Gamma irradiation delays tomato (Solanum lycopersicum) ripening by inducing transcriptional changes

BACKGROUNDTomato (Solanum lycopersicum) has a relatively short shelf life as a result of rapid ripening, limiting its transportability and marketability. Recently, gamma irradiation has emerged as a viable method for delaying tomato fruit ripening. Although few studies have shown that gamma irradiation delays the ripening of tomatoes, the underlying mechanism remains unknown. Therefore, the present study aimed to examine the effects of gamma irradiation on tomato fruit ripening and the underlying mechanisms using transcriptomics. RESULTSFollowing gamma irradiation, the total microbial count, weight loss, and decay rate of tomatoes significantly reduced during storage. Furthermore, the redness (a*), color change ( increment E), and lycopene content of gamma-irradiated tomatoes decreased in a dose-dependent manner during storage. Moreover, gamma irradiation significantly upregulated the expression levels of genes associated with DNA, chloroplast, and oxidative damage repairs, whereas those of ethylene and auxin signaling-, ripening-, and cell wall metabolism-related, as well as carotenoid genes, were downregulated. CONCLUSIONGamma irradiation effectively delayed ripening by downregulating the expression of ripening-related genes and inhibiting microbial growth, which prevented decay and prolonged the shelf life of tomatoes. (c) 2023 The Authors. Journal of The Science of Food and Agriculture published by John Wiley & Sons Ltd on behalf of Society of Chemical Industry.

Automated summary

Tomato has a short shelf life, but gamma irradiation can effectively delay its ripening and extend its storage period, as shown in this study. Gamma irradiation reduced microbial growth and decay of tomatoes, while also affecting their color and lycopene content. The underlying mechanism involves the upregulation of genes related to DNA and chloroplast repairs, as well as the downregulation of genes associated with ripening and carotenoid production.