Restriction fragment length polymorphisms in mitochondrial DNA and ribosomal RNA gene complexes as an aid to the characterization of species and sub-species populations in the genusVerticillium

Abstract

Genomic DNA was extracted from seven species of Verticillium and digested with the restriction endonucleases EcoRI or HaeIII. Hybridization with an homologous V. albo-atrum ribosomal RNA gene probe revealed restriction fragment length polymorphisms (RFLPs) which could differentiate V. lateritium, V. lecanii, V. nigrescens, V. nubilum and V. tricorpus. Digestion with EcoRI did not provide RFLPs which could distinguish between V. albo-atrum and V. dahliae. Digestion of genomic and mitochondrial DNA with HaeIII showed distinctive patterns on ethidium bromide gels which allowed each species to be distinguished. Some intra-species variation in patterns occurred and a combination of mitochondrial and ribosomal RNA gene complex RFLPs has potential as an aid for the characterization of species and sub-species populations in the genes Verticillium.