【摘要】 用采自贵州省的39个小麦白粉病菌株分别对9个鉴别品种和20个已知抗性基因的品种进行毒性频率测定，并于1995年-1996年将这些品种（系）种在3个点上进行异地鉴定，结果表明。抗白粉病基因pm1、pm3b、pm4a、pm4b、pm5、pm5和pm1+2+9、pm4＋8在贵州已无效或失效；pm12、pm17、pm18、pm19、pm21、pm2+6、pm2+M1d、pm2＋6＋1、pm2+4、pm2十4＋6、pm2＋4b+8在贵州是有效的。pm2、pm6、pm7、pm11和pm2x＋4在室内测定毒性频率较高，但在田间成株期严重率较低。小白冬（XBD）在室内外测定均表现很好的抗性．其抗谱与已知基因不同。更多还原

【Abstract】 Using 39 strains of Erysiphe graminis f. sp. tritici in Guizhou province, the virulence frequency was tested for 9 different cultivars and 20 cultivars of known genes, these cultivars were tested at four disease nursery from 1995 to 1997. The results of virulence frequency and field investigation showed that resistance genes pm1, prn3b, pm4a、pm4b、 pm5、 pm8、 pm1 + 2+ 9、 pm4+ 8 was ineffective against wheat powder mildew in Guizhou, pm12、 pm17、pm18, pm19、 pm21、pm2+ 6、 pm2+ 6+1、 pm2+M1d、 pm2+4, pm2+4+6 and pm2+4b+8 were effective. The stains of the pathogen have higher frequency of virulence to pm2、 pm6、 pm7、 pm11 and pm2x+4, but these genes have lower serious degree of disease in the field. Xiao Baiong XBD) has well resistance to wheat powder mildew in the indoor experiments and the field tests. Its resistance tables differ from known resistance genes.更多还原