Agronomy and Crop Sciences Commons^™

Comparison Of A T-Trellis And A Rotating Cross-Arm Trellis For Arkansas Blackberry Production, Erika Henderson

Graduate Theses and Dissertations

As blackberry production in the southeastern United States expands, the need for updated cultural practices, like alternative trellis systems that enhance blackberry fruit yield, fruit quality, and economic viability for fresh-market growers are needed. There are challenges to producing high-quality blackberry fruit with high yields in the Southeast due to intense heat, high rainfall, humidity, and heavy pest pressure. Southeastern growers are interested in the rotating cross-arm (RCA) trellis due to its potential to increase yield and fruit quality, however there is minimal research of its use in blackberry production in the Southeast. In 2019 and 2020, a trial was …

Characterization Of Genetic Sources Associated With Restorability And Seed Dimension In Arkansas Restorer Rice Lines, Ozgur Azapoglu

Graduate Theses and Dissertations

Hybrid rice (Oryza sativa L.) breeding offers a significant opportunity to enhance rice production, and the cultivation of a male sterile line is the most important factor in the success of cross-breeding. One of the key elements of hybrid rice production is to develop a restorer line that is assigned as the male parent. The restorer lines provide viable pollen for fertilization of the male sterile plant due to the presence of a restorer gene (Rf) in their genomes. Any superior restorer line applied to hybrid rice production must contain genes/quantitative trait loci (QTL) associated with the desirable agronomic traits …

Impacts Of Postharvest Temperature Exposure Profiles On Rice Physicochemical Properties, Seth Graham-Acquaah

Graduate Theses and Dissertations

Heated-air drying followed by tempering (HAT) is effective for increasing rough-rice drying rates without compromising head rice yield (HRY). However, heat exposure could affect rice end-use properties. Hypothesizing that the total amount of heat exposure incurred by rice during heated-air drying determines the trend and magnitude of changes in end-use properties, this dissertation sought to 1) characterize the effects of drying and tempering regimen on changes in end-use properties, 2) derive an index to quantify and compare the amount of heat exposure that rice kernels incur during active drying and, 3) relate values of this index to changes in rice …

Application Of X-Ray Imaging And Glass Transition Principles In Understanding Rice Kernel Fissure Formation, Zephania R. Odek

Graduate Theses and Dissertations

Rice kernels with internal fractures of the endosperm, fissures, tend to break during milling, leading to head rice yield (HRY) reductions. Minimizing kernel fissuring is thus an important goal of the rice industry. To minimize fissuring during the drying process, a better understanding of the fissuring process and the kinetics thereof is required. The goal of this research was to use X-ray imaging and glass transition principles to better understand rough rice kernel fissuring. First, because the instance when the fissuring process is initiated and completed during the drying process is not well known, an X-ray imaging setup that allows …

Improving Breeding Program Efficiency And Genetic Gain Through The Implementation Of Genomic Selection In Diverse Wheat Germplasm, Dylan Larkin

Graduate Theses and Dissertations

Genomic selection (GS) is an important tool for increasing genetic gain for economically important traits in breeding programs. Genomic selection uses molecular markers across the entire genome in order to predict the performance of breeding lines for a trait of interest prior to phenotyping. A training population (TP) of elite germplasm, representative of the University of Arkansas wheat breeding program, was developed in order to predict important agronomic and Fusarium head blight (FHB) resistance traits within the University of Arkansas wheat breeding program through cross-validation and forward prediction.

A genome-wide association study (GWAS) was performed on the TP to identify …

Molecular Genetic Analysis Of Drought Resistance And Productivity Traits Of Rice Genotypes, Yheni Dwiningsih

Graduate Theses and Dissertations

Rice (Oryza sativa L.) is the staple food for a majority of the world’s population, and uses 30% of the global fresh water during its life cycle. Drought at the reproductive stage is the most important abiotic stress factor limiting grain yield. The United States is the third largest exporter of rice, and Arkansas is the top rice-producing state. The Arkansas rice-growing region in the Lower Mississippi belt is among the 10 areas with the highest risk of water scarcity. Adapted U.S. rice cultivars were screened for drought resistant (DR) traits to find sources for breeding U.S. rice cultivars for …

