摘要： 1985-1987年在温室条件下，采自河南省不同地区的小麦白粉菌群体，对本省当前推广的小麦品种的毒为频率均大于76.55%；区试品种（系）中的花培28和周80-48的毒力频率分别为6.25%和8.75%，抗性较好。利用联合致病性分析，确定了花培28与百泉792、郑州7920和周80-48是今后适于推广的品种组合。研究初步证明豫东、西、南部的小麦白粉菌群体结构基本相似。毒性基因V₁、V_3b、V_3c、V₅和V₉的平均频率较高（66.67-82.76%），V₂、V_2x、V₄、V_4（+）和V₈的平均频率低（7.06-13.38%）。并讨论了小麦品种的合理布局和抗源利用等问题。

关键词: 小麦白粉菌, 毒力频率, 联合致病性, 毒性基因

Abstract: During 1985-1987,forty-four wheat materials belonging to commercial culti-vars,wheat selections in regional test and s’ources of resistance have been inoculated respectively in greenhouse with 81 isolates of Erysiphe graminis f.sp.tritici coll-ected from different regions in Henan Province.The results showed that the virulence frequency of these isolates on commercial cultivars was higher than 76.55%,the vir-ulence frequency of these isolates on Huapei 28 and Zhou 80-48 belonging to regional test was 6.25% and 8.75% respectively.Pathogenicity association was also analysed.The results of interaction between varieties carrying resistant gene and mildew popula-tion showed similar structure of mildew population in three regiones in Henan Province.Virulent genes V1,V3b,V3c,V5 and V9 have high frequencies(66.67-82.76%),while genes V2,V2 x,V4 and V8 have lowor frequencies(7.06-13.38%).Some questions such as the use of resistent sources in disease-resistance breeding were disscussed.

Key words: Wheat powdery mildew, Viruknee frequency, Pathogenicity association, Virulent gene