Pine wilt disease, caused by Bursaphelenchus xylophilus (pine wood nematode), leads to severe environmental and economic damage. Here, we report the results of experiments on the biological control of pine wilt disease through termination of the insect vector of the nematode and the mechanism of the insecticidal action of Metarhizium anisopliae JEF-279 against Monochamus alternatus (Japanese pine sawyer). A combined treatment with a fungal conidia suspension and a fungal protease-containing culture filtrate caused 75.8% mortality of the insect vector. Additionally, the presence of destruxins was confirmed in the dead Japanese pine sawyer adults, and half of the 10 protein spots in proteomic analysis were identified as an actin related to muscle contraction. Based on proteomic and microscopic analyses, the infection cycle of the Japanese pine sawyer by M. anisopliae JEF-279 was inferred to proceed in the following sequence: (1) host adhesion and germination, (2) epicuticle degradation, (3) growth as blastospore, (4) killing by various fungal toxins (insecticidal metabolites), (5) immune response as defense mechanism, and (6) hyphal extrusion and conidiation. Consequently, the combined fungal conidia suspension and protease-containing culture filtrate treatment may be applied as an insecticidal agent, and flaccid paralysis is likely a major mechanism underlying the insecticidal action of M. anisopliae JEF-279 on host insects.

中文翻译：

---

iso虫对成年日本松木wy甲虫（Monochamus alternatus）的杀虫作用机理

由松材线虫（Bursaphelenchus xylophilus）（松木线虫）引起的松枯病导致严重的环境和经济损失。在这里，我们报告了通过终止线虫的昆虫载体而对松树枯萎病进行生物防治的实验结果，以及对拟南芥JEF-279防治松墨天牛的杀虫作用机理的实验结果（日本松木锯工）。用真菌分生孢子悬浮液和含有真菌蛋白酶的培养滤液的组合处理导致昆虫载体的死亡率为75.8％。另外，在死去的日本松锯木工成虫中证实存在destruxins，蛋白质组学分析中的10个蛋白质斑点中有一半被鉴定为与肌肉收缩有关的肌动蛋白。基于蛋白质组学和微观分析，anisopliae对日本松锯的感染周期推测JEF-279按以下顺序进行：（1）宿主粘附和萌发，（2）表皮降解，（3）芽孢杆菌生长，（4）被各种真菌毒素（杀虫代谢物）杀死，（5）免疫作为防御机制的反应，以及（6）菌丝的挤压和分生。因此，真菌分生孢子悬浮液和含蛋白酶的培养物滤液的组合处理可以用作杀虫剂，而弛缓性麻痹可能是M.Anisopliae JEF-279对寄主昆虫的杀虫作用的主要机理。