Abstract:
Thirty-five
Pinus elliottii×
P.caribaea Morelet var.
hondurensis clones were used as experimental materials, and correlation analysis, cluster analysis and principal component analysis were performed on eight phenotypic traits to explore genetic diversity level. The level of genetic diversity was discussed to provide scientific basis for the utilization of
P.elliottii×
P.caribaea Morelet var.
hondurensis clones and breeding of improved varieties. The results showed that: (1)The coefficient of variation of growth traits ranged from 12.31%-29.28%, the mean value was 22.90%, and the diversity index ranged from 1.61-1.80 with an average of 1.69. The coefficient of variation of shape traits was between 13.34% and 47.25%, the mean value was 26.86, and the diversity index was between 1.50 and 1.94, with a mean value of 1.77. The
P.elliottii×P.caribaea Morelet var.
hondurensis clones was rich in genetic variation and high in genetic diversity. (2)Among the eight pairs of phenotypic traits, eleven pairs of trait correlations were extremely positively significant, and five pairs of them were positively significant. The selected volume was the main index for breeding selection of the material, followed by tree height. (3)When the Euclidean distance was 12, thirty-five clones were divided into six groups, and some of them come from the same source or the same male parent. (4)Three principal components were extracted from the principal component analysis of eight phenotypic traits, and the cumulative contribution rate reached 86.00%, which mainly represented six traits, so as to express the comprehensive variation of all the tested materials.