| The genetic diversity of wild Epinephelus coioides population, collected from coastal waters in South China Sea, and cultured E.coioides population in Hainan province were analyzed based on Simple Sequence Repeat (SSR) and Amplified Fragment Length Polymorphism (AFLP) markers. The results provide reference for the protection of E.coioides resources and genetic breeding studies. The results were summarized as follow:1. The genetic variations of wild population and cultured population of E.coioides were assessed at 19 SSR loci. There were 15 polymorphic loci, Polymorphism of loci was 78.95%. A total of 75 alleles were detected. The mean number of alleles at each polyporphic locus was 3.95.The number of mean valid alleles of cultured was 3.1053 and the wild population was 3.9474. The number of effective alleles in cultured populations was 2.1677 and wild population was 2.5338. The Ho values of two populations were 0.6875 and 0.7061. The He values were 0.4215 and 0.4803. The genetic distance and genetic similarity coefficient (Gst) were 0.0208 and 0.9794 and Fst was 0.0157. The results show Genetic differentiation coefficient was low between wild population and cultured population in E.coicides. The cultured population shows lower genetic polymorphisms than wild population, but the Genetic diversity levels in two E.coioides populations both were high.2.9 AFLP primers were used to investigate the genetic variation in both two populations of E.coioides.500 loci were detected in the study, and the segments were ranged from 67 to 500bp. There were 421 polymorphic loci, which polymorphic for 84.20% in all the loci.76 loci among the 421 polymorphic loci were 100% dominance for two populations, which counted for 15.20%; 126 loci which counted for 25.2% were recessive in culture population, while in wild population they showed some dominant individuals. The mean effective number of alleles(ne), genetic diversity coefficient(H), Shannon information index(I), the genetic distance and genetic similarity coefficient of culture and wild populations of E.coioides were 1.3520 and 1.8320,1.1878 and 1.4166,0.1114 and 0.2449,0.1689 and 0.3726, 0.0582 and 0.9435. The Ht, Hs, Gst and Nm values of two populations were 0.2036,0.1782,0.1250 and 3.4997, respectively. The results indicate the level of genetic diversity was high in two populations of E.coioides. The total genetic variation was evolved from the same population.The SSR and AFLP results in E.coioides indicate the same conclusion:the wild population shows higher genetic polymorphism than cultured population, moreover the genetic differentiation was small in the two populations. Relatively the genetic polymorphism in wild Epinephelus coioides population, come from coastal waters in South China Sea, and cultured E. coioides population in Hainan were higher than the others related groupers. There were better germplasm resources of Epinephelus coioides in Hainan. |
