Life Sciences Commons^™

Development Of Genomic Resources And Group Specific Markers For Evaluation Of Genetic Diversity Of Pathogenic Rhizoctonia Species, Juanita Gil Bedoya

Graduate Theses and Dissertations

Rhizoctonia is a complex genus in the phylum Basidiomycota comprised of several taxa distributed across different families in the order Cantharellales. Many species in the genus have been identified as plant pathogens, saprobes, or beneficial mycorrhizal symbionts of orchids. Rhizoctonia isolates are divided into binucleate and multinucleate and then classified into anastomosis groups (AGs) based on the ability of compatible hyphae to fuse. Binucleate Rhizoctonia species (Ceratobasidium spp.) are classified into 21 AGs identified with letters (AG-A to AG-U). Multinucleate Rhizoctonia species (Thanatephorus spp.) are identified with numbers and classified into 14 anastomosis groups (AG-1 to AG-13, and bridging group …

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 …

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 …

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 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 …

Social Media Impacts On Arkansas Consumer Perceptions Of Gmos, Elizabeth R. Berner

Graduate Theses and Dissertations

This study builds upon previous consumer perceptions of GMOs studies. A need existed to determine what, if any, effects social media messages about GMOs had on consumer perceptions in Arkansas. The study utilized a qualitative approach with three focus groups. Data were analyzed using descriptive code. Participants were found to have a general understanding of GMOs, though discussion about what a GMO product was took an uncertain tone. Most participants did not consider GMOs as a factor when purchasing products. Rather participants considered characteristics such as price, quality, and convenience. Participants did not believe the infographics had changed their opinions …

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 …

Growing Agriculture Literacy’S Presence In America’S Classrooms, Emily Stone

Journal of Food Law & Policy

“Americans, as a whole, were at least two generations removed from the farm and did not understand even the most rudimentary of processes, challenges, and risks that farmers and the agricultural industry worked with and met head-on every day.” This quote perfectly describes the mindset of agriculture stakeholders in 1981 as they began to realize the drastic steps our education system had taken away from using principles of agriculture in K-12 education. As they saw it, Americans were moving out of rural America, away from farms, and becoming less connected to the food they daily consumed. Simultaneously, the education system …

The Contradictory Nature Of U.S. Laws And Nutrition Programs And Their Effects On Infant Feeding, Lily Patel

Journal of Food Law & Policy

The contradictory nature of U.S. laws, including the laws concerning infant feeding, though supposedly aligned with policies to promote wellness in Americans, can exacerbate gender and race inequality and work against the National Strategy. The overarching goal of U.S. laws concerning infant feeding is to ensure that infants are fed, nourished, and receive proper nutrition. However, the laws often appear to be directly contradictory to one another in the priorities they are promoting.

Utilizing The Genetic Potentials Of Traditional Rice Varieties And Conserving Rice Biodiversity With System Of Rice Intensification Management, Yheni Dwiningsih

Crop, Soil and Environmental Sciences Faculty Publications and Presentations

The genetic potentials of rice cultivars will need to be expressed to their fullest if global rice production is to be expanded enough by 2050 to meet the increased demand of the expanding population while the availability of land and water per capita dwindles. New and ‘improved’ rice varieties have contributed greatly to increased production over the past 50 years, but the rate of rice yield increase based on genetic changes has declined in recent decades compared with the early years of the Green Revolution. In fact, many rice consumers continue to prefer to consume ‘traditional’ rice varieties (referred to …

Effects Of Seasonal Environment On Abundance, Behavior, Visual Signaling, And Perception In Prairie Butterflies, Grace Elizabeth Hirzel

Graduate Theses and Dissertations

Phenotypic plasticity is a widespread mechanism that allows animals to respond quickly to seasonal changes in their environment. However, the depth and complexity of these plastic responses is still being discovered. One aspect of seasonal physiology that is relatively unstudied is changes to sensory physiology and how it may explain changes in behavior. To determine how changes in seasonal conditions affect behavior, coloration, and vision, I examined populations of wild butterflies in Northwest Arkansas. Focusing on a single species, the common buckeye Junonia coenia, I found that seasonal coloration covaries with thermoregulating behavior and is accompanied by changes in visual …

Demographics, Sexual Dimorphism, And Ecological Aspects Of Ambystoma Annulatum (Ringed Salamander) In Northwest Arkansas, Usa, Brian M. Becker

