东海海域口虾蛄种群遗传多样性

Genetic Diversity of Mantis Shrimp(Oratosquilla oratoria) Populations in the East China Sea

为准确掌握中国沿海口虾蛄（Oratosquilla oratoria）种群遗传结构、合理开发利用其资源,采用线粒体DNA（mt DNA）细胞色素氧化酶Ⅰ（COⅠ）序列分析方法检测东海海域（庙子湖岛、南韭山、大陈岛、南麂岛）口虾蛄种群遗传多样性,并与黄渤海群体和南海群体进行比较分析（基因序列来源于Gen Bank）。经PCR扩增与测序获得100条658 bp的东海海域口虾蛄COⅠ基因序列,基于这些序列分析得到的变异位点数、单倍型数、单倍型多样性指数与核苷酸多样性指数分别为60、60、0.963±0.011和0.005 94±0.000 44,分析认为东海海域口虾蛄具有较高的单倍型多样性和较高的核苷酸多样性。单倍型分子系统树、分子方差分析及两两群体间的遗传分化系数（Fst）分析结果表明,东海海域口虾蛄遗传变异主要来自于群体内（Fst=﹣0.007 78,P〉0.05）,各地理群体间遗传分化不显著,Fst值范围为﹣0.016 53-﹣0.009 08（P〉0.05）,它们可能进行了一定程度的基因交流;通过与黄渤海群体及南海群体基因序列比较分析,口虾蛄东海群体、黄渤海群体与南海群体遗传变异主要来自于群体间（Fst=0.849 71,P〈0.01）,且单倍型分子系统树存在2个显著分化的单倍型类群。东海群体与黄渤海群体间存在显著的遗传分化（Fst=0.884 58,P〈0.01）,而与南海群体间不存在显著的遗传分化（Fst=0.020 44,P〉0.05）,这种遗传结构模式可能与历史上的气候变化及所处海域海洋环境条件相关。建议今后对中国沿海口虾蛄资源进行开发利用时,将黄渤海群体看作一个管理单元,东海群体与南海群体看作一个管理单元。

Mantis shrimp（Oratosquilla oratoria） is an important fishery species in coastal areas of China.To exploit and manage this species scientifically,it is necessary to investigate its genetic diversity and discuss its genetic structure.In this study,the method of sequences analysis of mitochondrial cytochrome oxidase subunit Ⅰ（COⅠ） gene was used to reveal genetic variance of mantis shrimp from the East China Sea（including Miaozihu Island,Nanjiushan,Dachen Island and Nanji island Sea areas,and sample size of each location is 25）.Comparative analysis with that of the Yellow Sea and Bohai Sea population and the South China Sea population（gene sequences were obtained from Gen Bank） was also studied.658 bp of COⅠpartial sequences of mantis shrimp from the East China Sea were obtained by using PCR amplification and sequencing.The results showed that the number of variable site,haplotype,haplotype diversities and nucleotide diversities were 60,60,0.963 ± 0.011 and 0.005 94 ± 0.000 44 respectively in all sequences of four geographical populations from the East China Sea,which indicated that mantis shrimp was characterized by higher haplotype diversity and higher nucleotide diversity（Table 2）.A shallow topology of haplotype neighbor-joining（NJ） tree showed no phylogeographic structure among four geographical populations from the East China Sea（Fig.1）.Analysis of molecular variance（AMOVA） suggested that the genetic variance mainly came from individuals within populations（Fst =﹣0.007 78,P〉0.05）（Table 3）.F-statistics（Fst） among four geographical populations from the East China Sea showed that no significant genetic differentiations were detected（Fst﹣0.016 53 to﹣0.009 08,P〉0.05）（Table 4）.It was supposed that gene exchange in some degree occurred among four geographical populations from the East China Sea.In contrast to gene sequences from the Yellow Sea and Bohai Sea population（30 sequences obtained from Genbank） and the South China Sea population（25 sequences obtained from Genbank）,however,two significant distinct lineages was detected from haplotype neighbor-joining tree（Fig.2）,and analysis of molecular variance suggested the genetic variance mainly came from individuals among populations（Fst = 0.849 71,P〉0.01）（Table 5）.Significant genetic differentiations were detected（Fst = 0.884 58,P〈0.01） between population from the East China Sea and population from the Yellow Sea and Bohai Sea,and the situation between population from the East China Sea and population from the South China Sea is the opposite（Fst =﹣0.020 44,P〉0.05）（Table 6）.The genetic structure pattern of mantis shrimp may be caused by marine environmental conditions or historical climate change.In conclusion,the Yellow Sea and Bohai Sea mantis shrimp should be considered as one stock,while the East China Sea mantis shrimp and the South China Sea mantis shrimp should be considered as one stock in their assessment and management based on this article.