Agriculture Commons^™

Genomic Selection Of Forage Agronomic Traits In Winter Wheat, Frank Maulana, Ki-Seung Kim, Joshua D. Anderson, Mark E. Sorrells, Twain J. Butler, Shuyu Liu, P. Stephen Baenziger, Patrick Byrne, Xue-Feng Ma

Department of Agronomy and Horticulture: Faculty Publications

Genomic selection (GS) can improve genetic gain of complex traits in plant breeding. Phenotyping agronomic traits of winter wheat (Triticum aestivum L.) for dualpurpose use is expensive and time-consuming. In this study, we compared the prediction accuracies of four GS models (RR-BLUP, GBLUP, GAUSS, and BL) for forage yield (FY), plant height (PH) and heading date (HD) of the hard winter wheat diversity panel (n = 298) using random and stratified sampling methods. In addition, we determined the appropriate training population (TP) size and marker density for GS of the traits. Moderate to high prediction accuracies ranging from 0.66 …

Corn And Soybean Response To Wastewater-Recycled Phosphorus Fertilizers, Shane Ylagan

Crop, Soil and Environmental Sciences Undergraduate Honors Theses

The ability to recycle phosphorus (P) from wastewaters could provide a sustainable, continuous source of P that might also help protect surface water quality from P enrichment. The mineral struvite (MgNH4PO4·6H2O) is an understudied material that can be created from Pcontaining wastewater and has been shown to have agricultural fertilizer value. The objective of this study was to evaluate the effects of electrochemically precipitated struvite (ECST), chemically precipitated struvite (Crystal Green; CG), diammonium phosphate (DAP), monoammonium phosphate (MAP), rock phosphate (RP), and triple super phosphate (TSP) on corn (Zea mays) and soybean (Glycine max) response in a 79-day greenhouse pot …

Can Small Farmers Survive?: Problems Of Commercializing The Milk Value Chain In Pakistan, Erum Sattar

Journal of Food Law & Policy

Milk in Pakistan is infused with the self-understanding of a nation. British colonial administrators laid the modern-day foundations of the country’s structure through land grants to small farmers. In an agricultural country where nearly forty percent of the population remains food insecure, rearing animals is a way of life in the rural areas where milk remains an important source of animal protein. Selling the daily surplus that families don’t consume is a significant source of earnings for cash poor families – and here an unprecedented change is taking place within dairy management and milk procurement systems. The scale of this …

A Snapshot Semester: Students’ Reflections Of Performance And Mental State Throughout A Graduate Course, Bradley D. Borges

Graduate Theses and Dissertations

Graduate students are anecdotally reputed to be among the most stressed groups of young adults. Common sources of stress for graduate students have included coursework, assistantships, finances, career preparation, and family (Wyatt & Oswalt, 2013; Mazzola, Walker, Shockley & Spector, 2011; Oswalt & Riddock, 2007). Guided reflection can be used by educators to assist students in both learning (Boud, Keogh & Walker, 2013; Kolb, 1984) and managing stress (Shoulders, Whitehead, & Morrison, 2018). By understanding how students’ progress through a semester in terms of both their learning and their management of stress, instructors and academic advisors can better anticipate times …

2020 Lambing Survey, Department Of Primary Industries And Regional Development, Western Australia

Animal production and livestock published reports

To better understand the impacts of poor and variable seasons on lambing and turnoff rates, the Department of Primary Industries and Regional Development (DPIRD) conducts special short surveys on lamb marking rates. The data collected in 2020 adds to survey results from 2018, 2017 and 2011 to build a comprehensive picture for WA.

Marking rate (number of lambs per ewe mated) is an important measure to determine the rate of renewal of the state flock, potential turnoff and rate of genetic gain. It also an indicator of the impact of our highly variable seasons.

Three-Lined Potato Beetle, Nick Volesky

All Current Publications

The three-lined potato beetle (Lema daturaphila) is part of the Chrysomelidae family of beetles. It originates from North and Central America but has since been reported causing economic damage to crops worldwide, such as the cape gooseberry in South Africa and potato in Australia. Though uncommon, the three-lined potato beetle has previously been documented in Utah. In August 2020, it was closely observed causing economic damage in tomatillo production on a commercial vegetable farm in rural Box Elder County, Utah. This fact sheet reviews three-lined potato beetle identification, life cycle, and look-alikes, damage, and management.

