Life Sciences Commons^™

Heirloom Seeds Of Tennessee: Seeds And Their Stories, Fiona Evelyn Mcanally

Masters Theses

Heirloom seeds continue to be grown in home gardens of Tennessee, an area of high agrobiodiversity, but are rapidly declining in local communities. Individual seed savers in communities have been replaced by formal networks that include seed swaps and national and regional seed saving organizations. Seed saving organizations grew out of an increased interest in heirloom vegetable production over the last forty years as a result of the expanding local food movement and concerns of loss of biodiversity. This study uses a multidisciplinary approach in plant and social sciences to document seed saving, the motivation of seed savers, and the …

Identification And Characterization Of Peak Activity, Environmental Variables, And Bacterial Pathogens In A. Americanum L. At Ames Plantation, West Tennessee, Brian Hendricks

Masters Theses

The status of tick-borne diseases (TBD) in the southeastern United States is uncertain due to a number of factors including, but not limited to emerging pathogens, misdiagnoses, and modifications to landscapes. Ehrlichiosis and rickettiosis are two of the most common TBDs; these are caused by Ehrlichia and Rickettsia bacteria that can be transmitted by a number of different tick species. The objectives of this study were to identify Amblyomma americanum (the Lone Star tick) peak activity and habitat preferences and characterize the potential role of A. americanum in tick-borne disease cycles in southwestern Tennessee. Using vegetation drags and CO_{2 …}

Single-Nucleotide Polymorphisms Associated With Performance Traits In Beef Cattle Grazing Endophyte-Infected Tall Fescue, Bryan Christopher Bastin

Masters Theses

Tall fescue (Lolium arundinaceum Schreb.) is the most prevalent forage in the Midsouth United States due in part to the presence of the endophytic fungus Neotyphodium coenophialum. The fungus, while conferring hardiness to tall fescue, contributes to decreased production efficiency in cow-calf operations. A previous genome-wide association study was performed using the Illumina 50k bovine SNP chip. Twenty-four SNP were found to be associated (P < 0.05) with adjusted birth weight and adjusted 205-day weights of calves from 48 beef cows at Ames Plantation. The first objective was to validate each SNP by testing associations with several additional phenotypes. Custom Taqman genotyping assays (Applied Biosystems, Foster City, CA) were subsequently designed to genotype each SNP in beef cattle located at Tennessee Tech University (n = 654), to validate associations in a large, independent herd. The results yielded 15 associations that were significant (P < 0.05) with 6 phenotypes linked to those affected by fescue toxicosis. The second objective investigated the link between fescue toxicosis and the XK, Kell blood group complex subunit-related, member 4 …

Molecular Systematics Of The Subfamily Phasiinae (Diptera: Tachinidae), Jeremy Daniel Blaschke

Masters Theses

The subfamily Phasiinae (Diptera: Tachinidae) is composed of obligate endoparasitoid flies that attack heteropteran insects, many of which are important agricultural pests. To lay a foundation for future studies in phasiine life history and their potential for use as biological control agents, the phylogenetic relationships within Phasiinae were explored using nucleotide sequences of two genes, CAD and LGL. A total of 63 taxa for CAD and 73 taxa for LGL were included in the analyses, representing 58 genera. Maximum likelihood inference methods were employed to reconstruct phylogenetic relationships in separate analyses of each gene and in a combined dataset. Phylogenetic …

Interactions In A Warmer World: The Relative Effects Of Experimental Warming, Intraspecific Density, And Insect Herbivory On Seedling Dynamics, Melissa Ann Burt

Masters Theses

Many effects of a changing climate for organisms, communities, and ecosystems are already apparent. Less studied are the effects of increases in temperature on species interactions. While warming may potentially disrupt interactions among species, species interactions may also mediate individual species responses to ongoing climatic change. In this experiment we manipulated temperature in field-based, open-top chambers for three years to examine the relationship between biotic interactions and climatic warming on the population dynamics of seedlings of Quercus alba. We investigated the effect of warming on rates of insect herbivory on Q. alba seedlings. Additionally, we assessed the relative effects …

