Plant Breeding and Genetics Commons^™

Towards Improved Stress Resilience, Optimal Growth And Enhanced Biosafety In Transgenic Plants, Xiaotong Chen

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This dissertation investigates biotechnology strategies to improve plant stress resilience, growth, and biosafety in transgenic perennial grasses using creeping bentgrass as a model system. Functional analyses of non-coding RNAs such as miR164 and miR169 showed that regulatory non-coding RNAs influence plant architecture and abiotic stress responses through broad developmental and transcriptional networks, supporting them as valuable engineering targets for complex trait improvement. The dissertation also developed a dual recombinase platform for transgene containment and removal, linking trait engineering with biosafety control. Additionally, the recombinases themselves were examined for their potential impact on heterologous host and were found to reshape plant …

Sorghum Grain Secondary Metabolites And Underlying Genetics To Reduce Foodborne Pathogens In Poultry, Maria A. Conti

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The rise in antibiotic-resistant pathogens poses a threat to the poultry industry's ability to maintain animal health, prompting growing interest in alternatives to synthetic antibiotics. The use of non-tannin sorghum [Sorghum bicolor (L.) Moench] in poultry rations offers a valuable alternative, as this cereal grain has a high bioactive profile that can provide health benefits, including antimicrobial (AM) activity. The scope of this study was to examine the AM potential of non-tannin sorghum grain against Clostridium perfringens, a major foodborne pathogen that negatively impacts poultry health and production. To that end, the inhibitory effects of a non-tannin sorghum …

Breeding For Disease Resistance In Melon And Watermelon, Venkata Rao Ganaparthi

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Watermelon and cantaloupe are two widely consumed cucurbits, but their acreage in the United States reduced by nearly 50% in last two decades. Fusarium wilt caused by a soil borne pathogen Fusarium oxysporum f. sp. niveum(Fon) race 2 is a major limiting factor in watermelon production as it reduces yields by 80%. Grafting watermelon plants onto the root stock of wild, disease-resistant varieties like ‘Carolina Strongback’ is the best strategy to manage Fon race 2. Though effective, this approach increases production costs.

Part of this dissertation focused on finding more sustainable, cost-effective solutions to control Fusarium wilt …

Breeding Biofortified Protein Rich Organic Pulses For Better Human Health, Sonia Salaria

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Pulse crops are dry grains of legumes, the second most consumed plant crops in the world after cereals. These crops are one of the primary sources of plant-based protein and contain high concentrations of pre-biotic carbohydrates, minerals and vitamins. Recognizing the health benefits of pulses intake, their demands as sustainable food and changes in people’s diet preferences for plant-based protein have increased awareness for pulses consumption. With this scenario, improving the nutritional profile of pulse crops for rich nutrition has been an opportunity for breeders to explore and tailor the available germplasm to develop nutrient dense pulses. Furthermore, the genomic …

Identification And Characterization Of Intermediate Phenotypes To Decipher Genetic Architecture Of Stalk Lodging Resistance In Maize (Zea Mays L.), Bharath Kunduru

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Maize is a key contributor to global food security and incurs severe yield losses due to stalk lodging, the permanent displacement of plants from an upright growth habit due to mechanical damage to the stem (stalk). Stalk lodging resistance, an indicator of the stalk ability to resist lodging, is a complex trait and determined by several structural, geometric, and material properties of stalks, collectively referred to as intermediate phenotypes, whose identity and genetic framework are poorly understood. Therefore, progress in resolving the genetic architecture of stalk lodging resistance was impeded by a lack of standardized phenotyping methodologies and a poor …

Understanding The Genetic And Metabolic Underpinnings Of Complex Traits In C4 Grasses, Manwinder Singh Brar

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Maize (Zea mays L.) and sorghum (Sorghum bicolor (L.) Moench) are two important cereal crops cultivated worldwide for food, animal feed, and industrial products. Productivity of these crops is significantly impacted by various biotic and abiotic stresses, such as diseases, insect pests, drought, salinity, and heat. Among factors influencing crop performance under stress, the regulation of leaf longevity plays a critical role in determining yield. Leaf senescence is a highly regulated process essential for nutrient remobilization through the degradation of cellular components in aging leaves, but premature or accelerated senescence reduces photosynthetic efficiency and yield. Staygreen, a phenotype …

Investigate The Possibility Of Producing Healthier, Safer Peanuts Through Molecular Breeding And Novel Fungal Pathogen Management Strategies, Tariq Alam

