EGI OpenIR  > 研究系统  > 荒漠环境研究室
中国西北干旱区裸果木遗传多样性分析及裸果木属的进化历史研究
贾舒雯
学位类型博士
导师张明理
2016
学位授予单位中国科学院大学
学位授予地点北京
学位专业植物学
关键词裸果木 裸果木属 遗传多样性 微卫星引物 干旱化
摘要本研究应用叶绿体,核基因和微卫星三种分子标记分析中国西北干旱区裸果木(Gymnocarpos przewalskii)的遗传多样性和谱系地理结构。同时利用叶绿体和核基因分析裸果木属(Gymnocarpos)的进化历史。 (1)裸果木的遗传结构与居群动态分析 以裸果木为研究对象,探索其在中国西北干旱区的谱系地理结构。在本研究中一共采集了来自21个居群的194个样品。应用两个叶绿体片段(rps16, psbB-psbI)和一个核基因片段ITS对裸果木的所有样品进行测序。应用谱系地理学方法结合生态位模型分析裸果木的空间基因结构和居群历史动态。研究结果发现裸果木具有很高的遗传多样性(cpDNA: h = 0.8442,π = 0.008417; ITS: h = 0.8477,π = 0.008825)。单倍型或基因型分析表明,在裸果木的分布区内有很多私有单倍型或基因型,在整个裸果木的分布区内没有共享的单倍型或基因型。AMOVA分析表明裸果木居群之间的变异最多发生在组之间。Mental test说明裸果木的遗传距离与地理距离显著相关。裸果木的数据表明裸果木具有显著的谱系地理结构。分化时间分析表明,裸果木的分化时间发生在更新世,与第四纪冰期循环的时间相对应。我们的分析表明,裸果木的进化历史与第四纪的气候震荡有着紧密的联系。 (2)裸果木的微卫星引物开发及遗传多样性分析 在本研究中,利用磁珠富集法,首次开发了17对裸果木的微卫星引物。其中12对具有良好的多态性。应用其中6对多态性微卫星引物分析裸果木的遗传多样性。分析结果表明,裸果木有很高的遗传多样性(Ho = 0.5624,He = 0.7400)。根据Nei氏遗传距离构建的聚类树和贝叶斯法的分类分析表明,裸果木居群的分组与居群之间的地理距离相关。Mental Test分析也证明裸果木的遗传距离与地理距离显著相关。裸果木居群分为三组:第一组由位于裸果木分布区最西部的居群组成,全部来自塔里木盆地;第二组的居群几乎位于裸果木分布区的中间位置,由来自塔里木盆地、哈密盆地和河西走廊的居群组成;第三组的居群位于裸果木分布区的最东部,由来自河西走廊和阿拉善荒漠的居群组成。AMOVA分析表明,裸果木组间有很高的遗传分化,组内居群间分化较小,样品个体间分化较大。研究结果表明,有性繁殖可能是维持裸果木高遗传多样性的重要原因。 (3)裸果木属进化历史的研究 在本章的研究中,采用裸果木属中的八个种(共十个种)的样品为代表分析这个属。应用两个叶绿体片段(rps16和psbB-psbH)和一个核基因(ITS)片段对所有的样品测序。系统发育分析的结果显示,裸果木属是一个单系属,属内的物种分为两个组:第一个组是由两个广布种G. sclerocephalus和G. decandrus组成,这两个种主要分布地为北非及其周边地区;第二组由剩下的六个地区特有种组成,主要分布于阿拉伯半岛南部及其邻近的印度洋岛屿和中国西北部及蒙古国。分化时间分析显示裸果木属的形成时间大约在31.33 Ma,邻近始新世向渐新世的过度时期。裸果木属开始分化的时间是6.69 Ma,大约在晚中新世。裸果木属内的物种的分化时间几乎都发生在上新世与更新世。分化时间分析表明裸果木属的多样化受到自中新世以来气候变化的显著影响。祖先栖息地重建分析表明,裸果木属的祖先分布区为阿拉伯半岛南部及其邻近的印度洋岛屿。
其他摘要In this study, we used chloroplast markers, nuclear marker and microsatellite to analyze genetic diversity and phylogeography of Gymnocarpos przewalskii. We analyzed evolutionary history of Gymnocarpos using chloroplast and nuclear markers. (1)The analysis of genetic structure and population dynamics of G. przewalskii. In this study, we used G. przewalskii as a model to address the evolutionary history and current population genetic structure of this species in Northwestern China. We sampled 194 individuals from 21 populations, and sequenced two chloroplast DNA fragments (rps16, psbB-psbI) and one nuclear DNA fragment (ITS)for all individuals ofG. przewalskii. Phylogeographical methods and species distribution models were used to explore its spatial genetic structure and population history. High genetic diversity (cpDNA: h = 0.8442,π = 0.008417; ITS: h = 0.8477,π = 0.008825) was identified in almost all populations. Most haplotypes/ribotypes were private to particular regions. Mental test detected significant correlation betweengenetic distance and geographic distance. Divergence between most lineages of G. przewalskii occurred in the Pleistocene. Overall, our results clearly show that climate oscillation during Pleistocene significantly affected the evolution of the species. (2)Development