6个野生鼠尾藻种群遗传多样性的AFLP分析  

AFLP analysis of genetic diversity in six wild populations of Sargassum thunbergii

作　　者：伊新华[1,2] 李世国[1,2] 何平[3] 侯和胜[1,2] 王丽梅[3] 

机构地区：[1]辽宁师范大学生命科学学院,辽宁大连116029 [2]辽宁省植物生物技术重点实验室,辽宁大连116029 [3]辽宁省海洋水产科学研究院,辽宁大连116023

出　　处：《中国水产科学》2010年第5期922-929,共8页Journal of Fishery Sciences of China

基　　金：辽宁省科学技术计划重大;重点项目子课题(2008203002);大连市科技兴海示范工程(2007BNC065)

摘　　要：运用AFLP分子标记技术对大连庄河石城岛(SCD)、瓦房店将军石(JJS)、长海县大长山(DCS)、旅顺董砣子(DTZ)和旅顺盐场(YC)5个野生鼠尾藻(Sargassum thunbergii)种群与山东蓬莱(PL)1个野生群体的共60个个体进行遗传多样性分析。采用10对引物组合共扩增出条带530条,其中多态性带417条,平均多态性检出比例为78.68%。AMOVA分析显示,大部分的遗传变异(76.58%)存在于种群内,少部分(23.42%)存在于种群之间。遗传分化系数(Gst)为0.2418,与遗传固定化系数(Fst)的值(0.2342)接近,表明鼠尾藻种群内部具有较高的遗传分化,同时种群间的基因流Nm=0.8175,表明基因流动较低。UPGMA聚类分析表明,大连5个野生鼠尾藻种群与山东蓬莱鼠尾藻种群遗传距离较远,明显聚为2支;大连种群中将军石和大长山2个种群聚为1支,遗传相似系数为0.7698,再与董砣子种群聚类到一起;盐场种群单独聚为1支,且与其他种群的遗传相似系数均在0.5830以下。分析结果表明,各鼠尾藻种群内部存在着较高的遗传多样性,而种群间的遗传多样性水平较低,其遗传距离的远近不仅与地理隔离因素有关,高盐等外界环境胁迫也可能起到了一定的作用。鼠尾藻的生殖方式、种群间基因流动的大小以及生长环境的差别可能是其种群分化的主要原因。Amplified fragment length polymorphism（AFLP）was used to assess the genetic diversity of five wild populations of Sargassumthunbergii from Dalian which were Shichengda（oSCD）,Jiangjunsh（iJJS）,Dachangshan（DCS）,Dongtuoz（iDTZ）,Yanchang（YC）and a Shandong population which was Penglai（PL）.Five hundred and thirty loci were obtained with ten combinations of selective primers.Of these loci,417 were polymorphic,accounting for 78.98%of the total.Analysis of molecular variance（AMOVA）revealed that a higher portion（76.58%） of variations existed within populations,while lower portion（23.42%）existed among populations.The G st value was 0.2418,which was consistent with F st（0.2342）,indicating great genetic differentiation within populations.UPGMA dendrogram of the six populations showed they could be clustered into two major groups.One group was from Shandong province,and the other was from Dalian.Among the populations from Dalian,JJS and DCS were clustered into one group,and the coefficient of similarity between them was 0.769 8;but YC was lonely clustered into one group,whose coefficients of similarity with other populations were below 0.583 0.The results showed that there was higher genetic diversity within the six populations,but lower diversity among them,and genetic distance of populations was decided not only by geographical distance but also by external environmental factors such as high salinity and so on.The great genetic differentiation among populations may result from different reproduction forms,little gene flow or different growth environments.

关 键 词：鼠尾藻 AFLP 遗传多样性 遗传距离 

分 类 号：S917[农业科学—水产科学]