The impacts of broadcast burning after clear-cutting on the diversity of ectomycorrhizal fungi associated with hybrid spruce seedlings in central British Columbia

Morphological and molecular (polymerase chain reaction - restriction fragme nt length polymorphism) methods were used to assess ectomycorrhiza (ECM) di versity in naturally regenerating and planted Picea engelmannii Parry ex En gelm. x Picea glauca (Moench) Voss seedlings in two recently clear-cut site s, two clear-cut and broadcast burned sites, and two mature forests (> 100 years) in central British Columbia. Based on 24 characterized ECM, burning did not affect overall diversity (Shannon, Simpson, Shannon evenness, and M argalef indices). However, the occurrence and relative abundance of some EC M morphotypes varied significantly. Hebeloma and a Russulaceae type 1 were more abundant and Cenococcum was less abundant in planted seedlings from cu t-burned sites compared with those from clear-cut sites. E-strain, MRA, and Amphinema were more abundant in planted seedlings from both cut-burned and clear-cut sites compared with naturally regenerating seedlings from mature sites. ECM diversity of regenerating seedlings was significantly greater i n mature forests compared with clear-cut sites and was greater in planted s eedlings than naturally regenerating seedlings in clear-cut sites. Molecula r analysis of the internal transcribed spacer region of the nuclear-encoded ribosomal RNA gene repeat showed no significant differences among treatmen ts or seedling type. Twenty-two genotypes were identified from eight common morphotypes: Cenococcum (one), Thelephora (two), E-strain, Tuber, Hebeloma , and Russulaceae type 1 (three each), MRA (four), and Amphinema (six). Heb eloma genotypes matched three for Amphinema; genotypes from unidentified li ghtly colonized tips matched those for E-strain, MRA, and Amphinema-Hebelom a.