Agriculture Commons^™

Two Essays On Food Environment, Nutrition, And Food Insecurity, Suliman Abdulaziz Almojel

Theses and Dissertations--Agricultural Economics

A healthy food environment is fundamental to good health. It contributes to the reduction of obesity and the development of healthy eating habits. In spite of this, many people in the United States (US) have been hypnotized to become obese due to the current food environment. Recently, the US has consistently ranked high in the world in terms of obesity. The rising rate is symptomatic of consuming unhealthy diets. Besides, the double-edged crisis of the US food environment and obesity poses a major threat to food security and public health. Therefore, studying the US food environment is important to sustain …

Vole Population Dynamics In Cover Crops Transitioning To Soybeans With Integrated Pest Management By Habitat Modification, Jena L. Nierman

Theses and Dissertations--Forestry and Natural Resources

The use of cover crops has been a wildly used method in rotational row crop production. Cover crops have minimized soil runoff and aided in maintaining nutrients in agricultural fields. Increased use of cover crops has seen a corresponding increase in the amount of damage done to soybeans by voles. Currently, there are no mitigation methods that successfully decrease vole populations in agricultural fields. The use of habitat manipulation as an integrated pest management solution has not been studied as a practical solution for vole population management. During 2019 and 2020, I tested the impacts of various cover crop termination …

Distribution And Diversity Of Heliothine And Other Lepidopteran Nudiviruses, Emrah Ozel

Theses and Dissertations--Entomology

Helicoverpa zea nudivirus 2 (HzNV-2) is the only known sterilizing and sexually-transmitted insect virus and causes pathological symptoms in H. zea reproductive tissues. HzNV-2 has features that make it a candidate as a H. zea (corn earworm) control agent, such as the ability to cause asymptomatic (latent) and symptomatic (lytic) infections and the ability to influence mating behavior of its host to favor virus spread. HzNV pathology has been studied and its genome sequenced, however, its prevalence in natural populations is largely unknown. In this study, we developed and used a low-cost PCR-based molecular survey to investigate HzNV-2 prevalence and …

Procuring Produce In A Rural, Appalachian County: A Thematic Analysis Of Community Member Experiences, Caroline Blincoe

Theses and Dissertations--Nutrition and Food Systems

Rates of obesity and other health disparities are exceptionally high in rural Appalachian counties compared to the nation as a whole. One causal factor of these health disparities in Appalachian counties is the inequitable allocation of healthy food. Food insecurity and the local food environment are large drivers for obesity experienced by Martin County, Kentucky residents. Successful socioecological model (SEM) and policy, systems, and environmental (PSE) interventions have shown promising results in reducing obesity and enhancing food security in this population. Through the transcription of semi-structured focus group interviews, thematic analysis aimed to obtain perspectives on the local food system. …

Incorporation Of Summer Annual Mixtures Into Grazing Systems In Kentucky, Kelly Marie Mercier

Theses and Dissertations--Plant and Soil Sciences

Utilizing summer annual grass-legume forage mixtures has the potential to improve forage yield and nutritive characteristics, and/or animal performance during times when cool-season pasture growth is limited by high temperatures. Legumes can utilize atmospheric nitrogen, which can increase crude protein and forage digestibility in mixtures. As nitrogen application generally improves both the yield and nutritive characteristics of summer annual forages, but can have a negative effect on legume competitiveness, nitrogen fertilizer recommendations for legume-containing summer annual mixtures are not well established.

Two experiments were conducted to determine the feasibility of utilizing summer annual mixtures in Kentucky, USA. The first experiment …

Nss, The Silencing Suppressor Of Tomato Spotted Wilt Orthotospovirus, Interferes With Ja-Regulated Host Terpenoids Expression To Attract Frankliniella Occidentalis, Jiao Du, Xiaoyu Song, Xiaobin Shi, Xin Tang, Jianbin Chen, Zhanhong Zhang, Gong Chen, Zhuo Zhang, Xuguo Zhou, Yong Liu, Deyong Zhang

Entomology Faculty Publications

Tomato spotted wilt orthotospovirus (TSWV) causes serious crop losses worldwide and is transmitted by Frankliniella occidentalis (Pergande) (Thysanoptera: Thripidae). NSs protein is the silencing suppressor of TSWV and plays an important role in virus infection, cycling, and transmission process. In this research, we investigated the influences of NSs protein on the interaction of TSWV, plants, and F. occidentalis with the transgenic Arabidopsis thaliana. Compared with the wild-type Col-0 plant, F. occidentalis showed an increased number and induced feeding behavior on transgenic Arabidopsis thaliana expressing exogenous NSs. Further analysis showed that NSs reduced the expression of terpenoids synthesis-related genes and …

