DOCSLIB.ORG

Cotton Research Report

Total Page：16

File Type：pdf, Size：1020Kb

Download full-text PDF Read full-text
Cotton Research Report 2008 AU Crops Cotton Research Report Research Report No. 33 March 2009 Alabama Agricultural Experiment Station Richard Guthrie, Director Auburn University Auburn, Alabama Printed in cooperation with the Alabama Cooperative Extension System (Alabama A&M University and Auburn University) ACKNOWLEDGMENTS This publication is a joint contribution of Auburn University, the Alabama Agricultural Experiment Station, and the USDA Agri- cultural Research Service and Soil Dynamics Laboratory. Research contained in the AU crops research reports was partially funded through the Alabama Cotton Commission, the Wheat and Feed Grains Committee, the Alabama Soybean Producers, and private industry grants. All donations, including the Alabama Cotton Commission grants and private industry funding, are appreciated. CONFIDENTIAL REPORT Publication, display, or distribution of data contained herein should not be made without prior written approval. Mention of a trademark or product does not constitute a guarantee of the product by Auburn University and does not imply its approval to the exclusion of other products. This report can be found on the Web at http://www.ag.auburn.edu/aaes/communications/researchreports/08cottonrr.pdf Information contained herein is available to all persons regardless of race, color, sex, or national origin. Published by the Alabama Cooperative Extension System (Alabama A&M and Auburn universities) in cooperation with the U.S. Department of Agriculture. An equal opportunity educator and employer. CONTENTS page Editors, Contributors ...........................................................................................................................................................................5 VARIETY TRIALS Enhancing Cotton Variety Selection through On-Farm Evaluations, 2008 ........................................................................................7 Breeding Cotton for Yield and Quality in Alabama ............................................................................................................................8 Economic Consequences of Using Different Cotton Variety Technology Systems in Alabama ........................................................9 Screening Trials for Cotton Variety Resistance to Verticillium Wilt ................................................................................................12 CROP PRODUCTION Benefi ts of Uniform Row Spacing in a Cotton-Corn Conservation System .....................................................................................13 Effect of Premature Defoliation on Cotton Yield and Lint Quality in Southwest Alabama .............................................................16 Agronomic and Economic Impact of Timing for Planting and Defoliation of Cotton on Cotton Yield, Quality, and Profi tability ................................................................................................................................17 Evaluation of a CORS for Use by Alabama Producers .....................................................................................................................20 Evaluation of Variable-Rate Seeding for Cotton...............................................................................................................................21 The Old Rotation (circa 1896) – 2008 ..............................................................................................................................................22 The Cullars Rotation (circa 1911) – 2008 .........................................................................................................................................24 Impact of Crop Rotation on Diseases and Nematode Pests of Cotton, Corn, and Peanut as well as on the Economics of Cotton, Corn, and Peanut Production .....................................................................................25 IRRIGATION Sprinkler Irrigation for Site-Specifi c, Precision Management of Cotton .........................................................................................27 Subsurface Drip Irrigation Fertigation for Site-Specifi c, Precision Management of Cotton ............................................................28 Evaluating Pressure Compensating Subsurface Drip Irrigation for No-Till Row Crop Production on Rolling, Irregular Terrain......................................................................................................................................................29 FERTILITY Cotton Soil Fertility on Alabama Black Belt Soils ...........................................................................................................................31 Alternative Nitrogen Sources for Cotton ..........................................................................................................................................34 INSECT MANAGEMENT Effectiveness of Different Insecticides in Controlling Spider Mites and Aphids Infesting Cotton ..................................................35 Stink Bug Residual Control with Varying Classes of Chemistry......................................................................................................36 Stink Bug Threshold Verifi cation Trial (Late Planting Date) ...........................................................................................................37 Stink Bug Threshold Verifi cation Trial (Normal Planting Date) ......................................................................................................38 Systems Technology Trial, Prattville, Alabama ................................................................................................................................39 