Intra- and interspecific relations within Laccaria bicolor sensu lato

Abstract

Interstock pairing analyses were undertaken using isolates obtained from a number of specimens belonging to L. bicolor sensu lato. Three intersterility groups were detected among the tested North American isolates. The two employed Swedish isolates were completely intercompatible with one North American group but only somewhat intercompatible with the other two groups. These data are more or less concordant with those obtained by RFLP analysis of mtDNA and rDNA. Phenetic analyses of these and other collections revealed that the intersterility groups could be delimited on basidioma morphology. Synthesis of these data indicate that the North American members of the complex should be recognized as three distinct species: L. bicolor sensu stricto, L. nobilis, and L. trichodermophora. Data is needed on additional European collections referable to the L. bicolor complex to determine the significance of the observed anomalies in interstock pairing data and the divergence in rDNA of these isolates from North American isolates. These studies support the use of a multifaceted approach to solving taxonomic problems and obtaining information on speciation and the biology of agarics that form ectomycorrhizae.