Abstract: The effect of 2,4-epibrassionolide (EBR) treatment on Rhizopus rot and energy metabolism in postharvest peach fruit (Prunus persica (L.) Batsch cv Baifeng) was investigated. Peach fruit were treated with EBR solutions of different concentrations (0, 1, 5 and 10 μmol/L) for 10 min, then inoculated with Rhizopus stolonifer, and finally stored at (20 ± 1) ℃ for 60 hours. The results showed that treatment with EBR at 5 μmol/L was the most effective in suppressing the increase in lesion diameter and disease incidence in peach fruit (P < 0.05) and maintaining good quality during storage. Compared with the control group with the inoculation of Rhizopus stolonifer alone, EBR treatment could increase the activity of Ca2+-ATPase, H+-ATPase, succinate dehydrogenase and cytochrome oxidase, delay the decrease in adenosine triphosphate and adenosine diphosphate contents, and inhibit the increase in adenosine monophosphate content, thus maintaining high energy level of peach fruit. Correlation analysis showed that disease incidence and energy level were significantly negatively correlated in the control (r = ?0.939, P < 0.01) and EBR treatment groups (r = ?0.962, P < 0.01). These results suggested that EBR treatment could inhibit Rhizopus rot of postharvest peach fruit, which may be related to maintenance of high energy level.

Key words: peach fruit, 2,4-epibrassionolide, Rhizopus rot, energy metabolism