本研究对分离自二点委夜蛾Athetis lepigone（Moschler）越冬幼虫僵虫上分离的43株球孢白僵菌菌株进行生物测定,筛选到致病力较强的4株菌株,并对这4株菌株的菌落形态、菌株生长速度、产孢量和萌发率等生物学性状进行了测定。同时以二点委夜蛾2龄幼虫为供试虫源,测定了这4株白僵菌菌株对二点委夜蛾的致病力,从中筛选出具有生长速度快、萌发率高、产孢量大等培养性状优及毒力较强的球孢白僵菌Ed-41菌株。该菌株在浓度为1×107孢子.mL-1悬浮液喷雾接种处理后,在26℃条件下,第8 d供试幼虫的死亡率达85%,显示出对靶标害虫的具有较好的毒力,在二点委夜蛾害虫生物防治中将有潜在的的应用价值。%Biological characteristics of Beauveria bassiana strains isolated from dead overwintering Athetis lepigone （Moschler） larvae were determined and strains of high virulence to A. lepigone were screened in laboratory. Four strains of relatively high virulence were isolated from 43 strains by bioassays. Morphology feature, growth rate, sporulation, germination rates, and virulence against the 2nd instar larvae ofA .lepigone were compared between the 4 strains. One high virulent isolate, Ed-41, was obtained; the Ed-41 strain showed the fastest colony growth, highest germination rate and sporulation, and also highest toxicity to 2nd instar larvae of A. lepigone. The strain caused 89.47% of 2nd larvae of A. lepigone dead at 26℃ 8 d after spray inoculation at a concentration of 1×10^7 spores.mL-1. The results show that the strain Ed-41 is highly toxic to A. lepigone and has the potential for use in biological control of the insect pest.
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