Unravelling effects of red/far-red light on nutritional quality and the role and mechanism in regulating lycopene synthesis in postharvest cherry tomatoes.

• Red/far-red light inhibited weight loss and promoted colour change during storage. • Red/far-red light enhanced nutritional quality of cherry tomato compared to control. • Red/far-red light up regulated PSY and ZDS expression to increase lycopene content. • Red/far-red light induced HY5 expression through activated PHYA/B to induced PSY. • Elevated HY5 also increased expression of ACS2 to induce RIN , then promote PSY. The main goal of this study was to explore the role of red/far-red light in the preservation of postharvest quality in cherry tomato fruits and the mechanism of red/far-red light in regulation of lycopene synthesis. Results showed that red/far-red light irradiation inhibited weight loss and promoted colour change during storage, and it also increased the content of lycopene and β-carotene compared to control. Gene PSY , ZDS and LCY-b were overexpressed in fruits treated with red/far-red light during 33 days' storage compared to control. The analysis of genes involved in red/far-red light absorbance (PHYA and PHYB) and mediation (HY5 and PIF3), and fruit ripening (ACS2 and RIN) suggests that red/far-red light promote lycopene accumulation through phytochrome-mediated signalling pathway to induce HY5. Elevated HY5 could either directly bind to PSY or promote the expression of ACS2 to induce RIN through MADS-loop to enhanced lycopene content. [ABSTRACT FROM AUTHOR]