玉米灰斑病菌生物学特性研究

 玉米灰斑病菌(Cercospora zeae-maydis Tehon and Doniels)适合分离的培养基有花生叶斑病尾孢菌培养基、PDA、V8汁、V8汁+蔗糖20 g和Richard培养基。适宜菌丝生长的pH 4~12,最适宜的pH 6~8,适宜温度为20~25℃。病菌对葡萄糖、麦芽糖、乳糖和对酵母膏、硝酸钾、牛肉膏的利用好于其它碳源或氮源。分生孢子萌发的温度为20~30℃,pH范围广,RH ≥ 81%以上分生孢子萌发,随湿度增加萌发率增高。营养对孢子萌发无影响。

Biological characteristics of Cercospora zeae-maydis

In recent years gray leaf spot of corn caused by Cercospora zeae-maydis Tehon and Doniels became more prevalent in the maize-growing area of northern China. The biological characteristics of pathogen have been investigated. One of optimum media for Cercospora zeae-maydis growth is peanut leaf disk medium, inferior PDA, V8 juice agar, V8 juice plus sugar and Richard's medium. Among the tested carbon and nitrogen resources, glucose, maltose, lactose and yeast extract, KNO₃ and beef extract are useful types, nutrition has no selective effect on conidial germination. For growth of the pathogen, the favorable pH is 4-12 with the optimum pH 6-8, the favorable temperature is between 20-25℃. The suitable temperature for conidial germination is between 20-30℃. The conidia germination has no strict pH requirement that conidia can germinate at RH 81%-98%, or have 100%germination rate in water.