Influence of Time and Concentration of 1-MCP Application on the Shelf Life of Pear 'La France' Fruit

La France∑ pear (Pyrus communis L.) fruit were ex posed to chilling temperature (-1 °C) for a week to induce ethylene biosynthesis before they were transferred to 20 °C to allow rip en ing. On 1, 4, or 7 days after the transfer to room temperature, fruit were treated with 20 µL·L-1 1-MCP for 12 hours. The 1-MCP treatments suppressed ethylene and carbon dioxide production significantly and slowed fruit softening. The shelf life pe ri od of fruit with desirable firmness treated with 1-MCP on day 4 was twice that of untreated fruit, with firmness of 1-MCP treated fruit on day 1 being higher than desirable while that of fruit treated on day 7 was lower than desirable. To determine the optimum 1-MCP con cen tra tion for treatment, fruit were exposed to 0.01 to 100 µL·L-1 1-MCP 3 days after the transfer to 20 °C. The fruit treated with 1 µL·L-1 1-MCP and less ripened similarly to untreated fruit, having a shelf life of a week. 1-MCP treatments of 10 and 100 µL·L-1 inhibited ethylene and carbon dioxide production, and de layed fruit softening and occur- rence of se nes cent break down. The flesh firmness of these fruit maintained suit able eating quality for more than 3 weeks. Our results indicate that 1-MCP treat ment of 10 µL·L-1 at 20 °C 3 to 4 days after initiation of ripening can extend the shelf life of 'La France∑ pear fruit. Chemical name used: 1-methylcyclopropene (1-MCP).