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Articles 121 - 150 of 218

Full-Text Articles in Agronomy and Crop Sciences

Genomic And Physiological Approaches To Improve Drought Tolerance In Soybean, Avjinder Kaler Aug 2017

Genomic And Physiological Approaches To Improve Drought Tolerance In Soybean, Avjinder Kaler

Graduate Theses and Dissertations

Drought stress is a major global constraint for crop production, and improving crop tolerance to drought is of critical importance. Direct selection of drought tolerance among genotypes for yield is limited because of low heritability, polygenic control, epistasis effects, and genotype by environment interactions. Crop physiology can play a major role for improving drought tolerance through the identification of traits associated with drought tolerance that can be used as indirect selection criteria in a breeding program. Carbon isotope ratio (δ13C, associated with water use efficiency), oxygen isotope ratio (δ18O, associated with transpiration), canopy temperature (CT), canopy wilting, and canopy coverage …


Modeling Gross Primary Production Of Midwest Maize And Soybean Croplands With Satellite And Gridded Weather Data, Gunnar Malek-Madani Apr 2017

Modeling Gross Primary Production Of Midwest Maize And Soybean Croplands With Satellite And Gridded Weather Data, Gunnar Malek-Madani

Department of Geography: Dissertations, Theses, and Student Research

The gross primary production (GPP) metric is useful in determining trends in the terrestrial carbon cycle. Models that determine GPP utilizing the light use efficiency (LUE) approach in conjunction with biophysical parameters that account for local weather conditions and crop specific factors are beneficial in that they combine the accuracy of the biophysical model with the versatility of the LUE model. One such model developed using in situ data was adapted to operate with remote sensing derived leaf area index (LAI) data and gridded weather datasets. The model, known as the Light Use Efficiency GPP Model (EGM), uses a four …


Emergence, Competition, And Management Of Glyphosate-Resistant Common Ragweed (Ambrosia Artemisiifolia L.) In Nebraska Soybean, Ethann R. Barnes Apr 2017

Emergence, Competition, And Management Of Glyphosate-Resistant Common Ragweed (Ambrosia Artemisiifolia L.) In Nebraska Soybean, Ethann R. Barnes

Department of Agronomy and Horticulture: Dissertations, Theses, and Student Research

Common ragweed (Ambrosia artemisiifolia L.) is a competitive annual broadleaf weed in soybean (Glycine max) production fields throughout North America. The recent confirmation of glyphosate-resistant common ragweed in Nebraska justified the need to assess the emergence pattern and competitive ability of common ragweed in soybean and to evaluate alternative herbicide programs for effective management. The objectives of this research were to: 1) evaluate the effect of tillage and develop a predictive model for the emergence pattern of common ragweed in Nebraska; 2) model the competitive interaction between soybean and common ragweed as influenced by density and irrigation …


Arkansas Soybean Research Studies 2015, Jeremy Ross Feb 2017

Arkansas Soybean Research Studies 2015, Jeremy Ross

Arkansas Agricultural Experiment Station Research Series

Arkansas is the leading soybean-producing state in the mid-southern United States. Arkansas ranked 10th in soybean production in 2015 when compared to the other soybean-producing states in the U.S. The state represents 4.0% of the total U.S. soybean production and 3.7% of the total acres planted to soybean in 2015. The 2015 state soybean average was 49 bushels per acres, 0.5 bushel per acres less than the state record soybean yield set in 2014 (Table 1). The top five soybean-producing counties in 2015 were Mississippi, Desha, Poinsett, Phillips, and Arkansas Counties. These five counties accounted for 35% of soybean production …


Phytophthora Sojae Infecting Soybean: Pathotype Diversity, New Sources Of Resistance And Interaction With The Soybean Cyst Nematode, Rawnaq Nazneen Chowdhury Jan 2017

Phytophthora Sojae Infecting Soybean: Pathotype Diversity, New Sources Of Resistance And Interaction With The Soybean Cyst Nematode, Rawnaq Nazneen Chowdhury

