Objective:
The project aims to identify roles of ethylene action in development of apple and pear fruit physiological disorders. Research will focus on identification of key physiological events that lead to development of internal and external CO2 injury (apple) and chilling injury (apple and pear).

Approach:
Materials to stimulate (ethephon) or reduce (1-methylcyclopropene) ethylene production and activity, respectively, will be applied to apple and pear fruit at various rates and selected intervals prior to and/or after harvest. Physiological (volatile production, respiration, ethylene-related metabolites) and horticultural (color, weight, firmness, acidity,sugar content) indicators of fruit development will be determined using fruit sampled at various intervals at harvest and after storage. All evaluations will be conducted at the Tree Fruit Research Laboratory in Wenatchee.