Comparing Water Use Forecasting Model Selection Criteria: The Case Of Commercial, Institutional, And Industrial Sector In Southern California, Dilek Uz, Steven Buck

Agricultural Economics Faculty Publications

The United States is one of the largest per capita water withdrawers in the world, and certain parts of it, especially the western region, have long experienced water scarcity. Historically, the U.S. relied on large water infrastructure investments and planning to solve its water scarcity problems. These large-scale investments as well as water planning activities rely on water forecast studies conducted by water managing agencies. These forecasts, while key to the sustainable management of water, are usually done using historical growth extrapolation, conventional econometric approaches, or legacy software packages and often do not utilize methods common in the field of …

Behavioral Weather Insurance: Applying Cumulative Prospect Theory To Agricultural Insurance Design Under Narrow Framing, Tobias Dalhaus, Barry J. Barnett, Robert Finger

Agricultural Economics Faculty Publications

Experience across many countries shows that, without large premium subsidies, crop insurance uptake rates are generally low. In this article, we propose to use the cumulative prospect theory to design weather insurance products for situations in which farmers frame insurance narrowly as a stand-alone investment. To this end, we introduce what we call "behavioral weather insurance" whereby insurance contract parameters are adjusted to correspond more closely with farmers' preferences. Depending on farmers' preferences, we find that a stochastic multiyear premium increases the prospect value of weather insurance, while a zero deductible design does not. We suggest that insurance contracts should …

Impacts Of 1.5 °C And 2 °C Global Warming On Net Primary Productivity And Carbon Balance In China’S Terrestrial Ecosystems, Li Yu, Fengxue Gu, Mei Huang, Bo Tao, Man Hao, Zhaosheng Wang

Plant and Soil Sciences Faculty Publications

Assessing potential impacts of 1.5 °C and 2 °C global warming and identifying the risks of further 0.5 °C warming are crucial for climate adaptation and disaster risk management. Four earth system models in the Coupled Model Intercomparison Project Phase 5 (CMIP5) and a process-based ecosystem model are used in this study to assess the impacts and potential risks of the two warming targets on the carbon cycle of China’s terrestrial ecosystems. Results show that warming generally stimulates the increase of net primary productivity (NPP) and net ecosystem productivity (NEP) under both representative concentration pathway (RCP) 4.5 and RCP8.5 scenarios. …

Resistance And The Black Freedom Movement: Reflections On White’S Freedom Farmers, Garrett Graddy-Lovelace, Priscilla Mccutcheon, Ashanté Reese, Angela Babb, Jonathan C. Hall, Eric Sarmiento, Bradley Wilson

Geography Faculty Publications

First paragraphs:

Landmark: 1. An object or feature of a landscape . . . that is easily seen and recognized from a distance, especially one that enables someone to establish their location. Synonyms: mark, indicator, guiding light, signal, beacon, lodestar. 2. An event or discovery marking an important stage or turning point in something. Synonyms: milestone, watershed . . . major achievement. (“Landmark,” n.d., para. 1 & 4)

Dr. Monica White’s Freedom Farmers: Agricultural Resistance and the Black Freedom Movement stands literally as a landmark, ushering in a new era of community-based scholarship with and for agrarian justice. From here …

Thoroughbred Racehorse Welfare Through The Lens Of ‘Social License To Operate—With An Emphasis On A U.S. Perspective, Camie Heleski, C. Jill Stowe, Julie Fiedler, Michael L. Peterson, Colleen Brady, Carissa Wickens, James N. Macleod

Agricultural Economics Faculty Publications

This review addresses the question of whether Thoroughbred horse racing is sustainable in the context of current social values. A recently acknowledged framework, known as ‘Social License to Operate’ (SLO), provides us with a lens through which to view and assess racehorse welfare. In multiple surveys of the general public, the horse owning public, and university students, the primary topics of concern regarding Thoroughbred racing show considerable concordance: concern about catastrophic injuries—particularly as related to track surfaces, concern over the racing of two-year-olds, whip use by jockeys, drug/medication policies, and aftercare opportunities for retired Thoroughbred racehorses. Legitimacy of an industry, …

Evaluating The Economic Costs And Land Value Implications Of Implementing Cover Crops In Kentucky, Robert C. Ellis

