Random amplified polymorphic DNA(RAPD) technique was employed to detect the DNA polymorphism in 30 individuals of natural population of Pleuronectes yokohamae.20 arbitrary primers selected from 48 primers were used and 148 clear,repeatable RAPD bands were generated in which 94 bands were polymorphic.All the primers are polymorphic primers.Each primer used for the detection could produce 4-13 molecular markers with the average of 7.4.DNA fingerprints vary in length from 200-2 000 bp.The percentage of polymorphic fragments was 63.51%,while the index of Shannon diversity was 0.2824 and the index of gene diversity was 0.1991.Every individual had genetic difference and the genetic distance between individuals was from 0.0148 to 0.1963.Comparing the genetic diversity of Pleuronectes yokohamaes with that of other fishes,the experiment revealed that the genetic diversity of Pleuronectes yokohamae was at middle level.This result will give data for the future study of genetic diversity in Pleuronectes yokohamae.
旨在了解秀丽白虾线粒体16S rRNA基因序列及线粒体16S r RNA基因在虾类物种鉴定及系统分类中的作用,采用PCR特异扩增测序的方法,对秀丽白虾(Exopalaemon modestus)的16S rRNA基因片段进行了分析,并探讨了长臂虾亚科虾类的系统发育关系。结果表明:54尾秀丽白虾16S r RNA基因共发现5种单倍型和8个变异位点。13种长臂虾间的遗传距离在0~0.2614之间,7个属间的遗传距离为0.1344~0.2769。NJ法和ME法构建的系统进化树显示,除洁白长臂虾外,同属的不同种先聚成一支,其中东方白虾和脊尾白虾亲缘关系最近。长臂虾属和小长臂虾属亲缘关系很近,长臂虾属为多起源;推测洁白长臂虾与宽额拟瘦虾之间的分化时间距今约22.34百万年。本研究结果表明,线粒体16S rRNA基因序列不能单独对长臂虾亚科虾类进行物种鉴定,但进行系统分类和亲缘关系分析是可行的。