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Theses/Dissertations

2013

Agriculture

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Full-Text Articles in Life Sciences

Sustainable Management Of The Main Two Maltese Indigenous Grape Varieties For Winemaking, Jonathan Falzon Dec 2013

Sustainable Management Of The Main Two Maltese Indigenous Grape Varieties For Winemaking, Jonathan Falzon

Masters Theses

Ġellewża and Girgentina, the main two Maltese indigenous grape varieties that are used for winemaking, are grown in small parcels of land with an average size just over 0.1 ha. Policies and regulations that influence the sector have been set up and this increased the need for studies to understand the current management practices and how can they be more sustainable. Through interviews with 30 growers of the indigenous grape varieties it was found that most vines are trained as bush vines and cane pruned with 2 or 3 canes with about 5 to 10 buds in each. Nutrition ...


Land Grabs And Implications On Food Sovereignty And Social Justice In Senegal, Joanna Lafrancesca Dec 2013

Land Grabs And Implications On Food Sovereignty And Social Justice In Senegal, Joanna Lafrancesca

Master's Theses

This thesis focuses on the case study of Senegal to examine the implications of large- scale land acquisitions on the livelihoods of small-scale farmers. I investigate the diverse perspectives of market enthusiasts, human rights organizations, peasants, the state, and international financial organizations on large-scale land acquisitions. Based on primary research, I argue that the state of Senegal plays an active role in permitting “land grabs” and that they pose a threat to food sovereignty among Senegalese host communities. Lastly, I argue there needs to be a broader understanding of long-term consequences and risks to insure social justice in areas affected ...


Animal Welfare Around The World: Examining The Role The Economy Has On Animal Welfare, Olivia J. Thornton Dec 2013

Animal Welfare Around The World: Examining The Role The Economy Has On Animal Welfare, Olivia J. Thornton

Chancellor’s Honors Program Projects

No abstract provided.


Northwest Arkansas Consumer Perceptions Of Poultry Production, Stuart Estes Dec 2013

Northwest Arkansas Consumer Perceptions Of Poultry Production, Stuart Estes

Agricultural Education, Communications and Technology Undergraduate Honors Theses

Poultry production holds an important place in Arkansas economically and as a food source. The importance of poultry production ultimately hinges on the demands of the consumers and the perceptions that drive their purchases. With this in mind, this study surveyed consumers to assess their perceptions of poultry production in Arkansas. The instrument used to survey consumers was created by the researcher and an expert committee at the University of Arkansas. Consumers were interviewed through direct communication at grocery stores in northwest Arkansas. Data gathered from the study were analyzed for descriptive and correlational statistics. Data showed that consumers were ...


Sugar And Rice Trade Between The United States And Cuba Trade Potential And Welfare Analysis, Fabian Bloechl Dec 2013

Sugar And Rice Trade Between The United States And Cuba Trade Potential And Welfare Analysis, Fabian Bloechl

Theses and Dissertations

After the resignation of President Fidel Castro and forty-five years of the U.S.-trade embargo, the political environment between Cuba and the United States is expected to change. With the Trade Sanction Reform and Export Enhancement Act in 2000, trade sanctions were eased for a while. Future trade between both countries would increase the welfare in both countries. This Thesis has the approach to look at the impacts on the commodities of rice and sugar, and the trade sanctions between the United States and Cuba.

Cuba is a net importer of its food supply; therefore, agriculture and food trade ...


Preservice Candidates' Rating Of Effectiveness In Agricultural Education Through Structured Communication With Cooperating Teachers, Christopher Lee Hunt Dec 2013

Preservice Candidates' Rating Of Effectiveness In Agricultural Education Through Structured Communication With Cooperating Teachers, Christopher Lee Hunt

Theses and Dissertations

The relationship between cooperating teacher and student has been found as one of the key elements that affect the overall teaching efficacy of student teachers and their decision to enter the teaching field after graduation (Edgar, 2007; Edgar, Roberts, & Murphy, 2011,2008; Kasperbauer et al., 2007a; Roberts, Greiman, Murphy, Ricketts, Harlin, & Briers 2009; Roberts, Harlin, & Briers, 2007, Roberts, Harlin, & Ricketts, 2006; Roberts Mowen, Edgar, Harlin & Briers, 2007, Stripling, Ricketts, Roberts & Harlin, 2008; Wolf, 2011; Wolf et al., 2010). Therefore, determining impacts towards teaching efficacy during the student teaching experience could play a vital role in future teachers' success. The purpose of this study was to assess teaching efficacy and the relationship between student teacher and cooperating teacher through ...


