Fig. 6.

Quantitative representation of [U-¹⁴C] sucrose transport (expressed as % of total radioactivity exported) from a mature leaf to sink leaves, roots, stems (if present), and external medium and at the six principal growth stages of A. thaliana grown hydroponically. For each development stage studied, plants were fed with a drop (10 µl) of ¹⁴C sucrose on a mature leaf, after gentle scrubbing with carborundum. After 5 h of transport, the radioactivity was counted in the rosette (grey), stem (white), roots (black), and external medium (dots), and the distribution of radioactivity calculated among the three compartments. Each result is the mean ± SE of measures obtained from three to eight individual plants from two independent experiments