物种界限的界定与划分一直是困扰分类学的重要问题之一。对物种概念的理解有助于更好的理解生物多样性的形成和维持。生态因素在物种形成研究中的作用越来越显著，但是物种自身响应生态选择压力的机制研究却很少。申请者前期研究发现百合属中一个我国特有的岷江百合单系分支包含的6个物种有很近的遗传距离却在形态上区别显著。而这样的差异和传粉者的选择直接相关，是典型的生态诱导物种分化形成新物种的实例。本项目拟在澄清群体遗传结构、排除杂交及基因渐渗的干扰基础上，采用全长转录组作为参照，对这个特有的类群6个物种的转录基因组进行比较研究，进而阐明与花部结构变化相关的分子机制。本研究的主要目的包括：1）对岷江百合等6种百合属姊妹类群的分布式样、群体遗传结构进行解析，揭示长江中上游地区物种分化模式；2）以该类群为例，对快速物种形成的分子机制在基因组水平上进行解析和揭示，并为物种形成和物种界限研究提供新的实例。

The delimitation and discrimination of species boundaries is one of the most important questions that confound taxonomists in botany. The recognition of species notion will promote the understanding of formation and persisting of biodiversity. In recent, the ecological factors were found contributed more and more significant in speciation process, yet the mechanism that how species reacted to ecological pressures is seldom studied. Previous research on the genus Lilium of the author recovered a monophyletic clade named Leucolirion distributed over up and middle Yangtze River which included six species have very closed molecular affinity, however, varied a lot on the morphology and can divided easily into two types by flower. These two flower types are proved to be directly related to the pollinator preferences. This is a typical pattern of ecological induced speciation. In this study, we use this endemic monophyletic group as model to do such researches as 1) clarify its population genetic structure and excluded the affections might be caused by hybridization and introgression; 2) use full-length transcriptome method to make references and then compare the differences of these six species with transcriptome data, which is hope to recover the genetic bases of flower morphology variation. This program are aimed to answer these questions as 1) the species mechanism and distribution pattern of the up and middle Yangtze River, and 2) using this endemic group as model to try to discover the mechanism of speciation on the genome level and provide a new case study on species boundary and species delimitation.