卵形鲳鲹育种群体遗传多样性分析

Genetic polymorphism of breeding populations of golden pompano( Trachinotus ovatus)

利用11个微卫星位点，对海南三亚和广东大亚湾2个卵形鲳够（Trachinotusovatus）育种群体进行了遗传多样性评价和聚类分析。结果显示，海南三亚和广东大亚湾2个卵形鲳够育种群体的平均等位基因（Na）分别为5．0和3．6，平均有效等位基因（Ne）为2．965和2．244，观测杂合度（Ho）分别为0．292—0．814和0．207—0．840，期望杂合度（He）分别为0．307～0．813和0．189～0．761，海南三亚群体中多态信息含量（PIC）为0．014～0．719，平均为0．509，而广东大亚湾群体的PIC为0．168—0．711，平均为0．436。海南三亚群体有5个位点偏离哈迪-温伯格平衡（P〈0．05），广东大亚湾群体有2个位点偏离哈温-伯格平衡；2个群体间的遗传相似系数为0．561，遗传距离为0．578，遗传分化指数（Fst）为0．152。Structure软件分析显示海南三亚和广东大亚湾2个卯形鲳鳞群体各为一支，2个群体间具有较大的遗传分化，可作为2个育种群体管理，2个群体问进行杂交选育预期可获得较好的遗传进展。

We used 11 pairs of microsatellite loci to investigate the genetic polymorphism of two breeding populations of golden pompa- no （ Trachinotus ovatus） in Sanya, Hainan and Daya Bay, Guangdong. The average numbers of alleles （ Na ） at each microsatellite lo- cus of the populations were 5.0 and 3.6, respectively; the average numbers of valid alleles （ Ne ） were 2. 965 and 2. 244, respective- ly. The observed heterozygosities （Ho ） were 0. 292 -0. 814 and 0. 207 -0. 840, respectively; the expected heterzygosities （He ） were 0. 307 -0. 813 and 0. 189 -0. 761, respectively. The PIC value ranged from 0. 014 to 0. 719 in Sanya population with an average of 0. 509, while that of the Daya Bay population ranged from 0. 168 to 0. 711 with an average of 0. 436. In Sanya population, five loci deviated from Hardy-Weinberg equilibrium （ P 〈 0. 05 ）, while only two loci deviated from Hardy-Weinberg equilibrium in Daya Bay population. The Nei＇s genetic similarity coefficient of the two populations was 0. 561 and their genetic distance was 0. 578. The genetic differentiation index of the two breeding populations （Fst） was 0. 152. Structure analysis indicates that the two T. ovatus populations,which had higher genetic differentiation, were divided into two groups and could be managed as two breeding populations. Good genetic progress could be achieved by hybridization between the two breeding populations.