厦门海域桡足类卵的分子鉴定

Preliminary Study on the Molecular Identification of Copepod Eggs in Xiamen Bay

由于传统物种分类技术无法快速有效地鉴定大部分桡足类休眠卵的种类,急需建立具有发展前景的分类鉴定方法.根据本实验室建立的快速鉴定沉积物中桡足类休眠卵的方法,在厦门海域采集几种常见桡足类成体及其新产出的卵,通过测定28SrRNA上约300bp的目标序列,查找比对Genbank中同种和同属桡足类的序列,对该方法种类鉴定的准确性进行验证;同时还采集并分离了厦门海域沉积物中的单个桡足类卵,将测得目标序列与已知种类序列进行比对分析,建立Neighbor-Joining系统发生树.研究结果表明,该方法可以准确地鉴定厦门海域桡足类的成体、新产出的卵以及沉积物中休眠卵的种类,目标片段序列的相似度≥98%和≥95%可以分别作为判定同种和同属的标准.

In this research several copepod freshly spawned eggs and resting eggs were identified and analyzed in Xiamen Bay,based on an established method of fast identify copepod eggs in sediments.DNA barcoding is an alternative approach to identify copepod species and improve the accuracy in analyzing copepod samples.The partial 28S rRNA（～300 bp） sequence was valid in copepod species identification,and the sequence was used to constructed a Neighbor-Joining tree which showed that freshly spawned eggs and resting eggs of copepod in Xiamen Bay can be accurately identified by this method,and the similarity rate of sequences ≥98% and ≥95% represented the same species and the same genera respectively.This method can be widely applied in copepod egg banks studies for identifying copepod species and their composition and distribution.