Plant Breeding and Genetics Commons^™

Novel Tools And Datamining Techniques To Visualize And Interpret Historical Sugarcane Datasets, Zachary A. Taylor

LSU Master's Theses

Heritable genetic variation is an essential raw ingredient of variety development programs. This variation is acted upon via selection by identifying elite progeny that can be utilized agronomically or exploited as parents. Sugarcane breeders are tasked with creating optimal genetic variation through crossing. Prior knowledge of pedigree and parental performance allows breeders to discern which crosses to prioritize, since the time to make crossing decisions and the space to evaluate tens and thousands of progenies are both limited resources in sugarcane variety development programs. In this project, we have updated and validated the U.S. sugarcane pedigree …

Use Of High-Throughput Phenomics With And Without Fungicide As A Wheat Breeding Tool, Gerardo Ivan Rivera Collazo

Dissertations and Doctoral Documents, University of Nebraska-Lincoln, 2023–

Wheat (Triticum aestivum) is an important food staple for many countries around the world and current consumption and production data demonstrate a production deficit. Breeders are challenged to help close this gap in production by selecting better cultivars with improved yields. Several methods aim to accelerate the breeding process to reduce the time required for releasing an elite variety. One of the main breeding bottlenecks is the lack of fast and reliable phenotypic data acquisition that could dissect physiological and morphological plant data. High-throughput remote sensing could have the potential to reduce this bottleneck by streamlining data acquisition, …

Yield And Pungency Of Eight Onion Varieties And Their Response To Sulfur Fertilizer On Fine-Textured Soil, Charlie Rohwer, Jesen Hosch, Brianna Hayward, Cindy Tong

Midwest Vegetable Trial Reports

Onions are notable for their pungency, caused by sulfur-containing compounds. Fine-textured soils high in organic matter, or soils fertilized with organic amendments, are unlikely to require additional sulfur for maximum onion yield. We were interested in the impacts of additional sulfur (in such a situation, unlikely to be sulfur-limited) on pungency, soluble solids, and yield in eight onion varieties. We carried out a study in 2024 in southern Minnesota, designed as a split-plot (onion variety as the whole-plot) with four replicates. Heavy rainfall caused substantial unmarketability in our trial, with ‘Ringmaster’ suffering the most loss (11% of planted ‘Ringmaster’ were …

Integrating High Throughput Phenotyping Approaches To Characterize Plant Traits And Support Nutrient Management Research, Katie J. Bathke

Department of Agricultural and Biological Systems Engineering: Dissertations, Theses, and Student Research

Over the past decade, considerable research has addressed the social, economic, and agronomic challenges posed by imbalanced nutrient applications, particularly nitrogen and, more recently, sulfur. In response, high throughput plant phenotyping, as one of the latest approaches, has contributed to the development of innovative techniques for assessing key plant phenotypes under stress over time in both field and greenhouse environments. However, there is a limited number of studies applying these techniques for nutrient management, particularly in scenarios where two abiotic stressors coexist, such as the combination of water stress and nitrogen deficiency, or concurrent nitrogen and sulfur deficiencies.

In chapter …

Summaries Of Arkansas Cotton Research 2024, Fred M. Bourland

Arkansas Agricultural Experiment Station Research Series

Planted cotton acreage in Arkansas increased in 2024 to 670,000 planted acres, which was 160,000 acres more than in 2023 when Arkansas producers planted approximately 510,000 acres of cotton. A wet spring, and two hurricanes in three weeks in late summer/early fall led to a slight decrease in harvested acres that culminated in a final number of 640,000 (https://www.nass.usda.gov/Quick_Stats/Ag_Overview/stateOverview.php?state=ARKANSAS). Producers harvested 640,00 acres of cotton, which ranked third nationally, behind Texas and Georgia (https://downloads.usda.library.cornell.edu/usda-esmis/files/k3569432s/nk324887m/qn59s0097/cropan25.pdf). The total harvested acreage is the greatest amount since 680,000 acres in 2011. The average cotton yield in Arkansas in 2024 was …

