西昌地区茄子白粉病病原菌的初步鉴定及分生孢子的萌发特性

Preliminary Identification of Pathogen Causing Eggplant Powdery Mildew in Xichang District and Its Conidia Germination Characteristics

对四川省西昌地区茄子白粉病病原菌进行了初步鉴定,并对其分生孢子萌发特性进行了研究。结果表明:西昌地区茄子白粉病病原菌的分生孢子单生,初生分生孢子顶端略尖,大小为(65.44～84.98)μm×(17.31～22.09)μm,次生分生孢子两端钝圆,大小为(69.92～83.32)μm×(15.82～21.53)μm;分生孢子梗不分支,2～4个细胞,长102.59～179.50μm,未发现有性世代,初步鉴定为旱金莲内丝白粉菌〔Oidiopsistropaeoli(Berger.)〕。分生孢子萌发特性研究表明,其最佳萌发温度为25℃,致死温度54℃;相对湿度90%以上分生孢子可以萌发,保湿条件下萌发率最高;光照对孢子萌发有一定抑制作用。

The pathogen of eggplant powdery mildew in Xichang district,Sichuan province was identified and the characteristics of conidial germination was studied.The results indicated that the conidial of pathogen causing eggplant powdery mildew in Xichang district was single birth.The top of the primary conidia was cuspate,(65.44-84.98)μm×(17.31-22.09)μm by size.The secondary one was cylindrical,(69.92-83.32)μm×(15.82-21.53)μm by size.Conidiophores were unbranched,with 2-4 cells and 102.59-179.50 μm in length.Chasmothecia was not observed.The pathogen was initially identified as Oidiopsis tropaeoli(Berger.).Conidia germination characteristics study indicated that the optimum temperature for germination was 25 ℃,and the lethal temperature for conidia was 54 ℃.Conidia could germinate while the relative humidity was above 90%,but under 100% moisture condition the germination rate was the highest.Light had inhibitory effect on conidia germination.