2011—2014年河南省小麦白粉菌群体毒性结构分析

Virulence structure of the wheat powdery mildew population in Henan province in China during 2011-2014

小麦白粉病是小麦生产上的重要病害，在我国各主要麦区均有发生。上世纪70年代后期以来．随着小麦矮秆品种的推广、水肥条件的改善和小麦白粉病单一抗源的利用，再加上小麦白粉菌生理小种高度变异等因素的影响，导致小麦白粉病的发病面积和危害程度维持在一个较高的水平。

In order to investigate the population structure of wheat powdery mildew in Henan province, thirtynine differential hosts were used to analyze the virulence of 298 wheat powdery mildew isolates collected from 10 different counties/cities of Henan during 2011-2014. The results showed that the virulence frequencies to the resistance genes Pm3a, Pm3b, Pm3c, Pm3d, Pm3e 、 Pm3f , Pm4a （ Khapli/Scc ） 、 Pm4b、 Pm6、 Pm7, Pm8, Pm13 Pm17,Pm19、Pm4＋8 and Pm5＋6 were over 90.00%, indicating that these genes have lost the resistance and can not be separately used as resistant sources in wheat powdery mildew resistance breeding. The virulence frequencies to the resistance genes Pm5b、Pm16,Pm21 ,Pm35、Pm2＋Ta and Pm1＋2＋9 were lower than 15.00%, indicating that these genes have a better resistance and can still be used in the breeding for the disease resistance. Viru- lence isolates to genes Pm16 and Pm21 only presented in an individual area. The result will provide information of the distribution of resistance genes and cultivars, and wheat powdery mildew resistance breeding.