Postharvest Methyl Jasmonate Alleviates Chilling Injury and Maintains Quality of ‘Kinnow’ (Citrus Nobilis Lour x C. deliciosa Tenora) Fruits Under Differential Storage Temperature

Abstract

Application of novel generally recognized as safe (GRAS) chemicals may help in preserving the health promoting compounds and esthetic value of the ‘Kinnow’ (Citrus nobilis Lour x C. deliciosa Tenora) fruits. The aim of this study was to evaluate the effect of exogenously applied methyl jasmonate (MeJA) at differential storage temperatures on the postharvest quality of ‘Kinnow’ mandarin (Citrus nobilis Lour x C. deliciosa Tenora) fruits. Physiologically mature freshly harvested fruits were treated with the different concentrations of MeJA, i.e., 0.1 mM, 0.3 mM, 0.5 mM, 0.7 mM and control for 5 min and air dried for 10 min. The treated fruits were stored consecutively at two different temperatures of 2 °C for 20 days and at 6 °C for 20 days at 85–95% relative humidity. Results showed that MeJA treated fruits maintained better quality of ‘Kinnow’ mandarin (Citrus nobilis Lour x C. deliciosa Tenora) fruits than control during the entire storage period. Fruits treated with MeJA (0.5 mM) and stored at differential temperatures significantly delayed the loss in fruit weight, maintained firmness, maintained higher total soluble solids (TSS), total phenols content (TPC), ascorbic acid (AA), antioxidant activity (AOX) and lower titratable acidity (TA) content with zero chilling injury (CI) under a cold storage period of 40 days. Also, MeJA (0.5 mM) treatment showed higher overall sensory attributes, making the fruits more acceptable to consumers after 40 days of storage. In conclusion, postharvest application of MeJA (0.5 mM) at differential temperatures proved an effective and safe strategy to enhance the quality and shelf-life of ‘Kinnow’ (Citrus nobilis Lour x C. deliciosa Tenora) fruits.