甘蓝型油菜品种的聚类分析

本研究以品种主成分值间的欧氏距离作聚类统计量,用系统聚类分析中的最长距离法和离差平方和法对来自世界7国的50个甘蓝型油菜品种进行了聚类分析。结果表明:50个品种可明显地分为6个大类,一些大类可以进一步地划分为若干亚类。品种间的遗传差异与其地理起源有密切的关系,来自同一地区的品种一般被聚在同一类中。具有相同血缘的品种也被聚在同一类中。不同的聚类方法和不同的聚类统计量其聚类结果非常一致,符合率达94%。本文还证明了表型水平主成分值之间的欧氏距离等于基因型水平主成分值之间的欧氏距离与观测值之间的欧氏距离。

Cluster Analyses of Rapeseed (Brassica napus L) Cultivars

Cluster analyses for 50 rapeseed (Brassica napus L)cultivars,which came from seven countries in the world,were made by the single linkage method and Ward's method in hierachical clustering analysis,based on the Euclldic distances between the principal component values of any two cultivars.It was showed that the 50 cultivars under the study were grouped into 6 dusters and some clusters could be further divided into several sub-clusters.The genetic divergence between the cultivars was closely related to their gengraphical distribution and the cultivars from the same region or those with certain relationship in genetics were usually grouped into the same cluster.The clustering results by different methods or different statistics were very agreeable.It was mathematically proved that the Euclidic distance between all principal component values of any genotypes under phenotypic level was equal to that under genotypic level and that between the corresponding standardized observed values.