The chemical treatments combined with antagonistic yeast control anthracnose and maintain the quality of postharvest mango fruit

During the storage and transportation of the mango fruit, the major source of disease is anthracnose, caused by the fungus Colletotrichum gloeosporioides. The objective of this study is to find an appropriate method that not only reduces mango decay but also maintains its postharvest quality. The effects of chemicals, the use of the yeast species Metschnikowia pulcherrima and their combination on storage quality, focusing on the enzyme activity related to disease of Tainong mangos was studied. By immersing the mangoes in M. pulcherrima suspension (1.0×10⁸ cfu mL⁻¹), salicylic acid (SA) solution (50 mg L⁻¹) or calcium chloride (CaCl₂) solution (1.0 g L⁻¹), the lesion expansion and decay of the mango fruit caused by C. gloeosporioides could be significantly delayed. These treatments also delayed the changes in quality traits (a* value, firmness, contents of total soluble solids (TSS) and vitamin C (Vc), while the activities of anti-disease enzymes such as polyphenol oxidase (PPO), phenylalanine ammonia lyase (PAL), chitinase (CHT) and β-1,3-glucanase (GUN) were enhanced as compared to the control treatment. Furthermore, the combination of SA solution, CaCl₂ solution and M. pulcherrima suspension presented an additive effect, increasing the efficacy in controlling the disease and maintaining the storage quality of mango fruits. Taken together, our data suggest that the integration of chemical treatments combined with M. pulcherrima could be an alternative to the use of fungicides in postharvest treatment of the mango fruit, specifically for improving storage quality as well as the control of the anthracnose.