Theses and Dissertations--Agricultural Economics

This thesis is comprised of two essays regarding the costs and impact of land values due to cover crops. This first essay uses a linear-programming resource allocation model combined with sequencing and machinery selection to optimize the practices and machinery utilization of a hypothetical western Kentucky grain farm. This was accomplished through maximizing returns over selected costs at various acreage adoption levels. Additionally, a decision tool was developed to assess the costs related to cover crop adoption. The results show a $30 per acre cost to adopt 1000 acres of cover crops when no benefits were considered. The second essay …

Virus-Induced Changes In Nuclear Proteins And Membranes In Nicotiana Benthamiana Cells, Caleb Mathias

Theses and Dissertations--Plant Pathology

Viruses rely on host proteins to complete their life cycles. This results in alterations to normal cell physiology to processes which benefit viral processes such as replication and movement to other cells. This may involve the relocalization of host proteins away from their original subcellular targets to sites which may benefit the virus, a process that is not as well understood as it relates to the nucleus. To identify nuclear proteins that may be involved in such processes, a library of random Nicotiana benthamiana cDNAs were expressed as GFP fusions in a transgenic marker lines expressing a histone 2B:RFP nuclear …

Optimizing Monarch Butterfly And Bee Conservation Efforts In The Urban Landscape, Adam M. Baker

Theses and Dissertations--Entomology

The eastern migratory population of monarch butterflies (Danaus plexippus) is in serious decline. Most of the efforts to conserve this iconic insect focus on habitat restoration in the US Midwest. Often overlooked are small butterfly-centric gardens that can act as stepping stones between urban and rural areas. These studies aim to optimize the conservation value of such gardens.

Eight milkweed (Asclepias) species varying in height, form, and leaf shape were compared over two years in a common-garden experiment. I measured milkweed growth, rhizome spread, and bloom periods, conducted bi-weekly counts of monarch eggs and larvae, evaluated …

Dynamic Balancing Of Foraging And Defensive Effort Contribute To The Optimality Of The Honey Bee Robbing Strategy, Grayson James Grume

Theses and Dissertations--Entomology

The optimality of a foraging strategy shifts in response to dynamic ecological conditions and the need to devote effort to other tasks. Nest defense and foraging effort in the honey bee may trade off as both tasks are performed by a shared workforce of physiologically-specialized individuals in exclusive roles. Honey robbing is a foraging strategy predicted to benefit from simultaneous increases in foraging and defensive effort, but may be constrained by workforce specialization. We developed a methodology to induce robbing behaviors with uninhabited bait hives. We used this methodology to evaluate foraging and defensive effort before and during robbing by …

Ecosystem Of Bagged Grain Stored Under Naturally Ventilated Warehouse: Analysis And Modelling, Michael Ayodele Omodara

Theses and Dissertations--Biosystems and Agricultural Engineering

Grain in Africa and indeed most developing parts of the world are stored in polypropylene or jute bags arranged in stacks of varied dimensions in naturally ventilated warehouses. This practice is, however, associated with high postharvest losses due to poor temperature and moisture management during storage. This constitutes a major economic and food security challenge in these countries. Therefore, this study characterizes changes in moisture content and temperature occurring in a stack of bagged corn by determining the permeability of bag materials that influence moisture transfer and developing a mathematical model of heat and mass transfer which incorporates the unique …

Aggregation Behavior In The Bed Bug, Cimex Lectularius L., Paul D. Baker

Theses and Dissertations--Entomology

The bed bug, Cimex lectularius L., is a common household pest that feeds on the blood of its human hosts. Unlike many other hematophagic arthropods, bed bugs have not demonstrated the ability to vector disease; yet its presence in a household often leads to fear and anxiety amongst its human host victims. Bed bugs spend the majority of their time aggregating in enclosed and hidden locations, making it difficult to detect and eradicate them. One of the significant mediators of aggregation behavior is an aggregation pheromone. The pheromone has been identified to be six chemical compounds, five volatile compounds that …

Management Of Sugarcane Aphid (Melanaphis Sacchari) Using Biological And Cultural Tactics In Kentucky, Nathan Harriman Mercer

Theses and Dissertations--Entomology

In 2013, a new aphid pest of sorghum, the sugarcane aphid Melanaphis sacchari Zehntner (Hemiptera: Aphididae), was found in the southern US, and caused significant yield loss in sorghum. Since then, M. sacchari has spread to most of the sorghum growing regions. Unmanaged populations can cause complete crop loss in grain, forage and sweet sorghum. M. sacchari cannot survive winters without a live plant tissue and must recolonize much of its pest range annually. Sweet sorghum (Sorghum bicolor) is an important crop for many growers in Kentucky, producing $16-25 million a year from its syrup. Biological control of …

