红花香椿家系生长和心材性状早晚相关性及早期选择年龄确定OA

[Objective]Taking the progeny test forest of Toona rubriflora as the research object,the correlation between growth and wood property traits at different ages was measured and analyzed to determine the optimal early selection age for T.rubriflora.[Method]Taking 59 half-sibling families of T.rubriflora as the experimental materials,the growth traits such as tree height,diameter at breast height,height to the first b ranch,and crown width at 3,6,7,11 and 15 a,as well as the wood properties such as heartwood ratio and heartwood volume were measured.On this basis,correlation analysis was conducted using R language to explore the correlations among various traits,and principal component analysis was performed to reduce the dimensions of multiple traits for a comprehensive evaluation of the growth and wood property performance of the trees.[Result]As the age of T.rubriflora increases,the Pearson correlation coefficients among most traits showed an upward trend year by year,indicating that the trait synergy strengthens with age.The tree height and diameter at breast height of 6 a trees were highly significantly positively correlated with the tree height,diameter at breast height,volume and heartwood volume of 15 a trees(P＜0.01),but the correlation coefficients of 7 a traits with the 15 a traits were generally higher than the corresponding values of 6 a traits.Principal component analysis showed that the contribution rates of tree height(H7)and diameter at breast height(D7)to the first two principal components(PC1 and PC2)at 7 a were higher than those at 6 a.The evaluation of early selection efficiency indicated that when tree height and diameter at breast height were used as selection indicators,the selection efficiency of 7 a trees for volume and heartwood volume was high,reaching 1.29,1.34 and 1.34,1.36 respectively.[Conclusion]7 a is the best age for early selection of T.rubriflora.By using tree height and diameter at breast height as selection indicators,it can effectively predict adult performance,improve selection efficiency,shorten the breeding cycle,and provide important support for the genetic improvement of T.rubriflora.