Firmness Retention, and Prevention of Coreline Browning and Senescence in `Macoun' Apples with 1-Methylcyclopropene

1-Methylcyclopropene (1-MCP) maintained firmness of `Macoun' apple ( Malus × domestica Borkh.) above 50 N after 90 to 100 days regular air storage when harvested at a starch index of 2.7 to 3.5, and after 50 days when harvested at a starch index past 4.0. Softening of `Macoun' was slowed by 1-MCP in both preclimacteric and climacteric fruit, but for a shorter duration in climacteric fruit. 1-MCP reduced but did not eliminate the occurrence of senescent breakdown. The effect of 1-MCP on coreline browning was inconsistent, reducing its occurrence in 2002 and 2003, but increasing its occurrence in 2001 when fruit were harvested at an advanced maturity.