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Item Genetics and Quantitative Trait Loci Mapping of Septoria Tritici Blotch Resistance, Agronomic, and Quality Traits in Wheat(North Dakota State University, 2013) Harilal, Vibin EranezhathMost breeding programs aim at developing superior germplasm and better cultivars that combine high yield, disease and pest resistance, and end-use quality to satisfy the requirements of the growers as well as industry. A population, consisting of 138 F2-8 recombinant inbred lines (RILs) derived from a cross between ‘Steele-ND’ and ND 735, was evaluated to study the inheritance pattern of the septoria tritici blotch (STB)-resistant genes, agronomic and quality traits. The framework map made of 392 markers, including 28 simple sequence repeat (SSR) markers and 364 DArT markers, spanned a total distance of 1789.3 cM and consisted of 17 linkage groups. The map position of quantitative trait loci (QTL) found in this study coincided with the map position of durable STB resistance genes, Stb1. Thirteen QTL were detected for agronomic and quality traits. More saturation of the current map is needed to explore more QTL for this population.Item Factors Affecting Grapevine Establishment in Northern Production Regions(North Dakota State University, 2011) Stenger, John EdwardTwo experiments were conducted to detect differences in growth and cold hardiness during establishment of northern grown wine grapevines. One experiment tested the use of four grow tube treatments and two pruning levels on vine establishment in the upper Midwest. The variables included leaf area, stem height, root growth, phenology, and hardiness. Overall, few significant differences occurred among treatments where grow tubes were utilized. In the second season, vines without grow tubes had superior measurements in nearly all leaf area categories. For this reason, it is recommended that growers refrain from grow tube use during establishment in northern growing regions. Vines pruned to three buds after transplanting varied little from those without pruning. For this reason, it is recommended that growers utilize the most efficient early pruning strategy for their particular situation. Another experiment was conducted to determine the effectiveness of different weed control measures. This experiment compared three kinds of mulches and an herbicide treatment on the growth and establishment of four wine grape varieties. Annual weed control, plant growth, phenology, soil water content and temperature, and vine hardiness were measured. Overall, vines receiving mulch had more consistent annual weed control and reduced early season growth when compared to chemically treated vines. For this reason, mulch is recommended in the vineyard for annual weed control during establishment in situations where vigor is not unacceptably low.Item Identification and mapping of QTL associated with crown rust resistance in recombinant inbred lines of oat (Avena sativa L.)(North Dakota State University, 2024) Yeruva, Cerly RiniCrown rust caused by Puccinia coronata f.sp. avenae is the most destructive fungal disease threatening oat production worldwide. Therefore, a search for novel sources of genetic resistance is considered essential to combat the evolving races of pathogen. The objectives of this study were to develop two recombinant inbred line mapping populations carrying novel sources of crown rust resistance and identify the genomic regions associated with crown rust resistance. 108 and 112 F5:6 RILs developed from each of the bi-parental crosses were evaluated for disease incidence in field and greenhouse under randomized complete block experimental designs with two replications. Genotyping and linkage analysis of markers associated with RILs revealed a major QTL underlying disease resistance in each population respectively. The two QTL identified in this study showed consistency across all the tested locations and the markers associated with the QTL appear to be useful for marker-assisted selection in oat breeding programs.Item Optimizing Winter Camelina Production as a Cover Crop In North Dakota(North Dakota State University, 2020) Wittenberg, Alex Shawn RobertWinter camelina [Camelina sativa (L.) Crantz] has gained particular interested from producers and researchers in the northern Great Plains and local production information is critical. Without a correct sowing date plant stand establishment can be challenging. Morphological differences between winter- and summer-biotypes of camelina can allow producers and researchers to distinguish the two biotypes. Visible and non-visible seed differences can offer effective means to distinguish the two biotypes. Seed quality of camelina is crucial. Sowing in September until the first week of October had similar seed yield. Morphological differences in the upper most developed leaves of camelina seedling can be used to distinguish the two biotypes. Field grown samples of camelina can be analyzed to determine if the seed is winter