Agriculture Commons^™

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 …

Cardenolide, Potassium, And Pyrethroid Insecticide Combinations Reduce Growth And Survival Of Monarch Butterfly Caterpillars (Lepidoptera: Nymphalidae), Annie J. Krueger, Emily A. Robinson, Thomas J. Weissling, Ana M. Vélez, Troy D. Anderson

Department of Entomology: Faculty Publications

The monarch butterfly, Danaus plexippus L., has evolved to be insensitive to milkweed cardenolides via genetic modifications of Na⁺/K⁺-ATPase. There is concern for insecticide exposures near agriculture, with little information on monarch caterpillar toxicology. It is unclear how cardenolide insensitivity may affect the sensitivity of monarch caterpillars to pyrethroid insecticides. Additionally, potassium fertilizers may affect monarch caterpillar physiology and cardenolide sequestration. Here, we investigated the growth, survival, and development of caterpillars exposed to the cardenolide ouabain, bifenthrin, and potassium chloride (KCl) alone and in combination. Caterpillars were either exposed to (1) ouabain from third- to fifth-instar …

Publisher Correction: The Genome Of The Stable Fly, Stomoxys Calcitrans, Reveals Potential Mechanisms Underlying Reproduction, Host Interactions, And Novel Targets For Pest Control (Bmc Biology, (2021), 19, 1, (41), 10.1186/S12915-021-00975-9), Pia U. Olafson, Serap Aksoy, Geoffrey M. Attardo, Greta Buckmeier, Xiaoting Chen, Craig J. Coates, Megan Davis, Justin Dykema, Scott J. Emrich, Markus Friedrich, Christopher J. Holmes, Panagiotis Ioannidis, Evan N. Jansen, Emily C. Jennings, Daniel Lawson, Ellen O. Martinson, Gareth L. Maslen, Richard P. Meisel, Terence D. Murphy, Dana Nayduch, David R. Nelson, Kennan J. Oyen, Tyler J. Raszick, José M.C. Ribeiro, Hugh M. Robertson, Andrew J. Rosendale, Timothy B. Sackton, Perot Saelao, Sonja L. Swiger, Sing Hoi Sze, Aaron M. Tarone, David B. Taylor, Wesley C. Warren, Robert M. Waterhouse, Matthew T. Weirauch, John H. Werren, Richard K. Wilson, Evgeny M. Zdobnov, Joshua B. Benoit

United States Department of Agriculture-Agricultural Research Service / University of Nebraska-Lincoln: Faculty Publications

Following publication of the original article [1], it was reported that the article copyright was incorrect. The correct copyright statement is: © This is a U.S. Government work and not under copyright protection in the US; foreign copyright protection may apply 2021. The original article [1] has been corrected.

Genetic Fingerprinting And Aflatoxin Production Of Aspergillus Section Flavi Associated With Groundnut In Eastern Ethiopia, Abdi Mohammed, Paola C. Faustinelli, Alemayehu Chala, Mashilla Dejene, Chemeda Fininsa, Amare Ayalew, Chris O. Ojiewo, David A. Hoisington, Victor S. Sobolev, Jaime Martínez-Castillo, Renee S. Arias

United States Department of Agriculture-Agricultural Research Service / University of Nebraska-Lincoln: Faculty Publications

Background: Aspergillus species cause aflatoxin contamination in groundnut kernels, being a health threat in agricultural products and leading to commodity rejection by domestic and international markets. Presence of Aspergillus flavus and A. parasiticus colonizing groundnut in eastern Ethiopia, as well as presence of aflatoxins have been reported, though in this region, no genetic studies have been done of these species in relation to their aflatoxin production. Results: In this study, 145 Aspergillus isolates obtained from groundnut kernels in eastern Ethiopia were genetically fingerprinted using 23 Insertion/Deletion (InDel) markers within the aflatoxin-biosynthesis gene cluster (ABC), identifying 133 ABC genotypes. Eighty-four isolates …

Effects Of Nitrogen Management And Cultivar On Strawberry Production Under Disease Pressure, Kamille A. Garcia-Brucher

Master's Theses

Effects of nitrogen management and cultivar on strawberry production under disease pressure

Kamille Garcia-Brucher

California strawberry growers face increasing regulatory pressures to manage nitrogen (N) applications in their production system. Standard practice in the California strawberry industry is to apply a synthetic pre-plant controlled release fertilizer (CRF) to ensure the crop has sufficient N during winter establishment. Some research from the UC Cooperative Extension suggests this practice is not efficient at delivering N to the crop since most of the N is released from CRF before strawberry crop N uptake is significant. Another concern for California strawberry growers is loss …

An Assessment Of The Needs Of School-Based Agricultural Educators And Other Professionals In Agricultural Service Agencies For A Professional Online Master’S Degree In Agricultural Education, Maria Mercedes Rossi

