Combination of nitric oxide and 1-MCP on postharvest life of the blueberry (Vaccinium spp.) fruit

Blueberries are a perishable fruit that loses its firmness and weight rapidly after harvest. High concentrations of ascorbic acid (AA) and phenolic compounds such as anthocyanins are important attributes contributing to the quality of the fruit. The aim of this work is to extend the postharvest life of three blueberries cultivars; 'Misty and 'Blue Cuinex, firm and soft cultivars respectively and 'Blue Chip with intermediate firmness. The fruit was treated separately or in combination with a nitric oxide donor, S-nitrosoglutathione (GSNO) and 1-methylcyclopropene (1-MCP) and stored at 4 degrees C for 14 d. The best treatment for 'Blue Cuinex was the combination of 1-MCP and GSNO, while 'Misty softened slower when treated with 1-MCP, and 'Blue Chip. was not affected by treatment. The 1-MCP + GSNO treatment maintained higher concentrations of AA and GSH in 'Blue Cuinex. AA concentrations declined in 'Misty but did not respond to GSNO. The combination of 1-MCP and GSNO extended the postharvest life of 'Blue Cuinex by improving the concentrations of AA and glutathione in the berries but not for 'Misty. These results demonstrate that blueberry cultivars respond differentially to 1-MCP and nitric oxide, and that the sequence of application could be used to slow fruit softening and maintain antioxidant properties.