黄檗属植物的谱系地理学与物种形成研究

东亚地区温带植物物种多样性非常高，使其成为多样性的形成和维持研究的热点区域。其中，第四纪气候变化和复杂地形对分布于东亚地区第三纪孑遗种群的地理分布格局和物种形成机制的影响，是当前研究的热点。本项目将以东亚特有属黄檗属所有物种为研究对象，分析其属内物种形成过程，地理隔离和生态分化选择所起的作用。项目拟采用叶绿体、核微卫星和核单拷贝基因等多套分子标记，基于种群数据构建黄檗属各形态分类种和种群间的系统发育树，评价属下种间关系，追溯类群时空分化的历史，估计系统树上各主要分支节点的分化时间和期间的基因流水平，揭示黄檗属植物的物种形成过程。本项目的研究结果将有助于理解东亚植物区系现存分布格局的起源和演化，有助于理解第四纪气候变化对东亚暖温带落叶阔叶林树种物种形成的影响，同时为第三纪孑遗的黄檗属植物提供保护生物学方面的资料。

East Asia sustains extreme high diversity of temperate flora, which leads to a key question in ecology about its origin and maintenance of high biodiversity. It is a hot issue now about the influence of Quaternary climate change and complicated physiographic conditions on the distribution and speciation of Tertiary relict populations in East Asia. This project will focus on all species of the East Asia specific genus, Phellodendron, and analyze the process of speciation in the genus, the role of geographic barrier and ecological divergence selection. The project will gain and analyze multiple nuclear single copy genes, nuclear microsatellites and chloroplast fragments. A phylogenetic tree will be constructed base on population samples of all morphological species. We will assay the relationship between species, trace the time and space issue of population divergence, time the major clade and estimate the level of gene flow along the divergence. All the above analysis will uncover the process of speciation in Phellodendron. The outcome of this project will help to understand the origin and evolution of East Asia plant flora, as well as the influence of Quaternary climate change on the formation of warm temperate deciduous forest tree species. The study could also provide useful guide for the conservation of all the Tertiary relict species of the genus Phellodendron.