Regulation Of Apolipoprotein C-Iii Gene Expression By Nuclear Receptors Hepatocyte Nuclear Factor 4 Alpha And Chicken Ovalbumin Upstream Promoter Transcription Factor Ii, But Not Retinoids In Hepatic Cells, Meredith Lee Howell

Masters Theses

Retinoic acid (RA) treatment induces hyperlipidemia in humans and animals. RA regulates the expression levels of various genes through the induction, repression, or coactivation of nuclear receptors, mediating its effects. RA-induced hyperlipidemia has been attributed to the induction of apolipoprotein CIII (gene, Apoc3), which inhibits lipoprotein lipase activity (LPL). We have shown that vitamin A (VA) status and retinoid treatment regulates hepatic lipogenic gene expression, suggesting that the induction of lipogenic genes may also contribute to hyperlipidemia. To test the hypothesis that retinoids may not affect Apoc3 expression, we analyzed the expression levels of Apoc3 mRNA in response to …

Monitoring Grassland Bird Populations On Fort Campbell Military Reservation, Kentucky-Tennessee, With A Special Emphasis On Bachman’S Sparrow (Peucaea Aestivalis), Emily Vera Hockman

Masters Theses

Grassland birds have declined more in the past four decades than any other group, primarily because of the suppression of ecological disturbance. Fort Campbell Military Reservation (FCMR) has maintained large amounts of grasslands and oak (Quercus spp.) savannas because of military training and prescribed fires, and supports many grassland bird populations. I established a survey route to investigate vegetation influencing occupancy of grassland birds with an emphasis on Bachman’s Sparrows (Peucaea aestivalis), and additionally described habitat selection of Bachman’s Sparrows on FCMR. Bachman’s Sparrow, Eastern Meadowlark (Sturnella magna), Henslow’s Sparrow (Ammodramus henslowii), and Orchard Oriole (Icterus spurius) occupancy were positively …

Structural Characterization Of The Redox-Dependent Differences In The Cytochrome P450cam-Putidaredoxin Complex Using Solution Nmr Spectroscopy, Nicholas John Lopes

Masters Theses

Complexation between proteins as part of biological electron transfer reactions is driven by precise interactions that are often characterized by short lifetimes, weak affinities and high turnover rates. These complex interactions are difficult to study structurally in physiologically relevant oxidation states due to their transient nature and/or large molecular sizes. One such protein complex in the cytochrome P450 family of enzymes that is of great interest to researchers due to its prototypical nature is the Putidaredoxin (Pdx)- cytochrome P450cam (CYP101) electron transfer complex that is involved in hydroxylation of D-camphor in the bacterium Pseudomonas putida. While the individual protein structures …

Studies On Solo Working Mechanism In The Meiosis Of Drosophila Melanogaster, Qian Ma

Masters Theses

In eukaryotes, sister chromatids are closely aligned due to cohesion, a process essential for chromosome pairing and segregation during both mitosis and meiosis. A conserved cohesin complex in a ring structure is composed of four subunits, including each of these four members or their homologs, SMC1, SMC3, SCC1/RAD21/REC8, and SCC3/SA. Up to now, no REC8 homolog has been identified in the meiosis of Drosophila. SOLO is a meiotic protein required for accurate chromosome segregation, centromere cohesion, and cohesin complex localization in Drosophila meiosis. In addition, SOLO is required for synapsis and recombination in Drosophila female meiosis.

