Hyphae of waxcap fungi colonise plant roots

The trophic strategy of the globally distributed waxcaps(Hygrophoraceae) is uncertain. Some clues point to a biotrophic mode,particularly the 13C and 15N (stable isotopes) signatures. Theobservation of dense basal hyphae of Hygrocybe fruit bodies being tightlyattached to live fine roots may be indicative of a plant-derivednutritional habit. To further scrutinize this fungus-plant association,stipe base samples and attached plant fragments were examinedhistologically. Waxcap hyphae were found growing inside live fine rootsof associated vegetation. Amplication and sequencing of waxcap DNA fromliving root tissues using species-specific PCR primers also confirmedtheir presence in live plant roots. We therefore conclude that this groupof fungi has a biotrophic lifestyle with plants.The trophic strategy of the globally distributed waxcaps (Hygrophoraceae) is uncertain. Some clues point to a biotrophic mode, particularly the 13C and 15N (stable isotopes) signatures. The observation of dense basal hyphae of Hygrocybe fruit bodies being tightly attached to live fine roots may be indicative of a plant-derived nutritional habit. To further scrutinize this fungus–plant association, stipe base samples and attached plant fragments were examined histologically. Waxcap hyphae were found growing inside live fine roots of associated vegetation. Amplification and sequencing of waxcap DNA from living root tissues using species-specific PCR primers also confirmed their presence in live plant roots. We therefore conclude that this group of fungi has a biotrophic lifestyle with plants