锦江河3种鳜的遗传变异及其多样性评价

为探究锦江河国家级水产种质资源保护区内鳜类遗传变异特征及其多样性水平,基于PCR扩增与测序技术对大眼鳜、斑鳜和中国少鳞鳜3个群体97尾鱼的线粒体控制区序列进行比较分析。结果显示,大眼鳜序列长度为843 bp,无变异位点,只有1种单倍型,斑鳜有852 bp和856 bp两种序列,28个多态位点和11个单倍型,中国少鳞鳜也有845 bp和846 bp两种长度,5个多态位点和5个单倍型;大眼鳜、斑鳜和中国少鳞鳜3种鳜鱼群体内的遗传距离分别为0. 000 0、0. 008 7±0. 002 0和0. 002 0±0. 000 9,单倍型多样度和核苷酸多态性分别为0. 000 0、0. 859 9、0. 736 7和0. 000 0、0. 008 7、0. 002 0。分析表明,3种鳜鱼在终止序列区和保守序列区存在种或属间差异,锦江斑鳜是一个遗传变异大,多样性丰富的稳定种群;中国少鳞鳜虽然单倍型多样度丰富,但遭受过瓶颈效应,导致其核苷酸多样性偏低;大眼鳜遗传组成单一,多样性十分贫乏,推测可能有入侵的养殖群体。锦江系梵净山国家级自然保护区内最大的河流,历史上鳜类资源丰富,但已遭严重的破坏,加强其鳜类遗传资源的研究与保护十分必要。

Genetic diversity and variation of three Sinipercine fishes in Jinjiang River

The aim of this study was to explore the genetic variation characteristics and the level of genetic variation of Sinipercine fishes in the National Aquatic Germplasm Resources Protection Area of Jinjiang River. Based on PCR amplification and sequencing technologies, the mitochondrial control region (D-loop) sequences of Siniperca kneri, Siniperca scherzeri, Coreoperca whiteheadi(3 groups, 97 fish)were compared and analyzed. The results showed that:the sequence length of Siniperca kneri was 843 bp with no variation sites and 1 haplotype was identified; The Coreoperca whiteheadi length sequence had two types of 852 bp and 856 bp, and 28 polymorphic loci and 11 unique haplotypes were identified; The length sequences of Siniperca scherzeri were 845 bp and 846 bp with 5 polymorphic loci and 5 haplotypes were identified. The genetic distance were 0.000 0, 0.002 0±0.000 9 and 0.008 7±0.002 0 in the three groups; The haplotype diversity and nucleotide polymorphism were 0.000 0, 0.859 9, 0.7367 and 0.000 0, 0.008 7, 0.002 0, respectively. The experiment and analysis indicated that there were differences among the termination sequence regions and the conserved sequence regions. For the three populations, Coreoperca whiteheadi was a stable population with great genetic variation and rich diversity. Due to bottleneck effect, although the Siniperca scherzeri had rich haplotype diversity, but had low nucleotide diversity; Siniperca kneri had single hereditary composition, and diversity was very poor. Presumably, there may be a invasive breeding population. Jinjiang, as the biggest river of Fanjing Mountain National Nature Reserve area, once with rich resources of the Sinipercine, but had been badly damaged. It is necessary to strengthen the research and protection of the genetic resources.