Wood-decay fungi in fine living roots of conifer seedlings.
The mycorrhizal basidiomycetes are known to have multiple, independent evolutionary origins from saprotrophic ancestors. To date, a number of studies have revealed functional resemblance of mycorrhizal fungi to free-living saprotrophs, but information on the ability of saprotrophic fungi to perform as mycorrhizal symbionts is scarce. Here, the objective was to investigate the ability of three wood-decay fungi, Phlebiopsis gigantea, Phlebia centrifuga and Hypholoma fasciculare, to colonize fine roots of conifer seedlings. For each fungus, mycorrhizal syntheses were attempted with Picea abies and Pinus sylvestris. After 24 wk, isolation of fungi and direct sequencing of fungal internal transcribed spacer (ITS) rDNA were carried out from healthy-looking surface-sterilized root tips that yielded both pure cultures and ITS sequences of each inoculated strain. Mycelial mantle of P. gigantea was frequently formed on root tips of P. abies, and microscopical examination has shown the presence of intercellular hyphae inside the roots. The results provide evidence of the ability of certain wood-decay fungi to colonise fine roots of tree seedlings.
Vasiliauskas
Rimvydas
R
Department of Forest Mycology and Pathology, Swedish University of Agricultural Sciences, PO Box 7026, SE-750 07 Uppsala, Sweden.
Menkis
Audrius
A
Department of Evolutionary Biology, Uppsala University, Norbyvägen 18 D, SE-752 36 Uppsala, Sweden.
Finlay
Roger D
RD
Department of Forest Mycology and Pathology, Swedish University of Agricultural Sciences, PO Box 7026, SE-750 07 Uppsala, Sweden.
Stenlid
Jan
J
Department of Forest Mycology and Pathology, Swedish University of Agricultural Sciences, PO Box 7026, SE-750 07 Uppsala, Sweden.
D000363:Agaricales / Q000166:cytology / Q000502:physiology*; D025282:Mycelium / Q000166:cytology; D028222:Picea / Q000382:microbiology*; D041605:Pinus sylvestris / Q000382:microbiology*; D018517:Plant Roots / Q000382:microbiology*; D020072:Polyporales / Q000166:cytology / Q000502:physiology*; D036226:Seedlings / Q000382:microbiology*