选用农家品种白大头与感病品种铭贤169和辉县红组合亲本及F_1、F_2代材料,在成株期自然诱发条件下进行白粉病抗性评价和遗传分析。结果表明,农家品种白大头在田间表现中抗白粉病,田间病级3~4级;亲本铭贤169和辉县红表现中感和高感,田间病级分别为5~6级和7~8级。两组合F_1代植株均表现抗病,田间病级2~4级。301株白大头/辉县红组合F_2代植株中,抗感分离比为214R∶87S,符合3R∶1S的理论比值;286株白大头/铭贤169组合F_2代植株中,抗感分离比为201R∶85S,亦符合3R∶1S的理论比值。表明农家品种白大头成株期对白粉病的抗性由1对显性抗性基因控制。
The wheat landrace cultivar Baidatou is an important germplasm in Gansu province, China. It is used as female parent and hybridized with the susceptible cuhivars Huixianhong and Mingxian 169 at Gangu testing station, Institute of Plant Protection, Gansu Academy of Agricultural Sciences (IPP, GAAS), to study the resistant inheritance of powdery mildew in adult plant stage. The P1, P2, F1 and F2 populations of the crosses are deduced with natural isolates of Blumeria graminis f.sp. tritici. The result shows that the female parent Baidatou is middle resistance, and its scale is 3-4 in field. The male parents Mingxian 169 and Huixianhong are middle and high susceptible, and their scales are 5-6 and 7-8 in field. F1 populations are resistance, and their scales are 2-4 of two crosses, and the F2 populations segregation ratio for the cross of Baidatou/Huixianhong are 214R : 87S, the segregation ratio for the cross of Baidatou/Mingxian 169 are 201R:85S, respectively, which accorded with the expected value for 3R : 1S in Chi-square(χ2) testing for probability of goodness fit. The result indicates that the resistance of wheat landrace variety Baidatou is controlled by one dominant gene to natural isolates of Blumeria graminis f.sp. tritici in adult plant stage.