Effects of exogenous polyamine and ultrasound treatment to improve peach storability

Peach (Prunus persica [L.] Batsch) is a perishable product and its storage period may be extended by using different postharvest methods. For this purpose, peaches harvested at the commercial ripening stage were treated with individual and combined effects of putrescine (1 mM) and ultrasonic treatment (32 kHz for 10 min); postharvest storage quality of peach fruit was evaluated during storage at 0-1 degrees C for 28 d. Quality characteristics such as weight loss, fruit firmness, respiration rate, total sugar, total soluble solid content, titratable acidity, chilling injury, and decay rate were determined at the beginning and during the storage period at 1-wk intervals. The result showed that individual and combined effects of putrescine and ultrasonic treatment, when compared to control fruits, could increase peach fruit postharvest life by inducing resistance to different diseases and chilling injury with no noticeable effect on fruit quality attributes such as weight loss, total soluble solids, and total sugar. At the same time, a combined putrescine and ultrasound treatment was found to be more effective than other treatments in decreasing respiration rate and maintaining firmness and acidity. Peach storability could be extended with a combined putrescine and ultrasound treatment because it delays the ripening processes.