Abstrakt
The serious forest pathogen Heterobasidion annosum sensu lato was found during mycological exploration in caves and underground tunnels. Seventeen isolates of Heterobasidion annosum s.l. were obtained in these habitats in the Czech Republic, Slovakia, Romania and Spain during 2008-2012.
Three species, H.abietinum, H.annosum sensu stricto, and H.parviporum, were identified by analyses of DNA sequences of three gene regions: glyceraldehyde 3-phosphate dehydrogenase, translation elongation factor 1-alfa and transcription factor. Isolates of H.parviporum were obtained from moonmilk, air and underground gallery wall.
H.parviporum recorded from Spain, Castaar de Ibor Cave, was obtained far from the natural distribution of its main host, Picea abies. Heterobasidion annosum was obtained from cave air and sediment, isopod faeces and underground gallery wall.
Heterobasidion abietinum was isolated from bat guano and outdoor air. The origin and ways of fungal dispersal are discussed.
The forest stands surrounding caves and tunnels are hypothesized as the potential source of inoculum to inhabit these unusual spaces, although the real paths of the pathogen to the habitats remain unclear.