Digital Commons Network^™

Switchgrass Extractives Have Potential As A Value-Added Antimicrobial Against Plant Pathogens And Foodborne Pathogens, Alexander Ian Bruce

Masters Theses

Panicum virgatum (switchgrass), a perennial grass native to North America, is a leading biomass feedstock candidate for the manufacture of cellulosic ethanol. Switchgrass is considered a viable option for biofuel production due to its cheap production cost and ability to grow on marginal land. Biofuel derived from switchgrass has been shown to be very energy efficient, producing 540% more renewable energy versus nonrenewable energy expended. Switchgrass-derived biofuel is also estimated to have greenhouse gas emissions that are 94% lower than emissions from gasoline (Schmer et al 2008). Biofuels are created through biochemical processes that utilize various enzymes and microorganisms for …

Reasons Youth Choose Or Do Not Choose To Be Involved In 4-H Livestock Projects In Tennessee, Leigh Erin Fuson

Masters Theses

The purpose of this study was to find reasons youth choose or do not choose to be involved in 4-H livestock projects. Livestock projects are an important part of 4-H youth development because they teach life skills like responsibility and hard work. However, many youth are unable to participate or do not have the interest. This study sought to discover what motivates some youth to become involved in a livestock project and why others do not.

Focus groups were used as the data collection tool. Two groups of youth livestock participants and two groups of non-livestock participants were utilized. Themes …

Assessing Tennessee Livestock Producers' Awareness, Attitudes And Perceptions Of Right-Of-Way Hay Harvesting, Sarah Joy Maccaro

Masters Theses

In the state of Tennessee, statute 54-5-134, cutting hay along controlled access highway right-of-way, gives Tennessee agriculturalists the right to harvest hay along interstate medians and shoulders. Current maintenance is contracted out to private mowing companies and paid for by Tennessee taxpayers. Relatively few studies have been published on the topic of right-of-way hay harvesting, so this study was preliminary in nature. Through a questionnaire, this study sought to assess Hickman, Dickson, Williamson, Wilson and Rutherford county livestock producers’ current awareness, attitudes, and barriers concerning right-of-way hay harvesting as well as to conduct economic impact analyses to determine producers’ willingness …

Soil-Water Transport Of A Seed Coated Neonicotinoid Pesticide In Soybean/Maize Cultivation Systems, Geoffrey Nathaniel Duesterbeck

Masters Theses

The current decline of the honey bee (Apis mellifera L.) and other beneficial pollinator species is well documented. Several causes have been cited in this decline including: pathogens, pests, nutrition, and pesticide exposure. Since the advent of the neonicotinoid family of pesticides in the 1990’s an increase in honey bee colony loss has been observed. Neonicotinoid pesticides are commonly applied as a seed treatment to cotton, soybean and maize row crops. As the seed germinates, it absorbs the pesticide from the coating then spreads systemically throughout the entire plant. However, a large portion of the seed coating may stay …

Influence Of Application Technology On Foliar Fungicide Efficacy On Cercospora Sojina Infected Soybean, Shawn Alan Butler

Masters Theses

Due to the constant concern with off-target contamination and application technology requirements associated with future herbicide-tolerant crops, the use of drift-reduction nozzle technology (DRT) may increase. The primary objective of this research was to evaluate the effects of coarse droplets generated by drift-reduction nozzles on foliar fungicide efficacy and residual in soybean infected by frogeye leaf spot caused by Cercospora sojina. No differences in disease control, soybean yield, spray retention, and residual when applying Quadris Top SB, a premix of azoxystrobin and difenoconazole, using nozzles that produce either a medium or ultra coarse droplet spectrum were determined.

