4种虫生真菌对储粮害虫黄粉虫不同虫态的生防研究

Biocontrol of 4 Entomogenous Fungi on Different Stages of Tenebrio molitor

【目的】通过研究虫生真菌对黄粉虫不同虫态的生防效果,以期为储粮害虫的生物防治提供参考。【方法】在实验室模拟干燥的储粮环境,测定了4种虫生真菌菌株(金龟子绿僵菌MAX-2、玫烟色棒束孢IFK-20、球孢白僵菌BBL-3、蝉棒束孢ICG-1)对黄粉虫3种不同虫态(8龄幼虫、蛹、刚羽化的成虫)的生防效果。【结果】在模拟储粮环境中,BBL-3对3种虫态的毒力都较低,说明该菌株不适宜在干燥条件下发挥作用;MAX-2对幼虫和成虫的毒力都最高,IFK-20其次;孢子悬液处理蛹,ICG-1致死速度最快,其次为MAX-2与IFK-20;ICG-1在模拟储粮环境中对幼虫和成虫无毒力,但用其孢子悬液处理蛹,毒力却达到最高,说明虫生真菌有的对不同虫态的毒力较稳定,而有的可能只在昆虫某些发育阶段或在特定环境中发挥有效作用。对MAX-2侵染黄粉虫不同虫态的特征进行了描述,发现其防治害虫的效果具有持续性,部分被感染的幼虫和蛹可以带菌生存,但生活力下降,有的发育畸形,最终都会死亡。【结论】不同虫生真菌菌株对不同虫态的毒力差异显著,同一菌株对不同虫态的毒力也不同。除ICG-1外其它3株菌在黄粉虫不同发育阶段都具有较好防效,MAX-2对3种虫态的持续防效最好,有望应用于储粮害虫的生物防治。

[ Objective ] The biocontrol effects of different entomogenous fungus on different stages of Tenebrio molitor were tested so as to provide a reference for biological control of stored grain insects. [ Method ] In dry environment with simulated grain storage, the effects of 4 strains （Metarhizium anisopliae MAX-2, lsaria fumosorosea IFK-20, Beauveria bassiana BBL-3, lsaria cicadae ICG-1 ） on 3 stages of T. molitor （ larvae of 8 instars, pupa, newly emerged adults） were tested. [ Result ] In the environment with simulated grain storage, BBL-3 had relatively low virulence to 3 stages of insects, showing that it was not appropriate to effect in desiccation. The virulence of MAX-2 was the highest both to the larvae and the adults, IFK-20 was the second. For the pupae treated by spore suspension, the lethal speed of ICG-1 was the fastest, then MAX-2 and IFK-20. ICG-1 showed no virulence to the larvae and the adults in the environment with simulated grain storage, but its virulence could reach the highest, suggesting that some of the entomogenous fungi could keep stable virulence at different stages of insects, while some might only play an effective role at certain developmental stage of insects or in specific environment. The infective characteristics of MAX-2 against T. molitor at different stages were described, showing that its control efficacy was sustainable. Some of the infected larvae and pupa could survive as carriers, while their viability declined and some turned developmental malformation, eventually leading to death. [ Conclusion]The virulence for strains of different species was significantly different and the virulence for the same strain to different stages of insects was also different. These strains except ICG-1 had good effect at different stages of T. molitor and MAX-2 showed the best sustainable efficacy to 3 stages of T. molitor, indicating hopeful application for biological control of stored grain insects.