Agriculture Commons^™

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 …

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) …

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 …

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, …

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 …

Growing Tea In Mississippi, Qianwen Zhang

Theses and Dissertations

Tea is the most popular beverage worldwide, second only to water. The United States is the third largest importer of tea in the world, importing a total of about 260 million pounds tea annually. With increased demand for locally sourced food products, questions are raised regarding whether domestic production of tea is feasible. Compared to major tea producing countries with centuries of growing history, tea production in the U.S. is limited and requires research support in many aspects of tea production. The objectives of this study were to investigate plant growth, leaf morphology, and seasonal chemical compositions in tea leaves …

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 …

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; …

Economic Aspects Of U.S. Catfish Farming: Technological Progress, Cost Of Regulations, And Economic Contribution, Shraddha Gurupad Hegde

Theses and Dissertations

This research provides a comprehensive picture of the economic status of the U.S. catfish industry through investigating several critical economic aspects such as technological progress, functional production relationships in intensive systems, regulatory costs, and economic contribution of the industry. The use of primary data is a unique aspect of this work reflecting the economic realities of catfish farms. Primary data collected through extensive in-person farm surveys covered over two-thirds of the catfish production areas in the U.S. The results of the study provided evidence of intensification in the U.S. catfish industry through increased adoption of two relatively new alternative production …

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 …

Evaluation Of Agronomic Performance And Weed Control In Soybean Grown With Different Row Configurations, Planting Dates, And Soil Textures, Franklin Read Kelly

Theses and Dissertations

Planting date, seeding rate, soil texture, and row configuration are important factors in soybean production. Each of these factors can impact overall production and yield of soybean immensely. Growers can have difficulty making decisions about how to best manage their production systems with these factors in mind. Therefore, research was conducted from 2019 to 2021 at the Delta Research and Extension Center in Stoneville, MS, to evaluate the agronomic performance, yield components, and weed control of soybean planted with different planting dates, row configurations, soil textures and/or seeding rates. Common row configurations utilized in Mississippi soybean production were compared to …

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 …

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 …

Effects Of The Inclusion Of Rice Hull Derived Bio-Oil On Wood Pellet Production, Tyler E. Lowe

Theses and Dissertations

Wood pellet production has become an advancing industry for the sake of reducing greenhouse emissions into the atmosphere especially, in European Union countries. Researchers and industry executives seek new methods and materials to improve the pelletization process. Rice hulls or husks has the potential to aid in wood pelletization as they possess high calorific values. This study focuses on using rice hull derived bio-oil from pyrolysis, which will also decrease ash content, as an additive to aid in the wood pelletization process. Using two groups of rice hull derived bio-oil as an additive in wood pelletization: Group 1 uses heavy …

Efficiency Of Weights Matrix Specification In The Spatial Error Model, Cannon Kent

Theses and Dissertations

This study investigates and quantifies the effect of different specifications of the spatial weights matrix (��) on estimates and inferences in the context of a regression model using the lattice perspective with polygon-type data. The study also investigates an alternative to the specification of �� by estimating a spatial variance-covariance matrix based on known features of the spatial data. Previous literature has addressed the a priori construction of �� and selection criteria but assumes point-type data. This study’s primary contribution is the setup of a true and known benchmark that allows the comparison of the different specifications of ��. This …

Assessing The Potential For Lightning-Induced Damage In Commercial Broiler Houses In Mississippi And Alabama, Matthew R. Rowland

Theses and Dissertations

Modern broiler houses are expensive to build, maintain, and insure. Protecting them from extreme weather events is a major concern to producers, integrators, and insurance companies. Lightning strikes can cause catastrophic fires and electrical damage and can lead to costly bird losses. A greater understanding of the impact of lightning on the commercial broiler industries of MS and AL is needed. The objectives of this research were collection of baseline resistance data for broiler houses and equipment in both states, and mapping lightning strike densities across MS and AL, evaluating annual, monthly, seasonal, and diurnal patterns. 63.5% of surveyed broiler …

Soybean (Glycine Max) Response To Multiple, Sublethal Exposures Of 2,4-D And Dicamba From Vegetative Through Reproductive Growth, Graham Robert Oakley