All Dissertations

Online learning is one form of distance education mediated through information and communications technology such as the Internet or other technologies. The teaching content is delivered online, and instructors develop teaching modules that enhance their learning and interactivity (student-student, teacher-student, and content-student). Using social cognitive theory (SCT) concepts, the research team developed and validated a multidimensional instrument tool to assess the needs for a professional online master’s degree in agricultural education. The study aimed to assess participants’ readiness and motivations to learn online and identify participants’ needs and experience with online learning. Participants’ perceptions of online learning were assessed and …

Comparing Organic And Conventional Yield Responses To Climate Variations, Joost Wilken Meyer

Graduate Theses and Dissertations

This thesis compares the responses of organic yields and conventional yields towards climate variations. To achieve this objective, weather variables such as growing season weather conditions (average temperature, precipitation, cloud cover, relative humidity, drought index), weather anomalies, the occurrence of severe or extreme droughts and excessive rainfalls, are combined with 23 data sets gathered from previous studies that compare organic and conventional yields from the same location and time periods. To narrow the scope, the thesis focuses on soybean, maize, and wheat production in Europe and North America. Study-level fixed-effects models are used to control for any time-invariant factors such …

Effects Of "Lemongrass Factor" On Galleria Mellonella Hemocytes, Jennifer C. Rice

Graduate Theses/Dissertations

The use of conventional chemical insecticides to control agricultural pest has become problematic as they may have a negative impact towards human health and the environment, resulting in a need to research alternative methods to insect pest control. Plant derived substances like essential oils have been used for generations as toxicants, repellants, and anti-feedants to control agricultural pest. More research is needed to understand how insect immune systems react to essential oils and if cellular immune responses of phagocytosis, encapsulation, and nodulation can be inhibited by such. Subjecting Galleria mellonella to various concentrations of “lemongrass factor” lets the researcher/scientist know …

An Exploration Of The Role Of Farm Business Decisions In Addressing Financial Challenges For Missouri's Beginning Farmers, Lucas Paloschi

Graduate Theses/Dissertations

The next generation of farmers takes an important role in the food production for subsequent years. The American Farm Bureau Federation’s (2017) estimation that 70% increase of production will need to be achieved within the next 30 years set awareness across the globe. Researchers have been studying and trying to find means to aid beginning farmers in a variety of ways. This study measures farm decisions that affect financial performance of farmers aiming to facilitate beginning producers’ decision making. Three regressions were used to analyze how different variables affect farmers’ profitability and repayment capacity. Using a county-level data for the …

Is There Room In The United States Diet For Goat Meat? Analysis Of The 2019 National Goat Meat Survey, Everett Marcus Martin

Graduate Theses/Dissertations

Demand for goat meat has steadily increased in the past decade, but few studies have been conducted addressing goat meat attributes and demographic factors on consumers’ willingness to buy goat meat products. Analyzing a national consumer survey on goat meat preference, a logit modeling is used addressing factors affecting willingness to buy three goat meat products: grass-fed, locally grown, and organically raised. Results indicate that quality and freshness attribute characteristics significantly affect consumer willingness to buy grass-fed, organic, and locally grown goat meat.

Assessing Freezing Effect On Kiwifruit Cultivars And Mapping Suitable Areas For Growing The Crop In Eastern Texas, Lais De Oliveira Machado

Electronic Theses and Dissertations

Kiwifruit is a perennial vine originating from China where it has been grown for centuries. In the United States, green kiwifruit (Actinidia deliciosa) is primarily produced commercially in California. They are fuzzy, green fleshed and well known in the marketplace. Kiwifruit plants require low to moderate soil pH, adequate winter chilling and adequate precipitation to guarantee plant development and good fructification. Actinidia chinesis or golden kiwifruit are smooth skinned, feature golden flesh and are a more recent introduction into the global market. Kiwifruit crops have attributes that favor production in east Texas, including low pest problems, current long …

Greenhouse Gas Emissions From Two Contrasting Beef Systems From Birth To Slaughter In Eastern Nebraska, Levi J. Mcphillips

Department of Animal Science: Dissertations, Theses, and Student Research

Over the last 15 years, the increase in land use for corn and soybean has come at the expense of acres of grasslands and perennial forages employed in conventional beef-production systems. Implementing alternative cow-calf production systems into existing cropping systems may be a solution for reduced land availability and reducing total greenhouse gas emissions (GHG). Therefore, GHG from a conventional (CONV) pasture-based cattle production system with cows wintered on corn residue and summer grazing of brome pasture were compared to partial-confinement system (ALT) with cows and calves in a drylot during the summer and grazing cover crops and corn residue …

Small Grain Cereal Cover Crops For Late Fall Or Early Spring Grazing, Kallie J. Calus

Department of Animal Science: Dissertations, Theses, and Student Research

Beef cattle operations are confronted with early spring and late fall forage deficiencies. Producers in integrated crop and livestock systems can fill forage gaps using cover crops as a forage source in between cash crops.

