Li Dan-Dan, Li Jin-Yang, Hu Zu-Qing, Liu Tong-Xian, Zhang Shi-Ze
State Key Laboratory of Crop Stress Biology for Arid Areas, College of Plant Protection, Northwest A&F University, Xianyang 712100, China.
Insects. 2022 Aug 24;13(9):762. doi: 10.3390/insects13090762.
The fall armyworm, (Lepidoptera: Noctuidae), is a major invasive pest that seriously threatens world agricultural production and food security. Microorganisms play a crucial role in the growth and development of insects. However, the diversity and dynamics of gut microbes with different developmental stages, environmental habitats, and diets in remain unclear. In this study, we found the changes of the microbiome of across their life stages, and the bacteria were dominated by Firmicutes and Proteobacteria. The community composition of the egg stage was quite different from other developmental stages, which had the highest community diversity and community richness, and was dominated by Proteobacteria. The bacterial community compositions of male and female adults were similar to those of early larvae stage (L1-L2), and operational taxonomic units (OTUs) with abundant content were and Enterobacteriaceae bacteria, including , , , and . The third instar larvae (L3) mainly consist of . The late stage larvae (L4-L6) harbored high proportions of , and . There was no significant difference in gut microbial composition between field populations and laboratory populations in a short period of rearing time. However, after long-term laboratory feeding, the gut microbial diversity of was significantly reduced. and of feeding on maize showed higher relative proportion, while the microbial community of feeding on artificial diet was composed mainly of , with a total of 98% of the gut microbiota. The gene functions such as metabolism, cell growth and death, transport and catabolism, and environmental adaptation were more active in feeding on corn than those feeding on artificial diet. In short, these results indicate that developmental stage, habitat, and diet can alter the gut bacteria of , and suggest a vertical transmission route of bacteria in . A comprehensive understanding of gut microbiome of will help develop novel pest control strategies to manage this pest.
草地贪夜蛾（鳞翅目：夜蛾科）是一种主要的入侵害虫，严重威胁世界农业生产和粮食安全。微生物在昆虫的生长发育中起着至关重要的作用。然而，草地贪夜蛾不同发育阶段、环境栖息地和食物条件下肠道微生物的多样性和动态变化仍不清楚。在本研究中，我们发现了草地贪夜蛾整个生命阶段微生物组的变化，其细菌主要由厚壁菌门和变形菌门主导。卵期的群落组成与其他发育阶段有很大不同，具有最高的群落多样性和群落丰富度，且以变形菌门为主导。雄性和雌性成虫的细菌群落组成与早期幼虫阶段（L1-L2）相似，含量丰富的可操作分类单元（OTU）是肠杆菌科细菌，包括埃希氏菌属、克雷伯氏菌属、肠杆菌属和沙雷氏菌属。三龄幼虫（L3）主要由芽孢杆菌属组成。后期幼虫（L4-L6）含有高比例的芽孢杆菌属、泛菌属和沙雷氏菌属。在短期饲养时间内，田间种群和实验室种群的肠道微生物组成没有显著差异。然而，经过长期实验室饲养后，草地贪夜蛾的肠道微生物多样性显著降低。以玉米为食的草地贪夜蛾中肠杆菌属和克雷伯氏菌属的相对比例较高，而以人工饲料为食的草地贪夜蛾的微生物群落主要由泛菌属组成，占肠道微生物群的98%。与以人工饲料为食的草地贪夜蛾相比，以玉米为食的草地贪夜蛾中代谢、细胞生长和死亡、转运和分解代谢以及环境适应等基因功能更为活跃。简而言之，这些结果表明发育阶段、栖息地和食物条件可以改变草地贪夜蛾的肠道细菌，并提示了草地贪夜蛾中细菌的垂直传播途径。全面了解草地贪夜蛾的肠道微生物组将有助于开发新的害虫控制策略来管理这种害虫。