Due to …

Regional Dynamic Price Relationships Of Distillers Dried Grains In U.S. Feed Markets, Matthew Fulton Johnson

Masters Theses

Distillers dried grains with solubles (DDGS) is now a mainstream substitute in U.S. animal feed rations. DDGS is rich in fat and protein content and serves as a competitive feed source in livestock markets. The objective of this study is to identify dynamic price relationships among DDGS, corn, soybean meal, and livestock outputs in context of specific livestock sectors and their geographic location. Four locations associated with a predominant livestock sector are selected for analysis by measuring density and relative proportion of a livestock sector’s grain consumption at the county level. A vector error correction model is applied to post-mandate …

Retained Ownership Profitability Of Beef Cattle Originating In Tennessee, Minfeng Tang

Masters Theses

Retained ownership is a marketing strategy that can be used by cow-calf operators to benefit from the potential increase in fed cattle prices. We analyze the profitability of retained cattle ownership from 2005 to 2015 for cow-calf producers in Tennessee. We also determine the impact of steer/heifer characteristics (e.g., average daily gain, feed conversion) and producer choice decisions (e.g., placement weight, placement season, days on feed) on retained ownership profitability. Data on 2,953 head of cattle originating in Tennessee and finished in Iowa using a retained ownership strategy were collected. A mixed regression model explaining profitability was estimated with fixed …

Opportunities In Sustainability: Maize Seeders For The Developing World And Alternative Fertilizers In The United States, Rebecca Mattingly Harman

Masters Theses

Sustainable agricultural systems are needed for both large and small-scale farmers the world over. Central to the sustainability of these systems is the availability of cheap and effective seeders for smallholder farmers and effective utilization of less energy intensive nitrogen sources. In the first two chapters, this thesis considers maize seeders for smallholder use in a Conservation Agriculture system. To sustain the smallholder sector, soil fertility and soil erosion must be addressed and a Conservation Agriculture model seeks to improve soil conditions in agriculture. The technologies available to smallholder farmers, though, need to be tested in a no-till system before …

Tennessee Consumers’ Willingness To Pay For Tennessee Wine, Connie Nichols Everett

Masters Theses

With a large and growing market, grape production and wineries are emerging in areas of the United States that have not been previously recognized as wine producing states. Tennessee is an example of such a state that has a history of limited wine grape production, but has recently seen a growing interest in state produced wines by consumers. However, there is no information regarding whether a Tennessee produced and labeled wine would impact consumers’ purchases and willingness-to-pay (WTP) for wine. The objective of this research is to determine the factors influencing consumers’ purchases of Tennessee labeled wine and to estimate …

Evaluation Of Fungicide Efficacy Against Cercospora Sojina And Selection For Qoi-Fungicide Resistance In Soybean, Alicia Mercedes Cochran

Masters Theses

Frogeye leaf spot (FLS) of soybean is caused by Cercospora sojina. In 2010, resistance to the quinone outside inhibitor (QoI) fungicides was reported. Since then, evaluating FLS for QoI-resistance has been of particular interest in Tennessee and other soybean-producing states. In order to determine alternative fungicide options, fungicides with solo and combination mode of action were tested in 2013-2014. The objectives were,1) to evaluate fungicide efficacy for disease control and yield protection, and 2) evaluate selection pressure for QoI-resistance. Treatments included the following fungicide groups: QoI, DMI, MBC, Chlorothalonil, QoI+DMI, SDHI+QoI, SDHI+QoI+DMI, and DMI+MBC. QoI and Chlorothalonil treatments failed …

Evaluation Of Agronomic, Seed Quality Traits, And Transcript Abundance In Conventional High Oleic Soybeans With Mutant Fad2-1a And Fad2-1b Genes, Lauren Kathryn Richardson

Masters Theses

Two soybean omega-6 fatty acid desaturase genes [FAD2-1A and FAD2- 1B] are responsible for converting oleic acid into linoleic acid (Okuley et al., 1994). Plant introductions [PI] 603452 and 283327 have naturally occurring mutations in FAD2-1A and FAD2-1B, respectively, which hinder the conversion of oleic acid to polyunsaturated fatty acids. The end result is more functional soybean oil with exceptionally high levels of oleic acid. The homozygous alleles of FAD2-1A and FAD2-1B were combined in a BC₃F_2:4 [backcross three, second filial generation selected, advanced to the fourth filial generation] population of forty-eight lines and were evaluated in …

Impacts Of Biofumigation And Anaerobic Soil Disinfestation On Strawberry Production, Jennifer Renee’ Wheeler