A five-year study evaluating forage production, growing calf performance and economics of grazing an oats cover crop planted after corn silage (CS) and high moisture corn (HMC) corn harvests was conducted. The economic analysis accounted for costs of establishing and grazing the oats and the value of calf gain to determine fall grazing system profitability. Steers had greater average daily gain grazing oats after CS …

Management Of Late Summer Planted Annual Forages For Grazing And The Impacts Of Novel Sweet Bran Plus Products On Performance And Carcass Characteristics Of Beef Finishing Steers, Devin Anthony Jakub

Department of Animal Science: Dissertations, Theses, and Student Research

Two separate grazing studies were conducted to evaluate: 1) the effects of rapeseed inclusion into late summer planted oats on the performance of growing steers during late fall and winter (Exp. 1) and 2) the effects of forage allocation on forage utilization and performance of steers grazing a late summer planted oat-rapeseed mix (Exp. 2). Variation in the corn wet milling process can result in negative effects on animal performance, nonetheless, there remains interest in further exploration and refinement of corn wet milling byproducts to achieve optimal byproduct compositions and cattle performance. Thus, another experiment was conducted to evaluate the …

Impact Of Wood-Sourced Biochar On Carbon And Nitrogen Capture In Beef Feedlot Systems, Jessica L. Sperber

Department of Animal Science: Dissertations, Theses, and Student Research

A feedlot growing and finishing experiment evaluated the effect of including pine-sourced biochar at 0.8 (growing) and 1.0% (finishing) of dietary DM on steer performance, carcass characteristics, and greenhouse gas (GHG) production (Exp 1). Two nutrient mass balance experiments were conducted during winter and summer seasons to evaluate the effect of spreading unprocessed red cedar biochar on the feedlot pen surface on manure nutrient capture and cattle performance (Exp 2). In Exp. 1, the inclusion of biochar in the growing diet did not impact steer performance. The inclusion of biochar in the finishing diet significantly reduced intake and gain, resulting …

Utilizing Online Resources To Enhance Distribution Of Competitive Animal Evaluation Knowledge And Benefits, Brooke L. Parrish

Department of Animal Science: Dissertations, Theses, and Student Research

In recent years, the shift toward online education has revealed new challenges for learners to retain information, and for educators to find new and engaging ways to present content. This mixed methods, action research study explores the need and creation of online resources for competitive horse judging through surveys and pilot groups. The study was broken into four cycles. The first was an adult learner analysis survey, distributed through email Listservs and extension social media pages, to aid in answering the research questions: what expert horse judging instructors indicate their students should be learning, and what resources they need. Based …

Evaluation Of Cattle Management For Systems With Limited Perennial Pasture, Morgan Grabau

Department of Animal Science: Dissertations, Theses, and Student Research

Due to the conversion of perennial pasture and hay land to cropland in the western corn belt region, alternative methods of cow/calf management are being used to decrease reliance on perennial forages. These include grazing corn residue and feeding cow/calf pairs in confinement. Previous research has shown that limit-feeding a diet of low-quality forage and energy-dense co-products to cows in confinement is cost-effective. However, this strategy may limit the intake of the young calf and thus their performance. A study was conducted to evaluate the impacts of two alternative calf management strategies when pairs are in confinement, early weaning or …

Feeding A New Corn Milling Coproduct To Lactating Dairy Cattle: Examination Of Whole Animal Energy And Nitrogen Balance, Addison Lee Carroll

Department of Animal Science: Dissertations, Theses, and Student Research

New coproducts are continually developed in the ethanol production industry. With that, the new product originates from the dry milling process which is unlike the traditional process as nitrogenous based particles are concentrated from the residual fiber by sieving post fermentation. Although high protein coproducts have been available since the mid 2000’s. These new products must be evaluated for chemical composition so that they can be accurately described in feed libraries that are used in commercial ration formulation software. While chemical composition provides us an initial and useful description of a feed product, in vivo nitrogen and energy balance studies …

Host Genetics And Phenotype Associations Within The Bovine Rumen Microbiome, Waseem Abbas

Department of Animal Science: Dissertations, Theses, and Student Research

Rumen microbes have a symbiotic relationship with the host where the host provides a suitable environment and microbial fermentation fulfill nearly 70% of the energy needs of the host. Rumen microbes play a central role in host performance and health. To date, most rumen microbiome studies have focused on the influence of diet on microbial species composition. In addition to dietary factors, studies have suggested that host genetic markers could influence the colonization of gastrointestinal microbiota. However, our understanding of the host-microbiome interaction and how host phenotype is influenced by the rumen microbiome is limited. This dissertation demonstrates: (1) host …