Sodium bicarbonate salts for the control of postharvest black rot disease in yellow pitahaya (Selenicereus megalanthus)

Black rot caused by Alternaria alternata in yellow pitahaya (Selenicereus megalanthus) is a significant postharvest disease that is difficult to control. Sodium bicarbonate (SBC) treatments were tested in order to incorporate them into an integrated disease management program and to reduce postharvest use of synthetic fungicide. The control of black rot on fruit treated with 298 mM (2.5%) sodium bicarbonate (SBC) was superior to that resulting from other SBC treatments on fruit examined after 21 d at 12 °C plus 5 d of shelf-life at 20 °C. Treatment with 298 mM reduced weight loss, retained color and firmness, slowed changes in total soluble solids, titratable acid content, and pH of yellow pitahaya during storage and shelf-life. After storage, the general appearance of fruit treated with 298 mM SBC was significantly better than that of those treated with imazalil or non-treated fruit. Treatment with 298 mM SBC is potentially useful in controlling postharvest black rot in yellow pitahaya without harming its sensory quality.