| 摘要: |
| 光倒刺鲃（Spinibarbus hollandi）是华南地区重要的经济鱼类，现已成为重要的养殖鱼类之一。为了解光倒刺鲃的遗传多样性及遗传结构特征，作者对8个水系共191尾样本的线粒体细胞色素b（Cyt b）基因全序列进行了测定与分析。在所有序列中，共有51个变异位点，共检测出16个单倍型，单倍型多样性为0.761，核苷酸多样性为0.012。基于Cyt b基因全序列构建的NJ树显示，所有种群合聚为两大支，其中资江、钱塘江、郁江和柳江的全部样本以及北江、赣江和九龙江的部分样本组成了Ⅰ支，而东江水系的全部样本及北江、赣江和九龙江水系的部分样本则组成了Ⅱ支。单倍型网络图显示，东江的全部单倍型与北江及赣江的部分单倍型有着较近的亲缘关系，而与其他单倍型发生了较大的遗传分化；而九龙江种群内部不同的单倍型间亦有着较大的遗传差异；北江的部分单倍型、柳江及郁江种群的全部单倍型与资江、钱塘江的全部单倍型、赣江和九龙江的部分单倍型之间的亲缘关系亦较为密切。我们推测光倒刺鲃存在两个扩散中心：西江、北江水系扩散中心及东江水系扩散中心。其扩散路径为：西江及北江水系的种群往北向长江水系扩散，长江种群然后往钱塘江及九龙江等水系扩散；东江水系的种群扩散路径可分为3支，一支往北向长江水系扩散，一支往西向北江水系扩散，一支往东向九龙江等水系扩散。AMOVA分析表明，光倒刺鲃地理区之间变异占1.61%，地理区内种群间约占56.47%，种群内的变异占45.14%。错配分析及中性检验显示，全部种群、各个种群在历史上均没有发生过明显的扩张。本研究结果可为光倒刺鲃种质资源保护和利用提供科学依据。 |
| 关键词: 光倒刺鲃(Spinibarbus hollandi) 遗传多样性 遗传结构 细胞色素b基因 |
| DOI：10.11693/hyhz20160300064 |
| 分类号: |
| 基金项目:广东省科技计划项目，2014A020208145号。 |
附件 |
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| GENETIC DIVERSITY AND STUUCTURE OF SPINIBARBUS HOLLANDI BASED ON NUCLEOTIDE SEQUENCES OF MTDNA CYTOCHROME B GENE |
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LAN Zhao-Jun1, LI Qiang2, SHU Hu2, GU Ping-Hua1, WANG Hang-Jun1, WU Tu-Jin1
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1.Shaoguan Fisheries Research Institute, Shaoguan 512006, China;2.School of Life Science, Guangzhou University, Guangzhou 510006, China
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| Abstract: |
| Spinibarbus hollandi (Cypriniformes:Cyprinidae:Barbinae:Spinibarbus) is an economically important freshwater fish species that have been farmed increasingly.To understand its genetic diversity and structure to protect its natural resource in South China,variations in the population genetics and phylogeography were studied.191 specimens from 8 populations were collected in 8 drainage systems in South China and their nucleotide sequences of mtDNA Cytochrome b gene (1141 bp) were investigated.51 variable sites (4.47%) of the gene sequences and 16 haplotypes were identified.The haplotype diversity and nucleotide diversity are 0.761 and 0.0120,respectively.The neighbor-joining tree shows two major clades.Clade I is composed of all specimens from Zijiang River and Qiantang River and some from Beijiang River,Ganjiang River,and Jiulong River.Clade Ⅱ includes all specimens from Dongjiang River and Beijiang,Ganjiang and Jiulong Rivers.The two clades features with haplotypes in different levels of genetic variation for having experienced own evolution lines under unique geographic conditions.Four regions of genetic distribution could be defined:the Pearl River region,the Changjiang (Yangtze) River region,the Jiulong River region,and the Qiantang River region.Analysis on molecular variance (AMOVA) showed that the genetic variation of populations among different regions was 1.61%;while that of inter-population of a region was 56.47%,and that of intra-population of different regions was 45.14%.It is indicated that the genetic variation took place mainly among different populations within a region and within a population of different regions.Results of mismatch distribution and neutrality test reveal that there have been no obvious expansion in both all or individual population of S.hollandi;and they were all multimodal types.Values of Fu's Fs and Tajima's D were negative,except for the population of Yujiang River,being non-significant or positive.Therefore,the populations have been relatively stable in evolution,which shall be very informative for the conservation and sustainable exploitation for wild S.hollandi populations. |
| Key words: Spinibarbus hollandi genetic diversity genetic structure Cytochrome b gene |
