Agronomy and Crop Sciences Commons^™

Resistance Screening And Association Mapping For Resistance To The Downy Mildew Pathogen Of Spinach, Dotun Olaoye

Graduate Theses and Dissertations

Spinach is an important cool leafy vegetable cultivated around the world, with large scale production in California and Arizona in the U.S. Spinach is a highly nutritious vegetable beneficial in the human diet. Spinach is affected by a number of biotic stressors. Downy mildew, caused by the oomycete pathogen Peronospora effusa, is a major threat to spinach as it affects the leaf quality and impacts the economic value of spinach. Several efforts have led to the development of resistant genotypes/cultivars to this pathogen. However, few studies have examined the genetics of resistance to the downy mildew pathogen in detail. This …

Does Integrating Crops With Livestock Production Impact Soil Properties And Crop Production?, Lindsey Anderson

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

Re-integrating crop and livestock production through cover crop (CC) and corn residue grazing could efficiently utilize resources and ensure profitability while improving environmental quality, but how this integration affects soils and crops is not well understood. We conducted two studies to address this. In the first study, we evaluated the impact of cattle (1.3-3.7 head ha^-1) grazing an oat (Avena sativa L.) CC on soil and crop yields in two adjacent irrigated no-till corn (Zea mays L.)-soybean (Glycine max L.) fields on silt loam soils in eastern Nebraska. Field I was grazed twice, while Field …

Production, Evaluation, And Selection Of Elite Quality Protein Popcorn (Qpp) Hybrids, Leandra Marshall Parsons

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

In 2017, twelve Quality Protein Popcorn (QPP) inbred lines were developed and selected as premier dent by popcorn crosses fit for hybridization and testing. These QPP inbred lines were derived from specific Quality Protein dent Maize (QPM) by ConAgra Brands® popcorn line crosses to produce high lysine, vitreous popcorn lines capable of near-equal popping characteristics compared to the original popcorn parents. The QPP hybridization project commenced in the summer of 2018 utilizing these 12 inbred QPP lines and crossing them in a full diallel. Since then, the production of QPP hybrids has employed a diverse set of selection factors evaluating …

The Effect Of Anionic Surfactants On Herbicide Mixtures And Solutions, Ely Daniel Anderson

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

Herbicide mixtures are popular for farmers to delay the evolution of herbicide-resistant biotypes from occurring and control existing herbicide-resistant weeds. Glufosinate is a contact herbicide that has been observed as a mixture partner with many herbicides. In many cases, antagonistic interactions have occurred when using glufosinate in mixture with other herbicides. The antagonistic interactions have resulted in applications with incomplete weed control. Adjuvants have been known to impact an herbicide application by increasing herbicide penetration, spreadability, and efficacy. Adjuvants added to glufosinate mixtures can impact spray applications and increase weed control. The objectives of this research were: (1) investigate the …

Estimating Irrigation In Rice Fields With A Water Balance Approach, Kristen Trinh

Biological and Agricultural Engineering Undergraduate Honors Theses

Global food production must increase to meet the demand associated with increased population growth, so irrigation water use will continue to rise. Therefore, it is important to monitor water usage particularly when an irrigation flowmeter is unavailable. A field water balance was created for a selection of rice fields in East-central Arkansas under observation in 2018 and 2019. From those, irrigation inputs are deduced from the water balance alone. First, each field had sensors that collected water table level (WTL) data. Next, other water inputs and outputs such as precipitation and evapotranspiration (ET) were collected from two modeled sources. The …

Industry Funding Scheme Regulations: A Review Of Operation And Effectiveness, May 2021, Department Of Primary Industries And Regional Development, Western Australia

Biosecurity published reports

Section 147 of the Biosecurity and Agriculture Management Act 2007 requires the Minister for Agriculture and Food to carry out a review of the operation and effectiveness of any regulations made for the purposes of establishing an Industry Funding Scheme (IFS) every five years.

