Agronomy and Crop Sciences Commons^™

Assessing Consumer Demand, Producer Profitability, And The Environmental Impacts Of Conservation Agriculture Adoption In Sub-Saharan Africa, Willy Byamungu Mulimbi

Graduate Theses and Dissertations

This dissertation explores three aspects of conservation agriculture (CA) in the Sub-Saharan African region (SSA). The first article examines the demand side of CA and explores whether urban maize (Zea mays L.) consumers in the Democratic Republic of the Congo (DRC) would be willing to pay a premium for CA-produced maize flour. The second article estimates the effects CA provides to adopters and their farms in smallholder farming systems in the DRC, focusing on changes in soil properties and cowpea (Vigna unguiculata) yields. The final article uses a Life Cycle Assessment (LCA) approach to monetize the environmental impacts of adopting …

Optimization Techniques For Soil Organic Carbon Prediction Using Mid-Infrared Spectroscopy, Minerva J. Dorantes

Graduate Theses and Dissertations

Resource-efficient techniques for accurate soil carbon estimation are necessary to satisfy the increasing demand for spatiotemporal data. In the last thirty years, mid-infrared (MIR) soil spectroscopy has developed as an accurate, rapid, cost-effective, and non-destructive technique for soil organic carbon (SOC) analysis. In soil spectroscopy, a calibration model relates spectral data to a corresponding measured soil property and is subsequently used to predict this value from new spectral data. Various optimization techniques have been used to improve the statistical performance of calibrations; however, there is little consensus on the conditions that make these techniques effective. The objectives of this research …

Effect Of Irrigation Regime And Fertilization On Recovery Of Dicamba Injured Soybean, Wesley France, Jason K. Norsworthy, Trenton Roberts, Jeremy Ross, L. Tom Barber, Edward E. Gbur

Crop, Soil and Environmental Sciences Faculty Publications and Presentations

With the release of the dicamba-resistant crop technology and subsequent increase in dicamba off-target movement to non-dicamba-resistant crops, discovering means of mitigating yield loss through studying dicamba injury to soybean and interactions with factors such as irrigation regime and fertilization would prove beneficial. Field experiments were conducted in 2019 in Fayetteville and Colt, Arkansas, to evaluate the effect of irrigation regime to non-dicamba-resistant soybean that was injured by dicamba at a low dose at multiple timings. Another experiment was conducted in Fayetteville in 2019 and 2020 evaluating the impact of nitrogen (N) and potassium (K) fertilization on soybean recovery following …

Effect Of Cultivar And Planting Date On Soybean Response To Dicamba, Wesley France, Jason K. Norsworthy, Trenton Roberts, Jeremy Ross, L. Tom Barber, Edward E. Gbur

Crop, Soil and Environmental Sciences Faculty Publications and Presentations

Off-target movement of dicamba has been blamed for damaging millions of hectares of soybean in the United States since registration of the herbicide for use in dicamba-resistant cotton and soybean. Understanding the effect of a low dose of dicamba on non-dicamba-resistant soybean across multiple cultivars, growth stages, and planting dates could help producers better understand the implication of current management practices on yield loss from dicamba in fields where non-dicamba-resistant soybean are grown. A field experiment was conducted in 2019 in Fayetteville and Stuttgart, Arkansas, to evaluate the impact of planting date on response of soybean to a low dose …

Palmer Amaranth Control In Furrow-Irrigated Rice With Florpyrauxifen-Benzyl, James Winston Beesinger, Jason K. Norsworthy, Thomas R. Butts, Trenton L. Roberts

Crop, Soil and Environmental Sciences Faculty Publications and Presentations

Palmer amaranth is a common weed on levees in rice fields but has become increasingly problematic with the adoption of furrow-irrigated rice and lack of an established flood. Florpyrauxifen-benzyl previously has been found effective for controlling Palmer amaranth in rice, but the efficacy of low rates of florpyrauxifen-benzyl and the effect of Palmer amaranth size on controlling it is unknown. The objective of this research was to determine the level of Palmer amaranth control expected with single and sequential applications of florpyrauxifen-benzyl at varying weed heights. The first study was conducted near Marianna, AR, in 2019 and 2020, to determine …

Benzobicyclon For Weedy Rice Control In Quizalofop- And Imidazolinone-Resistant Rice Systems, Jake A. Patterson, Jason K. Norsworthy, Thomas R. Butts, Edward E. Gbur