Forage And Biomass Dual-Purpose Harvest System Using Native Warm-Season Grasses, David Weston Mcintosh Dec 2013

Forage And Biomass Dual-Purpose Harvest System Using Native Warm-Season Grasses, David Weston Mcintosh

Masters Theses

There has been increasing interest in utilizing native warm-season grasses (NWSGs), especially switchgrass, as a biomass feedstock for cellulosic ethanol production. Millions of hectares of crop and pasture in the mid-South are forecast to potentially be planted with switchgrass for biomass feedstock production. This could have a substantial impact on the region’s cattle industry, reducing forage production hectares. This study was conducted to determine the effect of early season harvest timing on forage and biomass of NWSGs designed for use in cellulosic ethanol production. The over-all hypothesis was to determine if an early forage harvest can be included in ...


Evaluating Economic Impacts Of Switchgrass Harvest Time, Nathanial Elsworth Cahill Dec 2013

Evaluating Economic Impacts Of Switchgrass Harvest Time, Nathanial Elsworth Cahill

Theses and Dissertations

This thesis deals with cost of production for cellulosic energy crops of switchgrass, miscanthus, and energy sorghum. The first chapter explains the rationale for development of decision support software called Energy Crop Analysis & Planning (ENCAP) and Switchgrass Harvest Date, Yield, Nutrient Removal Estimator (SHYNE). The second chapter examines harvest date implications on yield, nutrient removal, opportunity cost of modified sale dates, and post-harvest storage losses. This harvest date analysis leads to a profit maximizing harvest date from the perspective of the producer. While this harvest date may be optimal for the producer, biorefineries may be interested in sourcing switchgrass earlier ...


Risk Return Of Farmer-Elevator Contracts For Soybeans And Corn In Arkansas, Marei Undine Houpert Dec 2013

Risk Return Of Farmer-Elevator Contracts For Soybeans And Corn In Arkansas, Marei Undine Houpert

Theses and Dissertations

In Arkansas the contribution of Agriculture to the states GDP is comparatively high. To help farmer's return risk the grain industry developed several marketing tools to support farmers. Literature in this research field finds different results for different locations, commodities, marketing tools and marketing years. As Agriculture in Arkansas is important for its economy this study focuses on soybeans and corn produced in the fertile north-eastern area of Arkansas that uses Memphis Tennessee as a spot market palace. The examined marketing tools are pre-harvest futures hedges and forward contracts as well as post-harvest storage strategies and minimum price contracts ...


Producers Willingness To Adopt A Prescribed Grazing System East Of The 100th Meridian, Caroline Elizabeth Holt Dec 2013

Producers Willingness To Adopt A Prescribed Grazing System East Of The 100th Meridian, Caroline Elizabeth Holt

Masters Theses

With the climate change concerns facing the United States, the contributions of the beef industry to greenhouse gasses are difficult to overlook. The agriculture industry is estimated to be the largest producer of methane emissions in the United States, and within agriculture, livestock are the largest contributor with cattle producing 73 percent of the methane emissions from all livestock (Johnson and Johnson 1995).

This thesis focuses on factors influencing beef cattle producers’ east of the 100th meridian interest in adopting prescribed grazing; including how a government cost share system could enhance adoption. Information was obtained for the study through a ...


