Needles Phenotypic Diversity Analysis in Different Dominance Hierarchies of Pinus yunnanensis

In order to fully understand the genetic diversity of Pinus yunnanensis germplasm resources, P. yunnanensis, which has different growth stages of dominant wood, medium wood and inferior wood, was used as the research object to investigate and analyze the phenotypic traits of needles. Results show that the coefficients of variance (CV) of 7 traits are 13.28−20.74% with an average of 16.96% in the dominant trees, 14.56−20.00% with an average of 16.87% in the intermediate trees and 13.41−17.79% with an average of 15.58% in the suppressed trees, respectively. The Shannon-Wiener's diversity index of 7 traits are 1.342 4−1.427 0 with an average of 1.399 5 in the dominant trees, 1.357 1−1.432 9 with an average of 1.394 1 in the intermediate trees and 1.340 5−1.443 4 with an average of 1.412 7 in the suppressed trees, respectively. There are no significant differences for the coefficient of variance and Shannon-Wiener's diversity index based on the analysis of variance. The mean coefficient of phenotypic differentiation is low (9.85%), and the percentage of variance components between group (6.67%) is lower than the percentage of variance components within group (51.90%), indicating that the variance within group was the main source of the phenotypic variation of the species. The phenotypic diversity of needles of P. yunnanensis is less affected by the different dominance hierarchies. Taken together, the different growth dominance levels have little effect on the phenotypic diversity of P. yunnanensis .