Row Covers, Nick Volesky, Katherine Wagner

All Current Publications

In agricultural use, a row cover is a transparent or semitransparent material that is used over crops (typically vegetables) for a variety of purposes. As an integrated pest management tool, row covers act as a physical barrier that prevents the movement of pests such as insects, birds, and mammals, to host plants. This form of management is popular in organic production to avoid chemical application. Row covers are also used to shield crops from environmental factors like cold or hot temperatures, and wind. Commonly used methods of application include floating row covers, hoop-supported row covers (also called low tunnels), and …

Assessment Of Grain Safety In Developing Nations, Jose R. Mendoza

Department of Food Science and Technology: Dissertations, Theses, and Student Research

Grains are the most widely consumed foods worldwide, with maize (Zea mays) being frequently consumed in developing countries where it feeds approximately 900 million people under the poverty line of 2 USD per day. While grain handling practices are acceptable in most developed nations, many developing nations still face challenges such as inadequate field management, drying, and storage. Faulty grain handling along with unavoidably humid climates result in recurrent fungal growth and spoilage, which compromises both the end-quality and safety of the harvest. This becomes particularly problematic where there is little awareness about health risks associated with poor …

Herding History: Law And The Transformation Of Collective Subjectivities In The Dairyspheres Of Ukraine, Monica Eppinger

Journal of Food Law & Policy

In response to the limitations of socialism and capitalism in meeting basic needs, this article explores the alternative version of modernity offered in post-Soviet Ukraine and its agriculture. Tracing a century of fundamental transformations through the story of milk, it finds a history that troubles universalized framings of indigeneity and colonialism. This article argues that under socialism milk became a product of collectivized effort and a reservoir of household resilience; and then, with post-Soviet disintegration of some forms of collective life and emergence of others, that milk has come to delineate spheres of both collective action and individual striving. This …

Discerning Competitive Vs. Facilitative Relationships Of Weeds On Forest Restoration Efforts At La Sal Del Rey, Tx, Mylen A. Arias

Theses and Dissertations

Dryland ecosystems need effective restoration strategies to address severe degradation. It is often assumed that voluntary forb weeds either compete with or have no effect on native seedlings. In contrast, theory and empirical work suggest a potential facilitative role for such forb weeds. We conducted a manipulative weed exclusion experiment at a semi-arid site in South Texas targeted for large scale forest restoration and subsequently dominated by early successional forb weeds to discern the net effect of these weeds on the growth and survival of target thornscrub tree and shrub seedlings. Overall, weed presence did not significantly affect seedling mortality …

Women In Beekeeping: Impacts Of A Beekeeper Educational Program, Bridget Gross

Department of Entomology: Dissertations, Theses, and Student Research

The decline in honey bee populations over the past two decades in the United States is alarming. The management provided by beekeepers to their honey bee colonies influences the survival of the colony. However, there is a lack of information on the experiences of beekeepers, specifically women beekeepers. The Center for Rural Affairs (CFRA) in Nebraska hosted the “Honey Bees on the Farm: Connecting Women Beekeepers and Women Farmers for Environmental and Economic Benefit” program that provided informal, educational events to women beekeepers and landowners. Using a convergent mixed methods design, the first research question examines the impacts of the …

The Uniform Soybean Tests: Northern Region 2020, Guohong Cai, Adam Brock

Uniform Soybean Tests Northern Region

The purpose of The Uniform Soybean Tests is to critically evaluate the best of the experimental soybean lines developed by federal and state research personnel in the U.S. and Canada, for their potential release as new varieties. A test is established for each of ten maturity groups. Uniform Test 00 includes maturity Group 00 strains adapted to production in the northern fringe of the present area of soybean production. Uniform Tests 0 through IV include later maturing strains adapted to locations progressively further south in the North Central States and areas of similar latitude. Each year new selections are added …

Developing Methods To Survey, Collect, Process, And Screen Endemic Entomopathogenic Fungi Against The Asian Citrus Psyllid In The Lower Rio Grande Valley, Jonathan Cisneros

Theses and Dissertations

The Asian citrus psyllid (ACP), Diaphorina citri Kuwayama (Hemiptera: Liviidae), vectors “Candidatus Liberibacter spp.”, the causative agent of Citrus Greening Disease. Managing ACP is imperative given the continuous increase in HLB positive trees. An aspect of integrated pest management (IPM) is the use of entomopathogenic fungi for the biological control of D. citri.

In order to identify endemic entomopathogenic fungi actively infecting D. citri, ACP were collected from local residential areas, surface sterilized, and plated on a semi-selective agar medium. Collection of over 9,300 samples from 278 sites throughout the LRGV led to the positive identification of …

Incorporation Of Native Plants For Biodiversity Conservation In South Texas Agroecosystems, Kaitlynn M. Lavallee

Theses and Dissertations

I address the concerning disconnect between food production and regenerative ecological principles. First, understanding the foundational processes of seed-dormancy and germination are essential for successful restoration efforts using native species. We examine four common seed treatments (aerated hydroprime, acid scarification, cold stratification, sand scarification) on twelve commercially available species native to south Texas. Pappophorum bicolor Fourn. (pink pappusgrass) was sown in the field with the aerated hydroprime treatment, D. virgatus (Willd.) B.L. Turner (prostrate bundleflower) was planted after sand scarification treatment, and Ratibida columnifera (Nutt.) Woot. & Standl. (Mexican hat) was seeded without treatment. Small-scale field trials were conducted to …

