大豆疫霉病菌致病性分化研究

Races and virulence phenotypes of Phytophthora sojae in Heilongjiang province and Mongolia Region of China

对采自黑龙江省和内蒙古地区的 15株大豆疫霉病菌 (P .sojae)进行了生理小种鉴定 ,只有 4株表现稳定的抗感反应 ,其中 3株为 38号小种 ,能克服所有 8个鉴别寄主所携带的抗病基因 ,表现出较强的致病性 ;9个菌株(占 6 0 % )能克服 4个以上Rps基因 ,包括多抗基因Rps1k、Rps1c和Rps1a ,说明黑龙江省P .sojae群体毒性构成复杂 ,且存在一定比例强毒性菌株 ,对大豆生产构成潜在威胁。长期保存的P .sojae菌株致病性发生变化 。

Among 15 P.sojae isolates, which collected from Heilongjiang province and Mongolia Region of China, three were identified as race 38, consisting of 20% of the isolates. Undescribed virulence phenotypes constituted 80% of the isolates. A number of these new races were virulent on Harlon, the source of Rps 1a, Williams 79, the source of Rps 1c, and Williams 82, the source of Rps 1k.