Evaluation of the Potential to Extend the Harvest Period of ‘Gala’ and ‘Golden Delicious’ Apples by Preharvest 1-MCP Treatment

The duration of the effective harvest period is of great interest among growers. Longer periods enable better workload and optimization of operations. Decisions are typically made based on fruit drop and firmness. Preharvest spray treatment of Harvista™ (1-methylcyclopropene; AgroFresh Inc., Philadelphia, PA, USA) was applied to ‘Gala’ and ‘Golden Delicious’ apples to delay maturation. Apples were harvested 7–21 days and 7–26 days after treatment for ‘Golden Delicious’ and ‘Gala’, respectively. Fruit drop, fruit diameter, ethylene production, firmness, soluble solids content (SSC), starch index and color were measured. Measurements were performed at harvest and after 7 days’ shelf life. Quality parameters suggest different extensions to the harvest period. The SSC models showed that a 5% increase can occur with longer than 6 days delay in harvest. The starch index models showed 9.6 days’ delay for ‘Gala’ and 6.3 days’ delay for ‘Golden Delicious’ apples. The accurate measurement of firmness and the performance of its models suggest that the harvest period can be extended by 12 days for ‘Gala’ and 11 days for ‘Golden Delicious’ apples, when fruit are subjected to preharvest spray treatment.