Influence of 1-methylcyclopropene on Ripening, Storage Life, and Volatile Production by d'Anjou cv. Pear Fruit

d'Anjou cv. pear fruit (Pyrus communis L.) exposed at harvest to 0, 0.42, 4.2, or 42 micromol m(-)(3) 1-methylcyclopropene (1-MCP) for 12 h at 20 degrees C were stored at 1 degrees C for up to 8 months. After storage, half of the fruit was continuously exposed to ethylene (0.45 or 4-18 mmol m(-)(3)) for 7 days at 20 degrees C. All fruit treated with 1-MCP had lower respiration and ethylene production compared to untreated controls. Fruit quality changes were delayed following 1-MCP treatment, as was development of superficial scald and peel yellowing. The duration of 1-MCP-induced responses was dependent on 1-MCP treatment concentration. When 1-MCP-treated fruit began to ripen, softening and production of volatile compounds proceeded similar to that of untreated fruit. Post-storage ethylene exposure did not consistently stimulate ripening of fruit previously treated with 1-MCP. Efficacy of ethylene treatment depended on 1-MCP concentration and storage duration.