Submitted to: American Phytopathological Society Abstracts
Publication Type: Abstract Only
Publication Acceptance Date: 5/1/2007
Publication Date: 7/1/2007
Citation: Chen, X., Lin, F. 2007. Identification and molecular mapping of genes for all-stage and high-temperature adult-plant resistance to stripe rust in ‘Express’ wheat. American Phytopathological Society Abstracts, San Diego, CA, 7/28-8/2/07, 97:S21.
Technical Abstract: Wheat cultivar ‘Express’ has race-specific all-stage (also called seedling) resistance and non-race-specific high-temperature adult-plant (HTAP) resistance to stripe rust caused by Puccinia striiformis f. sp. tritici (PST). To identify and map the resistance genes, Express was crossed with 'Avocet Susceptible' (AVS). The parents and F1, F2, F3, and F5 progenies were evaluated at the seedling stage under the controlled greenhouse conditions for all-stage resistance with four selected races. A total of 146 F5 and their F6 lines were evaluated for HTAP resistance in field plots in 2005 and 2006, respectively, under natural infection of the stripe rust populations virulent on seedlings of Express. The resistance gene analog polymorphism (RGAP) and simple sequence repeat (SSR) techniques were used to identify markers for mapping the resistance genes for all-stage resistance and quantitative trait loci (QTL) for HTAP resistance. Genetic analysis showed that Express has two dominant genes for all-stage resistance. The gene for resistance only to races PST-1 and 21 was mapped on chromosome 1BL and the gene resistant to PST-1, 21, 43, and 45 was mapped on chromosome 5BL. Three QTL for HTAP resistance were mapped on chromosomes 6AS, 3BL, and 1BL. These genes (QTL) are distinct from previously report genes and should be useful in developing cultivars with durable resistance.