Life Sciences Commons^™

Evaluation Of Warm Season Vegetables Using Sustainable Production Practices, Jacob Arthur

Theses and Dissertations

Sustainable practices were evaluated for the production of two warm season vegetable crops, tomato and chile peppers. The first study investigated the plant vegetative growth, fruit production timing, yield components and fruit quality of three hybrid and three heirloom tomato cultivars grown in a high tunnel using grafted and non-grafted plants. Grafting the selected tomato cultivars with the two rootstock types did not alter total marketable yield of any cultivar, but affected overall stem diameter, fruit color, and β-carotene concentrations of tested tomato cultivars. The second study evaluated the plant growth, yield, and fruit quality of nine heirloom chile pepper …

Metagenomic Analysis Of Root-Associated Microbiome Of Healthy And Taproot Decline-Affected Soybeans And Identification Of Healthy Soybean Root Endophytes With Protective Activity Against The Causal Agent, Xylaria Necrophora, Uyen Wesser

Theses and Dissertations

Plant roots are associated with a diverse microbial community of bacteria and fungi. The root microbiome communities associate with the root surface or penetrate the superficial layers of root tissues. It is of high agronomic interest to characterize root microbiomes and identify microbes with beneficial effects on plant defense against pathogens. Soybean taproot decline (TRD) is an emerging soil-borne disease caused by a fungus classified as Xylaria necrophora, challenging to control and with devastating effects on yield. Our group has initiated a study of the soybean root microbiome with three primary experiments: (I) perform a comparative study of root …

United We Stand? Investigating The Impact Of Unified Dues Agreements Between State And National Career & Technical Education (Cte) Professional Organizations On Cte Funding In The Southern States, Justin Ryan Hall

Theses and Dissertations

Career and Technical Education (CTE) teachers have long been active in lobbying the federal and state governments in support of CTE through their professional organizations, but these are not traditionally considered interest groups. This study sought to determine if the formal relationships—dues agreements—between the two largest national professional organizations, and their state affiliates had an impact on state funding for CTE. The impacts of professional organization unity, membership rates, and lobbying expenses on state-level CTE funding were analyzed through the lens of interest group theory, a subfield of political science. Within this population (N = 13), 1) a link …

The Effects Of Glyphosate Salts And Volatility-Reducing Agents (Vra) On Dicamba Volatility, Nicole Glenn

Theses and Dissertations

Dicamba is often tank mixed with glyphosate to increase herbicidal efficacy but may contribute to off-target movement (OTM). In recent years, volatilization has become problematic for dicamba-containing herbicides, resulting in increased regulatory requirements necessitating the use of volatility-reducing agents (VRA) for application. Research was conducted in 2021 and 2022 using low tunnels in a field environment and humidomes in a greenhouse environment to further assess how glyphosate salts and VRAs affect dicamba volatility. Our data indicate that the inclusion of glyphosate to dicamba can increase dicamba volatility, depending on the glyphosate salt used. The inclusion of the evaluated VRAs will …

Evaluation Of Novel Litter Amendments For Use In The Commercial Broiler Industry, Jorge A. Urrutia

Theses and Dissertations

Poultry litter amendments (LA) are commonly used to maintain good litter quality; the most common ones; are acidifiers. However, concern over the lifespan of LA acidifiers (d) and corrosive nature revealed a need for alternative LA. Products of interest include biochar (BC), superabsorbent polymers (SAPs), and alum mud (AM). Experiment 1 was a screening study (n=17 treatments, no birds) conducted to determine the optimal application rate/method of BC, SAPs, and AM vs.commercial LA and a control. Most SAPs treatments measured metrics may be similar (i.e., bacteria, water activity) or better (pH) vs. commercial LA (PLT). High inclusions of novel LA …

An Assessment Of Physical And Microbial Dynamic Properties Sensitive To Tillage Practices In Hidalgo Sandy Clay Loam Soils, Rocio N. Hernandez

