Effectiveness of postharvest treatment with chitosan and other resistance inducers in the control of storage decay of strawberry

Abstract

This study compared the effectiveness of practical grade chitosan when used in solution with acetic, glutamic, formic and hydrochloric acids, and a water-soluble commercial chitosan formulation, in controlling postharvest diseases of strawberry. The commercial chitosan formulation and other resistance inducers based on benzothiadiazole, oligosaccharides, soybean lecithin, calcium and organic acids, and Abies sibirica and Urtica dioica extracts were also tested. The commercial chitosan formulation was as effective as the practical grade chitosan solutions in the control of gray mold and Rhizopus rot of strawberries immersed in these solutions and kept for 4days at 20±1°C. Moreover, the treatment with commercial and experimental resistance inducers reduced gray mold, Rhizopus rot and blue mold of strawberries stored 7days at 0±1°C and then exposed to 3days shelf-life. The highest disease reduction was obtained with the commercial chitosan formulation, followed by benzothiadiazole, calcium and organic acids. The compounds that provided the best results in postharvest applications to control storage decay of strawberries, should be tested in further trials through preharvest treatments, applied at flowering and a few days before harvest.