Hydrogeology Of The Little River Animal Agriculture Environmental Research Unit And Impacts Of Dairy Operations On Groundwater, Robert Wesley Hunter Dec 2013

Hydrogeology Of The Little River Animal Agriculture Environmental Research Unit And Impacts Of Dairy Operations On Groundwater, Robert Wesley Hunter

Masters Theses

This thesis describes the development of an integrated hydrogeologic/hydrologic site assessment and groundwater/surface water quality monitoring program at the University of Tennessee – Little River Dairy Farm, located near Townsend, TN. Hydrologic/hydrogeologic investigations of streams and groundwater at the site have been underway for more than 5 years, and these are expected to provide background data for assessing impacts of dairy wastes. The lower half of the ~180 ha site consists of low-relief fields used for row crops, which are underlain by 4 – 9 m of alluvial deposits on top of black shale or limestone that include sinkhole ...


Illinois Secondary Agriculture Teachers' Perception Of Critical Development Of Undergraduate Experiences, Alicia Jo Gullidge Nov 2013

Illinois Secondary Agriculture Teachers' Perception Of Critical Development Of Undergraduate Experiences, Alicia Jo Gullidge

Theses and Dissertations

The goal of this study is to provide the leadership of Illinois Agricultural Education with an understanding of what practicing teachers feel were the most important experiences in their pre-service teacher education program that ensured they were prepared for the classroom. This information can be used to streamline the teacher education programs and eliminate experiences that are perceived to be less relevant to preparing teachers. It is believed that this will assist with ongoing efforts dealing with recruitment and retention.

The area's that will be addressed in this survey will be demographics and pre-service events that future agriculture teachers ...


Improving The Efficiency Of Fall Applied N With Cover Crops, Corey Lacey Nov 2013

Improving The Efficiency Of Fall Applied N With Cover Crops, Corey Lacey

Theses and Dissertations

Nitrate loss studies in Midwestern tile-drained fields have found that fall applied nitrogen (N) resulted in elevated nitrate concentrations in tile water during both the corn and soybean year of a 2 year rotation. The effectiveness of cover crops to reduce nitrate leaching when N is spring applied has been well demonstrated, however there is a dearth of knowledge on the ability of cover crops to reduce nitrate leaching in a system where N is fall applied. Thus, the objectives of this research were to (i) investigate the efficacy of winter cover crops to reduce nitrate leaching from fall applied ...


Heterologous Production And Characterization Of Cell Wall Degrading Enzymes Using Plants As A Bioreactor, Eridan Orlando Rodrigues Pereira Oct 2013

Heterologous Production And Characterization Of Cell Wall Degrading Enzymes Using Plants As A Bioreactor, Eridan Orlando Rodrigues Pereira

Electronic Thesis and Dissertation Repository

Plants are wonderful living organisms. They are able to store solar energy into carbohydrates by fixing CO2 through photosynthesis which can be subsequently harvested and used for fuel production. However, one of the major limitations for transforming these carbohydrates into liquid fuels is the recalcitrance of the plant cell wall. Although microorganisms have evolved a series of cell wall degrading enzymes to harvest efficiently this energy and are considered the main source of these biocatalysts, harnessing these microorganisms for the production of enzymes is a costly process and a major factor limiting the commercialization of lignocellulosic biomass-to-ethanol processes. The ...


Uncovering The Molecular Link Between Mir156.Spl15 And Carotenoid Accumulation In Arabidopsis, Davood Emami Meybodi Oct 2013

Uncovering The Molecular Link Between Mir156.Spl15 And Carotenoid Accumulation In Arabidopsis, Davood Emami Meybodi

Electronic Thesis and Dissertation Repository

Carotenoid Cleavage Dioxygenases (CCDs) are an enzyme family that cleaves specific double bonds in carotenoids. MicroR156 in Arabidopsis regulates a network of genes by repressing 10 SPL genes, among which, SPL15 was found to regulate shoot branching and carotenoid accumulation. The expression of CCD1, CCD4, CCD7, CCD8, NCED2, NCED3, NCED5, NCED6, NCED9 and SPL15 was evaluated in siliques at 10 days post anthesis and in 10-day-old roots in Arabidopsis wild type, sk156 (miR156 overexpression mutant), RS105 (miR156 overexpression line), spl15 (SPL15 knockout mutant) and two 35S:SPL15 lines. Results showed that most of CCD/NCED genes were affected ...