Native Plant Allelopathy: A Potential Approach To Limit Invasive Grass Encroachment In Thorn Forest Restoration, Emily A. Mullins

Theses and Dissertations

Less than 5% of the Tamaulipan thorn forest remains in the United States. For this reason, there have been many attempts at restoration of this ecosystem. Oftentimes these attempts are unsuccessful due to the high prevalence of invasive African grasses that outcompete the seedlings. In an effort to improve the efficacy of these restoration efforts, native plant allelopathy has been examined for its ability to exclude invasive guineagrass. Native species were surveyed and selected species were tested for allelopathy in laboratory bioassays. The species that exhibited allelopathy in the laboratory were then evaluated in pot experiments for their ability to …

Improving Sustainable Fertilizer Practices For Pomegranate By Leaf Nutrient Concentration Evaluation And Fertilizer Trials, Minh Le

Master's Theses

Fruit tree leaf nutrient concentrations are commonly used to determine fertilizer rates, but information is limited regarding nutrient requirements, seasonal N uptake and removal rates, and soil N dynamics for pomegranate. Relationships between fertilizer rates, leaf nutrient concentrations, fruit yield and quality were examined in five mature, commercial California ‘Wonderful’ pomegranate orchards. Site 1 was observed for two growing seasons (2018-2019) and sites 2-5 were observed for one season (2018 or 2019). In 2018, 150, 300, or 450 g N/tree was applied at sites 1-3 in a single application at early fruit development or in two equal applications at early …

Eelgrass (Zostera Marina) Population Decline In Morro Bay, Ca: A Meta-Analysis Of Herbicide Application In San Luis Obispo County And Morro Bay Watershed, Tyler King Sinnott

Master's Theses

The endemic eelgrass (Zostera marina) community of Morro Bay Estuary, located on the central coast of California, has experienced an estimated decline of 95% in occupied area (reduction of 344 acres to 20 acres) from 2008 to 2017 for reasons that are not yet definitively clear. One possible driver of degradation that has yet to be investigated is the role of herbicides from agricultural fields in the watershed that feeds into the estuary. Thus, the primary research goal of this project was to better understand temporal and spatial trends of herbicide use within the context of San Luis …

Optimization Of In-Vessel Food Waste Composting: Enzyme Activity And Microbial Dynamics, Ayawovi Selom Ametepe

Graduate Theses and Dissertations

A series of greenhouse-based, rotary-drum bioreactor experiments was designed to study microbial dynamics and enzyme activity during optimization of food waste composting. This work aims to optimize food waste composting by defining the best food waste-to-bulking agent proportion controlling conditions and by evaluating the food waste composting process when inoculated by a bacterial inoculant product compared to uninoculated compost. Three experiments were run in total. The two first experiments were conducted for 48 days with sampling at each step of composting, while the third experiment last 50 days and included one extra sampling date. In the first experiment, 50:50, 65:35 …

Influence Of Burning And Grazing Management Practices On Subirrigated Sandhill Meadow Hay Production, Tara M. Harms

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

Subirrigated meadows are a valuable forage resource to Sandhills ranching operations being used for hay production, grazing, or a combination of both. Practices that sustain meadow productivity should be encouraged to ensure a consistent feed supply for cattle. The potential influence of prescribed burning or pre-freeze and post-freeze grazing on forage production and quality are not well understood on these meadows. In grasslands, including meadows, excess dead plant material can accumulate, causing a potential reduction in forage yield and quality. Results of our three-year field study suggest that burning meadows in the spring is a suitable management option to remove …

Fungicide Resistance: Surveillance, Risk Assessment And Evolution In Two Soil-Borne Pathogens, Nikita Gambhir

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

Fungicide-resistant pathogens are an increasing threat to fungicide efficacy and plant health. The goal of this dissertation was to advance the foundational knowledge required to prevent and detect fungicide resistance development in the seedling disease pathogen, Rhizoctonia zeae and the white-mold pathogen, Sclerotinia sclerotiorum. Corn and soybean fields in 12 states (Iowa, Illinois, Indiana, Kansas, Kentucky, Michigan, Minnesota, Missouri, North Dakota, Nebraska, South Dakota, and Wisconsin) were surveyed for R. zeae. In vitro fungicide sensitivity was determined for 91 isolates to fludioxonil, sedaxane, and/or prothioconazole. Rhizoctonia zeae was sensitive to all fungicides (EC₅₀ < 3 µg/ml) except azoxystrobin (EC₅₀ > 100 µg/ml). In …