中国沿海6个花鲈群体的形态差异分析

通过聚类分析、主成分分析和判别分析等多元分析方法,对东港、绥中、秦皇岛、青岛、舟山以及珠海等6个花鲈(Lateolabrax maculatus)地理群体的8个形态比例性状进行了研究。聚类分析和主成分分析表明,6个花鲈群体可被分为两支:来自黄海、渤海海域的东港、秦皇岛、绥中和青岛群体为一支(北方群体);东海海域的舟山群体和南海海域的珠海群体为另一支(南方群体)。南北群体间有一定程度的形态分化,和舟山群体相比,珠海群体和北方群体的亲缘关系更近。主成分分析获得的3个主成分方差贡献率分别为31.726%、27.744%和14.075%,累计贡献率为73.545%。利用8个变量构建的6个地理种群的判别公式,判别准确率在63.6%~84.4%之间,综合判别准确率72.7%。本研究结果为花鲈地理种群判别、种质资源评价以及良种选育等提供了基础资料。

Morphological variations of six spotted sea bass (Lateolabrax maculatus)geographical populations along China coast

Spotted sea bass (Lateolabrax maculatus)is an eurythermic fish inhabiting in the coastal lower layers,and widely distributed along the coast of China and the Korean peninsula.Spotted sea bass is euryhalinous,and can survive in fresh water as well as marine water.With the breakthroughs in key technologies such as artificial breeding and feeds,the culture of spotted sea bass has been rapidly developed. Recent years,many Chinese researchers have studied the nutrition,reproductive physiology and population genetics of spotted sea bass.Morphology is an important character of organisms.Through the measurement of morphological data,and corresponding statistical analysis,the similarities and differences between individuals or groups can be compared.The common method for analyzing morphological differences is the multivariate statistical analysis,which contains multiple variance analysis,cluster analysis,factor analysis,principal component analysis,discriminant analysis and others.Multivariate analysis is able to analyze the statistical regularity of the multiple indexes and the objects that are related to each other.In the study of fish, multivariate analysis is widely used in the comparison of morphological differences of different geographic populations,morphological differences between hybrids and their parents,and discrimination of varieties. However,the morphological variation analysis of different geographical populations has not been reported yet. In this paper,the morphological variations of six spotted sea bass geographical populations along China coast were analyzed using multivariate analysis with eight proportional characters.Cluster analysis and principal component analysis showed that these six populations could be divided into two groups:the northern group that included Donggang,Qinhuangdao,Suizhong and Qingdao population,which were from the Yellow Sea and the Bohai Sea;the southern group that included Zhoushan (from the East China Sea)and Zhuhai population (from the South China Sea).There were a certain morphological differences between the north and the south group,while the relationship between Zhuhai and the northern population was closer than that between Zhoushan population and the northern group.Principal component analysis constructed 3 principal components with contributions of 31.726%,27.744% and 14.075%,respectively,and the cumulative contribution rate was 73.545%.Finally,discriminant formulas were constructed by 8 variables to discriminate the six geographical populations. The discriminant accuracy varied from 63.6% to 84.4%, and synthetic discriminant accuracy rate was 72.7%.The results of this study provide basic data for the identification of geographical populations,evaluation of germplasm resources as well as the selection of fine variety.