Preharvest 1-Methylcyclopropene Treatment Reduces Soft Scald in 'Honeycrisp' Apples during Storage

The main objective of this study was to investigate the effectiveness of preharvest 1-methylcyclopropene (1-MCP) treatment on the development of soft scald in `Honeycrisp' apples. In addition, the effects of preharvest 1-MCP on fruit quality at harvest and after storage were examined. For two consecutive years of study, 'Honeycrisp' trees were sprayed preharvest with 1-MCP and fruit were harvested twice during each year. Preharvest 1-MCP treatments had little consistent effect on fruit maturity at the time of harvest. In both years of study, preharvest 1-MCP reduced the incidence of soft scald in 'Honeycrisp' apples after air storage at 0 or 3 degrees C for 5 or 6 months. Soggy breakdown developed only in the second year of study and high incidences were reduced by preharvest 1-MCP treatments. Preharvest 1-MCP often reduced flesh firmness loss in `Honeycrisp' during storage, especially during the second year of study, and with 1-MCP application closer to harvest. Malic acid content was often higher in apples with the preharvest 1-MCP spray closer to harvest. Overall, the most important benefit of preharvest 1-MCP treatments on `Honeycrisp' apples was the reduction in soft scald development. Due to the high potential for substantial fruit losses from this disorder, the use of preharvest 1-MCP sprays on `Honeycrisp' apples could be very advantageous.