【摘要】 为探讨斑鳢（Channa maculata）自然分布群体的遗传结构和遗传多样性,基于SLAF简化基因组测序技术检测了斑鳢7个群体（广东阳春、广东化州、广西南宁、广西贺州、湖南江华、福建邵武、台湾台北）的SNP标记,并进行遗传学分析。结果显示,共检测出2502887个SNP位点,平均测序深度为20.19X,平均Q30和GC含量分别为95.31%和41.16%。7个斑鳢群体多态性信息含量（PIC）为0.2672～0.2872,期望杂合度（H_e）为0.3304～0.3580,观测杂合度（H_o）为0.2145～0.3393,群体遗传多样性处于中等水平。群体间遗传分化指数(F_st)为0.15300～0.78658,基因流（N_m）为0.24118～0.62035,群体间表现出高度遗传分化状态,台北群体与其他6个群体间遗传分化程度极大(F_st>0.5)。群体遗传结构分析表明,7个群体均单独聚类,遗传结构单一。本研究揭示了不同地区野生斑鳢群体的遗传背景和亲缘关系,对斑鳢种质资源的合理利用和遗传育种工作具有重要的参考意义。在后续的育种工作中,应特别关注不同斑鳢群体间的亲缘关系,以期提高斑鳢亲本质量和育种效率。更多还原

【Abstract】 Channa maculata, an economically significant freshwater fish in China, has been subject to a limited number of population studies. To explore the genetic diversity of naturally distributed populations of C. maculata,single nucleotide polymorphism(SNP) markers were developed and genetically analyzed in seven populations(Yangchun, Guangdong; Huazhou, Guangdong; Nanning, Guangxi; Hezhou, Guangxi; Jianghua, Hunan; Shaowu,Fujian; Taipei, Taiwan) using the simplified genome sequencing technology of SLAF. The findings revealed the detection of 2502887 SNP loci, with an average sequencing depth of 20.19×, and average Q30 and GC contents of 95.31% and 41.16%, respectively. Population genetic structure analysis revealed individual clustering of all seven populations, each with a distinct genetic structure. The polymorphic information content of the seven C. maculata populations was 0.2672–0.2872, the expected heterozygosity(He) was 0.3304–0.3580, and the observed heterozygosity(Ho) was 0.2145–0.3393. The populations had a medium level of genetic diversity. The genetic differentiation index(Fst) was 0.15300–0.78658 and the gene flow(Nm) was 0.24118–0.62035, showing a medium-high genetic differentiation status among populations. Phylogenetic analysis revealed that the Hezhou population was most closely related to the Jianghua population. Given their close geographical proximity in Guangxi and Hunan, the Hezhou and Huazhou populations can be considered part of the same population unit. The Taibei group exhibited the smallest differences in He and Ho, indicating a high degree of genetic purity. Conversely,both the Hezhou and Huazhou groups displayed lower Ho than He and substantial differences. Furthermore, the seven populations exhibited high genetic differentiation from each other, with the Taipei group showing extreme differentiation, likely due to the strait’s isolation effect. This study elucidated the genetic background and relationships among wild C. maculata populations across various regions, and serves as a valuable reference for the strategic utilization of spotted snakehead germplasm resources and genetic breeding endeavors. Particular emphasis should be placed on introducing new lineages in future breeding efforts to enhance genetic diversity within C. maculata populations and facilitate the rational exploitation of C. maculata germplasm resources.更多还原