Red Light Irradiation Modulates Reactive Oxygen Species Homeostasis and Redox Signaling in Different Parts of Mango Fruit During Postharvest Ripening

To investigate the differences in reactive oxygen species (ROS) metabolism and signal transduction between the illuminated and non-illuminated surfaces of mangoes exposed to red light, this study used “Tainong No.1” mangoes as the test material, setting up three groups: mango exposed to red light, mango without red light and mango in darkness. The study measured maturity physiological indicators, ROS content, antioxidant enzyme activity, non-enzymatic substances, and combinations with DIA proteomics analysis. The results showed that red light exposure promoted the overall ripening of mangoes, and there was almost no difference in ripening between mango exposed to red light and mango without red light. Red light mainly induced rapid accumulation of hydrogen peroxide in the peel of the irradiated area and stimulated the synthesis of superoxide anion in the pulp. The antioxidant capacity of both the irradiated and non-irradiated areas was enhanced. Key proteins in the ROS signaling pathways such as Rab11, LRK-RLK, and PIN3 were significantly upregulated. In summary, red light promotes synchronous ripening of mango fruits by coordinately regulating the ROS homeostasis of the tissue, and provides new insights into the use of light signals for regulating fruit metabolism.