Browsing by Subject "valkolaho"

There is a vast diversity of fungi of Finnish forests that include species of, for example, the wood decaying polypore Bacidiomycota, wood-inhabiting Ascomycota, tree-associated mycorrhizal fungi and litter-decaying fungi living on the top surface of the soil. These fungi have an influence to tree growth and carbon circulation in the forest ecosystems of the Northern Hemisphere. Brackets, aphyllophoroid fungi as well as some gilled mushrooms are used as indicator species in the conservation of forests, forest environments and meadows. Fungal community in wood is in a constant change. Some fungal species or isolates of the same species affect positively on others, and may increase the growth of mycelia. In contrast, some species may have negative effect. Depending on the nature of the vegetative interaction, the fungal species may be either strong or weak combetitors. A change in the combative situation can affect the outcome of the interaction greatly. Some species are strong combatant upon the interaction of two species. Upon interaction of several species, or between different isolates, the outcome may dramatically change, and a previously weaker combatant may prove to be strong. This study examined the influence of Fomitopsis pinicola, which is a common wood-decaying brown rot polypore species in Finnish forests, on the growth and enzyme production of five wood-decaying white rot fungal species. Activities of several wood-degrading enzymes (laccase, manganese peroxidase, xylanase, endoglucanase, β-glucosidase) were studied for individual species, and in co-cultures of various combinations of the species for eight weeks on liquid media including coniferous wood shavings. All co-cultures included F. pinicola, and either one or two additional species.The hyphal extension growth rate on malt agar medium was quantified for each species, and the fungal biomass increment (as a dry weight) and acidification of the growth liquid were measured from malt extract broth media cultures. F. pinicola proved to be by far supreme colonizer on malt agar and its hyphae were advancing over the mycelia of the white rot species studied. Phlebia radiata formed mycelial blocks against the other white rot fungi but not against F. pinicola. In most cases, acidification of the liquid medium proved to be beneficial for fungal growth (dry weight). Except for F. pinicola, acidification of the culture fluid was moderate in the single species cultivations, and in the co-cultivations including P. radiata. Number of fungal species had no clear effect on the enzyme activity values in the co-cultivations, yet P. radiata increased the activities of laccase and manganeseperoxidase. Also Trichaptum abietinum had an influence on laccase activity. In conclusion, in polyporous fungal co-cultivaltions, a few species had an impact to fungal growth and and production of wood-decaying enzymes when cultivated on coniferous wood.