A comparative analysis of the cultured micromycetes in oligotrophic peatlands of natural biosphere reservations located in the northern and central parts of Russia

Abstract

The current study addresses the fungal diversity of the peatlands that vary geographically and geologically, in the central and northern parts of Russia. The central (Smolenskaya area, National Park «Smolenskoye Poozerie») and northern (White Sea Biological Station area) peatlands have a different geological history, the former have a glacial origin, while the latter are of marine origin. Our aim was to investigate the fungal biota of these zones full of Sphagnum moss, and possibly reveal the species that are pertinent to these particular habitats.In both investigated areas, we found an overall poor species diversity with a high fraction of sterile mycelia. Many penicillia species were dominating in all peat samples -P. thomii, P. spinulosum, P. glabrum, P. funiculosum, P. aurantiogriseum (together with Geotrichum candidum), many of them are known to degrade Sphagnum. We were particularly interested in the dynamics of the species from the genus Oidiodendron that have been shown to be involved in primary Sphagnum degradation. The northern area contained a larger species diversity of Oidiodendron, as compared to the central zone. Interestingly, insect-associated species of the genus Tolypocladium and Beauveria, along with the psychrotolerant species of Geomyces and Tolypocladium were recovered only from the northern peatlands. Aspergillus spp. were found in peatlands of the central zone only. We link this result to the climatic features of the area, but also different invertebrate contents that may be utilized by fungi. We detected a tendency of an increasing diversity of Oidiodendron species, psychrotolerant and entomopathogenic fungal species as well as a proportion of sterile forms in the northern area.