Association Mapping For Soybean (Glycine Max L. Merr.) Protein And Oil Content, Joseph Najjar

Graduate Theses and Dissertations

Soybean [Glycine Max (L.) Merrill] is an important economic crop because of its high content of seed protein and oil. Seed oil and protein content are quantitative inherited traits. The genetics of seed protein and oil levels have been extensively studied, with 367 QTL reported for protein and 475 QTL reported for oil to date. Validation of such QTLs, and identification of easily-automatable molecular markers around these QTL will aid the progression of breeding for such traits. The focus of this research was to discover novel and verify previously reported QTL related to protein and/or oil content via Genome-Wide Association …

Can Soil Phosphorus Sorption Saturation Estimate Future Potential Legacy Phosphorus Sources?, A. N. Sharpley, K. R. Brye, J. M. Burke, L G. Berry, M. B. Daniels, P. Webb

Crop, Soil and Environmental Sciences Faculty Publications and Presentations

Various soil extraction methods are used to indicate plant available P in soil but do not account for soil specific sorption of subsequent applications of P. Thus, estimates of soil phosphorus sorption saturation (PSS; estimated from Mehlich-3 extractable P, Al, and Fe) have been used in conjunction with Mehlich-3 extractable soil phosphorus (M3P) to overcome these limitations. As less is known about the effect of land management on PSS than M3P under field conditions, the effect of field management on PSS was investigated for three pastures over 5 yr (2014-2018). Swine slurry was applied to two fields (Field 1 received …

Economic Contribution Of Agriculture And Food To Arkansas' Gross Domestic Product 1997-2019, Leah English, Jennie Popp, Wayne Miller

AAES Research Reports and Research Bulletins

Agricultural production, processing, and retail industries are major contributors to Arkansas’ GDP. Agriculture contributes to the state economy through direct agricultural production, value-added processing, and agricultural retail activities. The Agriculture and Food Sector, which is comprised of agricultural production, processing, and retail industries, promotes economic strength through various interactions with other industries. The use of non-agricultural goods and services as inputs into the agricultural sector promotes diversified growth in Arkansas’ economy and thus plays a vital role in maintaining economic stability throughout the state. This report 1) compares the relative size of the Agriculture and Food Sector in Arkansas with …

The Benefits Of The Arkansas Rice Check-Off Program, B. Peterson-Wilhelm, L. L. Nalley, A. Durand-Morat, A. Shew, R. Parajuli, G. Thoma

AAES Research Reports and Research Bulletins

As margins are reducing for agricultural producers there is a concerted effort to analyze all costs. One such cost for rice producers in Arkansas is their contribution to the Rice Check-off Program. This study analyzes the cost-benefit ratio of funds contributed by Arkansas rice producers and the holistic (both economic and environmental) benefits they receive. This study analyzes just five of the many programs the Rice Check-off Program invests in through the University of Arkansas System Division of Agriculture (UASDA) and suggests that every dollar invested generated an average return of $28.49 between 2002–2018 ($70.45 when ecosystem benefits are included). …

15N Fertilizer Recovery And Partitioning By Cover Crops Under Greenhouse Conditions, Kelsey L.H. Grueb, Trenton L. Roberts

Crop, Soil and Environmental Sciences Faculty Publications and Presentations

Cover crops have the potential to decrease residual-nitrogen (N) losses from agricultural soils by capturing and storing excess N between cash crops. This study was established to assess the effect of cover crop species and N rate on the accumulation and partitioning of biomass and ¹⁵N fertilizer by cover crops produced under controlled environmental conditions. Cereal rye (Secale cereale) and tillage radish (Raphanus sativus) cover crops were grown in monoculture and in a blend under greenhouse conditions in two soils. Urea enriched with ¹⁵N (3.0 atom %) was applied to cover crops at rates …

