Abstract:In the previous study, 3 virulence mutants of wheat stripe rust pathogen, Puccinia striiformis, with GUS insertion were obtained. In this study, expression of GUS gene was analyzed by histochemical staining with X-Gluc, and confirmed by specific PCR and Southern blot. The results indicated that the alien gene GUS was integrated and could inherit stably in the stripe rust genome. The pathogenicity of the 3 mutants on 17 wheat stripe rust differentials and 37 extension cultivars was different from that of the wild isolate. The inserted alien fragment resulted in the pathogenic variation of the mutants. The insertion sites of foreign gene were relevant to the virulent gene of Puccinia striiformis. This study provides a basis for the cloning of the avirulent genes.