Résumé
Togo implements a policy of intensive teak (Tectona grandis) plantations to supplement the supply of wood products from natural forests.. These plantations are the most important because of the breadth of areas planted and of the exceptional quality of teak wood. The main objective of our study is to better understand the relationship between stand management and wood quality for different teak origins. For this purpose, a non-destructive approach is proposed based on architectural analyses in order to find indicators, of the variability of wood physical properties. This method was tested on teak plantations located in South-East Togo in the village of Agbavé (0045->6°43.J. Four plots of initial density 2500 stems/ha and tree age between 10 and 11 years were chosen in order to investigate the effect of thinning for two different oteak populations. The first provenance was introduced in Togo during the beginning of the last century. The second comes from Tanzania via Benin Republic and was introduced in Togo some years ago.. The links between developmental stages (provided by an architectural analysis) and the radial variability of wood specific density were investigated on 20 trees sampled on each studied plot (80 trees in total). The architectural analysis is a global, multileve1 and dynamic approach to plant development and allows to identify the endogenous processes of growth and to separate them from the plasticity of their expression resulting from external constraints (Barthelemy and Caraglio 2007). The analysis of radial growth was achieved on 5cm thick slice samples taken from the studied trees and located on the 1st, 2nd and 4th growth units of the trunk. The study of the variability of wood radial properties, in particular the specific density, was carried out by direct and indirect measures using the near infrared spectrometry (Bertrand and Dufour 2000). First results show how the expression .of morphological events (e.g. branching, flowering,Jorking, etc..) is related to the radial variation of wood properties and how these links are impacted by sylvicultural practices. These correlations will be used to implement a model of wood quality in a structural-functional tree model. (Résumé d'auteur)