Theses and Dissertations at Montana State University (MSU)
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Item Impact of the D genome and quantitative trait loci on quantitative traits in a spring bread wheat by spring durum wheat cross(Montana State University - Bozeman, College of Agriculture, 2014) Kalous, Jay Robert; Chairperson, Graduate Committee: Luther E. TalbertDesirable agronomic traits are similar for common hexaploid (6X) bread wheat (Triticum aestivum, 2n = 6x = 42, genome, AABBDD) and tetraploid (4X) durum wheat (T. turgidum durum, 2n = 4x = 28, genome, AABB). However, bread and durum wheat are genetically isolated from each other due to an unequal number of genomes that cause sterility when crossed. Previous work allowed identification of a 6X and 4X parent that when crossed resulted in a large number of recombinant progeny at both ploidy levels. In this study, interspecific recombinant inbred line populations at both 4X and 6X ploidy with 88 and 117 individuals, respectively, were developed from a cross between Choteau spring wheat (6X) and Mountrail durum wheat (4X). Lines within each population contained a mixture of alleles from each parent for loci in the A and B genomes. The presence of the D genome in the 6X population resulted in increased yield, tiller number, and seed size. The D genome also resulted in a decrease in stem solidness, lower test weight and fewer seed per spike. Similar results were found with a second RIL population containing 152 lines from 18 additional 6X by 4X crosses. Several additional QTL for agronomic and quality traits were identified in both the 4X and 6X populations. Positive durum alleles increasing kernel weight in hexaploids, on chromosomes 3B and 7A may be useful for introgression by bread wheat breeders.Item Breeding for root lesion nematode resistance in Montana winter wheat(Montana State University - Bozeman, College of Agriculture, 2015) May, David Bruce, III; Chairperson, Graduate Committee: Philip L. BrucknerRoot lesion nematodes (RLN; Pratylenchus spp.) present a serious challenge to dryland wheat production worldwide. Development of resistant cultivars would provide great economic benefit to growers. From 2012-2013, a set of backcross lines (MT08185//MT08184/Persia 20) was screened twice for resistance to P. neglectus. Progeny and parent lines were grown in infested soil for 16 to 18 weeks. Nematodes were then extracted from roots of individual plants and counted to obtain per plant final populations. ANOVA results from the 2013 screen showed significant differences in mean P. neglectus populations among lines (p < 0.01). The median final population of susceptible parent MT08184 was an estimated 4.9 times greater than that of resistant parent Persia 20. A 2013 field trial in the absence of root lesion nematodes indicated reductions in grain yield, volume weight, and protein were not associated with resistance. Seven RLN-resistant lines were identified in field evaluations with agronomic phenotypes for yield, volume weight and protein comparable to those of five widely-grown checks. Identification of quantitative trait loci (QTL) for resistance to RLN will facilitate marker-assisted introgression of resistance genes in a backcross-breeding program. Single-marker analysis of 218 genome-wide single nucleotide polymorphism markers (SNPs) was performed to identify genomic regions associated with resistance to P. neglectus. The analysis identified putative marker-trait associations on chromosomes 1AL, 1DS, 2BL, 5BL, 5DL, 7AL and 7DL (all p < 0.05). Overall, phenotypic screens as applied were inadequate to consistently characterize wheat lines for RLN resistance. As such, RLN resistance phenotypes and putative QTL effects identified in the study must be verified in future experiments.Item A new virus-like disease of barley : its etiology, epidemiology, and the ultrastructure of associated virus-like particles(Montana State University - Bozeman, College of Agriculture, 1987) Robertson, Nancy LeeItem Conversion of AFLP markers to sequence-specific PCR markers in barley and wheat(Montana State University - Bozeman, College of Agriculture, 1999) Shan, XueyanItem Biosynthesis of bromegrass mosaic virus ribonucleic acid(Montana State University - Bozeman, College of Agriculture, 1967) Branson, Dean RussellItem Genetic routes to modulate rate of dry-matter disappearance of barley grain in the rumen of cattle(Montana State University - Bozeman, College of Agriculture, 2007) Jewell, Jeremy Burke; Chairperson, Graduate Committee: Tom Blake.Recent research has identified important characteristics of barley grain as feed for cattle. Of these, low ruminal dry-matter digestibility (DMD) is of particular importance as it is highly correlated