Systems Technology Trial, WREC, Headland, Alabama ..................................................................................................................40 WEED MANAGEMENT Evaluation of Herbicides for Palmer Amaranth Control in Cotton, Headland, Alabama 2008 ........................................................41 Residual Infl uence of Primary Tillage on Weed Control and Cotton Yield ......................................................................................42 Early Season Pigweed Control in Conservation Tillage Cotton .......................................................................................................43 DISEASE MANAGEMENT Evaluation of Seed Treatment Combinations with Seed Quality for Seedling Disease Management in Cotton in North Alabama, 2008 ............................................................................................................................................................45 Effi cacy of Experimental Compounds on the Fusarium Wilt Complex in Central Alabama, 2008 .................................................46 Effi cacy of Experimental Compounds on Early Season Cotton Diseases in North Alabama, 2008 ................................................48 Effi cacy of Combination Seed Treatments on Early Season Cotton Diseases in North Alabama, 2008 ..........................................51 Evaluation of the Experimental Compound V-10116 on Early Season Cotton Diseases in North Alabama, 2008 .........................52 CONTENTS, CONTINUED DISEASE MANAGEMENT, CONTINUED Evaluation of the Experimental Compound V-10190 on Early Season Cotton Diseases in North Alabama, 2008 .........................54 Evaluation of the Experimental Compound V-10208 on Early Season Cotton Diseases in North Alabama, 2008 .........................55 Evaluation of Cotton Seedling Disease Management in North Alabama, 2008 ...............................................................................56 NEMATODE MANAGEMENT Performance of Selected Cotton Varieties against the Root-Knot Nematode in Central Alabama, 2008 .........................................57 On-Farm Field Trials to Test the Effectiveness of Seed Nematacides for Managing Reniform and Root-Knot Nematodes on Cotton in Alabama ....................................................................................................................58 Cotton Response to Nemout® For Reniform Nematode Management in South Alabama, 2008 ....................................................59 Evaluation of Aeris Seed Treatment for Reniform Nematode Management in Cotton in North Alabama, 2008 ............................60 Evaluation of Experimental Seed Treatment Combinations for Reniform Nematode Management in Cotton in North Alabama, 2008 ............................................................................................................................................61 Evaluation of Experimental Nematicide Seed Treatments for Reniform Nematode Management in Cotton in North Alabama, 2008 ............................................................................................................................................63 Evaluation of Starter Fertilizer as a Means for Reniform Nematode Control in South Alabama, 2008 ..........................................65 Evaluation of Starter Fertilizer as a Means for Reniform Nematode Control in North Alabama, 2008 ..........................................66 Evaluation of Aeris Seed Treatment and Granular Nematicides for Reniform Nematode Management in South Alabama, 2008 ............................................................................................................................................................67 Evaluation of Experimental Biological Nematicide Seed Treatments for Reniform Nematode Management in Cotton in South Alabama,
Load more

Recommended publications
  • Chapter 9: Historic Preservation
    CHAPTER 9: HISTORIC PRESERVATION 9.1 Auburn Historic Preservation Commission he City of Auburn has a rich and diverse history. Organized efforts to preserve locally significant historic and cultural resources allow the City to recognize and protect its past, while T simultaneously planning for future development and growth. Preservation planning, or a lack thereof, can have a significant impact not only on aesthetic appearance, but on the unique sense of place created by a community. The Auburn Historic Preservation Commission (AHPC), the City’s governing body concerning issues of preservation, was created on March 2, 1999 with the passage of Ordinance 1818 by City Council. The Commission is comprised of seven members, and is intended to meet several essential needs. For the community, it assures that Auburn’s historic resources are maintained in a manner appropriate to the City’s heritage. For property owners, residents and contractors, it provides primary guidance in the planning and design of projects that are sympathetic to the special character of the historic district; and that will, in turn, assure that property values are maintained and enhanced. 9.2 North College Historic District On June 21, 2005 the City Council passed Ordinance 2302, which gave the AHPC the task of recommending designation of historic districts and properties in the city. These recommendations are presented to the Council, which then reviews them for final action. The City’s first locally designated district, the North College Historic District, contains 37 parcels north of downtown Auburn and was officially designated by Ordinance 2377 on March 21, 2006. All of the properties in the North College Historic District lie within the boundaries of the Old Main and Church Street District, a National Register of His toric Places District designated in 1978.
