Comprehensive Evaluation And Multi-character Selection Of Acacia Auriculiformis Clones

Fast-growing tree species play an extremely important role in the distribution of forestry industry in China,and eucalyptus,as an excellent short-period industrial raw material species,has an outstanding contribution to the wood production in China.However,due to the decline of soil fertility and the emergence of diseases and insect pests in some areas,Acacia auriculiformis has the characteristics of fast growth and N fixation,so as to screen the fine clones of Acacia auriculiformis as one of the tree species for eucalyptus rotation.It is of great significance.In this study,the tree height,DBH,volume,crown width,branch height and stem shape of 28 clones(1a,4a,14 a)were analyzed by means of yearsundefined follow-up investigation on the determined stand of Acacia auriculiformis in Zhongxi state-owned forest farms in Zhangzhou,Fujian Province.The results showed that:the variation coefficients of tree height,DBH and volume of 1 year old,4 year old,14 year old were decreased first and then increased.The coefficient of variation of crown width,branch height and dry form was 28.32%,56.63%and 29.68%,which was higher than that of tree height and DBH at 14 years,indicating that the differentiation of stand quality was more serious than that of growth character.The results of multiple comparison showed that there was no significant difference among 28 clones.Among them,the DBH and volume of clones No.21 and No.13 were relatively large,the height of clones 19,13,26 was relatively larger,and the height of clones No.11,No.26 and No.27 was relatively large.The crown width of the clone 26 was the smallest and the stem shape of the clone 13 was the best.The correlation analysis between characters of Acacia auriculiformis.was carried out.The results showed that the volume was significantly positively correlated with tree height and DBH,and the height of tree was significantly positively correlated with the height under branch in the trait correlation analysis.There was a significant positive correlation with stem shape,and a significant negative correlation between shoot height and crown width.In addition,in the annual correlation analysis,there was a significant positive correlation between the DBH and the height,DBH and volume of the 14 year old Acacia auriculiformis clones,and the 14 year old volume was significantly positively correlated with the 4 year old tree height and the volume of the 14 year old Acacia auriculiformis clones,and there was a significant positive correlation between the 14 year old volume and the 4 year old tree height and volume.There was a significant negative correlation between the tree height and the tree height in 14 years old.Finally,28 clones were classified and evaluated by standard deviation selection method,independent elimination method,comprehensive score method and principal component genetic distance method.The clones No.10,No.13,No.16,No.19 and No.29 were selected as excellent clones.The five clones were higher than the average tree,diameter at breast height,volume,height under branch and stem shape of 8.95%、3.97%、15.46%、18.68%、12.05%.