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Developing Recommendations For Broad Mite, Polyphagotarsonemus Latus Banks, In Blackberry, Rubus Subgenus Rubus, Jared Bradley Linn Dec 2023

Developing Recommendations For Broad Mite, Polyphagotarsonemus Latus Banks, In Blackberry, Rubus Subgenus Rubus, Jared Bradley Linn

Graduate Theses and Dissertations

Broad mite, (Polyphagotarsonemus latus Banks) (Acari: Tarsonemidae), is an economically important pest of blackberry production across the world. Since it was first reported on primocane-fruiting blackberries in 2010, little work has gone into developing IPM tools and understanding impact on floricane-fruiting cultivars. The objective of this thesis was to evaluate the effect of broad mite feeding on floricane-fruiting cultivars of blackberry, develop an efficient and accurate field scouting strategy, and investigate the impact of cultivar and trellising technique on the development of broad mite populations. Experiments consisted of evaluating floricane fruiting cultivars by quantifying broad mite populations and cataloging their …


Cellular Control Of Proteostasis, Cytoskeleton Organization, And Polarity Remodeling During Infection-Related Development By The Rice Blast Fungus, Audra Rogers Dec 2023

Cellular Control Of Proteostasis, Cytoskeleton Organization, And Polarity Remodeling During Infection-Related Development By The Rice Blast Fungus, Audra Rogers

Graduate Theses and Dissertations

Understanding the intricate processes underlying fungal infection-related development is crucial for combating plant pathogens. In this study, we investigate the coordination of morphogenetic transitions during plant infection by Magnaporthe oryzae, the blast fungus. We focus on three key aspects: protein quality control, cytoplasmic microtubule organization, and cell-end marker proteins. M. oryzae forms a specialized infection cell known as an appressorium. The proper formation of this cell is crucial for the pathogen to infect a susceptible host. First, we investigate protein quality control mechanisms during infection-related development. Our findings demonstrate that aggregated proteins are sequestered into quality control compartments within conidia …


Evaluation Of Water Hardness And Ph On Soybean And Cotton Insecticide Efficacy, Taylor Davis Dec 2023

Evaluation Of Water Hardness And Ph On Soybean And Cotton Insecticide Efficacy, Taylor Davis

Graduate Theses and Dissertations

Insecticide efficacy often varies by location and year. Many factors can influence an insecticide’s efficacy, but an often-overlooked factor is the quality of water in a carrier solution. Water quality includes many parameters, but two important ones are water hardness and pH. Research has shown that water hardness and pH can affect some pesticides. Multiple experiments were conducted to evaluate the impact of water hardness and pH on insecticide efficacy. Experiments were conducted to evaluate the impact of water hardness and pH on the efficacy and residual control of chlorantraniliprole for the control of corn earworm, Helicoverpa zea (Boddie). Leaf …


Environmental And Agronomic Evaluation Of Struvite In Rice Production Systems, Diego Della Lunga Dec 2023

Environmental And Agronomic Evaluation Of Struvite In Rice Production Systems, Diego Della Lunga

Graduate Theses and Dissertations

Furrow-irrigation constitutes an alternative water regime that has been increasingly adopted in Arkansas. Among the management of nutrients in furrow-irrigated systems, phosphorus (P) represents a substantial challenge. The environmental sustainability of rice (Oryza sativa) production systems needs to be evaluated across different water regimes and fertilizer-P sources. Therefore, the objectives of the following studies were to: i) evaluate season-long carbon dioxide (CO2) and methane (CH4) emissions and global warming potential (GWP) under different tillage treatments [i.e., conventional tillage (CT) and no-tillage (NT)] and at different site positions (i.e., up-, mid-, down-slope) along the predominant slope of a production-scale, furrow-irrigated rice …


Evaluation Of Weed Control Efficacy And Crop Tolerance To Florpyrauxifen-Benzyl Coated Onto Urea, Bodie Lyn Cotter Dec 2023

