更新世的气环循环波动导致物种分布区不断收缩和扩张，促进了近缘种间或群体间的基因交流和遗传多样性动态变化，成为形态演化和适应性进化的重要驱动力。而基因流在维持物种遗传多样性和促进环境适应的分子机制尚不清楚。本项目选择横断山地区特有类群血红杜鹃复合体（杜鹃属）为研究对象，在群体水平上，运用简化基因组（RAD-seq）和转录组测序技术开展种群分化和适应性进化机制研究；通过群体遗传学和表达谱分析，确定其种群遗传多态性、遗传结构和基因流水平以及种群历史动态，同时鉴别重要的适应性基因，澄清基因流、自然选择和表型分化在种系分化和适应性进化过程中的作用和相互关系，以期揭示基因流在维持物种遗传多样性和促进环境适应性进化的分子机制。该项目的实施可为杜鹃属的种系分化的适应机制提供新证据，也可为该属植物资源开发利用提供理论基础。

The Pleistocene climatic oscillations would result in repeated episodes of contraction and expansion of geographic ranges of plant species, which promotes gene flow among closely related species or populations of the species associated with genetic diversity dynamic changes. It is likely the important mechanism of morphological and adaptive evolution. However, the precise mechanism of gene flow for persistence of genetic diversity and improvement of environmental adaptation is largely unkown. In this project, we will sample populations of Rhododendron sanguineum complex endemic to Hengduan Mountains to investigate levels of population structure, genetic diversity and gene flow as well as dynamics of population demography, and identify the important adaptive genes using technologies of SNPs assayed by restriction site associated DNA (RAD) sequencing and transcriptome sequencing employing next-generation sequencing (NGS) technologies. We aim to clarify the roles and correlations of gene flow, natural selection and phenotypic differentiation involved in processes of speciation and adaptive evolution of Rhododendron sanguineum complex, and explore the molecular mechanism of gene flow for persistence of genetic diversity and improvement of environmental adaptation. The study will provide new evidences of adaptive mechanism for species diversification, and also be the basis for scientifically sound proposals for the resource development and utilization of Rhododendron.