中国秀丽白虾不同地理群体的形态变异(英文)

Morphological Variation of Different Chinese Geographic Populations of White Shrimp(Exopalaemon modestus Heller)

分别测量了300尾采自中国五个淡水湖（太湖、滇池、呼伦湖、兴凯湖和巢湖）秀丽白虾的10个形态学指标，运用三种多元统计方法对不同地理群体间的形态差异进行了比较研究．聚类分析结果表明，太湖群体和滇池群体的形态最为接近，而与兴凯湖群体、呼伦湖群体和巢湖群体的趋异程度逐渐增加．判别分析按雌、雄个体分别建立了5个群体的判别函数，其中雌体的判别准确率为80．0％～93．5％（P1），87．5％～93．5％（P2），综合判别率为90．8G；雄体的判别准确率为：80．0％～90．3％（P1），77．1％～95．2％（P2），综合判别率为87．8％．五个地理群体间的形态差异须有多项参数综合判别才能辨识．主成份分析构建的三个雌体主成份的累积贡献率为75．97％，而三个雄体主成份的累积贡献率为73．63％，五个地理群体间的形态差异主要取决于全长、尾肢长、头胸甲宽、腹部长和腹部宽等5个形态学特征．提示秀丽白虾的形态变异与其生活的水体理化因子和底质不同密切相关，推测环境因子对白虾形态特征的选择作用，使其群体表型具有可塑性，此外，不当的引种和人工养殖对滇池群体种质混杂的不良影响，需要进一步深入研究，并在选种过程中加以重视．

Morphological data of white shrimp （Exopalaemon modestus Heller） collected from five fresh water lakes in China were analyzed. Ten morphometric traits were measured from over 300 shrimps and the degree of morphological similarity among sites was calculated using multivariate analysis techniques. Eight from the eleven adjusted morphometric traits in females as well as six in males were effective to discriminate differences among five populations. Discriminant analysis revealed that over 90.8 % females and 87.8 % males of individuals could be classified to their sites of origin. The results of cluster analysis and principal component analysis revealed that populations from Taihu Lake and Dianchi Lake are most similar and form a common cluster when the other three populations from Xingkai Lake, Hulun Lake and Chaohu Lake form another branch, which means that the patterns of morphological variability in this species could be determined by the local environmental conditions ,more research work must be done to identify the source of inter-population variability in the morphology of the white shrimp.