绿僵菌侵染小菜蛾幼虫过程的透射电镜观察

Observation of infection process of Metarhizium anisopliae on Plutella xylostella larvae with transmission electron microscopy

利用透射电镜观察了绿僵菌Metarhizium anisopliae对小菜蛾Plutella xylostella幼虫的侵染过程。结果表明:接种后22h最早观察到绿僵菌穿透到寄主表皮层中,在穿透表皮过程中伴随着机械力和酶的活动。菌体进入寄主血腔后,以菌丝出芽生殖、菌丝分隔及菌丝段分隔3种方式大量增殖,主要形成颗粒状的菌丝段在寄主体腔内扩散,也形成少量的丝状菌丝。

The infection process of two isolates of Metarhizium anisopliae on Plutella xylostella larvae was studied using transmission electron microscopy. The results showed that the penetration of the integument of P. xylosteUa larva by M. anisopliae, which was first observed in 22 h after inoculation, was the combination of mechanical pressure and enzymatic action. The penetrant hyphae produced lots of granule hyphal bodies by budding or septation, which became distributed throughout the body cavity of infected larva. Some filar hyphae were also seen in the hemocoel of infected larva.