陕西银杏主要栽培品种的数量分类研究

以36个陕西银杏主要栽培品种作为分类运算单位，选用20个形态性状进行聚类分析和主成分分析。结果表明,数量分类能基本反映银杏品种间的遗传差异,与传统分类法基本吻合。Q型聚类可按照植株形态特征将36个品种分为5类，其中第1类（马铃3号、泰山3号）可作优良的叶用银杏栽培品种，第4类（陕引15号）和第3类（陕引10号、C9468、陕引2号）适合做观赏绿化用；主成分分析可将原20个性状综合成7个主成分，其累积贡献率可以达到85%以上，其中叶大小（包括叶长、叶宽、叶面积）、叶形态（包括叶形指数、叶色、叶重、叶厚）为第一、二主成分，将叶形态和叶大小作为银杏品种分类的主要分类标准是可行的。

Studies on Numeric Taxonomy of Main Cultivars of Ginkgo biloba in Shaanxi Province

This paper presented cluster analysis and PCA of 20 charaters in 36 main cultivars of Ginkgo biloba in Shaanxi Province.The principal component analysis showed that the numeric taxonomy basically revealed the heritable differences among the varieties,which was the same as traditional analysis and tallies with actual situation.Q cluster analysis revealed that 36 main cultivars were classified into 5 groups based on the characteristics of plant.The 1~(st) group(Maling-3,Taishan-3)can be planted as eminent leaf-used Ginkgo biloba variety.The 4~(th)(Shanyin-15) and 3~(rd)(Shanyin-10,C94-68,Shanyin-2) can be planted as eminent ornamental-ones.20 characters were integrated into 7 principal components and their accumulative contribution rates came up to 85%.The size of leaves(including leaf-length,width and area) and the characteristics of leaves(including index of leaf-length,color,weight and thickness) were the first and second principal components.The size and the characteristics of leaves can be used as main criteria for classification.