Fungal associations of serially washed healthy non-mycorrhizal roots of Picea abies

Abstract

The mycoflora of serially washed healthy fine roots of Norway spruce ( Picea abies ) from six climatically and edaphically different sites in Southern Bavaria was examined. More than 120 taxa were detected. Mycelium radicis atrovirens α was most frequently isolated and occurred in up to 70% of roots. Three main types of fungal associations were identified among sites. Soil pH and altitude had a decisive influence on the type of association. Fungal associations on roots in alkaline soil at low altitudes were dominated by Cylindrocarpon destructans with Cryptosporiopsis sp., Idriella lunata, Mortierella alpina, M. minutissima and Mucor hiemalis f. hiemalis as the other major components. A second type of fungal association formed on roots in peat. Trichoderma viride was the most typical representative of this association, although M. radicis atrovirens α was more frequent. M. radicis atrovirens α was also the dominant fungus of the third association, which formed in both acidic soil and alkaline soil at high altitude. The possible relationships between M. radicis atrovirens α or C. destructans and Norway spruce are discussed.