In 2010, regulations establishing three IFSs commenced to address pest and disease threats relevant to Western Australia’s broadacre and pastoral cropping and livestock sectors. This report documents the second fifth-year anniversary statutory review of the following regulations:

• Biosecurity and Agriculture Management Industry Funding Scheme (Cattle) Regulations 2010

• Biosecurity and Agriculture Management Industry Funding Scheme …

Evaluation Of Irrigation And Nutrient Management Strategies In Rice Using Alternative Irrigation Methods, Justin Lee Chlapecka

Graduate Theses and Dissertations

As water resources gain value across the Mid-South, alternative irrigation strategies of rice (Oryza sativa L.) have garnered increasing attention. In 2015, an estimated 1.7% of Arkansas rice hectarage used alternate wetting and drying (AWD) irrigation and 0.9% used furrow irrigation. As of 2020, 2.5% used AWD and 16.9% used furrow irrigation, the latter accounting for near 99,000 ha in Arkansas. Little information exists in the scientific literature in relation to management of rice grown in the Mid-South without a conventional flood. This fact coupled with the rapid adoption rate, especially for furrow-irrigated rice (FIR), during the last five years …

Suppression Of Erecta Signaling Impacts Agronomic Performance Of Soybean (Glycine Max (L) Merril) In The Greenhouse, Yasmin Vasques Berchembrock, Flavia Barbosa Silva Botelho, Vibha Srivastava

Crop, Soil and Environmental Sciences Faculty Publications and Presentations

The ERECTA (ER) family of genes, encoding leucine-rich repeat receptor-like kinase (RLK), influences complex morphological and physiological aspects of plants. Modulation of ER signaling leads to abiotic stress tolerance in diverse plant species. However, whether the gain in stress tolerance is accompanied with desirable agronomic performance is not clearly known. In this study, soybean plants potentially suppressed in ER signaling were evaluated for the phenotypic performance and drought response in the greenhouse. These plants expressed a dominant-negative Arabidopsis thaliana ER (AtER) called ΔKinase to suppress ER signaling, which has previously been linked with the tolerance to water …

Mechanisms Of Overyielding And Coexistence In Diverse Tallgrass Prairie Communities, Leslie E. Forero

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Plants compete for the same basic nutrient and water resources. According to the competitive exclusion principle, when a substantial overlap in resource pools exists, the best competitor for resources should drive all other species to extinction. The ability for plants to coexist in violation of the competitive exclusion principle is the “biodiversity paradox”. Coexistence is actually beneficial for plants: as species diversity increases, you typically see increases in plant biomass production (known as the biodiversity-productivity relationship). The mechanisms behind coexistence and the biodiversity-productivity relationship remain an ecological mystery. One hypothesis is that plants obtain water and nutrients from different places …

Screening And Breeding Soybean For Flood Tolerance, Maria Roberta De Oliveira

Graduate Theses and Dissertations

Waterlogging can be detrimental to soybean [Glycine max (L.) Merr.] growth and development, with effects ranging from chlorosis and stunting to yield loss and plant death. Soybean responses to, and the effects of, waterlogging are dependent on the growth stage of the plant at the initiation of waterlogging. The objectives of this study were: (1) to assess the effectiveness of Genomic Selection (GS), Marker Assisted Selection (MAS) and Phenotypic Selection for flood tolerance at the progeny row stage as compared to random selection, for the development of high-yielding flood-tolerant lines; and (2) to compare field-screening and hydroponic greenhouse screening methodologies …

Quality Determinates Of Rice Price In Open Bag Markets In Sub-Saharan Africa, Bailey Peterson-Wilhelm

Graduate Theses and Dissertations

Weaknesses in the grades and standards system in low-income countries across Sub-Saharan Africa undermine the transparency of agricultural markets. In the Democratic Republic of the Congo (DRC), Ghana and Mozambique rice is predominately sold in open bags and if rice price does not reflect its quality, then inefficiencies may lead to consumer welfare losses. Importantly, it is possible that impoverished communities are priced out of the market due to inflated and inefficient prices. The objective of this study is to examine determinates of rice price by estimating the impact of selected rice quality attributes on rice prices in DRC, Ghana …

Crop Response To Low-Dose Dicamba, Mason Castner

Graduate Theses and Dissertations

The introduction of dicamba-resistant (DR) soybean [Glycine max (L.) Merr.] and cotton (Gossypium hirsutum L.) followed by a label allowing over-the-top applications of dicamba in the 2017 provided growers an additional option for broadleaf weed control. Because non-DR soybean is sensitive to low concentrations of dicamba, postemergence dicamba applications present growers choosing to plant non-DR soybean with concerns of damage from off-target movement through physical drift and volatilization of the herbicide as well as tank-contamination from prior dicamba application. Consequences of low-dose dicamba exposure on sensitive vegetative and reproductive soybean have been well researched, but little is known regarding the …

