Genetic basis of host sifts in phytophagous insects

利用本项目建立的微卫星标记，对两种同域瓢虫（Henosepilachna niponica和H. yasutomii）的遗传分化程度进行了评估，这两种瓢虫被认为是单独通过寄主偏好而相互隔离的。分析结果表明，种内和种间的遗传变异都很低。这些结果表明，两个物种的物种形成可能是在很短的时间内发生的，除了一些与宿主偏好相关的基因外，它们之间几乎没有遗传差异。

Extent of genetic differentiation between two sympatric ladybird beetles, Henosepilachna niponica and H. yasutomii, which are thought to be reproductively isolated from each other by their host preferences alone, was assessed using microsatellite markers established in this project. The analyzed data revealed that the genetic variation both within and between species were very low. These results suggest that the speciation of two species would have occurred so recently with short time that there is little genetic differentiation between them, except for a number of genes associated with their host preferences.