Digital Commons Network^™

Genetic And Mirna Transcriptomic Analysis Of Autoregulation Of Nodulation Signaling In Medicago Truncatula, Diptee Chauligain

All Dissertations

Legumes can source nitrogen from the air through biological nitrogen fixation inside root nodules formed in a symbiosis with rhizobia. A complex root-to-shoot-to-root signaling pathway called Autoregulation of Nodulation (AON) controls the number of nodules formed depending on the plant’s nitrogen requirements. In Medicago truncatula, the MtSUNN receptor complex in the shoot binds to the root-generated AON signals, peptides called MtCLEs, resulting in downregulation of miR2111 expression in the shoot, with the effect of decreased transport of miR2111 to the roots. Decreased miR2111 levels in the roots then cause an increase in transcript levels of the miR2111 targets MtTML1 …

Development And Evaluation Of An Automated Linear Move Fertigation System For Cotton Using Active Remote Sensing, Stewart Bell

All Theses

Optimum nitrogen (N) application is essential to the economic and environmental sustainability of cotton production. Variable-rate N fertigation could potentially help farmers optimize N applications, but current overhead irrigation systems normally lack automated site-specific variable-rate fertigation capabilities. The objective of this research was to develop and evaluate an automated variable-rate N fertigation system based on real-time Normalized Difference Vegetation Index (NDVI) measurements from crop sensors integrated with a lateral move irrigation system. For this purpose, NDVI crop sensors and a flow meter were integrated with Arduino microcontrollers and an automated fertigation system was constructed. A computer program was developed to …

Northern Giant Hornet (Vespa Mandarinia) And Yellow-Legged Hornet (Vespa Velutina), Potential Pests Of Honey Bees, Benjamin Andrew Powell

Agricultural Education

Exotic hornets present a significant threat to apiculture. Recent introductions of the yellow-legged hornet to Europe and the asian giant hornet to North America have made it critical that regulators, beekeepers and the general public be able to detect and identify these exotic hornets and to understand their biology to minimize the potential impacts to apiculture in South Carolina were they to be introduced.

Stem-Inhabiting Fungal Communities Differ Between Intact And Snapped Trees After Hurricane Maria In A Puerto Rican Tropical Dry Forest, François Maillard, Erin Andrews, Molly Moran, Peter G. Kennedy, Skip Van Bloem, Jonathan S. Schilling

Publications

Hurricanes impact forests by damaging trees and altering multiple ecosystem functions. As such, predicting which individuals are likely to be most affected has crucial economic importance as well as conservation value. Tree stem-inhabiting fungal communities, notably rot-causing agents, have been mentioned as a potential factor of tree predisposition to hurricane damage, but this assumption remains poorly explored. To examine this relationship, we sampled the stem wood of intact and damaged trees shortly after Hurricane Maria in a Puerto Rican dry tropical forest in 2017. We categorized samples depending on two types: trees with intact stems and trees in which stems …

Variable Fall Climate Conditions On Carbon Assimilation And Spring Phenology Of Young Peach Trees, Brian T. Lawrence, Juan Carlos Melgar

Publications

Variable fall temperature and moisture conditions may alter leaf senescence of deciduous fruit trees, influencing carbon assimilation before dormancy and phenology the following spring. This study explored gas exchange of young peach trees (Prunus persica (L.) Batsch) when senescence proceeded normally or was delayed during the fall under two soil moisture treatments: Well-irrigated trees or water deficit. Results showed leaf carbon assimilation was similar between the senescence treatments, but whole tree assimilation was estimated to be greater in delayed senescence trees compared to normal senescence trees based on timing of defoliation and total leaf area. The effect of soil moisture …

Uav-Assisted Water Quality Monitoring, Cengiz Koparan

All Dissertations

Water quality assessment for the management of water resources requires the collection of water samples for physical, chemical, and biological analysis. It is essential to reduce the cost of water quality monitoring by minimizing the number of grab samples and to reduce the sampling time by rapidly accessing the sampling points. Adaptive, remote, and smart water sampling systems can provide more effective water quality monitoring programs. An adaptive water sampling system with an unmanned aerial vehicle integrated with sensor nodes was developed and tested in this research. Individual phases of this research were; in-situ water quality measurements with a UAV-integrated …

Toxoplasma Gondii Requires Its Plant-Like Heme Biosynthesis Pathway For Infection, Amy Bergmann, Kathleen Floyd, Melanie Key, Carly Dameron, Kerrick C. Rees, L. Brock Thornton, Daniel C. Whitehead, Iqbal Hamza, Zhicheng Dou

Publications

Heme, an iron-containing organic ring, is essential for virtually all living organisms by serving as a prosthetic group in proteins that function in diverse cellular activities ranging from diatomic gas transport and sensing, to mitochondrial respiration, to detoxification. Cellular heme levels in microbial pathogens can be a composite of endogenous de novo synthesis or exogenous uptake of heme or heme synthesis intermediates. Intracellular pathogenic microbes switch routes for heme supply when heme availability fluctuates in their replicative environment throughout infection. Here, we show that Toxoplasma gondii, an obligate intracellular human pathogen, encodes a functional heme biosynthesis pathway. A chloroplast-derived …

Habitat Features And Behavioral Plasticity Promote Barred Owl Presence In Developed Landscapes, Marion Alice Clement

All Theses

Despite extensive accounts in the literature describing Barred Owls (Strix varia) as obligate forest-interior species that are sensitive to development, Barred Owls have increasingly been found in urbanized landscapes. Due to the limited number of studies on Barred Owls within the context of development, our understanding of the processes that facilitate Barred Owls within anthropogenic landscapes is limited. In the Piedmont region of the southeastern United States, South Carolina, the presence of Barred Owls in suburbs and small-town centers precipitated our research team to examine which habitat features facilitate their occurrence near development.

