NATURAL DURABILITY OF TIMBERS TO BROWN ROT FUNGUS [GLOEOPHYLLUM SEPIARIUM (FR) KARST]

Abstract

Test of natural durability of 35 species of timbers was carried out by using agar-block method and soil-block method. The tested blocks used were taken from heartwood with the size of 2 x 2 x 1 cm³. The blocks were infected by brown rot fungus Gloeophyllum sepiarium (Fr) Karst and incubated for 4 months under room temperature condition. It was observed that the decayed wood became darkened in the incipient stage of attack. In a later stage the wood became a darker brown, decreased in weight and splited up into rectangular pieces by cracking along and across the grain. When the decaying process continued, the wood became more brittle and crack easily. The weight loss of wood tested by soil-block method was more than that tested by agar-block method. The most durable tested blocks from these two methods were found to be Anogeissus acuminata Wall, Artocarpus lakoocha Roxb, Dipterocarpus obtusifolius Teijsm, Shorea foxworthyi Sym, S. sericeiflora. Fisch & Hutch, Syzygium cumini Skeels and Terminalia mucronata Craib & Hutch.