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Full-Text Articles in Life Sciences

Identification Of Loci Influencing Teosinte Crossing Barrier 1 (Tcb1) Efficacy In Maize By Quantitative Trait Loci (Qtl) Mapping And Genome-Wide Association Study (Gwas), Namrata Maharjan Jan 2021

Identification Of Loci Influencing Teosinte Crossing Barrier 1 (Tcb1) Efficacy In Maize By Quantitative Trait Loci (Qtl) Mapping And Genome-Wide Association Study (Gwas), Namrata Maharjan

Electronic Theses and Dissertations

Pollen cross-contamination has been a major problem for maize breeders. Various mechanical methods applied to avoid the contaminations are ineffective. The genetic factors related to maize fertilization can be used to develop an effective method to prevent pollen contamination. Pollen rejection ability controlled by Teosinte crossing barrier 1 (Tcb1) is such a genetic system. Silks possessing dominant Tcb1-s reject pollen possessing the recessive allele (tcb1). Successful fertilization occurs when Tcb1-s pollen falls upon tcb1 silks. The efficacy of dominant Tcb1-s was, however, reduced when repeatedly backcross with maize inbred lines, which suggests that there are modifiers to Tcb1-s. To find …


The Effects Of Saline Soil On Microbiome And The Isolation Of Root-Associated Microbes To Relieve Salinity Stress, Duncan Jakubowski Jan 2021

The Effects Of Saline Soil On Microbiome And The Isolation Of Root-Associated Microbes To Relieve Salinity Stress, Duncan Jakubowski

Electronic Theses and Dissertations

Increasing levels of salinity in once-viable lands for crop production is a serious and growing problem in the Northern Great Plains. The objectives of this study were to determine the effects of saline soil on the microbial composition of plant roots and bulk soil, to measure metabolic changes in plant roots from saline soil, to determine the viability of root-associated microbes as inoculants to increase stress tolerance in plants, as well as determine the impact of saline soil on nitrogen cycling genes linked to greenhouse gas production. This study hypothesizes that high soil salinity levels have a significant impact on …


How Do Prey Capture And Simulated Fire Affect Growth And Nutrient Limitation In A Carnivorous Pitcher Plant, Sarracenia Alata?, Jalen Christopher Holloway Jan 2021

How Do Prey Capture And Simulated Fire Affect Growth And Nutrient Limitation In A Carnivorous Pitcher Plant, Sarracenia Alata?, Jalen Christopher Holloway

Electronic Theses and Dissertations

Carnivorous plants are defined as being able to benefit from the nutrients of prey in the environment, and have at least one trait that either retrieves, ingests, or lures a prey to its traps. The association of carnivorous plants with fire-prone habitats was initially described as a paradox, considering that carnivorous plants are often associated with nutrient-poor soils and fires can increase soil nutrient availability. This apparent paradox assumes, however, that the nutrients that increase in availability following fire are those also provided by prey, which might not be true. In habitats with nitrogen-poor soils, fire has been shown to …


Pollinator Ecology In Agroecosystems Of Eastern South Dakota, Isabela Beatriz Vilella-Arnizaut Jan 2021

Pollinator Ecology In Agroecosystems Of Eastern South Dakota, Isabela Beatriz Vilella-Arnizaut

Electronic Theses and Dissertations

Community structure contributes to ecosystem persistence and stability. To understand the mechanisms underlying pollination and community stability of natural areas in a human influenced landscape, a better understanding of the interaction patterns between plants and pollinators in disturbed landscapes is needed. Furthermore, understanding the potential conservation value in green spaces such as botanical gardens could assist in preserving and bolstering plant-pollinator interactions. Our study takes place in the Northern Great Plains which still retains extensive tracts of remnant temperate grassland habitat within a matrix of varying land-uses. First, we used a network-based approach to quantify how temperate grassland attributes and …


Creating A Georgia Southern Spider Collection: Can Dna Barcoding Help?, Guy B. Hobbs Jan 2021

Creating A Georgia Southern Spider Collection: Can Dna Barcoding Help?, Guy B. Hobbs

Electronic Theses and Dissertations

With over 280 spider (Araneae) species recorded within the State of Georgia, USA, the need for a well-documented natural history collection with a usable voucher system is critical to continually assess spider diversity and their future ecological impact in this region. Spider identification can be daunting for the inexperienced taxonomist; it is time consuming and sometimes requires destructive procedures. Previous works have successfully used an alternative method, DNA barcoding, to correctly identify spider species while preserving their morphology. This study set forth to create the core of a well-documented spider collection within Georgia Southern University’s Institute for Coastal Plain Science …


