Hydrogen peroxide treatment promotes early ripening of Kyoho grape

BACKGROUND AND AIMS: Reactive oxygen species are involved in fruit ripening. Here, we investigated the role of hydrogen peroxide (H₂O₂) in promoting grape (Vitis vinifera L.) berry ripening. METHODS AND RESULTS: Solutions of 100, 300 and 500 mmol/L H₂O₂ were sprayed on Kyoho bunches 25 days post anthesis (dpa). All treatments promoted early ripening of berries, although the 300 mmol/L treatment was the most effective; at this concentration, Kyoho berries ripened 20 days earlier than the Control. Ripening‐related physiological indexes, such as berry diameter and firmness, anthocyanin, sucrose and malonaldehyde concentration, and catalase, cellulase and polygalacturonase activity, were similar for the H₂O₂‐treated and Control berries. The TSS concentration of berries treated with 300 mmol/L H₂O₂ was significantly higher than that of Control berries throughout the experiment. Superoxide dismutase activity in H₂O₂‐treated berries was significantly higher than that in Control berries at 35 and 70 dpa. All H₂O₂ treatments enhanced the ascorbic acid concentration of berries. CONCLUSIONS: Exogenously applied H₂O₂ promotes the early ripening of Kyoho berries. SIGNIFICANCE OF THE STUDY: This study provides a simple, efficient, safe, economical and environmentally friendly medium to promote early ripening of grape berries.