Regreening of Valencia Orange as Influenced by Potassium Gibberellate

Abstract

Potassium gibberellate (KGA) was applied to Valencia orange fruit which were predominantly orange in color. Analyses of rind pigments were made for 19 weeks after treatment. Treated fruit contained higher levels of chlorophyll a and chlorophyll b in apical, equatorial, and basal (stem end) regions of the rind than did untreated fruit. Treatment increased protochlorophyll in the basal region. Chlorophyll a accumulation in treated fruit was enhanced proportionally more than chlorophyll b. In treated and untreated fruit, chlorophyll a and b were higher in basal than in apical regions. The mechanism of regreening, already present in the fruit, appears to be favored by gibberellin.