Optimization of the Alternatives to Control Superficial Scald in ‘beurré D’anjou’ Pear Avoiding Detrimental Effects on Fruit Quality

In a previous work it was determined that dynamic controlled atmosphere (DCA) and 0.3 mu L L-1 1-methylcyclopropene were efficient to control superficial scald in 'Beurre d'Anjou' pear, but with detrimental effects on quality because of the development of internal cavities (DCA) and ripening impairment (1-MCP), respectively. In this work, these strategies were optimized reducing the CO2 concentrations for DCA storage and 1-MCP dose used. Pears were harvested at optimal maturity, treated with 0 (control) or 0.15 mu L L-1 1-MCP (1-MCP150) and stored for 240 days in regular air or in DCA with less than 0.4% CO2 (DCA). Combined strategies (DCA+1-MCP) were also tested. Changes in fruit maturity, ethylene, a-farnesene, conjugated trienols levels, and physiological disorders were monitored monthly. All the storage strategies reduced ethylene production and scald incidence compared to the control. At the end of the storage (240 days), scald affected 100% of control fruit, 7% of DCA and 10% of 1-MCP150 fruit. Only DCA+1-MCP150 treatment completely inhibited superficial scald but fruit did not reach eating quality. DCA applied alone or combined with 1-MCP led to high incidence of cavities already after 2 months of storage. According to our results 1-MCP150 treatment appeared to be the best strategy to control superficial scald in 'Beurre d'Anjou' pear without detrimental effects on fruit quality.