Masters Theses

Due to the phase-out of methyl bromide, there is a need for alternative, nonchemical fumigation treatments in strawberry production. Anaerobic soil disinfestation and biofumigation are two non-chemical methods for controlling soilborne plant pathogens of strawberry. This study was designed to observe strawberry fruit nutrition and soil volatiles of a strawberry field being treated with biofumigation treatments, anaerobic soil disinfestation treatments, and a combination of the two alternative methods. A trial was conducted with 11 pre-plant soil-incorporated treatments arranged in a randomized complete block design with 6 rows (blocks). Biofumigation treatments consisted of deactivated mustard meal, deoiled mustard meal, mustard pellets, …

4-H Wildlife Habitat Education Program: A Qualitative Study On Career Exploration, Ronnie Lee Cowan

Masters Theses

There are documented studies on the Wildlife Habitat Education Program (WHEP) that relate to building life skills of participants. However, no literature was found that measured the perceptions of the participants towards a career in wildlife after participating in WHEP. To add validity to the program a focus group was conducted at the Tennessee 4-H wildlife judging contest to describe the WHEP participants’ perceptions of careers in wildlife after the completion of the annual program. Focus group participants indicated that participating in WHEP peaked their interest in wildlife and provided an opportunity to experience the importance of natural resource management.

Analysis Of Beef Cattle Producers’ Propensity To Adopt Pasture Management And Prescribed Grazing East Of The 100th Meridian, Kristen Elizabeth Oliver

Masters Theses

Pasture management and grazing practices affect animal productivity, soil carbon storage and soil and water quality. Poor pasture and grazing management practices can cause soil erosion, nitrogen leaching, and runoff into streams and waterways. Based on a survey of cattle farmers east of the 100^th meridian, the following two papers estimate how farm operator, farming operation, and attitudinal variables influence the propensity to use pasture management and prescribed grazing, as well as use of specific pasture management and prescribed grazing practices.

Key findings from the first paper are that individual pasture management and prescribed grazing practices are strong indicators …

Physiological Evaluation And Root Morphological Differences Associated With Novel Drought Tolerant Corn (Zea Mays L.) Hybrids, Austin Gentry Scott

Masters Theses

Corn hybrids designated “drought tolerant” (DT) from three commercial seed companies were evaluated in order to determine the benefit of DT technology in a mid-south environment that may receive adequate but often poorly timed rainfall. Field research was conducted in 2014 and 2015 at Milan, TN where hybrid response to stress was evaluated at two planting dates and in non-irrigated and irrigated environments and greenhouse research was conducted in Jackson, TN to evaluate early season drought to plant physiology and root structure.

In 2014 and 2015, the non-irrigated trials received enough rainfall to create a high yielding environment. Since the …

Long-Term Impacts Of Conservation Management Practices On Soil Carbon Storage, Stability, And Utilization Under Cotton Production In West Tennessee, Candace Brooke Wilson

Masters Theses

Biogeochemical cycling of soil carbon (C) is heavily influenced by conservation agricultural (CA) practices. This study examined SOC stability under three CA practices: reduced nitrogen (N) fertilizer application rate, cover cropping, and zero-tillage implemented for 31 years. Respiration rates measured from a 602-day incubation period were fitted to a double-pool first order exponential model of SOC decomposition. The active [respired] SOC pool showed distinct differences between applications of reduced (34N kg ha^-1 [-1]) and high fertilization rates (101N kg ha^-1) combined with tillage, and suggest that high fertilizer applications with conventional tillage allocated more C into a …

Economic And Environmental Optimization In The Supply Of Switchgrass In Tennessee, Jia Zhong

Masters Theses

The low efficiency of collection, storage and transportation in the switchgrass supply chain has hindered the commercialization of a switchgrass-based biofuel industry, even given its ecological and environmental advantages in carbon sequestrate, soil quality, water use, and pollution pressure. Thus, designing a switchgrass-based supply chain balancing both environmental and economic performance is important to expedite the development of the cellulosic biofuel industry to meet the national energy plan.

