Agronomy and Crop Sciences Commons^™

Generation And Evaluation Of Modified Opaque-2 (O2) Popcorn Suggests A Route To Quality Protein Popcorn (Qpp), Ying Ren

Department of Agronomy and Horticulture: Dissertations, Theses, and Student Research

I have been working on a Quality Protein Popcorn breeding project where QPM conversion is carried out simultaneously for several elite popcorn germplasms. During my study in the graduate program, I led the following aspects of the Quality Protein Popcorn Breeding Project:

1. Identified suitable QPMs as opaque-2 allele donors.

2.Examined the feasibility of quick introgression of the opaque-2 allele into popcorn lines via marker-assisted selection.

3. Monitored modification by SDS-PAGE zein profiling and light box phenotypic selection to make sure multiple modifier loci for opaque-2 were incorporated each time generation advancement was carried out.

4. Carried out high throughput …

Systems To Attract And Feed Pollinators In Warm-Season Lawns, Michelle Wisdom

Graduate Theses and Dissertations

Pollinating insects are responsible for the production of many agricultural crops and they require floral resources to fulfill their life-cycle. Ideally, pollinating insects will encounter a diversity of floral resources across their entire season of activity, and those floral resources can include both herbaceous and woody plant species. Managed turfgrass areas have been identified as potential locations for creating pollinator-friendly habitats. In the transition zone, where both warm- and cool-season turfgrass species are present, the persistence of herbaceous plants in warm-season turfgrasses such as bermudagrass (Cynodon spp.) and buffalograss (Buchloe dactyloides), may be affected not only by the competitive nature …

Arkansas Corn And Grain Sorghum Performance Tests 2018, R. D. Bond, J. A. Still, J. F. Carlin

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.

Physiological Characterization Of The Soynam Parental Lines Under Field Conditions, Akshita Mishra

Graduate Theses and Dissertations

The narrow genetic pool of soybean (Glycine max L. Merr.) in North America can limit its future yield gains. Among the worldwide germplasm collection of 45,000 unique landraces, only 80 contribute 99% to the collective parentage of North American soybean cultivars. Among these 80 landraces, just 17 contribute to 86% of the collective parentage of the modern cultivars. The Soybean Nested Association Mapping population (SoyNAM) was therefore developed with the objective of diversifying the soybean gene pool. Forty diverse soybean genotypes from maturity groups (MG) 1 through 5 were crossed with a common MG 3 parent to develop 40 recombinant …

A Simple Metabolic Switch May Activate Apomixis In Arabidopsis Thaliana, David Alan Sherwood

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Apomixis, asexual or clonal seed production in plants, can decrease the cost of producing hybrid seed and enable currently open pollinated crops to be converted to more vigorous and higher yielding hybrids that can reproduce themselves through their own seed. Sexual reproduction may be triggered by a programmed stress signaling event that occurs in both the meiocyte, just prior to meiosis, and later in the egg just prior to embryo sac maturation. The prevention of stress signaling and the activation of a pro-growth signal prior to meiosis triggered apomeiosis, the first half of apomixis. The same approach was used prior …

Weed Control And Management For Vegetable Soybeans In Arkansas, Seth Bernard Abugho

Graduate Theses and Dissertations

Vegetable soybean [Glycine max (L.) Merr.], known as edamame, needs weed management tools. Releasing locally adapted edamame soybean varieties and registering herbicides are necessary for successful production and expanding the edamame industry. This research aimed to 1) identify herbicides labeled for grain soybean for potential use on edamame; 2) evaluate differential tolerance of edamame soybean varieties to selected grain soybean herbicides; and 3) identify a feasible edamame-based crop rotation system. For objective 1, 26 herbicide treatments were tested on AVS-4002 edamame including preplant (PPL), preemergence (PRE) and postemergence (POST) herbicides labeled for grain soybean. Preplant herbicides caused 9 to 28% …

Evaluation Of Rice Stink Bug, Oebalus Pugnax (F.), Damage And Monitoring Techniques In Rice, Oryza Sativa L., And Grain Sorghum, Sorghum Bicolor (L.), Aaron Joseph Cato

Graduate Theses and Dissertations

Rice stink bug, Oebalus pugnax (F.), is a serious pest of headed rice, Oryza sativa L. and an occasional pest of heading grain sorghum in the Mid-south. Work from this dissertation focuses on resolving gaps in and knowledge of rice stink bug sampling and management, and attempts to create a basis for rice stink bug damage assessment in future studies.

