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Determining The Importance Of Propagule Pressure And Dispersal Mechanisms For The Establishment And Spread Of Crapemyrtle Bark Scale, Acanthococcus Lagerstroemiae Kuwana (Hemiptera: Eriococcidae), Erika Renee Wright May 2023

Determining The Importance Of Propagule Pressure And Dispersal Mechanisms For The Establishment And Spread Of Crapemyrtle Bark Scale, Acanthococcus Lagerstroemiae Kuwana (Hemiptera: Eriococcidae), Erika Renee Wright

Theses and Dissertations

Non-native scale insects can be economically and ecologically important pests of urban forests. Crapemyrtle bark scale (CMBS), Acanthococcus lagerstroemiae Kuwana (Hemiptera: Eriococcidae), is a scale that causes declines in plant vigor for a popular ornamental tree in the southeastern United States, crapemyrtle (Lagerstroemia spp.). CMBS has spread rapidly throughout the Southeast and, more recently, into the Middle Atlantic. Despite problems associated with CMBS, important aspects of its ecology, such as the role of propagule pressure in establishment and the relative importance of mechanisms for between-tree dispersal, are not well-understood. We used field and laboratory studies to investigate these aspects of …


Physiology Of Human-Equine Interaction During Substance Withdrawal, Molly Marie Friend May 2023

Physiology Of Human-Equine Interaction During Substance Withdrawal, Molly Marie Friend

Theses and Dissertations

Psychotherapy incorporating equine interaction (PIE) is emerging as an effective treatment for substance use disorder (SUD), but research is limited concerning physiological impacts during substance withdrawal. This study investigated impacts of PIE on salivary cortisol concentrations, heart rate, anxiety, and depression during SUD withdrawal. Heart rate and cortisol concentrations were measured in horses to determine potential human-horse coupling. Saliva samples and heart rates were collected pre and post PIE from residential SUD patients (n=18) and their therapy horses (n=4) during and following the withdrawal period. Participants (n=10) also completed a survey measuring anxiety and depression (P = 0.05). A …


Surface Modification Of Wood Using Nano-Sized Titania Particles Coated By Liquid-Precursor Flame Spray Pyrolysis, Ganesh Sedhain May 2023

Surface Modification Of Wood Using Nano-Sized Titania Particles Coated By Liquid-Precursor Flame Spray Pyrolysis, Ganesh Sedhain

Theses and Dissertations

Wood is a renewable resource and versatile material used in tasks ranging from tools and furniture to advanced engineering structures. Although wood is light, mechanically robust, environmentally friendly, and abundant, some inherent properties of wood, such as degradation due to moisture and UV radiation from sunlight, are less desirable for extended service life and dimensional stability. In this dissertation, a novel surface modification of wood is explored by depositing nano-sized titania particles on wood veneers and cross-laminated timber (CLT) blocks by liquid-precursor flame spray pyrolysis to confer reversible wettability switching and enhanced durability to UV irradiation. The reaction between a …


Evolution And Epidemiology Of Channel Catfish Virus (Ccv), Arun Venugopalan May 2023

Evolution And Epidemiology Of Channel Catfish Virus (Ccv), Arun Venugopalan

Theses and Dissertations

Channel catfish virus disease (CCVD) is the principal viral disease in the United States catfish industry. The CCVD is caused by channel catfish virus (CCV), with mortality reaching up to 100% in fingerlings. CCV is assigned taxonomically to the family Alloherpesviridae, genus Ictalurivirus, species Ictalurid herpesvirus 1 (IcHV-1). To date, virulence, immunogenicity, and genome plasticity of the CCV field isolates have not been investigated. Three genotypes of CCV (IcHV-1A, IcHV-1B, and BCAHV) were identified using restriction fragment length polymorphism (RFLP) analysis. Virulence assessment of three representative isolates of RFLP groups suggests that IcHV-1B (pooled survival [mean ± SE]: 58.3% ± …


Identification And Quantification Of Allelochemicals Associated With Weed Suppression In Sweetpotato, Varsha Varsha May 2023

Identification And Quantification Of Allelochemicals Associated With Weed Suppression In Sweetpotato, Varsha Varsha

Theses and Dissertations

Mississippi ranks among the leading states in sweetpotato production in the US. However, managing weeds in sweetpotato fields presents a significant challenge, and the limited availability of herbicides labeled for use in sweetpotato makes it even more challenging. The widespread and repeated use of herbicides has led to the development of weed resistance. In addition, herbicides are incompatible with the organic production system. Finding sustainable weed management strategies to provide weed control options for organic cultivation and detain the development of herbicide-resistant weeds under conventional crop production is imperative. The natural chemicals released by the plants, also called allelochemicals, can …


Interactive Effects Of Bark Beetles, Ophiostomatoid Fungi, And Subterranean Termites On Wood Decomposition And The Biogeochemical Cycling Of Pine Forests, Kimberlyn Pace May 2023

Interactive Effects Of Bark Beetles, Ophiostomatoid Fungi, And Subterranean Termites On Wood Decomposition And The Biogeochemical Cycling Of Pine Forests, Kimberlyn Pace

Theses and Dissertations

A frequent source of pine tree mortality in recent years can be attributed to pine bark beetles and their vectored Ophiostomatoid fungi, an organism that has been observed to attract subterranean termites that preferentially recruit to this downed woody debris. This interaction may significantly modify biogeochemical fluxes in bark beetle mass mortality events, but studies are often limited to singular regions or single pine-dominated ecosystems. Two studies were designed to test the interactive effects of these associations on terrestrial biogeochemical cycles and decomposition processes, the first using replicated field trials in Mississippi, Arizona, and Honduras across two years and the …


Physiological And Yield Responses Of Soybean Cultivars To Heat And Drought Stresses, Sadikshya Poudel May 2023

Physiological And Yield Responses Of Soybean Cultivars To Heat And Drought Stresses, Sadikshya Poudel

Theses and Dissertations

Soybean (Glycine max L.) is an important legume crop often exposed to heat and drought stresses during reproductive and early-seed setting stages, resulting in lower yields and seed quality. Ten soybean cultivars were phenotyped for individual (drought or heat) and combined stress tolerance. Under drought, reduced stomatal conductance and increased canopy temperature significantly reduced seed number (46%) and weight (35%). Heat stress alone reduced seed number (19%) and weight (23%) compared to control. Moreover, a degree increase in daytime temperature above 32 °C during the reproductive stage reduced seed weight by 4% and 7% under well-watered and drought conditions, respectively. …


Evaluation Of Nutrient Digestibility Of Weaned Calves From Early And Late Shedding Dams, Jennifer Keele May 2023

Evaluation Of Nutrient Digestibility Of Weaned Calves From Early And Late Shedding Dams, Jennifer Keele

Theses and Dissertations

Researchers have investigated several factors that could alter fetal growth, including nutrient restriction (Valiente et al., 2021), hair shedding (Gray et al., 2011), and extreme hot and cold temperatures (Davidson et al., 2022). Hot temperatures and increased humidity percentages in the southeast United States caused researchers to investigate the hair coats of Angus cattle in the commercial production setting. An improvement in fiber digestibility and calf birth and weaning weights has been observed in Angus dams that shed 50% of the winter hair coat by May (Gray et al., 2011; Burnett et al., 2021). Our objective of this experiment was …