EN
The paper presents results of research into the effect of magnesium and zinc ions, Miedzian 50 WP and Topsin M 70 WP fungicides and Dispersive Afalon 450 SC and Racer 250 WP herbicides on the development and bioactivity of the following isolates of antagonistic fungi: Trichoderma harzianum Rifai, Trichoderma pseudokoningii Rifai and Trichoderma viride Pers. ex Gray. There was defined an effect of the said factors in different concentrations on mycelium growth and germination of Trichoderma genus fungi spores and on their antagonistic activity towards fungi pathogenic for plants. It was observed that the factors studied affected the Trichoderma genus fungi tested, with reactions of fungi depending on the kind of factor, its concentration and on the fungus isolate. There were recorded some powerful fungistatic properties of zinc ions in concentrations of 1000 and 3000 ppm and Topsin M 70 WP, Dispersive Afalon 450 SC and Racer 250 WP in the dose of 100 ppm.