Electronic Theses and Dissertations

Phytophthora root and stem rot, caused by Phytophthora sojae Kaufmann and Gerdemann, is an important disease of soybean (Glycine max L.) in South Dakota. To gain a better understanding of the importance of P. sojae in South Dakota, specifically pathotype diversity, identification of new resistance sources and the interaction with the soybean cyst nematode (Heterodera glycines Ichinohe, SCN), this research was undertaken with the following objectives - 1) to characterize the pathotype diversity of P. sojae causing Phytophthora root and stem rot on soybean in commercial fields in South Dakota; 2) to compare inoculation methods to evaluate for …


Gene Silencing Of Argonaute5 Negatively Affects The Establishment Of The Legume-Rhizobia Symbiosis, Maria Del Rocio Reyero-Saavedra, Zhenzhen Qiao, Maria Del Socorro Sanchez-Correa, M. Enrique Diaz-Pineda, Jose L. Reyes, Alejandra A. Covarrubias, Marc Libault, Oswaldo Valdes-Lopez Jan 2017

Gene Silencing Of Argonaute5 Negatively Affects The Establishment Of The Legume-Rhizobia Symbiosis, Maria Del Rocio Reyero-Saavedra, Zhenzhen Qiao, Maria Del Socorro Sanchez-Correa, M. Enrique Diaz-Pineda, Jose L. Reyes, Alejandra A. Covarrubias, Marc Libault, Oswaldo Valdes-Lopez

Department of Agronomy and Horticulture: Faculty Publications

The establishment of the symbiosis between legumes and nitrogen-fixing rhizobia is finely regulated at the transcriptional, posttranscriptional and posttranslational levels. Argonaute5 (AGO5), a protein involved in RNA silencing, can bind both viral RNAs and microRNAs to control plant-microbe interactions and plant physiology. For instance, AGO5 regulates the systemic resistance of Arabidopsis against Potato Virus X as well as the pigmentation of soybean (Glycine max) seeds. Here, we show that AGO5 is also playing a central role in legume nodulation based on its preferential expression in common bean (Phaseolus vulgaris) and soybean roots and nodules. We also …


Dissecting Salt Tolerance In Soybean By Profiling Differential Physiological Responses Under Salt Stress, Jade Amber Newsome Dec 2016

Dissecting Salt Tolerance In Soybean By Profiling Differential Physiological Responses Under Salt Stress, Jade Amber Newsome

Graduate Theses and Dissertations

Saline soils are common worldwide and limit the yield potential of many crops. Plants respond in a variety of ways to the stress imposed by saline soils. Plants under salt stress must first sense their surroundings and transmit a signal alerting the rest of the plant to the saline conditions. Salt tolerance in soybeans is typically defined by exclusion of chloride ions from foliar tissues. Though differences in ion uptake among soybean genotypes is well documented, the key mechanisms employed by tolerant cultivars to cope with salt stress on the whole-plant level are still largely unknown. Objectives of the current …


Arkansas Soybean Performance Tests 2016, R. D. Bond, J. A. Still, D. G. Dombek Dec 2016

Arkansas Soybean Performance Tests 2016, R. D. Bond, J. A. Still, D. G. Dombek

Arkansas Agricultural Experiment Station Research Series

Soybean variety and strain performance tests are conducted each year in Arkansas by the University of Arkansas System Division of Agriculture’s Arkansas Crop Variety Improvement Program. The tests provide information to companies developing varieties and/or marketing seed within the State, and aid the Arkansas Cooperative Extension Service in formulating variety recommendations for soybean producers.


