MOLECULAR CHARACTERIZATION OF THE PLANT PATHOGEN VERTICILLIUM-DAHLIAEKLEB USING RAPD-PCR AND SEQUENCING OF THE 18SRRNA-GENE

Thirty-four isolates of Verticillium dahliae Kleb. from nine different genera of dicotyledonous host plants and a broad range of geographic regions were analysed genotypically. Random amplified polymorphic DNA (RAPD) markers were used for the estimation of the genetic variability within the species. Using four primers for the analysis, 79 distinct fragments were obtained. The derived phenogram clustered the isolates in two main groups: one consisted almost entirely of V. dahliae isolat es from oilseed rape (Brassica napus napus), the other group comprised isolates from a wide range of host plants. No correlation between geo graphic location of the isolates and the RAPD-pattern was observed. Se quencing of the gene for the 18SrRNA and calculation of the phylogenet ic tree integrated the deuteromycetous fungus V. dahliae into the sexu al system of the filamentous ascomycetes.