蒙城大豆疫霉菌的鉴定及其生理小种

IDENTIFICATION AND RACE OF Phytophthora sojae ISOLATES COLLECTED IN MENGCHENG, ANHUI PROVINCE

在安徽省蒙城县对大豆疫霉根腐病的发生情况进行调查。应用选择性培养基对类似大豆疫霉根腐病症状的病株进行病原菌分离 ,在春大豆蒙城早熟青豆病株上分离到 2株疫霉菌 PMC1、PMC2和一些 Fusarium spp.,在夏大豆上分离到的主要病原菌为 Pythium spp.和 Fusarium spp.,未分离到疫霉菌。根据疫霉菌分离物 PMC1和 PMC2形态和生理学特征以及对大豆的专化致病性 ,2个分离物被鉴定为大豆疫霉菌 (Phytophthora sojae Kaufmann & Gerdemann)。应用国际通用鉴别寄主进行生理小种鉴定 ,PMC1和 PMC2的毒力公式分别为 1b,1d,3a,3c,5 ,7和 1b,1d,4 ,5 ,为新的小种类型 ,定名为中国 6号小种、中国 7号小种 (CNR- 6和 CNR- 7)。这是首次报道大豆疫霉菌在我国淮北地区存在。

Two Phytophthora isolates, PMC1 and PMC2, were isolated from diseased plants of spring soybean cv. Mengcheng Zao Shu Qing Dou in Mengcheng, Anhui. Based on their morphology, physiology and pathogenicity to soybean, PMC1 and PMC2 were identified as Phytophthora sojae Kaufmann & Gerdemann. By hypocotyl inoculation on the differential soybean cultivars, PMC1 and PMC2 were identified as two new races and proposed as Chinese race 6(CNR 6, virulence formula = 1b,1d,3a,3c,5,7) and Chinese race 7(CNR 7, virulence formula = 1b,1d,4,5). No isolates of Phytophthora were isolated from diseased plants of summer soybean cultivars in Mengcheng. It is the first report that Phytophthora sojae exists in Huaibei region, China.