基于基因组重测序研究莲属植物的物种形成及分化机制

莲属为古老的水生被子植物之一，同时也是重要的水生经济作物。该属现存两物种（莲与美洲黄莲）呈现大陆间的间断分布模式，而种内呈现出分布于不同气候带且在形态上具有明显分化的生态型（热带莲和温带莲）。另外，经人工栽培已培育出多个莲品种。为了了解莲属植物特殊的地理分布模式的成因以及莲栽培品种在人工选择下的分化机制，本项目采用基因组重测序技术，通过对世界分布范围内莲属植物的广泛取样，从基因组的层面上，对莲属两物种的间断分布格局的成因，对莲两种生态型的适应性分化机制以及对莲栽培品种与其野生植物的比较基因组学等进行研究，揭示隔离分化、气候驱动、自然选择及人工选择在莲属植物物种形成及分化过程中的作用，为我们全面深入理解莲属植物的物种形成及分化机制提供资料，也为该经济作物的遗传和基因工程育种提供重要的理论。

Nelumbo, an ancient genus, comprises only two extant species, N. nucifera (Asian sacred lotus) and N. lutea (American lotus). These two species disjunctly distributed in East Asia, North Australia, and North America. The sacred lotus has a unique geographical distribution pattern, such as temperate zone and tropic zone distributions. In each climate zone, there distributed a distinct ecotype (temperate lotus and tropic lotus). In addition, the lotus plant is one of the important aquatic crops and is often cultivated for horticulture, food or medicine purpose. In order to understand what factors shaped the unique geographic distribution pattern and how the artificial selection affect the genetic differentiation between the cultivated and wild lotus, in this study, using genome resequencing method, we study the biogeography of the two disjunct distributed species, the adaptive genomics of two ecotypes of the sacred lotus, and the comparative genomics of the cultivated and wild lotus. We will reveal the roles of geographic isolation, historical climate changes, natural selection and artificial selection in shaping the process of speciation and diversification of Nelumbo. The insights gained in this study will not only enrich our knowledge on speciation and diversification of the genus Nelumbo, but also provide some baseline data for the genetic breeding of this economic important crop.