Diagnostic detection and genetic analysis of wheat stripe rust resistant gene YrCN19

DNA samples of 19 wheat cultivars or lines were screened with the primer pair Xgwm410, a diagnostic marker of wheat stripe rust resistant gene YrCN19. The results showed that the wheat cultivars or lines CN19, XK5, AIM5 and AIM6 produced the amplicon Xgwm410/391, which co-segregated with the resistance of YrCN19, but other cultivars or lines did not produced it. Pedigree analysis and resistance test showed that CN19, XK5, AIM5 and AIM6 carried wheat stripe rust gene YrCN19. Genetic analysis proved that the resistance to wheat stripe rust of CN19, XK5, and AIM5 inherited in single dominant gene genetic law (3 resistant: 1 susceptible). The results also proved that the resistance descent in the cross combination Yanfu188/AIM6 complied with the single dominant gene genetic law (3 resistant: 1 susceptible), while the resistance inheritance in other cross combinations (CN18/AIM6, Lu955159/AIM6 and Shu3110/ AIM6) complied with two gene complementary genetic law (9 resistant: 7 susceptible). The results suggested that the resistance expression and separation of YrCN19 was distinct in the various genetic backgrounds or cross combinations. This study would expedite the exploitation and utilization of YrCN19 in wheat resistant breeding.