河南省小黄黝鱼群体遗传多样性

小黄黝鱼Micropercops swinhonis (Günther, 1873)]是中国特有的一种小型淡水虾虎鱼类,广泛分布于长江及以北各水系,其中在河南省各水系均有分布。为评估河南省小黄黝鱼种质资源现状及其遗传多样性,本研究对河南省境内黄河、长江、淮河和海河4个水系77尾小黄黝鱼样品进行线粒体COI基因的扩增。结果显示,河南省小黄黝鱼的平均单倍型多样性(H_d)为0.89088,平均核苷酸多样性(π)为0.00361,其中淮河水系华行村种群(HXC)核苷酸多样性最高(π=0.00433),黄河水系马颊河种群(MJH)核苷酸多样性最低(π=0.00078);系统发育树和单倍型网络图结果均显示小黄黝鱼并未按照水系形成明显的地理遗传支系;根据4个水系进行分组, AMOVA分析显示仅16.00%的变异来自于水系间,而78.43%遗传变异来自各群体内部;同样地,未预先设定分组情况的SAMOVA分析也得到了相似的结果,不支持小黄黝鱼具有明显的地理遗传结构的假设;种群历史动态分析显示,河南省小黄黝鱼种群呈逐步增长趋势; Fu’s FS中性检验与错配分析表明,河南小黄黝鱼种群可能经历过近期群体扩张事件,且该过程可能与气候变为暖湿型有关。

Genetic diversity of wild Micropercops swinhonis populations in Henan Province

Micropercops swinhonis is a specific small freshwater demersal fish, which is widely distributed in the water systems of the Yangtze River and its northern rivers, as well as the rivers of Henan Province. To assess the current situation of germplasm resources and genetic diversity, 77 M. swinhonis samples were collected from the basins of the Yellow River, Yangtze River, Huaihe River, and Haihe River in Henan Province. We analyzed the population genetic diversity and differentiation of the species using the mitochondrial COI gene. In this study, we amplified the partial mitochondrial COI gene sequences of 77 individuals from 10 populations (PH, BSH, HZH, TRQ, MJH, XLSSK, HXC, YH, QH, and WH). The results showed an average haplotype diversity of 0.89088 and average nucleotide diversity of 0.00361 in all populations, with a maximum and minimum in the HXC and NJH populations, respectively. AMOVA analysis showed that the genetic differentiation of M. swinhonis mainly occurred within the population variation, with 78.43% genetic variation within M. swinhonis populations. The results of phylogenetic tree and network of haplotypes suggested that M. swinhonis did not form from a significant geographic cluster. Similarly, the results of SAMOVA support the phylogenetic tree and network of haplotypes when not using grouping in advance. Demographic history analysis showed that the 10 populations experienced rapid population growth and have maintained an upward trend. Fu''s F_S value and mismatch nucleotide analysis revealed that a recent population expansion had occurred in M. swinhonis populations, the process for which may be related to the climate changing to warm and humid.