or summer biotype or a mix of both and we developed a near infrared spectroscopy protocol to determine seed composition of intact camelina seeds.Item Kentucky Bluegrass Establishment Under Saline, Waterlogging, and Saline-Waterlogging Conditions(North Dakota State University, 2022) Rue, KevinKentucky bluegrass (Poa pratensis L.) (KBG) is commonly used for golf fairways, however, it is sensitive to salinity and waterlogging. The objectives of this research were to determine (1) KBG growth response to saline, waterlogging, and saline-waterlogging conditions and (2) efficacy of seed priming in stress enhancement. Nine KBG cultivars were subjected to the aforementioned stresses at the seedling stage for four weeks. The combined saline-waterlogging caused more severe damage than individual stress. ‘Sudden Impact’, ‘Award’, ‘Limousine’, and ‘Kenblue’ were relatively tolerant to the stresses based on results from tissue biomass, root length, and specific root length stresses, while ‘Moonlight’ and ‘Blue Note’ were relatively sensitive. Seeds primed with abscisic acid, glycinebetaine, polyethylene glycol, and water performed better or similar to the non-primed grasses. Use of relatively tolerant cultivars, alone or in combination with priming, may be a better management practice when establishing a turfgrass stand under stress.Item Pre-Breeding to Improve Yield and Disease Resistance of Hard Red Winter Wheat(North Dakota State University, 2020) Barry, Dylan MitchellChallenges to growing winter wheat in North Dakota include winter temperature and disease pressure. Fusarium head blight (FHB) is a devastating disease that necessitates breeding for resistance. In the NDSU breeding program FHB resistance genes are often associated with a decrease in performance. This study used single seed descent to advance lines while maintaining a near random population. Early generation (F4) selection focused heavily on yield and the presence of FHB resistance quantitative trait loci to develop winter wheat lines with FHB resistance and high yield. Stripe rust is a fungal disease that is becoming increasingly problematic in North Dakota. To assess the available stripe rust resistance in the NDSU winter wheat germplasm, two sets of diverse breeding lines were used for stripe rust resistance phenotyping and genotyping by sequencing. The phenotype and genotype data were then used to locate resistance genes through genome wide association study.Item Wheat Traits Variations, Associations, and Potential Improvement from Crosses of Elite X Non-Adapted Germplasm(North Dakota State University, 2011) Mantovani, Eder EduardoWheat improvement most often has been accompanied by a narrowing germplasm base, as newer cultivars have been derived from intercrosses between elite germplasm. However, there is a concern that narrow germplasm may restrict breeding improvement for important traits such as resistances to new biotic and abiotic stresses. In addition to germplasm base, the wheat kernel is a major component of wheat grain yield and an important factor for milling characteristics. Focusing on wheat kernel characteristics might be a key element to improve wheat genotypes for agronomic and quality traits. With the intention to broaden the wheat germplasm, and to explore the associations between kernel traits and agronomic as well as quality traits, a two-year study was initiated in 2009 to examine the influence of the kernel traits on the agronomic and quality attributes of a 160 Recombinant Inbred Lines (RIL) population developed from an adapted (ND 705) and a non-adapted genotype (PI 414566). The experiment was conducted at Prosper and Carrington, North Dakota, during 2009 and 2010. The RIL population had a better performance at Carrington than Prosper due to favorable climatic conditions at this location, in 2009 and 2010. The results in this study showed that kernel traits had a high correlation among them and they exhibited continuous variations suggesting a polygenic inheritance. Grain yield, kernel volume weight (KVW), and flour extraction were highly correlated with kernel width, length/width ratio, weight, and area. Eight RIL yielded better than the adapted parent ND 705 and two of the RIL along with three checks were significantly superior for gram yield compared with the other genotypes across all environments. Although the non-adapted parent has a facultative grown habit, several RIL required fewer days to flower compared to the adapted parent. Two RIL had better flour extraction compared to the other genotypes included in this study. These results indicated that kernel traits can play a significant role in improving agronomic and quality traits. Higher values for grain yield, KVW, and flour extraction were significantly associated with spheroid or round shape (short and plump), large, and heavy kernels. The high agronomic and quality attributes showed by some RIL demonstrated that the use of a non-adapted parent can broaden the genetic variability while increasing the genetic gain