Abscisic acid alleviates chilling injury in cold-stored peach fruit by regulating the metabolism of sucrose

Peach (Prunus persica (L.) Batsch) fruit are stored cold to extend postharvest life but are susceptible to chilling injury, which is often manifested as browning of the internal flesh and failure to ripen normally. Peach fruit stored at 0 °C developed severe internal browning, beginning after approximately 14 d Fruit treated with 100 μmol L−1 abscisic acid (ABA) prior to storage exhibited much reduced internal flesh browning, and this was correlated with increased amounts of soluble sugars. The sucrose contents in ABA-treated fruit increased or were maintained for a longer period, whereas in controls sucrose amounts declined. ABA treatment increased the activities of sucrose synthase and sucrose phosphate synthase, and decreased the activity of acid invertase. Corresponding changes in the abundances of transcripts encoding these activities were also observed. The findings show that a treatment with ABA reduces chilling injury in peach at least in part by regulating the metabolism of sucrose.