Taxonomic status of putative Verticillum alboatrum isolates

Two fungal isolates, formerly classified as Verticillium alboatrum and prop osed as forming the basis of a new sub-group ('Group 2') within the species . have been shown to be non-pathogenic to known hosts of II alboatrum and, on the basis of molecular evidence, to be closely related to Verticillium p salliotae and Verticillium fungicola. We propose that the taxon V. alboatru m be confined to those closely related isolates, usually plant pathogenic a nd usually producing dark resting mycelium, referred to by other authors as Group 1. The only sub-specific groupings which appear valid (based on path ological and molecular evidence) comprise: (1) host-adapted isolates from l ucerne; and (2) all other isolates. (C) 1999 Federation pf European Microbi ological Societies. Published by Elsevier Science B.V. All rights reserved.