Postharvest Melatonin Treatment Modulates Antioxidant Defense System and Delays Ripening in Mango (Mangifera indica L.) cv. Dashehari
Kripa Shankar Yadav
Chandra Shekhar Azad University of Agriculture and Technology, Kanpur (U.P.), India.
A. K. Trivedi
ICAR- Central Institute for Subtropical Horticulture, Lucknow (U.P.), India.
V. K. Tripathi *
Chandra Shekhar Azad University of Agriculture and Technology, Kanpur (U.P.), India.
*Author to whom correspondence should be addressed.
Abstract
Mango (Mangifera indica L.) cv. 'Dashehari' is a highly esteemed climacteric fruit whose commercial value is constrained by a short postharvest shelf life owing to rapid ripening and senescence under ambient storage conditions. This study investigated the effectiveness of postharvest melatonin dip treatments (0, 50, 100, 150, and 200 µM) in regulating biochemical, enzymatic, and quality attributes of 'Dashehari' mangoes stored at ambient temperature (27±2°C, 75±2% RH) for 12 days. Fruits treated with melatonin exhibited a marked delay in ripening-associated changes, including reduced weight loss and better retention of firmness, indicating enhanced structural integrity throughout storage. Among the concentrations tested, 200 µM melatonin was most effective, significantly slowing the accumulation of total soluble solids and sugars, reflecting suppressed carbohydrate catabolism, while maintaining higher titratable acidity. This treatment also conserved bioactive compounds, evidenced by greater retention of total phenolics and flavonoids compared with untreated fruit. Additionally, melatonin-treated fruits displayed pronounced upregulation of antioxidant enzymes, catalase and peroxidase, indicating strengthened enzymatic defence against oxidative stress and reactive oxygen species accumulation during senescence. These physiological and biochemical modulations collectively contributed to delayed ripening, improved shelf life, and superior nutritional quality retention. The results demonstrate that 200 µM melatonin dip treatment is an effective, economical, and eco-friendly postharvest management strategy for extending shelf life and preserving the quality of 'Dashehari' mango under ambient storage conditions, with potential application for other climacteric fruits requiring extended postharvest longevity and reduced reliance on synthetic preservation methods.
Keywords: Melatonin, postharvest treatment, antioxidant enzymes, shelf-life extension, total phenolics, climacteric fruit, oxidative stress