Abstract:

The aim was to determine the inheritance of resistance in ‘Xinong 291’. In this study, the level of resistance to wheat stripe rust in ‘Xinong 291’ was identified using the predominant races of Chinese Yellow Race (CYR) in the greenhouse and the field. Simultaneously, two susceptible cultivars, ‘Mingxian 169’ and Avocet Susceptible (AvS), were used to cross with the resistant cultivar ‘Xinong 291’ for constructing F1 and F2 genetic populations. Genetic analysis was performed with CYR32 at the adult stage in the greenhouse, and mixed races consisting of CYR32 and CYR33 at a ratio of 1:1 at the adult stage in the field, respectively. The results showed that, in the greenhouse, ‘Xinong 291’ was susceptible to the CYR races of CYR32 and CYR33 at the seedling stage, and highly resistant to the CYR races of CYR32, CYR33, Su11-4, and Su11-7 at the adult stage, respectively. In the field, high resistance to wheat stripe rust in ‘Xinong 291’ was demonstrated by inoculating the mixed races consisting of the predominant CYR races in Yangling, Shaanxi Province, and by natural infection in Tianshui, Gansu Province, respectively. The chi-squre test confirmed that the frequencies of resistance versus susceptible individuals were in accordance with the 3R:1S ratio in the F2 populations of ‘Xinong 291’בMingxian 169’ and ‘Xinong 291’×AvS. These results indicated that ‘Xinong 291’ was of non-race specific and broad spectrum of the adult-plant resistance, and that the resistance of ‘Xinong 291’ to wheat stripe rust is controlled by a single dominant gene.