Resistance of cucumber plantlets to culture filtrate of Fusarium oxysporum is correlated with resistance of single cells from callus. Single cells and plantlets of two cultivars of cucumber were incubated with culture filtrates. Rapid cell death occurred, as assessed by the stain fluorescein diacetate. More cell death ocurred in the cells of the cultivar Aodai than in to cells of the cultivar Caipira, which presented high level of resistance. Maximum toxic activity of culture filtrates was attained after 21-25 days of growth of the fungus.
Fusarium oxysporum; single cells; cucumber; toxic metabolites