基于全基因组重测序研究报春苣苔属的物种形成与适应性分化

Karst plants constitute a crucial part of plant diversity and peculiarity in China. However, few of previous studies have focused on the origin and evolution of plant diversity in karsts, especially for the mechanisms underlying the speciation and adaptive divergence. The genus Primulina harbored high level of species richness and most of which are geographically isolated with clear species boundaries. The heterogeneous habitats of karst result in strong natural selection pressure, which confer the Primulina as an ideal system to study the mechanism underlying the diversification of karst species. The successful assembly of Primulina huaijiensis genome provide us opportunity to address the mechanism of speciation and adaptive divergence of karst plants at the whole genome level. In this study, we plan to sequence the whole genomes of 10 populations from four Primulina species. Through the comparative analyses of genetic differentiation, species boundary, gene flow, and demographic history, our study might be able to shed light on the speciation model of karst plants. With further analyses focusing on the genome-wide scanning of selection, we are hopeful to reveal the genetic basis of adaptive divergence among Primulina species.

喀斯特特有植物是我国植物多样性和特有性的重要组成部分，但目前对喀斯特植物多样性的起源与演化，尤其是对物种形成机制和适应性分化的研究非常少。报春苣苔属物种多样性丰富，且多为地理隔离的小种群，有清晰的种群边界。喀斯特异质生境为该属植物的分化提供了强大的自然选择压力，因此报春苣苔属植物是研究喀斯特植物多样性形成与维持机制的理想材料。随着怀集报春苣苔（Primulina huaijiensis）基因组组装的完成，从全基因组水平研究喀斯特植物的物种形成机制和适应性分化得以顺利开展。本研究拟以报春苣苔属4个物种的10个群体为实验材料，基于全基因组重测序获得海量的SNP分子标记，通过分析物种的遗传分化、物种边界、基因流和重建物种分化历史来探索喀斯特植物物种形成机制，并同时通过选择性消除分析定位适应性分化相关基因来探讨喀斯特特殊生境中报春苣苔属植物适应性分化的遗传基础。