In this study, …

Prevalence And Transmission Potential Of Borrelia Burgdorferi In Three Species Of Wildcaught Plestiodon Spp. Skinks Of The Southeastern United States, Teresa Dianne Moody

Masters Theses

In the southeastern United States, blue-tailed skinks (Plestiodon spp.) are important hosts for Ixodes scapularis ticks, the principal vector of Lyme disease (LD) in this region. Skinks and other southeastern lizards are not thought to be reservoir competent for Borrelia burgdorferi sensu stricto (Bbss), the etiological agent of LD in the United States. . Lizard-feeding by southeastern I. scapularis may tend to suppress sylvatic cycles of B. burgdorferi, and thus may be an important reason why LD case rates in the Southeast are much lower than in the Northeast and upper Midwest. Nevertheless, some skinks …

Content Analysis: Media Representation Of Infant-Feeding Practices Of Adolescent Mothers, Mary Elizabeth Pate-Bennett

Masters Theses

Background: The American Academy of Pediatrics considers breastfeeding to be the optimal form of infant nutrition ^1,2 and Healthy People 2020 objectives target increasing breastfeeding rates ³. Though national rates have improved, those among several subgroups have not. Adolescent mothers initiate breastfeeding only 58% of the time, which is lower than the national objective of 81.9%³. Research focusing on other health behaviors indicates that media may play an important role in developing these behaviors in adolescents. However, knowledge of media-influences on infant-feeding decisions and attitudes among adolescents is insufficient.

Objective: The objective of this study was to …

Preservation Of Nutrients In Cool- And Warm-Season Forages At Different Stages Of Maturity And Management, Jason Allen Shultz

Masters Theses

The overall goals of the studies described in this thesis were to investigate management practices of tall fescue and native warm-season grasses (NWSG) and find the best time to harvest and method to preserve forage quality. Study one investigated the effects of maturity on tall fescue and switchgrass and the effects of preservation method on forage quality. This study confirmed that maturity reduced forage quality in both tall fescue and switchgrass. Both tall fescue and switchgrass were successfully preserved as haylage or hay and did not differ in forage quality. Forages harvested before mid-May met the TDN and CP requirements …

Effect Of Choline Or Betaine Supplementation On Broilers Exposed To Different Temperature Treatments, Joseph D. Summers

Masters Theses

In this study, we looked at the effects of supplemental choline or betaine on broiler performance under different temperature conditions. In total there were eighty pens containing ten birds each for a total of 800 Cobb MX™ X Cobb 500™ (Cobb-Vantress, Incorporated, Siloam Springs, AR, USA). Each pen was randomly assigned to one of five dietary treatments in this study: Treatment 1, basal diet, Treatment 2, basal diet plus 500 methyl equivalents added choline, Treatment 3, basal diet plus 1000 methyl equivalents added choline, Treatment 4, basal diet plus 500 methyl equivalents added betaine, and Treatment 5 basal diet plus …

Activation Of Nucleotide Binding Oligomerization Domain Containing Protein 1 In 3t3-L1 Adipocytes: Effects On Adipocyte Differentiation And Lipolysis, Jaanki Shamb Purohit

Masters Theses

Obesity, defined as having excess adipose tissue, is associated with chronic inflammation. Adipose tissue is made up of many cell types, including preadipocytes and adipocytes. Both preadipocytes and adipocytes express pattern recognition receptors that play important roles in innate immunity. Two families of pattern recognition receptors that have been studied in adipose tissue are Toll-like receptors (TLRs) and NOD-like receptors (NLRs). Activation of TLR2 and TLR4 has been shown to lead to proinflammatory response in adipocytes, which is shown to suppress adipocyte differentiation and stimulate lipolysis, one of the major physiological functions of adipocytes. However, the effects of NOD activation …

Long Term Impacts Of A Genetically Engineered Microorganism (Gem) And Polycyclic Aromatic Hydrocarbons (Pahs) On Soil Bacterial Communities, Xiaoci Ji

