Studies on the Mechanism of Ethylene Action for Fruits Ripening I

Abstract

While ethylene effect on fruit ripening has received much attention, the mechanism of the effect is not yet clear. As a research of the series of the study concerning the mechanism of ethylene effect, this paper reports the problem of ethylene movement in a banana fruit which was treated at a part of the fruit. The concentration of ethylene applied was 80-100ppm throughout the experiment.
When mature-green bananas were treated partly at the central part of peel surface with ethylene, the ripening of the fruit began from the treated part and developed gradually toward untreated part, showing the degreening of peel color and the increase of sugar content in pulp.
Mature-green bananas treated at the apical side of fruits evolved a considerable amount of ethylene from the untreated stem side within 3 hours after initiation of ethylene application. Then, carbon dioxide evolution from the parts of both sides began increase between 8-14 hours after treatment. Thus, it seems that the movement of ethylene gas or of its effect in a fruit is considerably rapid. When banana fruits were girdled at the center of fruits and treated with ethylene at one side, ethylene evolution from the untreated other side was markedly less than that of ungirdled fruits, indicating that peel would play an important role in movement of ethylene gas or of its effect in fruit.
Treatment on whole fruits with ethylene for 24 hours stimulated fruit _??_ipening obviously, but the treatment for 2 and 6 hours did not show any effect.