Melatonin improves the storage quality of rabbiteye blueberry (Vaccinium ashei) by affecting cuticular wax profile

•MT delayed the decline of total wax by 15.17% in ‘Garden Blue’ at the 21th day of storage.•MT induced the accumulation of alkanes and triterpenoids in ‘Garden Blue’ and ‘Baldwin’, respectively.•MT reduced water loss by 35.61% in ‘Baldwin’ and 62.90% in ‘Garden Blue’ at the 35th day of storage.•Triterpenoids and fatty acids were negatively correlated with water loss during storage. Cuticular wax is the first line of structural defense for plants against external stresses. This study investigated the effects of melatonin (MT) on chemical composition and accumulation profile of wax, as well as fruit quality of rabbiteye blueberry during storage. The results indicated a significant reduction in the overall wax content during storage. Nevertheless, MT effectively delayed the decline, with a higher amount of 9.8% and 15.17% in the treated ‘Baldwin’ and ‘Garden Blue’ compared to their respective controls at 21st day of storage. The wax composition significantly varied depending on storage time, MT treatment, and cultivars. Additionally, MT markedly improved the fruit quality of rabbiteye blueberries. Correlation analysis revealed water loss and decay rates were negatively correlated with triterpenoids and fatty acids. Taken together, this study highlights the positive effects of post-harvest MT application on shelf life and fruit quality of blueberry by modifying the wax profile during storage.