A combination of gum arabic and chitosan can control anthracnose caused by Colletotrichum musae and enhance the shelf-life of banana fruit

Anthracnose, caused by Colletotrichum musae, is the major disease affecting the quality of banana fruit during storage. To control banana anthracnose, the combined effects of coatings with gum arabic [GA; at 5, 10, 15 or 20% (w/v)] and 0.75% (w/v) chitosan (CH) were investigated and compared to untreated controls. In vitro results showed significant (P < 0.05) inhibition of mycelial growth and conidial germination of C. musae in all combined treatments compared to the untreated controls after 7 d of incubation at room temperature (25 C). However, potato dextrose agar (PDA) plates amended with 10% (w/v) GA gave the most promising results among all test treatments in suppressing mycelial growth (86%) and inhibiting conidial germination (80%), while no effective inhibition of conidial germination was observed in the controls. In vivo results confirmed that 10% (w/v) GA was the optimum concentration to control fruit decay (70%), while showing efficacy on the reduction of growth of C. musae on artificially inoculated banana fruit. The combined coatings of GA + CH also significantly delayed ripening in terms of weight loss, fruit firmness, soluble solids content, and titratable acidity. These results support the possibility of using 10% (w/v) GA combined with 0.75% (w/v) CH as an alternative strategy to control post-harvest anthracnose disease in banana fruit.