Spatial Analysis Of Climate And Winegrape Production In Winegrape Growing Regions Of Oregon, United States Of America, Willow Devin Campbell Oct 2013

Spatial Analysis Of Climate And Winegrape Production In Winegrape Growing Regions Of Oregon, United States Of America, Willow Devin Campbell

Dissertations and Theses

American Viticultural Areas (AVAs) are susceptible to small variations in climate and microclimates and are found within a narrow latitudinal range of prime climate conditions. These AVAs are geographically determined based on the best soil, climate, precipitation and temperature combinations for specific winegrape regions. As climate change continues to alter the local weather and the greater climate region of the Western United States, winegrape growing regions in Oregon are being affected. In an effort to determine what the pattern of change is, and compare previous studies of climate change using climate indices, a comparative study based in part on prior ...


Functional Characterization Of Metallothioneins In Arabidopsis And Barley, Nimnara Yookongkaew Oct 2013

Functional Characterization Of Metallothioneins In Arabidopsis And Barley, Nimnara Yookongkaew

Open Access Dissertations

Metalothioneins (MTs) are metal binding proteins that can bind metals such as Cu, Zn, and Cd but the functions of MTs in plants are largely unknown. To understand the function of MTs in Arabidopsis, T-DNA insertion mutants lacking 4 MT genes including MT1a, MT2a, MT2b and MT3 were developed. The quadruple mutant (mt1a/mt2a/mt2b/mt3) showed no visible phenotype under standard growth conditions. However, it accumulated higher Cu in leaves compared to wild type but lower Cu in seeds. Further analysis showed that triple mutants lacking both MT1a and MT2b, which are highly expressed in vascular tissues, had similar ...


Welfare Impacts Of False Codling Moth Threatening California Oranges, Azza Mohamed Kamal Ahmed Mohamed Oct 2013

Welfare Impacts Of False Codling Moth Threatening California Oranges, Azza Mohamed Kamal Ahmed Mohamed

Open Access Dissertations

Welfare impacts of alternative pest management strategies of False Codling Moth (FCM) threatening California's oranges are examined. Different economic agents along the supply chain of fresh oranges and orange products in the United States are considered, including consumers, retailers, wholesalers, and growers. A partial equilibrium dynamic framework that accounts for supply response from the other US orange producing states is developed. Data for supply shocks (orange yield losses and control costs) are obtained from the Animal and Plant Health Inspection Service of the United States Department of Agriculture (APHIS).

FCM is not presently in the United States. If introduced ...


Impacts And Feasibility Of The Us And The Eu Sustainability Criteria On Existing Land-Use Practices, Krissana Treesilvattanakul Oct 2013

Impacts And Feasibility Of The Us And The Eu Sustainability Criteria On Existing Land-Use Practices, Krissana Treesilvattanakul

Open Access Dissertations

Several studies have examined the land use and economic consequences of national and multi-national biofuel policies. They explored the impacts of biofuels mandates mainly based on the quantitative biofuel targets. However, the recently updated renewable policies of the United States and the European Union, which are the US Renewable Fuel Standard (RFS) and EU Directive 2009/28 of the Renewable Energy Directive (RED) both place restrictions on land that can be used to produce biofuel, and these restrictions are generally known as sustainability criteria. This research aims to determine to what extent sustainability criteria are actually binding; that is, would ...


Management Of Potato Leafhopper And Maple Spider Mite On Nursery Grown Maples, Julia Prado Beltran Oct 2013

Management Of Potato Leafhopper And Maple Spider Mite On Nursery Grown Maples, Julia Prado Beltran

Open Access Dissertations

Potato leafhopper Empoasca fabae (Harris) (Homoptera: Cicadellidae) and maple spider mite Oligonychus aceris (Shimer) (Acarina: Tetranychidae) are important pests of maple trees. Investigations determined how insecticide use and fertilization impacted the abundance of E. fabae and O. aceris on `Red Sunset' red maple and `Autumn Blaze' Freeman maples. Bifenthrin applications directed against leafhoppers reduced damage to both cultivars, but increased O. aceris on Autumn Blaze. Using a threshold of one leafhopper per branch to trigger pesticide applications protected Red Sunset maples from leafhopper injury. It also prevented outbreaks of O. aceris on Autumn Blaze because few trees reached this density ...