Physiological Ecology Of Overwintering And Cold-Adapted Arthropods, Leslie Jean Potts

Theses and Dissertations--Entomology

Given their abundance and diversity, arthropods are an excellent system to investigate biological responses to winter. Winter conditions are being majorly impacted by climate change, and therefore understanding the overwintering biology of arthropods is critical for predicting ecological responses to climate change. In Chapters 2 and 3, I investigate the winter biology of a winter-active wolf spider. I show that winter-active spiders can take advantage of periodic prey resources and grown in the winter, which may allow them to get a jumpstart on spring reproduction. I also investigate spiders’ ability to track changes in their environment by quantifying low temperature …

Identification And Characterization Of Epigenetic Regulators In The Yellow Fever Mosquito, Aedes Aegypti, Shankar C. R. R. Chereddy

Theses and Dissertations--Entomology

Due to the increased interactions between the sylvatic and urban cycles of Aedes aegypti life cycle, there has been an increase in the incidence of vector-borne diseases. The risk involved through the transmission of viruses like Dengue, Zika, Yellow-fever and Chikungunya calls for an effective control method for the deadly vector. The possibility of pesticide resistance and the costs involved in producing new pesticides have pushed Sterile Insect Technique (SIT) into prominence. However, current methods used to sterize insects for SIT are not highly efficient. This study tackles current issues in mosquito control by identifying and characterizing epigenetic regulators that …

A Tangled Web: The Dynamics Of Endosymbiotic Infections In A Linyphiid Spider, Laura Cecilia Rosenwald

Theses and Dissertations--Entomology

Many arthropods are infected with bacterial endosymbionts that manipulate host reproduction, but few bacterial taxa have been shown to cause such manipulations. Mermessus fradeorum (Linyphiidae) is a sheet-weaving spider that displays both feminization and cytoplasmic incompatibility (CI). To correlate reproductive manipulations to endosymbionts, I surveyed the bacterial community of M. fradeorum using high throughput sequencing and found that individuals can be infected with up to five different strains of bacteria from the genera Wolbachia, Rickettsia, and Rickettsiella. Rickettsiella was found in all 23 tested spider matrilines. I used antibiotic curing to generate uninfected matrilines that I reciprocally crossed with …

Developing Alternative Practices For Management Of Flea Beetles Attacking Eggplant And Leafy Brassicaceous Greens, Robert Brockman

Theses and Dissertations--Entomology

Flea beetles are a challenging pest for many producers of vegetable crops in Kentucky. Chewing numerous small holes in the leaves of their host plants, high flea beetle populations can quickly overwhelm unestablished crops. I tested the efficacy of several alternatives to insecticides within brassicaceous leafy greens and eggplant. Four field trials in 2019 and 2020 compared essential oil sprays, the woven-mesh row cover ProtekNet, the spunbonded row cover Agribon, and reflective silver mulch to an untreated control, a conventional insecticide rotation of dinotefuran and pyrethroids, and an organic insecticide rotation of spinosad and pyrethrins. The silver reflective mulch was …

Management Of Stink Bugs (Hemiptera: Pentatomidae) On Soybean In Kentucky, Yaziri Gonzalez

Theses and Dissertations--Entomology

Phytophagous stink bugs (Hemiptera: Pentatomidae) are pests of significant importance to soybean, Glycine max (L.), because they can cause severe losses in seed quality, ultimately affecting yield. Damage to soybean is caused through a process called extra-oral digestion. This occurs when the adults and nymphs of stink bugs pierce plant tissues with their mandibular and maxillary stylets, insert digestive enzymes, break down tissue, and extract the digested plant fluid. Three endemic stink bug species of North America are present in Kentucky: green stink bug (Chinavia hilaris), brown stink bugs (Euschistus species complex), and red-shouldered stink bug (Thyanta custator) …

Epigenetic Regulation Of Hormone Action In The Red Flour Beetle, Tribolium Castaneum (Herbst), Smitha George

Theses and Dissertations--Entomology

Hormones are the chemical communication signaling molecules released into the body fluid to stimulate target cells of multicellular organisms. Two major hormones, ecdysteroids (20-hydroxyecdysone, 20E) and juvenile hormones (JH), regulate a wide variety of physiological and developmental processes in insects. Therefore, hormones have been extensively studied and are attractive targets for the development of target-specific insect control methods. Recent studies suggest that epigenetics adds another layer of regulation to explain multiple functions of the same circulating hormone in different tissues and at various time points. In my dissertation, I focused on a major post-translational modification, ‘acetylation,’ to elucidate the epigenetic …