Starter Nitrogen Source And Preflood Nitrogen Rate Effects On Rice Grown On Clay Soils, Linda Rachelle Martin

Graduate Theses and Dissertations

Seedling rice (Oryza sativa L.) grown on clayey-textured soils generally develops slowly as compared to loamy-textured soils. Our research examined the effects of starter-N source and preflood-N rates on canopy closure, total aboveground N uptake, and grain yield of rice grown on clayey-textured soils. Eleven field trials were established in Arkansas and Mississippi including five trials with a hybrid cultivar and six trials using a pure-line cultivar. Starter-N sources included no starter-N (NONE), ammonium sulfate (AMS), diammonium phosphate (DAP), and urea (UREA) applied at 24 kg N ha-1 at the rice 2-leaf stage and five preflood-N rates ranging from 0-224 …

Short-Term Effects Of Winter Cover Crops On Soil Properties, Yield, And Partial Returns In A No-Tillage Soybean Rotation, Drew Dillon Kirkpatrick

Graduate Theses and Dissertations

Cover crops have the potential to provide many benefits including weed suppression, erosion control, and improvements to soil quality. These benefits can be affected by species, biomass accumulation, and management practices. Although large amounts of biomass are good for maximizing benefits, it can result in problems for establishing the subsequent crop. Soybean [Glycine max (L.) Merr.] accounts for over 50% of Arkansas crop hectares annually; therefore, understanding the effect that a cover crop can have on the following soybean crop is crucial to the successful implementation of cover crops within the state. A study was established to evaluate winter cover …

Transcriptional Activation Of Phytochrome-Interacting Factor 4 Is A Conserved Mechanism Of Thermomorphogenesis In Dicotyledenous Plants, Caroline Clutton

Honors Theses

In the model dicotyledonous plant Arabidopsis thaliana, the basic helix-loop-helix (bHLH) transcription factor Phytochrome-Interacting Factor 4 (AtPIF4) plays a central role in regulating the ambient temperature-regulated hypocotyl growth response. Warm temperatures induce AtPIF4 transcription and the accumulated AtPIF4 promotes thermomorphogenesis by enhancing the expression of a group of growth-related genes. However, whether this thermo-induced growth response is universal, and more importantly, whether there is a conserved thermomorphogenetic mechanism shared in dicots is largely unknown. Here we show that higher ambient temperatures promote the hypocotyl growth in four other dicotyledonous plants, including Brassica rapa, Camelina sativa, Nicotiana benthamiana …

The Flowering Dynamics And Seedset Of Cichorium Intybus L. Cv. Puna, Yongfeng Han, Chengbin Tang, Mouqiong

IGC Proceedings (1977-2023)

No abstract provided.

The Effects Of Time Of Application Of Nitrogen On Seed Yield, Efficiency Of N Fertilizer Use And Apparent N Fertilizer Recovery Of Russian Wildrye [Psathyrostachys Juncea (Fisch.) Nevski], Jianguo Han, Yunwen Wang, Shengquan Jiang, Bo Liu

IGC Proceedings (1977-2023)

No abstract provided.

Seed Yield Formation Of Festulolium And Lolium X Boucheanum Under Climatic Condition Of Latvia, Iveta Gutmane, Aleksandr Adamovich

IGC Proceedings (1977-2023)

No abstract provided.

Callus Induction And Plant Regeneration Of Poa Pratensis 'Nasu' Seeds Carried By China Recoverable Satellite Shijian‐8, Yinghua Guo, Lei Han, Guansheng Ju, Zhenyuan Sun

IGC Proceedings (1977-2023)

No abstract provided.

Tannin Contents Of Sainfoin (Onobrycyhis Viciifolia Scop) Grown With Or Without Irrigation And Harvested At Different Growth Stages, Y. Wang, T. A. Mcallister, S. N. Acharya, K. H. Ominski, D. O. Krause

IGC Proceedings (1977-2023)

No abstract provided.