The Use Of The Pilodyn For Assessing Wood Traits Of Living Trees

Pilodyn is a kind of Non-Destructive Testing tester in the indirect estimation of wood density.It is used in the indirect estimate the wood property of live trees. The article studied the application effect of Pilodyn in important tree species in china. Tthrough the living tree of Larrix kaempfri was penetrated by pilodyn in the field,and wood basic density and fiber length and width of increment core were menstruated in door. Through the analysis of pilodyn penetration,the basic density of increment core,fiber length and fiber width,the result showed that the average of the pilodyn penetration of 95 individuals of Larrix kaempfri in south direction was 15.50 mm, which was 5.5% higher than that in north direction(14.69mm). Pilodyn penetration Pn,Ps和Pa had significant negative correlation with the outerwood density(Dao)(-0.5275～-0.5827),The correlation coefficient was higher than that between the Pn,Ps和Pa and the basic density, which was -0.4756～-0.5134. Pn,Ps和Pa had significant negative correlation with breast diameter(DBH), the correlation coefficient was -0.3523～-0.4100. The correlation coefficient between breast diameter(DBH)and pilodyn penetration in north direction was bigger than in south direction. The biggest contribution rate to the pilodyn penetration is basic density(40.4%),and Pa had significant negative correlation with both Da and Dao, the significant probability P<0.001. The Pilodyn penetration(Pa)of Larrix kaempfri had significant negative correlation with wood fiber character(later wood fiber length and later wood fiber width). The Pilodyn penetration could estimate the average of outerwood density(Dao)and fiber length and fiber width of laterwood in an entire radial direction in living tree of Larrix kaempfri , and it could also estimate the basic wood density (Da)in an entire radial direction.We selected 79 individuals for deeper research and established path diagrams between each indicator and Pilodyn according to biological principle. Besides, we shrank the model to get a new model, which can hold 85% of the information. In the new model, wood density, growth increment and late wood tracheid length respectively contributed 46.71%, 24.47% and 28.82%. The lineal equation of northbound and southbound was respectively: y = -0.0055x + 0.4374 (R2 = 0.3931)and y = -0.0041x + 0.4125(R2 = 0.209). The equation of average value was y = -0.0061x + 0.4475(R2 = 0.4253). R2 of south(0.4253) was much higher than that of south(0.209). The prediction precision of north and south was respectively 98.05% and 97.80%, with an average of 98.31%. Better correlations between Pilodyn and wood density as well as fiber characteristics could be expected in the south than in the north. Thus, it would be efficient to use Pilodyn in south area. To sum up, this research provides evidence for further study on Pilodyn use according to reveal the relationships between Pilodyn and wood density as well as fiber characteristics.Through the study of 127 individuals of Pinaceae armandii, we gained the following conclusions: Pilodyn measured value(P) had no significant differences in the north and south directions and was accordant with testing results of outer wood basic density (Do) and wood basic density (D). Pn, Ps and Pa had highly significant correlations with outer wood basic density (Dno, Dso and Dao), and the correlation coefficient was respectively -0.687,-0.772 and -0.771;Pn, Ps and Pa also had very significant correlation with wood basic density (Dn, Ds and Da), with the correlation coefficient respectively -0.546,-0.626 and -0.649;wood density contributed most in the multiple regression equation (52.86%～63.74%). The model to predict wood density through linear regression methods with Pilodyn average value was yDa = -0.0071x + 0.5172(P= 0.000,R2 = 0.4218),yDao = -0.0089x + 0.5638(P= 0.000,R2 = 0.5943). Not only could the Pilodyn measured value predict the outerwood basic density, but also it can foretell the basic wood density in an entire radial direction.Through non-destructive testing method,144 individuals of the Larrix kaempfri family living tree's wood property genetic variation was measured. Besides, wood basic density of increment core was tested indoor. Ideal results were gained through the correlation analysis between the pilodyn measured value of living tree and wood basic density of increment core. The research revealed that In the 9 Larrix kaempfri families, family 34 and family 32 respectively took the highest and lowest in pilodyn measured value (Pn), outer density (Do) and the wood basic density (Db). As to Pn, the 9 families sorted in ascending order. However, when it came to Do and Db, they sorted in descending order. Significant genetic variation of Pilodyn measured value (Pn), outer wood density (Do) and basic density (Db) existed among families. According to analysis on phenotypic correlation and genetic correlation, we concluded that Pilodyn measured value (Pn) had remarkable negative correlation with outer density (Do) as well as basic wood density (Db) of the entire wood, with the correlation coefficient respectively -0.692 ~ -0.8142 and -0.671～-0.9093. As to family and individual heritability, Pilodyn measured value (Pn) were 0.45 and 0.28, outer basic density (Do) were 0.46 and 0.33 and the entire wood were 0.44 and 0.26. Obviously, family heritabilities of the three characteristics were all greater than individual heritabilities and the three genetic parameters were close. Therefore, it was reliable and feasible to use Pilodyn measured value (Pn) to replace outer density (Do) and basic wood density (Db) to estimate the wood density genetic parameters.The Research on 166 living trees of Populus tomentosa clones showed that :When we sorted the clones by Ps, Dso and Ds, we found significant correlations among the three ranges (-0.749～-0.651), which proved reliability of sorting Populus tomentosa clones with Pilodyn by density. It was significant of correlation between Ps,Ds and Dso of the(-0.506～0.706). Significant correlation between Ps,Ds and Dso of the every clone mean Populus tomentosa(-0.840～0.808)was also found. It shows that using Pilodyn to estimate the wood density of Populus tomentosa is reasonable.The correlation between the every clone mean was higher than individuals. It showed the mean of Pilodyn penetration can estimate the variety of wood density to the same clone accurately. Variance analysis on 28 clones of the three material properties Ps,Ds and Dso homogeneously marked significant correlation. Respectively according to Ps,Ds and Dso, we divided the 28 clones into 4 groups: (A)basic density of high wood and fast growth(,B)basic density of low wood and fast growth(,C)basic density of high wood and slow growth(D)basic density of low wood and slow growth. Variance analysis and multiple comparisons proved the above method remarkably effective. Meanwhile, six clones with fast growth speed and high wood density, involving 11,12,346,191,337,24,384, were selected by phenotypic character. The article verified the effect of Pilodyn, demonstrated the feasibility and reliability of Pilodyn on testing wood density of Populus tomentosa, and laid foundation for further research on non-destructive testing and colonial selection improvement of Populus tomentosa.