Field experiments were conducted from 2016-2018 to asses variation in sweep net sampling by observing producers, researchers, extension personnel, consultants and their workers. Large levels of variation were found in sweep lengths between observed sweepers and reliability of smaller sweep …

Evaluation And Characterization Of Fitness Costs In Multiple Herbicide Resistant Echinochloa In Arkansas, Teal Marie Penka

Graduate Theses and Dissertations

Echinochloa spp. are major weed problems for rice (Oryza sativa L.) on a global scale. In the southern rice belt of the U.S.A., Echinochloa colona (L.) Link (junglerice) and E. crus-galli (L.) P. Beauv (barnyardgrass) are the most troublesome weeds. These species are morphologically diverse, and its high ploidy level augurs high genetic diversity, which favors high adaptability to stress, including herbicide selection pressure. The objectives of these studies were to 1) isolate resistant (R) and sensitive (S) biotypes from eight accessions of E. colona with different resistance profiles; 2) determine the resistance levels of selected R and S biotypes …

Evaluation Of Soybean Maturity Group And Planting Date In A Soybean-Rice Rotation On Overall Crop Productivity, Carrie Ortel

Graduate Theses and Dissertations

Little is known about the effects of soybean (Glycine max L.) management techniques on soil-nitrogen (N) credit development and its impact on the subsequent rice (Oryza sativa L.) crop’s success. This study was conducted to determine how soybean maturity group (MG) and planting date effect overall soybean productivity and its influence on the following rice crop. Various soybean planting dates (optimum and late) and MGs (3.5, 4.7, 5.4, and 5.6) were grown and followed in rotation with a rice crop. Six rates of pre-flood fertilizer-N (0, 44, 89, 134, 179, 224 kg N ha-1) were applied to the rice crop. …

Soybean Androgenesis, Martina Garda

Student Theses and Dissertations

Food is a constant world demand, and soybeans are among the most complete food crops which have fed people since its domestication. Unfortunately, soybean is a difficult crop to work within the biotechnology laboratory. Soybean androgenesis has been a challenging process yet to be advanced significantly after years of attempts. There have been some minor advances, for instance, reports of a 2% induction rate in anther culture, formation of roots, rare shoots, but only a handful of plantlets that did not survive to maturity. This dissertation compiles these efforts in the context of developing a pyramidal stressors model for androgenesis …

Soil Responses To One-Season Winter Cover Crops, Mckenna Morgan, Iin Handayani

Posters-at-the-Capitol

Soil Responses to One-Season Winter Cover Crops

McKenna Morgan and I. P. Handayani

Hutson School of Agriculture Murray State University, KY, USA

Abstract

In regions like western Kentucky where wooded lots are common there is a growing interest in how to utilize them so that land profits can be maximized. The frequently poor soils in wooded areas due to erosion and lack of ground cover vegetation often cause complications in the creation of pasture areas. Therefore, the objective of this study was to assess the effect of growing winter cover crops on soils to prepare for pasture systems in the …

Hybridisation-Based Target Enrichment Of Phenology Genes To Dissect The Genetic Basis Of Yield And Adaptation In Barley, Camilla Beate Hill, Tefera Angessa, Lee-Anne Mcfawn, Debbie Wong, Josquin Tibbits, Xiao-Qi Zhang, Kerrie Forrest, David Moody, Paul Telfer, Sharon Westcott, Dean A. Diepeveen, Yanhao Xu, Cong Tan, Matthew Hayden, Chengdao Li

Grain and Other Field Crops Research Articles

Barley (Hordeum vulgare L.) is a major cereal grain widely used for livestock feed, brewing malts and human food. Grain yield is the most important breeding target for genetic improvement and largely depends on optimal timing of flowering. Little is known about the allelic diversity of genes that underlie flowering time in domesticated barley, the genetic changes that have occurred during breeding, and their impact on yield and adaptation. Here, we report a comprehensive genomic assessment of a worldwide collection of 895 barley accessions based on the targeted resequencing of phenology genes. A versatile target-capture method was used to …

Modeling Effects Of Ecological Factors On Evolution Of Polygenic Pesticide Resistance, C. V. Haridas, Brigitte Tenhumberg

School of Biological Sciences: Faculty Publications

Widespread use of pesticides has resulted in the evolution of resistance in many insect pests worldwide, limiting their use in pest control. Effective pest and resistance management practices require understanding of the genetics of resistance and the life history of the pest. Most models for pesticide resistance assume that resistance is monogenic, conferred by a single gene. However, resistance could evolve as a polygenic quantitative trait resulting from the action of several genes, especially when pesticide dose is low. Further, fitness of the pest could be density dependent and might depend upon abiotic factors such as temperature. It is not …

Investigation Of Alternative Hosts And Agronomic Factors Affecting Xanthomonas Vasicola Pv. Vasculorum, Causal Agent Of Bacterial Leaf Streak Of Corn, Terra Marie Hartman

Department of Agronomy and Horticulture: Dissertations, Theses, and Student Research

Xanthomonas vasicola pv. vasculorum, causal agent of bacterial leaf streak of corn, was first reported in the U.S. in 2016 on Nebraska corn leaf samples. Prior to this report, the pathogen had only been reported on corn in South Africa. After the Nebraska report, the pathogen was reported on corn in Argentina, Brazil, and several U.S. states. This pathogen has an extensive host range, which includes sugarcane (Saccharum officinarum), grain sorghum (Sorghum bicolor), palm species (Dictyosperma album, Roystonea regia, and Areca catechu) and broom bamboo (Thysanolaena maxima). Plants commonly found in …

