Control of postharvest anthracnose of banana using a new edible composite coating

Anthracnose is a postharvest disease of banana caused by the fungus Colletotrichum musae that results in major economic losses during transportation and storage. For the management of banana anthracnose, antifungal effects of Arabic gum (AG) (5, 10, 15 and 20%), chitosan (CH) (1.0%), and the combination of AG with CH were investigated in vitro as well as in vivo. CH at 1.0% and 1.5% had fungicidal effects on C. musae. AG alone did not show any fungicidal effects while the combination of 1.0% CH with all tested AG concentrations had fungicidal effects. However, the potato dextrose agar (PDA) medium amended with 10% AG incorporated with 1.0% CH showed the most promising results among all treatments in suppressing the mycelial growth (100%) and conidial germination inhibition (92.5%). In vivo analysis also revealed that 10% AG incorporated with 1.0% CH was the optimal concentration in controlling decay (80%), showing a synergistic effect in the reduction of C. musae in artificially inoculated bananas. The 10% AG incorporated with 1.0% CH coatings significantly delayed ripening as in terms of percentage weight loss, fruit firmness, soluble solids concentration and titratable acidity. The results showed the possibility of using 10% Arabic gum incorporated with 1.0% chitosan as a biofungicide for controlling postharvest anthracnose in banana.