The objectives of this study are to 1) determine economic cost and multiple environmental outcomes in feedstock supply chains and 2) identify the relation between the economic and environmental performances. The first …

Population Structure Of Late Blight (Phytophthora Infestans) In Colombia And Ecuador And Downy Mildew (Peronospora Farinosa F. Sp. Spinaciae) On Spinach In Arizona And California, Rebecca Marie Lyon

Masters Theses

In this study, Phytophthora infestans and Peronospora farinosa f. sp. spinaciae populations were analyzed using single nucleotide polymorphisms (SNPs). In Ecuador and Colombia, Phytophthora infestans causes significant damage to potato and tomato and the epidemiology is known to be highly clonal. Our objective was to measure population structure within the context of this clonal epidemiology using both synonymous and nonsynonymous markers. Candidate SNP sites were selected by comparing the draft genomes of the Ecuadorian isolates EC1-3527 and EC1-3626. Genotypes were assessed directly from infected tissue using a targeted sequencing approach. A total of 54 polymorphic sites were assessed in 93 …

Development And Evaluation Of A Cost Effective Plant Growth Media Moisture Sensor And Development Of An Aqueous Data Transmission System For Irrigation Purposes, Steven Michael Pickett

Masters Theses

The ability to accurately monitor and transit the moisture content of soilless growing media in the rooting zone is critical for plant-based research, production of high value crops, and other agricultural production. The focus of this study is the development and evaluation of a cost effective moisture sensor designed to measure the plant-available moisture content of growing media and the development of a aqueous data transmission method for relaying this information back to a central location. While there are currently many commercially available soil moisture sensors on the market, the aim of this research is not to develop a more …

Factors Impacting Ffa Involvement After High School, Danielle Eve-Marie Sanok

Masters Theses

The purpose of this study was to determine the factors that influence FFA members to continue or discontinue with their FFA experience past high school. The specific objectives of this study were to determine the reasons why students discontinue with their FFA experience past high school, determine membership needs from the Collegiate and Alumni FFA Organization and ways to overcome membership attainment barriers.

Data collection methods included three sets of focus groups: (a) one for inactive FFA members, (b) one for current Collegiate FFA members, and (c) one for current and past State Officers. Data was analyzed using the thematic …

Impact Of International Student Teachers On A New South Wales, Australia Community Over Ten Years: A Qualitative Study, Derek Anthony Brawner

Masters Theses

The purpose of this study was to evaluate change in the impact of American agriculture education student teachers on a rural community in New South Wales, Australia over ten years. The study analyzed interviews with ten participants of the American Student Teaching Program in a New South Wales community. The researcher was a student teacher in the New South Wales community for ten weeks and taught agriculture in one of the community’s high schools. Exposure to individuals in the community and also recommendations from the agriculture teachers and principals of the Australian school, which included the principal, deputy principal, one …

The Benefits Of Ffa Membership As Part Of The Three-Circle Model In Agricultural Education, Chelsea Brooke Rose

Masters Theses

The purpose of this study was to understand the benefits of membership in the Future Farmers of America (FFA) student leadership organization among Tennessee FFA members by surveying members attending Camp Clements FFA Leadership Training Camp. The study focused on the fulfillment of FFA members’ basic human needs as defined by Abraham Maslow (1943). The three needs on which this study focused are: love and belonging, self-esteem, and self-actualization (1943). The study found that a majority of FFA members’ three basic human needs are met due to their involvement in career development events, leadership positions, and other FFA activities. Of …

Drd2 And Xkr4: A Genetic Approach To Fescue Toxicosis., Kristine Marie Ely

Masters Theses

Tall fescue (Lolium arundinaceum Schreb) is the most prevalent forage in the Mid-south United States due to its observed hearty nature and ability to withstand heavy grazing. This is due to a symbiotic relationship with an endophytic fungus (Neotyphodium coenophialum). This fungus produces ergot alkaloids, which can bind to many adrenergic, serotonergic, and dopaminergic receptors. One of the primary functions of dopamine is to inhibit prolactin response. Decreased growth, reproduction, lactation, and depressed serum prolactin concentrations are commonly observed in beef cattle grazing endophyte-infected tall fescue. These symptoms are collectively referred to as fescue toxicosis, and …

Carbon Sequestration, Carbon Markets, Technical Efficiency And Maize Production Using Conservation Agriculture In Mozambique, Timoteo Eduardo Simone

Masters Theses

Conservation agriculture practices are a promising sustainable farming system being promoted by various organizations in Mozambique. This thesis analyzes the impact of adoption of conservation agriculture practices on maize production technical efficiency, carbon sequestration and farmer income. The technical efficiency estimation utilizes data from a household survey conducted in Manica and Tete provinces of Mozambique. Soil carbon simulations use information from various sources including the household survey, European Energy markets and local meteorological data from the National Oceanic and Atmospheric Administration.

