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Item Consider the roots: examining barley belowground in the search for adaptation(Montana State University - Bozeman, College of Agriculture, 2024) Williams, Jessica Lynn; Chairperson, Graduate Committee: Jamie Sherman; This is a manuscript style paper that includes co-authored chapters.Barley is important for global food security and sustaining the economically valuable malt industry. Montana is a top barley producer in the United States, but terminal drought stress poses a significant threat to this production by negatively impacting yield and quality. New crop varieties with enhanced environmental adaptation and soil resource extraction would help address this and other issues facing modern agriculture. Stay-green is a trait that extends grain fill in cereals and can stabilize yield and quality under drought. However, this trait and its benefits can be inconsistent across environments and its successful incorporation into breeding strategies would benefit from expanded understanding of stay-green. Roots may play a role in stay-green physiology. Roots provide plants with the water and nutrients needed for growth and are important for crop performance in their own right. Different root system architectures provide adaptation to different environmental stressors, but studying these belowground structures is challenging. Adaptation is also impacted by soil properties and microbial communities. For this dissertation, roots were examined in greenhouse seedling assays and field trials in Montana. Agronomic performance was also assessed for malt barley and spring wheat cultivars varying for stay-green, a biparental barley population segregating for stay-green, and a diverse mapping population of barley lines from different breeding programs. Stay-green cultivars had a greater percentage of deep roots, more prolonged root growth during grain fill, and greater yield. Analysis of the biparental population identified genetic co-segregations of stay-green, root phenotypes, grain quality, and quality stability between environments, further supporting the benefit of stay-green in dry environments and its connection to roots. The diverse mapping population was used to find associations between the relative abundances of bacteria in the rhizosphere and barley genetic loci, that were mostly environment specific. Rhizospheric bacteria may be involved in local adaptation of plants. Finding plant genetic signal for these microbial characteristics supports the idea that it may be possible to breed crops with enhanced ability to recruit beneficial microbiomes if environmental influence and agronomic impact can be understood. Root examination remains a challenging but worthwhile avenue to pursue in crop adaptation research.Item Leveraging a global spring, 2-row barley population to accelerate the development of superior forage barley varieties for Montana growers(Montana State University - Bozeman, College of Agriculture, 2021) Hoogland, Traci Janelle; Chairperson, Graduate Committee: Jamie ShermanAs more people around the globe escape poverty, they are eating more meat and dairy products. To support this increased demand for animal products there is an urgent need to develop more sustainable high-quality forage and hay crops for the livestock production industry. Barley (Hordeum vulgare spp. vulgare L.) is considered one of the most drought tolerant of the annual cereals and spring barley has been shown to out yield established perennial forages under drought conditions in central Montana (Cash, Surber, & Wichman, 2006). To accelerate the development of superior forage barley varieties for Montana, the following goals were identified 1) Utilize a genome wide association analysis to find genetic regions related to key forage and agronomic traits, 2) Use statistical modeling to a) examine the relationship between difficult to measure forage traits such as quality and yield, and easy to measure agronomic traits such as flowering time and plant height, b) identify agronomic traits that can be used as proxies for yield and quality in the earliest stages of the breeding program when genetic and phenotypic variability are at their greatest. Through these techniques the importance of variation in timing of plant maturity was identified. Statistical modeling showed that variability in forage yield and quality was observed to be closely related to variability in the timing of heading and soft-dough dates. Plant height was also determined to be of importance especially for biomass yield. Through genome-wide association analysis, novel