川西平原油菜菌核病菌群体结构研究

Studies on populational structures of Sclerotinia sclerotiorum on rape in the western Sichuan province

2002年5月在川西平原4个地区:蒲江大兴、邛崃卧龙、双流黄水和邛崃固驿,从油菜病株茎杆上采集菌核,经分离和鉴定,共得到373个菌株进行菌丝生长速率、对多菌灵敏感性、菌丝融合群和遗传多样性的测定和分析,结果表明:川西油菜菌核病菌群体结构呈地域间和田块内的分化。病菌群体由遗传背景不同的8个亚类组成,而8个亚类的分布呈明显的区域性,不同地点同一田块内核盘菌株分属1(邛崃固驿)至4个(邛崃卧龙)亚类。各亚类由属于多个菌丝融合群的菌株组成,不同地点仅个别菌株属同一菌丝融合群。不同菌株间菌丝生长速度呈较大差异,各采样地点菌株平均生长速度差异较大。生长速度较快的284个菌株对多菌灵普遍敏感。

373 isolates of Sclerotitnia sclerotiorum were collected from rape seed at Daxing Township of Pujiang County, Wolong and Guyi Townships of Qionglai County and Huangshui Township of Shuangliu County in western Sichuan province in May, 2002. After the measurement of the mycelium growth rate, assay of the sensitivity to Carbendazim （MBC）, division of mycelial compatible groups （MCGs） and the analysis of genetic diversity by RAPD, it is indicated that the population of S. sclerotinia in western Sichuan Province could be divided into 8 sub-groups, of which the distribution is localized. The population at each locality is composed of 1 - 4 sub-groups which, in turn, are consisted of the isolates belonging to different MCGs. Few isolates from different localities could be mycelium compatible. Significant difference in mycelium growth rates was found between different isolates and localities. However, all tested isolates of fast mycelium growth were sensitive to MBC.