Agronomy and Crop Sciences Commons^™

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 …

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 …

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 …

Resistance To Herbicides Conferred By Amaranthus Palmeri Protoporphyrinogen Ix Oxidase Mutations, Pamela Carvalho De Lima

Graduate Theses and Dissertations

Palmer amaranth (Amaranthus palmeri S. Wats.) is one of the most problematic agronomic weeds to control in fields across Arkansas. Thus far, this species has evolved resistance to several herbicides, including protoporphyrinogen IX oxidase (PPO) inhibitors. The majority of PPO-resistant Palmer amaranth populations harbor a target-site mutation (substitution or deletion of amino acids). The objective of this thesis was to identify the level of fomesafen resistance conferred by PPO2 mutations from Palmer amaranth. The experiments conducted aimed to (1) characterize the level of resistance conferred by the transgene Palmer amaranth ppo2 carrying ΔG210 mutation into the wild type rice (Oryza …

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

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). …

Hu Aquaponics Monitoring And Control System : European Annual Edunet Conference 2020, Rachel L. Fogle, Glenn P. Williams, Josh R. Krug

Presidential Research Grants

The functional purpose of the HU Aquaponics Monitoring and Control System Project is to develop an environmental and plant monitoring and control system for the HU Aquaponics Lab, located in the Student Union. The project involves the design and implementation of technology that will regularly take measurements from the environment (e.g., air temperature, water temperature, pH, dissolved oxygen, etc). PLCnext Technology will systematically collect, store, and web-publish the measurement data for HU researchers and the public to use for scientific research.

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 …

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 …

Genetic Diversity: The Hub Of Plant Breeding, Foster Kangben

English Language Institute

Agriculture the world over is faced with the threat of food, fiber, and nutrition insecurity especially in the wake of climate change. However, employing two approaches to plant breeding, the molecular and phenotypic methods, can make use of genetic diversity in crop species in order to help surmount these challenges.

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.

Genetics Of Physiological Traits Associated With Drought Tolerance In Soybean (Glycine Max), Sumandeep Kaur Bazzer

Graduate Theses and Dissertations

Soybean (Glycine max L.) is one of the major row crops in the United States, and its production is often limited by drought stress. Physiological traits from exotic germplasm that confer drought tolerance may be useful in improving commercial soybean production. For example, carbon isotope ratio (δ13C) is positively correlated with water use efficiency (WUE), and nitrogen isotope ratio (δ15N) is negatively correlated with N2 fixation; canopy temperature (CT) is an indicator for genetic variation in transpiration and stomatal conductance. Therefore, the objectives of this research were to identify the genomic regions associated with: (1) δ13C and δ15N using a …

Developing A High-Throughput Method To Screen Soybean Germplasm For Hypoxia Tolerance In Hydroponic Systems, Derrick Harrison

Graduate Theses and Dissertations

Soybean [Glycine max (Merr.)], the second most planted crop in the United States, is sensitive to field flooding due to depletion of oxygen and accumulation of CO2 in the rhizosphere. There is a need to breed cultivars that are adapted to areas prone to flooding, but field evaluations in the U.S. are limited because of time (one generation per year) and availability of resources (impermeable soils, irrigation, equipment to build levees). The purpose of this study was to develop and execute a protocol of germplasm screening for hypoxia tolerance using hydroponics in a controlled greenhouse environment. Germination rates and vigor …

Phenotypic And Genotypic Studies In The Peach [Prunus Persica (L.) Batsch] And Muscadine Grape (Vitis Rotundifolia Michx.), Jennifer Anne Lewter

Graduate Theses and Dissertations

Peach: Peaches [Prunus persica (L.) Batsch] are routinely chilled to increase shelf-life. Exposure to temperatures of 5° C for two weeks can induce chilling injury (CI) symptoms, including flesh mealiness (or wooliness) and a lack of juiciness. Phenotypic data were collected on seven biparental F1 peach populations maintained at the University of Arkansas Fruit Research Station. A genome wide association study (GWAS) was performed using TASSEL 5 which identified four quantitative trait loci (QTLs) associated with expressible juice, four QTLs for mealiness, five QTLs for soluble solids, and three QTLs for fruit weight. Exploiting these genetic markers could help breeders …

Arkansas Corn And Grain Sorghum Research Studies 2019, Victor Ford, Jason Kelley, Nathan Mckinney Ii

Arkansas Agricultural Experiment Station Research Series

The 2020 Arkansas Corn and Grain Sorghum Research Studies Series is the inaugural edition of this annual report and includes research results on all topics pertaining to corn and grain sorghum production including disease management, environmental/sustainability, irrigation, post-harvest drying, soil fertility, weed control, and research verification program results. Our objective is capturing and broadly distributing 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 will also serve as a citable archive of research results. Research reports contained in this publication …

Determination Of Critical Y-Leaf Potassium Concentrations Across Reproductive Growth Stages For Direct-Seeded Delay-Flooded Rice, Chandler Edwin Gruener