Graduate Theses and Dissertations

The need to study and monitor amphibian populations is increasing along with the threats to their population stability and persistence in nature. Northwest Arkansas is one of the fastest growing areas in the nation and with that growth comes rapid changes in land use, massive alterations to habitats, habitat loss, and the introduction of nonnative plants and animals. Ambystoma annulatum (Ringed Salamander) is an Ambystomatid endemic to the Ozark and Ouachita Mountains of southern Missouri, northern and western Arkansas, and eastern Oklahoma giving it a relatively small distribution compared to most Ambystoma. Therefore, Arkansas constitutes a significant portion of the …

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 …

Overexpression Of Acetyl Coa Carboxylase 1 And 3 (Accase1 And Accase3), And Cyp81a21 Were Related To Cyhalofop Resistance In A Barnyardgrass Accession From Arkansas, Fidel Gonzalez-Torralva, Jason K. Norsworthy

Crop, Soil and Environmental Sciences Faculty Publications and Presentations

Barnyardgrass [Echinochloa crus-galli (L.) P. Beauv.] is the most difficult-to-control weed species of rice production systems worldwide. It has evolved resistance to different herbicide sites of action, including the acetyl-CoA carboxylase (ACCase)-inhibiting herbicides. Target-site mutations conferring resistance to ACCase-inhibiting herbicides are well documented; however, the role of the different ACCase genes in conferring resistance to cyhalofop-p-butyl (cyhalofop), an ACCase-inhibiting herbicide, remains poorly understood. This research assessed the contribution of gene amplification and expression of ACCase genes in a cyhalofop-resistant barnyardgrass accession. Additionally, the expression of glutathione-S-transferases (GSTs) and cytochrome P450 monooxygenases (P450s) genes as possible …

Amyloid Fibrils Of Human Fgf-1 Induced By Different Detergents, Zeina Ismael Ibrahem Alraawi

Graduate Theses and Dissertations

Nature achieves molecular self-assembly through the ordered growth of nanoscale building blocks with high efficiency to fabricate macromolecular architectures. One example of self- assembly is peptides folding onto protein is one of the most astounding biological self-assembly processes. When proteins aggregate to form amyloid fibers, the secondary structure of the protein converts from its native state to a cross-beta-sheet. Fibroblast growth factors (FGFs) possess an essential role in neuronal survival during development. In addition, they are involved in neural stem cell (NSC) proliferation. Fibroblast growth factors (FGFs) are well known to be synthesized in the central nervous system (CNS) and …

Nutritional-Environmental Trade-Offs In Potato Storage And Processing For A Sustainable Healthy Diet, Aubin Payne, Ebenezer M. Kwofie, Prince Agyemang, Jamie Baum

Biological and Agricultural Engineering Faculty Publications and Presentations

Over the last decade, poor diets and limited access to nutritious foods have been critical drivers of micronutrient deficiency in human health. However, food fortification at an industrialized scale in developed countries has helped eliminate deficiency-related diseases. In developing countries, fortified foods and biofortified materials have been delivered to nutrient-deficient communities. While these strategies have produced significant and acclaimed results, reports from the Food and Agricultural Organization suggest that over a quarter of the world’s population suffers from micronutrient deficiency. This implies that there are still declines in micronutrients in food products at different nodes along the food value chain …

Winter-Time Cover Crop Identification: A Remote Sensing-Based Methodological Framework For New And Rapid Data Generation, Zobaer Ahmed, Lawton L. Nalley, Kristofor R. Brye, V. Steven Green, Michael P. Popp, Aaron Michael Shew, Lawson Connor

Environmental Dynamics Faculty Publications and Presentations

Accurately identifying and systematically mapping winter-time cover crops and their phenological characteristics offer significant benefits to agricultural producers and policymakers, as cover crops are one of several potential solutions to climate change mitigation. We present a methodological framework for identifying and mapping the presence of winter-time cover crops at the field level and aggregated to county scales from 2013 to 2019 by using the Google Earth Engine (GEE), a random forest classifier with time series data from Landsat 8, and yearly cover crop training data from the United States Department of Agriculture (USDA)-Natural Resources Conservation Service (NRCS). The methodology was …

Exploring The Potential Of Tesla Valve For Filtering And Sorting Microscale Active Swimmers: A Computational Study, Ariel Rogers, Zhiyao He, Yong Wang

