Gross, J., Institut für Obstbau und Gemüsebau, Bonn, Germany
Bazak, H., Department of Fruit and Vegetable Storage, Agricultural Research Organization, Bet Dagan, Israel
Blumenfeld, A., Department of Subtropical Fruits, Agricultural Research Organization, Bet Dagan, Israel
Ben-Arie, R., Department of Fruit and Vegetable Storage, Agricultural Research Organization, Bet Dagan, Israel

Gibberellin (GA3-10-4 M) was applied on different dates to 'Triumph' persimmon trees (Diospyros kaki L.). A delaying effect of GA3 on ripening was assessed by reflected colour measurements. The delay in fruit colour development resulting from GA3 sprays was evidently due to inhibition of chlorophyll degradation and of carotenoid biosynthesis. Analysis of the carotenoid pattern by chromatographic means (TLC) at 2-week intervals permitted a precise characterization of maturation. It was found that maturity changes were accompanied by an increase in cryptoxanthin level. The delaying effect of GA3 and its duration could be exactly assessed from the determination of the cryptoxanthin content. © 1984.