MORPHOLOGICAL VARIATIONS ANALYSIS AMONG POPULATIONS OF HYRIOPSIS CUMINGII IN FIVE LARGE LAKES OF CHINA

Based on 10 morphological proportional characters of Hyriopsis cumingii,three multivariation analysis methods (cluster analysis,principal component analysis and discriminant analysis) were used to comparably investigate the morphological variations among the region populations of five large lakes in China (Poyang Lake,Dongting Lake, TaiLake,Cao Lake,Hongze Lake) and cultured population in Zhuji.The results of cluster analysis and principal component analysis indicated that the morphological characters were similar between the populations of Taihu and Chao Lake,but quite different from that of Hongze Lake.In the principal component analysis,three principal components were constructed,the contributory ratio of the first principal component was 27.87%,the second principal component was 14.26%,and the third principal component was 11.91%,the cumulative contributory ratio was 54.04%.The result of discriminant analysis revealed that there were significant differences among the five populations and cultured population (P 0.01).The identification accuracy was 76.67%—88.57% (P 1) and 70.56%—100% (P 2),among the five populations and cultured population,the identification accuracy of P 1 ranked as Chao (88.57%)Tai (85.71%)Hongze (80.56%)Poyang(80%)Dongting (77.41%)Zhuji (76.67%),the identification accuracy of P 2 ranked as Dongting (100%)Hongze (96.67%)Zhuji (88.46%)Poyang (80%)Chao (73.81%)Tai (70.56% ).The discriminant functions of the five populations and cultured population were established,and the discriminant accuracy was 73.33%— 86.67% (P 1) and 72.73%—100% (P 2),the identification accuracy of P 1 ranked as Poyang (86.67%)Hongze (83.33%)Tai (80.00%)Dongting (76.67%)Chao (75.00%)Zhuji (73.33%),the identification accuracy of P 2 ranked as Chao (100%) = Hongze (100%)Dongting (92.00%)Zhuji (91.67%)Poyang (78.79%)Tai (72.73%).The total discriminant accuracy was 83.33%.