Decay resitance of Togolese teak (Tectona grandis L.f) heartwood and relationship with colour

Togolese teak (Tectona grandis L.f) is highly resistant to pathogen attack, but variability in natural durability exists between trees of different ages, plantations and geographical zones. Therefore, further information concerning this parameter of wood quality is necessary; however, traditional testing methods are difficult and time-consuming to carry out. We tested the possibility of using colorimetry to determine durability in heartwood samples taken from a wide range of trees. Twelve hundred samples from 31 trees were exposed to four fungi: Pycnoporus sanguineus, Antrodia sp., Gloephylum trabeum, and Coriolus versicolor. Wood samples were grouped into three classes (inner, intermediate and outer heartwood). The colour parameters of each sample were then determined using the CIELAB (L*, a*, b*) system and results correlated with the %mass loss of wood after fungal attack. Tests showed that Antrodia sp. and C. versicolor resulted in