Molecular and morphological discrimination betweenTylospora fibrillosaandTylospora asterophoramycorrhizae

摘要

Among the mycorrhizal types of spruce,Tylospora-type mycorrhizae are the most constant and abundant. Two species of the genusTylosporaoccur in Europe,Tylospora fibrillosaandTylospora asterophora. Mycorrhizae ofT. asterophoraare described in detail for the first time. Sequences of the internal transcribed spacer (ITS) of the ribosomal genes were obtained fromT. fibrillosaandT. asterophoramycorrhizae, sporocarps, and cultured mycelium. Discrimination and identification of the two species by ITS polymerase chain reaction - restriction fragment length polymorphism (PCR-RFLP) are discussed in the light of inter- and intra-specific variability. Species-specific PCR primers were designed to distinguish both species. Molecular screening ofTylospora-type mycorrhizae from field material led to unambiguous results, whereas morphological identification is likely to fail because of great similarity even at the microscopic level.Key words:Tylospora asterophora,Tylospora fibrillosa, ectomycorrhizae, taxon specific primers (TSOPs), ITS sequences.