Submitted to: American Phytopathological Society Abstracts
Publication Type: Abstract Only
Publication Acceptance Date: 5/1/2007
Publication Date: 7/1/2007
Citation: Chen, X., Zhao, J. 2007. Identification of molecular markers for Yr8 and a gene for high-temperature, adult-plant resistance against stripe rust in the AVS/6*Yr8 wheat line. American Phytopathological Society Abstracts, San Diego, CA, 7/28-8/2/07, 97:S21.
Technical Abstract: Stripe rust, caused by Puccinia striiformis f. sp. tritici, is one of the most important diseases of wheat worldwide. The disease is preferably controlled by growing resistant cultivars. The AVS/6*Yr8 wheat line has Yr8 for race-specific all-stage resistance and was identified to have non-race specific high-temperature adult-plant (HTAP) resistance to stripe rust. To identify molecular markers for the resistance genes, 116 BC7:F3 lines from the 'Avocet Susceptible' (AVS)/'Compair' cross were evaluated at the seedling stage with races PST-17, PST-43, and PST-45 under controlled greenhouse conditions and at the adult-plant stages in the fields under natural infection of the rust population virulent on AVS/6*Yr8. The rust evaluations of the mapping population confirmed that the AVS/6*Yr8 lines has a single gene for all-stage resistance. The resistance gene analog polymorphism (RGAP) and simple sequence repeat (SSR) techniques were used to identify markers linked to the resistance genes. The results confirmed Yr8 on the long arm of chromosome 2D and mapped the HTAP resistance gene also on 2DL. The two genes were closely linked to each other with a genetic distance of 1.3 cM. The molecular markers should be useful in accelerating the introgression of the HTAP resistance gene into wheat cultivars and pyramiding these genes with other genes for durable resistance.