Evaluation Of Weed Control Efficacy And Crop Tolerance To Florpyrauxifen-Benzyl Coated Onto Urea, Bodie Lyn Cotter

Graduate Theses and Dissertations

Frequent off-target movement occurrences to soybean [Glycine max (L.) Merr.], rice (Oryza sativa L.) injury, and a lack of barnyardgrass [Echinochloa crus-galli (L.) P. Beauv.] control followed the commercial launch of florpyrauxifen-benzyl in 2018. Florpyrauxifen-benzyl is a synthetic auxin, Herbicide Resistance Action Committee (HRAC)/Weed Science Society of America (WSSA) Group 4 herbicide used for postemergence weed control in rice and labeled for application at 30 g ae ha-1. Previous research documented that soybean was susceptible to injury following spray applications of florpyrauxifen-benzyl at less-than-labeled rates, and certain varieties of rice are less tolerant to spray-applied florpyrauxifen-benzyl at 30 g ae …


Management Zone Delineation For Variable-Rate Seeding In Production Soybeans, Ujjwal Sigdel Dec 2023

Management Zone Delineation For Variable-Rate Seeding In Production Soybeans, Ujjwal Sigdel

Graduate Theses and Dissertations

Soybean seeding rate (SR) is selected according to planting date, maturity group, soil properties, and yield goal. Even though one SR is applied in most fields, site-specific adjustments with variable-rate seeding (VRS) technology can help optimize production. The project goal was to determine if VRS could be beneficial to soybean producers in Arkansas. The project objectives were to i) assess planter performance and soybean yield response to five seeding rate treatments, ii) characterize the drivers of yield variability, and iii) create a-posteriori prescription maps for VRS. Five SR treatments (185,000, 247,000, 309,000, 370,000 and 432,000 seeds ha-1) were applied using …


Evaluation Of Oxyfluorfen For Use In Roxy Rice, Casey Hunter Arnold Dec 2023

Evaluation Of Oxyfluorfen For Use In Roxy Rice, Casey Hunter Arnold

Graduate Theses and Dissertations

Mid-southern U.S. rice (Oryza sativa L.) producers are challenged every year to control problematic barnyardgrass [Echinochloa crus-galli (L.) Beauv.] and weedy rice (Oryza sativa L.) because they have evolved resistance to most labeled herbicides. Oxyfluorfen is a Herbicide Resistance Action Committee (HRAC)/Weed Science Society of America (WSSA) Group 14 herbicide that inhibits protoporphyrinogen oxidase within the plant. Currently, there are no HRAC/WSSA Group 14 herbicides labeled for barnyardgrass or weedy rice control in midsouthern rice production. Therefore, oxyfluorfen is being evaluated for barnyardgrass and weedy rice control. Plant breeders at the University of California – Davis were able to breed …


Effect Of Cultural Strategies And Application Technologies On Weed Control In Flooded And Furrow-Irrigated Rice, Noah Hunter Reed Dec 2023

Effect Of Cultural Strategies And Application Technologies On Weed Control In Flooded And Furrow-Irrigated Rice, Noah Hunter Reed

Graduate Theses and Dissertations

Weed control is a major problem that rice (Oryza sativa L.) producers face in the Mid-south every growing season. Restricted use of some rice herbicides has also highlighted the need for more research to be conducted on cultural weed control strategies and application technologies in rice. The aim of these studies was to evaluate rice weed control using various rice row widths, bed widths (irrigation-furrow spacing), rice cultivar selection, and nozzle type selection. Three field experiments were conducted in 2021 and 2022 across four sites at Lonoke, AR, Pine Tree, AR, Rohwer, AR, and Stoneville, MS. In experiment one, as …


Assessing The Evaporation Method For Soil-Water Retention Curve Development And Comparison Of Soil-Water Characteristics Across Different Tillage Practices In A Furrow-Irrigated Corn (Zea Mays L.) System, Jeferson Prass Pimentel Dec 2023

