Variação estrutural de clones tricompostos de Hevea brasiliensis (Willd. ex A. Juss.) Müll. Arg

Abstract

The main objective of this study was to characterize the wood anatomical structure of the rubber tree clone (PB311), under the influence of two different canopy grafts. The following rubber trees were selected in the system of double grafted system i) root from seeds + clone PB311 (panel) + clone FX2784 (canopy); and (ii) roots from seeds + clone PB311 (panel) + MDF180 clone (canopy). For each tree, disks located immediately below the insertion of the canopy clone were obtained, from which the regions corresponding to tension, opposite and normal wood, for posterior radial characterization were identified. The anatomical analyzes were conducted in accordance with the standards established by the International Association of Wood Anatomy Committee. The Kruskal-Wallis nonparametric test was applied, followed by the Bonferroni method for multiple comparisons among the types of woods and radial positions studied, both at 5% of significance. Multivariate associations were assessed among the anatomical characteristics of both double grafted rubber trees, by means of two step cluster analysis. Quantitative morphological differences were observed in the wood cells of the double grafted studied clones. The rays height and the vessels tangential diameter were the most important morphologic characteristics for the double grated trees distinction, indicating possible anatomical adaptations of PB311 clone in canopy graft. The canopy clone can modulate the quantitative anatomical characters of the panel clone, depending on the plant’s needs.