Project Number: 5350-43000-005-04
Project Type: Trust

Start Date: May 01, 2006
End Date: Apr 30, 2009

Objective:
Characterize apple fruit production of nitric oxide during fruit development and ripening. Characterize apple fruit response to exogenous nitric oxide at harvest and during storage. Characterize apple fruit response to activators/inhibitors of nitric oxide metabolism.

Approach:
Apple fruit will be harvested sequentially starting at least 2 weeks prior to anticipated commercial harvest. Fruit will be placed into sealed vessels (typically glass jars) from which gas samples will be removed and analyzed. For maturity studies, fruit will also be analyzed for ethylene production, starch clearing, firmness and other quality attributes to establish relationships between known indices of maturity and nitric oxide. Similar studies will be conducted with fruit previously treated with 1-MCP, ethylene, stored in air or CA, or during ripening after removal from storage. Experiments will be conducted where fruit is exposed to nitric oxide over a range of concentrations, durations, temperatures, and O2 concentrations. Treated fruit will then be held in cold storage in air or CA with cultivar specific 02 and CO2 concentrations. Nitric oxide applications will be made at harvest and/or during storage to evaluate optimum treatment timing and duration of effects. Treatment effects will be established by analysis of fruit ethylene production, respiration, incidence of physiological disorders and fruit quality. Studies will also be conducted to evalute whether existing components of the apple postharvest system (temperature, 02, CO2, ethylene, 1-MCP, AVG) impact fruit NO production. Docments Trust with WA Tree Fruit Research Commission. Log. 31335. Formerly 5350-43000-004-15T 10/2006.