2002 Volume 28 Issue 5 Pages 235-241
Involvement of ethylene on changes in gas metabolism and fruit color of pineapple fruit after harvest was studied, using 1-methylcyclopropene (1-MCP), an ethylene action inhibitor. Rates of respiration and ethylene production of fruit harvested at mature green stage continued increasing during storage, showing the pattern increasing towards the end of storage, but the maximum ethylene production rate was less than 1 nl g-1 h-1. 1-MCP decreased respiration and temporarily increased ethylene production from the fruit. Propylene, which transiently increased respiration, did not stimulate ethylene production. When whole fruit was separated into fruit part and crown, the pattern of gas metabolism in whole fruit was completely dependent on fruit part, not on crown. Treatment of immature, mature green and ripe fruits with 1-MCP for several times resulted in temporal stimulation of ethylene production immediately after each treatment, irrespective of harvest maturity. Respiration and ethylene production, which increased on the tree as fruit developed, continued increasing after harvest. Fruit color progressed in all fruits harvested at three different maturity, but was delayed by 1-MCP, in which the younger the fruit, the more prominent was the effect of 1-MCP on inhibition of color change. These results indicated that ethylene production in harvested pineapple fruit is controlled by negative feedback regulation (autoinhibition), and that ethylene is involved in fruit color change. Pineapple fruit at least partially perform postharvest ripening since gas metabolism and fruit color in harvested fruits changed just as on-tree fruit.