1-Methylcyclopropene reduces chilling injury of harvested okra (Hibiscus esculentus L.) pods

Experiments were conducted to investigate the effects of 1-methylcyclopropene (1-MCP) on chilling injury disorders and quality maintenance of harvested okra (Hibiscus esculentus L.) fruit during storage at low temperature. Okra fruit were treated with 1 or 5 μl L−1 1-MCP for 16 h before storage for 18 d at 7 °C. Application of 1-MCP significantly alleviated the development of chilling injury disorders such as browning and pitting in okra pods in a concentration-dependent pattern, which was associated with lower membrane permeability and lipid peroxidation. In addition, 1-MCP treatment inhibited the decreases in color parameters (hue angle, lightness and chroma) and chlorophyll degradation, indicating that the bright green color in 1-MCP-treated fruit was well maintained. Furthermore, 1-MCP reduced the chilling-induced decline in variable:maximal chlorophyll fluorescence (Fv/Fm), an indicator of stress injury in plant tissues. Moreover, significantly lower respiration rate in 1-MCP-treated okra was also observed than in control fruit. Overall, 1-MCP treatment showed great potential to reduce the development of chilling injury disorders and maintain fruit quality, which may be a promising technique to extend the storage life of okra pods at low temperature.

► Responses of okra stored at low temperature to 1-methylcyclopropene (1-MCP) were investigated.
► 1-MCP significantly inhibited chilling injury disorders of okra pods during cold storage.
► The light green color and chloroplast activity of okra pod was well maintained by 1-MCP.
► 1-MCP treatment could provide a potential way to extend storage life of okra pod at low temperature.