Research Project: Improvement of Barley and Oat for Enhanced Productivity, Quality, and Stress Resistance

Location: Small Grains and Potato Germplasm Research

2021 Annual Report

Objectives
This project intends to produce improved barley and oat germplasm, and new information and techniques to facilitate increased efficiencies. The objectives below will be the specific focus for the next five years: Objective 1: Develop barley and oat germplasm with increased yield, better quality, and superior or novel resistances to biotic and abiotic stresses. • Subobjective 1A: Develop low protein barley lines suitable for all-malt brewing. • Subobjective 1B: Develop improved winter food barley varieties. • Subobjective 1C: Develop facultative malting barley. • Subobjective 1D: Develop barley varieties with improved Fusarium head blight resistance. Objective 2: Translate new, sequence-based information into breeder-friendly tools for crop improvement in barley and oats. • Subobjective 2A: Map Fusarium head blight (FHB) resistance and develop germplasm resistant to multiple diseases via marker-assisted selection. • Subobjective 2B: Map quantitative trait loci (QTL) from new sources of adult plant resistance to oat crown rust disease (OCR) and develop milling oat germplasm resistant to crown rust. Objective 3: Develop and implement novel biotechnological tools to produce barley germplasm with unique traits and enhance understanding of the genetic mechanisms underlying key traits. Subobjective 3A: Deliver a site-specific recombination (TAG) platform via Ds-mediated transposition, and demonstrate functionality for RMCE in barley. • Subobjective 3B: Construct and deliver Ds-bordered RNAi constructs that are transposition competent and that confer resistance to Fusarium head blight. • Subobjective 3C: Perform genetic analyses of seed total phosphorus and phytic acid in barley.

Approach
Objective 1: Productive varieties will be developed that are improved for agronomic performance, protein and beta-glucan contents, winter survival, and Fusarium head blight (FHB) resistance. Hybridization with generation advance in greenhouses, New Zealand, and by doubled haploids will be used for population development. Breeding efficiency will be enhanced by investigating the genetics of key traits to enable genomic selection and the development of novel selection schemes. Agronomic performance and FHB resistance will be assessed in multi-location field trials. Grain quality will be assessed by physical examination and chemical analysis of grain for malt quality, protein and beta-glucan contents, and mycotoxin content. Objective 2: Research will relate genetic sequence to disease resistance. Incorporating resistance to diseases that constrain oat and barley production outside of the Intermountain West will make Aberdeen germplasm more valuable. Since Idaho locations have low disease, direct selection for resistance is difficult. Indirect selection of sequence-based markers associated with resistance will combine good agronomic performance and grain quality with resistance to rusts and blotches. For diseases with established markers, development of new lines with specific markers will precede field screening in disease-prone sites outside of Idaho and in greenhouses using artificial inoculation. For other diseases, such as oat crown rust, screening in disease-prone sites will measure disease in multiple test lines, and statistical associations between specific sequences and resistances will identify and “map” new markers. Hybridization, generation advance, and genotypic and phenotypic screens will establish new populations from which lines that have improvements in disease resistance, yield, and quality will be selected. Objective 3: Research will develop tools for experimental genetic manipulations and knowledge of how phosphorus is stored in seeds. Phosphorus is a critical nutrient and a major water pollutant. The hypothesis that the gene lpa-M955 is responsible for reduced seed phosphorus will be investigated by investigating statistical associations between the gene and different levels of seed phosphorus as measured by chemical assays. The hypothesis that new mutations can be found that result in 25% less phosphorus but without negative impact on plant performance will be examined by finding low-phosphorus mutant seeds, and growing them and selecting healthy plants that will then be tested in greenhouses and fields. To facilitate future genetic engineering experiments to identify additional genes of importance, the hypothesis that causing test genes to “jump” (transpose) into specific locations will help answer genetic questions will be tested by attempts to move a test gene into a specially designed receiver site. To test the hypothesis that this process can be harnessed to produce a non-chemical method of controlling a fungus that produces toxins in crop seeds, transposition will deliver an antifungal gene, followed by greenhouse and growth chamber screening for the reduced ability of the fungus to grow and produce toxins.