Theses and Dissertations

Mechanized tillage is known to impact the dynamic physical, biological and chemical properties of a given soil, and as a result, can cause systematic harm to the soil’s function (Alam et al., 2014). The aim of this study is to assess how a series of land management tillage practices will impact dynamic physical and biological soil health parameters such as aggregation, carbon, respiration, and enzymatic activity (β-glucosidase). According to Acir et al (2020), the aforementioned soil parameters are both co-influenced and dependent, indicating a response to tillage is likely. A total of 198 samples of Hidalgo series soils were collected …

Grapefruit Peel Biochar Applications For Immobilizing Copper And Lead In Soil, Michael Alfredo Navarro

Theses and Dissertations

This study investigated the efficacy of grapefruit peel (GP) derived biochar materials (two pyrolysis temperatures 450°C and 800°C) as a potential adsorbent to immobilize heavy metal (copper and lead) in a local sandy loam clay soil. A batch adsorption test with heavy metal concentrations at 50 mg L-1, and 100 mg L-1 revealed that soil itself had the highest immobilization percentage compared to the GP biochars. A soil column experiment was conducted to determine how much the GP biochar samples and the tested soil will exhibit adsorptive characteristics for heavy metals when 50 ml of 50 mg L-1 copper or …

Weather Parameters Influencing The Incidence Of Citrus Canker Caused By Aw Strain In The Rio Grande Valley, Amit Sharma

Theses and Dissertations

Citrus canker caused by bacterium Xanthomonas citri subsp. citri (Xcc) seriously affects the citrus industry by making the fruit unmarketable due to unsightly lesions on the fruit. Canker caused by Aw strain of Xcc was reported in the citrus trees located in the residential areas of the Rio Grande Valley (RGV). Canker severity differs amongst cultivars/varieties, and it is influenced by prevailing environmental conditions. Multiple regression modeling of the disease incidence with the environmental variables such as temperature, humidity, windspeed, wind gust, and rainfall was performed to understand the environmental conditions that are favorable for spread of citrus …

Dynamic Soil Properties In The Lower Rio Grande Valley: Understanding Responses Of Infiltration Rate, Bulk Density, Aggregate Stability To Different Tillage Practices, Temiloluwa Faith Awotoye

Theses and Dissertations

Dynamic Soil Properties (DSPs) are soil properties that change in response to both natural and human-caused interruptions and pressures such as agro-based and wildland management. These soil properties can transform for months or even years in response to the farm use and management procedures. This research project investigates the relationship between different dynamic soil physical properties and tillage practices in the Texas Hidalgo sandy clay loam benchmark soil series. Data analyses was done to compare the effect of tillage to these soil physical properties and build a discussion about relationships between on-farm practices to other aspects of farm viability. We …

Incorporating Native Plants In Insectary Strips To Promote Insect Diversity And Below-Ground Beneficial Microbes In South Texas, Lindsey N. Richards

Theses and Dissertations

Farm edges are generally the most undisturbed areas in a farm with diverse vegetation and can enhance agrobiodiversity and provide crucial food and shelter for wildlife, insects, and soil biota. Planting native wildflowers with the ability to reseed and withstand local climatic conditions for semi-permanent vegetation around farm edges or in between crops has potential to biologically control pests. To test this, we ran a two-year study and installed three different flowering insectary strips on a certified organic vegetable farm in South Texas during the winter season. The treatments were: 1) a commercially sourced 17-species native wildflower seed mix; 2) …

The Employability Of State Ffa Degree Recipients In Alabama, Kailee D. Johnson

Theses and Dissertations

Many high schools have shifted from comprehensive graduation exams to a focus on College and Career Readiness. A common method used to determine when a student is college and career ready is a Career Readiness Indicator (CRI). Many CRIs demonstrate a benchmark learning goal for students. Among academic-based CRIs are Career and Technical Education (CTE) industry credentials. Credentials are just one way that agriculture classrooms contribute to student success. This study compiled existing research on CRIs and employability skills in CTE students to determine how the State FFA Degree could potentially fit into this category as well as highlight specific …