    [Show full text]
  • Annual Report of Accomplishments and Results: Multistate Extension Activities and Integrated Activities
    ANNUAL REPORT OF ACCOMPLISHMENTS AND RESULTS THE COMPREHENSIVE ALABAMA COOPERATIVE EXTENSION SYSTEM Alabama A&M University Auburn University Tuskegee University FISCAL YEAR 2002 TABLE OF CONTENTS PART ONE: ALABAMA A&M UNIVERSITY / AUBURN UNIVERSITY CERTIFICATION……………………………………………………….…………..PAGE 03 PREFACE……………………………………………………………………..........PAGE 04 INTRODUCTION………..................................................................................PAGE 05 Planning and Reporting Refinements……………………………….…...PAGE 06 NATIONAL GOALS: PROGRAM ACCOMPLISHMENTS………..………….…PAGE 07 Goal One…………………………………………………………………….PAGE 07 Goal Two…………………………………………………………………….PAGE 47 Goal Three………………………………………………………………..…PAGE 50 Goal Four........................................................................................…...PAGE 67 Goal Five…………………………………………………………………..…PAGE 90 ALLOCATION OF FISCAL AND HUMAN RESOURCES…………………….…PAGE 152 STAKEHOLDER INPUT…………………………………………………………….PAGE 153 PROGRAM REVIEW PROCESS…………………………………………………..PAGE 155 INTEGRATED RESEARCH & EXTENSION AND MULTISTATE ACTIVITIES………………………………………………………….PAGE 157 PART TWO: TUSKEGEE UNIVERSITY INTRODUCTION……………………………………………………………..……...PAGE 168 PROGRAM ACCOMPLISHMENTS, RESULTS, AND IMPACTS…..………….PAGE 170 Goal One………………………………………………………………….….PAGE 170 Goal Two……………………………………………………………………..PAGE 176 Goal Three………………………………………………………………...…PAGE 183 Goal Four........................................................................................…...PAGE 188 Goal Five…………………………………………………………………..…PAGE 191 ALLOCATION OF FISCAL
    [Show full text]
  • December 2015
    AA LL AA BB AA MM AA FarmersFarmers andand ConsumersConsumers BulletinBulletin Volume 63 No. 12 December 2015 McMillan’s 2015 AlAbAmA Century & Message HeritAge FArms AnnounCed Since the Commissioner Century and Heritage Farm John McMillan program began in 1976, the Supporting Gulf Seafood Department In early November, I of Agriculture expressed by appreciation to & Industries the Alabama Congressional has recognized delegation for their tireless almost 600 farms efforts on the passage of in Alabama. H.R. 774. The Illegal, This year 16 farms qualified Historical Commission If you feel your family farm Unreported, Unregulated for the program. Each farm Executive Director and Fishing Enforcement Act of qualifies for this program, be 2015 strengthens maritime has been in operation as a the Governor, officially sure to check the Alabama law enforcement’s ability to family farm for at least 100 designating their farm as an Farmers and Consumers stop foreign illegal fishing. years and reflects interesting Alabama Century and/or Bulletin next summer for It also implements the Port and important historical and Heritage Farm. Each family an announcement that States Measures Agreement agricultural qualities. These also receives an exterior farm applications are available for that denies port entry to farms demonstrate a durability sign to display at their farm the 2016 Century and Heritage foreign vessels engaged in Some Gulf shrimp go through the and love of the land that is gate. illegal fishing and protects the Farm program. Alabama Seafood Tissue Testing the heritage of the State of seafood industry by prohibiting Program, a long-term sampling The farms that received Alabama.
