غلامرضا عبدی

Physalis peruviana is a perishable fruit with a restricted shelf-life that exhibits a climacteric performance. The aim of this study was to evaluate the effect of different concentrations of melatonin treatment (0, 100, 200 and 300 µmol L−1) on extending shelf life and improving nutritional quality of P. peruviana fruit storing at 10 ± 1 °C and 90 ± 1% relative humidity for 21 days. The results showed that application of melatonin at 200 and 300 µmol L−1 was notably effective in reducing weight loss of fruit. Senescence of Physalis fruit was obviously retarded by melatonin treatment, as revealed by the firmness, total soluble solids (TSS) content, titratable acidity (TA), and TSS:TA ratio of the fruit. Melatonin treatment at 200 µmol L−1 melatonin significantly reduced the respiration rate. At 300 µmol L−1 melatonin increased the total phenolic and carotenoid, resulting in the higher antioxidant capacity and nutritional value. Melatonin significantly increased the activity of catalase, superoxide dismutase and ascorbate peroxidase enzymes during storage. The optimum concentration of melatonin for extending the postharvest life and improving the quality of Physalis fruit was 200 or 300 µmol L−1. These findings recommended that melatonin treatment may be a convenient method to extend the postharvest life and to improve nutritional quality in Physalis fruit.