Abstract: Based on the branches and leaves of artificial Xanthoceras sorbifolia population in Dingxi district of Gansu,5 phenotypic traits were investigated for 59 X.sorbifolia samples in trial area.Phenotypic variation was studied by using variance analysis and variation coefficient,between various individuals,different sections of branch and different branch types.The results showed that there was extremely significant difference (P＜0.01)among various phenotypic traits of leaves and there was greater variation among different individuals of X.sorbifolia in trial area,but the variation degree of various phenotypic traits was different and the sequence of variation coefficient of traits is as follows:length of leaflet(18.70%)＞ width of leaflet(17.96%)＞ length of compound leaf(17.04%)＞ pair number of leaflet(14.14%)＞ amount of leaflet(13.07%); between different sections of branch,the phenotypic traits of leaves had no obvious differences and coincident change law,and only the indicators of width of leaflet,pair number of leaflet and amount of leaflet had very significant differences(P﹤0.01); between the different branch types there was obvious differences among phenotypic traits of leaves,and had significant differences (P﹤0.05)or very significant differences(P﹤0.01)except for pair number of leaflet.Besides,the type of branch was closely correlated to the ability of resisting disease and insects of X.sorbifolia,and the individuals with velutinous scarlet branch strongly resisted diseases and insects,whereas the individuals with brown branches but no velutinous had very serious diseases and insects,these characteristics can be treated as an important indicator for preliminary selection of fine individual of X.sorbifolia.

Key words: Xanthoceras sorbifolia, branch and leaf, phenotypic traits, differentiation