Decay fungi in decomposing post-harvest Pinus radiata root and branch debris

摘要

Knowledge of fungal populations decomposing Pinus radiata debris following harvesting may reveal a basidiomycete able to compete with pathogenic Armillaria species or help explain variation in decomposition rates. Decay fungi were isolated after 2 or3 years from buried root segments and branch segments placed on the soil surface at six sites in New Zealand. A large variety of decay fungi was obtained, different species being isolated at each site, as well as from branch versus root segments. Communities of decay fungi were more diverse in branches (one species per 1.01 segments) than root debris (one species per 5.53 segments). At the same site species tended to differ between spatially separated replicates for branch but not root segments. For root segments, identical fungi were frequently obtained at different depths in the same replicate. This implies that branch segments were colonised separately by air-borne spores, whereas root segments were exposed to mycelial growth through the soil. Few fungi were identified, but three, Resinicium bicolor, Sistotrema sp. and Stereum sanguinolentum, are common in P. radiata woody debris.