1980 Volume 49 Issue 3 Pages 421-428
Mechanisms which serve to suppress the ripening of fruits following the treatment with high concentrations of CO2 were investigated. When tomato fruit was treated with 100% CO2 for one day, CO2 exhaust remained at high level relative to nontreated fruit for several days after treatment. This phenomenon was also observed in banana and pear fruits. The ethylene production of tomato and banana fruits after treatment was also higher than that of non-treated fruits. However, the ethylene production of pear fruit decreased somewhat as the period of treatment became longer. When tomato fruit was treated with 100% CO2 for one day, the activities of enzymes related to respiratory metabolism changed remarkably during and after the treatment: glucose-6-phosphate dehydrogenase and malic enzyme were not activated following the ripening of fruit; phosphofructokinase showed a marked fluctuation after the treatment; alcohol dehydrogenase was activated during the treatment, and also was at high activity level after the treatment; and succinate oxidation in mitochondria was lowered during the treatment, but activated after the treatment. In addition, KCN inhibition of succinate oxidation decreased, and the respiratory control ratio of mitochondria was lowered for several days after the treatment; these results indicate the development of CN-resistant respiration through out the period.
