中国主要稻区稻瘟病菌交配型分布及其育性能力的差异

 用4 个稻瘟病菌的标准交配型菌株,对1998～2003 年中国13个省(区)、市,670个稻瘟病菌单孢分离菌株的可育性和交配型进行了测定。结果表明,中国稻瘟病菌广泛存在MAT1-1、MAT1-2两种交配型菌株。可育菌株占测试菌株的40.3%,MAT1-1和MAT1-2菌株分别为21.9%、18.4%。不同稻区稻瘟病菌有性世代的形成能力有很大差异。用PCR技术对中国稻瘟病菌交配型进行快速分子测定,发现MAT1-1和MAT1-2菌株分别占62.5%和37.5%,绝大多数稻区同时存在两种交配型菌株。结果提示,尽管

Mating Type Distribution and Fertility Status of Magnaporthe grisea Populations in Main Regions of China

Six hundred and seventy isolates of Magnaporthe grisea collected from 13 provinces in China from 1998 to 2003 were tested for their mating type and fertility with four standard tested isolates. Results showed that two mating types, MAT1-1 and MAT1-2, exist in China. The percentage of fertile isolates was 40.3% on average, amongst the fertile isolates, 21.9% forMAT1-1, and 18.4% for MAT1-2. The rate of perfect stage formation was very different among the tested isolates. Since both mating type genes had already been cloned, a PCR assay was carried out to determine the mating type of all tested M. grisea isolates, it wasfound that MAT1-1 was 62.5% and MAT1-2 was 37.5% among the 670 isolates. In most of the tested regions, two mating types existed together. It was suggested that though the sexual stage rarely occurred in natural condition, the sexual recombination might still be a potential mechanism for the genetic diversity of Magnaporthe grisea.