Crop, Soil and Environmental Sciences Faculty Publications and Presentations

Gowan Company recently registered benzobicyclon, a WSSA Group 27 herbicide, as a postflood option in rice. It is the first 4-hydroxyphenylpyruvate dioxygenase-inhibiting herbicide commercially available in mid-southern U.S. rice production. In 2018 and 2019, field experiments were conducted across multiple sites in Arkansas to determine if the addition of benzobicyclon to quizalofop- or imidazolinone-resistant rice herbicide programs would improve weedy rice control. Across site-years, one application of quizalofop, either at the 1- or 3-leaf rice stage, followed by benzobicyclon applied postflood, provided comparable weedy rice control to two sequential applications of quizalofop, which is a standard herbicide program in quizalofop-resistant …

Optimizing Weed Control Using Dicamba And Glufosinate In Eligible Crop Systems, Grant Lawson Priess, Michael P. Popp, Jason K. Norsworthy, Andronikos Mauromostakos, Trenton L. Roberts, Thomas R. Butts

Crop, Soil and Environmental Sciences Faculty Publications and Presentations

A field experiment was conducted in 2019 and 2020 that included six site-years and four locations in Arkansas to determine the optimal sequence and timing of dicamba and glufosinate applications when applied alone, sequentially, or in combination to control Palmer amaranth by size: labeled (<10 cm height) and non-labeled (13 to 25 cm height). Single applications of dicamba, glufosinate, and dicamba plus glufosinate (not labeled) resulted in less than 80% Palmer amaranth control, regardless of weed size. The mixture of dicamba plus glufosinate was antagonistic for Palmer amaranth control and percent mortality. Sequential applications, averaged over all time intervals and herbicides, improved the percentage of Palmer amaranth control 11 to 17 percentage points over a single application, regardless of weed size at application 28 d after final application (DAFA). Palmer amaranth control with glufosinate followed by (fb) glufosinate and dicamba fb dicamba, pending weed size, were optimized at intervals of 7 d, and 14 to 21 d, respectively. Because single site of action (SOA) postemergence herbicide systems increase the likelihood of the development of resistant biotypes and are not a best management practice (BMP) in that regard; sequential applications involving both dicamba and glufosinate were more effective. Furthermore, the sequence of application mattered with a preference for applying dicamba first. Dicamba fb glufosinate at a 14-d interval was profit-maximizing and the only herbicide treatment that resulted in 100% weed control when size was <10 cm. For larger weed sizes, economic analysis revealed that dicamba fb dicamba performed better than dicamba fb glufosinate when no penalty was assigned for using a single SOA. This resulted in greater yield loss risk and soil weed seed bank in comparison to timelier weed control with the smaller weed size. Hence, timely weed control and two SOAs to control Palmer amaranth are recommended as BMPs that reduce producer risk.

Assessment Of Struvite As An Alternative Sources Of Fertilizer-Phosphorus For Flood-Irrigated Rice, Kristofor R. Brye, Niyi Sunday Omidire, Leah Ashley English, Ranjan Parajuli, Laszlo Kekedy-Nagy, Ruhi Sultana, Jennie Popp, Greg Thoma, Trenton L. Roberts, Lauren F. Greenlee

Crop, Soil and Environmental Sciences Faculty Publications and Presentations

Phosphorus (P) recovery from wastewaters as struvite (MgNH4PO4 center dot 6H(2)O) may be a viable alternative fertilizer-P source for agriculture. The objective of this study was to evaluate the economic and environmental implications of struvite as a fertilizer-P source for flood-irrigated rice (Oryza sativa) relative to other commonly used commercially available fertilizer-P sources. A field study was conducted in 2019 and 2020 to evaluate the effects of wastewater-recovered struvite (chemically precipitated struvite (CPST) and electrochemically precipitated struvite (ECST)) on rice yield response in a P-deficient, silt-loam soil in eastern Arkansas relative to triple superphosphate, monoammonium and diammonium phosphate, and rock …

B.R. Wells Arkansas Rice Research Studies 2021, J. Hardke, X. Sha, N. Bateman

Arkansas Agricultural Experiment Station Research Series

Arkansas is the leading rice producer in the United States. The state represents 47.5% of total U.S. rice production and 47.8% of the total acres planted to rice in 2021. Rice cultural practices vary across the state and across the U.S. However, these practices are also dynamic and continue to evolve in response to changing political, environmental, and economic times. This survey was initiated in 2002 to monitor and record changes in the way Arkansas rice producers approach their livelihood. The survey was conducted by polling county extension agents in each of the counties in Arkansas that produce rice. Questions …

