基于形态和分子标记的三种鲭科鱼类鉴别新方法

New identification methods for three Scombridae fishes based on morphological and molecular markers

为找到日本鲭(Scomber japonicus)、澳洲鲭(S.australasicus)和羽鳃鲐(Rastrelliger kanagurta)这三种鲭科鱼类鉴别的新标记,采用形态框架等形态分析方法和线粒体标记的方法开展研究。共分析采自海南的33 ind样本,其中日本鲭19 ind,澳洲鲭9 ind,羽鳃鲐5 ind。形态判别分析显示,利用2个可量参数(体高和眼径)或者3个框架参数[D(2-3)、D(3-5)、D(2-4)]构建的判别公式均能鉴别这三种鲭科鱼类,判别准确率均为100%。通过PCR扩增和测序,获得三种鲭科鱼类的线粒体细胞色素b(Cytb)和控制区(D-loop)序列。经对位排列,得到33 ind样本Cytb和D-loop的一致序列分别为1 118 bp和846 bp。Cytb基因共检出17个单倍型,变异位点195个,其中10个固定位点是日本鲭所特有,8个固定位点是澳洲鲭所特有,147个固定位点为羽鳃鲐所特有;D-loop序列共得到27个单倍型,变异位点239个,其中13个固定位点为日本鲭所特有,10个固定位点为澳洲鲭所特有,182个固定位点为羽鳃鲐所特有。这些固定位点可以作为三种鲭科鱼类鉴别的分子标记。

Scomber japonicus,S.australasicus,and Rastrelliger kanagurta are three economic fishes in family Scombridae.In order to improve the management and sustainable utilization of these three species,we developed new identification markers from the point of morphology and molecular biology.Thirty-three individuals of these three species,S.japonicus 19,S.australasicus 9,R.kanagurta 5,were collected from Hainan province.Discriminant formula were constructed by using two morphometric（body depth,eye diameter） or three truss system parameters（D（2-3）,D（3-5）,D（2-4））,and the individuals could be identified with 100% identification accuracy.The cytochrome b（cytb） and D-loop sequences of 33 individuals were obtained by using PCR amplification and sequencing,respectively.The consensus sequences of cytb and D-loop were 1 118 bp and 846 bp after alignment.For cytb,17 haplotypes were defined and 195 variable sites were found.Among the variable sites,10 sites were unique fixation sites for S.japonicus,8 for S.australasicus,and 147 for R.kanagurta.For D-loop,27 haplotypes were detected and 239 variable sites were found.Among them,13 sites were unique fixation sites for S.japonicus,10 for S.australasicus,and 182 for R.kanagurta.These fixation sites could be used as the molecular markers for the identification of these three Scombridae fishes.