Seasonal Changes in Total Free Sugar Content of Field Cocoa Plants

Abstract

AbstractAs part of a study of factors affecting the vegetative and reproductive characteristics of cocoa, Theobroma cacao L., (viz. leaf flushing, flowering, cherelle wilt, pod setting and pod growth), seasonal changes in total free sugar levels of the bark and wood of field cocoa trees growing under medium shade provided by Gliricidia sepium Steud. trees were studied over a period of 13 months. On dry weight basis, sugar content of the bark (13 to 63 mg/g) was higher than that of the wood (9 to 40 mg/g). Free sugar content was significantly correlated with sunshine hours for the whole period, except October‐November 1975, and March 1976 when pod load, and flowering and leaf flushing respectively, caused considerable reduction in free sugar levels. The peaks of flowering and flushing coincided with those of sunshine hours and free sugar levels. The results, analysed in terms of the prevailing microclimatic conditions, suggest that light is a limiting factor for photsynthesis of shaded cocoa and that the reported stimulation of flowering and leaf flushing, which accompany shade removal, may be attributed to increased sugar status of the trees due to increased photosynthetic activity.