Project Number: 5350-43000-005-05
Project Type: Trust

Start Date: Oct 01, 2006
End Date: May 30, 2011

Objective:
The role of ethylene action in preharvest development of 'Barltett' pear and 'Braeburn' apple fruit will be examined using exogenous chemicals that stimulate (ethephon) or reduce (1-methylcyclopropene) ethylene production and activity, respectively. Fruit will be sampled over a 1 to 2 month period overlaping the onset into the ripening phase of development, and samples will be evaluated at harvest and after cold storage in air or a controlled stmosphere. Studies will be executed on apple trees in the Wenatchee, Washington area and fruit will be evaluated at the ARS Tree Fruit Research Laboratory in Wenatchee.

Approach:
Materials to stimulate (ethephon) or reduce (1-methylcyclopropene) ethylene production and activity, respectively, will be applied to apple and pear trees at various rates and selected intervals prior to harvest. Physiological (volatile production, respiration, ethylene-related gene expression) and horticultural (color, weight, firmness, acidity, sugar content) indicators of fruit development will be determined using fruit sampled at various intervals after these spray applications. Fruit will also be held in cold storage for several months prior to similar evaluations to identify postharvest impacts from these field treatments. All evaluations will be conducted at the Tree Fruit Research Laboratory in Wenatchee. Documents Trust with Agrofresh. Log 31336. Formerly 5350-43000-004-16T (10/06).