Involvement of Ethylene in Chlorophyll Degradation in Peel of Citrus Fruits

Publisher Website
Google Scholar
Abstract
The effect of ethylene on chlorophyll degradation in the peel of Robinson tangerine (X Citrus reticulata Blanco) and calamondin (X Citrofortunella mitis [Blanco] Ingram and Moore) fruits was studied. The chlorophyll degrading system in the peel of these 2 citrus species was not self-sustaining but required ethylene to function. Chlorophyll degradation ceased immediately when fruit were removed from ethylene and held in ethylene-free air at 0.2 atmospheric pressure. At atmospheric pressure, chlorophyll degradation continued for 24 h in the absence of exogenous ethylene. Although chlorophyllase levels were negatively correlated with chlorophyll content in the peel (r = -0.981; P < 0.01), the level of chlorophyllase activity did not change when fruit were removed from ethylene, even though chlorophyll degradation had stopped. Evidently, ethylene is necessary for chlorophyll degradation in the 2 spp. of citrus studied, but its primary role is not solely for the induction of chlorophyllase activity.