Rapid Reduction Of Herbicide Susceptibility In Junglerice By Recurrent Selection With Sublethal Dose Of Herbicides And Heat Stress, Lariza Benedetti, Gulab Rangani, Vivian Ebeling Viana, Pamela Carvalho-Moore, Edinalvo Rabaioli Camargo, Luis Antonio De Avila, Nilda Roma-Burgos

Crop, Soil and Environmental Sciences Faculty Publications and Presentations

Global climate change, specifically rising temperature, can alter the molecular physiology of weedy plants. These changes affect herbicide efficacy and weed management. This research aimed to investigate the combined effect of heat stress (HS) and sublethal doses of herbicides (four active ingredients) on adaptive gene expression and efficacy of herbicide on Echinochloa colona (L.) Link (junglerice). Three factors were evaluated; factor A was E. colona generation (G0-original population from susceptible standard; G1 and G2 were progenies of recurrent selection), factor B was herbicide treatment (florpyrauxifen-benzyl, glufosinate-ammonium, imazethapyr, quinclorac and nontreated check) and factor C was HS (30 and 45 °C). …

Response Of Grain Sorghum To Low Rates Of Glufosinate And Nicosulfuron, Hunter Bowman, L. Barber, Jason K. Norsworthy, Trenton L. Roberts, Jason Kelley, Edward E. Gbur

Crop, Soil and Environmental Sciences Faculty Publications and Presentations

Previous research has shown that glufosinate and nicosulfuron at low rates can cause yield loss to grain sorghum. However, research has not been conducted to pinpoint the growth stage at which these herbicides are most injurious to grain sorghum. Therefore, field tests were conducted in 2016 and 2017 to determine the most sensitive growth stage for grain sorghum exposure to both glufosinate and nicosulfuron. Field test were designed with factor A being the herbicide applied (glufosinate or nicosulfuron). Factor B consisted of timing of herbicide application including V3, V8, flagleaf, heading, and soft dough stages. Factor C was glufosinate or …

Arkansas Soybean Research Studies 2019, Jeremy Ross

Arkansas Agricultural Experiment Station Research Series

The 2019 Arkansas Soybean Research Studies includes research reports on topics pertaining to soybean across several disciplines, from breeding to post-harvest processing. Research reports contained in this publication may represent preliminary or only a data set from a single year or limited results; therefore, these results should not be used as a basis for long-term recommendations. Several research reports in this publication will appear in other University of Arkansas System Division of Agriculture’s Arkansas Agricultural Experiment Station publications. This duplication is the result of the overlap in research coverage between disciplines and our effort to inform Arkansas soybean producers of …

Presence Of The Hppd Inhibitor Sensitive 1 Gene And AlsS653n Mutation In Weedy Oryza Sativa Sensitive To Benzobicyclon, Chad Brabham, Jason K. Norsworthy, Fidel Gonzalez-Torralva

Crop, Soil and Environmental Sciences Faculty Publications and Presentations

Benzobicyclon has shown varying results in controlling weedy rice, including those with imidazolinone (IMI) resistance. Tolerance to benzobicyclon in cultivated japonica rice, but not indica or aus-like cultivars, is conferred by a fully functional HPPD Inhibitor Sensitive 1 (HIS1) gene. Herein, a diagnostic Kompetitive Allele Specific PCR (KASP) assay was developed to predict the HIS1 genotype of weedy rice plants from 37 accessions and correlated to their response to benzobicyclon in the field. Two-thirds of the 693 weedy rice plants screened were tolerant to benzobicyclon (371 g ai ha⁻¹, SC formulation) at 30 days after treatment (DAT). …

Seed-Shattering Phenology At Soybean Harvest Of Economically Important Weeds In Multiple Regions Of The United States. Part 1: Broadleaf Species, Lauren M. Schwartz-Lazaro, Lovreet S. Shergill, Jeffrey A. Evans, Muthukumar Bagavathiannan, Shawn C. Beam, Mandy Bish, Jason A. Bond, Kevin A. Bradley, William C. Curran, Adam S. Davis, Wesley J. Everman, Michael L. Flessner, Steven C. Haring, Nicholas R. Jordan, Nicholas E. Korres, John L. Lindquist, Jason K. Norsworthy, Tameka Sanders, Larry E. Steckel, Mark J. Vangessel, Blake Young, Steven B. Mirsky

