Trehalose maintains the quality of Malus domestica by mediating sucrose and respiratory metabolism

Quality breakdown and decay are the main factors that cause economic losses of fruit and vegetable during storage. Apple fruit (cv. Golden Delicious) were dipped in 1.5 g L−1 trehalose to investigate the changes of quality parameters, activity and gene expression of key enzyme in sucrose and respiratory metabolism. Results showed that trehalose treatment suppressed weight loss and respiratory rate, maintained soluble solid content and flesh firmness in apples. Moreover, trehalose suppressed neutral invertase (NI) and sucrose synthase cleavage (SS-c), cytochrome oxidase (CCO) and succinate dehydrogenase (SDH), glucose phosphate isomerase activities and MdNI, MdSS, MdSDH and MdCCO expressions in apple fruit. Meanwhile, trehalose increased the activities of sucrose phosphate synthase (SPS), sucrose synthase synthesis (SS-s) and glucose 6-phosphate dehydrogenase (G6PDH), and MdSPS, MdG6PDH and MdPFK expressions in apples. These results propose that trehalose treatment maintains storage quality of apples by regulating sucrose and respiratory metabolism during storage.