Theses and Dissertations

This study was conducted to determine whether soybean productivity is affected by multiple, sublethal herbicide exposures. The effects of dicamba and 2,4-D on soybean (Glycine max) productivity was investigated at 17 site-years. Relative to a single exposure of dicamba at R1, an additional exposure at either V3 or R3 reduced yield up to 23%. Three or more applications did not further decrease yields relative to an R1&R3 exposure. For 2,4-D, a single application to V3, R1, R3, or R5 soybean did not affect grain yield. However, two exposures of 2,4-D occurring from V3 through R3 reduced yield 5 to 7%. …

Examining The Need For Parental Satisfaction With The Msu Extension Equine Assisted Therapy Program, Ashlyn Ann Kiker

Theses and Dissertations

Animal assisted interventions are becoming more prevalent in our society. Animal interventions have become a popular therapy technique that exist to aid a variety of disabilities. Equine therapeutic riding has become one of the most popular forms of animal assisted therapy for both children and adults. While research shows the importance and benefits of animal assisted therapy for children, there is a lack of research concerning parental satisfaction within therapeutic riding programs.

This study tested a newly developed instrument for measuring parental satisfaction for therapeutic riding programs. The Parent/Caregiver Evaluation Tool (Kerr, 2021) was administered to parents/caregivers whose children participated …

Seasonal Management Strategies For Tarnished Plant Bug, Lygus Lineolaris (Palisot De Beauvois), In Midsouth Cotton Production Systems, Ryan Taylor Mann

Theses and Dissertations

The tarnished plant bug, Lygus lineolaris (Palisot de Beauvois), is considered the most economically important pest of midsouth cotton. This study was designed to understand the impact of tarnished plant bug populations in the later weeks of flowering cotton and residual effects of novaluron with subsequent applications. Experiments evaluated dynamic threshold approaches in the later flowering period of midsouth cotton, the impacts of novaluron plus subsequent applications at the 3^rd week of square, as well as residual properties in a laboratory experiment. Results suggest that a dynamic late season approach can reduce the amount of insecticide applications targeting tarnished …

Evaluation Of The Variable Rate Capabilities Of A Sprayer Equipped With Pulse Width Modulation Nozzle Control And Direct Chemical Injection Systems, William Walker

Theses and Dissertations

Variable-rate technologies coupled with broadcast spray systems serve to reduce chemical inputs, misapplication of chemicals, and environmental pollution, thus improving profitability and sustainability. Sprayer variable rate control involves using pulse width modulation (PWM) solenoids and/or direct chemical injection to adjust the application rate. The objectives of this research were to: outfit a conventional broadcast sprayer with PWM and direct inject technologies; evaluate the accuracy of the PWM system to control application rate for strait line and turn segments; and characterize the direct injection system’s transport delay time. For the PWM evaluation, the mean flow rate and coefficient of variation of …

Evaluating The Effects Of Pine And Miscanthus Biochar On Water Activity And Escherichia Coli Populations In Commercial Broiler Litter, Christopher Austin Marty

Theses and Dissertations

The decrease in subtherapeutic antibiotic administration in poultry has increased the need to address production challenges caused by pathogens, such as E. coli. One potential way to improve bird health and reduce bacterial infection is through the addition of litter amendments that absorb moisture. Biochar (BC) has previously been shown to increase water holding capacity in poultry litter, but its effects on E. coli mitigation are unknown. The objectives of this research were to 1) evaluate water activity of poultry litter amended with pine and miscanthus BC, and 2) determine the effects of different BC inclusion rates on litter …

Implementing Food Science-Based Instruction In Career Technical Education Courses, Jasmine D. Hendrix

Theses and Dissertations

Students are exposed to food concepts in agriculture-based career technical education (CTE) courses which provide a gateway for students to become more aware of food science career pathways. Professional development for Mississippi (MS) CTE teachers is needed to effectively implement food science-based instruction since there is not a food science curriculum framework adopted in MS. The objective of this study was to assess a food science professional development training for MS CTE teachers that would increase their self-perceived knowledge of food science, self-perceived ability to conduct food science skills, and their self-efficacy to implement food science-based instruction. Thirty-one teachers participated …

Effects Of Scarification, Phytohormones, Stratification, Soil Types And Warming On The Germination And/Or Performance Of Three Tamaulipan Thornscrub Species, Paula Luera

