Effect of 1-methylcyclopropene on Ripening and Superficial Scald of Japanese Pear (Pyrus pyrifolia Nakai, cv. Akemizu) Fruit at Two Temperatures

In this paper, effect of 1-methylcyclopropene (1-MCP) on 'Akemizu' pear fruit was investigated to evaluate fruit quality, respiration rate, ethylene release rate, membrane lipid peroxidation and superficial scald at room temperature (25 +/- 2 degrees C) for 20 d and at low temperature (4 +/- 1 degrees C) for 72 d. The results showed that at two temperatures, 1-MCP treatment inhibited obviously the declines of fruit quality during storage, suppressed strongly respiration rates and delayed the ethylene peaks. Furthermore, compared with the control, lipoxidase (LOX) activities and malondialdehyde (MDA) contents of 1-MCP-treated fruits appeared lower at two temperatures. The development of fruit superficial scald was alleviated to a great extent by 1-MCP or low temperature, and superficial scald could be completely inhibited under 1-MCP plus cold condition. The contents of alpha-farnesene and conjugated trienols in 1-MCP-treated or cold-treated fruits were significantly lower than in untreated fruits.