Digital Commons Network^™

Evaluation Of Novel Management Options For Bacterial Spot Of Peach, Daniela Moreno

All Theses

Xanthomonas arboricola pv. pruni (Xap) is an economically important pathogen causing bacterial spot of stone fruits worldwide. In the southeastern US management for this disease relies on copper and oxytetracycline (OTC) sprays, yet disease incidence remains high especially when the environmental conditions are conducive (warm and rainy). To further complicate disease management copper tolerant and OTC resistant (OTC^R) strains of Xap have been reported in the southeastern peach orchards. complicating disease management. Therefore, we aim to evaluate potential chemical and biological alternatives for disease management. The first objective was to evaluate a novel nano nanoformulation Bz (Zinc Borate) …

Understanding Movement, Habitat Use, And Habitat Selection By Largemouth Bass (Micropterus Nigricans X Salmoides) And Alabama Bass (Micropterus Henshalli) On Lake Hartwell, South Carolina, Deon Kerr

All Theses

Alabama Bass (Micropterus henshalli) were illegally introduced into the upper Savannah River Basin 15-20 years ago and have since become abundant as well as problematic ecologically. Acoustic telemetry was used to quantify diel movement, habitat use, and habitat selection of Alabama Bass and Largemouth Bass in Lake Hartwell, SC across seasons (June 2021-July 2022) with the goal of informing ongoing habitat enhancement efforts. Across all seasons, Alabama Bass conducted diel horizontal migrations from deeper offshore habitats during the day to nearshore, shallow habitats at night. Daytime Alabama Bass movement rates in offshore waters were higher than nighttime movement rates. Largemouth …

An Economic Impact And Investment Analysis Of Armillaria Root Rot In The United States Peach Industry, Gracie Herrin

All Theses

Peach production in the United States has decreased over the last decade due to increased disease prevalence. Armillaria root rot (ARR) is a lethal root fungus that affects many stone fruits, including peaches, often leading to rapid decline/death of trees and abandonment of orchards. This thesis is divided into four chapters which focus on answering four key questions that, to the best of my knowledge, have not been addressed in previous industry research.

The second chapter determines the magnitude of ARR disease prevalence in the United States and producers’ maximum willingness to pay (WTP) for a theoretical ARR-resistant rootstock. Results …

Characterization Of Colletotrichum Nymphaeae Isolates From Apple With Reduced Sensitivity To Fluazinam And Tebuconazole, Rulyu Meng

All Theses

Apple bitter rot is caused by Colletotrichum nymphaeae and other Colletotrichum species and management relies primarily on synthetic pesticides. Very few fungicides are effective against the disease and resistance has further limited their usefulness. A recent study indicated relatively low EC₅₀ values (the concentration required to inhibit 50% of mycelial growth in vitro) of C. nymphaeae isolates from Brazilian apples to fluazinam and tebuconazole, two fungicides that are not routinely used for bitter rot control. Isolates on opposite sides of the sensitivity range were designated either sensitive (lowest EC₅₀ values) and reduced-sensitive (highest EC₅₀ values). The objective …

Unmanned Ground Vehicle Proximal Sensing For Forage Biomass Production Estimations, Curtis Erwin

All Theses

A large increase in productivity could be realized by small increases in efficiency and utilization on grasslands due to their large area. Pre-harvest biomass estimations can help forage producers make better informed management decisions. Producers of dry hay and hay silage can better identify plant growth stages and the optimal time to harvest. Grazers can better determine the most efficient number of animals and stocking density. The goal of this study was to create a novel pre-harvest biomass estimation method utilizing compressed height combined with an unmanned ground vehicle (UGV). A compression plate named a “compression ski” was constructed and …

Impact Of Housing And Management On Production, Behavior, And Welfare Of Dairy Cows In Automatic Milking Systems, Lindsey Eve Davis

All Theses

The overall objective of this research was to determine the impact of Automatic Milking System (AMS) housing and management practices on cow production, behavior, and welfare of Holstein dairy cows. The first objective was to identify factors at the farm and cow level associated with lameness on AMS farms through decision tree analysis to allocate probabilities to each input. Results indicated this novel multifactorial approach of data analysis enabled us to highlight critical points that can be focused on to lessen cow-level complications or enhance farm-level housing and management practices to reduce the incidence and severity of lameness in AMS …

