Three Polish, four other European and three tropical isolates of the nematophagous fungus Verticillium chlamydosporium were screened for their ability to colonise the surface of barley roots, produce chlamydospores and infect eggs of Meloidogyne incognita in laboratory tests. PCR-fingerprinting of different Polish isolates and YclO was used to detect differences between isolates. Among the European isolates, the Polish isolate which came from a field fertilised with manure produced the greatest number of viable chlamydospores, the largest proportion of infected eggs of Meloidogyne incognita and the most prolific root colonisation. Among the tropical isolates, an isolate A produced the largest number of chlamydospores and an isolate B was the most prolific root coloniser and parasitised most of M. incognita eggs.