BIOCHEMICAL AND PHYSIOLOGICAL ASPECTS OF LEAF DEVELOPMENT IN COCOA (THEOBROMA CACAO) I. DEVELOPMENT OF CHLOROPHYLL AND PHOTOSYNTHETIC ACTIVITY.

Periodicity of leaf origin, rapid leaf expansion and tack of significant chlorophyll synthesis in expanding leaves of cocoa (Theobroma cacao) arc unusual features of leaf development. Changes in chlorophyll content, photosynthetic activity and ribulose-1,5-diP carboxylase activity were determined during flush leaf development. Chlorophyll synthesis was found to be closely related to leaf expansion. Photosynthesis per unit area, photosynthesis per unit chlorophyll and ribulose-1,5-diP carboxylase activity all developed in parallel with chlorophyll. The significance of these findings is evaluated with regard to current concepts of photosynthetic unit development. Particular features of flush leaf development suggest that cocoa is a useful plant in which to examine the role of hormones and other factors in the control of chloroplast development. [ABSTRACT FROM AUTHOR]