中文摘要：

为了解千岛湖大眼华鳊不同地方群体的遗传分化,以千岛湖大眼华鳊为材料,通过形态度量学和分子生物学的方法对其进行了研究。形态变量的主成分分析（PCA）结果的散布图显示,3个群体的标本重叠在一起,表明3个水域的大眼华鳊没有发生形态上的分化。通过对线粒体D-loop区的序列分析共发现了27个变异位点,35个单倍型。NJ树和单倍型网络图均未显示出各群体有分化的趋势。3个群体的平均碱基组成差异很小,且A＋T含量（64.82%）高于G＋C含量（35.18%）,各群体均表现出高单倍型多样性（h）和低核苷酸多样性（π）的特点,汾口的遗传多样性最高（h=0.968±0.018,π=0.004 76±0.000 49）,临岐次之（h=0.968±0.017,π=0.004 53±0.000 41）,富文最低（h=0.937±0.037,π=0.003 30±0.000 35）。各群体间均具有较强的基因流（Nm〉4）,其中汾口和富文之间最强（Nm=27.40）。两两群体之间的遗传分化指数（Fst）都呈现出不显著的轻度分化（Fst〈0.05,P〉0.05）。主成分分析和线粒体序列分析综合表明,千岛湖各水域的大眼华鳊属于一个随机交配群体。为了保护这一重要的渔业资源,建议继续保持千岛湖大眼华鳊的基因流格局,减少人为因素对该物种在库区活动的影响。

英文摘要：

Morphological and genetic differences of three Sinibrama macrops populations from Qiandaohu Lake were compared by traditional morphological method and mitochondrial D-loop region sequence analysis. Based on the results of principal component analysis, specimens clustered together by scatter plots of scores could not be divided. It indicated that there is no morphological differentiation among all samples from Qiandaohu Lake. 27 polymorphic sites were detected yielding 72 haplotypes. NJ tree and network showed that the geographic distribution was ambiguous. There were similar base composition among the three populations,and the content of A ＋ T （64.82%）was higher than the content of G ＋ C （35. 18% ）. High genetic variation （h）and low nucleotide diversity （π）were found in the three populations analyzed for D-loop, and the diversity of Fenkou （ h = 0. 968 ± 0.018,7r = 0. 004 76 ± 0. 000 49 ） was the highest, Linqi （ h = 0.968 ±0. 017,π=0. 004 53 ±0. 000 41） was the second,Fuwen（h =0. 937 ±0. 037,π=0. 003 30 ± 0. 000 35 ） was the lowest. The values of genetic differentiation index （ Fst ） were lower than 0.05 and not significant（P 〉 0.05 ）. A strong gene flow among the populations was observed （ Nm 〉 4 ）, and the Nm between Fenkou and Fuwen was highest （Nm = 27. 40 ）. The results showed that the three geographical populations belong to a randomly mating population. Consequently, we suggest keeping the pattern of gene flow of S. macrops,and reducing the influence of human activities so as to protect this important species in fishery resources.