    [Show full text]
  • Auburnuniversity Crops
    Auburn University Crops: Soybean Research Report 2016 Research Report No. 43 Alabama Agricultural Experiment Station, 2017 Paul Patterson, Director Auburn University Auburn, AL In cooperation with the Alabama Cooperative Extension System (Alabama A&M University and Auburn University) Editors K. S. Lawrence Professor Entomology & Plant Pathology Auburn University, AL D. Delaney Extension Specialist Crop, Soil and Environmental Sciences Auburn University, AL Authors Abbreviations: ACES, Alabama Cooperative Extension System; AAES, Alabama Agricultural Experiment Station; AFNR, Agriculture, Forestry, and Natural Resources. K. Balkcom B. Dillard Research Agronomist Regional Extension Agent I National Soil Dynamics Lab Geneva County Extension Center Auburn University, AL Geneva, AL C. Hicks D. Dodge Regional Extension Agent II Graduate Student EV Smith Research Center Entomology & Plant Pathology Shorter, AL Auburn University, AL J. Coleman J. Kelton Assistant Professor Regional Extension Agent I Entomology & Plant Pathology ACES-AFNR-Field Auburn Univeristy, AL Headland, AL K. Conner Y. Feng Extension Specialist Professor Plant Pathology Crop, Soil and Environmental Sciences Auburn University, AL Auburn University, AL J. A. Tredaway B. Guertal Extension Specialist /Assistant Professor Professor Crop, Soil and Environmental Sciences Crop, Soil & Environmental Sciences Auburn University, AL Auburn University, AL D. Delaney M. Hall Extension Specialist Extension Specialist Crop, Soil and Environmental Sciences Alabama Cooperative Extension System Auburn University, AL Auburn, AL M. Delaney J. Howe Entomology & Plant Pathology Associate Professor (retired) Auburn University, AL Crop, Soil and Environmental Sciences Auburn University, AL 1 A. Jacobson J. Murphy Assistant Professor Professor Entomology & Plant Pathology Entomology & Plant Pathology Auburn University, AL Auburn University, AL T. Knappenberger B. Ortiz Assistant Professor Ext.
    [Show full text]
  • Genomics of Energy & Environment Meeting
    THE 11TH ANNUAL DOE Joint Genome Institute Genomics of Energy & Environment Meeting March 21-24, 2016 • Walnut Creek Marriott • Walnut Creek, California User Meeting Abstracts All information current as of March 15, 2016 JGI Contact: Denise Yadon DOE Joint Genome Institute [email protected] The Joint Genome Institute is a user facility of the Department of Energy Office of Science DOE Joint Genome Institute: www.jgi.doe.gov DOE Office of Science: science.energy.gov THE 11TH ANNUAL DOE Joint Genome Institute Genomics of Energy & Environment Meeting March 21-24, 2016 • Walnut Creek Marriott • Walnut Creek, California User Meeting Abstracts Sponsored By U.S. Department of Energy Office of Science Table of Contents Speaker Presentations .....................................................................................................1 Poster Presentations ......................................................................................................10 Index ..............................................................................................................125 Attendees ..............................................................................................................135 Speaker Presentations Speaker Presentations Abstracts alphabetical by speaker The Nature of Scientific Publishing Bahcall, Orli* ([email protected]) Nature. Tara Oceans: Eco-Systems Biology at Planetary Scale Bowler, Chris* ([email protected]); Tara Oceans Consortium Ecology and Evolutionary Biology Section, Institut de Biologie de l’Ecole
    [Show full text]
  • Long-Term Field Experiments Around the World