Crop, Soil and Environmental Sciences Faculty Publications and Presentations

Potential effectiveness of harvest weed seed control (HWSC) systems depends upon seed shatter of the target weed species at crop maturity, enabling its collection and processing at crop harvest. However, seed retention likely is influenced by agroecological and environmental factors. In 2016 and 2017, we assessed seed-shatter phenology in 13 economically important broadleaf weed species in soybean [Glycine max (L.) Merr.] from crop physiological maturity to 4 wk after physiological maturity at multiple sites spread across 14 states in the southern, northern, and mid-Atlantic United States. Greater proportions of seeds were retained by weeds in southern latitudes and shatter rate …

Use Of Florpyrauxifen-Benzyl In Non-Flooded Rice Production Systems, Hannah Wright, Jason K. Norsworthy, Trenton L. Roberts, Robert C. Scott, Jarrod T. Hardke, Edward E. Gbur

Crop, Soil and Environmental Sciences Faculty Publications and Presentations

The lack of a flood on rice (Oryza sativa) levees and in furrow-irrigated rice creates a favorable environment for terrestrial weeds like Palmer amaranth (Amaranthus palmeri S. Wats) to emerge and quickly overtake the crop for a longer portion of the year than in flooded rice culture. Florpyrauxifen-benzyl is a new auxin herbicide labeled for use in rice that has activity on both grasses and broadleaf weeds, as well as certain sedges. Field experiments were conducted to determine the efficacy of florpyrauxifen-benzyl in a non-flooded environment. Experiments were conducted in 2017 and 2018 at the Lon Mann …

Identification Of Quantitative Trait Loci Associated With Canopy Temperature In Soybean, Sumandeep Kaur Bazzer, Larry C. Purcell

Crop, Soil and Environmental Sciences Faculty Publications and Presentations

A consistent risk for soybean (Glycine max L.) production is the impact of drought on growth and yield. Canopy temperature (CT) is an indirect measure of transpiration rate and stomatal conductance and may be valuable in distinguishing differences among genotypes in response to drought. The objective of this study was to map quantitative trait loci (QTLs) associated with CT using thermal infrared imaging in a population of recombinant inbred lines developed from a cross between KS4895 and Jackson. Heritability of CT was 35% when estimated across environments. QTL analysis identified 11 loci for CT distributed on eight chromosomes that …

Quality Of Acid-Preserved Edamame Soybean At Immature And Mature Stages, David Octor Moseley, Leandro Mozzoni, Moldir Orazaly, Liliana Florez-Palacios, Pengyin Chen

Crop, Soil and Environmental Sciences Faculty Publications and Presentations

Edamame is a food-grade soybean that is harvested at the green-immature stage (R6) and sold fresh or frozen for consumption after steaming or boiling. Limited studies have been conducted on high-temperature sterilization of edamame in cans and on acid preservation of edamame. The objectives of this study were to evaluate the color retention and texture of edamame when pasteurized in acidic brine as compared to boiling, to assess the effect of sucrose and turmeric addition on acid-treated edamame, and to characterize varietal differences when edamame lines were pasteurized in an acidic brine at either R6 or R8 stage. All studies …

Physiological And Biochemical Responses Of Two Cotton (Gossypium Hirsutum L.) Cultivars Differing In Thermotolerance To High Night Temperatures During Anthesis, Dimitra A. Loka, Derrick M. Oosterhuis

Crop, Soil and Environmental Sciences Faculty Publications and Presentations

Heat stress constitutes a major threat to crop production, and according to climatic projections, night temperatures are expected to increase faster and to a greater extent compared to day temperatures. While extensive research has been dedicated to the effects of higher than optimum day temperatures on cotton physiology, metabolism, and yield, and while heat-tolerant cotton cultivars have been introduced, the responses of such heat-tolerant cultivars to high night temperatures have not been evaluated. The objective of this study was to assess the efficiency of heat-tolerant cultivars to high night temperatures stress by monitoring the physiological and biochemical responses of two …

