| Stripe rust is one of the most serious diseases of wheat in the worldwide. Planting resistant cultivars is the most effective, economical and environment-friendly method to control this disease. However, high genetic variation and the ability of the pathogen to evolve into new races with added new virulence always have been the major limiting factor in a successful long-term management of stripe rust when race-specific resistance genes are used. As a result, one cultivar"loses"its resistance in several years. In recent years, CYR32 became into the most popular race of stripe rust. So, for controlling stripe rust, identifying new resistance genes, developing new sources of stripe rust resistance, rational distribution of resistance wheat lines are importance methods. In this study, 239 of varieties/lines from Huang-Huai wheat Region were detected by SSR markers and 320 cultivars and lines from Huang-Huai wheat region were tested to identify their resistances to stripe rust, resistance gene to stripe rust in resistance source HPL60469 was analysed by genetic method.A total of 239 wheat varieties and lines from Huang-Huai wheat regions were detected by SSR markers, Xgwm11 and Xgwm18, which closely linked to Yr26. The result showed that 33 varieties/lines had the Xgwm11 marker for Yr26, 29 wheat varieties/lines (88.77%) resistant to stripe rust; 31 varieties/lines had the Xgwm18 marker for Yr26, 31 wheat varieties/lines(93.55%) resistant to stripe rust; 29 cultivars/lines had the Xgwm11 and Xgwm18 markers for Yr26, 27 wheat varieties/lines (93.10%) resistant to stripe rust. The results of Molecular marker and resistance assessments to stripe rust were very similar. Molecular markers and resistance assessments information confirmed that 31 varieties/lines had gene Yr26 which frequency was 12.97% in the detected cultivars and lines.320 varieties and lines from Huang-Huai wheat region were tested to identify their resistances to stripe rust. The result showed that 70.62% of all the tested varieties and lines were resistance to stripe rust, including the 143 pieces of immunity material to stripe rust, 33 pieces of highly resistant material, 50 pieces of moderate resistant material, 29.38% of all tested varieties and lines were susceptible to stripe rust, including 33 pieces of medium susceptible material, 61 pieces of highly susceptible material.In this study, F2, F3 and BC1 seeds were prepared by crossing Huixianghong, a susceptible variety, as female parent and HPL60469, as male parent. Resistance of HPL60469 and its hybrid progenies were analyzed genetically by artificial inoculation with CYR32. The R/S segregation ratio of F2 progenies conformed to 3:1 corresponding with the heredity rules of one pairs of dominant resistance genes (p=0.80~0.90). F3 progenies in this study were derived from self-pollinated monosomic F2 plants which were resistance to stripe rust. Ratio of resistance and susceptible of F3 progenies conformed to 2:1 corresponding with the heredity rules of one pairs of dominant resistance genes (p=0.30~0.50). Ratio of resistance and susceptible of BC1 progenies conformed to 1:1 corresponding with the heredity rules of one pairs of dominant resistance genes (p=0.30~0.50). Based on the data of resistance phenotypes of F1, F2, BC1 plants and their parents, it was revealed that the resistance of HPL60469 to the race CYR32 was controlled by a single dominant gene.In this paper, F1, F2 seeds were respectively prepared by crossing HPL60469 as female parent and 92R137 and Guinong21 which have resistance gene Yr26 as male parents. Two F1 plants were immune to the race CYR32. Ratio of resistance and susceptible of two F2 progenies to CYR32 conformed to 15:1 corresponding with expect ratio(p=0.95~0.99,p=0.50~0.70). In considering the allelic test of two F1 and two F2 populations as well as pedigree analysis, the resistance gene of PHL60469 to CY32 is a new stripe rust resistance gene.
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