  328
 Slope  380
 Slopes  381
 Sodic soils  72
 Sodic water  216
 Sodium  216
 Soil  12, 394
 Soil acidity  5, 6, 7, 128
 Soil air  222
 Soil amendments  295, 315, 406
 Soil analysis  4, 5, 323, 349
 Soil bacteria  79
 Soil biology  125, 344, 350, 378
 Soil chemistry  31, 70, 117, 132, 258, 281, 282, 350, 411
 Soil compaction  352
 Soil conservation  68, 138, 363, 381, 390
 Soil degradation  64, 84, 88
 Soil density  72, 107, 352
 Soil depth  10, 67, 89, 100, 101, 160, 237, 280, 347, 349, 352, 405
 
 Soil enzymes  238, 294
 Soil fertility  9, 10, 27, 30, 31, 38, 42, 103, 110, 112, 120, 127, 147, 157,
 160, 170, 171, 177, 179, 180, 185, 195, 241, 247, 266, 312, 328, 350, 378, 382,
 388, 422
 Soil flora  102, 155, 238, 265, 294, 312, 345
 Soil fumigation  124, 286
 Soil fungi  63, 155, 202
 Soil inoculation  114, 143, 252, 288, 365
 Soil management  12, 21, 88, 154, 230, 238, 252, 268, 341, 385
 Soil moisture  120
 Soil organic matter  9, 10, 74, 88, 100, 101, 103, 105, 107, 125, 128, 143,
 222, 238, 265, 269, 312, 318, 353, 382, 388, 389, 405
 Soil ph  6, 7, 32, 105, 216, 318, 388, 405
 Soil physical properties  31, 138, 142, 294, 350, 378, 387
 Soil pore system  222
 Soil properties  44, 128, 141, 143, 164
 Soil resources  268
 Soil sorption  131
 Soil strength  352
 Soil structure  66, 99, 294
 Soil temperature  16, 63, 98, 131, 224, 261, 267, 313, 386
 Soil test values  92, 354
 Soil testing  92, 253, 280
 Soil texture  222, 318
 Soil treatment  105, 294
 Soil types  206
 Soil types (physiographic)  61
 Soil variability  198
 Soil water  38, 98, 99, 119, 138, 214, 215, 261, 296
 Soil water content  50, 56, 58, 61, 88, 89, 107, 115, 119, 160, 221, 222, 224,
 280, 320, 352, 363, 384, 415
 Soil water movement  130
 Soil water potential  131
 Soil water regimes  353
 Soil water retention  107
 Soils  285
 Solanum tuberosum  32, 34, 96, 129, 167, 204, 269, 271, 275, 279, 286, 287,
 328, 333, 374
 Solenopsis invicta  173
 Solid wastes  9
 Solonetzic soils  378
 Sorghum  54, 113, 329
 Sorghum bicolor  11, 24, 26, 37, 42, 67, 73, 75, 104, 120, 132, 134, 176, 186,
 202, 205, 218, 232, 242, 245, 249, 250, 251, 277, 290, 291, 295, 304, 316, 321,
 337, 339, 353, 356, 360, 383, 387, 401
 Sorghum sudanense  232, 286
 Sorption isotherms  105
 South  Africa  152, 205
 South australia  64, 89, 177, 311
 South Carolina  52, 65, 368
 South Dakota  76, 86, 130, 234, 253, 254, 335, 391
 Southeastern states of U.S.A.  308
 Sowing  171
 Sowing date  95, 119, 161, 191, 199, 215, 245, 416
 Sowing depth  119
 Sowing rates  199
 Soybean  175
 Soybeans  36, 68, 113, 217
 Spacing  362
 Spain  183, 187
 Spatial distribution  97, 101, 363
 Spatial variation  171, 221, 363, 364
 Species  72, 89
 Species diversity  62
 Specific gravity  286, 328
 Spinacia oleracea  191
 Split dressings  205, 397
 Spoil heap soils  5
 Spore germination  155
 Spring  95
 Spring wheat  117
 Sprinkler irrigation  216
 Sri lanka  141, 241
 Stability  66, 74, 88, 107, 353, 380, 400
 Stand characteristics  182
 Statistical analysis  24
 Statistics  1, 206, 375
 Stellaria media  43, 415
 Stem nodules  181, 372
 Stems  207, 372
 Stochastic processes  36, 91, 184
 Stover  132, 250, 365
 Strains  207
 Straw  111, 274, 345
 Straw disposal  100
 Straw incorporation  345
 Streams  348
 Strip cropping  58
 Stubble  55, 210, 377
 Stubble cultivation  138, 139, 423
 Stubble mulching  401
 Subsoiling  352, 384
 Substitution  308
 Subsurface drainage  64
 Subtropical crops  252
 Subtropics  10
 Sulfonylurea herbicides  245
 Sulfur  294
 Sumatra  284
 Superphosphates  77, 323, 429
 Suppression  42, 214
 Surface layers  67, 101, 320, 353
 Surface modification  353
 Surface water  395
 Surveys  159, 346
 Survival  63, 86, 376, 379, 423
 Sustainability  12, 44, 56, 92, 94, 103, 125, 128, 139, 157, 162, 163, 164,
 195, 198, 200, 234, 266, 405
 Symbiosis  372
 Symptoms  355, 358, 368
 Syria  409
 Target prices  113
 Tebuthiuron  186
 Temperature  140, 214
 Temporal variation  52, 182, 207, 221, 237, 238, 280, 294, 363, 364
 
