基于线粒体DNA控制区的黄姑鱼养殖群体与野生群体比较研究

Comparative Analysis of Genetic Variation Between Cultured and Wild Populations of Nibea albiflora Based on Mitochondrial DNA Control Region

黄姑鱼(Nibea albiflora)是我国重要的经济鱼类。由于受到过度捕捞和环境污染等因素的影响,野生黄姑鱼资源量急剧下降。为了解黄姑鱼野生群体与养殖群体的种质资源现状,本研究扩增了2个野生群体和2个养殖群体的线粒体DNA控制区高变区部分序列,同时结合NCBI数据库中部分已发表序列进行分析。研究显示:173个黄姑鱼个体共检测到62个单倍型,其中养殖群体仅7个;养殖群体和野生群体之间仅存在1个共享单倍型;养殖群体单倍型多样度(0.4160~0.7123)明显低于野生群体(0.9130~0.9926)。基于线粒体DNA控制区单倍型构建的网络图未发现明显的谱系结构。群体间遗传分化指数FST显示,黄姑鱼养殖群体间以及养殖群体与野生群体间产生了较大的遗传分化。AMOVA分析结果显示,群体内部遗传变异占绝大部分。黄姑鱼野生群体的历史动态分析结果暗示,其可能经历过近期群体扩张事件。综合上述结果,黄姑鱼养殖群体遗传多样性显著降低,有必要开展黄姑鱼遗传多样性监测工作,并采用科学的人工繁育方法,保护黄姑鱼的优质种质资源。

Nibea albiflora is an important economic fish in China.Due to the influence of overfishing and environmental pollution,the resources of wild Nibea albiflora decreased sharply.In order to understand the present situation of germplasm resources of wild and cultured populations of N.albiflora,protect the wild resources of N.albiflora and develop aquaculture,the partial sequences of mitochondrial DNA control region hypervariable region of 2 wild populations and 2 cultured populations were amplified and analyzed combined with some published sequences in NCBI database.The results showed that 62 haplotypes were detected in 173 individuals,of which only 7 were detected in cultured population,and there was one shared haplotype between cultured population and wild population.the haplotype diversity of cultured population(0.4160~0.7123)was significantly lower than that of wild population(0.9130~0.9926).No obvious pedigree structure was found in the network map based on the haplotype of mitochondrial DNA control region.The index of genetic differentiation among populations(FST)showed that there was a great genetic differentiation among cultured populations and between cultured and wild populations.The results of AMOVA analysis showed that the genetic variation within each population accounted for the vast majority.The results of historical dynamic analysis of the wild population of N.albiflora suggested that it may have experienced recent population expansion events.Based on the above results,the genetic diversity of N.albiflora culture population decreased significantly.Therefore,it is necessary to carry out genetic diversity monitoring and adopt scientific artificial breeding methods to protect high-quality N.albiflora germplasm resources.