Physics Faculty Publications and Presentations

It is well-known that a Tesla valve allows fluids to flow unidirectionally without moving parts; however, how Tesla valves interact with active matters and the potential applications of Tesla valves in biology remain largely unexplored. Here, we present a computational study on the potential use of Tesla valves for filtering and sorting microscale active swimmers such as bacteria. We investigated the behavior of microscale swimmers passing through the Tesla valve at different linear and angular velocities using numerical simulations and quantified the diodicity of the Tesla valve for active swimmers. Our results demonstrate that the Tesla valve can effectively filter …

A Muscle Exercise Research Revolution Powered By -Omics At Single Cell And Nucleus Resolution, Kevin A. Murach, Charlotte Peterson

Health, Human Performance and Recreation Faculty Publications and Presentations

In the last few years, single cell and single nucleus RNA-sequencing technologies have been leveraged in exercised adult skeletal muscle to reveal complex cell type-specific regulation of muscle plasticity. Expanding -omics technology at single cell resolution, complimented by advanced computational approaches, promise to rapidly accelerate our understanding of how exercise confers its numerous beneficial effects, paving the way for cell type-specific and targeted therapeutics to increase exercise responses during aging and in the face of chronic disease.

Arkansas Soybean Research Studies 2022, Jeremy Ross

Arkansas Agricultural Experiment Station Research Series

Arkansas is the leading soybean-producing state in the mid-southern United States. Arkansas ranked 11th in soybean production in 2022 when compared to the other soybean-producing states in the U.S. The state represented 3.04% of the total U.S. soybean production and 3.64% of the total acres planted in soybean in 2022. The 2022 state soybean average yield was 52.0 bushels per acre, tying the previous state yield record of 52 bushels per acre set in 2021. The top five soybean-producing counties in 2022 were Mississippi, Crittenden, Phillips, Poinsett, and Arkansas (Table 1). These five counties accounted for over 35.7% of the …

Adoption And Continued Use Of Irrigation Management Practices In Arkansas, Evelyn Osei

Graduate Theses and Dissertations

The paper assesses row crop producers continued use of irrigation management practices, namely the decision to continue rather than stop the use of irrigation practices, using a probit with a sample selection model. To better explain and increase user acceptance, we must understand why producers adopt and continue using irrigation management practices. Past studies have researched the adoption of management practices. However, it is also essential to consider what factors influence continued use and why producers discontinue irrigation practices after adoption. This is the first study to investigate factors influencing the continued use of irrigation management practices in Arkansas. Producers …

Economic Analysis Of Sod-Seeded Summer Annuals For Forage And Grazing, Ivanelle Meyer

Graduate Theses and Dissertations

Forage and pasture trials were conducted over the summers of 2021 and 2022 to assess how forage production and nutritive value of sorghum sudangrass, cowpea, and sorghum sudangrass-cowpea mixtures, sod-seeded to bermudagrass pasture would impact stocker cattle performance. The forage trials compared forage production and quality when poultry litter was surface or sub-surface applied biennially in comparison to a no poultry litter control. Poultry litter is a nutrient dense fertilizer utilized on pastures in the mid-southern United States to increase forage nutritive value and yield. Broadcasting poultry litter results in more nutrient losses due to runoff and nitrogen volatilization compared …

Understanding The Kinetics Of Laser-Induced Nanowelding Of Nanoparticles And The Motility Of Bacteria When Faced With Obstacles, Ariel Rogers

Graduate Theses and Dissertations

This dissertation has two focus areas: nanoparticle nanowelding and bacteria motility in the presence of micrometer sized structures. There are two main projects for the nanoparticle nanowelding studies: “Real-time imaging of laser-induced nanowelding in solution” and “Two-color laser-induced nanostructure shape modulation.” For the real-time imaging project, I used a fluorescence microscope, a 405 nm laser, and various python packages to quantify the average size of nanowelded nanostructures as a function of time and found that the average nanostructure growth over time fit the parameters of A¯(t) ∝ c0(1−e−t/τ), where c0 represents the initial concentration of nanoparticles in the solution and …

Economic Analysis Of Solar Investment In An Agricultural Setting, Morgan King

Graduate Theses and Dissertations

Robust financial modelling is critical for evaluating solar investments in agricultural applications. Agricultural producers with electricity-intensive systems (especially poultry houses but also, for example, irrigation pumps) face monthly electricity bills in the thousands of dollars. Further, volatile electricity bills, because of uncertain electric rate inflation, add to financial risk as utility costs make up a large portion of operating costs. While solar panels reduce input cost risk with certain installation cost up front, producers are hesitant to invest given long payback periods, uncertainty about the future of net metering, and high financial leverage. To enable producers to accurately assess the …

Corn And Grain Sorghum Performance Tests 2023, J. F. Carlin, R. B. Mulloy, R. D. Bond, J. C. Mccoy

Arkansas Agricultural Experiment Station Research Series

Corn and grain sorghum performance tests are conducted each year in Arkansas by the University of Arkansas System Division of Agriculture. The tests provide information to companies marketing seed within the state and aid the Arkansas Cooperative Extension Service in formulating recommendations for producers.

