Early genetic evaluation of morphology and some wood properties of Tectona grandis L. clones

An early genetic evaluation of morphology and wood properties of Tectona grandis L. (teak) used two 4-yr-old trials with 36 clones x 3 blocks x 1 ramet (216 trees). Morphologic traits (breast height (DBH), heartwood (HWP), tree height) and some easily measured wood properties (specify gravity, tangential, radial and volumetric shrinkage; growth strain, and dynamic elastic modulus measured in standing tree, in logs, in green lumber and in dried lumber) were evaluated to establish clonal variations and their heritabilities. The broadsense heritability (Ĥ²) is greater than 0.3 for DBH, radial and volume shrinkage, growth strain and dynamic elastic modulus of standing trees and logs. DBH and tree height were not genetically correlated with any wood properties, although DBH was genetically correlated with tree height and the dynamic elastic modulus in dried-lumber. According with above results, the evaluation of heritability and genetic control of wood properties is limited when it is evaluated in the juvenile stage of T. grandis clones. However morphology (DBH and tree height), and two wood properties (radial and tangential shrinkage) and the dynamic elastic modulus of dried-lumber present opportunities in the heritability or genetic control values in juvenile and they can be introduced in the genetic program.