Figure 2.

(a) Comparison of the water content (water weight percentage) from caulinar leaves of Arabidopsis plants grown in two substrates with different water retention capacity: Metromix (higher retention, dashed line) and Turface (lower retention, continuous line). Irrigation was halted at t = 0. Leaf tissues from plants grown in Turface show faster water loss rate compared to plants grown in Metromix. Plants in Turface showed relatively slow dehydration over the first 8 to 10 h with a sudden rate change after approximately 15 hours of water supply halt, dehydration of the tissue became very rapid and tissues lost most of their water in the following 5 hours. Samples from Metromix showed a relatively steady tissue water content over the first 30 h and slower dehydration through the following 25 h, culminating with almost total water loss around 70 h after halting water supply. A continuously watered plant grown on Metromix substrate was also monitored as reference (dash-dotted line). (b) The osmotic potential of both substrates was also determined. This shows the difference in water retention capacity of these substrates.