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为了探究中国东南沿海海岸线经济开发、海水污染等对该区域生物遗传多样性的潜在影响,本文使用COI基因作为DNA条形码,对从中国东南沿海广东汕头、福建东山、福建云霄、福建泉州、福建霞浦、上海崇明6个地点采集的大弹涂鱼(Boleophthalmus pectinirostris)、弹涂鱼(Periophthalmus modestus)和青弹涂鱼(Scartelaos histophorus)进行种间和种内的遗传学分析。遗传多样性分析显示,青弹涂鱼的核苷酸多样性(0.0018)在3个种中最低;青弹涂鱼广东汕头种群的核苷酸多样性(0.0018)比福建云霄种群低;大弹涂鱼的上海崇明种群核苷酸多样性(0.0021)低于其他5个地理种群。物种水平分析表明,3个物种间分化明显,种间与种内遗传距离有明显差异;不同种的单倍型在系统发育树上聚成3个高度支持的独立分支。种群水平分析显示,大弹涂鱼的6个不同地理种群之间有共享单倍型,地理种群间与地理种群内的遗传距离重叠;各地理种群之间的基因流较频繁(Nm>4);青弹涂鱼的分析情况与大弹涂鱼基本一致。大弹涂鱼和青弹涂鱼的单倍型在系统发育树上均呈现多系或并系分布格局,并未按地理位置分成不同的单系群。本研究表明,应及时加强3种鱼类及其野生种群遗传多样性的保护,且COI基因对种一级的识别明确可靠,而在地理种群水平的识别则比较困难,有待进一步深入研究。
In order to explore the potential impacts of economic development and seawater pollution on biological genetic diversity in the southeastern coast of China, COI gene was used as a DNA barcode to analyze the genetic diversity of the region from Shantou, Guangdong, Dongshan, Fujian, Yunxiao, Quanzhou, Fujian Xiapu , Boleophthalmus pectinirostris, Periophthalmus modestus and Scartelaos histophorus collected from 6 sites in Chongming, Shanghai. Genetic diversity analysis showed that the nucleotide diversity of the fish (0. 0018) was the lowest among the 3 species. The nucleotide diversity of Shanyou Turtle (0.0018) was lower than that of Yunxiao Fujian, Nucleotide diversity (0.0021) was lower than the other five geographic populations. Species level analysis showed that there was significant differentiation among the three species, and the genetic distance between species was significantly different. The haplotypes of different species clustered into three highly independent branches on the phylogenetic tree. The analysis of population level showed that the haplotypes shared by six geographical populations of M. distachyphus, the genetic distances between geographical populations and geographical populations overlapped, and the gene flow between geographical populations was more frequent (Nm> 4). The analysis of the bouncy fish is basically the same as that of the bouncy fish. The haplotypes of big-billed fish and blue-billed fish showed phylogenetic tree with multiple or parallel distribution patterns, which were not divided into different single-line groups according to geographical location. This study shows that the protection of genetic diversity of three species of fish and their wild populations should be promptly strengthened, and the COI gene identification at the species level is clear and reliable. However, it is difficult to identify the level of geographic populations for further study.