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测量了326尾采自鄱阳湖、洞庭湖、太湖、巢湖和洪泽湖5个地理种群的秀丽白虾的8个形态学特征,经过校正后形成10个形态学比例参数。运用3种多元统计方法对不同地理种群间的形态差异进行了比较研究。主成分分析构建的前3个主成分的方差贡献率依次为31.216%、21.577%、15.239%,累积贡献率为68.032%,主成分分析结果表明5个地理种群间的形态差异主要取决于腹部宽/体长、腹部宽/腹部长和头胸甲宽/体长3个形态学特征;聚类分析结果表明,太湖种群最先和鄱阳湖种群聚成一类,随后与巢湖种群、洪泽湖种群聚集,最后才和洞庭湖种群聚集,说明太湖种群和鄱阳湖种群形态差异最小而和洞庭湖种群形态差异最大;建立了5个种群的判别函数,判别准确率为76.7%～96.7%,综合判别率为80.7%。计算了差异系数,根据Mayr等提出的75%规则,认为不同地理种群间的形态差异还没有上升到亚种水平的差异。推测遗传差异和环境因子是不同种群秀丽白虾产生形态变异的主要原因。
Eight morphological traits of 326 white shrimps collected from five geographical populations of Poyang Lake, Dongting Lake, Taihu Lake, Chaohu Lake and Hongze Lake were measured and 10 morphological parameters were calibrated. Three kinds of multivariate statistical methods were used to compare morphological differences among different geographic populations. The variance contribution rates of the first three principal components constructed by principal component analysis were 31.216%, 21.577% and 15.239% respectively, and the cumulative contribution rate was 68.032%. The principal component analysis showed that the morphological differences among the five geographical populations mainly depend on the width of the abdomen / Body length, abdomen width / abdomen length and head and thorax width / body length. The results of cluster analysis showed that the population of Taihu Lake was the first to be clustered with the Poyang Lake population, and then clustered with the population of Chaohu Lake, Hongze Lake And finally gathered with the population of Dongting Lake, indicating that the populations of Taihu Lake and Poyang Lake had the smallest differences in population morphology and the largest differences in population morphology of Dongting Lake. The discriminant functions of five populations were established with the discrimination accuracy of 76.7% -96.7% The rate is 80.7%. According to the 75% rule proposed by Mayr et al., It is considered that the morphological differences among different geographic populations have not yet risen to the level of subspecies. It is speculated that genetic differences and environmental factors are the main reasons for the morphological variation of white shrimp in different populations.