Exogenous Melatonin Attenuates Post-harvest Decay by Increasing the Antioxidant Activity of Wax Apple (Syzygium samarangense)

Our experiments show that exogenous MT treatment can effectively delay the decay and water loss rate of post-harvest wax apples, which may be related to reducing the degree of membrane lipid peroxidation and inhibiting enzymatic browning. MT treatment also maintains the quality of post-harvest wax apple by enhancing the activity of antioxidant enzymes. At the same time, it can reduce the incidence of post-harvest diseases of wax apple by increasing the JA and SA contents. MT can down-regulate the expression of genes related to oxidation, and up-regulate the expression of related genes in antioxidant enzymes and non-enzymatic antioxidant pathways, suggesting that exogenous melatonin can reduce the production of excess ROS and maintain the redox homeostasis of post-harvest wax apple. Therefore, melatonin, as a strong and effective free radical scavenger and antioxidant, plays an important role in delaying the decay of post-harvest wax apples and prolonging the shelf life. Overall design: Using IlluminaHiseq4000, de novo transcriptome sequencing was performed on the 5th day of wax apple samples, including control group and 800µM melatonin (MT) treatment group, including 3 biological repeats.