基于细胞色素b基因河鲈养殖群体与野生群体遗传多样性分析

An analysis of the genetic diversity based on the mitochondrial cytochrome b gene sequence of wild and cultivated populations of Perca Fluviatilis

利用线粒体DNA细胞色素b基因的421 bp部分序列对北屯、乌伦古湖、博斯腾湖3个野生河鲈(Perca fluviatilis)群体和北湖、五家渠2个养殖河鲈群体序列多样性与种群遗传结构进行分析。结果表明:100个个体中检测到7个单倍型,变异位点10个,其中野生群体60个个体检测到9个变异位点和6个单倍型,养殖群体40个个体共检测到8个变异位点和4种单倍型;野生群体平均单倍型多样性和平均核苷酸多样性(Hd=0.496±0.121,Pi=0.002 53±0.001 54)高于养殖群体(Hd=0.416±0.127,Pi=0.001 23±0.001 13),分子方差分析揭示,98.74%的遗传变异性出现在种群内个体间。群体间的FST分析揭示野生群体和养殖群体分化程度较低(0.05<FST<0.15)。分子系统树和单倍型网络图分析也表明,河鲈单倍型间关系较近,野生群体和养殖群体不存在显著分化。

In this study,partial cytochrome b gene of the 421 bp mitochondrial sequences were used to analyze the genetic diversity and structure of the Perca fluviatilis from three natural populations( Beitun,Wulungu Lake and Bosten Lake) and two cultivated populations( North Lake and Wujiaqu). The results showed that 10 variable nucleotide sites and 7 haplotypes were detected in 100 individuals. Among them,9 variable sites and 6 haplotypes were found in 3 natural populations of 60 individuals. 8 nucleotide sites and 4 haplotypes were found in 2 cultivated populations of 40 individuals. The average haplotype diversity and nucleotide diversity of the cultivated populations( Hd= 0. 416 ± 0. 127,Pi= 0. 00123 ± 0. 00113) were just a little below that of natural populations( Hd= 0. 496 ± 0. 121,Pi= 0. 00253 ± 0. 00154). AMOVA analysis demonstrated that 98. 74% of the variance occurred among individuals within populations. The pairwise fixation index( FST) revealed a low degree of genetic differentiation between the natural and cultivated populations( 0. 05 < FST< 0. 15). Neighbor- joining tree and Median- joining network of P. fluviatilis also showed natural populations and cultivated population had close relation in haplotypes,and there was no significant differentiation between natural and cultivated populations.