Entomopathogenic fungi (EPF) attack a wide range of insects. They are considered environmental friendly alternatives to synthetic insecticides for pest control. In the present study, virulence of a native isolate of the EPF, Beauveria bassiana Vuillemin (Hypocreales: Cordycipitaceae) was evaluated against the least mulberry pyralid, Glyphodes pyloalis Walker (Lepidoptera: Crambidae), through bioassay, pathogenic pathways, and immune responses. The values of 2.6 × 104 conidia/ml and 3.54 days were determined as the median lethal concentration (LC50) and median lethal concentration (LT50) of AM-118 against the 4th instar larvae of G. pyloalis, respectively. The activities of proteases and chitinases in the culture medium containing the larval cuticle were higher than the control medium. Moreover, the total and the differential hemocyte counts of the larvae were significantly changed after injection with AM-118 spores. The highest numbers of total hemocytes and granulocytes were obtained 3 and 6 h post-injection, while the highest numbers of plasmatocytes and nodules were observed 6 h post-injection. The highest activity of phenoloxidase was determined 12 h post-injection by AM-118 spores. The findings imply on virulence of the AM-118 isolate against the larvae of G. pyoalis although immune responses were triggered by the spores.

中文翻译：

---

球孢白僵菌的天然分离株对Glyphodes pyloalis Walker（鳞翅目：Pyralidae）幼虫的死亡率和免疫挑战

致病性真菌（EPF）攻击多种昆虫。它们被认为是控制害虫的合成杀虫剂的环保替代品。在本研究中，通过生物测定，致病途径和免疫反应，评估了EPF天然分离株球孢白僵菌（Hypocreales：Cordycipitaceae）的毒力对桑树吡醛最少的Glyphodes pyloalis Walker（鳞翅目：Crambidae）的毒性。2.6×104分生孢子/ ml和3.54天的值分别确定为AM-118对幽门螺杆菌第4龄幼虫的中位致死浓度（LC50）和中位致死浓度（LT50）。含有幼虫表皮的培养基中的蛋白酶和几丁质酶的活性高于对照培养基。而且，注射AM-118孢子后，幼虫的总血细胞计数和差异血细胞计数发生了显着变化。注射后3和6小时获得了最高数量的总血细胞和粒细胞，而注射后6小时观察到了最高数量的浆细胞和结节。注射后12 h AM-118孢子测定酚氧化酶的最高活性。该发现暗示了AM-118分离物对脓胸念珠菌幼虫的毒性，尽管孢子触发了免疫反应。注射后12 h AM-118孢子测定酚氧化酶的最高活性。该发现暗示了AM-118分离物对脓胸念珠菌幼虫的毒性，尽管孢子触发了免疫反应。注射后12 h AM-118孢子测定酚氧化酶的最高活性。尽管免疫反应是由孢子触发的，但该发现暗示了AM-118分离物对脓胸念珠菌幼虫的毒性。