基于线粒体COI序列的中国沿海蓝点马鲛遗传多样性  

Genetic variation of Scomberomorus niphonius in the coastal waters of China based on mt DNA COI sequences

作　　者：曹艳[1] 章群[1] 宫亚运 吕金磊[1] 杨喜书 

机构地区：[1]暨南大学生态系,广州510632

出　　处：《海洋渔业》2015年第6期485-493,共9页Marine Fisheries

基　　金：国家自然科学基金(41071034);中央高校基本科研业务费专项资金(21613105);欧盟Erasmus Mundus TECHNO I博士后交流项目

摘　　要：为了解中国沿海蓝点马鲛(Scomberomorus niphonius)的遗传背景以更好地保护和开发利用种质资源,对分布于渤海、黄海、东海和南海海域的6个群体76 ind蓝点马鲛线粒体COI基因712 bp序列进行了测定,并结合Gen Bank中下载的9条南海蓝点马鲛序列,分析其遗传多样性、种群结构和历史动态。共检测到21个变异位点,17个单倍型,总体呈现高单倍型多样性(Hd=0.702±0.044)和低核苷酸多样性(π=0.002 8±0.000 2)的特点,其中渤海、黄海和东海海域的蓝点马鲛群体遗传多样性指数相对较高(Hd:0.695~0.816,π:0.002 7~0.003 3),而南海群体明显偏低(Hd=0.442±0.145,π=0.001 7±0.000 6),推测是由于黄海和东海是中心分布区,而南海是边缘分布区的缘故。AMOVA分析结果显示,群体间(-6.27%^-1.52%)不存在变异,群体内个体间(101.52%~106.56%)的变异是变异的主要来源;群体间遗传分化系数Fst值为-0.138~0.040(P>0.05),遗传距离N_m值为-81.145^-4.134、11.876~146.559,均大于4或小于0,表明群体间不存在遗传分化,不同海域群体间基因交流频繁,这可能与蓝点马鲛分布范围广、具长距离迁移能力、产卵和越冬时均可发生洄游以及鱼卵具漂浮性且为多次性产卵类型等原因有关。聚类分析的邻接树与单倍型网络图上出现的2个分支均在更新世晚期发生过种群快速扩张事件,但蓝点马鲛总体在数据上未呈现出种群扩张现象,可能是2个分支的叠加造成整体核苷酸不配对分析图呈现多峰分布。Genetic diversity is essential to the long-term survival of any species to changing environmental conditions, and can provide insights into tempo-spatial pattern of germplasm diversity of wild organisms, thus studies on genetic diversity of fishes play an important role in the conservation and sustainable exploitation of fishery resources. Japanese Spanish mackerel Scomberomorus niphonius, a member of Scombridae family and Scomberomorus genus, is a pelagic carnivorous fish widely distributed in the coastal waters of China, Korean peninsula and Japan of the northwestern Pacific, it is reported to undertake long-distance migrations during spawn and overwintering. It is a commercially important species in the Northwestern Pacific countries with the main catch in China, despite some recent decline in catches, the yield is still considerably high and relatively stable, especially compared with the sharply decreased catch of other economic fishes. To effectively manage and exploit the valuable fish resources sustainably, more information of its genetic background is needed. In the present study, 712 bp of the mitochondrial cytochrome oxidase subunit I in S. niphonius collected from six sites in the coastal waters of China Sea （ including the Bohai Sea, the Yellow Sea, the East China Sea and the South China Sea）, combined with nine sequences downloaded from GenBank, were used to analyze the genetic diversity, population structure and demographic history. A total of 21 polymorphic sites, seven parsimony informative sites and 17 haplotypes were detected in 85 individuals. In addition, the content of T, C, A and G was 29.5%, 29.2%, 23.9% and 17.4%, respectively. Relatively high levels of haplotype diversity （ Hd = 0.702 ± 0.044 ） and low levels of nucleotide diversity （ 7r = 0. 002 8± 0.000 2 ） for all sites as a whole were found, of which genetic diversity of the Bohai Sea, the Yellow Sea and the East China Sea populations were obviously higher （Ha ：0. 695 -0. 816, π=0.002 7 -0. 003 3） than those in

关 键 词：蓝点马鲛 线粒体COI序列 遗传多样性 中国沿海 

分 类 号：Q349[生物学—遗传学]