Quantitative Trait Loci Mapping, Genome-Wide Association Analysis, And Gene Expression Of Salt Tolerance In Soybean, Ailan Zeng Dec 2016

Quantitative Trait Loci Mapping, Genome-Wide Association Analysis, And Gene Expression Of Salt Tolerance In Soybean, Ailan Zeng

Graduate Theses and Dissertations

Salt stress is a common abiotic stress causing yield reduction in soybean. There are differential responses, namely tolerance (excluder) and intolerance (includer), among soybean germplasm. However, the genetic and physiological mechanism for salt tolerance is not clear. Identification of novel QTL for salt tolerance and genes that are differentially expressed under salt stress would help elucidate the salt tolerance mechanism and facilitate the development of salt tolerant cultivars through marker assisted selection (MAS). The objectives of this study were to identify new QTL or genes responsible for salt tolerance using three approaches: QTL mapping, association analysis, and RNA sequencing (RNA-seq). …


Selection Of Drought-Tolerant Soybean Lines Using A Field Screening Method And Identification Of Qtls For Slow Wilting And Nitrogen Fixation Associated With Drought-Tolerance, Mirta Beatriz Dalzotto Dec 2016

Selection Of Drought-Tolerant Soybean Lines Using A Field Screening Method And Identification Of Qtls For Slow Wilting And Nitrogen Fixation Associated With Drought-Tolerance, Mirta Beatriz Dalzotto

Graduate Theses and Dissertations

Drought causes significant yield reductions in soybean. The development of drought-tolerant cultivars is an effective alternative to overcome this abiotic stress. Slow wilting, prolonged nitrogen fixation, and minimal yield reduction under water stress play an important role in evaluating breeding materials. Despite advances in knowledge about plant responses to drought conditions, there is little information on effective methodologies for phenotype screening in the field, and some QTLs have been identified for drought tolerance. Field screenings under drought and irrigated conditions are necessary to detect drought tolerant lines. In addition, QTLs and molecular makers associated with drought tolerance traits will greatly …


Soil And Plant Property Differences Among High-Yield Soybean Areas In Arkansas, Taylor Cass Adams Dec 2016

Soil And Plant Property Differences Among High-Yield Soybean Areas In Arkansas, Taylor Cass Adams

Graduate Theses and Dissertations

Continued achievement of soybean [Glycine max (L.) Merr.] yields greater than 6719 kg ha-1 (100 bu ac-1) will depend on decreasing the yield gap, which is contingent on gathering more information regarding the soil physical, chemical, and microbiological environment and the main plant factors contributing to high-yield soybean. Therefore, understanding the main factor differences between high- and average-yield areas may provide insight for making management decisions to increase yields. The objectives of this study were i) to evaluate the effects of region and soil depth on soil property differences between high- and average-soybean-yielding areas, ii) to determine which soil properties …


Modeling Long-Term Corn Yield Response To Nitrogen Rate And Crop Rotation, Laila A. Puntel, John E. Sawyer, Daniel W. Barker, Ranae Dietzel, Hanna Poffenbarger, Michael J. Castellano, Kenneth J. Moore, Peter J. Thorburn, Sotirios V. Archontoulis Nov 2016

Modeling Long-Term Corn Yield Response To Nitrogen Rate And Crop Rotation, Laila A. Puntel, John E. Sawyer, Daniel W. Barker, Ranae Dietzel, Hanna Poffenbarger, Michael J. Castellano, Kenneth J. Moore, Peter J. Thorburn, Sotirios V. Archontoulis

Department of Agronomy and Horticulture: Faculty Publications

Improved prediction of optimal N fertilizer rates for corn (Zea mays L.) can reduce N losses and increase profits. We tested the ability of the Agricultural Production Systems sIMulator (APSIM) to simulate corn and soybean (Glycine max L.) yields, the economic optimum N rate (EONR) using a 16-year field-experiment dataset from central Iowa, USA that included two crop sequences (continuous corn and soybean-corn) and five N fertilizer rates (0, 67, 134, 201, and 268 kg N ha-1) applied to corn. Our objectives were to: (a) quantify model prediction accuracy before and after calibration, and report calibration steps; (b) …


Temperature Control Of Node Appearance And Initiation In Soybean, Fatima Amor M. Tenorio Aug 2016

