1a. Objectives (from AD-416):
The purpose of this project is to develop and deploy effective stripe rust resistance genes in the next generation of U.S. barley varieties, including germplasm from the ARS-Aberdeen breeding program. In this project we have developed the following objectives: 1. Use current barley stripe rust resistance QTL alleles via marker assisted selection (MAS). a. We will transfer BISON resistance alleles to winter malting 2-rows, winter food 2-rows and winter food 6-rows and OR71 resistance alleles to Nebraska cold tolerant germplasm. 2. Discover new resistance QTLs/genes. a. We will leverage T-CAP association mapping (AM) results for barley stripe rust (BSR) resistance. 3. Confirm, validate, and identify resistant germplasm in addition to OSU program. a. We will expand our screening of USDA-ARS germplasm for resistance at Corvallis.
1b. Approach (from AD-416):
Use current alleles via MAS: We will leverage genotyping services provided by the Triticeae-CAP (T-CAP) project at the USDA Regional Lab, Pullman. In collaboration with Deven See at this facility, we have developed Sequenom assays to characterize stripe rust resistance haplotypes in the following germplasm: (i) doubled haploid (DH) lines derived from crosses of European winter 2 –rows and the BISON, (ii) F4 head rows derived from crosses of BISON resistance with hull-less food types, and (iii) BC1 progeny derived from crosses with Nebraska cold tolerant germplasm. The resistance haplotypes will be validated using field resistance data and used for marker assisted selection (MAS). Discover new resistance QTLs/genes: We will leverage T-CAP Association Mapping (AM) for BSR resistance in the national collection. This germplasm resource will be phenotyped and genotyped in 2012 via T-CAP. Based on the AM, with support from this SCA and in collaboration with personnel at Aberdeen, in the Fall 2012 we will initiate crossing to introgress new QTL alleles/genes into adapted winter germplasm. Confirm, validate, and identify resistant germplasm in addition to OSU program: Because barley stripe rust is not endemic at Aberdeen, Idaho, we will expand our screening of USDA-ARS germplasm for resistance at Corvallis. This will be accomplished by fall-planting in 2011 to ensure optimum epidemic development in spring, 2012. Dissemination and publication: All germplasm will be publicly available: We will prepare and/or co-author peer reviewed publications with USDA-ARS scientists at Aberdeen, Idaho.
3. Progress Report:
This project relates to the parent project’s Objective 2: “Develop methods to facilitate accelerated breeding for adaptive traits and utilization of germplasm diversity in barley and oat.” In 2012, we made 50 crosses between elite winter barleys and stripe rust resistance donors (the germplasm “Full Pint” and the BISON lines) with mapped stripe rust resistance genes. The F1 seed from these crosses was used to develop 900 doubled haploid lines, 817 of which are now in field trials and the remaining 93 are ready for fall planting. In addition to these lines, 650 new lines are currently growing in the greenhouse and another 100 are currently in tissue culture. Also, in cooperation with ARS scientists at Pullman, Washington, we are also developing molecular assays to improve our ability to select for stripe rust resistance. These efforts should speed incorporation of stripe rust resistance into elite malting barley varieties adapted for growing in the Pacific Northwest, including Idaho. We are also using a new technique called genome wide association mapping to learn more about the genetics of stripe rust resistance in a diverse set of barley generated through the Triticeae Coordinate Agricultural Project (TCAP). Nearly 1400 of these TCAP barley lines are currently in the field for stripe rust testing and will be rated for stripe rust reaction in May/June 2013. These lines will be ‘genotyped’ using the Illumina 9K SNP chip. The genotype and phenotype data will be used to find association between the SNP markers and stripe rust resistance in an effort to discover novel resistance within the set of barley lines. During 2013 we expanded our stripe rust screening of USDA-ARS germplasm at Corvallis. Two mapping populations Lenetah/GZ (154 lines + parents) and Charles/95SR316A (190 lines + parents) are currently in field trials and will be rated for stripe rust in May/June. Flowering time data have been recorded on these populations so that maturity can be taken into account when mapping resistance QTLs/genes. Through this effort we aim to identify 1) markers that will enable breeders to more easily incorporate resistance into their lines and 2) new winter malting and spring feed barley lines that have stripe rust resistance and that can be used in further breeding work.