**2.4 Data analysis**

The data were submitted to normality [25] and homogeneity tests of residual variances [26]. The effect of genetic variation between clones was evaluated for all the quantified wood variables by univariate analysis of variance (ANOVA). The averages were compared by the Tukey test (α = 0.05) when the effect of clones was significant, except the morphological ratios which were descriptively analyzed. The kraft pulping properties were evaluated using linear and polynomial regression models [27], where Y represents the kappa number, yield or consumed alkali, and Xi the alkali charge used. Pearson's correlations were used to examine expected relationships between wood properties. A principal component analysis (PCA) was also performed to recognize the most important parameters for the studied clones and their relationships. The analysis was performed using a correlation matrix with 95% statistical significance. The 95% ellipse limits were also used to test the variables in relation to the clones [28].