Venomic Characterization Of A Medically Relevant Rear-Fanged Snake, Conophis Lineatus (Dipsadidae: Xenodontinae), From Middle America, Tristan Schramer

All Theses

Most traditional research on snake venoms has focused on front-fanged snake families (Viperidae, Elapidae, and Atractaspididae). However, venom is now generally accepted as being a much more broadly possessed trait within snakes, including species traditionally considered harmless. Unfortunately, due to historical inertia and methodological challenges, the toxin repertoires of non-front-fanged snake families (e.g., Colubridae, Dipsadidae, and Natricidae) have been heavily neglected despite the knowledge of numerous species capable of inflicting medically relevant envenomations. Integrating proteomic data for validation, we perform a de novo assembly and analysis of the Duvernoy’s venom gland transcriptome of the Central American Road Guarder (Dipsadidae: Xenodontinae: …

In Vitro Rooting Techniques In Prunus Spp. For Propagation And Disease Screening For Armillaria Root Rot (Arr) Resistance, John Lawson

All Theses

Prunus is a genus widely cultivated to produce edible fruit including almond (P. amygdalus), peach (P. persica (L.) Batsch), cherries (P. avium and P. cerasus), among others. The cultivation of Prunus is economically important for several regions of the United States and relies on appropriate cultivars and rootstocks that are adapted to a growing region. Encroaching plant pathogens are forcing breeders to use sexually compatible germplasm from related species for introgression of novel alleles that confer tolerance or resistance. This is especially true in the rootstock breeding where interspecific hybridization is often used …

Addressing Meloidogyne Enterolobii Spread In The Sweetpotato Industry: Development Of A High Throughput Survey Detection Method For Root-Knot Nematodes And Quantification Of M. Enterolobii Damage On Storage Roots In Long-Term Assays, Julianna Culbreath

All Theses

Meloidogyne enterolobii is an aggressive root-knot nematode (RKN) species that has emerged as a significant pathogen of sweetpotato in the Southeastern US. Meloidogyne enterolobii is spread through the movement of infected ‘seed’ sweetpotatoes used for propagation, and the RKN resistance in commercial sweetpotato cultivars has proven ineffective against this nematode. This has prompted regulatory agencies to impose quarantines on regions infected with M. enterolobii. Sweetpotato storage roots can be rendered unmarketable due to M. enterolobii infection, resulting in potential overall yield loss. Visual detection of RKN in sweetpotato can be unreliable, and further distinguishing M. enterolobii from other RKN species …

Effect Of Metal Ions And Temperature On Stability Of Thiamine Determined By Hplc, Jhong Huei Huang

All Theses

Thiamine degradation occurs during storage and transportation for short and long periods due to the exposure to several factors, such as heat, oxidation-reduction reactions, and alkali. In this study, the effects of four metal ions (i.e., Cu⁺, Cu²⁺, Fe²⁺, and Fe³⁺) on thiamine stability in aqueous solutions at three temperatures (i.e., 25, 40, and 55°C) for the storage time of 7 days were discussed. Thiamine degradation was found to follow the first-order kinetic reaction, and the degradation rate could also be estimated. The factors in influencing thiamine stability included pH values, temperatures, …

If You Give A Beetle A Maple: Anoplophora Glabripennis Habitat Selection Patterns On An Island In South Carolina, Meredith Bean

All Theses

At the epicenter of the Asian longhorned beetle (Anoplophora glabripennis Motschulsky) quarantine zone in South Carolina, a small island containing an actively growing subpopulation of A. glabripennis had not completely killed its 37 host trees in 2020. Before these trees were removed and destroyed according to the USDA Eradication Program protocols, I performed an observational study to examine the microhabitat selection tendencies of the invasive A. glabripennis within this satellite infestation. After cataloging >14,000 oviposition sites and >1,600 exit holes created by A. glabripennis, I found dispersal trends according to a host’s stem status (single or multi-stemmed), vertical …

An Evaluation Of Bovine Reproductive Function From The Microrna Expression In The Female To Performance Testing In The Male, Erin Amiss

All Theses

Reproductive function is crucial to the success of a beef or dairy herd. Both the female and male play significant roles in the outcome of bovine reproduction. The bull contributes to reproductive success in many ways, such as genetics. The initial role that the bull has in reproductive success is fertilization, whether natural or by artificial insemination. One method of assessing bull performance are central bull test stations, which are traditionally administered by a university, extension center, or are privately owned. Central bull tests assess the performance of bulls from various management systems, breeds, and ages. Some measurements taken during …