Arkansas Wheat Cultivar Performance Tests 2019-2020, R. E. Mason, R. G. Miller, D. E. Moon, J. P. Kelley, J. Carlin

Arkansas Agricultural Experiment Station Research Series

Wheat cultivar performance tests are conducted each year in Ark- ansas by the University of Arkansas System Division of Agriculture’s Arkansas Agricultural Experiment Station, Department of Crop, Soil, and Environmental Sciences. The tests provide informa- tion to companies developing cultivars and marketing seed within the state and aid the Arkansas Cooperative Extension Service in formulating cultivar recommendations for small-grain producers. The tests are conducted at the Northeast Research and Extension Center at Keiser, the Vegetable Substation near Kibler, the Lon Mann Cotton Research Station near Marianna, the Newport Extension Center near Newport, the Rohwer Research Station near Rohwer, the Pine …

Summaries Of Arkansas Cotton Research 2019, Fred Bourland

Arkansas Agricultural Experiment Station Research Series

Statewide, temperatures and precipitation were mostly above average (https://www.weather.gov/lzk/cli2019atxt.htm). The 2019 season was the wettest since 2015, and the 7th wettest on record. The wettest month was May, and the driest month was September. By average temperature, the coldest month was January, and the warmest month was August. Considering departures from normal, the most significant warmth occurred in September, which was 7.0 degrees above average. Many fields were muddy or underwater, given a lot of rain early in the year, and extensive river flooding (including the historic Arkansas River flood). It was far too wet in some areas …

Soybean Growth And Incidence Of Soil-Borne Fungi As Influenced By Metribuzin, Grant L. Priess, Jason K. Norsworthy, Trenton L. Roberts, Terry Neil Spurlock, Edward E. Gbur Jr.

Crop, Soil and Environmental Sciences Faculty Publications and Presentations

Soybean injury following an application of metribuzin soon after planting can occur under cool, wet conditions, especially for varieties that lack a high level of tolerance to the herbicide. Field experiments were conducted in 2017 and 2018 in Fayetteville, AR, to evaluate the impacts of metribuzin at 0, 280, 560, 840, and 1,120 g ai ha⁻¹ on soybean growth and incidence of soil-borne fungi. Three classes of metribuzin tolerance (sensitive, moderately tolerant, and tolerant) were evaluated based on a previous screen. In both years, visible injury to soybean was impacted by varietal tolerance and metribuzin rate. As metribuzin rate …

Irrigated Soybean Response To Granular Fertilizer Potassium Application Timing, Nathan A. Slaton, Trenton L. Roberts, W. Jeremy Ross, Tyler L. Richmond

Crop, Soil and Environmental Sciences Faculty Publications and Presentations

Amelioration of K deficiency during the growing season requires knowledge of critical tissue concentrations and crop yield response to fertilization time. Our objectives were to characterize the yield and uptake responses of K-deficient irrigated soybean [Glycine max (L.) Merr.] to in-season fertilizer-K application time and rate, evaluate fertilizer-potassium-recovery efficiency (FKRE), and evaluate how leaflet-K concentration responds to K-fertilization time. Six trials were established on silt loam soils. Muriate of potash was applied pre-plant and compared to an equivalent K rate applied post-emergence on six or seven dates. Grain yield, trifoliolate-K concentration, and K uptake were measured. Relative soybean yields …

Corn And Soybean Response To Wastewater-Recovered And Other Common Phosphorus Fertilizers, Shane Ylagan, Kristofor R. Brye, Lauren Greenlee

Crop, Soil and Environmental Sciences Faculty Publications and Presentations

Recycling P from wastewaters may provide a sustainable source of P that could also protect surface water quality from P enrichment. Struvite (MgNH₄PO₄·6H₂O) is a material that can be created from P-containing wastewater and has been shown to have agricultural fertilizer value. The objective of this study was to evaluate the effects of electrochemically precipitated struvite (ECST), chemically precipitated struvite (Crystal Green, CG), diammonium phosphate (DAP), monoammonium phosphate (MAP), rock phosphate (RP), and triple superphosphate (TSP) on corn (Zea mays L.) and soybean [Glycine max (L.) Merr.] response in a 79-d greenhouse …

