Study on Frequency Distribution of Phenotype Characteristics and Diversity of Picea asperata Natural Populations

The frequency distribution diagram was drawn according to the statistical frequency of the grouped property value to study the phenotype diversity of the natural populations of Picea asperata, and the distribution traits of characteristics frequency at frequency level. The phenotypic diversity degree and Shannon information index of phenotype were calculated with frequency data. Then 10 of the studied populations were clustered by means of multiple comparison and principal component analysis. The frequency distribution analysis showed that the data of phenotypic characteristics of the P. asperata population was generally accordant with normal distribution. According to the value of phenotypic diversity degree (DP) and Shannon information index of phenotype (IP), the diversity of the 10 populations was decreasingly ordered from Aba to Zhuoni, Linpo, Tiebu, Rewugou, Heishui, Baxi, Chuanpan, Dalu and Xiaojin. On the basis of multiple comparison and PCA analysis, the ten populations could be clustered into three groups. The first group included Xiaojin and Rewugou populations with low phenotypic frequency diversity but higher property value, which located in the south areas. The second group included 7 populations characterized with high to medium phenotypic frequency diversity and low to medium property value, which located in the middle and north P. asperata distribution areas. The third group had only one population, i.e., Aba population with the highest in phenotypic frequency diversity and low property value, which located in the middle area of P. asperata distribution. The study showed that there was an significant correlation between DP and IP values.