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Assessing Stress Tolerance Of Organelle Small Heat Shock Protein Mutants In Arabidopsis Thaliana, Parth Patel

Masters Theses

Molecular chaperones are proteins found in virtually every organism and are essential to cell survival. When plants are heat stressed, they upregulate and downregulate multiple genes, many of which are associated with the heat shock response. Small heat shock proteins (sHSPs) are one class of molecular chaperones that are upregulated during heat shock. They are proposed to act as the first line of defense by binding to heat sensitive proteins and preventing their irreversible aggregation. However, many details of sHSP function remain to be discovered and exactly what proteins they protect is unresolved. In addition to cytosolic sHSPs found in …

Does Invasion Science Encompass The Invaded Range? A Comparison Of The Geographies Of Invasion Science Versus Management In The U.S., Lara Munro

Masters Theses

Biases in invasion science lead to a taxonomic focus on plants, particularly a subset of well-studied plants, and a geographic focus on invasions in Europe and North America. Geographic biases could also cause some branches of invasion science to focus on a subset of environmental conditions in the invaded range, potentially leading to an incomplete understanding of the ecology and management of plant invasions. While broader, country-level geographic biases are well known, it is unclear whether these biases extend to a finer scale and thus affect research within the invaded range. This study assessed whether research sites for ten well-studied …

Improvements To Solanum Tuberosum Cv. ‘Desireé’ Cell Suspension Culture And Nicotiana Tabacum Cv. ‘Petit Havana’ Shoot Induction., Jessica Slade Layton

Masters Theses

Since the 1980s, progress in biotechnology has harnessed the incredible potential of plant biology. Plants have been engineered to be pest and herbicide resistant, enhance stress tolerance, and produce pharmaceutical proteins. Despite these feats of genetic engineering, plant tissue culture remains a limiting factor for future research. Unfortunately, the pressure to quickly innovate and produce novel products has pushed aside research to optimize tissue culture and exploring underlying molecular mechanisms for improved culture conditions. Efficient tissue culture methods are limited to a few plant taxa and are sometimes described in an oversimplified manner under the assumption they are facile to …

Phytophthora Capsici In Tennessee: Fungicide Resistance, Population Genetics And Cultural Control, Timothy Brent Siegenthaler

Masters Theses

Phytophthora capsici, a plant pathogenic oomycete, is the causal agent of the vegetable disease Phytophthora blight of pepper and cucurbits. Since the identification of P. capsici in 1922, a significant amount of research has been conducted to understand its biology and disease management. Despite this, little research had been conducted on this species in the state of Tennessee. Three studies were done from 2018 to 2020, focusing on fungicide resistance, population genetics, and testing management strategies in the field. In 2018 and 2019 a total of 248 isolate of P. capsici were collected from five counties in Tennessee. These isolates …

Forage Species Selection For Transitional Organic Production In The Southeastern United States, Jonathan Kubesch

Masters Theses

Despite the vast production markets for forage and organic products nationally, so far limited work has been done to develop organic forages specifically for Middle Tennessee or the mid-South in general. The present organic research field focuses on vegetable and grain production; however, forage production offers an easier transition for producers moving into certified organic agriculture. The present study seeks to evaluate several forage blends for optimizing forage production under low-input transitional organic conditions. Ideally a forage system could be tailored to the beef cattle operations of Middle Tennessee, the dominant forage consumption market in this region of the mid-South. …

Genome-Wide Associations Detect Allele Dose-Dependent Metabolism And Transport Genes As Basis For Variation In Sweetpotato Storage Root Culinary Profiles, Tara Elizabeth Rickman

Masters Theses

Previously considered a poor man’s crop, sweetpotato production is increasing globally due to its complex carbohydrates and other health benefits. Developing superior cultivars for various emerging market niches is imperative to sustaining and growing the production of sweetpotatoes. Culinary profiles such as sugar composition, organic acids and storage root color are vital for selecting sweetpotatoes targeted for various value-added products. To determine the genetic architecture and candidate genes underlying these culinary profiles, a genome wide association study on 23 traits was performed in over 700 sweetpotato accessions representing global genetic diversity. A new NGS-based quantitative reduced representation sequencing approach (omeSeq/qRRS), …

Effects Of Cooling And Postharvest Storage Methods On Broccoli Quality, Sarah Parker