An Economic Analysis Of A Case Farm Involved In Hemp Production For Cbd At Small Scale, Benjamin Daniel Joost Jacobs

Graduate Theses and Dissertations

This thesis is comprised of studies examining cost of production differences between outdoor (open-air) and indoor (greenhouse) production of hemp flower on a small-scale hemp farm. Investigated also are oil extraction processes as well as drying costs and methods i) under controlled ambient conditions (air-drying) for 14 days at 65-70°F and 45-60% ambient humidity, ii) using infrared radiation (IR) for varying durations at an intensity of 2.51 kW per square meter, and iii) freeze-drying or lyophilization based on literature review. Critically, these drying methods involve tradeoffs related to time required, amount of energy consumed, and investment required. Also, they impact …

Evaluation Of Factors That Contribute To Injury To Quizalofop-Resistant Rice From Quizalofop Applied Postemergence, Navdeep Godara

Graduate Theses and Dissertations

Quizalofop-resistant rice technology allows for over-the-top applications of quizalofop, an acetyl-coenzyme A carboxylase-inhibiting herbicide. However, quizalofop caused significant injury to quizalofop-resistant rice in some Arkansas fields during the first year of commercialization. Experiments evaluated the effect of early-season soil moisture and nitrogen availability; pre-exposure to low rates of glyphosate and imazethapyr; planting date; and environmental conditions including, soil moisture content, air temperature, and light intensity on quizalofop-resistant rice tolerance to quizalofop applications. All experiments assessed sequential quizalofop applications made to 2-leaf followed by 5-leaf stage of rice. Sequential quizalofop applications alone and with surface irrigation or nitrogen application at the …

Investigating Hops Production In Arkansas To Support Specialty Crop Growth, James Oliver Mcclellan

Graduate Theses and Dissertations

The hop plant (Humulus lupulus L.) is a perennial, climbing species within the Cannabaceae family that produces cones used for brewing. Hops are grown worldwide. In the United States most hops production occurs in the Pacific Northwest, but growth in the craft beer industry is driving efforts for hops production in other U.S. regions. Recommendations on hops cultivar suitability, fertility, and management are needed for the U.S. mid-south region. Objectives of this research on Arkansas-grown hops were to 1) assess the impact of cultivar and fertility rate on plant and cone attributes of six cultivars of Arkansas-grown hops and 2) …

Application Of Microwave-Assisted Technology For Single-Pass Drying Of Rough Rice, Rebecca Mawusi Bruce

Graduate Theses and Dissertations

The 915 MHz industrial microwave is a novel technology that has the potential to achieve one-pass drying of rice within a short drying duration and reduce rice drying losses. However, processing recommendations for the commercialization of this technology for rice drying is lacking. The goal of this research is to provide processing conditions that are useful for the commercialization of the 915 MHz industrial microwave technology for rice drying. This was achieved by studying the impact of microwave specific energy and processing conditions such as harvest moisture content, milling duration, and aging on the physicochemical properties of a 915 MHz …

The Effect Of Water Management And Ratoon Rice Cropping On Methane Emissions And Harvest Yield In Arkansas, Marguerita Leavitt

Graduate Theses and Dissertations

Sustainable intensification of rice farming is crucial to meeting human food needs while reducing environmental impacts. Rice produces 8% of all anthropogenic CH4, which is a potent greenhouse gas. CH4 emissions can potentially be reduced by cultivation practices that minimize the number of days the fields are saturated, such as dry-seeding instead of water-seeding and irrigation using the alternate wetting and drying (AWD) technique instead of delayed, continuous flooding (DF). Ratoon cropping, wherein a second crop of rice is grown from the harvested stubble of the first crop, can be used to produce additional yield with minimal labor, but may …

International Rice Outlook: International Rice Baseline Projections 2021–2031, A. Durand-Morat, S. Bairagi

AAES Research Reports and Research Bulletins

The war in Ukraine and the lingering effects of the COVID-19 pandemic are pushing input costs to record levels. Although rice prices have increased some in the last several months, production costs have increased more than proportionally, undermining rice profitability.

We project global rice production will surpass global rice consumption for most of the coming decade, with a small deficit developing by the end of the projected period.

The projected growth in production is almost exclusively due to productivity gains since the global rice area is projected to increase only marginally by 2029–2031.

