Preventing ripening blockage in 1-MCP treated ‘Abate Fetel’ pears by storage temperature management

Many cultivars of European pears, treated with 1-methylcyclopropene (1-MCP), undergo a blockage of the ripening process that does not resume during shelf life. We evaluated the possibility to use different storage temperatures to prevent ripening blockage by 1-MCP and at the same time inhibit superficial scald. Early and optimal harvested ‘Abate Fetel’ pears were treated with 320 nl L-1 1-MCP for 24 h at 2°C. Subsequently the fruits were stored in air at -1 and 1°C for 17 and 34 weeks, respectively. All fruits treated with 1-MCP, depending on storage type and length, had lower ethylene production, compared with untreated controls. While treated fruits kept at 1°C were still firm at the end of storage and ripened normally to eating quality, softening and peel yellowing were prevented in fruit kept at -1°C. Superficial scald damaged the fruits kept at -1°C but not those stored at 1°C. 1-MCP treatment fully prevented scald. During storage the concentration of α-farnesene increased up to 17 weeks while conjugated trienols reached a peak after 34 weeks with large differences between -1 and 1°C. 1-MCP effectively reduced conjugated trienol accumulation at both storage temperatures. Results indicate the importance of raising the storage temperature from -1 to 1°C for reducing susceptibility to superficial scald, to avoid the ripening blockage by 1-MCP mainly in early picked fruit.