Molecular approaches were used to re-evaluate the morphological criteria used to identify plant-associated Verticillium species. ITS-RFLPs divided the 31 studied strains of seven Verticillium species, (including the type species V. luteo-album) into four clusters. Cluster one comprised strains of the type species, V. luteo-album, cluster two V. albo-atrum, V. dahliae, V. nubilum and V. tricorpu...