Abstract：
Biological control is widely used for integrated pest management. However, there are many abiotic factors that can affect the biocontrol efficiency. In this study, we investigated the susceptibility of Hyphantria cunea larvae to Beauveria bassiana under Cd stress, and the corresponding mechanism was analyzed around innate immunity and energy metabolism. The results showed that mortality of H. cunea larvae treated with Cd and B. bassiana was significantly higher than those treated with B. bassiana alone, and the combined lethal effect exhibited a synergistic effect. Compared with the single fungal treatment group, the total hemocyte count in the combined Cd and fungal treatment group decreased significantly, accompanied by a decrease in phagocytosis, encapsulation, and melanization activity. The expression levels of three phagocytosis-related genes, one encapsulation-promoting gene, and one melanization-regulating gene were significantly lower in the combined treatment group than those in the single fungal treatment group. Furthermore, pathogen recognition ability, signal transduction level, and immune effector expression level were weaker in the combined treatment group than those in the single fungal treatment group. The expression levels of 14 key metabolites and 7 key regulatory genes in glycolysis and tricarboxylic acid cycle pathways were significantly lower in the combined treatment group than those in the single fungal treatment group. Taken together, the weakness of innate immunity and energy metabolism in response to pathogen infection resulted in an increased susceptibility of H. cunea larvae to B. bassiana under Cd pre-exposure. Microbial insecticide is a preferred strategy for pest control in heavy metal-polluted areas. AVAILABILITY OF DATA AND MATERIAL: All the data that support the findings of this study are available in the manuscript.
摘要：
生物防治广泛用于病虫害综合治理。然而,有许多非生物因素会影响生物防治效率。在这项研究中,我们调查了美国白蛾幼虫在镉胁迫下对白僵菌的敏感性，并围绕天然免疫和能量代谢分析了相应的机制。结果表明，用Cd和球孢芽孢杆菌处理的楔子幼虫的死亡率明显高于单用球孢芽孢杆菌处理的幼虫，联合致死效应表现出协同作用。与单一真菌治疗组相比，Cd和真菌联合治疗组的总血细胞计数显着下降，伴随着吞噬作用的减少，封装，和黑化活动。三个吞噬相关基因的表达水平,一个促进封装的基因，联合治疗组的黑化调节基因明显低于单一真菌治疗组。此外，病原体识别能力，信号转导水平，联合治疗组的免疫效应蛋白表达水平弱于单一真菌治疗组。联合治疗组糖酵解和三羧酸循环途径中14个关键代谢产物和7个关键调控基因的表达水平明显低于单一真菌治疗组。一起来看,对病原体感染的先天免疫和能量代谢的减弱导致了在Cd暴露前的条件下，楔子幼虫对B.basiana的易感性增加。微生物杀虫剂是重金属污染地区病虫害防治的首选策略。数据和材料的可用性：支持本研究结果的所有数据均可在手稿中获得。