The second chapter of the thesis evaluates the technical efficiency of maize production using conservation agriculture practices. This section …

Aminocyclopyrachlor Efficacy For Non-Cropland Weed Control, José Javier Vargas Almodóvar

Masters Theses

The production of chemicals for crop protection purposes evolved after World War II with the commercialization of the auxin herbicides 2,4-D and MCPA. Their utility and effectiveness created an interest for North American and European companies to develop and research thousands of agrochemicals available today.

Recently discovered and introduced to the market by DuPont Crop Protection, aminocyclopyrachlor is the first broad spectrum synthetic auxin herbicide in this chemical class, and is structurally similar to the auxin herbicides: aminopyralid, clopyralid and picloram. Aminocyclopyrachlor has activity on broadleaf weed species with limited activity on monocot species. Aminocyclopyrachlor is absorbed via plant roots …

Willingness To Adopt Best Management Practices By Beef Cattle Producers In A Southeastern Tennessee Watershed, Alicia Marie Signore

Masters Theses

Extensive beef cattle farming in the ridge and valley region of East Tennessee suggests that cattle producers could play an important role in improving water quality through the adoption of livestock best management practices (BMPs). This study examines factors influencing willingness to adopt four BMPs—rotational grazing, pasture improvement, stream water crossing, and water tank systems—by beef cattle operations in a southeast Tennessee watershed. Factors examined include farm and farmer characteristics, farmer attitudes, and a hypothetical incentive program encouraging adoption of these practices. Data was collected through a mail survey of 5,150 farmland owners in McMinn, Bradley, and Monroe Counties. Respondents …

Investigating The Effect(S) Of Contrasting Nitrogen (N), Phosphorus (P), And Potassium (K) Fertilizer Rates On Cassava Tuber Yield And Quality And Maize Grain Yield In Southern Africa, Ivan Bernardo Cuvaca

Masters Theses

Fertilizer is a major limiting factor to agriculture in southern Africa (SA). Coupled with this is lack of appropriate fertilizer recommendation rates for high productivity in existing agricultural systems. Field experiments were conducted to determine nitrogen (N), phosphorus (P), and potassium (K) fertilizer rates for high cassava tuber yield and quality for the coastal semiarid Dondo District of Mozambique, and high maize grain yields for both vertisol and inceptisol of Maphutseng in Lesotho. In general, the results showed that cassava tuber yield, cassava tuber quality as measured by tuber starch content, and maize grain yield were significantly increased by fertilizer …

Application Of Botanicals In Poultry Production To Improve Microbiological Quality, Francisco Javier Gonzalez-Gil

Masters Theses

Foodborne illness and outbreaks associated with poultry products are commonly caused by Campylobacter jejuni or Salmonella enterica. These pathogens colonize the bird intestines during rearing, and if processing, handling or cooking is not done properly, contamination and human illness can occur. Probiotics, prebiotics and botanicals are being evaluated as novel feed additives to reduce pathogen colonization and serve as growth promoter additives in poultry production. Some botanicals are of industrial interest because they are natural antimicrobials or possess beneficial effects on human health. In this research, the application of a botanical (yerba mate) and a probiotic were evaluated as …

Value-Added Lignin Based Carbon Fiber From Organosolv Fractionation Of Poplar And Switchgrass, Andreas Attwenger

Masters Theses

Carbon fibers have unique properties that include high strength, low density and excellent chemical and thermal resistance. However, they have a low level of utilization because of their high price; typically around $30/kg for an entry level polyacrylonitrile (PAN) based carbon fiber. Low-cost carbon fibers derived from lignin are currently being investigated at the University of Tennessee, because using lignin as a precursor could significantly reduce production costs. Lignins obtained from the pulp and paper and the emerging biofuel industries have the potential to be used for carbon fiber production, however, they are typically unsuitable because of the high levels …

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 …