不同生长条件下球孢白僵菌菌株的生长状况及对美国白蛾幼虫的致病力研究

摘要

试验所用球孢白僵菌（Beauveria bassiana）是从受侵染的美国白蛾[Hyphantria Cunea（Drury）]蛹体内分离出的菌株,再进行纯化,获得球孢白僵菌纯菌落。研究测定了不同生长条件对球孢白僵菌菌株的营养生长、孢子萌发以及对不同龄期美国白蛾幼虫致病力的影响。结果表明：相对湿度为90%时,菌株的营养生长最好,随着相对湿度的增大,孢子萌发速度、萌发率也增高;相对湿度为100%时孢子萌发率达到最高。经紫外线照射后菌株的营养生长速度缓慢,孢子萌发率降低。相对湿度为90%时被该菌株感染的美国白蛾幼虫的死亡率最高,3龄幼虫的死亡率比6龄幼虫高。%In this experiment,the mycelium of Beauveria bassiana was separated from infected hyphantria cunea pupae before it was purified.The effect of humidity and ultraviolet radiation on the mycelium growth,spores germ ination and the pathogenicity against hyphantria cunea larvae of a Beauveria bassiana strain were tested.The results showed that the optmium relative humidity for mycelium growth and spores germ ination was RH 90%,and at RH 90% hyphantria cunea larvae had highest motality.The germ ination speed and rates of spores increased as the RH increasing,and the 3rd larvae died more quickly than the 6th under 90% RH.The rates of spores decreased for irradiated by ultraviolet radiation.