Assessing The Evaporation Method For Soil-Water Retention Curve Development And Comparison Of Soil-Water Characteristics Across Different Tillage Practices In A Furrow-Irrigated Corn (Zea Mays L.) System, Jeferson Prass Pimentel

Graduate Theses and Dissertations

The thesis comprises three studies. The first study in this thesis (Chapter I) focused on a six-year corn field experiment to assess the influence of conservation agricultural practices on soil properties and their long-term effects on water-use efficiency and yield. Non-tillage management did not significantly reduce soil bulk density compared to conventional tillage, as no differences were observed between non-tillage and tillage systems throughout the 6-year experiment. There was no difference in total water-use efficiency among soil management practices in 2018, 2019, 2020, and 2021. Even though in one year of the study, a significant 24 kg ha-1 mm-1 improvement …


Development And Use Of A Detached Leaf Assay To Assess Soybean Cultivar Resistance To Target Spot, Caused By Corynespora Cassiicola, Rachael Wolf Aug 2023

Development And Use Of A Detached Leaf Assay To Assess Soybean Cultivar Resistance To Target Spot, Caused By Corynespora Cassiicola, Rachael Wolf

Graduate Theses and Dissertations

Target spot, caused by the fungus Corynespora cassiicola, was once considered a minor foliar disease of soybean in the US. However, a severe outbreak of target spot occurred in the southeastern U.S in 2016. Due to the lack of information on resistance in soybean cultivars, and the challenges in screening cultivars in the field, a detached leaf assay was developed to evaluate resistance. The objectives of the effort were to 1) develop a greenhouse inoculation method of soybean with C. cassiicola 2) use that method to compare reactions of soybean germplasm lines to target spot 3) collect and characterize isolates …


Time And Chance Happen To Them All: A Macroevolutionary Examination Of The Effects Of Whole Genome Multiplications, Eric Robert Hagen Aug 2023

Time And Chance Happen To Them All: A Macroevolutionary Examination Of The Effects Of Whole Genome Multiplications, Eric Robert Hagen

Graduate Theses and Dissertations

Polyploidy, the state of having more than two complete sets of chromosomes, is common in plants and has been linked to several beneficial traits. On the macroevolutionary scale, the effects of polyploidy have been hotly debated for over one hundred years, being alternatively described as an “evolutionary dead end” and the most important discovery in evolutionary biology since Darwin and Wallace. This thesis aims to contribute to the debate by studying the diversification, biogeography, and ecophysiology of polyploid flowering plants with recently developed phylogenetic comparative methods. This dissertation has three chapters. In Chapter I, I review work on the so-called …


Evaluation Of Drought Tolerance In Usda Tomato Germplasm And Genome-Wide Association Study And Genomic Prediction Of Fusarium Wilt Resistance In Common Bean Core Collection, Kenani Edward Chiwina Aug 2023

Evaluation Of Drought Tolerance In Usda Tomato Germplasm And Genome-Wide Association Study And Genomic Prediction Of Fusarium Wilt Resistance In Common Bean Core Collection, Kenani Edward Chiwina

Graduate Theses and Dissertations

Drought stress and Fusarium wilt disease present significant challenges to plant growth and agricultural productivity, particularly affecting crops such as tomato and common beans. To address these issues, researchers have extensively evaluated germplasm collections under field and greenhouse conditions to identify genotypes with drought tolerance and disease resistance. This study aimed to achieve two objectives. Firstly, we conducted a phenotypic evaluation of drought tolerance in USDA tomato germplasm to identify drought-tolerant accessions for future breeding programs targeting enhanced drought tolerance in tomato cultivars. Secondly, we conducted a genome-wide association study (GWAS) and genomic prediction (GP) on USDA common bean germplasm …


Phenotypic And Transcriptomic Characterization Of Rice Snrk1 Mutants Developed By Crispr/Cas9 Mutagenesis, Maria Clara Faria Chaves Aug 2023

Phenotypic And Transcriptomic Characterization Of Rice Snrk1 Mutants Developed By Crispr/Cas9 Mutagenesis, Maria Clara Faria Chaves

