Quality attributes of cantaloupe (Cucumis melo L.) fruit under pre-harvest and post-harvest treatment with methyl jasmonate and salicylic acid

Abstract

Cantaloupe (Cucumis melo L.) is one of the most delicious fruits popularly cultivated in tropical regions due to its sweet-juicy taste, attractive flavor and bioactive composition. Extending cantaloupe shelf-life during handling and distribution is very necessary to upgrade its commercial value. Methyl jasmonate (MJeA) and salicylic acid (SA) are bio-regulators widely applied on either pre- or post-harvest to extend the shelf life and maintain fruit quality during storage. In this investigation, the possibility of both preharvest (7 days before harvesting) via spraying and post-harvest (immediately after harvesting) evaluated by dipping on cantaloupe fruit by either MJeA (3 mM) or SA (3 mM) separately; in combination with MJeA/SA (1.5/1.5 mM/mM) for 30 s. These fruits were kept at 24±0.5 oC for 28 days of storage. In 7 day-interval, fruits were sampled to verify firmness, weight loss, decay rate, total soluble solid, carotenoid, vitamin C, total phenolic content, total flavonoid content. Results revealed that there was a significant difference in quality attributes between the treated samples and the control ones. However, there was no significant difference in quality attributes on either pre-harvest or post-harvest treatments by MeJA and SA reagents. Incorporation of MJeA/SA (1.5/1.5 mM/mM) by either pre-harvest or post-harvest maintained the most firmness (52.10±0.11 N or 52.37±0.08 N), total soluble solid (18.08±0.05 oBrix or 18.15±0.04 oBrix), carotenoid (46.97±0.02 µg/100 g or 47.10±0.03 µg/100 g), vitamin C (26.04±0.02 mg/100 g or 26.17±0.02 mg/100 g), total phenolic content (117.86±0.05 mg GAE/100 g or 119.75±0.09 mg GAE/100 g), total flavonoid content (84.04±0.02 mg QE/100 g or 84.20±0.02 mg QE/100 g) as well as the least weight loss (3.74±0.01% or 3.66±0.03%) and decay rate (1.42±0.01% or 1.26±0.03%) at the end of 28 days of storage. The synergistic effect of MeJA and SA would be a promising alternative to preserve cantaloupe fruit quality with a long shelf life.