The Effects Of Tubulin Post-Translational Modifications On The Flagellar Motility Of Trypanosoma Brucei, Katherine Wentworth

All Theses

Trypanosoma brucei is a parasitic kinetoplastid that causes African trypanosomiasis and is transmitted to a mammalian host by the tsetse fly (Glossina spp.). T. brucei relies on its flagellar motility to carry out its morphological changes from the procyclic form (predominant in the fly vector) to the bloodstream form (infectious form in mammals) and navigate the bloodstream of its host. The driving structure within the flagellum is the axoneme, which is composed of microtubules and dynein motor proteins. The tubulin code hypothesis suggests that cells regulate microtubule motor protein activity through post-translational modifications (PTMs) of alpha and beta …

Patterns Of Occurrence Of The Black Basses In The Upper Savannah River Tributaries Of Georgia And South Carolina With Emphasis On Bartram’S Bass Micropterus Sp. Cf. Coosae, Caroline Cox

All Theses

Aquatic ecosystems are among the most threatened in the world due to anthropogenic alterations to the natural landscape and native biotas. Identifying the local and landscape-level environmental factors that influence the occurrence of endemic species can help protect aquatic ecosystems by facilitating predictions of where hybridization or replacement with generalist species may occur across the landscape. The need for such predictions is pronounced for black bass species in the southeastern United States. Bartram’s Bass (Micropterus sp. cf. coosae) is a provisional species of conservation concern. Allelic frequencies of Bartram’s Bass in Savannah River reservoirs and tributaries have been …

Investigating The Biochemical Properties Of A Novel Mutation, A194v, In Human Rad51, Briana Vollbeer

All Theses

DNA double-strand breaks (DSB) are one of the most serious DNA lesions because improper repair of a DSB can lead to loss of heterozygosity, aneuploidy, and cancer. One of the primary pathways to repair DSBs is homologous recombination (HR). HR resects the DNA around the DSB and then uses homologous DNA as a template to restore the broken sequence. RAD51 has a vital function in this pathway by forming a nucleoprotein filament on a resected end of the DSB. The nucleoprotein filament searches for homology within the homologous DNA. Once homology is located, strand invasion followed by strand exchange occurs. …

Spring Gobbling Chronology And Turkey Habitat Use In Upstate South Carolina, Janelle Grehan

All Theses

Wild turkey (Meleagris gallopavo) is a highly popular game species harvested primarily during the reproductive season, which has driven substantial efforts to understand patterns of springtime habitat use and gobbling activity. Autonomous recording units (ARUs) have enabled researchers to collect unprecedented amounts of gobbling data, yet post hoc processing of audio data has been time-intensive due to false detection rates. Gobbling activity has been studied in the South Carolina Coastal Plain, but data for the Upstate are lacking. My objectives were to assess seasonal and weekly gobbling activity and turkey habitat use in Upstate South Carolina relative to …

Depot-Specific Patterns Of Mrna And Mirna Gene Expression In Adipose Tissue From Texel-Cross And Suffolk Lambs, Aliute-Nkoyo Udoka

All Theses

This work hypothesizes that miR-199a-3p influences SCD-1 expression and monounsaturated fat content of lamb fat depots. The objectives of this study were to: 1) measure miR-199a-3p, SCD1, and fatty acid composition in various tissues (longissimus muscle and liver) and fat depots (omental, mesenteric, subcutaneous, intermuscular, perirenal) in Suffolk and Texel-sired lambs, and 2) evaluate the role of miR-199a-3p in adipocyte hypertrophy in ovine stromal vascular (SV) cells in vitro. Suffolk lambs (n=4) and Texel-Suffolk cross lambs (n=5) were finished to day 203 of age. The liver, the longissimus muscle, kidney fat, mesenteric fat, omental fat, subcutaneous fat, and intermuscular fat …

Characterization Of Colletotrichum Nymphaeae Isolates, Causal Pathogen Of Apple Bitter Rot, With Reduced Sensitivity To Fluazinam And Tebuconazole, Rulyu Meng

