Postharvest senescence of fresh lotus pods and seeds is delayed by treatment with 1‐methylcyclopropene

Abstract

AbsractFresh lotus pods were treated with 1‐methylcyclopropene (1‐MCP) at a concentration of 0.5 μL L−1 for 24 h at 25°C and then stored at 25°C for 8 days. First, their quality and physiological changes during storage were measured in terms of visual appearance, respiration rate, firmness, and the contents of sugars, protein, total phenolics and malondialdehyde (MDA). The results showed that the 1‐MCP treatment reduced the browning of fresh lotus pods, and inhibited the respiration rate during storage. In addition, the 1‐MCP treatment alleviated changes in firmness, delayed starch and protein degradation, and the accumulation of reducing sugars and total sugars in lotus seeds, preserving the good taste of lotus seeds. Moreover, the 1‐MCP treatment alleviated the increase of MDA and effectively inhibited the decrease in total phenolics in lotus seeds during days 6 to 8 of storage. Meanwhile, the results of antioxidant capacity in lotus seeds indicated that 1‐MCP not only sustained a higher level of 1,1‐diphenyl‐2‐picrylhydrazyl free radical scavenging activity, but also increased the activities of superoxide dismutase, catalase and peroxidase throughout the storage period. However, the 1‐MCP treatment reduced polyphenol oxidase activity in seeds relative to the control. Moreover, we found that the adenosine triphosphate content and energy charge during the last 4 days of storage were higher in 1‐MCP‐treated seeds than in the control. These results indicated that the use of 0.5 μL L−1 1‐MCP provided an effective method, via multiple lines of evidence, to delay the postharvest senescence of fresh lotus pods and seeds.