DISTRIBUTION OF PHOTOSYNTHATES AFTER 14CO2 ASSIMILATION BY STEMS, LEAVES, AND PODS OF RAPE PLANTS

Abstract

Rape (Brassica napus L. cv. Zephyr) plants were allowed to assimilate ¹⁴CO₂ through lower and upper stem internodes, leaves, and pods. Lower stem internodes exported few ¹⁴C-labelled assimilates. Lower leaves exported assimilates to the roots, whereas upper stems and leaves exported primarily to seeds and pods. Pods did not export labelled assimilates to other pods or plant parts but labelled photosynthate was detected in seed of the treated pod. The older the pod was, the greater the amount of radioactivity detected in the seed. Pods were also sinks for labelled assimilates from upper stem internodes and leaves.