Impact of exogenous salicylic acid treatment on the cell wall metabolism and ripening process in postharvest tomato fruit stored at ambient temperature

Abstract

Abstract Tomato is a climacteric fruit susceptible to rapid softening and ripening after harvest. In this study, the changes of physicochemical characters, cell wall‐degrading enzymes, cell wall compositions and ethylene production of ‘Hisar Arun’ and ‘BSS‐488’ tomato fruits were investigated under the influence of salicylic acid treatment. Salicylic acid treatment effectively delayed firmness decline and increase in PLW, TSS and lycopene content. The treated fruits maintained the integrity of cell wall composition by delay in increase in activities of cell wall‐degrading enzymes (pectin methylesterase, polygalacturonase and cellulose) and cell wall components (cellulose, hemicellulose, lignin and pectin) decline. Moreover, salicylic acid treatments significantly suppress expression level of ethylene‐producing genes ( ACO1 and ACS2 ) and inhibited ethylene production during storage. Overall, the salicylic acid‐induced delay in the ripening process occurs via the strong inhibition of ethylene biosynthesis, lowered cell wall‐degrading enzyme activities and slowed cell wall degradation.