Graduate Theses and Dissertations

SnRK1 is a heterotrimeric protein kinase that is composed of a catalytic subunit (α) and two regulatory subunits (β and βγ), and it has a main role in regulating energy homeostasis in the plant by modulating anabolic and catabolic process. SnRK1 phosphorylates and alters the activities of enzymes involved in metabolism and regulates gene expression by altering the activity of chromatin-remodeling enzymes or the transcription factors. Rice contains three functional paralogs of SnRK1α: SnRK1αa (LOC_Os03g17980), SnRK1αb (LOC_Os08g37800), and SnRK1αc (LOC_Os05g45420). This study focused on the function of these SnRK1 paralogs by evaluating the phenotypic and transcriptomic characteristics and the disease …


Evaluation Of Biochar Rate And Hemp Cultivar For The Phytoremediation Of Heavy-Metal-Contaminated Soil From The Tar Creek Superfund Site, Dietrich Thurston Aug 2023

Evaluation Of Biochar Rate And Hemp Cultivar For The Phytoremediation Of Heavy-Metal-Contaminated Soil From The Tar Creek Superfund Site, Dietrich Thurston

Graduate Theses and Dissertations

Soil contamination by cadmium (Cd), lead (Pb), and zinc (Zn) at the Tar Creek Superfund site in Northeast Oklahoma remains a threat to the environment and local ecosystem. Phytoremediation by industrial hemp (Cannabis sativa L.) and the use of biochar (BC) have been independently shown to be effective methods to remediate heavy-metal-contaminated soils. The objective of this greenhouse study was to evaluate the effects of industrial hemp cultivar (‘Carmagnola’ and ‘Jinma’), BC rate (0, 2, 5, and 10% by volume), soil contamination level (low, medium, and high), and their interactions on above- and belowground (AG and BG, respectively) plant dry …


Electrochemically Precipitated Struvite Effects On Soil Property And Crop Response, Tatum Simms Aug 2023

Electrochemically Precipitated Struvite Effects On Soil Property And Crop Response, Tatum Simms

Graduate Theses and Dissertations

Phosphorus (P) is a vital resource that is finite and only mineable in raw-material form in a few countries worldwide. Struvite (MgNH4PO4·6H2O) is a mineral that can be produced from wastewater that may provide a promising alternative source of fertilizer-P for crop production, but comprehensive characterizations of struvite behavior in various soils and responses of various crops are necessary. This study aimed to determine the (1) leaching potential, (2) vertical soil profile-P distribution, (3) wheat (Triticum aestivum), corn (Zea mays), and soybean (Glycine max) response, and (4) soil property changes over time of electrochemically precipitated struvite (ECST) compared to that …


Screening A Set Of Tomato Genotypes For Resistance To Bacterial Wilt And A Genomic Wide Association Study And Genomic Prediction For Yield-Related Traits In ‘Lcp 85-384’. I. Sugarcane, Theresa Makawa Phiri Aug 2023

Screening A Set Of Tomato Genotypes For Resistance To Bacterial Wilt And A Genomic Wide Association Study And Genomic Prediction For Yield-Related Traits In ‘Lcp 85-384’. I. Sugarcane, Theresa Makawa Phiri

Graduate Theses and Dissertations

This thesis comprises two studies that focused on screening tomato genotypes for bacterial wilt resistance and a genome-wide association study and genomic prediction for yield-related traits in sugarcane with the aim of contributing to the breeding programs. In the first chapter, 40 tomato accessions from the USDA collection were evaluated for their resistance to Ralstonia solanacearum isolate P822 under controlled greenhouse conditions. The plants were inoculated, and disease symptoms were visually assessed. Disease severity was rated on a scale of 0 to 4, where 0 represented no wilting and 4 indicated complete leaf wilting. Among the tested accessions, five (PI …


An Investigation Of Seed Hardness And Seed Coat Color Values In Natto Soybean, Joshua Winter May 2023

An Investigation Of Seed Hardness And Seed Coat Color Values In Natto Soybean, Joshua Winter

