Quantitative trait loci for resistance against Yellow rust in two wheat-derived recombinant inbred line populations.

Yellow rust, which is a major disease in areas where cool temperatures prevail, can strongly influence grain yield. To control this disease, breeders have extensively used major specific resistance genes. Unfortunately this kind of resistance is rapidly lost due to pathogen adaptation. More-durable resistance against yellow rust can be achieved using quantitative resistance derived from cultivars with well-established durable resistance. The winter wheat Camp Remy has maintained a high level of resistance for over 20 years. In order to map quantitative trait loci (QTLs) for durable yellow rust resistance, we analysed a set of 98 F(8) recombinant inbred (RI) lines derived from the cross Camp RemyxMichigan Amber. We also mapped QTLs for adult resistance to yellow rust using the International Triticae Mapping Initiative RI population (114 lines derived from the cross Opata85xsynthetic hexaploid). Two and five QTLs, respectively, were identified from these two populations. This work has highlighted the importance of the centromeric region of chromosome 2B and the telomeric regions of chromosomes 2AL and 7DS in durable yellow rust resistance. The same chromosomal regions are also implicated in resistance to other pathogens.