Theses and Dissertations

The Tamaulipan thornforests of south Texas and northeast Mexico are an ecologically and economically important conservation hotspot. Thornforest restoration is limited by native tree and shrub seedling availability for planting. Seedling shortages arise from low seed availability and knowledge gaps regarding best practices for germinating and growing the 70+ thornforest species desired for restoration plantings. To fill key knowledge gaps, we investigated three ecologically important thornforest species with low or highly variable germination or seedling survival rates: Ebenopsis ebano, Cordia boissieri, and Zanthoxylum fagara. For each, we quantified the effects of different dosages of chemical seed treatments …

Bullet-Proof Boll Weevil: The History Of Boll Weevil Eradication, Evan A. Berg

Theses and Dissertations

Farmers and entomologists have all experimented with various methods to find the best way to defeat the United States' boll weevil. The techniques themselves, while expansive, can be examined within the scope of the years that they were used. This provides an exciting insight into how cotton pest management became more complex as the decades moved on and revealed how the science of cotton pest management evolved to deal with the boll weevil and other future cotton threats.

A Gis-Based Model To Assess On-Site Sewage Facility (Ossf) Contamination Risk To Local Water Resources, Alvaro Garcia

Theses and Dissertations

In a collaborative effort between Texas Water Resources Institute (TWRI), Cameron County Public Health (CCPH), Texas A&M AgriLife Extension (TAMAE), and the University of Texas Rio Grande Valley (UTRGV), a GIS database that includes relevant OSSF information, such as location, system age, lot size, and other important parameters was created.

This OSSF database, along with publicly available GIS data, was used to create an integrative GIS-based risk assessment model where OSSF risk parameters were assigned a risk factor and combined into a spatial contamination risk for surrounding areas and their receiving waterbodies. Parameters were broken down into two categories: environmental …

Growth Kinetics Of Salmonella Spp. During Post-Harvest Storage Of Fresh And Fresh-Cut Papaya, Amandeep Singh

Theses and Dissertations

Fresh produce safety is major concern in United States. Fresh produce has been associated with numerous food-borne outbreaks each year. Salmonella has been a recurring issue in the papaya industry. Since 2010, imported papayas have been implicated in 8 multistate outbreaks associated with Salmonella spp. causing 480 illnesses, 113 hospitalization and 3 deaths. The main reason behind this problem is as fresh papaya is grown on fields where they are constantly exposed to preharvest microbial contamination through contaminated irrigation water, agricultural soil, raw manure and/or feces deposited by intruding domestic or wild animals. Moreover, majority fresh papaya is also consumed …

Variation In Trichome Types And Density Mediates Plant-Herbivore Interactions In Two Cucurbitaceae Members, Ishveen Kaur

Theses and Dissertations

Plant structural defenses such as trichomes and spines exert a significant selection pressure on insect herbivores. However, how species variation affects structural defense trait expression in closely related species is less understood. Through our studies, we tried to dissect the role of trichomes in mediating plant-insect interactions, in two non-model cultivated species in Cucurbitaceae: Lageneria siceraria, and Cucumis sativa family, and Trichoplusia ni as our major herbivore of interest. We observed that species differed in their attractiveness to different herbivores and their feeding behavior in common garden experiment. To tease apart structural and chemical defenses and their independent roles …

Some (Im)Material Girls, Living In (Im)Material Worlds, With Seeds, Stars, And Shit, Matthew Weiderspon

Theses and Dissertations

This writing situates material and gestural vocabularies cultivated in my artwork in relation to my lived experience; primarily my rural upbringing in Colorado. Scattered floor dispersals, calling sounds, and bodily movements desire reconsiderations of hope in precarity through a disorientation of place, association, scale, and language.

Status, Distribution, And Conservation Of The Black-Spotted Newt (Notophthalmus Meridionalis) In South Texas, Padraic S. Robinson

Theses and Dissertations

The Black-spotted Newt (Notophthalmus meridionalis) is a chronically understudied species, with much information on the natural history, ecology, and distribution of this species poorly known. Previous studies using traditional methodologies have had limited success detecting N. meridionalis. A novel eDNA assay was designed and implemented with the goal of better understanding N. meridionalis distribution in south Texas. Primers were designed to amplify N. meridionalis DNA and tested against DNA from sympatric amphibians. This assay combined with traditional methods was implemented at 62 sites throughout south Texas, and N. meridionalis was detected at eight localities. At each site …