2018年12月16日 星期日
新疆濒危植物半日花居群的遗传变异及遗传结构分析
Analyses on genetic variation and genetic structure of populations of endangered plant Helianthemum songaricum in Xinjiang
2017年 第26卷 第4期 页码[67-73]    下载全文[1MB]  
摘要

利用3个叶绿体微卫星多态性引物(包括mtrnSf-trnGr、mtrnL2-trnF和mtrnL5-trnL3)对新疆地区半日花(Helianthemum songaricum Schrenk)9个居群〔分别位于伊犁河谷的军马场(JMC)、黑山头(HST)、科克苏(KKS)、种羊场(ZYC)、科博(KB)、龙口(LK)、喀拉布拉(KLBL)和拜什墩(BSD)以及河谷北部的博乐(BL)〕92个单株的叶片总DNA进行了扩增,在此基础上,对各居群的遗传变异、地理分布、遗传多样性和遗传结构进行了分析。结果表明:3个叶绿体微卫星多态性引物共扩增出6个多态性位点;经分析,得到H1、H2、H3和H4 4个单倍型,其中,H1单倍型分布在JMC、HST、KKS、ZYC、KB和KLBL居群,H2单倍型仅分布在JMC居群,H3单倍型分布在LK和BL居群,H4单倍型仅分布在BSD居群。9个半日花居群总的遗传多样性指数较高(0.583),但居群内的遗传多样性指数却很低(0.040),居群间的遗传分化系数为0.932。主坐标分析(PCoA)将9个半日花居群划分成3个群体,其中,BSD居群单独为1个群体,BL和LK居群为1个群体,其余6个居群为1个群体;而亲缘关系树状图将这9个居群分成2支,其中,BL、LK和BSD居群为1支,其余6个居群为1支,说明BL、LK和BSD居群明显有别于其他居群。分子方差分析结果表明:半日花95.61%的遗传变异发生在群体间。Mantel检验结果表明:各居群间遗传距离与地理距离的相关系数为0.324,说明半日花居群间遗传距离与地理距离存在一定程度的正相关。研究结果显示:新疆地区半日花居群间发生了明显的遗传分化,并存在一定程度的地理隔离,这可能与小居群的遗传漂变和近交效应及居群间的地理障碍有关。建议对新疆地区半日花的全部居群、个体和原始生境进行保护,并对其天然居群采取复壮、迁地保护和划分居群管理单元等保护措施。

Abstract

Total DNA in leaves of 92 individuals from nine populations 〔located in Junmachang (JMC), Heishantou (HST), Kekesu (KKS), Zhongyangchang (ZYC), Kebo (KB), Longkou (LK), Kalabula (KLBL), and Baishidun (BSD) of Yili valley, and in Bole (BL) of northern Yili valley, respectively〕 of Helianthemum songaricum Schrenk in Xinjiang region were amplified by using three chloroplast microsatellite polymorphic primers (including mtrnSf-trnGr, mtrnL2-trnF, and mtrnL5-trnL3). On the basis, genetic variation, geographic distribution, genetic diversity, and genetic structure of each population were analyzed. The results show that six polymorphic sites are amplified by using three chloroplast microsatellite polymorphic primers. Four haplotypes of H1, H2, H3, and H4 are obtained after analysis, in which, haplotype H1 distributes in JMC, HST, KKS, ZYC, KB, and KLBL populations, haplotype H2 only distributes in JMC population, haplotype H3 distributes in LK and BL populations, and haplotype H4 only distributes in BSD population. Total genetic diversity index of nine populations of H. songaricum is relatively high (0.583), while genetic diversity index within population is relatively low (0.040), and the genetic differentiation coefficient among populations is 0.932. Nine populations of H. songaricum are divided into three groups by using principal coordinate analysis (PCoA), in which, BSD population alone is a group, BL and LK populations are a group, and other six populations are a group. While the nine populations are divided into two branches by using phylogenetic tree, in which, BL, LK, and BSD populations are a branch, and other six populations are a branch, meaning that BL, LK, and BSD populations are obviously different from other populations. Molecular variance analysis result shows that 95.61% of genetic variation of H. songaricum occurs among groups. Mantel test result shows that the correlation coefficient of genetic distance with geographic distance among populations is 0.324, indicating that there is a certain degree of positive correlation of genetic distance with geographic distance among populations of H. songaricum. It is suggested that there are obvious genetic differentiation among populations of H. songaricum in Xinjiang region, as well as a certain degree of geographic isolation, which is probably associated with genetic drift and inbreeding effect of sub-population and geographic barrier among populations. All populations, individuals, and original habitats of H. songaricum in Xinjiang region are proposed to protect, and protective measures of rejuvenation, ex situ conservation, and dividing population management unit, etc. are recommended for preserving its natural population.
 

关键词半日花; 新疆地区; 遗传变异; 遗传结构; 叶绿体微卫星技术(cpSSRs
Key wordsHelianthemum songaricum Schrenk; Xinjiang region; genetic variation; genetic structure; chloroplast microsatellite technology (cpSSRs)
作者苏志豪1, 李文军1, 卓立2, 姜小龙3
所在单位1. 中国科学院新疆生态与地理研究所 干旱区生物地理与生物资源重点实验室, 新疆 乌鲁木齐 830011;
2. 新疆师范大学图书馆, 新疆 乌鲁木齐 830054; 3. 上海辰山植物园, 上海 201602
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基金项目新疆维吾尔自治区自然科学基金资助项目(2014211A073)