Three Essays On The Interaction Between Global Trade And Greenhouse Gas Mitigation Agreements, Zeynep Burcu Irfanoglu Oct 2013

Three Essays On The Interaction Between Global Trade And Greenhouse Gas Mitigation Agreements, Zeynep Burcu Irfanoglu

Open Access Dissertations

The role of trade sanctions in enforcing greenhouse gas mitigation agreements is the fundamental theme of the three essays comprising this dissertation. All three essays employ a multi-sector, multi-region computable general equilibrium model, GTAP-AEZ-GHG, documented in Golub et al. (2009) to investigate how the United States can use trade sanctions as an enforcement mechanism in a global greenhouse gas (GHG) mitigation agreement. The focus is placed on inducing China to comply with the global agreement.

The first essay contributes to the body of knowledge on global GHG emissions mitigation agreements by investigating the range of emission taxes that can be ...


The Role Of Soil Microorganisms In The Resistance Of Giant Ragweed, Horseweed, And Common Lambsquarters To Glyphosate, Jessica Renee Schafer-Bugg Oct 2013

The Role Of Soil Microorganisms In The Resistance Of Giant Ragweed, Horseweed, And Common Lambsquarters To Glyphosate, Jessica Renee Schafer-Bugg

Open Access Dissertations

Continuous glyphosate use has contributed to an increasing number of problematic glyphosate-resistant (GR) weeds. The mechanism of resistance in many GR weeds is poorly understood, in part, due to a poor understanding of how exactly glyphosate kills a plant. In previous research, the efficacy of glyphosate was demonstrated to be strongly influenced by root invading soil-borne microorganisms. However, this interaction among plants, glyphosate, and soil microorganisms has only been studied in a number of crop plants, but not in weed species. This is surprising since the soil biotic environment has a strong impact on the activity of this important herbicide ...


Environmental Tradeoffs In Bioenergy Production And Agricultural Practices, Alicia Lynn English Oct 2013

Environmental Tradeoffs In Bioenergy Production And Agricultural Practices, Alicia Lynn English

Open Access Dissertations

The focus of this dissertation is the environmental tradeoffs of stover removal within the Corn Belt. The environmental tradeoffs considered are mainly concerned with managing soil erosion and soil quality. The analysis layers soil characteristics, management strategies and per acre costs using an integrated RUSLE2/WEPS model and an economic optimization model to illuminate a lower bound supply response. Different assumptions were tested in regards to sustainability, prices, and market integration for five states and 18,760 soil types throughout the Corn Belt. Sustainability was defined to limit soil erosion from wind and water to 5 tons/acre/year and ...


Genes With Physiological Roles In Callipyge Muscle Hypertrophy, Hui Yu Oct 2013

Genes With Physiological Roles In Callipyge Muscle Hypertrophy, Hui Yu

Open Access Dissertations

Callipyge sheep is an excellent model to study genes regulation in muscle growth since the up-regulation of DLK1 and/or RTL1 results in extreme postnatal muscle hypertrophy in loin and hindquarters. DLK1 and/or RTL1 are the primary inducers of muscle hypertrophy due to the inheritance model for the callipyge phenotype. The overall aim of this dissertation is to study the physiological pathways responding to the up-regulation of DLK1 and / or RTL1 in the hypertrophied muscles. Microarray analysis of gene expression identified 375 genes that were differentially expressed in callipyge semimembranosus. Twenty-five transcripts were further verified by quantitative PCR in ...


The Effects Of Planting Techniques On Maize Grain Yield And Silage Production, Tyler D. Kaufman Sep 2013

The Effects Of Planting Techniques On Maize Grain Yield And Silage Production, Tyler D. Kaufman

Theses and Dissertations

This thesis is a comprehensive analysis of the effects of seed orientation, row direction and planting population on grain yield, kernel composition, and silage yield and composition. Producers are striving to increase profit by efficiently using their available land area to maximize crop production. However, little research is available testing the effect of seed orientation on grain or silage production. Quantifying the impacts of seed orientation and row direction on grain and silage is essential for maximum crop production. Dissemination of the results should benefit grain and silage producer.