of microsatellite primers and analysis of genetic diversity of G. przewalskii. In this study, seventeen microsatellite markers for the species were firstly developed using enrichment library protocols, twelve of them were polymorphic. Six polymorphic microsatellite markers were used to analyzegenetic diversity of G. przewalskii.Microsatellite analysis of G. przewalskii showed that this species has a high genetic diversity in the distribution regions of China(Ho = 0.5624, He = 0.74). Mental test, Nei's genetic distance and Bayesianmethodproved that the genetic distance and geographic distance of G. przewalskii were significantly correlated. The population of G. przewalskii were divided into three groups: the first group of populationslocated in the western distribution area of G. przewalskii, consists of all individuals from the Tarim Basin; the second group is almost located in middle position of distribution area, individuals come from the Tarim Basin, Hami basin and Hexi Corridor; the third group consists of population located in the eastern distribution zone, individuals come from the Hexi Corridor and Alashan desert. AMOVA analysis shows that the most variation of G. przewalskiiis within individuals. The results indicated that sexual propagation may be an important factor to maintain high genetic diversity of G. przewalskii. (3)The analysis of biogeography of Gymnocarpos In present study, we sampled eight species within the genus and sequenced two chloroplast regions(rps16 and psbB-psbH), and the nuclear rDNA(ITS). The results of the phylogenetic combined analyses corroborated to Gymnocarpos as monophyletic, in which two well-supported clades are recognized: clade 1 includes Gymnocarpos sclerocephalus and G. decandrus - that is a mainly North African group, whereas clade 2 comprises the remaining species included, that are distributed mainly in the Southern Arabian Peninsula. Molecular dating analysis revealed that the divergence age of Gymnocarpos was ca. 31.33 Ma near Eocene and Oligocene transition boundary, the initial diversification within Gymnocarpos dates to ca. 6.69 Ma in the mid-late Miocene, and the intraspecific diversification mostly occurred during the climatic oscillations of Pleistocene. Ancestral area reconstruction suggested that the Southern Arabian Peninsula was the ancestral area for Gymnocarpos. Our conclusions suggest that the aridification since mid-late Miocene significantly affected the diversification of the genus in these areas.
学科领域植物学
语种中文
文献类型学位论文
条目标识符http://ir.xjlas.org/handle/365004/14766
专题研究系统_荒漠环境研究室
作者单位中科院新疆生态与地理研究所
推荐引用方式
GB/T 7714
贾舒雯. 中国西北干旱区裸果木遗传多样性分析及裸果木属的进化历史研究[D]. 北京. 中国科学院大学,2016.
条目包含的文件
条目无相关文件。
个性服务
推荐该条目
保存到收藏夹
查看访问统计
导出为Endnote文件
谷歌学术
谷歌学术中相似的文章
[贾舒雯]的文章
百度学术
百度学术中相似的文章
[贾舒雯]的文章
必应学术
必应学术中相似的文章
[贾舒雯]的文章
相关权益政策
暂无数据
收藏/分享
所有评论 (0)
暂无评论
 

除非特别说明,本系统中所有内容都受版权保护,并保留所有权利。