Temperature Control Of Node Appearance And Initiation In Soybean, Fatima Amor M. Tenorio

Department of Agronomy and Horticulture: Dissertations, Theses, and Student Research

Soybean demand remains strong and continues to grow as a source of protein and oil for food and feed. Soybean production is expanding into cooler and warmer environments, thus, it becomes critical to expand the current knowledge about the influence of temperature on soybean. Temperature is the main environmental factor effecting node appearance rate (NAR) and node initiation rate (NIR), which are key parameters controlling soybean growth and development. This study aims to assess the response of NAR and NIR to temperature and investigate the coordination between these two processes under controlled and field conditions. Two greenhouse experiments with four …


High Throughput Phenotypic Evaluation Of Drought-Related Traits In Soybean, Hua Bai Aug 2016

High Throughput Phenotypic Evaluation Of Drought-Related Traits In Soybean, Hua Bai

Graduate Theses and Dissertations

Drought limits crop growth and yield in soybean. Rapid and effective methods of screening large numbers of soybean lines for drought tolerance are urgently needed. Two experiments were conducted to evaluate the effects of drought in soybean during reproductive stages. In the first experiment five genotypes from maturity groups 2 through 5 were tested under well-irrigated and drought conditions. Beginning at R5, leaf samples were taken for nitrogen concentration analysis. Pictures were taken across the top of each plot to determine the intensity of greenness using the Dark Green Color Index (DGCI). Aerial photographs were also taken to determine aerial …


Distribution Of Genomic Variation In The Usda Soybean Germplasm Collection And Relationship With Phenotypic Variation, Nonoy Batiller Bandillo Jul 2016

Distribution Of Genomic Variation In The Usda Soybean Germplasm Collection And Relationship With Phenotypic Variation, Nonoy Batiller Bandillo

Department of Agronomy and Horticulture: Dissertations, Theses, and Student Research

The USDA Soybean Germplasm Collection harbors a large stock of genetic diversity with potential to accelerate soybean cultivar development. The extent and nature of favorable alleles contained in the collection are not well known nor is the distribution of genetic variation and how it relates to phenotypic variation. The genotyping of the entire USDA Soybean Germplasm Collection marked the beginning of a systematic exploration of genetic diversity for genetic research and breeding. In this research, we conducted the first comprehensive analysis of population structure on the collection of ~14,400 soybean accessions [Glycine max (L.) Merr. and G. soja Siebold …


Arkansas Soybean Research Studies 2014, Jeremy Ross May 2016

Arkansas Soybean Research Studies 2014, Jeremy Ross

Arkansas Agricultural Experiment Station Research Series

No abstract provided.


On-Farm Demonstration Of Computerized Hole Selection Programs In Arkansas Commercial Soybean And Cotton Fields And Evaluation Of Polyacrylamide In Plot-Scale Furrow Irrigated Cotton, Austin Lorenzo Lewis Apr 2016

On-Farm Demonstration Of Computerized Hole Selection Programs In Arkansas Commercial Soybean And Cotton Fields And Evaluation Of Polyacrylamide In Plot-Scale Furrow Irrigated Cotton, Austin Lorenzo Lewis

Student Theses and Dissertations

Groundwater depletion is a rising concern in the Midsouth region of the U.S. Many crops depend on the use of groundwater in order to meet water demands and potentially reach higher yields. Products and practices have been developed to conserve both groundwater and surface water by using easily collected field data to improve irrigation advance uniformity, infiltration, irrigation runoff water quality, and reduce irrigation runoff. A field demonstration was initiated to determine the value of incorporating the computerized hole selection program, Pipe Planner, into two commercial cotton fields and two commercial soybean fields. The cotton fields were located in Judd …


Simulating Long-Term Impacts Of Cover Crops And Climate Change On Crop Production And Environmental Outcomes In The Midwestern United States, Andrea D. Basche, Sotririos V. Archontoulis, Thomas C. Kaspar, Dan B. Jaynes, Timothy B. Parkin, Fernando E. Miguez Jan 2016