    Long-term Field Experiments Around the World Year established: 1843 Soil: Aquic Paleudalfs (Stagnogleyic paleo-argillic brown earth, silty clay loam) Location: Hertfordshire, UK Annual rainfall: 708 mm Name: Broadbalk Experiment Elevation: 167 m N 51°48’35” The Broadbalk Experiment at Rothamsted Research in Hertfordshire, UK, is the oldest, W 0°22’24” continuously running agricultural experiment in the world. It had its first winter-wheat crop sown in autumn 1843, and this crop has been sown and harvested on all, or part, of Current contact: Dr. Andrew Macdonald, Rothamsted Research Station, UK (andy. the field every year since then. The experiment tests the effects of various combinations [email protected]) and Dr. Paul Poulton ([email protected]). of inorganic fertilizer (supplying the elements N, P, K, Na, and Mg) and farmyard manure on the yield of wheat: a control strip has received no fertilizer or manure since 1843. Year established: 1876 Soil: Flanagan silt loam (fine, smectitic, mesic Aquic Argiudolls) Location: Urbana-Champaign, Illinois, USA Annual rainfall: 1009 mm Name: Morrow Plots Elevation: 229 m N 40°6’16.44” The Morrow Plots, located in the heart of the Urbana-Champaign campus of the W 88°13’33.96” University of Illinois, are the oldest continuous agricultural research fields in the United States. Established in 1876, they are predated only by the Rothamsted Field Current contact: Dr. Robert Dunker, Agronomist and Superintendent, Crop Sciences in England, which was started in 1843. The trials were originally started by Dr. Manley Research and Education Center, University of Illinois ([email protected]) Miles, Professor of Agriculture, University of Illinois.
    [Show full text]
  • Feed the Future Soil Fertility Technology (SFT)
    Feed the Future Soil Fertility Technology (SFT) Adoption, Policy Reform and Knowledge Management Project Semi-Annual Performance Report April 1, 2019 – September 30, 2019 Cooperative Agreement No. AID-BFS-IO-15-00001 Contents Progress Toward Cooperative Agreement Award Objectives...................................................1 1. Workstream 1 – Developing and Validating Technologies, Approaches, and Practices ....................................................................................................................................4 Technologies Developed, Refined, and Adapted for Improving Nitrogen Use Efficiency ........................................................................................................................4 1.1.1 Development and Evaluation of Enhanced Efficiency N Fertilizers............... 5 1.1.2 Scaling Fertilizer Deep Placement Technology through Mechanization ............................................................................................... 18 1.1.3 Climate Resilience and Mitigating GHG Emissions ..................................... 21 1.1.4 CO2 Mitigation Role of Enhanced Efficiency Fertilizers and Practices ........ 23 Activated Phosphate Rock .............................................................................................23 1.2.1 Complete and Analyze Ongoing Field Trials ................................................ 24 1.2.2 Activated PR Demonstrations ....................................................................... 27 Balanced Crop Nutrition (Cross-Cutting
    [Show full text]
  • Long-Term Field Experiments Around the World
    Long-term Field Experiments Around the World 1 Long-term Field Experiments Around the World 1 2 3 4 5 6 7 8 9 10 11 12 Photographs are provided by each respective university/experiment station for authorized use. Year established: 1843 Soil: Aquic Paleudalfs (Stagnogleyic paleo-argillic brown earth, silty clay loam) Location: Hertfordshire, UK Annual rainfall: 708 mm Name: Broadbalk Experiment Elevation: 167 m N 51°48’35” The Broadbalk Experiment at Rothamsted Research in Hertfordshire, UK, is the oldest, W 0°22’24” continuously running agricultural experiment in the world. It had its first winter-wheat crop sown in autumn 1843, and this crop has been sown and harvested on all, or part, of Current contact: Dr. Andrew Macdonald, Rothamsted Research Station, UK (andy. the field every year since then. The experiment tests the effects of various combinations [email protected]) and Dr. Paul Poulton ([email protected]). of inorganic fertilizer (supplying the elements N, P, K, Na, and Mg) and farmyard manure on the yield of wheat: a control strip has received no fertilizer or manure since 1843. 1 Year established: 1876 Soil: Flanagan silt loam (fine, smectitic, mesic Aquic Argiudolls) Location: Urbana-Champaign, Illinois, USA Annual rainfall: 1009 mm Name: Morrow Plots Elevation: 229 m N 40°6’16.44” The Morrow Plots, located in the heart of the Urbana-Champaign campus of the W 88°13’33.96” University of Illinois, are the oldest continuous agricultural research fields in the United States. Established in 1876, they are predated only by the Rothamsted Field Current contact: Dr.
