Figure A1.

Dye-loaded leaf apoplast of Vica faba L. To prepare a leaf for measurement, dye is partially loaded into the leaf apoplast. The loading procedure can be monitored by the darker appearance of the leaf apoplast. This dark shade disappears after the water has left the leaf through the stomata (compare with Figure 2). Images were taken immediately after the dye was loaded (A), 2 min after loading (B) and (C) 15 min after loading. This time series demonstrates that the water exits the leaf through the stomata after at least 15 min.