Biodeteriorating agents associated with three tropical timber species

Abstract

Biodeteriorating agents are major problems of wood particularly in tropical Africa. Biodeterioration is widely observed in light coloured hardwood species especially Celtis mildbraedii, Ceiba pentandra and Pterygota macrocarpa. To determine biodeteriorating agents associated with these degradable woods, logs of C. mildbraedii, C. pentandra and P. macrocarpa were left for 6 weeks at the loading bay during the dry and wet seasons of the year 2001. The surfaces of logs were assessed for stain and mould after 7, 14, 28, and 42 days of storage. Pterygota macrocarpa harboured the highest fungal population count of 60.3×103 colony-forming units (CFU) with C. mildbraedii harbouring the least at 4.2×10 2 CFU after a week exposure in the dry season. Fusarium solani and Penicillium citrinum were the dominant surface moulds on log ends of wood samples, while Lasiodiplodia theobromae and Ceratocystis fagacearum were the dominant sapstain fungi. Pterygota macrocarpa and C. pentandra were more susceptible to woodborers than C. mildbraedii because of the lack of true heartwood and richer store of nutrients in its wood cells.