Post-harvest Quality Changes in Fresh Lotus Seed Treated with Methyl Jasmonate.

To investigate the effects of exogenous methyl jasmonate (MeJA) on the post-harvest quality of fresh lotus seed, MeJA (100 µmol/L) was used to soak the fresh lotus seed with water as the control. The changes in the color difference (L*, a*, b*), nutrient content (starch, soluble sugar), and other physiological and biochemical indexes (weight loss rate, total phenol content, malondialdehyde content, hydrogen peroxide content, polyphenol oxidase activity, superoxide dismutase activity, catalase activity and peroxidase activity) were compared every 2 days. The results showed that compared with the control group, the MeJA treatment effectively maintained the postharvest color of fresh lotus seed. After 8 days of storage, compared with the control group, the MeJA-treated group had a lower weight loss rate (decreased by 33.84%), and higher starch content (increased by 38.34 mg/g), higher soluble sugar content (increased by 70.58 mg/g), along with a reduced total phenol content, suppressed PPO activity, MDA content and H₂O₂ accumulation, and enhanced SOD, CAT and POD activities. The above results revealed that the MeJA treatment could delay the post-harvest quality decline of fresh lotus seed through reducing material consumption, maintaining starch and soluble sugar contents, reducing the oxidation of phenols, improving the activities of antioxidant enzymes, as well as maintaining the cell membrane integrity, thereby prolonging their shelf life. [ABSTRACT FROM AUTHOR]