Postharvest control of Botrytis gray mold in tomato by antagonists and biorational compounds

Abstract: The fungal pathogen Botrytis cinerea causes severe rots on tomato fruit during storage and shelf life. Continuous use of synthetic fungicides has produced an increasing public concern regarding contamination of edible crops with toxic residues, and proliferation of resistance in the pathogen populations. These facts have led to a search for new alternative control measures in a more ecological way. This study evaluates efficacy of biocontrol agents (Trichoderma harzianum and Epicoccum nigrum), botanicals (Lippia alba and garlic extracts) and low-risk chemicals such as salicylic acid (SA), sodium bicarbonate (SB), potassium chloride (PC) and sodium phosphate dibasic (SP) against gray mold caused by B. cinerea on postharvest tomato fruits. The fruits were obtained in packinghouse, being washed and disinfected with sodium hypochlorite. Artificially wounded fruits were treated sequentially with each bio-agent and the pathogen. After 1 week of incubation in plastic trays, the soft rot lesion diameters were evaluated. Results obtained have demonstrated that the treatment with T. harzianum, E. nigrum, PC, SP and garlic extract reduced significantly the gray mold infections from 95 up to 99% compared to the control treated with B. cinerea alone. These findings indicate that these environmentally friendly agents have the potential to control postharvest gray mould on tomato fruits in an integrated pest management strategy.