EN
The aim of the presented study was to assess the sensitivity of selected Alternaria brassicae isolates to active substances of fungicides and to compare the pathogenicity of the tested fungus isolates. The pathogenicity was assessed on the leaves of cv. Californium winter rape, on which PDA medium discs overgrown with mycelium were placed. The following fungicides were used: azoxystrobin 250 g/l (Amistar 250 SC), metconazole 60 g/l (Caramba 60 SL), procymidone 500 g/l (Sumilex 500 SC) and prochloraz 250 g/l (Sportak 450 EC) in 5 concentrations. Various pathogenicity of the examined A. brassicae isolates was also confirmed. The used fungicides significantly inhibited the growth of A. brassicae colonies in comparison with the control. The growth of A. brassicae was the most reduced by the active ingredients of Sportak 450 EC and Caramba 60 SL fungicides. The influence of active ingredients on the inhibition of growth of particular isolates was diversified and depended on the used fungicide and its concentration.