C-型草地贪夜蛾幼虫肠道细菌多样性及寄主适应机理研究

C-型草地贪夜蛾是2018年12月入侵我国的一种广食性害虫，对玉米表现出极强适应性。昆虫肠道细菌多样性及对单食和寡食性害虫寄主适应调控作用与机理已经明确，但广食性却又表现出明显适应寄主形成寄主生物型的昆虫其肠道细菌多样性及寄主适应机理研究还很少见，新发生的草地贪夜蛾其肠道细菌多样性及适应玉米的机理尚不清楚。本项目拟以草地贪夜蛾入侵我国的第一站—云南普洱为基地，以田间不同季节草地贪夜蛾自然种群幼虫，及室内分别用玉米、水稻、玉米与水稻混合饲养的实验种群幼虫为材料，采用培养组学和16SrDNA扩增子测序研究草地贪夜蛾不同寄主种群幼虫肠道细菌多样性；通过高深度宏基因组测序与宏转录组技术研究肠道细菌对纤维素及玉米抗虫物质丁布和水稻抗虫物质稻酮的降解作用，探明入侵我国的C-型草地贪夜蛾幼虫肠道细菌多样性及玉米适应性机理。研究结果将为肠道细菌与昆虫互作及害虫寄主生物型形成机制研究提供新思路。

The fall armyworm, Spodoptera frugiperda（J. E. Smith）, is a very serious polyphagou pest, it invaded into China on December in 2018, it showed a significant preference and strong fitness to corn. The bacterial diversity and the adjust function on the host fitness and its mechanism in some monophagous and oligophagous insects are clear, but few reports can be found for those polyphagou insects. The bacterial diversity and function on the host fitness mechanism are unknown. This study will be made on the dynamics of gut microbial diversity of S.frugiperda in Jiancheng county of Puer, and the predominant species of gut bacterial from the gut of the larvae C- strain S.frugiperda feeding on corn leaf, rice leaf and corn-rice leaf combined food using the 16S rDNA sequencing and culture methods. The degradation function of the gut bacterial for the cellulose, DIMBOA and flavonoids will be evaluated using the high depth metagenomics and metatranscriptomics techniques, so as to clarify the host fitness mechanisms of S. frugiperda on corn. The results of this study will provide a new method for the study on the relation between the gut bacteria and insect, as well as the mechanism of host fitness .