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Peanut allergy, a critical health concern with high morbidity and mortality rates, is a leading cause of fatal anaphylactic reactions in the United States. Managing peanut allergy is challenging due to the prevalence of peanuts in processed foods and the risk of contamination. This dissertation evaluates the U.S. peanut mini-core collection for four major immunogenic proteins, Ara h1, Ara h2, Ara h3, and Ara h6, using gel electrophoresis, enzyme-linked immunosorbent assay, liquid chromatography, and mass spectrometry. The study identified 26 genotypes with reduced concentrations of allergenic proteins. Genome-wide association studies (GWAS) of protein traits revealed 10 significant SNPs and identified …

Enhancing Crop Resilience: Physiological And Omics Approaches For Drought And Heat Stress Tolerance In Soybean And Peanut, Jyoti Prasad Kakati

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Soybean and peanut are two major crops globally grown for oil and protein. Climate change-associated factors like drought and increased temperature (heat stress) challenge the global production of soybeans and peanuts. Though the United States is the second-largest producer of soybean and the fourth-largest producer of peanuts, it still faces production constraints associated with drought and heat stresses. In the present study, we have examined the responses of soybean and peanut plants to drought and heat stresses during germination and reproductive phases. We conducted field and controlled environmental studies to elucidate the impact of drought stress on germination and seedling …

Integrated Techniques To Identify And Characterize Resistance To Fusarium Wilt Caused By Fusarium Oxysporum, F. Sp. Vasinfectum Race 4 In Two Domesticated Gossypium Species, Stephen Parris

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Fusarium wilt of cotton (Gossypium hirsutum and G. barbadense), caused by Fusarium oxysporum f. sp. vasinfectum race 4 (FOV4), is the most threatening disease faced by today’s cotton breeders. During the past 20 years, over $7 million have been dedicated to efforts in breeding upland cotton for resistance to FOV4 while yielding little to no results. To counteract this, we conducted a study in Clint, TX, that utilized control plots and geostatistical methods to adjust phenotypic data for the heterogeneous distribution of FOV4 in the field, improving the accuracy of genetic resistance assessments. Concurrently, early-generation genetic mapping in …

Breeding Cotton For Determinate Growth Habit: Increasing Cotton Fiber Yield By Remobilization Of End-Of-Season Perennial Reserves, Salman Naveed

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Cotton (Gossypium spp.) is a major export commodity for the U.S. Despite advances in plant breeding and management practices, the cotton yield gains in the U.S. have stagnated. Therefore, to increase cotton fiber yield, we undertook a novel approach by altering the growth habit of cotton from perennial to annual. In this effort, eight genotypes showing strong expression alleles for five floral induction and meristem identity genes were selected from 44 Upland cotton mini-core collection genotypes and genetically crossed in various combinations to stack the strong expression alleles in a genotype. These efforts have allowed us to develop high-yielding, …

Lentil (Lens Culinaris Medik.) Prebiotic Carbohydrates And Protein Quality: Uncovering Genomic Associations And Developing Rapid Ftir Phenotyping Methods, Nathan Johnson

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Lentil (Lens culinaris Medik.) is a cool-season food legume cultivated around the globe. This pulse crop boasts a rich nutrient profile including high concentrations of prebiotic carbohydrates, protein, essential amino acids, and micronutrients, such as folate, iron, zinc, and selenium. Prebiotic carbohydrates promote a healthy gut microbiome, which, in turn, is associated with reduced risk of numerous pathologies including obesity/overweight, type II diabetes, irritable bowel disease, and colon cancer. Known as “poor man’s meat,” lentil also provides high quality plant-based protein at a low cost. As the world increasingly looks to crops to supplement and replace animal-based protein, lentil …

Crosscutting Understandings Of Fusarium Resistance In Sorghum And Wheat For Development Of Breeding Strategies And Novel Opportunities In Germplasm Improvement, Arlyn Ackerman

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Fusarium causes widespread disease in crops resulting in yield and quality loss across a range of host taxa that results in global incidence of carcinogenic mycotoxins contaminating the world’s food systems. This research sought to crosscut frameworks developed across the Fusarium host crop species of wheat (Triticum aesitivum) and sorghum (Sorghum bicolor [L] Moench) to further understand mycotoxin suppression and resistance. A deeper understanding of the biochemical resistances available in sorghum grain mold (SGM) was built by following research of wheat based upon deoxynivalenol resistance to Fusarium head blight (FHB). Through this research, phenotyping methods for Fusarium damaged kernels …