Vegetative compatibility among populations of Verticillium tricorpus and V. nigrescens in Israel

摘要

The five soilborne species of Verticillium, V. albo-atrum, V. dahliae, V. tricorpus, V. nigrescens and V. nubilum are known as plant colonizers. V. albo-atrum and V. dahliae are strong wilt-inducing plant pathogens, whereas the other three species are considered weak pathogens or saprophytes (6). Using nitrate-nonutilizing (nit) mutants, two vegetative-compatibility groups (VCGs) have been identified among collections of V. albo-atrum from the USA and Europe (3) and 3-5 VCGs have been found among several collections of V. dahliae from various sources (1,2,4,7,8,12,13). Three VCGs have been identified among about 500 strains of V. dahliae in Israel (9). No similar studies have been reported on other species of Verticillium. The objectives of this study were to determine vegetative compatibility relationships among isolates of V. tricorpus and V. nigrescens, and to characterize VCGs by morphology, temperature response and pathogenicity.