with animal performance and with animal health. This research attempts to identify genetic loci that contribute to the ruminal DMD of barley grain. The utility of the barley ant18 mutation for decreasing ruminal DMD was investigated. The DMD of several barley cultivars and their ant18 mutations was investigated in a randomized complete block design in two environments. Genotype by environment interaction was present: in the greenhouse the DMD of ant18 mutants was less than that of the wildtype, and in a dryland field the reverse was true. Because of this interaction, ant18 is not likely to be a reliable method of modulating DMD. With the aim of identifying markers for marker-assisted selection (MAS), a 123-member inbred population was developed from a cross of Haxby and PI 28624. PI 28624 is a low DMD accession from the USDA barley collection.Item Functional analysis of Puroindoline genes in Wheat (Triticum aestivum)(Montana State University - Bozeman, College of Agriculture, 2008) Feiz, Leila; Chairperson, Graduate Committee: Michael J. Giroux.Grain hardness variation has large effects upon many different end-use properties of wheat (Triticum aestivum). The Hardness (Ha) locus consisting of the Puroindoline a and b genes (Pina and Pinb) controls the majority of grain hardness variation. Starch production is a growing end-use of wheat. The first objective of this study was to estimate the differences in starch yield due to natural and transgenically conditioned grain hardness differences. To accomplish this goal, a small scale wet milling protocol was used to characterize the wet milling properties of two independent groups of isogenic materials varying in grain hardness and in Pin expression level. The results of the first study demonstrate that the Ha locus and puroindoline expression are both linked to wet-milling starch yield and that selection for increased Ha function increases starch yield via enhanced separation of starch granules and the protein matrix during wet milling. The lack of Pin allelic diversity is a major factor limiting Ha functional analyses and wheat quality improvement. So the second objective of this study was to create new Ha alleles in the soft white spring cultivar Alpowa using ethylmethane sulfonate (EMS) mutagenesis. The M 2 population was screened to identify new alleles of Pina and Pinb. One hundred and forty eight new Pin alleles, including 68 missense alleles, were identified. F 2 populations for 49 of the new Pin alleles including 43 unique missense ones were developed after crossing each back to non-mutant Alpowa. Grain hardness was then measured on F 2:3 seeds and the impact of each allele on grain hardness was quantified. The tested mutations comprised a range of functionality from neutral to function abolishing mutations. Seed weight and vigor of all mutation lines was restored among all of the F 2 populations. The new alleles have the potential to improve end use properties of soft and hard wheats.Item Transformation of barley (Hordeum vulgare) using the wheat puroindoline gene(Montana State University - Bozeman, College of Agriculture, 2004) Odake, Yusuke; Chairperson, Graduate Committee: John E. Sherwood.Feed and malting barley are major crops in Montana. Harrington, a two-rowed spring malting barley variety, is the most cultivated variety in the state. Barley was the last of the world's major cereals for which transformation methods were developed because in vitro-cultured barley rapidly loses regeneration ability or gives rise to albino plants during selection for transformed tissue. Previous research used the variety Golden Promise because it regenerates well under research conditions, though it is not commercially used. Transformation could be an important method to improve varieties in North American barley cultivars. The puroindoline proteins (PINA and PINB) can be isolated from wheat endosperm and are basic cysteine and tryptophan-rich proteins that might play a role in defense against pathogens. The puroindolines show antifungal activity both in vitro and in vivo. Milk stage seeds were harvested to obtain embryos. Embryos were placed on induction media [2.5 mg/L 2,4-Dichlorophenoxyacetic acid (2,4-D) and 0.01 mg/L 6-benzylaminopurine (BAP)] for 12 to 51days until calli formed. The biolistic method was chosen for transmitting the gene of interest into the calli, using a Biolistic PDS-1000/He Particle Delivery System (BioRad, Hercules, CA) with 900 psi rupture disks. Approximately 4,500 calli were bombarded with two plasmids; pinA driven by the maize ubiquitin promoter (Ubi1) which is expressed constitutively, and the hygromycin phosphotransferase (hph), which confers hygromycin B resistance and is driven by the CaMV 35S promoter for