Effects Of The In Ovo Administration Of The Poulvac E. Coli Vaccine In Layer Hatching Eggs On Hatchability, Hatchling Characteristics, And Early Posthatch Chick Performance, Lauren L. Lindsey

Theses and Dissertations

Avian Pathogenic E. coli can lead to infections in laying hens and wide-spread economic problems in the table egg industry. A vaccine widely used to combat APEC is the Poulvac E. coli vaccine, which is normally applied via spray vaccination. Application of this vaccine via in ovo injection has not been examined. The purpose of this series of studies was to determine the effects of injecting 50 μL of different dosages of the PECV into Hy-Line W-36 layer hatching eggs on the hatchability and characteristics of the hatchlings, and on the livability and characteristics of the chicks through 21 d …

The Relationship Between Leadership Preference Of County Level Personnel Within University Of Missouri Extension And Their Level Of Employee Engagement, Jason C. Morris

Theses and Dissertations

The purpose of this study was to describe the perceived leadership style of the University of Missouri Extension Service county staff and their level of engagement and study the relationship between variables. Administrators with University of Missouri Extension Service can utilize this information to better serve Extension Staff and ultimately people throughout the state of Missouri.

The Vannsimpco Leadership Survey was used to measure the perceived leadership style of county level staff. The Utrecht Work Engagement Scale (UWES) was used to measure work engagement on three constructs: vigor, absorption, and dedication engagement. Demographic characterizes of county level staff was also …

Sustainable Sidedress Nitrogen Applications For Early Corn And Cotton Crops Using Small Unmanned Aerial Systems, James Nolan Parker

Theses and Dissertations

Nitrogen run-off from agriculture have been linked to human health problems on a global level. Large-scale conventional producers struggle to redefine themselves as sustainable because reducing nitrogen (N) inputs without justification or validation may lead to severe profit losses. Small unmanned aerial systems (sUAS) sensing may allow for decreased N runoff. Failure to address this problem will exacerbate already excessive N runoff into the Mississippi River and beyond. The purpose of this study was to reduce fertilizer N input using sUAS technology to assess crop canopy needs. In 2020 and 2021, variable rate nitrogen (VRN) side-dress N application maps were …

The Impacts Of The Covid-19 Pandemic On The Food Security Of Mississippians, Hannah Noel Irwin

Theses and Dissertations

Mississippi leads the United States in food insecurity, with 15.3% of Mississippians experiencing food insecurity in a given year. To determine the impacts of the COVID-19 pandemic on the food insecurity of Mississippians, a survey containing the USDA Household Food Security Questionnaire was distributed to adult Mississippi residents. By employing the USDA Household Food Security Scale and the Foster-Greer-Thorbecke Methodology, this study finds that the food insecurity rate, food insecurity gap, and squared food insecurity gap have worsened in Mississippi since the beginning of the COVID-19 pandemic. Additionally, this study finds that households which were food insecure prior to March …

Assessing Virtual Free-Choice Agricultural Learning: A Mixed Methods Approach, Richard John Kennedy

Theses and Dissertations

Since the mid-19th century, agricultural museums and living history sites, first in Scandinavia and then in the United States and Canada, have provided historical, cultural, and, sometimes, scientific information about farming to visitors. Many of these visitors have been school children on field trips. Assessment of this learning, however, has been scant, particularly within the free-choice style inherent in these types of educational venues. At the same time, assessment of free-choice learning, often analyzed through the Contextual Model of Learning (Falk & Dierking 2000), has taken place at educational sites like zoos, natural history museums, and science centers. This study, …

Quantifying And Predicting Drought Performance In Woody Semi-Arid Seedlings In South Texas: Implications For Enhancing Drought Resilience In Restoration, Zarek Contreras