Fate And Transport Of Phosphorus-Containing Land-Applied Swine Slurry In A Karst Watershed, A. N. Sharpley, M. B. Daniels, K. R. Brye, K. Vandevender, J. Burke, L G. Berry, P. Webb

Crop, Soil and Environmental Sciences Faculty Publications and Presentations

Phosphorus distribution in pasture soils underlain with karst geology was determined on a 0.10-ha grid in 2014, 2016, and 2018. Two fields (Fields 1 and 12) received swine slurry from a concentrated animal feeding operation, whereas another (Field 5) received mineral fertilizer. All fields were grazed by cattle and periodically hayed. Mean Mehlich-3 extractable P in the top 10 cm increased (p ≤ .05 level) for Fields 1 (59–91 mg kg⁻¹) and 12 (63–122 mg kg⁻¹) between 2014 and 2018, with little change for Field 5 (45–47 mg kg⁻¹). Over the 5-yr monitoring …

Soil Moisture, Temperature, And Oxidation-Reduction Potential Fluctuations Across A Furrow-Irrigated Rice Field On A Silt-Loam Soil, Diego Della Lunga, Kristofor R. Brye, Jordan M. Slayden, Christopher G. Henry, Lisa S. Wood

Crop, Soil and Environmental Sciences Faculty Publications and Presentations

Alternative water management practices for rice (Oryza sativa) production have been developed for water conservation purposes, such as the furrow-irrigated rice production system, which results in variable volumetric water content (VWC), temperature, and oxidation-reduction (redox) potential conditions. The spatial and temporal variations in environmental factors can affect greenhouse gas (GHG) emissions. The objective of this field study was to document and evaluate the continuous variations in soil water content, temperature, and redox potential over two growing seasons (2018 and 2019) among site positions (up-, mid-, and down-slope) and tillage treatments [conventional tillage (CT) and no-tillage (NT)] under furrow-irrigated …

Water Management Effects On Trace Gas Emissions Under Greenhouse Conditions From Direct-Seeded Hybrid Rice In A Silt-Loam Soil, Diego Della Lunga, Kristofor R. Brye, Trenton L. Roberts, Shelby G. Lebeau

Crop, Soil and Environmental Sciences Faculty Publications and Presentations

Water management regimes influence greenhouse gas emissions in rice (Oryza sativa L.) production. The objective of this study was to quantify methane (CH4 ), nitrous oxide (N2 O), and carbon dioxide (CO2 ) under direct-seeded conditions in the greenhouse to evaluate the effects of water regime on fluxes and growing-season-long emissions. Research was conducted during 2019 using a hybrid rice cultivar (RT 7311 CL) grown in a DeWitt silt loam (Albaqualf). Six plastic tubs, filled with 21 kg of soil and manually seeded, were arranged in a completely random design with two replications of three water regime treatments: i) flooded, …

B.R. Wells Arkansas Rice Research Studies 2019, K.A. K. Moldenhauer, B. Scott, J. Hardke

Arkansas Agricultural Experiment Station Research Series

No abstract provided.

Profit-Maximizing Potassium Fertilizer Recommendations For Soybean, Michael P. Popp, Nathan A. Slaton, Trenton L. Roberts

Crop, Soil and Environmental Sciences Faculty Publications and Presentations

Potassium (K) fertilizer has important yield and cost ramifications in soybean [Glycine max (L.) Merr.] production. Rate recommendations are often based on expected yield response as predicted by a soil test. To that end, soybean response to K application rate studies were analyzed using 86 site-years from 2004 to 2019. We estimated a generic yield response curve across soybean cultivar and soil texture to allow calculation of profit-maximizing K rates for producers in the mid-southern United States that also consider crop value and fertilizer cost. Further, we compared profit-maximizing fertilizer-K rates with those currently recommended. Using a spreadsheet-based decision …