Management of Alternaria solani in Tomato Using Withania coagulans- an Alternative to Chemical Control

To reduce pesticide resistance in plant pathogens, alternate approaches are needed to be explored. In this study, dried powder of Withania coagulans was evaluated for the management of Alternaria solani causing early blight disease in tomato both in vitro and in planta. Different dried powder doses (5, 10, and 15% w/v) of different parts (succulent shoot, stem and leaves) of W. coagulans were tested against in vitro growth of Alternaria solani through food poisoned technique. Also, different dried powder doses (15 and 30 g kg-1 soil) of different parts (succulent shoot, stem and leaves) of W. coagulans were applied to soil at different application times [5, 10, and 15 Days Before Transplantation (DBT)] and were evaluated for the control of early blight in tomato plants under screen house conditions. Results from in vitro studies showed that the highest dose 15% (w/v) and succulent shoot plant part showed a maximum antifungal activity. Results from screen house experiment showed that the highest dose of 30 g kg-1 soil and longest application time of 15 DBT of succulent shoot dried powder suppressed the disease severity effectively in tomato plants (artificially inoculated with Alternaria solani) resulted in significantly higher root length, shoot length, and fresh biomass. Results of this study suggested that succulent shoot dried powder at 30 g kg-1 of soil applied at 15 DBT can be used for the management of tomato early blight disease under screen house conditions.