Masters Theses

Microbes capable of polyaromatic hydrocarbon (PAH) biodegradation can be used to remediate soils contaminated with these persistent pollutants. To monitor in situ PAH-biodegradation, the bioluminescent bio-reporter Pseudomonas fluorescens HK44, containing a lux luminescent gene cassette inserted into its naphthalene degradation operon, was released into PAH-contaminated soil in lysimeters in 1996. Three treatments were imposed: strain HK44 mixed with PAH-contaminated soil (PAH+, HK44+; n=3); strain HK44 mixed with uncontaminated soil (PAH–, HK44+; n=2) and PAH-contaminated soil alone (PAH+, HK44–; n=1). The objective of this study was to assess the long term impacts of these treatments on the indigenous soil bacterial community …

Rutting Behavior And Factors Influencing Vehicle Collisions Of White-Tailed Deer In Middle Tennessee, Peyton Seth Basinger

Masters Theses

White-tailed deer (Odocoileus virginianus; deer) and human populations have expanded, and as a result, deer-vehicle collisions (DVCs) have become a primary concern. In particular, Arnold Air Force Base (AAFB) in Tullahoma, Tennessee, USA has had extensive problems with DVCs and has struggled to incorporate effective mitigation strategies. To address this issue, I initiated a study on AAFB to investigate deer behavior and factors increasing the likelihood of DVCs.

DVCs typically increase with peaks in deer activity during the breeding season (rut). I deployed GPS-ARGOS satellite collars on 10 adult males and 10 females during the summer of 2010. …

Alternative Poa Species As Permanent And Temporary Turfgrasses In The Transition Zone, Samuel Lucas Freshour

Masters Theses

As restrictions on water, fertilizer, and pesticide use increase, along with public pressure, turfgrass practitioners will need ways to meet the challenges of reduced inputs while still maintaining acceptable turf quality. Proper selection of turfgrass species and cultivars that are adapted to the climate, intended use, and level of expectation is the best and first line of defense for reduced input situations. The objective of this study was to evaluate alternative species from the bluegrass (Poa) genus for their performance as both permanent and temporary winter turfgrass species. In 2010 and 2011, 45 different treatments consisting of 37 different bluegrasses …

Ncaa Division Iii Coaches’ Attitudes And Receptivity Toward Sport Psychology Consulting Services, Page Grace Allen

Masters Theses

In this study NCAA Division III (D-III) head coaches (n = 731) completed an online survey assessing their attitudes (i.e., stigma tolerance, confidence in sport psychology consulting, personal openness, and cultural preferences) and receptivity toward sport psychology consultant (SPC) services, previous experiences with and access to SPC services, willingness to encourage and seek SPC services, support for possible SPC roles at NCAA D-III institutions, and if their attitudes predicted their willingness to use SPC services. Results indicated that coaches who had previous experiences with SPC services and perceived them to be effective were more willing to seek SPC services …

Seasonal Changes In White Adipose Tissue In American Black Bears (Ursus Americanus), Elizabeth Marie Hill

Masters Theses

American black bears have an intricate seasonal physiology, eating an entire year’s worth of food in 7-9 months, and then losing that weight during hibernation with almost no activity. The black bear thus represents a novel model in which to study seasonal regulation of food intake and metabolism. What controls the seasonal changes in fat deposition and metabolism in bears is unknown. Adipokines, such as leptin, regulate food intake and metabolism, and we hypothesized that these adipokines vary seasonally in bear adipose tissue, in a manner that correlates with fat storage. The study population consisted of wild bears from the …

Microarray Analysis Of Mrna Translation State In Arabidopsis Thaliana, Bayu Sisay Tiruneh

Masters Theses

The synthesis of proteins – translation – is one of the cellular processes that consume a great deal of energy. Genome-wide assays performed in Arabidopsis and other organisms have revealed that the translation status of mRNAs responds dramatically to different stresses and environmental and growth signals. Similar assays have revealed how translation of specific mRNAs is perturbed by genetic mutations in eukaryotic translation initiation factors (eIFs). I performed genome-wide analyses of translation state in A. thaliana seedlings with mutant genotypes for a specific eIF (subunit h of eIF3) and the large ribosomal protein, L24 (RPL24B). Using data from prior microarray …

