Studies on compatibility of biocontrol agents with chemical fungicides for integrated management of Alternaria leaf spot of cabbage

Abstract

The compatibility of fungal biocontrol agents (Trichoderma viride and T. harzianum) and bacterial biocontrol agents (Bacillus subtilis) was assessed with chemical fungicides viz., propiconazole, hexaconazole, tebuconazole and copper oxychloride. Studies on the compatibility of these effective fungicides and bioagents revealed that the triazole fungicides viz., propiconazole, hexaconazole, tebuconazole completely inhibited the growth of two bioagents viz., T. viride and T. harzianum at all the three concentrations but compatible with B. subtilis at all the three concentrations. The percentage of inhibition of T. viride with copper oxychloride was 61.4, 74.4 and 80 % and with T. harzianum was 65.5, 80.0 and 85.5% at 0.1%, 0.2% and 0.4% concentrations respectively. Copperoxy chloride found to be incompatible with B. subtilis as inhibition zone increased with increase in the concentration of fungicide.