湖南省3个主要稻瘟病区菌株的交配型分布及其生理小种测定(英文)

Distribution of Mating Type and Identification of Physiological Race in Magnaporthe grisea Collected from Three Main Diseased Areas of Hunan Province, China

20 0 1年 9月在湖南省 3个稻瘟病的主要发病县采集分离了 5 7个稻瘟病菌株 ,与法国国际农艺研究和发展中心提供的 4个标准菌株于稻谷粉琼脂培养基上对峙培养。结果表明 ,30 %和 12 %的测试菌株分别为交配型 1.1和交配型1 2 ,其余 6 0 %的测试菌株与 4个标准菌株中的任何一个均不能产生子囊果 ,即便是与田间新获得的两性菌株之间的对峙培养也不能产生子囊果。在所获 2 4个能育菌株中只有 5个为两性菌株 ,占 9%。各菌株在中国 7个鉴别品种上的测定共获 5群 2 0个小种 ,其中ZA和ZB为优势群 ,ZB15为优势小种。还就稻瘟病菌有性世代在田间存在与否进行了讨论。

Fifty-seven mono-conidial blast fungi (Magnaporthe grisea) isolated from three main diseased areas of Hunan Province in September 2001 were co-cultivated on rice flour medium with four standard testers provided by International Center for Collaboration in Agronomic Research and Development (CIRAD) in order to determine their mating types. Results showed that 30% and 12% of the tested isolates were determined as Mat1.1 and Mat1.2, respectively, while the remaining 60% were unknown mating types. A total of 24 fertile strains were obtained, only five of them were female/hermaphroditic isolates, being accounted for 9% of the total tested isolates. The cross between isolates of the opposite mating types did not show any production of perithecia even between hermaphroditic isolates. The Chinese race of each isolate was determined after pathogenicity test to the seven Chinese differential cultivars. ZA and ZB were dominant groups and the race ZB15 was predominant among the 20 races obtained. The perfect stage of M. grisea in the field was also discussed.