 Terbuthylazine  402
 Texas  401
 Thielaviopsis basicola  192, 310
 Tillage  1, 10, 21, 25, 42, 55, 61, 64, 66, 67, 71, 85, 90, 98, 117, 118, 119,
 125, 136, 137, 138, 168, 209, 210, 211, 226, 233, 235, 261, 270, 280, 293, 302,
 320, 335, 341, 347, 352, 360, 373, 377, 383, 385, 387, 388, 389, 390, 391, 392,
 393, 394, 396, 401, 418, 427
 Tilth  396
 Time  415
 Time series  184
 Timing  29, 117, 326, 397
 Tolerance  359
 Topsoil  27, 154
 Trace element deficiencies  429
 Traditional farming  184
 Trafficability  352
 Transformation  392, 400
 Transpiration  221
 Transplanting  160
 Treatment  343
 Trees  252
 Triasulfuron  318
 Trichoderma  207
 Trickle irrigation  216, 223
 Triclopyr  186
 Trifluralin  185
 Trifolium  275
 Trifolium alexandrinum  20, 108, 240, 316
 Trifolium brachycalycinum  379
 Trifolium hirtum  161
 Trifolium hybridum  197, 215
 Trifolium incarnatum  5, 25, 43, 45, 52, 57, 58, 59, 63, 142, 161, 232, 278,
 291, 313, 316, 317, 341, 353, 379, 384, 397, 410
 Trifolium pratense  5, 33, 39, 42, 66, 81, 88, 105, 154, 161, 171, 180, 197,
 204, 215, 238, 249, 250, 271, 279, 287, 321, 328, 329, 333, 374, 403
 Trifolium repens  116, 233, 313
 Trifolium resupinatum  108
 Trifolium subterraneum  161, 163, 248, 262, 291, 316, 373, 379
 Trifolium vesiculosum  161, 316
 Trifolium yanninicum  379
 Triticum  6, 7, 124, 128, 163, 177, 199, 206, 210, 231, 248, 257, 371, 422, 428
 Triticum aestivum  2, 10, 14, 24, 25, 32, 38, 53, 66, 69, 71, 73, 74, 75, 77,
 90, 94, 95, 96, 100, 101, 102, 103, 104, 107, 111, 117, 120, 126, 131, 134,
 136, 137, 138, 139, 144, 146, 150, 154, 157, 161, 164, 166, 171, 180, 186, 196,
 197, 205, 225, 239, 255, 265, 267, 274, 280, 286, 293, 298, 302, 311, 314, 323,
 325, 326, 328, 333, 337, 351, 359, 360, 376, 382, 386, 387, 388, 389, 393, 400,
 401, 423, 427, 429
 Tropical climate  265
 Tropical crops  252, 256
 Tropical soils  230, 256, 400
 Tropics  147
 Tubers  167, 271, 286, 287, 328
 Tubificidae  193
 Tylenchorhynchus  197, 275
 U.S.A.  68, 222
 U.S.S.R.in europe  279
 Udic regimes  387
 Udolls  92
 Uk  14
 Ultisols  230, 281, 282, 312
 Undersowing  149
 University research  332
 Upland rice  212, 284
 Upland soils  61
 Uptake  43, 239, 383
 Urea" 27, 160, 265, 406
 Urea fertilizers  105, 106, 179, 404
 Urea nitrates  258
 Use efficiency  56, 148, 397, 405
 Utilization  239
 Value theory  184, 217
 Variation  331
 Varietal reactions  52, 183, 271, 328, 363
 Varietal resistance  116, 140, 361
 Varietal susceptibility  364
 Varieties  1, 422
 Variety trials  1
 Vegetables  200, 343
 Vegetation management  45
 Verticillium albo-atrum  275
 Verticillium dahliae  275, 286
 Vesicular arbuscular mycorrhizas  76, 155, 176
 Vetch  53, 214
 Viability  300
 Vicia  161, 214, 218, 246, 316
 Vicia benghalensis  411