Biological Activity Of A Tertiary Amine Plant Growth Regulator, Bmve, In Arabidopsis Thaliana And Wheat (Triticum Aestivum), Jaspinder Singh

Department of Agronomy and Horticulture: Dissertations, Theses, and Student Research

Plant growth regulators are synthetic compounds that influence plant growth and development and can increase growth, yield, and nutritive value of food crops. Research in the past has shown that a class of plant growth regulators known collectively as substituted tertiary amines have the potential to increase crop productivity, photosynthetic efficiency, and overall plant vigor. However, earlier efficacy studies that involved spraying plants were sometimes inconsistent or showed only minimal benefits. A new delivery method involving seed application of tertiary amines before sowing has shown promise in field trials for multiple crop species (US patent 9464283) (Yokoyama, Chan, Oyama, & …

Identification Of Genes/Genomic Regions Controlling Resistance To Biotic And Abiotic Stresses In Synthetic Hexaploid Wheat, Madhav Bhatta

Department of Agronomy and Horticulture: Dissertations, Theses, and Student Research

Synthetic hexaploid wheat (SHW; 2n=6x=42, AABBDD, Triticum aestivumL.) is produced from an interspecific cross between durum wheat (2n=4x=28, AABB, T. turgidumL.) and goat grass (2n=2x=14, DD, AegilopstauschiiCoss.). It is reported to have a considerable amount of genetic diversity and is a potential source of novel alleles controlling abiotic and biotic stresses resistance and improving wheat quality. Therefore, the first study was to understand the genetic diversity and population structure of SHWs and compare the genetic diversity of SHWs with elite bread wheat (BW) cultivars. The result of this study identified a wide range of genetic diversity within …

Canavalia Gladiata And Dolichos Lablab Extracts For Sustainable Pest Biocontrol And Plant Nutrition Improvement In El Salvador, Carlos Martinez

Department of Agronomy and Horticulture: Dissertations, Theses, and Student Research

Botanical repellents and pesticides are now being rediscovered as new tools for integrated pest management in order to reduce the use of toxic chemicals in crop production. Canavalia gladiata and Dolichos lablab are two Fabaceae very well adapted to farmlands of El Salvador, effective as living barriers and mostly as cover crops, however, they are not yet very well disseminated. This document describes the potential for using the liquid extracts and the dry flour of raw seeds of those plants for economic benefit and practical convenience for pest management in Salvadorian agriculture under field conditions. Seed extracts were useful when …

Assessment Of Soil Fertility Under Different Land-Use Systems In Dhading District Of Nepal, Sudarshan Kharal, Babu Ram Khanal, Dinesh Panday

Department of Agronomy and Horticulture: Faculty Publications

Unscientific land use and cropping techniques have led high soil erosion and degradation of soil quality in the mid-hills of Nepal. To understand the effects of land use systems for selected soil chemical properties in mid-hills, composite soil samples at 0 cm to 20 cm depth were collected from five different land-use systems: Grassland, forest land, upland, lowland, and vegetable farms from Dhading district of Nepal in 2017. Soil samples were analyzed for soil fertility parameters: Soil pH, organic matter (OM), total nitrogen (N), available phosphorus (P), available potassium (K) and its effect due to different land use systems were …

Research Report: Prevalence And Mechanism Of Atrazine Resistance In Waterhemp From Nebraska, Rodrigo Werle, Mithila Jugulam, Greg Kruger, Amaranatha Vennapusa, Felipe Faleco, Bruno Viera, Spencer Samuelson

Department of Agronomy and Horticulture: Faculty Publications

Waterhemp is a troublesome summer annual broadleaf weed species that has evolved resistance to glyphosate and other herbicide sites of action (SOA) in Nebraska, including to groups 2 (i.e., Classic, Pursuit, FirstRate), 4 (i.e., 2, 4-D), 5(i.e., atrazine) and 27 (e.g., Callisto, Laudis). The overall objectives of this study were to

1. Evaluate the eficay of PRE applied atrazine, metribuzin and sulfentrazone to control Nebraska waterhemp populations;
2. Evaluate the efficacy of POST applied atrazine to control Nebraska waterhemp populations; and
3. Determine the mechanism of atrazine resistance in Nebraska waterhemp populations.

Digital Soil Mapping In The Bara District Of Nepal Using Kriging Tool In Arcgis, Dinesh Panday, Bijesh Maharjan, Devraj Chalise, Ram Kumar Shrestha, Bikesh Twanabasu

Department of Agronomy and Horticulture: Faculty Publications

Digital soil mapping has been widely used to develop statistical models of the relationships between environmental variables and soil attributes. This study aimed at determining and mapping the spatial distribution of the variability in soil chemical properties of the agricultural floodplain lands of the Bara district in Nepal. The study was carried out in 23 Village Development Committees with 12,516 ha total area, in the southern part of the Bara district. A total of 109 surface soil samples (0 to 15 cm depth) were collected and analyzed for pH, organic matter (OM), nitrogen (N), phosphorus (P, expressed as P_{2 …}