Assessing the Baseline Sensitivity of Predominant Soil-Borne Pathogens against Carbendazim

Fungicide resistance is reducing the effectiveness of fungicides in controlling plant diseases, leading to increase crop losses and the need for alternative control strategies. Addressing this issue requires careful fungicide use and the development of new management approaches. The main objective of present study was to determine the baseline sensitivity and development of fungicide resistance in predominant soil-borne pathogens against carbendazim at various concentrations. It was observed that the EC50 of Fusarium oxysporum and Macrophomina phaseolina was 9.970 and 16.294 µg ml-1, respectively. The baseline sensitivity of both fungi was determined based on the inhibition percentage at which the pathogen showed sensitivity. Repeated transfer of these cultures at same concentrations for some generations showed the progressive decline in growth inhibition across generations resulting in the development of fungicide resistance. These studies have demonstrated that overreliance on certain fungicides can lead to the development of resistant fungal strains, compromising the efficacy of disease management. This emphasizes alternative use of fungicides with different mode of action or following integrated disease management strategies to mitigate fungicide resistance and sustainably protect crops.