We conducted surveys using callbacks and autonomous …

Comparative Lipidomic Analysis Reveals Heat Stress Responses Of Two Soybean Genotypes Differing In Temperature Sensitivity, Sruthi Narayanan, Zolian S. Zoong Lwe, Nitant Gandhi, Ruth Welti, Benjamin Fallen, James R. Smith, Sachin Rustgi

Publications

Heat-induced changes in lipidome and their influence on stress adaptation are not well-defined in plants. We investigated if lipid metabolic changes contribute to differences in heat stress responses in a heat-tolerant soybean genotype DS25-1 and a heat-susceptible soybean genotype DT97-4290. Both genotypes were grown at optimal temperatures (OT; 30/20 °C) for 15 days. Subsequently, half of the plants were exposed to heat stress (38/28 °C) for 11 days, and the rest were kept at OT. Leaf samples were collected for lipid and RNA extractions on the 9^th and 11^th days of stress, respectively. We observed a decline in …

Gender Differences In Diet-Induced Steatotic Disease In Cyp2b-Null Mice, Melissa M. Heintz, Rebecca Mcree, Ramiya Kumar, William S. Baldwin

Publications

Nonalcoholic fatty liver disease (NAFLD) is the most common liver disease; however, progression to nonalcoholic steatohepatitis (NASH) is associated with most adverse outcomes. CYP2B metabolizes multiple xeno- and endobiotics, and male Cyp2b-null mice are diet-induced obese (DIO) with increased NAFLD. However, the DIO study was not performed long enough to assess progression to NASH. Therefore, to assess the role of Cyp2b in fatty liver disease progression from NAFLD to NASH, we treated wildtype (WT) and Cyp2b-null mice with a normal diet (ND) or choline-deficient, L-amino acid-defined high fat diet (CDAHFD) for 8 weeks and determined metabolic and molecular changes. CDAHFD-fed …

Comparative Transcriptome Profiling Provides Insights Into Plant Salt Tolerance In Seashore Paspalum (Paspalum Vaginatum), Peipei Wu, Steven Cogill, Yijian Qiu, Zhigang Li, Man Zhou, Qian Hu, Zhihui Chang, Hong Luo, Rooksana E. Noorai, Xiaoxia Xia, Christopher Saski, Paul Raymer

Publications

Background

Seashore paspalum (Paspalum vaginatum), a halophytic warm-seasoned perennial grass, is tolerant of many environmental stresses, especially salt stress. To investigate molecular mechanisms underlying salinity tolerance in seashore paspalum, physiological characteristics and global transcription profiles of highly (Supreme) and moderately (Parish) salinity-tolerant cultivars under normal and salt stressed conditions were analyzed.

Results

Physiological characterization comparing highly (Supreme) and moderately (Parish) salinity-tolerant cultivars revealed that Supreme’s higher salinity tolerance is associated with higher Na+ and Ca2+ accumulation under normal conditions and further increase of Na+ under salt-treated conditions (400 mM NaCl), possibly by vacuolar sequestration. Moreover, K+ retention under …

Lionfish (Pterois Volitans) As Biomonitoring Species For Oil Pollution Effects In Coral Reef Ecosystems, Peter Van Den Hurk, Ian Edhlund, Ryan David, Jacob J. Hahn, Michel J. Mccomb, Elizabeth L. Rogers, Emily Pisarski, Katy Chung, Marie Delorenzo

Publications

With oil spills, and other sources of aromatic hydrocarbons, being a continuous threat to coral reef systems, and most reef fish species being protected or difficult to collect, the use of the invasive lionfish (Pterois volitans) might be a good model species to monitor biomarkers in potentially exposed fish in the Caribbean and western Atlantic. The rapid expansion of lionfish in the Caribbean and western Atlantic, and the unregulated fishing for this species, would make the lionfish a suitable candidate as biomonitoring species for oil pollution effects. However, to date little has been published about the responses of …

Trait Differentiation And Modular Toxin Expression In Palm-Pitvipers, Andrew J. Mason, Mark J. Margres, Jason L. Strickland, Darin R. Rokyta, Mahmood Sasa, Christopher L. Parkinson

Publications

Background

Modularity is the tendency for systems to organize into semi-independent units and can be a key to the evolution and diversification of complex biological systems. Snake venoms are highly variable modular systems that exhibit extreme diversification even across very short time scales. One well-studied venom phenotype dichotomy is a trade-off between neurotoxicity versus hemotoxicity that occurs through the high expression of a heterodimeric neurotoxic phospholipase A2 (PLA2) or snake venom metalloproteinases (SVMPs). We tested whether the variation in these venom phenotypes could occur via variation in regulatory sub-modules through comparative venom gland transcriptomics of representative Black-Speckled Palm-Pitvipers (Bothriechis …