Project Number: 2090-21000-033-00-D
Project Type: In-House Appropriated
Start Date: Mar 7, 2018
End Date: Mar 6, 2023
The long-term objective of this project is to improve the resilience of wheat plants under environmental stress. Specifically, during the next five years we will focus on the following objectives. Objective 1. Genetically improve soft white winter and club wheat for environmental resilience, disease resistance, and end-use quality. Subobjective 1A: Develop and release club (Triticum aestivum ssp. compactum) wheat cultivars with resistance to major regional diseases and adaptation to diverse environments in the western U.S. Subobjective 1B: Select breeding lines with better end-use quality and high Falling Numbers (FN) due to preharvest sprouting (PHS) and late maturity alpha-amylase (LMA) resistance. Subobjective 1C: Select soft white wheat breeding lines using indirect selection based on high throughput phenotyping (HTP) targeted to specific combinations of climate variables. Objective 2. Identify genetic resources and introgress multiple genes for resistance to stripe rust and to soil borne diseases into wheat germplasm. Subobjective 2A: Identify novel genetic resources with resistance to stripe rust and soil borne disease and identify loci controlling this resistance. Subobjective 2B: Introgress novel sources of resistance to stripe rust and soil borne disease from landraces into adapted wheat germplasm. Subobjective 2C: Conduct collaborative pre-breeding to introgress disease resistance from multiple germplasm accessions into adapted germplasm. Objective 3. Develop, evaluate, and use genotyping technologies and sequence information to increase knowledge of basic genetic processes controlling environmental resilience, disease resistance, and end-use quality in wheat and barley. Subobjective 3A: Identify genetic and molecular mechanisms that regulate response to low temperatures. Subobjective 3B: Identify genetic and molecular mechanisms controlling seed dormancy, germination, and resistance to preharvest sprouting. Subobjective 3C: Identify genetic and molecular mechanisms causing late-maturity alpha amylase expression during grain development. Subobjective 3D: Identify genetic mechanisms for resistance to disease. Objective 4. Incorporate genomic data in wheat and barley selection strategies by collaborating with regional breeding programs. Subobjective 4A: Develop molecular methods for use in genome wide association (GWAS), genomic selection, and transcriptomic strategies to evaluate wheat and barley germplasm. Subobjective 4B: Develop bioinformatic pipelines to facilitate use of genomic data in wheat and barley improvement. Subobjective 4C: Provide genomic and phenotypic data to Western Regional and U.S. Wheat and Barley improvement programs.
Subobjective 1A: Doubled haploids, genomic selection, and high throughput phenotying are used to increase gains from selection targeted to dry or high rainfall environments in the USDA-ARS club wheat breeding program. Subobjective 1B: Selection for preharvest sprouting and late maturity alpha-amylase resistance based on phenotypic and genotypic data identifes wheat breeding lines with stable high falling number. Tools and tests are developed to detect low falling number wheat, and to distinguish between late maturity alpha amylase and preharvest sprouting. Controlled environment and field-based screening systems are optimized. Plant genetic, biochemical and physiological components associated with low falling numbers are investigated, including the protein biochemistry of alpha amylase, and hydrolytic enzymes expressed during wheat grain development and gation. Subobjective 1C: Genomic selection, high throughput phenotyping and meta-environmental analylsis are used to increase the accuracy breeding program data. Genome estimated breeding values are calculated for soft white and club wheat. Subobjectives 2A and 2B: Dominant male sterility, marker-assisted selection and phenotypic selection are used to incorporate new sources of resistance to stripe rust and to soil borne disease into adapted backcross populations of wheat.Subobjective 2C: F4 bulk populations are developed and selected for adult plant resistance to stripe rust in collaboration with U.S. wheat breeders, followed by selection for agronomic traits and re-evaluation for resistance. Subobjective 3A: Genes, identified from expression studies that contribute to low temperature tolerance, are combined to increase the level of low temperature tolerance in wheat. Subobjective 3B: Preharvest sprouting resistance is increased when mutant alleles associated with altered hormone sensitivity are combined to provide increased seed dormancy. Markers linked to emergence traits are developed. Subobjective 3C: A genome wide association study for resistance to late maturity alpha amylase is conducted, near isogenic lines differing for susceptibility loci are developed and breeding populations are screened in collaboration with wheat breeders. Subobjective 3D: The functional gene for stripe rust resistance is identified using a knock out of that resistance in an EMS-mutagenized population. Subobjective 4A: Targeted amplicon sequencing of at least 1500 known informative markers that are important for selection in western U.S. breeding programs is used to genotype breeding lines. Subobjective 4B: Software tools are developed to apply genomic data to crop improvement. Subobjective 4C: Genomic and phenomic data are provided to public and private sector participants in the Western Regional Cooperative Nurseries and the Western Regional Small Grains Genotyping Laboratory.