Preharvest methyl jasmonate and salicylic acid treatments improve the nutritional qualities and postharvest storability of tomato

Recent studies claim that preharvest exogenous treatments with salicylic acid (SA) and methyl jasmonate (MeJA) mimic stress and enhance phytochemical compounds in different crops. In this study, antioxidant properties (total phenolics, flavonoids, vitamin C, lycopene, and & beta;-carotene), antioxidant activities, free amino acid contents (mainly GABA), and storage qualities were investigated in preharvest MeJA- and SA-treated and the control fruit of 'Kumato' tomato during 24 d storage period at 12.5 degrees C, to examine whether MeJA and SA treatments affect storability and nutritional quality. The results showed that 0.5 mM SA and 0.25 mM MeJA maintained the firmness and TSS, and reduced weight loss and ethylene production of 'Kumato' tomato without affecting its color development. MeJA was more effective than SA in improving the contents of essential amino acids and maintaining the contents during the storage period. In contrast, SA was more effective than MeJA at enhancing the total amino acid content. However, there was no evident advantage of preharvest SA and MeJA treatment over the control regarding GABA content. The overall results of secondary metabolites suggest that the preharvest MeJA and SA treatments improve the biosynthesis of phytochemical compounds throughout the storage period. In addition, this study confirms the benefits of these treatments in increasing the antioxidant activities during the storage period without compromising sensory qualities. Based on the findings, preharvest MeJA and SA could be considered for commercial application to maintain the quality and antioxidant properties of tomatoes at harvest and during the storage period. However, further research is needed to explore the effects of these treatments on various tomato cultivars.