Theses and Dissertations

Increasingly frequent and severe droughts in the Lower Rio Grande Valley National Wildlife Refuge have been observed to cause large variation in species-specific mortality patterns in young seedlings, spanning 6 – 43 % mortality within the first year. To understand the underlying mechanisms behind this, we subjected seedlings of five woody semi-arid species (Celtis pallida, Forestiera angustifolia, Sideroxylon celastrinum, Phaulothalmnus spinescens, and Zanthoxylum fagara) to a point-of-no-return drought experiment in order to (1) identify potential metrics capable of predicting species wilting and mortality responses, and (2) to understand the underlying mechanisms that correspond to species drought performance …

Assessment Of Nitrogen-Based Fertilizer Transport And Microbial Activities In Sandy Soil Profiles In South Texas, Gladys De La Rosa

Theses and Dissertations

Conventional farming is a common practice in Lower Rio Grande Valley (LRGV) and the application of nitrogen fertilizer is essential for plant growth and support. However, managing the rate of nitrogen that is applied can benefit farmers financially and reduce nitrate leaching that can have an adverse effect on the local environment and aquatic systems, e.g., rivers and estuaries. Sandy soils are more vulnerable to water infiltration due to the large proportion of macropores. This study aims to (i) assess how nitrate from a variety of fertilizers (i.e., synthetic and organic) distributes on the top 60 cm layer of a …

Revealing The Effects Of Climate Change And Fungicides On Soil Microbial Communities In The Lower Rio Grande Valley, Texas, Armida Rivera

Theses and Dissertations

Fungicide applications are effective to prevent fungal pathogens that are known to cause crop damage and decrease yields. However, these pesticides can exert toxic or inhibitory effects on non-targeted organisms such as soil microbial communities. In addition, it is unknown to what extent shifts in temperature and soil moisture resulting from global climate change, alter the activities of non-targeted soil organisms. The aim of this study was to evaluate soil biological parameters such as soil respiration and enzyme activities involved in the cycling of carbon, nitrogen, and phosphorous (Beta-glucosidase, Fluorescein Diacetate (FDA) Hydrolysis, urease, alkaline phosphatase, acid phosphatase, and N-acetyl-Beta-glucosaminidase) …

Determining Residual Control And Systemic Activity Of Commonly Used Insecticides In Soybean And Cotton, Jacob H. Smith

Theses and Dissertations

Chemical control is a critical component of integrated pest management in cotton and soybean production. Residual efficacy of foliar insecticides can be highly variable and difficult to quantify due to several factors. The purpose of this research was to determine residual control and concentrations in flowering structures of commonly used insecticides. This research focused on the concentrations of active ingredient within the plant as well as efficacy over time. Previous research suggested chlorantraniliprole had a long residual and was highly lethal on corn earworm up to 28 days after treatment (DAT) in soybean; however, the results found in cotton were …

Evaluating Soil Health Changes Following Cover Crop And No-Till Integration Into A Soybean (Glycine Max) Cropping System In The Mississippi Alluvial Valley, Alexandra Gwin Firth

Theses and Dissertations

The transition of natural landscapes to intensive agricultural uses has resulted in severe loss of soil organic carbon (SOC), increased CO₂ emissions, river depletion, and groundwater overdraft. Despite negative documented effects of agricultural land use (i.e., soil erosion, nutrient runoff) on critical natural resources (i.e., water, soil), food production must increase to meet the demands of a rising human population. Given the environmental and agricultural productivity concerns of intensely managed soils, it is critical to implement conservation practices that mitigate the negative effects of crop production and enhance environmental integrity. In the Mississippi Alluvial Valley (MAV) region of Mississippi, USA, …

Is Agriculture Being Implemented In Private School Classrooms? The Impact Of Teacher Willingness And Availability Of Resources., Casey Moss

