The effect of selected fungicides on survival of Agrobacterium tumefaciens (Smith et Townsend) Conn in various types of soils

In fertile, nonsterile soil Dithane M-45 (macozeb), Euparen 50 WP (tolyfluanid), Kaptan 50 WP (captan) and Ridomil Gold 80 WP (metalaxyl) at concentration of 1000 ppm showed the highest antibacterial activity. Similar trends in activity of these fungicides occurred in fertile, sterile soil, however a little lower in case of Kaptan and Euparen. In most of investigated soil Befran 25 SL (imimnoctadyne), Syllit 65 WP (dodine) and Thiram Granulfo 80 WG (thiram) increased bacteria number. In sandy acidic soil (pH 3.5) all tested fungicides totally eliminated bacteria. On the other hand in sandy neutral soil only Dithane, Euparen, Kaptan and Ridomil showed such activity. The fold decrease of fungicides concentration generally did not influence. Kaptan and Ridomil effectiveness but it decreased the activity of Dithane and Euparen