Progress Report
Barley breeding lines were evaluated in multiple nurseries, crosses were made in the greenhouse, and a New Zealand nursery was included to speed up the breeding process. In support of Sub-objective 1A, research continued on spring (13ARS183-9) and winter elite malting (11ARS537-19) lines that were approved by the American Malting Barley Association (AMBA) for Plant scale tests in 2021. Breeding line 11ARS162-4 qualified for industrial scale testing after two years of satisfactory pilot scale tests. We provided over 300 pounds of 11ARSA162-4 for a malting company to conduct the testing in 2021. In addition, we provided 10 pounds of 11ARS162-4 for another malting company for their testing. To address the specific needs of the all-malt brewing industry, we continued the low protein line characterization. Barley lines showed different responses to water stress in their leaf nitrogen content, grain nitrogen content, and grain protein levels. Results have been accepted for publication in the Journal of Agronomy and Crop Science. In support of Sub-objective 1B, we identified a new winter food barley elite line of 12ARS777-2, which showed competitive yield potential compared with the Upspring variety, and greatly improved beta glucan quality. In support of Sub-objective 1C, research continued on the advancement of populations derived from the crosses involving at least one facultative parent. Some promising lines were identified in the winter performance nurseries. Their performance in spring nurseries will be tested in 2021. To address the growing problem of Fusarium head blight (FHB) in the Intermountain West (Sub-objective 1D), we implemented routine screening for resistance in the breeding materials and have identified FHB resistant elite breeding lines. The updated results have been shared with stakeholders and other researchers, and some of these lines have been requested by other scientists. The spring malting barley genomic selection training population has been evaluated for FHB resistance at multiple locations and markers associated with resistance have been identified. An additional year of data will be used to validate these markers. Other molecular markers were used to guide the selection of parents in crosses made to increase the frequency of desirable agronomic performance alleles while maintaining diversity for malt quality quantitative trait loci in the breeding program. Towards the goal of introgressing foliar disease resistance into FHB-resistant barley germplasm (Sub-objective 2A), bi-parental mapping populations (95SR316A/Conlon, 95SR316A/ND Genesis, ND Genesis/2Ab08-X05M010-82 and 2Ab08-X05M010-82/Conlon) have been genotyped and planted in disease evaluation nurseries in order to gather data for mapping genes influencing FHB and net blotch disease resistance. Winter malting barley breeding lines 06ARS789-34 and 10ARS523-3 were crossed with elite winter barley cultivars. These populations will be used to map disease resistance in the winter barley germplasm. In support of Sub-objective 2B, research continues on oat populations incorporating new sources of adult plant resistance to oat crown rust disease that have been advanced by single-seed descent to the F5 generation (resistant parents CIav 2272, PI 140903, PI 237090). These are ready for gene mapping and selection of resistant lines for further breeding work. Other populations under development include those incorporating new sources of resistance (PI 287296, PI 285583, and PI219765) and those made with established sources of resistance in order to determine if resistance is unique. In support of Objective 3, research continues on Barley Ds transposon tagged lines with distinct integration sites already developed, which were evaluated against the Golden Promise genome sequence. The chromosome locations of Ds insertions were identified for 91 lines. In support of Sub-objective 3B, collaborative work was successful in developing and validating an agrobacterium-mediated transformation method using excised Gemcraft barley embryos. Fusarium graminearum genes putatively involved in the biosynthesis of mycotoxin were identified and for one of these, T, a vector containing double-stranded Tri6-targetting RNA was constructed and introduced into the Gemcraft variety genome. Eleven T0 transgenic plants have been generated and confirmed by selection markers to express the Tri6 vector. Descendants of these plants will be used to demonstrate the influence of this double-stranded RNA on FHB infection and mycotoxin production.

Accomplishments

Review Publications
Hu, G., Evans, C.P., Satterfield, K.L., Ellberg, S. 2021. Registration of spring malting barley germplasm of ARS84-27, ARS98-31, and ARS10-82. Journal of Plant Registrations. 15(2):345-350. https://doi.org/10.1002/plr2.20114.
Liang, X., Hu, G., Satterfield, K.L., Evans, C.P., Jiang, W. 2021. Variation in grain protein and leaf nitrogen in diverse spring barley genotypes. Journal of Agronomy and Crop Science. https://doi.org/10.1111/jac.12500.
Huang, C., Esvelt Klos, K.L., Huang, Y. 2020. Genome-wide association study reveals the genetic architecture of seed vigor in oats. G3, Genes/Genomes/Genetics. 10(12):4489-4503. https://doi.org/10.1534/g3.120.401602.
Zimmer, C.M., McNish, I.G., Esvelt Klos, K.L., Oro, T., Arruda, K.M., Gutkoski, L.C., Pacheco, M.T., Smith, K.P., Federizzi, L.C. 2020. Genome-wide association for B-glucan content, population structure, and linkage disequilibrium in elite oat germplasm adapted to subtropical environments. Molecular Breeding. 40. Article 103. https://doi.org/10.1007/s11032-020-01182-0.