The Regulated Effect of Ethylene and 1-MCP on theLignification of Postharvest Green Asparagus(Asparagus Officinalis L.)

摘要

Effects of ethylene and ethylene perception inhibitor 1-methylcyclopropene (1-MCP)on phenol, lignin, oxygen contents and enzyme activities involved in lignification, phenylalanineammonia-lyase (PAL), polyphenol oxidase (PPO), cinnamyl alcohol dehydrogenase (CAD),peroxidase (POD )in harvested asparagus cv. Mary Washington 500 spears were evaluated.Lignin, phenol or active oxygen content was enhanced by ethylene and reduced by 1-MCPtreatment significantly. Ethylene treatment increased the activity of PPO, CAD and POD.however 1-MCP treatment significantly increased the activity of PPO and CAD, and delayed theacticvity of POD. The lignin accumulation in postharvest green asparagus can be declinedsignificantly by suppressed POD activity and active oxygen content. Exogenous ethylene or 1-MCP may regulate the deposition of lignin through up-regulation of enzyme activity and activeoxygen production. Besides of enzymic toughening, a free radical phenol coupling mechanismis suggested as being responsible for lignification of asparagus.