The projected growth in global rice consumption …

Unraveling The Mechanism Of Resistance In A Glufosinate-Resistant Palmer Amaranth (Amaranthus Palmeri) Accession, Pamela Carvalho-Moore, Jason K. Norsworthy, Fidel Gonzalez-Torralva, Jeong-In Hwang, Jinesh D. Patel, L. Tom Barber, Thomas R. Butts, J. Scott Mcelroy

Crop, Soil and Environmental Sciences Faculty Publications and Presentations

Glufosinate resistance in Palmer amaranth (Amaranthus palmeri S. Watson) was recently detected in three accessions from Arkansas, USA. Amaranthus palmeri is the first and only broadleaf weed species resistant to this herbicide, and the resistance mechanism is still unclear. A previous study characterized the glufosinate resistance level in the accessions from Arkansas. A highly glufosinate-resistant accession was further used to investigate the mechanism conferring glufosinate resistance in A. palmeri. Experiments were designed to sequence the herbicide target enzyme cytosolic and chloroplastic glutamine synthetase isoforms (GS1 and GS2, respectively) and quantify copy number and expression. Absorption, translocation, and metabolism of glufosinate …

Calibration Set Optimization And Library Transfer For Soil Carbon Estimation Using Soil Spectroscopy - A Review, Minerva J. Dorantes, Bryan A. Fuentes, David M. Miller

Crop, Soil and Environmental Sciences Faculty Publications and Presentations

Resource-efficient techniques for accurate soil property estimation are necessary to satisfy the increasing demand for soil data to support environmental monitoring, precision agriculture, and spatial modeling. Over the last 30 yr, infrared soil spectroscopy has developed into a rapid, robust, and cost-effective technique for soil carbon analysis. Ongoing global efforts to make soil spectroscopy operational require the development of soil spectral libraries, which are the main source of data for the construction of calibration models. Understanding calibration optimization is important to ensure the efficient use of soil spectral libraries for the accurate estimation of soil carbon. Moreover, spectral library transfer …

Arkansas Corn And Grain Sorghum Research Studies 2021, Victor Ford, Jason Kelley, Nathan Mckinney Ii

Arkansas Agricultural Experiment Station Research Series

The 2021 edition of the Arkansas Corn and Grain Sorghum Research Studies Series includes research results on topics pertaining to corn and grain sorghum production, including weed, disease, and insect management; economics; sustainability; irrigation; post-harvest drying; soil fertility; mycotoxins; cover crop management; and research verification program results. Our objective is to capture and broadly distribute the results of research projects funded by the Arkansas Corn and Grain Sorghum Board. The intended audience includes producers and their advisors, current investigators, and future researchers. The Series serves as a citable archive of research results.

Resistance Of Palmer Amaranth (Amaranthus Palmeri) To S-Metolachlor In The Midsouthern United States, Koffi Badou Jeremie Kouame, Matthew B. Bertucci, Mary C. Savin, Taghi Bararpour, Lawrence E. Steckel, Thomas R. Butts, Cammy D. Willett, Fellipe G. Machado, Nilda R. Burgos

Crop, Soil and Environmental Sciences Faculty Publications and Presentations

Palmer amaranth (Amaranthus palmeri S. Watson) is one of the most problematic weeds in many cropping systems in the midsouthern United States because of its multiple weedy traits and its propensity to evolve resistance to many herbicides with different mechanisms of action. In Arkansas, A. palmeri has evolved metabolic resistance to S-metolachlor, compromising the effectiveness of an important weed management tool. Greenhouse studies were conducted to evaluate the differential response of A. palmeri accessions from three states (Arkansas, Mississippi, and Tennessee) to (1) assess the occurrence of resistance to S-metolachlor among A. palmeri populations, (2) evaluate the resistance level …

Wastewater-Recycled Struvite As A Phosphorus Source In A Wheat-Soybean Double-Crop Production System In Eastern Arkansas, Niyi Sunday Omidire, Kristofor R. Brye

Crop, Soil and Environmental Sciences Faculty Publications and Presentations

Fertilizer-phosphorus (P) sources are mainly derived from rock phosphate (RP), which is a finite, actively mined resource. With growing human populations globally, alternative P sources are vitally important to ensure future food security. Precipitation of the mineral struvite (MgNH₄PO₄·6H₂O) from wastewater could be a potential alternative fertilizer-P option from crop production. The objective of this study was to evaluate the effects of chemically precipitated struvite (CPST), compared with triple superphosphate (TSP) and an unamended control (UC) treatment, and irrigation (irrigated and non-irrigated/dryland) on above- (dry matter, yield, and tissue-N, -P, and -Mg concentrations and …