QTL were discovered in relation to all studied traits. QTL were detected on all seven chromosomes and the majority of forage trait QTL co-located with QTL related to the timing and progression of plant development and maturity. This appeared to indicate that in a population of global barley accessions, the loci with the greatest impact on forage traits may be those containing genes regulating plant development and senescence. This further strengthened the evidence from the modeling study that a relationship exists between the two trait categories: traits for measuring the timing of plant development and forage traits.Item Corn versus barley in beef cattle finishing diets: effect on steer performance, feeding behavior, and ruminal environment(Montana State University - Bozeman, College of Agriculture, 2021) DelCurto-Wyffels, Hannah Margaret; Chairperson, Graduate Committee: Megan Van Emon; Julia M. Dafoe, Cory T. Parsons, Darrin L. Boss, Timothy DelCurto, Samuel A. Wyffels, Megan L. Van Emon and Janice G. P. Bowman were co-authors of the article, 'Corn versus barley in finishing diets: effect on steer performance and feeding behavior' in the journal 'Animals' which is contained within this dissertation.; Julia M. Dafoe, Cory T. Parsons, Darrin L. Boss, Timothy DelCurto, Samuel A. Wyffels, Megan L. Van Emon and Janice G. P. Bowman were co-authors of the article, 'The influence of environmental conditions on intake behavior and activity by feedlot steers fed corn or barley-based diets' in the journal 'Animals' which is contained within this dissertation.; Hannah M. DelCurto-Wyffels, Julia M. Dafoe, Cory T. Parsons, Darrin L. Boss, Timothy DelCurto, Samuel A. Wyffels, Megan L. Van Emon and Janice G. P. Bowman were co-authors of the article, 'Diurnal ruminal pH and temperature patterns of steers fed corn or barley-based finishing diets' in the journal 'Animals' which is contained within this dissertation.While corn is the most common feed ingredient in the United States, barley, which is more suitable for the growing and climatic conditions at northern latitudes, can be a common feed alternative to corn. The different digestive utilization of unique feedstuffs coupled with extreme environmental conditions can pose challenges to efficiently feeding cattle in different climates. Thus, to further our understanding of the use of barley in feedlot diets at northern latitudes this study evaluated the effects of barley and corn finishing rations on feedlot performance, feeding behavior, and ruminal environment. For two consecutive years, Angus-based yearling steer calves were fed in a feedlot trial (427.3 + or - 3.7 kg; n = 48 in year 1, and 406.8 + or - 3.4 kg; n = 47 in year 2). Steers were randomly assigned to one of two primary basal grain dietary treatments: 1) Number 2 feed corn or 2) Hockett barley. Steers were fed in a GrowSafe system to measure individual animal intake and behavior throughout the duration of the study. Twelve steers per treatment group for each year of the study were also fitted with a HOBO pendent G accelerometer to measure activity and a SmaXtec ruminal bolus for continuous rumen monitoring of temperature and pH. Limited differences were observed in regard to performance and eating behavior of steers fed corn or barley-based diets. The steer's diet interacted with short term environmental changes to influence animal feeding behavior, but diet had limited impact on cattle lying activity. Continuous ruminal monitoring revealed average daily ruminal pH and temperature were not impacted by diet; however, diet did affect daily variation in ruminal pH and temperature. Intake patterns were also different between corn and barley-fed steers in which corn-fed steers consumed more feed the first 6 hours directly after feeding while barley-fed steers consumed more feed later in the day. Presumably, these intake patterns could be influenced by differences in diurnal patterns of ruminal pH between corn and barley. Depending on cost and production year, both barley and corn can be high quality feedstuffs to use in beef cattle finishing rations.Item Genetics of seed dormancy in wheat and barley(Montana State University - Bozeman, College of Agriculture, 2020) Vetch, Justin Michael; Chairperson, Graduate Committee: Michael J. Giroux; Robert N. Stougaard, John M. Martin and Michael J. Giroux were co-authors of the article, 'Revealing the genetic mechanisms of preharvest sprouting' in the journal 'Plant science' which is contained within this dissertation.; Robert N. Stougaard, John M. Martin and Michael J. Giroux were co-authors of the article, 