许多昆虫为适应不同的环境而产生多型现象。由于目前对不同生境下昆虫形态变化规律，特别是其分子生态适应机制尚未明确。本项目在我们前期研究的基础上，选择具有典型的代表性的生境，以日本蚱Tetrix japonica为研究对象，进一步对不同生境下该蚱的不同龄期若虫和成虫的外部形态、消化系统、排泄系统、生殖系统进行形态特征比较研究，揭示其形态变化规律；同时结合比较转录组学的分析，识别差异表达基因及其功能，明确形态变化背后的分子机制。最后将形态、环境和分子三要素相结合，分析日本蚱在不同生境下的种群遗传分化成因及其分子生态适应机制。本项目完成将对昆虫响应不同环境下的表型可塑性和微进化方面具有一定的理论意义，对维护生态平衡以保护环境具有实践意义。

In many species, individuals that are genetically similar or even identical can display different morphs of phenotypic plasticity called polyphenism, in which two or more distinct morphs can develop from the same genotype in response to specific environments. So far, it’s unclear to the rule of insects’ morphology changes, especially in their molecular ecological adaptability in different environment. We will select Tetrix japonica as the research objects and they are widely distributed in some typical representative environment on the basis of our previous work. Then, we will further study the different instar nymph and adults’ external morphology, digestive system, excretory system and reproductive system in different environment, and to reveal the morphological changes in insects. Meanwhile, we will carry out comparative transcriptomics analysis of the different instar nymph and adults, to identify the differentially expressed genes and their functions, and to reveal the molecular mechanisms of the morphological changes. Finally, we will combine the three elements including the morphology, environment and molecular to explore the cause of genetic differentiation of population and their molecular ecological adaptability in different environment. This project will have a theoretical significance for the phenotypic plasticity and microevolution of insects in response to different environment. It also has a practical significance to maintain ecological balance to protect the environments.