Evaluation Of Kentucky Grown Soft Red Winter Wheat With Sensory Evaluation For Bread-Making Capabilities And Quality, Asa Conkwright Iii

Theses and Dissertations--Nutrition and Food Systems

Soft red winter (SRW) wheat is a type of wheat that is best suited to grow in Kentucky. However, due to its low protein content, it is an undesirable flour for bread and is usually used for cakes, cookies, crackers, and pastries. This is problematic because this limits the ability for commercial bakers to have a local source of flour, forcing them to purchase from sources outside the state. In doing so, bakers are sacrificing freshness and quality. It also removes the opportunity to keep profits in Kentucky, contributing to the state’s economy. The purpose of this study was to …

Improving Kentucky's Winter Wheat And Double Crop Soybean Rotation, Katherine Susan Rod

Theses and Dissertations--Plant and Soil Sciences

The winter wheat double crop soybean rotation is an economically viable rotation for Kentucky farmers. Recent decreases in commodity prices has warranted the need to evaluate intensive management practices that can increase yields and profitability in this crop rotation. There were three goals of this dissertation: 1.) identify management practices that would decrease deoxynivalenol (DON) in harvested wheat grain and increase wheat heading and anthesis uniformity, 2.) evaluate double crop soybean planting timing and identify intensive management practices to increase seed yield, and 3.) determine the profitability of these management options. These studies were conducted in Princeton KY between 2016 …

Extracting Secondary Metabolites From Bacterial Endophytes To Suppress Or Promote Sweet Sorghum And Weeds, Mohammad R. Alsabri

Theses and Dissertations--Plant and Soil Sciences

Endophytic bacteria are ubiquitous in agricultural settings and have the potential to drastically affect plant growth both positively and negatively. These complex relationships play a key role in plant nutrition and are therefore of great interest to the agricultural community and beyond. With my dissertation work, I have had the opportunity to examine the relationship between endophytic bacteria and plants in various ways. The first part of my dissertation investigated how the microbial diversity found in soil affects the below- and above-ground traits of Sorghum bicolor. In the second section, I focused on a particular strain of bacteria that …

Arthropod Resistant Tomatoes: Screening Tools, Yield And Nutritional Quality Of Interspecific Hybrids, Mohammad Hasan Salman Ali Dawood

Theses and Dissertations--Plant and Soil Sciences

Tomato (Solanum lycopersicum) is one of the most economically important vegetable crops grown around globe but is a host for numerous pests and pathogens. In the future, tomato breeders will have to focus on increasing fruit quantity and on enhancing pest resistance. Many accessions of the wild relative of tomato, S. habrochaites display high levels of resistance towards arthropods such as spider mites. The presence of the sesquiterpene hydrocarbon, 7-epi-zingiberene, found in S. habrochaites type IV trichomes has been associated with arthropod resistance. However, the presence of other compounds in its trichome secretions may also be related …

Cover Crops And Cover Crop Mixes: Stratification Of Biological Effects, Landon M. Gibbs

Theses and Dissertations--Plant and Soil Sciences

The potential nutrient cycling benefits from legumes (e.g. N₂-fixation) and the high biomass potential of cereal rye are well known. Further studies are warranted to evaluate bi-culture mixtures and their effects on soil nutrient stratification and microbial enzyme activity because these two properties may be differently expressed (enhanced) by legume/grass mixes. The objectives of this study were: (1) show different cover crops and cover crop mixes containing grasses and legumes differentially stratify carbon and N; (2) show the change in microbial enzyme activity in soils planted with individual cover crops relative to cover crop mixes; 3) determine the …

Using Biology To Better Inform Marestail [Conyza Canadensis (L.) Cronq.] Management, Ryan James Collins

Theses and Dissertations--Plant and Soil Sciences

The importance of sustainable weed management practices continues to grow as farmers are increasingly faced with herbicide resistant weed populations. Marestail (Conyza canadensis), also known as horseweed, is a problematic weed in soybean cropping systems that has developed resistance to multiple herbicide modes of action. A two year study was conducted in Lexington, KY, examining timing patterns of marestail emergence and different integrated weed management strategies for marestail prior to no-till soybean. Treatments contained fall and spring applied herbicides with different levels of residual activities, cover crops and combinations of the two. Additionally, yields and partial budget net …