Graduate Theses and Dissertations

Natto is a specialty fermented soyfood made from small-seeded (seeds-1) soybean varieties. Seed hardness and seed coat color are important seed traits that determine the texture and appearance of natto and are thus valuable to breeders. Prior research has identified quantitative trait loci (QTL, hereafter) for seed hardness, but its nature as a quantitative trait heavily influenced by the environment means that it is still poorly understood. Prior research has identified the primary genetic components of seed coat color using simple visual inspection, but few studies have investigated the usefulness of more quantitative measurements, such as the color space coordinates …


Multiomic Explorations Of Fruit Texture And Postharvest Quality In Blackberry And Muscadine Grape, Thomas Mason Chizk May 2023

Multiomic Explorations Of Fruit Texture And Postharvest Quality In Blackberry And Muscadine Grape, Thomas Mason Chizk

Graduate Theses and Dissertations

For most fresh-market fruit crops, texture is an important trait that strongly affects both shipping potential and consumer opinion. Efficient, scalable phenotyping methods are required by breeding programs to effectively select for improvements to fruit texture quality. In muscadine, we have developed a recommendation for characterizing complex muscadine grape texture profiles by comparing the results of breeders’ ratings, descriptive sensory panel results, and an array of instrumental protocols. Regression models were constructed to predict awareness of skins, crispness, hardness, and visual separation explaining 85%, 91%, 82%, and 83% of variance respectively. Genotypes that scored most highly in breeders’ ratings of …


Effect Of Nanobubble-Oxygenated Water For Irrigation Of Sand-Based Golf Course Putting Greens, Eric Deboer May 2023

Effect Of Nanobubble-Oxygenated Water For Irrigation Of Sand-Based Golf Course Putting Greens, Eric Deboer

Graduate Theses and Dissertations

Nanobubbles (NBs) are sub-micron, stable cavities of gas. The properties of NBs theoretically allow long bubble residence times and high gas dissolution rates resulting in the supersaturation of oxygen in water. Adequate soil aeration is a constant concern for producers of agricultural and horticultural crops. Because of their unique properties, NBs have been investigated for oxygenating water used in the irrigation of various agricultural and horticultural crops to increase soil oxygen concentration. Creeping bentgrass (Agrostis stolonifera L.) is the most widely used turfgrass for golf course putting green surfaces. Golf course superintendents use various methods to increase soil oxygen in …


Investigating Effect Of Seed Source And Developing Germination Protocols To Improve Success In Restoration Of Arkansas Tallgrass Prairies, Rhiannon Spencerosa May 2023

Investigating Effect Of Seed Source And Developing Germination Protocols To Improve Success In Restoration Of Arkansas Tallgrass Prairies, Rhiannon Spencerosa

Graduate Theses and Dissertations

American tallgrass prairie has faced losses estimated at 87-98% of original land area since European settlement. Native seeds are often used to supplement struggling or extinct plant populations in tallgrass prairie restoration and establishment sites. Two main considerations in restoration and establishment are from where to source seed and how to obtain high germination rates. In order to determine the effect of seed source, a common garden experiment was performed in Fayetteville, Arkansas in 2022 with five prairie species: Andropogon gerardii (big bluestem), Bouteloua curtipendula (sideoats grama), Panicum virgatum (switchgrass), Schizachyrium scoparium (little bluestem), and Sorghastrum nutans (Indiangrass). Seed was …


Dicamba Translocation And Metabolism In Susceptible Soybean And Evaluation Of Factors Contributing To Volatilization, Maria Leticia Zaccaro May 2023

Dicamba Translocation And Metabolism In Susceptible Soybean And Evaluation Of Factors Contributing To Volatilization, Maria Leticia Zaccaro