 Vicia faba  99, 172, 257, 292, 296, 302, 313, 319, 350, 427
 Vicia sativa  126, 148, 156, 161, 177, 379, 409
 Vicia villosa  12, 21, 43, 45, 52, 55, 56, 63, 81, 133, 142, 161, 180, 218,
 221, 222, 223, 224, 226, 262, 278, 287, 291, 298, 309, 310, 313, 320, 330, 377,
 392, 416
 Victoria  6, 7, 30, 41, 64, 422
 Vigna radiata  84, 404
 Vigna unguiculata  5, 29, 60, 98, 173, 202, 212, 258, 272, 278, 299, 370
 Vigor  364
 Virginia  216, 280
 Virulence  63
 Volatile compounds' 414
 Volatilization  4, 413
 Volunteer plants  317
 Washington  2, 19, 267, 286, 380
 Water availability  384
 Water conservation  221
 Water erosion  56, 394
 Water holding capacity  222
 Water management  69, 194
 Water pollution  165, 260
 Water quality  72, 78, 216
 Water stress  207
 Water use  296, 313, 348, 415
 Water use efficiency  50, 182, 199, 221
 Water, Underground  306
 Waterlogging  64
 Watersheds  394, 395, 401
 Weed biology  208, 420
 Weed competition  369
 Weed control  3, 26, 28, 32, 43, 55, 62, 94, 95, 115, 134, 135, 136, 163, 186,
 191, 208, 210, 211, 213, 214, 231, 245, 299, 308, 326, 347, 360, 362, 373, 375,
 398, 402, 417, 418, 419, 420, 425
 Weeding  212, 215
 Weeds  3, 42, 53, 62, 126, 215, 224, 237, 300, 330, 369, 373, 419, 421
 Weight  261, 363, 364
 Western australia  124, 163, 199, 231, 248, 428, 429
 Wetlands  143
 Wheat  68, 113, 345
 Wheat straw  131, 157, 265, 274
 Wilts  46, 140, 228, 288
 Winter  25, 43, 52, 99, 161, 316, 377, 410, 415
 Winter hardiness  423
 Winter wheat  107, 150, 171, 217, 293, 298
 Wisconsin  36, 211, 261, 349, 374, 386
 World markets  83
 Xanthium strumarium  55
 Yield components  19, 106, 180, 199, 327
 Yield increases  106, 427
 Yield losses  34, 236, 237, 311, 402, 416
 Yield response functions  225, 247, 248, 309, 335, 422
 Yields  93, 206, 365
 Zea mays  10, 16, 21, 24, 25, 27, 28, 29, 31, 35, 37, 39, 40, 43, 44, 45, 47,
 49, 50, 55, 56, 57, 58, 60, 61, 62, 66, 67, 69, 70, 71, 74, 75, 76, 78, 81, 82,
 85, 86, 90, 91, 92, 93, 94, 97, 98, 104, 105, 107, 110, 115, 118, 121, 130,
 134, 135, 136, 140, 141, 149, 154, 159, 161, 164, 165, 171, 172, 174, 185, 189,
 198, 201, 205, 206, 207, 208, 211, 212, 214, 215, 216, 218, 221, 226, 230, 232,
 233, 235, 237, 242, 245, 249, 250, 251, 253, 254, 255, 258, 259, 260, 261, 264,
 272, 277, 281, 282, 287, 290, 292, 293, 295, 298, 303, 304, 317, 318, 319, 320,
 321, 324, 330, 331, 335, 336, 339, 341, 344, 347, 348, 349, 351, 354, 359, 360,
 363, 364, 373, 374, 375, 377, 381, 384, 386, 388, 389, 391, 393, 394, 395, 396,
 397, 402, 403, 404, 405, 410, 416, 417, 418, 420
 Zimbabwe  402
 Zinc  105, 429
 Zinc fertilizers  429
 
  

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https://www.nal.usda.gov/afsic/AFSIC_pubs/qb94-13.htm, June 1994

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