for certain traits. Also, breeders should pay attention to kernel size and shape during the parental selection for the development of populations with improved agronomic and quality traits.Item Association Mapping to Identify Sclerotinia sclerotiorum Genomic Regions Affecting Aggressiveness of Lesion Formation on Sunflower Stems(North Dakota State University, 2019) Belay, Kassaye HussenSclerotinia sclerotiorum is one of the most destructive pathogens of sunflower in the United States and worldwide. Distinctive symptoms include mid-stalk rot, basal stalk rot and head rot from subsequent infection of the sunflower head. This fungal pathogen has a remarkably broad host range of over 400 dicot plants. However, little is currently known about the virulence strategies that allow S. sclerotiorum to successfully infect a wide range of plant hosts. The goal of our project was to identify S. sclerotiorum virulence determinants and effectors that contribute to disease development on sunflower. We evaluated a diverse collection of 232 S. sclerotiorum isolates for aggressiveness of mid-stalk lesion formation on two sunflower inbred lines. In addition, we performed genotyping-by-sequencing on 191 isolates to identify genetic markers for genome-wide association mapping to identify candidate genes associated with aggressiveness. A total of eight loci associated with variation in aggressiveness were identified.Item Gene Expression Associated with Wound and Native Periderm Maturation in Potato Tubers(North Dakota State University, 2011) Neubauer, Jonathan DavidPotato (Solanum tuberosum L.) is the world's fourth largest food crop and large financial losses are incurred each year from wound and bruise related injuries. However, little is known about the coordinate induction of genes that may be associated with, or mark major wound-healing and periderm maturation events. Also, one of the key defense mechanisms for potato tubers is the robust barrier provided by the phellem (skin) of the native periderm. Many biological processes are involved in the formation of this stout tissue. However, little is known about induction of genes that may be associated with this process. The objectives of this research were to molecularly assess the processes of wound periderm development and maturation, and native periderm maturation in potato tubers. In this study, these processes were determined in coordination with expression profiles of selected genes. The cell cycle, cell wall protein, and pectin methyl esterase genes were determined from two diverse potato genotypes and two harvests NDTX4271-5R (ND) and Russet Burbank (RB) tubers; 2008 and 2009 harvests. Cell cycle genes encoding epidermal growth factor binding protein (StEBP), cyclin-dependent kinase B (StCDKB), and cyclin-dependent kinase regulatory subunit (StCKS1At) expression profiles were coordinated with related phellogen formation and the induction and cessation of phellem cell formation. Genes encoding the structural cell wall proteins extensin (StExt1) and extensin-like (StExtlk) expression profiles suggested involvement with closing layer formation and subsequent phellem cell layer formations. The coordinate induction and expression profile of StTLRP, a gene encoding a cell wall strengthening "tyrosine- and lysine-rich protein," suggested a role in the formation of the closing layer followed by phellem cell generation and lastly cell wall thickening in nonmeristematic phellogen cells. StPME and StPrePME expression increased during periderm development, implicating involvement in modifications for closing layer and phellem cell formation. Collectively, these results indicate that the genes monitored were involved in and their expression profiles markedly coordinated with periderm formation and the on-set of periderm maturation; results were more influenced by harvest than genotype. Importantly, StTLRP was the only gene examined that may be involved in phellogen cell wall strengthening or thickening after cessation of cell division.Item Herbicide Screening in Industrial Hemp (Cannabis sativa L.) Production(North Dakota State University, 2021) Mettler, Joseph EricLack of labeled herbicides for industrial hemp (Cannabis sativa L.) production in the U.S. accentuates urgency to identify herbicides for weed control. Weed competition reduced seed yield by 25 to 32%. Pre- and post-emergence herbicide experiments were conducted to evaluate hemp tolerance to herbicides and support efforts for herbicide registrations. For post-emergence herbicides, hemp response to clopyralid (105 g ae ha-1) and bromoxynil (280 g ae ha-1) exhibited the lowest phytotoxicity, up to 38%, with no reduction of yield compared with the hand-weeded check. Pre-emergence herbicides were more viable options because pendimethalin (1120 g ai ha-1), trifluralin (840 g ai ha-1), saflufenacil (38 g ai ha-1), and pyroxasulfone (109 g ai ha-1) resulted in less than 17% visible hemp injury and increased seed yield by 18 to 33% compared with the non-treated, weedy check.