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Summary• To demonstrate the efficacy of direct DNA extraction from hyphal ingrowth bags for community profiling of ectomycorrhizal (ECM) mycelia in soil, we applied the method to investigate the influence of long-term repeated prescribed burning on an ECM fungal community.• DNA was extracted from hyphal ingrowth bags buried in forest plots that received different prescribed burning treatments for 30 yr, and denaturing gradient gel electrophoresis (DGGE) profiles of partial fungal rDNA internal transcribed spacer (ITS) regions were compared. Restriction fragment length polymorphism (RFLP) and sequence analyses were also used to compare clone assemblages between the treatments.• The majority of sequences derived from the ingrowth bags were apparently those of ECM fungi. DGGE profiles for biennially burned plots were significantly different from those of quadrennially burned and unburned control plots. Analysis of clone assemblages indicated that this reflected altered ECM fungal community composition.• The results indicate that hyphal ingrowth bags represent a useful method for investigation of ECM mycelial communities, and that frequent long-term prescribed burning can influence below-ground ECM fungal communities.

Summary• Ectomycorrhizal (ECM) fungi were screened for laccase-like genes by polymerase chain reaction (PCR) using primers for white rot fungal laccase genes, and expression of the genes was examined by reverse transcriptase polymerase chain reaction (RT-PCR) for Piloderma byssinum in axenic culture under different nutrient conditions.• Laccase-like genes were present in Rhizopogon roseolus along with several Russulales and Atheliaceae taxa, and showed strong nucleotide sequence similarity to laccase genes in white rot fungi. Multiple laccase-like genes were only identified in Piloderma spp.• Laccase-like genes were expressed in Piloderma spp., with transcript levels some six times higher under high nitrogen conditions in P. byssinum than when nitrogen availability was lower.• The potential roles of laccases in nutrient mobilization and/or differentiation of multihyphal ECM fungal structures are discussed.

Wildfires and prescribed burns constitute widespread and potentially destructive disturbances in forest ecosystems. Fire-related effects on aboveground ecosystem components are well established, and it is known that fire can have both a direct and an indirect influence on the edaphic environment, but the effects of fire on soil-dwelling fungi are poorly understood. We review the disparate literature relating to fire effects on soil fungi, with emphasis on forest environments. A variety of effects have been reported, including altered fungal community structure along with increased or decreased mycorrhizal colonization of roots. Such effects, along with their duration, appear to be site- and (or) fire-specific, but are likely to be greater in the upper soil horizons. Where repeated burning occurs, the effects on soil fungal communities appear to be more pronounced with more frequent burning. Although fire may effect structural changes in soil fungal communities, the functional significance of such changes at the ecosystem level remains difficult to assess.