Can Double Ppo Mutations Exist In The Same Allele And Are Such Mutants Functional?, Aimone Porri, Matheus M. Noguera, Michael Betz, Daniel Salinger, Frank Brandle, Steven J. Bowe, Jens Lerchl, Lucie Meyer, Michael Knapp, Nilda Roma-Burgos

Crop, Soil and Environmental Sciences Faculty Publications and Presentations

BACKGROUND

Resistance to protoporphyrinogen oxidase (PPO)-inhibiting herbicides is endowed primarily by target-site mutations at the PPX2 gene that compromise binding of the herbicide to the catalytic domain. In Amaranthus spp. PPX2, the most prevalent target mutations are deletion of the G210 codon, and the R128G and G339A substitutions. These mutations strongly affect the dynamic of the PPO2 binding pocket, resulting in reduced affinity with the ligand. Here we investigated the likelihood of co-occurrence of the most widespread target site mutations in the same PPX2 allele.

RESULTS

Plants carrying R128G+/+ ΔG210+/−, where + indicates presence of the mutation, were crossed …

Utility Of Roller Wiper Applications Of Dicamba For Palmer Amaranth Control In Soybean, Rodger Bruce Farr, Jason K. Norsworthy, L. Tom Barber, Thomas R. Butts, Trenton Roberts

Crop, Soil and Environmental Sciences Faculty Publications and Presentations

BACKGROUND

The commercialization of dicamba-resistant soybean has resulted in increased concern for off-target movement of dicamba onto sensitive vegetation. To mitigate the off-target movement through physical drift, one might consider use of rope wicks and other wiper applicators. Although wiper-type application methods have been efficacious in pasture settings, the utility of dicamba using wiper applicators in agronomic crops is not available in scientific literature. To determine the utility of roller wipers for dicamba applications in dicamba-resistant soybean, two separate experiments were conducted in the summer of 2020 and replicated in both Keiser and Fayetteville, AR, USA.

RESULTS

Utilizing opposing application …

Field-Evolved Δg210-Ppo2 From Palmer Amaranth Confers Pre-Emergence Tolerance To Ppo-Inhibitors In Rice And Arabidopsis, Pamela Carvalho-Moore, Gulab Rangani, Ana Claudia Langaro, Vibha Srivastava, Aimone Porri, Steven J. Bowe, Jens Lerchl, Nilda R. Burgos

Crop, Soil and Environmental Sciences Faculty Publications and Presentations

Resistance to protoporphyrinogen IX oxidase (PPO)-inhibitors in Amaranthus palmeri and Amaranthus tuberculatus is mainly contributed by mutations in the PPO enzyme, which renders herbicide molecules ineffective. The deletion of glycine210 (ΔG210) is the most predominant PPO mutation. ΔG210-ppo2 is overexpressed in rice (Oryza sativa c. ‘Nipponbare’) and Arabidopsis thaliana (Col-0). A foliar assay was conducted on transgenic T1 rice plants with 2× dose of fomesafen (780 g ha−1), showing less injury than the non-transgenic (WT) plants. A soil-based assay conducted with T2 rice seeds confirmed tolerance to fomesafen applied pre-emergence. In agar medium, root growth of WT …

Targeting Tor And Snrk1 Genes In Rice With Crispr/Cas9, Bhuvan Pathak, Chandan Maurya, Maria C. Faria, Zahra Alizada, Soumen Nandy, Shan Zhao, Muhammed Jamsheer K, Vibha Srivastava

Crop, Soil and Environmental Sciences Faculty Publications and Presentations

Genome targeting with CRISPR/Cas9 is a popular method for introducing mutations and creating knock-out effects. However, limited information is currently available on the mutagenesis of essential genes. This study investigated the efficiency of CRISPR/Cas9 in targeting rice essential genes: the singleton TARGET OF RAPAMYCIN (OsTOR) and the three paralogs of the Sucrose non-fermenting-1 (SNF1)-related kinase 1 (OsSnRK1α), OsSnRK1αA, OsSnRK1αB and OsSnRK1αC. Strong activity of constitutively expressed CRISPR/Cas9 was effective in creating mutations in OsTOR and OsSnRK1α genes, but inducible CRISPR/Cas9 failed to generate detectable mutations. The rate of OsTOR mutagenesis was relatively lower and only the …

Investigating The Mechanics And Chemistry Of Sickle Polish Development, Justin Jared Dubois