Simulating Long-Term Impacts Of Cover Crops And Climate Change On Crop Production And Environmental Outcomes In The Midwestern United States, Andrea D. Basche, Sotririos V. Archontoulis, Thomas C. Kaspar, Dan B. Jaynes, Timothy B. Parkin, Fernando E. Miguez

Department of Agronomy and Horticulture: Faculty Publications

It is critical to evaluate conservation practices that protect soil and water resources from climate change in the Midwestern United States, a region that produces one-quarter of the world’s soybeans and one-third of the world’s maize. An over-winter cover crop in a maize–soybean rotation offers multiple potential benefits that can reduce the impacts of higher temperatures and more variable rainfall; some of the anticipated changes for the Midwest. In this experiment we used the Agricultural Production Systems sIMulator (APSIM) to understand how winter rye cover crops impact crop production and environmental outcomes, given future climate change. We first tested APSIM …


Prospects Of Genomic Prediction In The Usda Soybean Germplasm Collection: Historical Data Creates Robust Models For Enhancing Selection Of Accessions, Diego Jarquin, James Specht, Aaron Lorenz Jan 2016

Prospects Of Genomic Prediction In The Usda Soybean Germplasm Collection: Historical Data Creates Robust Models For Enhancing Selection Of Accessions, Diego Jarquin, James Specht, Aaron Lorenz

Department of Agronomy and Horticulture: Faculty Publications

The identification and mobilization of useful genetic variation from germplasm banks for use in breeding programs is critical for future genetic gain and protection against crop pests. Plummeting costs of next-generation sequencing and genotyping is revolutionizing the way in which researchers and breeders interface with plant germplasm collections. An example of this is the high density genotyping of the entire USDA Soybean Germplasm Collection. We assessed the usefulness of 50K SNP data collected on 18,480 domesticated soybean (G. max) accessions and vast historical phenotypic data for developing genomic prediction models for protein, oil, and yield. Resulting genomic prediction models explained …


Construction Of High Resolution Genetic Linkage Maps To Improve The Soybean Genome Sequence Assembly Glyma1.01, Qijian Song, Jerry Jenkins, Gaofeng Jia, David L. Hyten, Vince Pantalone, Scott A. Jackson, Jeremy Schmutz, Perry B. Cregan Jan 2016

Construction Of High Resolution Genetic Linkage Maps To Improve The Soybean Genome Sequence Assembly Glyma1.01, Qijian Song, Jerry Jenkins, Gaofeng Jia, David L. Hyten, Vince Pantalone, Scott A. Jackson, Jeremy Schmutz, Perry B. Cregan

Department of Agronomy and Horticulture: Faculty Publications

Background: A landmark in soybean research, Glyma1.01, the first whole genome sequence of variety Williams 82 (Glycine max L. Merr.) was completed in 2010 and is widely used. However, because the assembly was primarily built based on the linkage maps constructed with a limited number of markers and recombinant inbred lines (RILs), the assembled sequence, especially in some genomic regions with sparse numbers of anchoring markers, needs to be improved. Molecular markers are being used by researchers in the soybean community, however, with the updating of the Glyma1.01 build based on the high-resolution linkage maps resulting from this research, …


The Effects Of Meloidogyne Incognita And Heterodera Glycines On The Yield And Quality Of Edamame In Arkansas, Juliet Fultz Dec 2015

The Effects Of Meloidogyne Incognita And Heterodera Glycines On The Yield And Quality Of Edamame In Arkansas, Juliet Fultz

Graduate Theses and Dissertations

Edamame (Glycine max), also known as vegetable soybean, was introduced to the United States from Japan in 1890 and has been growing in popularity as a nutrient-rich, low-sugar snack in recent years. In 2012, the American Vegetable Soybean and Edamame, Inc. established the first domestic commercial processing plant in Mulberry, Arkansas and contracted local growers for production. Since the crop is harvested when seed are immature, management practices are different from those for traditional soybean. Plant-parasitic nematodes, particularly Meloidogyne incognita (southern root-knot) and Heterodera glycines (soybean cyst), are common in Arkansas and are pests of concern for edamame growers. Edamame …


