Diversity and dynamics of the fungal community in Lake Ohrid

Abstract

Fungi are universally present in freshwater systems and are of greatsignificance in the structural and functional organization of theseecosystems. The aim of this study was to assess the diversity of fungalcommunities in the ancient, oligotrophic Lake Ohrid and to investigatetheir spatial and temporal dynamics. The fungal community in Lake Ohridconsists of 36 species identified from 213 isolates. The autochthonouscommunity is made up of 10 species belonging to the ordersSaprolegniales and Peronosporales: Achlya americana, A. racemosa,Aphanomyces leavis, Dictyuchus monosporus, D. sterile, Pythium ultimum,Saprolegnia ferax, S. hypogina, S. monoica, and Saprolegnia sp. Theallochthonous community is composed of 26 species from 15 genera offungi. The dominant genera are Aspergillus (5 species, 13.86% ofdetermined species), Penicillium (6 species, 16.66%), and Cladosporiumand Fusarium (3 species, 8.33%). The species Kloeckera apiculata,Didiostible sp., Gliocladium roseum, and Varicosporium delicatum areidentified here for the first time in freshwater ecosystems of theBalkans. Quantitative analysis of the fungal community showed that thenumber of propagules varied in the range of 0 to 19.5 x 10(3) l(-1). Thediversity and abundance of both the autochthonous and the allochthonousfungal communities are greater in the littoral than in the pelagialzone. Our results represent the first hydromycological data for LakeOhrid the region of Macedonia.