selection. The bombarded calli were selected on medium containing 30 mg/L Hygromycin B for 9 to 21 days, and subcultured to intermediate medium (1.0mg/L 2,4-D and 0.5 mg/L BAP), followed by regeneration media (1.0-3.0 mg/L BAP). Thirty hygromycin B resistant calli regenerated and 5 died in magenta box. Thirty five putative transgenic plants derived from 25 calli grew in soil and were harvested. Some plants tested by polymerase chain reaction (PCR) tested positive with primers for pinA and hph. Southern blots were performed to detect the presence of hph in T1 barley genomic DNA but were negative. Northern blots performed to detect the presence of pinA and hph transcribed RNA in the T1leaf tissue were also negative, showing that no stably transformed plants were obtained.Item Wheat puroindolines interact to control grain hardness and effect ruminal digestability of starch in cattle(Montana State University - Bozeman, College of Agriculture, 2005) Swan, Catlynn Gail; Chairperson, Graduate Committee: Michael J. Giroux.Endosperm texture directly affects end-use and milling qualities of hexaploid wheat. Genetically, the Hardness (Ha) locus controls the majority of endosperm texture variation and contains the puroindoline a (pina) and b (pinb) genes. Soft kernel texture results from both puroindolines being in the wild-type form, while hard wheats have a mutation in either puroindoline. Molecularly, grain texture is regulated by the starch surface protein complex friabilin, consisting primarily of the two proteins, puroindoline A (PINA) and B (PINB). Recent studies suggest that grain hardness is correlated with the presence of both functional PINA and PINB, not total puroindoline content. In addition, endosperm texture amongst cereal grains seems to play a major role in the speed and location of starch degradation in ruminants. The site of starch digestion along the gastrointestinal tract alters the nature of digestive end products (volatile fatty acids in the rumen and glucose in the small intestine) and the efficiency of metabolic utilization by the ruminant. The objectives here were to investigate which puroindoline limits grain softness in soft wheats, determine the limit of grain softness reduction, and to investigate the effect of varying puroindoline content in wheat on the rate of starch digestion in the rumen of beef cattle. Lines containing only additional pina were on average 7.4 units harder in grain texture and had starch that digested up to 10.6% faster than lines containing only additional pinb. Transgenic lines containing additional pinb showed a 2.6 to 4.8 fold increase in both PINA and PINB as bound friabilin, while lines containing additional pina showed only an increase in PINA. Increased expression of puroindolines was correlated with a decreased rate of ruminal digestion and was independent of particle size. The results demonstrated that PINB limits the binding of PINA to starch and is the limiting factor in the reduction of grain softness in soft wheats, that the limit of grain softness has not been reached, and that puroindolines slow the digestion of wheat starch in the rumen. Overall, puroindolines are important proteins in wheat end-use quality and can be manipulated and studied by use of transformation and over-expression.Item Puroindolines : their control over wheat grain hardness and influence on milling and bread baking traits(Montana State University - Bozeman, College of Agriculture, 2004) Hogg, Andrew Charles; Chairperson, Graduate Committee: Michael J. Giroux.Wheat grain is sold based upon several physiochemical characteristics, one of the most important being grain texture. Grain texture in wheat directly affects many end use qualities such as milling yield, break flour yield, and starch damage. The Hardness (Ha) locus located on the short arm of chromosome 5D is known to control grain hardness in wheat. This locus contains the puroindoline a (pina) and puroindoline b (pinb) genes. All wheats to date that have mutations in pina or pinb are hard textured, while wheats possessing both the 'soft type' pina-D1a and pinb-D1a sequences are soft. Furthermore, it has been shown that complementation of the pinb-D1b mutation in hard spring wheat can restore a soft phenotype. Here, the first objective was to identify and characterize the effect the puroindolines have on grain texture independently and together. The second objective was to determine which milling bread baking characteristics are affected by the seed specific over-expression of puroindolines. To accomplish both of these objectives a hard red spring wheat, possessing the pinb-D1b mutation, was transformed with 'soft type' pina and pinb, creating transgenic isolines that have added pina, pinb, or pina and pinb.