Two experiments were conducted to evaluate the effects of manipulating seed ...


Use Of Flame Cultivation As A Nonchemical Weed Control In Cranberry Cultivation, Katherine M. Ghantous Sep 2013

Use Of Flame Cultivation As A Nonchemical Weed Control In Cranberry Cultivation, Katherine M. Ghantous

Open Access Dissertations

Cranberry (Vaccinium macrocarpon Ait.) is a woody perennial crop that can remain productive for decades. Competition for resources between cranberries and weeds can depress cranberry farm yields, resulting in large annual crop losses. Renewed interest in reducing chemical inputs into cranberry systems has provided the motivation to evaluate methods, such as flame cultivation (FC), as potential nonchemical options for weed control. Also known as thermal weeding, FC exposes plants to brief periods of high temperature that causes the water in the plant tissue to expand rapidly, rupturing plant cells and leading to necrosis. Various FC methods have been used successfully ...


The History Of Trial Gardens, Hallie Schmidt Sep 2013

The History Of Trial Gardens, Hallie Schmidt

Horticulture and Crop Science

Essay explores the history of home gardening and seed industry in America and the conditions that led to the development of the All-America Selections.


Modeling Leafhopper Populations And Their Role In Transmitting Plant Diseases., Ji Ruan Aug 2013

Modeling Leafhopper Populations And Their Role In Transmitting Plant Diseases., Ji Ruan

Electronic Thesis and Dissertation Repository

This M.Sc. thesis focuses on the interactions between crops and leafhoppers.

Firstly, a general delay differential equations system is proposed, based on the infection age structure, to investigate disease dynamics when disease latencies are considered. To further the understanding on the subject, a specific model is then introduced. The basic reproduction numbers $\cR_0$ and $\cR_1$ are identified and their threshold properties are discussed. When $\cR_0 < 1$, the insect-free equilibrium is globally asymptotically stable. When $\cR_0 > 1$ and $\cR_1 < 1$, the disease-free equilibrium exists and is locally asymptotically stable. When $\cR_1>1$, the disease will persist.

Secondly, we derive another general delay differential equations system to examine how different life stages of leafhoppers affect crops. The basic reproduction numbers $\cR_0$ is determined ...


Agriculture Honors Programs In Aplu Member Institutions, Sable A. Sellick Aug 2013

Agriculture Honors Programs In Aplu Member Institutions, Sable A. Sellick

Agricultural Education, Communications and Technology Undergraduate Honors Theses

In order to continue to feed and clothe nearly 9 billion people by the year 2050, there is a definite need for innovative agriculturalists to contribute to the field of agricultural research. Land-grant and public universities, established over 100 years ago with a devotion to agricultural research, have begun to develop “honors programs” in order to attract the best and brightest students away from private universities and to their campuses. This study sought to discover how common agricultural honors programs were and what characteristics they shared via a survey administered over the internet and distributed to a database of contacts ...


A Roadmap To Mindful Consumption Through Informative Labeling Practices: The Effects Of Sustainability Disclosure Formats On Consumer Product Evaluations, Yoon-Na Cho Aug 2013

A Roadmap To Mindful Consumption Through Informative Labeling Practices: The Effects Of Sustainability Disclosure Formats On Consumer Product Evaluations, Yoon-Na Cho

Theses and Dissertations

Despite the interest of consumers in sustainable and environmentally friendly products, only a limited number of studies have focused on sustainability level disclosures for consumer packaged goods. The general overarching purpose of this dissertation is to extend the internal reference point and information processing literatures to better understand how consumers will process sustainability disclosures. Applying the theoretical lens of assimilation bias in conjunction with self-enhancement offers an important extension to prior work. Across two retail lab studies and four online experiments, I demonstrate that the perceived sustainability utility (i.e., the difference between a specific brand's level of sustainability ...