Vegetation Response To Oak Savanna And Woodland Restoration In The Mid-South Usa, Andrew Lee Vander Yacht

Masters Theses

The decline and degradation of oak savanna and woodland communities throughout the Mid-South underscores the need to develop management techniques capable of their efficient and successful restoration. Therefore, my objectives for this work were to document plant community response to variations in canopy disturbance level, fire seasonality, and herbicide control of hardwood midstories. In Chapter One, I provide a thorough review of the current body of knowledge concerning open-oak communities and their restoration, with specific focus on herbaceous and woody plant response to canopy disturbance, fire, and herbicide midstory management. Chapter Two details the response of herbaceous and woody vegetation …

Revealing The Ecological Role Of Gemmatimonadetes Through Cultivation And Molecular Analysis Of Agricultural Soils, Mariam Naomi Fawaz

Masters Theses

Bacteria belonging to phylum Gemmatimonadetes are frequently detected in a variety of environments using culture-independent methods. Despite their ubiquity and prevalence, almost nothing is known about their physiology or ecology because so few strains have been isolated. The first objective of this study was to determine the distribution of Gemmatimonadetes within soil aggregates and the response of the relative abundance of Gemmatimonadetes to dry/wet cycling and soil management. The second objective was to analyze the effects of soil management, aggregate size, and atmospheric conditions on cultivability of Gemmatimonadetes. Universal and Gemmatimonadetes-specific 16S rRNA gene primers were used to …

Chemical Disinfectants For Inactivation Of Human Norovirus Surrogates, Cong Cao

Masters Theses

Human noroviruses (HNoVs) are considered the leading cause of acute non-bacterial gastroenteritis worldwide. Effective chemical disinfectants to inactivate HNoVs are needed. Since HNoVs cannot be cultivated in the lab, cultivable surrogates, feline calicivirus (FCV-F9) and murine norovirus (MNV-1), are used to determine inactivation using infectivity plaque assays. This study aimed to: 1) determine the ability of benzalkonium chloride (BAC) and potassium peroxymonosulfate (KPMS) to inactivate FCV-F9 and MNV-1 in vitro using suspension and carrier tests under clean and simulated dirty (5% fetal bovine serum) conditions over 1 h at room temperature; 2) determine inactivation of FCV-F9 and MNV-1 in suspension …

Comparison Of Roundup Ready And Conventional Soybean (Glycine Max L.) Weed Control Systems For Optimizing Yield And Economic Profitability, Brittany Lee Gaban

Masters Theses

Research was conducted in 2010, 2011 and 2012 at the East Tennessee Research and Education Center in Knoxville, TN, in order to compare differences in soybean yield among differing levels of weed control within Roundup Ready® [Glyphosate-resistant] (RR)and conventional soybean cultivars to gain a better understanding of the impact different intensities of weed control have on RR and conventional cropping systems. Results determined that after applying the weed control regimens, there was no significant difference (p

Glyphosate resistant weeds introduce new challenges and create a more costly weed control regimen, especially when using a RR based soybean cultivation operation. Therefore, …

Intensity Of Adoption Of Direct Marketing Strategies Among Fruit And Vegetable Farmers In Tennessee, Carey Ann Wolanin

Masters Theses

Consumer interest in fresher foods has increased over the past few years and has stimulated the growth of direct-to-consumer outlets. Tennessee currently hosts many types of direct food outlets, including farmer markets, CSAs, roadside stands, and pick-your-own operations. Using data from a 2011 survey of Tennessee fruit and vegetable producers, factors associated with the percentage of sales fruit and vegetable producers make through direct-to-consumer outlets or intensity of adoption of direct-to-consumer marketing strategies are evaluated using fractional logit and logit regressions. Findings suggest that the percentage of sales a producer makes through direct-to-consumer outlets is associated with farmer age, the …