All Theses

Apple bitter rot is caused by Colletotrichum nymphaeae and other Colletotrichum species and management relies primarily on synthetic pesticides. Very few fungicides are effective against the disease and resistance has further limited their usefulness. A recent study indicated a relatively low range of EC₅₀ values (the concentration required to inhibit 50% of mycelial growth in vitro) of C. nymphaeae isolates from Brazilian apples to fluazinam and tebuconazole, two fungicides that are not routinely used for bitter rot control. Isolates on opposite sides of the range were designated either sensitive (lowest EC₅₀ values) and reduced sensitive (highest EC_{50 …}

The Influence Of Water Stress And Rootstocks On Nutrient Uptake And Gas Exchange Of Young Peach Trees, Naif Alshammari

All Theses

Young peach trees are often rainfed in the southeastern U.S. and periods of dry weather can cause tree water deficit that can be detrimental to orchard productivity. There is a lack of understanding of the influence of water regimes and rootstocks on the nutritional status and gas exchange of the peach tree. Most peach growers in Southeastern United States do not irrigate their young peach trees because they do not produce fruit until the third leaf. In this region, peach growers use Guardian as a rootstock, although MP-29 is also interesting for growers with orchards that have Armillaria root rot …

Application Of A 14c-Assay To Assess Methanotrophic Biodegradation Of Tce In Low Ph Groundwater, Evan Groome

All Theses

Current biological strategies for remediating trichloroethylene (TCE) in low pH aquifers (i.e., pH14C-TCE assay was developed to determine pseudo first-order rate constants for the degradation of TCE in microcosms containing soil and groundwater from the Boeing Michigan Aeronautical Research Center (BOMARC) superfund site, where the pH ranges from 4.1 to 4.9. The ¹⁴C-TCE assay was also adapted to calculate soil-normalized rate constants for data from this site, as well as data that Szwast²¹ collected from the Beltsville Agricultural Research Center (BARC). In addition to natural attenuation, biostimulation through amendments of methane and nutrients were also assessed. This treatment …

The Effects Of Short Chain Fatty Acids On Clostridioides Difficile Growth, Sporulation, And Toxin Production, Michelle Baldassare

All Theses

Short chain fatty acids (SCFAs) are products of bacterial fermentation that help maintain important gut functions such as the intestinal barrier, signaling, and immune homeostasis. The main SCFAs acetate, propionate, and butyrate have demonstrated beneficial effects for the host, including importance in combatting infections caused by pathogens such as Clostridioides difficile. C. difficile infection (CDI) is a public health concern and causes 30,000 deaths each year mainly due to the overuse of antibiotics. Despite the potential role of SCFAs in mitigating C. difficile infection, their direct effect on C. difficile remains unclear. Through a set of in-vitro experiments, we …

The Presence And Distribution Of Crotoxin In The Rock Rattlesnake (Crotalus Lepidus), Jade Mellor

All Theses

Crotoxin and its homologs (hereafter all referred to as CTx) is a highly lethal heterodimeric beta-neurotoxin found in pitvipers (Crotalinae) and is the main driver of neurotoxic venom phenotypes (Type II). In contrast, hemorrhagic venom phenotypes (Type I) are characterized by high snake venom metalloproteinase expression and low toxicity. Although many rattlesnake species have been classified as either Type I or Type II, population level variation in venom phenotype has also been documented in several species. The presence or absence of CTx is the main component of this variation in venom phenotype and has been most widely studied in large-bodied …

Recruitment, Cost Indexes, And Management Of Box-Nesting Wood Ducks In South Carolina And North Carolina, Emily Miller

All Theses

The wood duck (Aix sponsa) has experienced one of the most significant declines and recoveries among species of North American waterfowl (Anatidae). With enactment of the Migratory Bird Treaty Act (1918) and installation of hundreds of thousands of artificial nest structures for this cavity-nesting species in North America, wood duck populations have recovered and remain a sustainable harvested resource. However, long-term research on box-nesting wood ducks conducted at the Savannah River Ecology Laboratory, Aiken, South Carolina, has revealed uncertainty as to whether recruitment rates of yearling females from natal box-nesting populations are self-sustaining without immigration of hens from …

Reproductive Ecology And Microbial Communities From Wood Duck Nest Boxes In Georgia And Florida, Jake Shurba

All Theses

Wood ducks (Aix sponsa) are an important game species throughout the Atlantic Flyway that was nearly extirpated by the early 20^th century due to overhunting and the loss of habitat. Wood ducks are secondary cavity-nesters that utilize artificial nest boxes and natural cavities. It is reported that the use of nest boxes is likely what led to re-establishment of the species in North America. Where boxes are numerous, overuse of boxes by multiple hens throughout a nesting season can occur and result in a buildup of bacteria, parasites and other potentially detrimental pathogens that can impact egg …

