Low-temperature conditioning enhances chilling tolerance and reduces damage in cold-stored eggplant (Solanum melongena L.) fruit

Eggplant fruit are vulnerable to chilling injury (CI) after prolonged storage at temperatures below 12 °C. Here, we tested the effect of low-temperature conditioning (LTC) on chilling tolerance in eggplant fruit, in which fruit were stored at 13 °C for 2 d, and then held at 4 °C. Our results indicated that LTC maintained the appearance of eggplant fruit, and retarded the development of CI; the effect of LTC was characterized by inhibited sepal browning, and reduced loss of anthocyanins, and total phenolic compounds. The activity and relative gene expression of peroxidase (POD) and catalase (CAT) were increased by LTC, whereas the activity and relative gene expression of polyphenol oxidase (PPO) was reduced. In addition, the level of malondialdehyde (MDA) was significantly reduced. Our results suggest that LTC induces a range of physiological and molecular responses that enhance chilling tolerance in eggplant fruit.