Arkansas Soybean Performance Tests 2015, R. D. Bond, J. A. Still, D. G. Dombek Dec 2015

Arkansas Soybean Performance Tests 2015, R. D. Bond, J. A. Still, D. G. Dombek

Arkansas Agricultural Experiment Station Research Series

Soybean variety and strain performance tests are conducted each year in Arkansas by the University of Arkansas System Division of Agriculture’s Arkansas Crop Variety Improvement Program. The tests provide information to companies developing varieties and/or marketing seed within the State, and aid the Arkansas Cooperative Extension Service in formulating variety recommendations for soybean producers.


Defining The Potassium Nutritional Requirements And Distribution Among Plant Parts Of Representative Soybean Cultivars From Different Maturity Groups, Md. Rasel Parvej Dec 2015

Defining The Potassium Nutritional Requirements And Distribution Among Plant Parts Of Representative Soybean Cultivars From Different Maturity Groups, Md. Rasel Parvej

Graduate Theses and Dissertations

The potassium (K) requirement of soybean [Glycine max (L.) Merr.] was investigated to determine whether cultivar sensitivity to K deficiency was affected by growth habit (determinate or indeterminate) and how cultivars from each growth habit accumulate and distribute K among plant structures. We also diagnosed K deficiency across reproductive growth stages (R2-6) using trifoliolate leaf- and petiole-K concentrations and at harvest (R8) using seed-K concentration. Soybean responded similarly to K deficiency in terms of yield, selected yield components, and seed-K concentration, regardless of growth habit. The yield loss from K deficiency was greatest on the middle to upper nodes of …


Validation Of Soil-Test-Based Phosphorus And Potassium Fertilizer Recommendations For Rice And Soybean, Matthew Scott Fryer Dec 2015

Validation Of Soil-Test-Based Phosphorus And Potassium Fertilizer Recommendations For Rice And Soybean, Matthew Scott Fryer

Graduate Theses and Dissertations

The science of soil-testing for nutrient management and fertilizer recommendations is widely accepted among scientists and agronomists. Although this science is unsurpassed in predicting soil nutrient availability, soil-test interpretations are seldom validated. Major research objectives for irrigated soybean [Glycine max (L.) Merr.] and direct-seeded, delayed-flood rice (Oryza sativa L.) were to: i) validate the accuracy of Mehlich-3 soil-test P (STP) and K (STK) interpretations and ii) published critical tissue-P and -K interpretations in predicting the yield response to fertilizer at different significance levels (p≤0.05 to 0.25), iii) examine how seed nutrient concentrations are influenced by fertilization and crop response to …


Soybean Planting And Risk-Return Tradeoffs In The Mid-Southern United States, Weston Weeks Dec 2015

Soybean Planting And Risk-Return Tradeoffs In The Mid-Southern United States, Weston Weeks

Graduate Theses and Dissertations

This thesis is comprised of two studies on the effects of soybean (Glycine max (L.) Merr.) planting date (PD) and maturity group (MG) selection on producer expected returns. Having to replant soybean after early-season planting because of poor stand establishment is costly for producers. Replanting costs have increased in the last ten years as seed and other input costs for soybean have increased. Using five years of field trial results from two locations in Arkansas, the yield response to early and late season plant population density has been estimated to determine yield and future revenue potential for the purpose of …


Soybean Irrigation Initiation Timing Using Evapotranspiration And Soil Moisture Sensor Cues, Justin Chlapecka Nov 2015

Soybean Irrigation Initiation Timing Using Evapotranspiration And Soil Moisture Sensor Cues, Justin Chlapecka