Lethal And Sublethal Effects Of Cotton Expressing Single And Pyramided Proteins Of Bacillus Thuringiensis (Bt) On Helicoverpa Armigera (Lepidoptera: Noctuidae), Spodoptera Litura (Lepidoptera: Noctuidae), And Spodoptera Frugiperda (Lepidoptera: Noctuidae), Sharna Holman, Paul Grundy, Helen Spafford, Michael Furlong

Grain and Other Field Crops Research Articles

The susceptibility to proteins from Bacillus thuringiensis (Bt) can vary among lepidopteran pest species. While Bollgard 3 cotton (BG3) effectively controls the primary pest Helicoverpa armigera (Hübner) in Australia, its effectiveness against other pests, such as Spodoptera litura (Fabricius) and Spodoptera frugiperda (J. E. Smith), is unknown. This laboratory study assessed the survival and development of H. armigera, S. litura, and S. frugiperda larvae when fed foliage from a non-transgenic cotton variety (CC) and 3 transgenic cotton varieties: Bollgard (BG1) expressing Cry1Ac, Bollgard II (BG2) expressing Cry1Ac and Cry2Ab, and Bollgard 3 (BG3) expressing Cry1Ac, Cry2Ab, and Vip3A. Pyramided …

Integrating Genomic And Phenomic Breeding Tools For Wheat Stem Sawfly Resistance In Hard Winter Wheat, Sydney E. Graham

Dissertations and Doctoral Documents, University of Nebraska-Lincoln, 2023–

The wheat stem sawfly (WSS; Cephus cinctus) is an insect pest that affects wheat (Triticum aestivum) in the Northern Great Plains. This pest causes stem cutting that makes the plants susceptible to lodging and results in up to 30% yield loss. The primary management strategy for producers is utilizing host plant resistance, for which the main trait is stem solidness. This trait increases the pith thickness and provides resistance to the WSS by increasing larval mortality and reducing stem cutting. While stem solidness is largely controlled by a known major gene (SSt1), the phenotypic expression is also …

Leveraging Historical Data For Estimating Genetic Gain And Implementing Genomic Selection In A Student Led Barley Breeding Program, Sydney Graham

Department of Statistics: Dissertations, Theses, and Student Research

In Nebraska, winter feed barley presents an emerging market for producers and an opportunity to diversify cropping systems. The University of Nebraska Barley Breeding Program aims to develop high-yielding, winter-hardy varieties. A unique aspect of this program is that doctoral students serve as barley breeders and are responsible for crossing, data collection, and advancement decisions. While this provides hands-on experience for the students, the impact of student leadership has not been examined.

This study used a historical data set to evaluate the realized genetic gain of the breeding program, and as a training population for genomic selection. The dataset consisted …

Improved Management Strategies For Botrytis Fruit Rot, Macrophomina Root Rot, And Verticillium Wilt In California Strawberry Production, Joseph A. Ramirez

Master's Theses

Strawberry production in California is limited by plant diseases such as Macrophomina root rot (MRR) caused by Macrophomina phaseolina, Verticillium wilt (VW) caused by Verticillium dahliae, and Botrytis fruit rot (BFR) caused by Botrytis cinerea. Current disease management strategies are compromised due to fumigant regulations or ineffective disease management practices. This thesis investigated methods to potentially improve the management of these three diseases. Two host plant resistance evaluations for MRR and VW were conducted for the 2022-2023 and 2023-2024 growing seasons. Sixty-three strawberry genotypes were screened in both years. All plants were exposed to the pathogen via artificial …

Understanding The Impact Of Fall Armyworm (Spodoptera Frugiperda) Feeding, And Drought Stress On Drought-Tolerant And Drought-Resistant Soybean (Glycine Max)., Adriana G. Peissel

