小麦白粉病菌群体生理小种和毒性基因结构分析与评价

Survey and Evaluation on Race and Virulence Genes of Wheat Powdery Mildew Population

以１９９０～１９９３年从河南省不同地区采集的３６４个小麦白粉病菌菌株标样为例，应用传统的生理小种鉴定方法和根据与已知抗白粉基因的互作推测毒性基因频率的方法，研究了河南省小麦白粉病菌群体生理小种和毒性基因结构。结果发现白粉病菌群体中生理小种组成及其频率有较大变化，亚号、１０号、１１号和１５号小种的频率均呈下降趋势，而３１号小种的频率呈大幅度上升，至１９９３年已达２０．７５％，跃居各小种之首；对１号、１１号、１５号和３１号小种的毒性基因谱分析发现，不同小种群的小种间至少存在一个以上毒性基因的差异，同小种群的不同小种间则在毒性基因谱上没有显著差异；另外，同一小种不同菌株间的毒性基因谱仍不完全相同，说明小种致病异质性是普遍存在的。毒性基因结构分析表明，Ｖ２、Ｖ２＋６和Ｖ８等毒性基因的频率有较大变化。文中还讨论了两种方法的优缺点和今后工作中如何改进等问题。

During 1990- 1993 a total of 364 isolates of Erysiphe gramings f. sp. indict, collected from different areas in Henan Province, were identified for race with 9 differential hosts and analysed also for virulence genes. In race surveys, 17 races that belonged to 5 race groups were found. The composition of races and their frequencies in mildew population changed quite greatly,the frequencies of race 1, 10, 11 and 15 had a decrease tendency, but the frequency of race 31increased by a wide range, reached 20. 75% in 1993. Virulence spectra of main race were also analysed. The results of virulence gene survey showed that the frequencies of V2,V2+ 6 and V8changed widely. The merits and defects of two testing methods,and the improvement opinions were disscussed also in this paper.