Student Theses and Dissertations

Expanded use of irrigation management tools is needed to improve water use efficiency in eastern Arkansas soybean (Glycine max) production. Irrigation initiation timing was studied on a furrow irrigated, sandy loam commercial field in Mississippi County. A major objective was to develop, validate, and expand use of irrigation timing cues, incorporating local weather station data, atmometers, and soil moisture measurements. Four timing treatments were evaluated: early, recommended, late, and rainfed, and the crop and pest response to each. With above average rainfall in 2014 and 2015, results showed little variation of soybean yield. Yield monitor data indicated penalties only within …


Soybean Seed Quality And Vigor: Influencing Factors, Measurement, And Pathogen Characterization, Kimberly Ann Cochran Jul 2015

Soybean Seed Quality And Vigor: Influencing Factors, Measurement, And Pathogen Characterization, Kimberly Ann Cochran

Graduate Theses and Dissertations

High seed vigor (SV), or the ability of seed to germinate and grow in a stressful environment is important, as many field emergence conditions are stressful for germination. Soybean SV can be affected by cultivar, seed storage environment conditions, the growing environment during seed development, crop management practices such as foliar fungicide applications, pathogens, and other factors. To assess the effects of some of these factors on soybean, the objectives of this work were to determine 1. the effect of cultivar and foliar azoxystrobin application on soybean yield, germination, vigor, microflora, and their relationships under harvest delay conditions; 2. if …


Long-Term Effects Of Alternative Residue Management Practices On Near-Surface Soil Properties And Soybean Production In A Wheat-Soybean, Double-Crop System In Eastern Arkansas, Christopher Ryan Norman Jul 2015

Long-Term Effects Of Alternative Residue Management Practices On Near-Surface Soil Properties And Soybean Production In A Wheat-Soybean, Double-Crop System In Eastern Arkansas, Christopher Ryan Norman

Graduate Theses and Dissertations

Adoption of management practices that maintain or increase soil organic matter (SOM), which contains 58% carbon (C) on average, may help to mitigate climate change by sequestering atmospheric C. Therefore, the main objective of this study was to determine the long-term trends in SOM, soil C and nitrogen (N), bulk density, various soil chemical properties (i.e., pH, electrical conductivity [EC], and Mehlich-3-extractable nutrients) in the top 10 cm, and soybean yield as affected by residue burning (burning and non-burning), tillage (conventional and no-tillage), irrigation (irrigated and non-irrigated), and N-fertilization/residue level (high and low) in a wheat (Triticum aestivum L.)-soybean [Glycine …


Physiological And Nutritional Characterization Of High Yield Soybean, Ryan John Van Roekel May 2015

Physiological And Nutritional Characterization Of High Yield Soybean, Ryan John Van Roekel

Graduate Theses and Dissertations

Soybean [Glycine max (L.) Merr.] grain yields greater than three times the national average have been reported in yield contests. Characterization of soybean in a maximum yield environment is necessary to provide empirical data to support those yield claims and to provide an understanding of the physiological processes at that yield level. From 2011 to 2013, research characterized biomass and N accumulation rates, radiation use efficiency (RUE), leaf N dynamics, the rate of harvest index increase (dry matter allocation coefficient, DMAC), seedfill period (SFP), and grain yield components from Mr. Kip Cullers' contest fields and in small plots at the …


The Suitability Of Energy Beets For Double-Cropping With Soybeans In The Arkansas Delta, Tyler Caleb Meadors Apr 2015

The Suitability Of Energy Beets For Double-Cropping With Soybeans In The Arkansas Delta, Tyler Caleb Meadors

Student Theses and Dissertations

The climate of the midsouthern USA allows increased potential for crop productivity through the double-crop production system (DCPS), by way of more intensive land usage. Despite this potential, DCPS utilization has decreased in Arkansas over the past 10 years, due, in part, to delayed soybean planting. An alternative winter crop with earlier harvest timing than winter wheat could lessen this risk, yet still capitalize on the area's winter crop potential. The objective of this study was to determine the agronomic viability of an energy beet/soybean DCPS in Arkansas. A field study was conducted in Jonesboro, AR from September 2012 to …