Crop, Soil and Environmental Sciences Undergraduate Honors Theses

Drought and insect herbivory are two major stressors on high-value crops like soybean (Glycine max). However, few studies have explored how these stressors interact, despite their presence in tandem under field conditions. We investigated how drought stress and fall armyworm (Spodoptera frugiperda) caterpillar herbivory impact Magellan (drought-tolerant) and Blackhawk (drought-susceptible) soybean cultivars. The soybean plants were subject to four treatment groups (1. Drought 2. Herbivory 3. Drought + Herbivory 4. Well-Watered) during a treatment period of 7 days in a greenhouse. We then measured plant height, physiological traits, trichome density, soil moisture, and larval mass gain. …

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

All Dissertations

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

All Dissertations

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 …

Investigating The Effects Of Gibberellin Treatments On Different Dwarf Millet Genotypes And Identifying The Mechanism Responsible For Genetic Dwarfism, Macie Mccarty, Audrie Miller, Quinn Calvert, Abi Waters, Dania Creary, Justin Coleman

2025 Student Academic Showcase

Gibberellins (GAs) are essential plant hormones involved in regulating growth and development, particularly in stem elongation, seed germination, and flowering. In cereal crops like millet, dwarf genotypes are of agricultural interest due to their potential for increased stability and yield efficiency. However, the genetic mechanisms underlying dwarfism in millet remain unclear. This study investigates the response of various dwarf millet genotypes to gibberellin treatments and seeks to determine the genetic basis of their dwarfism. We hypothesize that genotypes with gibberellin biosynthesis deficiencies will exhibit increased stem elongation when treated with gibberellin, while genotypes with signal transduction defects will show minimal …

The Effect Of Gibberellins On Dwarf Millet Growth, Rylee Deckard, Reed Morrison, Chase Christopher, Amy Brice, Sanduni Galbokka Hewa, Malina Roberson, Matthew Palmer

2025 Student Academic Showcase

Dwarf and semidwarf variants of agricultural plants are used to decrease lodging without decreasing crop yield. Some dwarf genotypes lack the ability to produce the growth hormone gibberellin, and others lack complete receptor pathways. Exogenous gibberellic acid (GA) was applied to four dwarf millet genotypes over the course of six weeks to determine what pathway for dwarfism each dwarf genotype was. Statistical analysis was done to analyze the relationship between GA applications and increased plant growth. It was found that all genotypes had some response to the treatment, though some were more extreme than others. Additionally, the treatment group had …

Agronomic Performance And Stability Of Padjadjaran Hybrid Maize In Different Agroecosystems, Farhan Fadhillah, Fiky Yulianto Wicaksono, Yuyun Yuwariah, Dedi Ruswandi

Jurnal Kultivasi

The development of high-yielding hybrid maize is a strategic step to address global food demand amidst climate change. This study evaluates the agronomic performance of 14 maize genotypes—10 newly developed F1 hybrids and 4 commercial checks—under two planting densities (95,000 and 55,000 plants/ha) across three agroecosystems (lowland, midland, and highland). The objectives were to identify superior and adaptive genotypes and analyze genotype × environment interactions using AMMI and GGE biplot methods. Genotype G12 exhibited the highest yield (338.4 g/plant) at high density, especially in the highland, but showed poor stability. In contrast, G5 demonstrated consistent performance and stability across environments. …

Arkansas Cotton Variety Tests 2024, F. Bourland, J. Gann, B. Lovelady, B. Guest Jr., J. Mcalee, L. Martin, Z. Treadway, C. Henderson

Arkansas Agricultural Experiment Station Research Series

The primary goal of the Arkansas Cotton Variety Tests is to provide unbiased data regarding the agronomic performance of cotton varieties and advanced breeding lines in the major cotton-growing areas of Arkansas. This information helps seed companies establish marketing strategies and assists producers in choosing varieties to plant. These annual evaluations will then facilitate the inclusion of new, improved genetic material in Arkansas cotton production. Adaptation of varieties is determined by evaluating the lines at five University of Arkansas System Division of Agriculture research sites (Manila, Keiser, Judd Hill, Marianna, and Rohwer). The 2024 tests at Keiser were adversely affected …

