基于5.8S rDNA-ITS序列的我国浙江沿海铜藻群体遗传多样性分析

Genetic Analysis Based on 5.8S rDNA-ITS Sequence of Sargassum horneri (Turner) C. Agardh in the Coastal Areas of Zhejiang Province,China

为了调查我国浙江沿海铜藻(Sargassum horneri)群体遗传多样性,对浙江省南麂岛火焜岙、洞头岛、枸杞岛的野生群体和南麂岛马祖岙养殖群体的铜藻44个样品的5.8S rDNA-ITS序列进行了PCR扩增和序列分析,获得DNA片段长度为1485 bp,包括部分ITS1、完整的5.8S rDNA和部分ITS2序列。序列分析表明仅有1个变异位点,说明群体间没有明显的遗传分化,遗传多样性较低。另外,将包含这一变异位点的基因型与GenBank公共数据库中另外2株铜藻的5.8S rDNA-ITS区序列进行比对,共有31个变异位点,其中插入/缺失位点10个。因此,建议加快人工铜藻场的建设以及野生铜藻场的恢复,保持铜藻场的生态平衡。

The purpose was to investigate genetic diversity of Sargassum horneri populations in the coastal areas of Zhejiang Province, China. The 5.8S rDNA-ITS sequences from 44 individuals of S. horneri were amplified by PCR and analyzed, including wild populations from Huokun＇ao of Nanji Island, Dongtou Island and Gouqi Island and Mazuao cultured population from Nanji Island in Zhejiang Province. The whole-length of sequence from all individuals was 1485 bp, including partial ITS1, ITS2 sequences, and complete 5.8S rDNA sequence. Among them, there was only one variable nucleotide site. It was suggested that there was no distinct genetic differentiation among populations with relatively low genetic diversity. In addition, 5.8S rDNA-ITS sequences from two haplotypes with the only one variable nucleotide site and another two sequences from GenBank public database were aligned, 31 variable nucleotide sites were detected, and 10 of them were insert or delete sites. Therefore, it was proposed to speed up the construction of artificial S. horneri field and restore wild S. horneri field in order to maintain an ecological balance.