云南省稻瘟病菌生理小种演变及稻种资源垂直抗性基因的利用

Race evolution of Magnaporthe grisea and evaluation of rice vertical re sistant genes in Yunnan

1993～ 1 997年从云南省 32个县 (市 )采集、分离到 80 0余个稻瘟病菌分生孢子单孢菌株。从中选出来自 2 1个县 (市 )的 1 5 5个菌株 ,用日本鉴别品种鉴定 ,结果可分为 78个生理小种 ,出现频率最高的为 1 36 4(出现频率 6 5 % ) ,较高的有 31 7 4(5 2 % )、 0 0 7(5 2 % )、 1 37 4(4 5 % )、 0 0 3(3 2 % )、 0 0 7 5(2 6 % )。稻瘟病菌的致病谱比 1 983～ 1 988年的小种有了明显增强 ,这主要是由于栽培了抗病较强的水稻品种的原因。根据生理小种在各稻作区的组成和分布 。

A total of 155 M grisea single conidia isolates collected from 32 counties in Yunnan rice grown regions were identified by using 9 single gene differential varieties and 2 reference varieties from Japan during 1993～1997 These isolates might be divided into 78 races,in which the predominant races were 136 4(frequency 6 5%),317 4(5 2%),007(5 2%),137 4(4 5%),003(3 2%)and 007 5(2 6%) The results indicated that the distribution and composition of races had much changed compared with the results identified during 1983～1988 Virulent spectrum of isolates was wider than that 10 years ago Meanwhile,the availability of some rice vertical resistant genes were evaluated by analyzing infection frequency of these resistant genes in different rice regions