Graduate Theses and Dissertations

Rice (Oryza sativa L.) grain yield can be limited by potassium (K) deficiency on soils low in exchangeable K. Visually diagnosing K deficiency during early reproductive growth is not easily done and the interpretation of traditional tissue analysis is limited to select growth-stages. Our primary focus was to define continuous critical Y-leaf-K concentrations during reproductive growth for the production of maximal grain yield. A secondary objective was to examine Y-leaf sap-K concentration, measured using a handheld device, as a rapid in-field method of monitoring rice plant K nutrition. The Y-leaf is defined as the uppermost fully extended leaf with a …

An Evaluation Of Unmanned Aircraft Systems' Ability To Assess Stripe Rust In Large Wheat Breeding Nursies, Jamison T. Murry

Graduate Theses and Dissertations

Stripe Rust (Puccinia striiformis f. sp. tritici) is a foliar disease that significantly impacts global wheat production, and resistant cultivars provide the most efficient method of control. High-throughput phenotyping using unmanned aircraft systems (UAS) offers a potentially more efficient method for field-based phenotyping compared to visual assessment. Here we tested the ability of remote sensing to predict stripe rust severity in a diverse population of 594 soft red winter wheat lines, planted in single-rows, and evaluated them by visually rating stripe rust intensity and remotely using the dark green color index (DGCI), normalized difference vegetation index (NDVI) and blue NDVI. …

Room To Grow: A Comparative Analysis Of Cannabis Regulation Models In Europe, Amanda H. Cronin

Independent Study Project (ISP) Collection

Debilitated by years of economic instability, the Spanish economy has not fully rebounded to its once strong place in the European market. And now, in the aftermath of a devastating pandemic, the nation will be searching for new sources of wealth. The lucrative market potential of controlled cannabis in medicinal and recreational settings is an attractive industry gaining popularity across Europe. This paper explores the various policy models and legal systems in Portugal, Germany, and the Netherlands. Combining a variety of sources, I seek to ascertain the best plan for Spain. Ultimately, analysis shows that a multi-pronged approach is the …

Arkansas Cotton Variety Test 2019, F. Bourland, A. Beach, E. Brown, C. Kennedy, L. Martin, B. Robertson

Arkansas Agricultural Experiment Station Research Series

The primary goal of the Arkansas Cotton Variety Test is to provide unbiased data regarding the agronomic performance of cotton varieties and advanced breeding lines in the major cotton-growing areas of Arkansas. This information helps seed companies establish marketing strategies and assists producers in choosing varieties to plant. These annual evaluations will then facilitate the inclusion of new, improved genetic material in Arkansas cotton production. Adaptation of varieties is determined by evaluating the lines at five University of Arkansas System Division of Agriculture research sites (Manila, Keiser, Judd Hill, Marianna, and Rohwer). Entries in the 2019 Arkansas Cotton Variety Test …

The Morphological, Physiological, And Genetic Underpinnings Of Intraspecific Salinity Tolerance In Sorghum Bicolor, Ashley N. Henderson

Graduate Theses, Dissertations, and Problem Reports

Decreases in land quality and quantity threaten the efficient production of agriculturally and economically pivotal crops. Such reductions in arable lands are a consequence of population growth and urbanization, and often result in the introduction of various abiotic stresses. The most common abiotic stressors include water limitation (drought), water logging (over watering), poor water quality (salinity), and extreme temperatures (cold, frost, heat). Each of these stressors negatively impact plant growth, development, and yield. Soil salinity, specifically, is a considerable constraint affecting lands used in agriculture. Salts in the soil rise both naturally and through anthropogenic factors making the abundance a …

Assembly Of Triticum Boeoticum Ssp. Aegilopoides And Triticum Monoccocum Genomes, Mustafa Aljadi

Electronic Theses and Dissertations

Wheat is ancient cereal. Wheat has n = 7 chromosomes which is belong to genus Triticum. The group Triticum monococcum sp. aegilopoides(boeoticum) is a diploid wheat (2n = 14). It has a morphology aspect of having narrow, flat spike which usually shatters before harvesting time. The domesticated type of T.boeoticum known as a diploid wheat of Triticum monococcum L. In this research we want to generate a high quality assembly of wild and domesticated type of Einkorn wheat. Our method is using Illumina short sequence reads assembled by both CLC, and W2RAP(Wheat/Whole- genome Robust Assembly Pipeline) software’s. In our approach …

Reverse Genetic Analysis Of Ehd1 For An Association Between Flowering Time And Seed Dormancy In Rice (Oryza Sativa L.), Yeter Karakoc

Electronic Theses and Dissertations

This research aimed to understand the evolutionary mechanism of seed dormancy and flowering time and to provide basic knowledge for the manipulation of germination features in crop breeding. Flowering time and seed dormancy are two adaptive traits for flowering plants. Seed dormancy (SD) helps regulate the timing of germination to promote the survival of seed-bearing plants in adverse environments. Cereal crops and weedy/wild relatives, such as Asian cultivated rice and weedy rice (Oryza sativa L.), have weak and strong seed dormancy, respectively. Thus, weedy and cultivated rice has been used as a model system to investigate mechanisms of seed dormancy …