'Allelic impacts of TaPHS1, TaMKK3, and Vp1B3 on preharvest sprouting of northern Great Plains winter wheats' in the journal 'Crop science' which is contained within this dissertation.; Jason G. Walling, Jamie D. Sherman, John M. Martin and Michael J. Giroux were co-authors of the article, 'Mutations in the HvMKK3 AND HvAlaAT1 genes affect barley pre-harvest sprouting and after-ripened seed dormancy' in the journal 'Crop science' which is contained within this dissertation.; Philip L. Bruckner, John M. Martin and Michael J. Giroux were co-authors of the article, 'TAMFT homeologs are associated with preharvest sprouting winter wheat' submitted to the journal ''Crop science' which is contained within this dissertation.Montana producers have many biotic and abiotic stresses to contend with. One of interest to avoid is preharvest sprouting (PHS), which is the precocious germination of grains before harvest. PHS affected grain is discounted at the elevator, resulting in grain being unsuitable for many foods and direct losses to producers. PHS is not widespread every year in Montana but in some years causes large economic loss. Although PHS is a response to environmental cues it is largely controlled by genetics. Genes that control seed dormancy are the most likely candidate genes for PHS resistance and the series of studies presented in this dissertation examine the impact of several genes upon small grain PHS susceptibility. The studies used several methods to assess PHS susceptibility and determine which alleles of individual genes were present. The methods included seed dormancy screening assays, alpha amylase enzyme activity analysis, falling numbers analysis, genotyping by direct sequencing and via use of various markers, RNA-sequencing, and gene expression analysis. The first study served as a PHS susceptibility survey and provides PHS tolerance information on MT grown wheat varieties. This study also found that of the three most reported PHS associated genes (TaMFT 3A, TaMKK3 4A, and TaVp1 3B), only TaMFT 3A was associated with PHS in Montana winter wheats, even though the previously reported variation was observed in all three genes. The second study looked at PHS susceptibility among current and historically grown barley varieties. It was found that malt varieties vary greatly in their susceptibility to PHS with the top grown AMBA recommended varieties among the most susceptible. It was also found that a previously unstudied mutation in the HvMKK3 gene is associated with PHS susceptibility. Interestingly, HvMKK3 and HvAlaAT1 affect dormancy at different time points in grain maturity indicating dormancy may be tailored to a specific timeframe (high dormancy at harvest with rapid decay of dormancy after harvest). The final study revisited winter wheat PHS and found that the TaMFT 3B and 3D homeologs are associated with PHS which has not been shown to date.Item Population dynamics of wheat stem sawfly, Cephus cinctus Norton, in barley in Montana(Montana State University - Bozeman, College of Agriculture, 2020) Achhami, Buddhi Bahadur; Chairperson, Graduate Committee: David K. Weaver; Gadi V. P. Reddy, Jamie D. Sherman, Robert K. D. Peterson and David K. Weaver were co-authors of the article, 'Antixenosis, antibiosis, and potential yield compensatory responses in barley cultivars exposed to wheat stem sawfly under field conditions' which is contained within this dissertation.; Gadi V. P. Reddy, Jamie D. Sherman, Robert K. D. Peterson and David K. Weaver were co-authors of the article, 'Effect of precipitation and temperature on larval survival of Cephus cinctus (Hymenoptera: Cephidae) in barley cultivars' which is contained within this dissertation.; Robert K. D. Peterson, Jamie D. Sherman, Gadi V. P. Reddy and David K. Weaver were co-authors of the article, 'Multiple decrement life tables of Cephus cinctus Norton (Hymenoptera: Cephidae) across a set of barley cultivars: the importance of plant defense versus cannibalism' which is contained within this dissertation.; Gadi V. P. Reddy, Megan L. Hofland, Robert K. D. Peterson, Jamie D. Sherman and David K. Weaver were co-authors of the article, 'Host selection and oviposition behaviors of Cephus cinctus (Hymenoptera: Cephidae) in barley' which is contained within this dissertation.Wheat stem sawfly (WSS) is an economically devastating pest of cereals grown in North America. The larva is the only feeding stage and remains confined within a host stem until it emerges as an adult the following year. This limited mobility increases larval vulnerability to mortality factors when host plant traits are hostile