The ability of some fungi to cause decay in the East African camphor tree, Ocotea usambarensis

Of 47 fungi collected from decaying Ocotea wood, 36 exhibited phenoloxidase activity against gallic acid, 40 exhibited it against tannic acid, 33 possessed laccase and 6 possessed tyrosinase. Thus their capacity to produce ligninolytic enzymes indicated that a high proportion of these fungi could cause white rot in Ocotea wood. It was shown that all 21 fungi tested were capable of causing significant weight loss in Ocotea wood blocks in vitro. Basidiomycetes exhibited the greater capacity to cause decay when compared to non-basidiomycetes. The rank order of species in terms of proportional weight reduction in the wood blocks over four months was: Trametes versicolor (28%), Ganoderma australe (16%), Phellinus sp. 2 (15%), Phellinus senex (10%), Stereum ostreum (10%), Loweporus inflexibilis (9%), Stereum hirsutum (8%), P. gilvus (7%), and Schizophyllum commune (2%). The most aggressive non-basidiomycetes, however, were comparable to S. commune, and these were: Cylindrodendrum album (3%), Cylindrocarpon destructans (2%), Daldinia concentrica (2%) and Nodulisporium sp. (2%).