Graduate Theses and Dissertations

The expansion of dicamba-resistant technology increased the use of dicamba in season and relocated the off-target movement towards the growing season, negatively affecting susceptible vegetation, such as soybean. This research aimed to understand different aspects of the off-target movement of dicamba and impact on susceptible soybean. A study determined the accumulation of dicamba in soybean seed (grain) when parental plants at the pod-filling stage were treated with 1/200 of a labeled rate of dicamba at 560 g ae ha-1 and radiolabeled herbicide used as a tracer. This research found that 44% of the total herbicide absorbed by the parent plants …


Sustainability And Health Impacts Of Pulse Crops In The United States Using Life Cycle Assessment, Prathamesh A. Bandekar Dec 2022

Sustainability And Health Impacts Of Pulse Crops In The United States Using Life Cycle Assessment, Prathamesh A. Bandekar

Graduate Theses and Dissertations

Environmental sustainability and human health impact of pulses produced and consumed in the United States was assessed using life cycle assessment (LCA). The study included three objectives 1) to estimate environmental impact of current production and consumption practices in the United States using attributional LCA; 2) to estimate environmental and human health impact of iso-caloric diets containing varying amounts of pulses using Hybrid-LCA and Combined Nutritional and Environmental-LCA (CONE-LCA); and 3) to estimate environmental impact of increased demand for pulses using consequential LCA. Scope of the study varied for each objective with system boundary encompassing cradle-to-grave activities for objective 1 …


In-Field And Greenhouse Assessments Of A Selection Of Preemergent Herbicides On Newly Planted Blackberries, Kayla Knepp Dec 2022

In-Field And Greenhouse Assessments Of A Selection Of Preemergent Herbicides On Newly Planted Blackberries, Kayla Knepp

Graduate Theses and Dissertations

This field trial assesses some of the preemergence herbicide options available to growers and their effect on newly transplanted blackberries (Rubus L. subgenus Rubus Watson). Weed control has recently been surveyed as a top priority for blackberry growers; however, limited preemergence herbicides are registered for new blackberry plantings. Weed control is an ongoing component of blackberry production and with few in-season postemergence herbicide options available, growers rely on preemergence herbicides to maintain clean fields. The preemergent herbicides assessed in this trial were chosen with the intention to broaden the chemical control options available to growers in new plantings. A two-year …


Micronutrient Concentration Effects On Lettuce Growth And Susceptibility To Pythium, Kalyn M. Helms Dec 2022

Micronutrient Concentration Effects On Lettuce Growth And Susceptibility To Pythium, Kalyn M. Helms

Graduate Theses and Dissertations

In hydroponic production waterborne pathogens such as Pythium are ubiquitous and continually threaten a wide range of Controlled Environment Agriculture (CEA) crops in hydroponic production, including but not limited to: lettuce, spinach, basil, arugula, cucumber, tomato, sweet pepper, roses, chrysanthemums, and cannabis (Sutton et al., 2006; Gull, 2002; McGehee and Raudales, 2021; Gillespie, 2020). Despite extensive sanitation measures, disease control in hydroponics is fallible and requires constant surveillance and management to minimize outbreaks (Sutton et al., 2006). A potential disease suppression strategy is to increase micronutrient concentrations within hydroponic systems to naturally strengthen plant defenses against pathogens such as Pythium. …


Evaluation Of Biological And Chemical Seed Treatments For Management Of Rice Diseases, Sherif Adam Sharfadine Dec 2022

Evaluation Of Biological And Chemical Seed Treatments For Management Of Rice Diseases, Sherif Adam Sharfadine

Graduate Theses and Dissertations

Rice is the primary staple for more than half of the global population and is the second most important cereal worldwide. In the US, rice is primarily grown in the southern states, with Arkansas leading production and responsible for 47% of the total rice production in the country. Diseases cause significant yield losses in rice. Sheath blight, rice blast and bacterial panicle blight are the main diseases in rice and cause significant yield losses. Sheath blight alone could cause up 50% yield loss in heavily damaged fields with highly susceptible cultivars. Additionally, rice seed and seedling diseases primarily caused by …


Biology, Monitoring, Sampling, And Management Of Rice Billbug, Sphenophorus Pertinax, In Furrow-Irrigated Rice, Chase Alan Floyd Dec 2022

