Effects of 1-methylcyclopropene on apricot fruit quality, decay, and on physiological and biochemical metabolism during shelf-life following long-term cold storage

Mature green apricot (Prunus armeniaca L. 'Shanhuangxing') fruit were exposed to 1-methylcyclopropene (1-MCP) at 0, 0.5, 1.0, or 5.0 mu l l(-1) for 12 h, or treated with 1.0 mu l l(-1) 1-MCP for 0, 6,12, or 24 h, stored at 0 degrees C and 85 - 95% RH for 4 weeks, then transferred to a shelf-life simulation at 23 degrees C and 80 - 90% RH. The shelf-life of apricots was effectively extended for > 2 d by pre-storage 1-MCP treatment at 1.0 or 5.0 mu l l(-1) for 6 h and/or 12 h. The decline in firmness, colour change, and the incidence of fruit decay were substantially inhibited by 1-MCP at 1.0 or 5.0 mu l l(-1) for 6 h and/or 12 h during cold storage and subsequent shelf-life. Increases in soluble pectin contents and decreases in ascorbic acid contents were delayed, but the levels of total phenolic compounds and flavonoids increased in 1-MCP-treated fruit during shelf-life. 1-MCP treatment enhanced the peroxidase activity of apricot fruit for 3 d during shelf-life, but inhibited ethylene production in harvested apricot fruit. These results support an effective application of 1-MCP to maintain apricot fruit quality and to extend the time for marketing.