基于形态和分子标记的桃蛀螟复合体物种分化研究

Most agricultural pests are characterized by wide distribution, various hosts, and large frequency, and occur different levels of genetic differentiation during long evolutionary history on the effect of geographical isolation, host isolation and different environment conditions of stress. The yellow peach moth Conogethes punctiferalis (Guenée) is an important agricultural pest and feeds on more than 40 host plants, including various fruit trees, crops, and even coniferous trees. Previous studies indicate that C. punctiferalis has exhibited remarkable differences in morphology, physiology and biochemistry among different host plants or regions and been a species complex undergoing speciation. However the degree of species differentiation is not clear yet. This project aims to verify the status of relative species and study the genetic differentiation of C. punctiferalis based on the microsatellite and mitochondrial DNA markers in combination with morphology and biology, expecting to investigate the genetic diversity and structure, analyze the gene flow and phylogenetic relationship, trace the history of species dispersal, and explore the possible causing factors. The completion of the project can clarify the species differentiation, provide guidance and theoretical basis for developing pest management strategies and domestic quarantine strategies in the potential geographic distributions of C. punctiferalis complex, and also serve as a reference for the research on related issues of agricultural pests.

农业害虫多数具有分布广、寄主多、发生量大等特点。受地理隔离、寄主分化和不同环境条件的胁迫影响，很多多食性害虫在长期进化过程中会出现不同程度的遗传分化。桃蛀螟Conogethes punctiferalis (Guenée)是重要的多食性害虫，为害多种果树、作物甚至针叶树，寄主植物多达40余种。前期研究表明，在不同寄主上，不同地理区，桃蛀螟的形态、遗传、和生理生化等方面均已出现明显差异，成为一个正在经历物种分化的复合体，但它目前究竟分化到什么程度尚缺乏深入研究。本项目采用微卫星和线粒体基因分子标记技术，结合形态学和生物学，综合研究我国桃蛀螟的遗传多样性、遗传结构、种群间的基因流动及谱系生物地理学亲缘关系，追溯其扩散历史并探讨其分化成因。本项目的完成，可明确我国桃蛀螟物种分化程度，对制定桃蛀螟综合防治策略具有重要指导意义，也可为农业害虫相关问题的研究提供借鉴。