牙鲆和大菱鲆养殖群体的分子标记和遗传变异

Molecular genetic markers and variations of cultured Paralichthys olivaceus and Scophthalmus maximus

用 16个 10碱基随机引物对养殖牙鲆 (Paralichthysolivaceus)和大菱鲆 (Scophthalmusmaximus)进行基因组随机扩增多态性DNA (RAPD)遗传分析。发现 :( 1)多个引物具有种的特异性扩增带。其中引物S7扩增的 690和 1160bp带 ,引物S2 扩增的 680bp带为牙鲆的种的特异性谱带 ;而引物S7扩增的 653和889bp带 ,引物S2 扩增的 650、870、990及 1161bp带为大菱鲆的种的特异性谱带 ;( 2 )牙鲆和大菱鲆群体内个体间的平均遗传相似度分别为 0 .90 5和 0 .94 5;用SAS软件对群体内个体间的平均遗传相似度的方差分析结果表明 ,在牙鲆群体内存在显著差异 (P <0 .0 5) ,而在大菱鲆群体内则差异不显著 ,表明大菱鲆的种质较单一 ,存在近交衰退的危险 ;( 3)牙鲆和大菱鲆的香农氏遗传多样性指数分别为 2 .735和 3.758。

RAPD was employed to assess the genetic variations between 2 cultured Pleuronectformes species (Paralichthys olivaceus and Scophthalmus maximus). The results show that:(1)Two primers can amplify distinctive bands in 16 polymorphic 10-mer primers. The 690bp and 1 160bp bands amplified by S 7, and the 680bp band by S 2 are the character of P.olivaceus and the 653bp, 889bp bands by S 7, the 650bp, 870bp, 990bp, 1 161bp bands by S 2 are the character of S.maximus. (2) The average genetic similarity index and Shannon's index of phenotypic diversity within 2 species are 0.905 and 2.735 in P.olivaceus and 0.945 and 3.758 in S.maximus. The variances of average genetic similarity between individuals within each species were detected by SAS software.There was significant difference (P<0.05) among the species of P.olivaceus and no such character among the species of S.maximus.(3)Shannon's index of phenotypic diversity is 2.735 in P.olivaceus and 3.758 in S.maximus.