Effect of brassinolide on chilling injury of green bell pepper in storage

The effect of brassinolide (BR) on chilling injury of green bell pepper fruit was investigated. BR at the concentrations of 5, 10 and 15 μM effectively reduced chilling injury of pepper fruit during 18-day storage at 3 °C, and BR at 15 μM showed the best effect. BR treatment also reduced the electrolyte leakage and malondialdehyde content of pepper fruit during storage. Results of physiological response in pepper fruit showed that BR induced the activity of antioxidant enzymes including catalase, peroxidase, ascorbate peroxidase and glutathione reductase. These results indicate that the elicitation of an antioxidant response in pepper fruit by BR may be associated with chilling injury alleviation. Moreover, BR maintained the pepper quality by delaying the decrease of chlorophyll content and l-ascorbic acid content. The present study is the first evidence that BR enhance vegetable tolerance to cold stress and therefore vegetable quality.

► Brassinolide (BR) alleviates chilling injury of green bell pepper fruit at 3 °C. ► BR induces the activity of antioxidant enzymes of pepper fruit. ► BR improves pepper fruit quality at 3 °C.