The 2023 corn performance tests contained 46 hybrids and were conducted at the Northeast Rice Research and Extension Center (NERREC) at Harrisburg, the Northeast Rice Research and Extension Center (NEREC) at Keiser, the Lon Mann Cotton Research Station (LMCRS) near Marianna, the Rohwer Research Station (RRS) near Rohwer, and the Rice Research and Extension Center (RREC) …

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 …

Assessment Of Needs And Priorities For Precision Agriculture And Soil Testing In Arkansas, Solomon Frimpong

Graduate Theses and Dissertations

Optimum crop production is needed to meet the growing population's food, water, fiber, and energy needs. However, agricultural productivity is hampered by many destabilizing factors such as pest management challenges, declining water quantity, and climate change which threaten long-term food security. Maximizing productivity will require optimizing resources through Precision Agriculture (PA) by supplying inputs based on crop needs. Precision Agriculture offers tools that can be used to optimize crop management practices globally. However, stakeholders’ perceptions and the lack of data-driven site-specific recommendations limit stakeholders’ ability to fully harness the potential benefits of PA. Identification of stakeholder needs and approaches to …

A Cross-Sectional Study On The Impact Of The Covid-19 Pandemic On Sport-Related Concussion Clinical Presentation Within Adolescents And Adults, Emily Mcindoe

Graduate Theses and Dissertations

Introduction. The COVID-19 pandemic spanned across the globe in March 2020 and has since significantly impacted human life. There is evidence that supports symptom exacerbation and an increase in anxiety and depression in clinical presentation post-COVID-19 pandemic compared to pre-COVID-19 for multiple medical diagnoses. These medical diagnoses include migraines, post-traumatic stress disorder (PTSD), obsessive-compulsive disorder (OCD), and mild cognitive impairment. The effect that the pandemic had on the clinical presentation of sports-related concussions is understudied. It is possible that the COVID-19 pandemic has altered the clinical presentation of concussions as seen in other medical diagnoses. Given the increased reporting of …

Characterization Of Human Fibroblast Growth Factor 2 Variant To Determine Effects On Structure, Stability, And Cell Proliferation, Ryan Layes

Graduate Theses and Dissertations

Fibroblast growth factors (FGFs) are a family of cell signaling proteins conserved across multiple species. Each individual FGF elicits different cellular functions including, but not limited to, proliferation, migration, differentiation, angiogenesis, and wound healing. One of the most studied members, fibroblast growth factor 2 (FGF2), has demonstrated substantial wound healing capacity in a wide range of tissues including skeletal, muscular, neural, respiratory, epithelial, and cardiovascular. This ability makes FGF2 a potential therapeutic for a wide range of conditions and injuries. However, due to a short half-life at room temperature, therapeutic use of FGF2 is limited. It has been demonstrated that …

In Vitro And In Vivo Evaluation Of Antimicrobial Activity, Oocyst Sporulation Rate, Oocyst Integrity And Oocyst Infectivity In Eimeria Maxima M6 Oocyst Suspensions Treated With Chlorhexidine Salts In Comparison With Potassium Dichromate, Lauren Laverty

Graduate Theses and Dissertations

Eimeria species oocysts cause coccidiosis, one of the costliest diseases in the poultry industry. Coccidiosis infections cause significant economic losses due to reduced performance in chickens and turkeys. The objective of this thesis was to determine fecal bacterial recovery from chlorhexidine (CHX) salt suspensions containing Eimeria maxima M6 oocysts and evaluate the effect of CHX salts on oocysts during long-term cold storage. For bacterial recovery experiments, CHX digluconate and CHX gluconate were tested at different concentrations on poultry fecal slurries during oocyst shedding. Eimeria maxima M6 oocysts were evaluated in CHX salt suspensions to test the effect on oocyst degradation …