Submitted to: APS Annual Meeting
Publication Type: Abstract Only
Publication Acceptance Date: 4/1/2008
Publication Date: 6/1/2008
Citation: Cheng, P., Chen, X. 2008. Molecular mapping of a gene for resistance to stripe rust in spring wheat cultivar IDO377s. APS Annual Meeting. Phyto 98:S38.
Technical Abstract: Stripe rust, caused by Puccinia striiformis f. sp. tritici, is one of the most important diseases on wheat worldwide. ‘IDO377s’, a hard white spring wheat cultivar, has been grown in the Pacific Northwest for many years because of its high level resistance to many races of the pathogen. To map and tag genes in IDO377s for stripe rust resistance, we made a cross between ‘IDO377s’ and ‘Avocet S’ (AVS), a susceptible genotype. Segregation analysis of 114 F3 lines from AVS/IDO377s revealed that a single dominant gene conferred resistance in the greenhouse seedling tests with races of PST-43 and PST-45 of the pathogen. Bulk segregant analysis identified several resistance gene analog polymorphism (RGAP) and simple sequence repeat (SSR) markers linked to the resistance gene. Amplifications of the 21 nulli-tetrasomic lines of ‘Chinese Spring’ with some of the RGAP markers placed the resistance gene in IDO377s on the long arm of chromosome 2B. The chromosomal location of the resistance gene was further confirmed by SSR markers specific to the chromosomal arm. Based on the chromosomal location and reaction to various races of the pathogen, the IDO377s gene is likely different from all previously reported genes for resistance to stripe rust. A total of 108 wheat breeding lines and cultivars with or without IDO377s in their pedigree were used to validate the tightly linked molecular markers and to determine polymorphisms of the marker loci in various wheat genotypes.