鄱阳湖及邻近水系银鲴的种群分化研究  

Population Differentiation of Xenocypris argentea in Poyang Lake and Adjacent Drainages

作　　者：胡玉婷[1,2,3] 杨少荣[1,2,3] 黎明政[1,2,3] 曹文宣[1,2] 刘焕章[1,2] 

机构地区：[1]中国科学院水生生物研究所,武汉430072 [2]中国科学院水生生物多样性与保护重点实验室,武汉430072 [3]中国科学院研究生院,北京100049

出　　处：《四川动物》2012年第5期696-703,共8页Sichuan Journal of Zoology

基　　金：江西省农业厅研究课题(IHB/CN2010073);国家自然科学基金委员会与财团法人李国鼎科技发展基金会联合基金(31061160185)

摘　　要：以2010～2011年采自鄱阳湖及邻近水系(赣江和洞庭湖)的7个地理种群的228例银鲴样本为研究对象,结合形态和线粒体Cytb数据,研究了银鲴种群的分化情况。主成分分析显示,银鲴地理种群间已具有一定的形态差异,尤其是赣江种群与其他种群间形态差异显著,能够明显区分。判别分析显示各地理种群间判别率较高,尤其是赣江种群高达100%。综合形态分析结果,银鲴各地理种群间形态差异明显。分子分析中,获得长度为1131bp的Cytb基因部分序列,共检测到107个单倍型。各地理种群单倍型多样性均较高(0.96471～0.99310),核苷酸多样性均较低(0.00419～0.00560)。分子变异分析(AMOVA)表明,银鲴群体的遗传变异主要发生在地理种群内,地理种群间分化程度很低,相互间存在着广泛的基因交流。结合形态和分子分析结果,认为银鲴不同地理种群间的形态差异主要是其对特定环境适应的结果,而不是遗传分化所产生的。In the present study, 228 samples of Xenocypris argentea were collected from 7 localities of Poyang Lake and its adjacent drainages （Ganjiang River and Dongting Lake） , which were analyzed through morphological and molecular methods to investigate population differentiation. The results of Principal Component Analysis showed that populations morphological differences of X. argentea, especially the samples from Ganjiang River was significantly distinguished from the others. Dis- criminatory analysis showed that the discriminant accuracy of populations were high, particularly for Ganjiang population, which was 100%. Morphological analysis indicated that there were differences among populations. The 1131 bp of mito- chondrial cytochrome b （Cyt b） gene sequences of all X. argentea individuals were used for molecular differentiation analy- sis. Among the 228 sequences, 107 haplotypes were identified with 62 parsimony informative sites detected. All the 7 popu- lations were characterized with high haplotype diversity （0. 96471 - 0. 99310） and low nucleotide diversity （0. 00419- 0. 00560）. Analysis of molecular variance （AMOVA） of the 7 populations showed that the genetic variance mainly presen- ted in individuals within populations, and there were no genetic differences among populations. Exact test also showed that the haplotype distribution had no significant difference between each pairs of populations. Therefore, based on molecular a- nalysis, the investigated populations showed extensive gene flow to each other and no genetic differences. This inconsistence between morphological and molecular results was probably ascribed to populations＇ morphological adaptations to different en- vironments in the course of growth and development.

关 键 词：银鲴 鄱阳湖 形态变异 细胞色素B 种群分化 

分 类 号：S917.4[农业科学—水产科学]