    [Show full text]
  • Hfn— - — ______/Signature of Certifying Official Date
    NPS Form 10-900 0MB No. 1024-0018 (Rev. 10-90) United States Department of the Interior -6 National Park Service NATIONAL REGISTER OF HISTORIC PLACES REGISTRATION FORM 1. Name of Property historic name Cullars Rotation other names/site number Alvis Field 2. Location street & number Woodfield Drive, approx. 200 feet east of US Hwv 29 . not for publication N/A city or town Auburn_________________________ vicinity N/A state Alabama_______ code AL county Lee___ code 081 zip code 36830 3. State/Federal Agency Certification As the designated authority under the National Historic Preservation Act of 1966, as amended, I hereby certify that this X nomination __ request for determination of eligibility meets the documentation standards for registering properties in the National Register of Historic Places and meets the procedural and professional requirements set forth in 36 CFR Part 60. In y opinion, the property X meets __ does not meet the National Register Criteria. I recommend that this property be onsidered significant _ nationally X statewide _ locally. ( _ See continuation sheet for additional comments.) hfn —- —_______ /Signature of certifying official Date Alabama Historical Commission (State Historic Preservation Office) _ State or Federal agency and bureau In my opinion, the property __ meets does not meet the National Register criteria. ( _ See continuation sheet for additional comments.) Signature of commenting or other official Date State or Federal agency and bureau 4. National Park Service Certification hereby certify that this property is: Signature of the Keener A An Date of Action [/f entered in the National Register [ ] See continuation sheet. [ ] determined eligible for the National Register [ ]See continuation sheet.
    [Show full text]
  • Auburnuniversity Crops
    Auburn University Crops: Soybean Research Report 2013 & 2014 Research Report No. 45 Alabama Agricultural Experiment Station, 2015 Art Appel, Director Auburn University Auburn, AL 1 Authors Y. Feng Professor D. Bailey Crop, Soil and Environmental Sciences Graduate student Auburn University, AL Entomology and Plant Pathology Auburn University, AL J. P. Fulton Associate Professor K. Balkcom Biosystems Engineering National Soil Dynamics Lab Auburn University, AL Auburn University, AL W. Griffith A. Brooke County Extension Coordinator Technician I Fayette County Biosystems Engineering Auburn University, AL M. Hall Extension Specialist C. H. Burmester Renewable Fuels, Agronomist Alabama Cooperative Extension System Tennessee Valley Research and Auburn, AL Extension Center Belle Mina, AL J. Howe Associate Professor K. Conner Crop, Soil and Environmental Sciences Extension Specialist Auburn University, AL Plant Pathology Auburn University, AL C. Hicks D. Delaney Regional Extension Agent, I Extension Specialist Alabama Cooperative Extension System Crop, Soil and Environmental Sciences Auburn, AL Auburn University, AL G. Huluka M. Delaney Associate Professor Entomology & Plant Pathology Crop, Soil and Environmental Sciences Auburn University, AL Auburn University, AL D. Derrick K.S. Lawrence Regional Extension Agent III Professor Cherokee County Entomology and Plant Pathology Centre, AL Auburn University, AL C. Dillard P.L. Mask Extension Specialist Asst. Director Agriculture, Forestry and Cooperative Extension System National Resources Auburn University, AL Assistant Dean for Extension Auburn University, AL P. Donald Adjunct Professor Entomology and Plant Pathology Auburn University, AL 2 C.C. Mitchell M. Runge Extension Specialist Professor Extension Program Associate Crop, Soil and Environmental Sciences Agricultural Economics & Rural Sociology Auburn University, AL Auburn University, AL C.D.