Genetic Variation And Dispersal In Penstemon Hirsutus And P. Tenuiflorus, Anna Katherine Becker

Masters Theses

Studying plant-pollinator relationships essential for understanding angiosperm evolution. In the large endemic genus Penstemon (Plantaginaceae), shifts in pollination syndrome are proposed to be important for explaining taxonomic and morphological diversity (Wilson et al., 2004; Wolfe et al., 2006). However, little work has been done to determine the relationship between morphological and genetic divergence within pollination syndromes. This study utilized genetic data to explore whether divergence in corolla morphology among nine closely related, bee pollinated Penstemon species was consistent with pollinator-driven selection.

Bee pollinated species in Penstemon subsection Penstemon are often divided into two morphological groups based on inflation of the …

Soil Microbial Community Succession During Cadaver Decomposition, Kelly Lynn Cobaugh

Masters Theses

Microbes play critical roles in nutrient cycling in terrestrial ecosystems. In particular, microbial decomposition of organic matter is a key step in carbon and nutrient cycling, linking above-ground and below-ground pools. It is well known that the microbial community changes in structure and function following the introduction of organic matter into a terrestrial system. The decomposition of plant litter has been extensively investigated but the decomposition of animal-derived organic matter has often been overlooked. The unique characteristics of animal input are hypothesized to dictate a distinct decomposition process. This study examined the microbial community responsible for decomposition of animal-derived organic …

The Effect Of Photocatalytic Titanium Dioxide And Ultraviolet B Radiation On Sclerotinia Homoeocarpa Growth And Pathogenicity, Chun Hu

Masters Theses

Photocatalytic TiO₂ [titanium dioxide] generates strong oxidative effects when illuminated with ultraviolet (UV) light with wavelengths of less than 385 nm. UVB has wavelengths ranging from 280 to 315nm. Previous research indicates the oxidative species and UVB radiation can react and cause cellular damage to microorganisms, which may reduce Sclerotinia homoeocarpa growth and help to control dollar spot disease development. The objectives of this study were to investigate the interactions of TiO₂ and UVB radiation, both in vitro and in vivo, on the growth and development of dollar spot. Factorial treatments consisting of five rates of TiO₂ and three doses …

Impacts Of Preemergence Herbicides On Hybrid Bermudagrass Morphology, Patrick Alan Jones

Masters Theses

Preemergence (PRE) herbicides were evaluated in multiple experiments to determine their impacts on hybrid bermudagrass morphology [(C. dactolyn (L.) Pers. x C. transvaalensis (Burtt Davy)]. First, indaziflam and prodiamine were applied to hybrid bermudagrass rooted to various depths in either sand or silt loam mini-rhizotrons. Results indicated that prodiamine (a mitiotic inhibitor) and indaziflam (a cellulose biosynthesis inhibitor) both significantly reduced root length density compared to a non-treated control; however, indaziflam treated plants exhibited foliar injury (i.e., reddening, necrosis) while those treated with prodiamine did not.

The researchers surmised that reductions in root length density with indaziflam may compromise …

The Influence Of Organically Managed High Tunnel And Open Field Production Systems On Strawberry (Fragaria X Ananassa) Quality And Yield, Tomato (Solanum Lycopersicum) Yield, And Evaluation Of Plastic Mulch Alternatives, Jeffrey Thomas Martin

Masters Theses

High tunnels extend the production season, and increase fruit quality, yield and crop marketability of high-value crops, but have been underutilized in the Southeast. In this study, organically managed variety trials of two high-value crops, strawberry (Fragaria x ananassa) and tomato (Solanum lycopersicum), were conducted in high tunnel (HT) and open field (OF) production systems to compare yield and quality. Furthermore, specialty crops are commonly grown on black plastic mulch to increase earliness of harvest, fruit quality and yield. However, plastic disposal is time consuming and costly. Degradable mulches reduce removal costs, lessen environmental impacts, and …