In vitro compatibility of Bradyrhizobium japonicum with systemic fungicides

Abstract

The bacterium B japonicum was successfully isolated from functional root nodules of soybean plants. In vitro evaluation, by inhibition zone technique revealed all of the seven each systemic and non-systemic at their recommended field dosages (100% RD), 50% and 125% of the RD showed both synergistic and toxic effects against B. japonicum. Out of the seven systemic fungicides tested carbendazim 50% WP and hexaconazole 5% EC tested at all three concentrations were found highly compatible with B. japonicum and rest of the five fungicides viz., tebuconazole 25% WG, thiophanate methyl 75% WP, difenconazole 25% EC, propiconazole 25% EC and pyraclostrobin 20% WG were non-compatible with the test bacterium.