to survival. For instance, larval mortality is greater in barley than in solid stemmed wheat cultivars known to be resistant. Both solid stemmed wheat and barley kill neonates via host plant resistance traits. Traditionally, barley was recommended as an alternative rotational crop to prevent WSS outbreaks in wheat crops. There is limited data available regarding barley host plant resistance and questions persist. Has barley resistance changed over time? What is the impact of larval feeding injury on grain yield of barley? Do females display similar oviposition behaviors across barley cultivars that vary in susceptibility? To answer these questions. I conducted field experiments to assess resistance and possible tolerance to WSS in eight barley cultivars. Based on the number of eggs, 'Hockett' was the most attractive cultivar to WSS female (less antixenosis), while 'Craft' and 'Celebration' killed the greatest number of neonates due to antibiosis. Multiple decrement life table studies revealed that plant defense and cannibalism were two major causes of larval mortality. We measured greater yield in infested stems with dead larvae (potential tolerance) than for cut stems and both were greater than uninfested stems in all cultivars except 'Celebration'. A greenhouse study revealed that females preferred 'Hockett' over 'Craft' in frequencies of oviposition behaviors and numbers of eggs deposited. Additionally, a greater amount of the WSS attractant (Z)-3-hexenyl acetate was found in aerations from 'Hockett' plants than from 'Craft.' The amount of defensive compound linalool was greater in aerations from 'Craft' than from 'Hockett.' These results suggest that barley cultivars are equipped with varying levels of antibiosis, antixenosis, and tolerance traits against WSS. Thus, we can exploit these traits in the development of cultivars which can reduce WSS populations and decrease economic loss caused by this species.Item Improving malt barley agronomics via allelic selection of senescence and flowering time controlling genes(Montana State University - Bozeman, College of Agriculture, 2020) Alptekin, Burcu; Chairperson, Graduate Committee: Andreas M. Fischer; Dylan Mangel, Duke Pauli, Tom Blake, Jennifer Lachowiec, Traci Hoogland, Andreas Fischer and Jamie Sherman were co-authors of the article, 'Combined effects of glycine-rich RNA binding protein and a NAC transcription factor extend grain fill duration and improve malt barley agronomic performance' submitted to the journal 'Theoretical and applied genetics' which is contained within this thesis.; Dylan Mangel, Duke Pauli, Tom Blake, Jennifer Lachowiec, Jamie Sherman and Andreas Fischer were co-authors of the article, 'Dissecting the effects of senescence-regulating HvNAM1 and HvNAM2 transcription factors on malt barley agronomics' submitted to the journal 'Molecular breeding' which is contained within this thesis.; Dylan Mangel, Duke Pauli, Tom Blake, Hannah Turner, Jennifer Lachowiec, Jamie Sherman and Andreas Fischer were co-authors of the article, 'Allelic selection of senescence and flowering time controlling genes confers malt extract stability' submitted to the journal 'Journal of the American Society of Brewing Chemists' which is contained within this thesis.Malt barley (Hordeum vulgare L.) is a high-profit crop for farmers; yet, its production raises challenges that need to be addressed. The standards for grain quality in malt barley are stringent, and the rejection of non-qualified grains by maltsters is the leading cause of revenue loss for malt barley producers. Rejection is mainly due to high grain protein content and low kernel plumpness which both cause significant problems in the malting process. While proper growing practices can improve malt quality, the industry requires genotypes that have more stable malt quality. Therefore, understanding the molecular mechanisms associated with grain quality can be applied to improve selection of superior malt varieties. A considerable volume of literature has suggested that regulation of whole-plant senescence and flowering processes in cereals have direct influences on grain yield and quality parameters. The central question in this dissertation examined whether malt barley agronomic and end use quality can be improved by the selection of varying alleles for genes associated with plant development. With this purpose, two whole-plant senescence-regulating NAM, ATAF and CUC (NAC) transcription factors, HvNAM1 and HvNAM2, and a flowering-time controlling Glycine-Rich RNA Binding Protein (HvGR-RBP1) were studied. Molecular markers for selection of alleles