Abstract
Two experiments were conducted to test the effects of exposing Japanese persimmon 'Tonewase' fruit harvested at different maturies to varying concentrations of carbon dioxide on firmness, the evolution of ethylene and respiration. In Phase I, the fruits were exposed to ambient air and to 100% carbon dioxide for 24 hr (control) and subsequently stored at 20°C. In Exp. I, Phase I was repeated on immature fruit and the third treatment was added in which the carbon dioxide concentration was decreased from 100% to 0% after 17 hr. In Exp. II, the procedure was similar to that in Exp. I, except that more mature fruits were used and the carbon dioxide concentration was reduced from 100% to 0% after 6, 12 and 20 hr. 1. The fruits of the Japanese persimmon 'Tonewase' exposed to ambient air and those treated continuously with 100% carbon dioxide softened equally fast and ripened within 6 days. 2. Slightly immature fruits exposed to air and 100% carbon dioxide softened as in Phase I, whereas those exposed to 100% carbon dioxide for 17 hr were still firm after 2 weeks in storage. 3. Fruits exposed to air and 100% carbon dioxide softened as did those in Phase I, wheras those exposed to 100% carbon dioxide for 6, 12 and 20 hrs maintained their firmness longer during storage.
