基于线粒体COI基因的南海浮游介形类斜突浮萤(Proceroecia procera)单倍型与种群遗传结构研究  

Genetic structure and haplotype pattern of marine planktonic ostracod Proceroecia procera from the South China Sea based on the mitochondrial COI gene

作　　者：徐磊 季莹莹 黎红 杜飞雁[1,3] XU Lei;JI Yingying;LI Hong;DU Feiyan(South China Sea Fisheries Research Institute,Guangzhou 510300,China;College of Marine Sciences,Shanghai ocean university,Shanghai 201306,China;Guangdong Provincial Key Laboratory of Fishery Ecology and Environment,Guangzhou 510300,China)

机构地区：[1]中国水产科学研究院南海水产研究所,广州510300 [2]上海海洋大学海洋科学学院,上海201306 [3]广东省渔业生态环境重点实验室,广州510300

出　　处：《生态科学》2019年第5期15-22,共8页Ecological Science

基　　金：中国水产科学研究院南海水产研究所中央级公益性科研院所基本科研业务费专项资金资助(2017YB26)

摘　　要：介形类是一类小型的双壳甲壳类动物,其海洋浮游种类就超过200余种,是海洋浮游动物中主要组成部分,也是海洋生态系统中物质循环与能量流动的关键环节。以线粒体细胞色素氧化酶亚基I(mtCOI)基因为标记,分析南海浮游介形类中的广布种斜突浮萤(Proceroecia procera)的单倍型多样性与种群遗传结构在空间上的分布,并结合环境选择压力对种群的遗传多样性与结构分化的影响。结果显示,38个个体共检出18种单倍型,广布的单倍型在6个种群中都有分布,说明P.procera种群可以实现远距离扩散,最远超过700km。P.procera种群呈现中度的遗传分化(平均FST=0.186)。种群间遗传分化系数与地理距离无相关性(r=0.17,p=0.15),种群未呈现空间距离隔离。远距离分布的单倍型并没有带来强劲的基因流,相邻种群间甚至呈现出明显的遗传分化。RDA分析结果显示,空间与环境并不是决定P.procera种群遗传结构的主要因素,推测历史上种群扩展带来的拓殖隔离可能是主要解释。Ostracods(Crustacea,Ostracoda)are small bivalved crustaceans,contributing over 200 described species to the marine zooplankton community.They are widely distributed and are relatively abundant components of the mesozooplankton,playing an important role in the transport of organic matter to deep layers.In this study,based on the mitochondrial COI gene analysis,we explored the population genetic structure and haplotype pattern of Proceroecia procera which was the dominant species of ostracods in the South China Sea.We aimed to detect the population genetic structure of ostracods at medium spatial scales in the absence of physical barriers.Our data provided evidence of the importance of both long-distance dispersal as well as genetic isolation in determining the seascape genetic structure of this species.Our data suggested that P.procera could achieve long distance dispersal and specific haplotypes were successful in colonizing habitats from south area to central area in South China Sea.A total of 18 haplotypes were defined from 38 individuals,with most of them being existing only one time.The dominant haplotype was found in six sampling sites.The largest distance between two sampling sites harbouring this haplotype was more than 700 km.Our findings of long distance dispersal in the South China Sea combined with mild genetic differentiation among populations(average FST=0.186)were in line with a scenario where population genetic structure was strongly impacted by colonization patterns.The seascape genetic structure of P.procera in the South China Sea reflects both the importance of long distance dispersal as well as of reduced levels of gene flow,likely caused by colonization events followed by demographic expansions.

关 键 词：介形类 遗传分化 空间距离隔离 COI基因 南海 

分 类 号：Q14[生物学—生态学]