from varieties 'Karl' (with consistently low grain protein) and 'Lewis' were developed, and an advanced-generation malt barley breeding population was genotyped. Statistical analysis of growth parameters from this population showed that selection of HvNAM1 'Karl', HvNAM2 'Karl' and HvGR-RBP1 'Lewis' alleles ensures a longer grain filling period in malt barley. Plants with prolonged grain filling also exhibited increased kernel plumpness and test weight. Additionally, selection of 'Karl' alleles for both NAC genes decreased grain protein content ensuring grain quality for malting. The improvement of grain characteristics correlated with improved malt phenotypes, for example a ~2% increase in malt extract, and improvement in other malt characteristics such as beta-glucan content and alpha-amylase activity was observed. Overall, these data show that molecular genetics and allelic selection for genes controlling plant development is promising for advancing malt quality. Research performed here has a direct potential for improving the profits for malt barley producers.Item Evaluation of wheat production practices under wheat streak mosaic disease risk and wheat stem sawfly pressure in Montana(Montana State University - Bozeman, College of Agriculture, 2020) McKelvy, Uta; Chairperson, Graduate Committee: Mary Burrows; Monica Brelsford, Jamie Sherman and Mary Burrows were co-authors of the article, 'Susceptibility and tolerance of winter wheat, spring wheat and barley cultivars to mechanical inoculation with wheat streak mosaic virus' submitted to the journal 'Plant health progress' which is contained within this dissertation.; Peggy Lamb, Monica Brelsford and Mary Burrows were co-authors of the article, 'Impact of planting date, seeding rate and cultivar choice on spring and winter wheat productivity and profitability in Montana' submitted to the journal 'Agronomy journal' which is contained within this dissertation.; David Weaver and Mary Burrows were co-authors of the article, 'Evaluation of chemical and cultural management practices for wheat stem sawfly control and effects on beneficial insects in spring wheat in Montana' submitted to the journal 'Journal of economic entomology' which is contained within this dissertation.Wheat (Triticum aestivum L.) is an economically important crop for Montana's agricultural industry. Wheat streak mosaic (WSM) is an important viral disease in Montana and the wheat stem sawfly (WSS; Cephus cinctus Norton) is a major insect pest in the state. Understanding these disease and pest problems and the factors that promote and suppress disease and pest pressure forms the foundation for a successful integrated pest management program. In this dissertation, we evaluate wheat production practices in Montana and provide information on the effectiveness and implications of cultural and chemical management practices in mitigating WSM disease and WSS pressure. We assessed the tolerance of popular winter wheat, spring wheat, and barley cultivars in Montana to mechanical inoculation with WSMV in field studies. Winter wheat 'Brawl CL Plus' and breeding lines CO12D922 and MTV1681 demonstrated moderate WSMV incidence and minor yield penalties under WSMV inoculation, making them suitable cultivars to be grown in high-risk environments. We investigated the effects of cultivar choice, planting date, and seeding rate on grain yield and quality parameters in field studies. Our results validated current planting date recommendations for Montana. Yield reductions were observed at planting dates later than mid-September and April for winter wheat and spring wheat, respectively. No yield increase was observed when winter wheat was planted before mid-September. No meaningful and reliable economic benefits were associated with an increase in seeding rate beyond the recommended density. We developed a WSM risk prediction model and released it as the online learning tool AWaRe ('Assessment of Wheat streak mosaic Risk'). AWaRe presents the first learning tool that integrates complex information on the dynamics underlying WSM disease and relates them to the user in an interactive way. We expect the adoption of risk assessment based WSM management practices that result in a reduced economic impact through the use of this tool. The potential of different insecticides to manage WSS damage was compared to spring wheat genotypes with varying degrees of WSS resistance. Results showed that application of the systemic insecticide Thimet-20G provided effective protection of susceptible cultivar 'Reeder,' but use of solid-stem cultivars were similarly effective.