Masters Theses

Broccoli (Brassica oleracea L. var. italica) is a cool-weather vegetable that is grown for its edible flowering heads and stalks. Broccoli inflorescences are immature plant organs with high respiration rates, resulting in a rapid loss of quality after harvest. The effects of cooling and storage methods on postharvest broccoli quality were evaluated based on metabolite contents of broccoli samples stored for 0, 7, 14, 21, 28, and 35 days. Sugar and organic acid contents were measured for broccoli harvested Fall 2018. Contents were compared for two cultivars (‘Diplomat’ and ‘Arcadia’) and two temperature treatments (not precooled and stored at 6 …

Influence Of Living Plant Roots And Mycorrhizal Hyphae On Soil Hydraulic Properties, Katelyn M. Marcacci

Masters Theses

The interrelationships between vegetation, soil, and water are fundamental in evaluating the projected impacts of global climate change. Many predictive models require soil hydraulic parameters as inputs. As most hydraulic parameter datasets are for repacked soil, the influence of vegetation on hydraulic parameters is not thoroughly understood. Living roots and mycorrhizal fungi cause physicochemical alterations in soils. Quantifying how vegetation influences soil hydraulic parameters is necessary to more accurately simulate soil water dynamics in climate models.

Laboratory experiments were conducted to test if the presence of roots and roots inoculated with mycorrhizal fungi have a significant effect on the saturated …

Processes, Patterns, And Predictions Of Soil Moisture Variation In Upland And Peatland Cranberry Farms In Massachusetts, Rebecca Brennan

Masters Theses

The American Cranberry (Vaccinium macrocarpon Ait.) represents a vital sector of the economy of southeastern Massachusetts. Due to the hydrogeological and edaphic characteristics of peatlands, variations in soil drainage and soil moisture represent major management challenges for growers in Massachusetts. An emerging trend of upland (mineral soil) cranberry farms planted with new hybrid cultivars has the potential to enhance the profitability and long-term viability of cranberry production in Massachusetts. However, sparse data exist on soil moisture characteristics of peatland and upland cranberry farms. The purpose of this research was to elucidate the differences in soil moisture between upland and …

Effects Of Chemical Variation On Competition And Insect Communities Across Solidago Altissima Genotypes, Bryan Scott Foster Ii

Masters Theses

Individuals within a plant species can differ greatly from one another, especially regarding the range of chemical compounds produced. However, the functions of many of these chemicals are unknown, but likely include defenses against herbivores, attractants for pollinators and seed dispersers, as well as mechanisms for resource competition. To assess the effects of foliar chemical composition on interspecific plant competition and insect communities, I conducted a common garden and greenhouse experiment using 24 genotypes of the allelopathic species Solidago altissima for which the foliar chemistry had been characterized. Using these data and chemical profiles of S. altissima, I linked …

Comparison Of The Effects Of Growing-Season Burns And Dormant-Season Burns On Vegetation Structure And Grassland Bird Diversity In East-Central Illinois Prairies, Joseph Lee Boise

Masters Theses

For managed grasslands, prescribed burns are a method to manage species composition by preventing crowding by bunch grasses and woody encroachment. While dormant-season (spring) burns are routinely performed, managers have recently introduced growing-season (late summer/fall) burns to prairies in east-central Illinois. The purpose of this study was to compare the effects of dormant-season and growingseason burns on vegetation structure and associated avian diversity. Specifically, objectives were to determine if: (1) Growing-season burns increase bird diversity or density of rare/declining species relative to dormant season burns; (2) Growing-season burns cause more bare ground to open and reduce litter and woody species …

Evaluation Of The Symbiotic Relation Between Endophyte And Poplar Trees Exposed To Landfill Leachate, Catalina Vega Hurtado

Masters Theses

“The contamination of soil and groundwater from leachate leakage from landfill has turned, nowadays, into a global public issue. One of the main concerns about this pollutant is the potential threat to human and ecosystem health. The current research studied endophyte bacteria in association with poplar trees (Populus sp.), as a method of bioremediation of landfill leachates. The objective of the project was to identify treatment strategies that may improve plant performance (survival rates, plant fitness, and degradation efficacy) with the purpose of being implemented in phytoremediation plots, aimed to intercept and treat landfill leachate, before the contamination of watershed. …