Assessing The Utility Of Environmental Dna Techniques To Monitor White Shrimp (Litopenaeus Setiferus) Abundance On The Georgia Coast, Raven Hurt Jan 2021

Assessing The Utility Of Environmental Dna Techniques To Monitor White Shrimp (Litopenaeus Setiferus) Abundance On The Georgia Coast, Raven Hurt

Electronic Theses and Dissertations

Environmental DNA (eDNA) surveys have developed over the last decade from once being a novel tool to now acting as an effective technology often used in complement to traditional capture surveys for assessing the distribution of organisms in freshwater and marine environments. However, many uncertainties on how to properly develop, operate, and analyze eDNA based techniques still hinder this technology effectiveness in the field. The white shrimp, Litopenaeus setiferus, is a common, commercially and recreationally important species in the United States, with landings exceeding $254 million in 2020. L. setiferus is also used as a key indicator species to changes …


Predation Threat In A Variable Landscape: Connecting Predation Risk To Nesting Success For The Seaside Sparrow (Ammospiza Maritima Macgilivraii), Corina D. Newsome Jan 2021

Predation Threat In A Variable Landscape: Connecting Predation Risk To Nesting Success For The Seaside Sparrow (Ammospiza Maritima Macgilivraii), Corina D. Newsome

Electronic Theses and Dissertations

Predation, the leading cause of nest-failure in birds, not only exists as a direct threat to nesting success, but may exacerbate other sources of nest mortality. Birds inhabiting Atlantic coastal marshes, such as Seaside Sparrows (Ammospiza maritima; hereafter SESP), are experiencing significant and rapid changes to their habitat, particularly sea level rise (SLR) and encroaching urbanization, that may affect the relative influence of nest predation on overall productivity. For SESPs, SLR presents an inherent threat to nest success in its potential to increase the frequency of nest flooding. In addition to this direct threat, the ability of SESPs …


Free-Roaming Cat Abundance Across A Habitat Gradient, Rachel E. Bird Jan 2021

Free-Roaming Cat Abundance Across A Habitat Gradient, Rachel E. Bird

Electronic Theses and Dissertations

There are an estimated 172 million owned and feral cats in the United States, and wildlife enthusiasts and cat owners are often at odds over how best to manage free-roaming cats. Management is needed because of the documented impacts of free-ranging cats on wildlife. Targeting these management efforts, however, is hampered by an imperfect understanding of cat distribution in the landscape. My study used game cameras and capture-recapture sampling to estimate abundance of free-roaming cats across a habitat gradient in Bulloch County, Georgia, USA. In all, I detected cats at 51% (25/49) sites with a mean of 2.1 cats per …


Novel Quantification And Localization Of Water And Solute Transporters In The Tissues Of The Spiney Dogfish (Squalus Acanthias), Tolulope B. Ojo Jan 2021

Novel Quantification And Localization Of Water And Solute Transporters In The Tissues Of The Spiney Dogfish (Squalus Acanthias), Tolulope B. Ojo

Electronic Theses and Dissertations

The dogfish, Squalus acanthias is a marine cartilaginous elasmobranch found in the North Atlantic and Pacific oceans. Dogfish synthesize and excrete urea as a product of nitrogen metabolism. They also convert ammonia into urea and retain this urea, such that their plasma is isosmotic or slightly hyperosmotic to the surrounding seawater. To facilitate the regulation of body fluid and to maintain ionic concentrations and osmotic pressure, Dogfish use ion and solute transporters (e.g., NCC, UT-1) and aquaporin water channel proteins. Studies have identified some of the aquaporin genes in the elasmobranch genome, but their functions are mostly uncharacterized. Recent transcriptomic …


Assessing Short-Term Microalgal Community Responses Over Altering Hydrological Conditions In Experimental Wetlands Of Costal Georgia, Maggie M. Kuhn Jan 2021

Assessing Short-Term Microalgal Community Responses Over Altering Hydrological Conditions In Experimental Wetlands Of Costal Georgia, Maggie M. Kuhn

Electronic Theses and Dissertations

Wetlands provide valuable ecosystem services such as nutrient cycling and carbon storage. Microalgae (i.e., diatoms) provide the foundation of primary production and determine rates of energy transfer throughout the system. Climate change models predict an increase in frequency of intense storms and severe drought conditions that pose a threat to known hydrological regimes and wetland ecosystem stability. The purpose of my study was to assess the effects of water permanence (i.e., duration of flooding) on diatom community structure in experimental wetlands. I predicted that wetlands with prolonged periods of flooding (i.e., permanent) would harbor a consistent diatom community throughout flooding …