Crispr-Induced Mutagenesis Of Arabidopsis Thaliana Gene Apetala3, Hazel Frans, Tara Phelps-Durr

SACAD: Scholarly Activities

This project aims to create CRISPR-CAS9 mutations in the APETELA3 (AP3) gene of the model plant Arabidopsis thaliana. AP3 is a class B gene critical to the petal and stamen development of Arabidopsis flowers. AP3 is defined in a MADS domain, which binds directly to DNA and may be responsible for the expression of the CaRG-box genes. AP3 works in conjunction with PISTILLATA (PI), AGAMOUS (AG), APETALA1 (AP1), and SEPALLATA (SEP) genes to specify the development in the second and third whorls of the flower. While several alleles of AP3 already exist, these alleles are strong alleles that knockout gene …

Hordeum I Genome Unlocks Adaptive Evolution And Genetic Potential For Crop Improvement, Hao Feng, Qingwei Du, Ying Jiang, Yong Jia, Tianhua He, Yibin Wang, Brett Chapman, Jiaxin Yu, Hiawen Zhang, Mengxue Gu, Mengwei Jiang, Shanshan Gao, Xinjie Zhang, Yameng Song, Vanika Garg, Rajeev K. Varshney, Jianhua Wei, Chengdao Li, Xingtan Zhang, Ruifen Li

Grain and Other Field Crops Research Articles

Crop wild relatives (CWRs) are invaluable for crop improvement. Among these, Hordeum I-genome species exhibit exceptional tolerance to alkali and salt stresses. Here we present a chromosome-scale genome assembly of Hordeum brevisubulatum (II, 2n = 2x =14) and genome resequencing of 38 diploid germplasms spanning 7 I-genome species. We reveal that the adaptive evolution of the H. brevisubulatum genome is shaped by structural variations, some of which may contribute to its adaptation to high alkali and salt environments. Evolutionary duplication of the stress sensor-responder module CaBP-NRT2 and the horizontally transferred fungal gene Fhb7 were identified as novel alkaline–saline …

Inter-Simple Sequence Repeats Application On The Identification Of Genetic Variation Of A New Indonesian Melon Cultivar “Melona”, Tantri Ajeng Salma Salsabila, Adib Fakhruddin Yusuf, Wiko Arif Wibowo, Prima Sekti Kusnanda, Budi Setiadi Daryono

Makara Journal of Science

The field of identification of molecular markers has seen significant advancements, with the Inter-Simple Sequence Repeat (ISSR) emerging as a prominent tool for characterizing genetic variation within species. This study focuses on the new Indonesian melon cultivar “Melona,” developed through selective breeding of commercial melons. This study aimed to assess the utility of ISSR markers in evaluating the genetic variation and stability of the “Melona” cultivar. Comparisons were made with established cultivars—‘Inthanon,” “Rich Sweetness,” “Chamoe,” and “Hikapel”—using five ISSR primers: UBC 807, UBC 808, UBC 810, UBC 812, and UBC 826. A total of 70 DNA fragments with a high …

Morphological Characterization, Pollen Viability, And Germinability Evaluation Of Two Plumeria Species In The University Of The Philippines Los Baños, Darel Kenth S. Antesco, Maria Charito E. Balladares, Alangelico O. San Pascual, Pablito M. Magdalita, Fernando C. Sanchez Jr

The Philippine Agricultural Scientist

The genus Plumeria, locally known as kalachuci, is a popular ornamental tree belonging to the Apocynaceae family. The University of the Philippines Los Baños (UPLB) maintains a collection of Plumeria trees scattered across its campus; however, the origin of these trees remains unclear due to a lack of proper documentation. This study conducted morphological characterization and pollen analysis to provide information for further research. Results revealed the presence of 2 Plumeria species in the campus. P. obtusa has a linear leaf shape with acute tips and revolute margins while P. rubra has a lanceolate leaf shape. Additionally, P. …