Graduate Theses and Dissertations

This series of experiments is designed to understand the development and chemistry of sickle gloss. Sickles are common in the archaeological record and have long been studied for their eponymous “sickle gloss”. There is debate as to how this gloss is formed. Five experimental sickles containing flint and novaculite blades were used to harvest high and low moisture content rye and common fescue and associated field weeds. The differences in the development of sickle gloss were examined. High moisture content plants create thick, smooth fields of polish with undulating, billowing margins at a higher developmental speed. Low moisture content plants …

An Investigation Of Factors Affecting The Rooting Ability Of Hardwood Muscadine Cuttings And Genetic Diversity Of Wild And Cultivated Muscadine Grapes (Vitis Rotundifolia Michx.), Kenneth Buck

Graduate Theses and Dissertations

The muscadine (Vitis rotundifolia syn. Muscadinia rotundifolia) is a grape species native to the southeastern United States. Muscadines are one of three grape species in subgenus Muscadinia with a chromosome number of 2n=40 (V. rotundifolia, V. munsoniana, and V. popenoei), making them genetically distinct from the European wine and table grape (Vitis vinifera) and other species in subgenus Euvitis. Rooting hardwood cuttings from muscadine vines has traditionally been considered an exceptionally difficult task. Many previous studies observed almost no root formation, leading to a general consensus that muscadines should either be propagated by softwood cuttings or vegetative layering. However, the …

Economic Viability Of Weed Management Strategies In High-Tunnel Tomato, Gracie Morrison

Crop, Soil and Environmental Sciences Undergraduate Honors Theses

Cost-effective weed suppression is an important consideration for tomato growers. Growers often choose methods which minimize hand labor, as hand weeding can be prohibitively expensive. This project determined economic viability of high tunnel tomatoes treated with several methods of weed control, both organic and chemical. These methods included: 2-week hand weeding, 1-week hand weeding, preemergent, straw, landscape fabric, and untreated weedy control plots. These treatments were applied to randomized blocks in a high-tunnel. Weeding, planting, and harvest were all timed to determine labor and material costs of weed management strategy implementation. After harvest, marketable yield was weighed to determine revenue. …

Effects Of One-Pass Microwave Drying On Rice’S Utilization In The Brewing Process., Christopher Stuckey

Food Science Undergraduate Honors Theses

Rice is utilized as an adjunct grain by the beer manufacturing industry. Before utilization, the rice has to be dried to a desired moisture content. The drying process employed may have an impact on the rice’s physicochemical properties which influence the rice’s performance in the brewing process. This study focused on investigating the impact of microwave drying on rice’s physicochemical properties and utilization in the brewing process. Rough rice samples at an initial moisture content of 19.7% wet basis were exposed to microwave dryer set to deliver 525 kJ/kg of energy in a single drying pass. The effects of the …

Impact Of Delaying Irrigation On Wilting, Seed Yield, And Other Agronomic Traits Of Determinate Mg5 Soybean, Francia Ravelombola, Andrea Acuna, Liliana Florez-Palacios, Chengjun Wu, Derrick Harrison, Maria De Oliveira, Joshua Winter, Marcos Da Silva, Trenton Roberts, Christopher Henry, Fernando Grignola, Ehsanollah Shakiba, Leandro Mozzoni

Crop, Soil and Environmental Sciences Faculty Publications and Presentations

Soybean production in the U.S. Mid-South relies heavily on irrigation with 85% of soybean surfaces irrigated in Arkansas. Reduction in irrigation due to water quantity restrictions will significantly affect soybean seed yield, making variety selection increasingly important. The objective of the study was to assess if irrigation onsets at different reproductive stages affect wilting, seed yield, and key agronomic traits on determinate maturity group 5 (MG 5) soybean. One-hundred sixty-five F₄-derived populations of recombinant inbred lines with determinate growth habit, similar maturity, and contrasting wilting potential were planted in an augmented strip-plot design in four environments as a …

Managing Stress Tolerance On Warm-Season Putting Greens In The Transition Zone, Thomas Edward Walton

Graduate Theses and Dissertations

The use of warm-season putting greens in the transition zone has increased in recent years. Ultradwarf bermudagrass (Cynodon dactylon (L.) Pers x C. transvaalensis Burtt-Davy) is the most prevalent warm-season putting green selection in the transition zone, however, newly developed greens-type zoysiagrass (Zoysia spp.) cultivars represent another potential selection for golf courses. The two major limitations of warm-season grasses in the transition zone are a general lack of cold- and shade-tolerance. Protective covers are essential to protect ultradwarf bermudagrass putting greens in the winter months. Unfortunately, golf courses can still experience winterkill underneath protective covers. Two field trials were conducted …