Biology, Monitoring, Sampling, And Management Of Rice Billbug, Sphenophorus Pertinax, In Furrow-Irrigated Rice, Chase Alan Floyd

Graduate Theses and Dissertations

Furrow-irrigated rice hectares have increased annually for the last five years in the predominant long-grain rice producing states. Initial implementation of the system began in the 1980’s, but lack of rice blast (Magnaporthe grisea, Hebert) resistant cultivars made the system a nonviable option for rice producers. Hybridization of rice cultivars with less susceptibility has begun to increase the interest of producers to implement a furrow-irrigated rice production system due to the cost saving opportunities that it may provide. Elimination of the flood from large sections of the rice fields in a furrow-irrigated system alters management strategies and pest complexes compared …


Nitrogen Use Efficiency Of Pretassel Nitrogen Applications In Corn, Robyn Brittlee Mulloy Dec 2022

Nitrogen Use Efficiency Of Pretassel Nitrogen Applications In Corn, Robyn Brittlee Mulloy

Graduate Theses and Dissertations

Corn (Zea mays L.) production continues to be a critical component of row-crop production systems within Arkansas and is seeing a resurgence in recent years. Nitrogen (N) is critical for corn growth and is often one of the single largest input costs associated with corn production. Research objectives for this study were to determine the nitrogen use efficiency (NUE) of late season N applications as influenced by sidedress N rate and timing of pretassel application and to quantify the nutrient uptake and partitioning in modern era corn hybrids within a furrow-irrigated production system. Research was conducted at the Milo J. …


Diagnosing Excess Nitrogen In Rice Using Post-Season Tissue Samples, Kyle Hoegenauer Dec 2022

Diagnosing Excess Nitrogen In Rice Using Post-Season Tissue Samples, Kyle Hoegenauer

Graduate Theses and Dissertations

Proper nitrogen (N) management in rice production can be difficult to achieve without the aid of tools such as soil and tissue tests. There are no tests currently available to rice producers that determine whether N has been managed properly throughout the season or that detect instances of over fertilization. Rice stalk samples were collected from N response trials within 3 days of harvest from the primary Arkansas rice growing region in 2016-2018. Stalk samples were analyzed for N concentration through a KCl extraction and spectrofluorometric quantification. Samples analyzed with leaf material intact contained statistically different N concentrations than samples …


Understanding The Potential Utility Of Tamarktm Grain Sorghum, Jacob Alan Fleming Dec 2022

Understanding The Potential Utility Of Tamarktm Grain Sorghum, Jacob Alan Fleming

Graduate Theses and Dissertations

Herbicide-resistant crops have been commonly used in corn, cotton, and soybean since the 1990s to control numerous different grass and broadleaf weeds. However, this technology has not been available for grain sorghum producers whom have faced challenges controlling grass weeds. Recently a collaboration between the University of Arkansas and Texas A&M University has resulted in a new bred line of grain sorghum, TamArkTM, which is resistant to ACCase inhibitor herbicides which have been previously used to control grass weeds in broadleaf crops. Multiple studies were conducted to determine the sensitivity of TamArkTM and problematic grass weeds to ACCase inhibitor herbicides, …


Applying A Material Science Approach To Improve Rice Processing Performance, Michelle Oppong Siaw Dec 2022

Applying A Material Science Approach To Improve Rice Processing Performance, Michelle Oppong Siaw

Graduate Theses and Dissertations

Rice is typically consumed as whole kernel, which makes the economic value of whole kernels twice that of brokens. Macro-structural defects such as fissures and chalkiness have been recognized to weaken kernel mechanical strength, and thereby increase breakage during milling. However, high percentages of brokens are sometimes recorded even though these defects are controlled prior to milling. It was hypothesized that rice milling characteristics are influenced by endosperm porosity from the structural arrangement of chemical components and by bran thickness and composition. Thus, this study aimed to modify chemical components by applying treatments to alter rice porosity and its associated …