Theses and Dissertations

Agricultural literacy has been a topic of concern as most of the population have little to no understanding of agriculture, and the impact it has on society. Agricultural literacy can be defined as “having knowledge and understanding of agriculturally related scientific and technologically based concepts and processes required for personal decision making” (Meischen & Trexler, 2003, p.44). Numerous studies have been conducted to determine the significance of agricultural literacy beginning with elementary aged children and continuing through high school. The majority of studies conducted focus on public school students and teachers. This has led to a gap in the knowledge …

Evaluating Cover Crops To Determine The Best Management Practice For The Suppression Of Tall Waterhemp And Italian Ryegrass, Samuel R. Reeves

Theses and Dissertations

To combat herbicide resistance among weeds, non-herbicide methods of control, such as cover crops, are becoming widely adapted. Experiments were conducted to determine how to effectively establish and manage cover crops in order to suppress tall waterhemp and Italian ryegrass and to assess their overall impact on soybean growth and yield. Various cover crop establishment methods were evaluated, and it was determined that interseeding at the R7 growth stage of soybean was the least effective method for proper cover crop establishment. Biomass data demonstrated that interseeding created the least amountof cover crop biomass, with no differences found among the other …

Plugging Into A New Age: The Impact Of Social Media Use On Undergraduate Students’ Perceptions Of Production Agriculture And Consumer Decisions, Shannon K. Allen

Theses and Dissertations

Today, 84% of young adults between the ages of 18-29 use at least one social media site (Pew Research Center, 2020) and are in the stages of emerging adulthood where they are making independent decisions for the first time (Arnett, 2000). As society becomes more technologically advanced, we become further removed from agriculture (Powell & Agnew, 2011; Dale et al., 2017). Thus, resulting in a separation between consumer and producer (Wilson & Lusk, 2020; Holt & Cartmell, 2013). This leaves the opportunity for society to turn to social media for agriculture information leading to negative perceptions of agriculture (Eyck, 2000; …

The Guatemala Rabbit Project: A Household Agricultural Intervention Program Evaluation Using The Re-Aim Framework, Jessica Martin Graves

Theses and Dissertations

Amongst the breathtaking and mountainous landscapes of the Western Highlands is a highly indigenous Mayan population stricken with challenges of food insecurity and extreme poverty. Despite efforts by governmental and non-governmental organizations alike to combat these challenges, the results of chronic malnutrition have led to some of the highest child stunting rates in all of Guatemala, particularly in the department of Totonicapán, where this study took place. To date, information is limited regarding agricultural programs that utilize the rabbit as a model to reduce food insecurity in Guatemala. Thus, a novel agricultural education program, Guatemala Rabbit Project (GRP), was developed …

Quantifying The Effects Of Abiotic Stress On Early Season Growth, Development, And Physiological Characteristics In Corn, Charles Hunt Walne

Theses and Dissertations

Corn is one of American agriculture's greatest success stories, where we have witnessed incredible increases in yield potential over the last half-century. However, abiotic stress is still the primary limiting factor preventing plants from reaching their true yield potential. In addition, agriculture is not exempt from the deleterious effects of changing weather patterns and the altered climate our world will face as time progresses. Thus, increasing our understanding of how crops interact with their environment both above and below the soil will be crucial to increasing production on a global scale while maximizing profitability at a local level. Five studies …

Perceptions Of Middle School Students On Gardening, Julie B. White

Theses and Dissertations

The purpose of this study was to describe the perceptions middle school students had about agriculture and gardening as part of the GrOW (Gardening and Overall Wellness) Program. This included multiple constructs, including students’ gardening efficacy, perceptions of those who had already completed the GrOW Program, perceptions of those who had not completed the GrOW Program, and students’ future interests in gardening. The population for this study was sixth-grade students at the Partnership Middle School in Starkville, Mississippi. A quantitative instrument was used to assess the perceptions of the students (n = 222).

Overall, students had positive perceptions about the …