Genetic Variations And The Phylogenetic In Some Species Of Sparidae Revealed By RAPD Technique

Random amplified polymorphic DNA (RAPD) technique was applied to assess genetic variations and phylogenetic relationship among two wild populations of Sparus latus (16 individuals) , three wild populations (48 individuals) of Pagrosomus major and Sparus macrocephalus from Jiaozhou Gulf (Qingdao), Taiwan Strait (Xiamen) and Beibu Gulf (Hainan). RAPD technique was also applied to study genetic relationships and the phylogenetic of Sparidae, including Parargyrops edita, Pagrosomus major, Rhabdosargus sarba , Sparus latus and Sparus macrocephalus.Amplification reaction system and thermocycling parameter were optimized by gradient experimentations. Sixty different ten base-pair primers acquired from Operon Technologies, primers KitA, KitR and KitS, were used in the preliminary analyses. Under predetermined optimal reaction conditions, the primers which produced distinct and reproducible bands were chosen for the final analysis. The results were as follows.In the study of populations of S. latus, amplifications with 18 random primers selected from 40 gave 93 reproducible and stable fragments. The similarities of intrapopulation for Fujian population and Zhujiangkou population were 0.8821,0.8785. With the methods of UPGMA and NJ on the basis of genetic distances, the results showed the two populations assembled one branch respectively, and both results were accordant. That indicated there was obvious genetic differentiation between the two populations. They were two different geographical populations.In the study of populations of P. major and S. macrocephalus, amplifications with 32 random primers selected from 60 gave 219 and 200 reproducible and stable fragments for P. major and S. macrocephalus respectively. For the genetic distances of interpopulation, the maximum occurred between Qingdao and Hainan populations; the minimum did between Xiamen and Hainan ones. P. major and S. macrocephalus were accordant in this aspect. For the genetic distances of intrapopulation, the maximum and minimum occurred in Qingdao and Xiamen ones in P. major respectively; the maximum and minimum occurred in Hainan and Xiamen ones in S. macrocephalus respectively. With the methods of UPGMA and NJ in MEGA2.1 on the basis of genetic distances, the results showed Xiamen and Hainan populations assembled one branch first, then did Qingdao population. Both results were accordant, and the result accorded with the geographical distribution , ecological character and sea status along Chinese coast.In the study of species of Sparidae, amplifications with 29 random primers selectedfrom 60 primers gave 200 reproducible and stable bands ranging from 200 to 2500bp. Each species had its own unique bands used for species identification. The molecular phylogenetic trees constructed by UPGMA and NJ methods of MEGA2.1 indicated S. macrocephalus and S. latus belonged to Sparus were the most related while S. macrocephalus and P. edita Tanaka were the least; R. sarba was more related with S. macrocephalus and P. editaTanaka than S. macrocephalus and S. latus. And they agreed with classical taxonomy based on morphological and biochemical characters, hi the matrix of genetic distances among 40 individuals, the max. was 0.8916, majority was 0.5000~0.8500. The result showed RAPD could be used to study the genetic relationships and the phylogenetic of genara.