    [Show full text]
  • Cullars Rotation: the South’S Oldest Continuous Soil Fertility Experiment by Charles C
    ALABAMA Cullars Rotation: The South’s Oldest Continuous Soil Fertility Experiment By Charles C. Mitchell, Dennis Delaney, and Kipling S. Balkcom Long-term fertility research with major crop rotations provides valuable nutrient management information in addressing sustainable production. The South’s oldest fertility experiment is located in Auburn, Alabama. It continues to illustrate the ben- efits of balanced plant nutrition and fertilizing for the needs of the crop rotation. labama’s “Cullars Rotation” experiment (established in 1911) A was placed on the National Regis- ter of Historical Places in 2003 as the old- est continuous soil fertility experiment in the South. Along with its nearby prede- cessor on the National Register, “The Old Rotation,” which started in 1896, these experiments contain the oldest cotton re- search plots in the world. Both are located on the campus of Auburn University in east-central Alabama. Treatments on the Cullars Rotation View of experiment looking toward the east with plots dramatically demonstrate the long-term A, B, and C on the right. effects of fertilization and the lack of spe- cific nutrients on non-irrigated crop yields on this site led to the discovery of K defi- over a 95-year period. The Cullars Rota- ciency in cotton, which had been referred tion is one of the few sites where controlled to earlier as “cotton rust” (Atkinson, 1891, nutrient deficiencies can be observed on 1892). Today, the experiment is a 3-year five different crops during the course of a rotation of: 1) cotton followed by crimson year (cotton, crimson clover, corn, wheat, clover, 2) corn harvested for grain and fol- and soybean).
    [Show full text]
  • Response of Diazotrophic Microbial Community to Nitrogen Input and Glyphosate Application in Soils Cropped to Soybean
    Response of diazotrophic microbial community to nitrogen input and glyphosate application in soils cropped to soybean by Lu Fan A dissertation submitted to the Graduate Faculty of Auburn University in partial fulfillment of the requirements for the Degree of Doctor of Philosophy Auburn, Alabama December 14, 2013 Keywords: diazotrophic microbial community, glyphosate, ARA, DGGE, qPCR Copyright 2013 by Lu Fan Approved by Yucheng Feng, Chair, Professor, Dept. of Crop, Soil & Environmental Sciences Mark Liles, Associate Professor, Dept. of Biological Sciences Andrew Price, Affiliate Associate Professor, Dept. of Crop, Soil & Environmental Sciences Dongye Zhao, Elton Z. and Lois G. Huff Professor, Dept. of Civil & Environmental Engineering Abstract Diazotrophic bacteria play a critical role in biological N fixation by converting atmospheric nitrogen to ammonium that can be used by plants. About 80% of biological N fixation can be attributed to diazotrophs in symbiosis with legumes. Soybean (Glycine max L. Merr.), a leguminous food crop, is the second largest crop (by value) in the U.S., with 93% of the planted soybean being genetically modified to tolerate the herbicide glyphosate. Inclusion of leguminous crops in crop production systems reduces the need for nitrogenous fertilizer and thus reduces cost, possible N pollution and fossil fuel consumption. Many factors affect symbiotic N fixation. This work examined the effects of two important factors—N input and glyphosate application—on the soil diazotrophic community and N fixation associated with soybean. The first study assessed the response of the diazotrophic community to N input in a century-old crop rotation experiment, the Cullars Rotation, located in Auburn, Alabama.
    [Show full text]