典型荒漠植物泡果白刺(Nitraria sphaeocarpa)的谱系地理研究

Nitraria sphaeocarpa is a typical desert plant in northwestern China, it plays important role in the desert flora and vegetation of northwestern China. This project attempts to investigate the genetic diversity, phylogeographical structure, original haplotype, diversification time and age, events of dispersal, migration and distribution fragment etc. in terms of the distribution of this species namely, along southern slope Tianshan-Kashigar-northern slope Kunlun-Altun, Hexi Corridor, and Alshan. We preliminarily presume that the intense uplift of Qinghai-Xizang Plateau and consequently enhanced aridifization in northwestern China, the climate fluctuation during glaciation and inter-glaciation period and expansion of Taklimakan Desert, should be the driving factors to the evolution and speciation of Nitraria sphaeocarpa. These hypotheses would be verified from this project. Consequently, this study should has the significance for the plant geography of arid northwestern China.

泡果白刺是我国西北干旱区典型的荒漠植物，在植物区系和植被中有重要作用。本项目研究泡果白刺沿塔里木盆地外围的天山南坡-喀什-昆仑北坡-阿尔金山，河西走廊和阿拉善的遗传多样性和谱系地理结构，泡果白刺的原始单倍型、分化时间、扩散迁移方式，泡果白刺的进化与第三纪末期以来的青藏高原的强烈隆升并加剧的西北地区干旱化，天山、昆仑第四纪冰期气候波动，塔克拉玛干沙漠的扩张等的关系。这些研究，对干旱区的植物地理有重要意义。

泡果白刺是我国西北干旱区典型的荒漠植物，在植物区系和植被中有重要作用。本项目按照原定计划，对环塔里木盆地的天山-昆仑-阿尔金山，哈密盆地，河西走廊和阿拉善进行居群采集约19个，进行野外采集、形态变异观察，收集约220个体的分子实验材料。筛选了两个叶绿体基因trn H-psb A 和 rpl32-trn L进行分析。发现12个单倍型haplotype，主要分布在东部的哈密盆地、河西走廊和阿拉善荒漠。遗传变异主要发生在居群间、9个地理群间。根据分子钟假设和生态位模型分析，推断末次间冰期，由于气候变湿变暖，在河西走廊的分布发生了扩张；在末次大冰期，泡果白刺发生了大的收缩和片段化。这些研究，对干旱区的植物地理提供了新的证据。并结合以前的工作，发表了1篇SCI论文。