甜叶菊斑枯病病原菌的生物学特性

The biological characteristics of the pathogenic agent of steviae leaf spot disease

甜叶菊斑枯病病原菌经鉴定为Septoria steviae Ishiba Yokoyama et Tani.,病菌分离菌株生长慢,在8种不同培养基上生长速度、产生分生孢子器和分生孢子的能力相差很大.光照对菌体产孢影响显著,但对菌丝生长没有影响.降低马铃薯葡萄糖琼脂培养基中葡萄糖的含量,菌体生长慢,但可提高单位面积菌体产孢量.微量元素硼在一定范围内有促进产孢的作用.菌体在pH值3～10范围内均可生长,生长最适pH值是5.0～6.0.

Taxonomy identification suggests that the pathogenic agent of steviae leaf spot disease in Heilongjian province is Septoria steviae Ishiba Yokoyama et. Tani. It grew slowly. Its growth ratio and the yield of pycnidium and conidia differed greatly under 8 different culture media. The yield of conidia was affected significantly by illumination, but not the growth ratio of mycelium was. Reducing the glucose content of the PDA culture medium, its mycelium grew more slowly, but the yield of conidia in unit area could be promoted. Boron, as a microelement, could promote the yield of conidia in certain density. This fungus could live in pH 3-10 condition. But the optimal growth condition is pH 5.0-6.0.