A Uzunovic, Dian-Qing Yang, P Gagné, C Breuil, L Bernier, A Byrne
The Canadian forest products industry suffers considerable losses in revenue due to fungal stains. There is an increased awareness that more complete knowledge about the causal organisms might help solve the problem. A first step was to initiate a thorough survey of bluestain fungi in Canada. Systematic sampling was done at seven selected sawmills in six Canadian provinces. In summer 1997 fresh logs and lumber were set aside a month prior to sampling for fungi. Five commercially important softwoods, Abies balsamea, Picea mariana, P. glauca, Pinus contorta and P. banksiana were included in the studies. The objectives were to identify the main discoloring fungi and subsequently to evaluate the genetic diversity among isolates of the fungal species found to predominate. Fungi isolated from the experimental timber were identified based on their morphological characteristics, measurement of their growth rates, and by testing their mating compatibility with known mating types. A substantial number of isolates and a variety of species were obtained. Most frequently isolated were species from the genus Ophiostoma. A more diverse range of fungi was found in logs than on lumber. Preliminary data suggest that some species tend to predominate on certain wood species and in certain geographic regions but none appeared to be exclusive.