Colonization of root systems of Carex flacca and C-pilulifera by Cortinarius (Dermocybe) cinnamomeus

The root systems of Carex flacca and C. pilulifera, growing in the Burren (western Ireland), were shown to be colonized by Cortinarius (Dermocybe) cinnamomeus. This basidiomycete formed ectomycorrhiza-like structures, which possessed a distinct fungal mantle (85-100 mum thick), hyphal infection in epidermal cells, rhizomorphs and extramatrical hyphae, but lacked a Hartig net. These ectomycorrhiza-like structures were formed on first-order lateral roots but were distinct, morphologically and anatomically, from dauciform roots. Structures typical of arbuscular mycorrhizas were never observed. The colonization of root systems of C. flacca by C. cinnamomeus was confirmed by PCR/RFLPs and DNA sequencing of the ITS region of rDNA.