Identifying Temporal Sensitivity Of Poinsettia Flowering To High Temperatures, Paul Millar

All Theses

High temperatures can cause delayed flowering in poinsettia (Euphorbia pulcherrima Willd. ex Klotzsch), a phenomenon known in the industry as heat delay. The poinsettia wholesale market is concentrated to a relatively brief period from early-November through early-December putting growers at risk to heat delay. This problem is compounded by the unusual weather patterns created by climate change. The objective of this thesis was to identify periods in which poinsettia flowering is sensitive to high temperatures. First, the weeks within the growing season when the plants were sensitive to high temperatures were identified (Chpt. 2). Then within those sensitive weeks, …

Improved Molecular Detection Tools For The Invasive Crop Pest Helicoverpa Armigera (Hübner), Mitchell D. Rich

All Theses

Helicoverpa armigera is a major crop pest native to Europe, Asia, Australia, and Africa. H. armigera has recently invaded South America and has caused billions of dollars in agricultural losses. It is difficult to differentiate H. armigera from H. zea, a closely-related species native to North and South America. A few genetic tests have been previously developed to detect H. armigera DNA in pooled samples of moth legs. In this study, an improved qPCR melt curve assay with higher detection sensitivity and a field-based recombinase polymerase amplification (RPA) assay were developed for specific detection of H. armigera DNA …

Shelf Life Of Aquaponically-Grown Finstar Lettuce In Different Oxygen Transmission Rate Films, Katherine White

All Theses

The effects of oxygen transmission rate of packaging material on the shelf life of aquaponically-grown Finstar lettuce was studied. Parameters of packaging headspace gas composition (oxygen and carbon dioxide concentrations) and lettuce pH, percentage weight loss, total aerobic microorganisms, and color were analyzed every ten days for sixty days. Finstar lettuce was stored at 4^○C in four different types of packages (treatments), including a clamshell package and three film bags with oxygen transmission rates (OTR) of 3.0-6.0 cc/(m²/24 hr/1 atm), 80-90 cc/(m²/24 hr/1 atm), and >225 cc/(m²/24 hr/1 atm). Lettuce stored in …

Investigations Into Avian Skeletal Adaptations And Spine Fusion Events, Tori Huey

All Theses

Avian dinosaurs evolved skeletal adaptations resulting in numerous fused spinal structures, like the synsacrum, present in extant birds. The synsacrum is a highly fused region necessary for stiffening the spine, and it fuses the spine to the pelvic ilium. Conventional wisdom suggests that fusion occurred in ovo during embryonic development via the cartilage matrix that patterns the future vertebrae. We show that post hatch birds have intervertebral discs separating all vertebrae of the spine, leading us to re-examine this notion in chickens up to 10 weeks of age. Intervertebral discs undergo constant remodeling, then degenerate and undergo tissue clearance, followed …

Potassium Level Prediction Of Peach Tree Leaves Using A Hyperspectral Camera And Multivariate Analysis, Megan Io Ariadne Salimbangon Abenina

All Theses

The use of hyperspectral imaging is a valuable piece of technology used in precision agriculture. Hyperspectral imaging system could help farmers and researchers alike in analyzing tissue samples quicker compared to the current way of running a plant tissue analysis on the different nutrient levels that often takes time in generating results. The objective of this research was to measure the potassium level of peach trees using its leaves with a hyperspectral camera. The Senop HSC-2 was used to capture images of peach tree leaves during the fall of 2020 and 2021. The collected data were used to create a …

Evaluating The Impact Of Intersecting Research And Outreach Marine Science Programs On Elementary And Undergraduate Students, Randi J. Sims

All Theses

Climate change is one of the most destructive forces our ocean is currently experiencing. Despite this, many students are not taught the basics of climate change science and ocean literacy in public school systems. My work seeks to combat these deficits through educational experiences in marine science for undergraduate and local elementary students through three studies incorporating marine-science based research and outreach. (1) Through undergraduate marine science research and outreach, students enrolled for long durations or with positive mentorship increased their conceptual understanding of marine science concepts, altered their attitudes towards climate change and science, and were more likely to …