基于线粒体D-loop基因的珠江翘嘴鲌遗传多样性与遗传分化研究  

Genetic diversity and genetic differentiation of Culter alburnus from eleven geographical populations of the Pearl River based on mitochondrial D-loop gene

作　　者：杨子拓 孙际佳[1,2] 李桂峰[3] 肖诗斌[1,2] 张鹤千 杨慧荣[1,2] 赵会宏[1,2] 刘丽[1,2] 

机构地区：[1]华南农业大学动物科学学院,广东广州510642 [2]华南农业大学动物科学学院∥广东省农业动物基因组学与分子育种重点实验室,广东广州510642 [3]中山大学生命科学学院,广东广州510275

出　　处：《中山大学学报（自然科学版）》2016年第2期89-96,共8页Acta Scientiarum Naturalium Universitatis Sunyatseni

基　　金：公益性行业(农业)科研专项资助项目(201303048);国家科技基础条件平台建设项目(2008DKA30470-010)

摘　　要：为探明分布于珠江流域的野生翘嘴鲌种群遗传多样性与遗传分化状况,实验在珠江流域广东省(肇庆和韶关)、广西省(梧州、昭平、平乐、柳城、桂平、平果、田阳、龙州和扶绥)自然河流内采集野生翘嘴鲌种群。研究采用线粒体分子标记技术(D-loop基因)对珠江流域翘嘴鲌种群的遗传多样性做一个多方面的分析。利用PCR技术,得到D-loop全基因序列856 bp,通过分析发现,176个个体中合计41个单倍型;其单倍型多样性指数(Hd=0.875 06)和核苷酸多样性指数(π=0.007 00)显示种群具有较高的遗传多样性。11个野生地理群体翘嘴鲌遗传分化指数(FST)为0.188 28,显示珠江流域翘嘴鲌作为一个大种群已产生了中度分化,种群分化时间经计算推断为5万年前左右。其中,梧州和桂平,梧州和肇庆,昭平和平乐,田阳和平果,扶绥和大部分种群(柳城、桂平、田阳、韶关)的遗传分化程度都较低(FST<0.05),基因流Nm>5;其他种群两两之间达中度遗传分化(FST>0.05),基因流Nm<5。分子系统树和单倍型网络关系显示:单倍型Hap1和Hap2可能为单倍型先祖,其余单倍型由其进化而来。但遗传距离与地理距离并没有显著相关性,种群扩散规律需要进一步探索,说明珠江流域野生翘嘴鲌并未地理因素产生种属分化。Culter alburnus is one of the most economically important edible freshwater fish in the Pearl River and is widely distributed in the Yangtze River and the Yellow River. To assess the level of genetic diversity and genetic variation of C. alburnus populations within the Pearl River,the samples were col-lected from the eleven geographical populations from Guangxi and Guangdong Province（ Wuzhou,Zhaoping,Pingle,Liucheng,Guiping,Pingguo,Tianyang,Longzhou,Fusui）. Among the 176 D-loop sequences,there were 286 polymorphic sites,including 115 variation sites and 59 parsimony informative sites. Overall,41 haplotypes were defined among 176 Culter alburnus individuals. C. alburnus populations in the Pearl River were being a high haplotypic diversity index（ Hd= 0. 875 06） and low nucleotide diversity index（ π = 0. 007 00）. The AMOVA（ analysis of molecular variance） index of total populations was 0. 188 28,indicating that the genetic differentiation among populations was moderate. It was predicted that differentiation time was about 50 × 10^3 years. FSTindex between WZ and GP,WZ and ZQ,ZP and PL,TY and PG,especially,FS and LC,GP,TY,SG,was showed significant genetic differences（ FST 〉0. 25）. The Phylogenetic tree and the Median joining drawing showed that haplotype 1 and 2 were the ancestors of other haplotypes. The relationship between genetic distance and geographical distance should be explored in the future.

关 键 词：珠江流域 翘嘴鲌 D-LOOP 遗传多样性 遗传分化 

分 类 号：S932.4[农业科学—渔业资源]