物种的准确界定和可靠的系统发育关系是研究生物起源进化和物种形成的基础，也是开展生物多样性保护和利用的关键。而对辐射演化的类群来说，其物种界定和系统发育关系重建是系统学家面临的难题之一。杜鹃属物种多样性高，中国西南为其分布中心，而其分类学和系统学尚存在较多问题。本项目以杜鹃属糙叶杜鹃亚组为例，在居群取样的基础上对该类群全部物种进行形态性状测量和统计分析，基于叶绿体全基因组序列和简化核基因组数据构建系统发育关系，结合地理分布信息与生态学数据，澄清杜鹃属糙叶杜鹃亚组的分类学问题，完成分类学修订；重建糙叶杜鹃亚组所有物种间的系统发育树，揭示该类群近缘物种间的系统发育关系；探讨利用不同基因组来源的基因组数据对解决辐射演化类群的物种界定和系统发育关系的可行性。本项目不仅能为今后开展杜鹃属的分类学和系统学研究提供理论依据，而且对该属植物资源的保护和可持续利用也具有重要的科学意义。

The precise delimitation of species and the reliable phylogenetic relationship are the basis for studying species evolution and speciation, and the key for biodiversity protection and utilization. The species delimitation and phylogenetic relationship reconstruction of rapid radiation groups is challenging for phylogeneticists. Rhododendron is a species-rich genus and is centrally distributed in southwest of China. The taxonomy and phylogenetic relationships of this genus are unresolved. In this project, R. subsect. Scabrifolia is chose as a case study, the morphological characters for all species within this group will be measured and statistically analyzed on population sampling level. The classification of R. subsect. Scabrifolia will be clarified based on the analysis of phylogenetic relationship, the geographical distribution information and the related ecological data. The phylogenetic tree of R. subsect. Scabrifolia will be reconstructed based on the whole chloroplast genome and RAD nuclear genome data to reveal the phylogenetic relationship among closely related species. The feasibility of using genomic data from different genomic sources to solve the species delimitation and phylogenetic relationship of rapid radiation groups will be discussed as well. This project not only provides theoretical basis for future studies of taxonomy and phylogeny in Rhododendron, but also has important scientific significance for the protection and sustainable utilization of Rhododendron.