Fig. 3.

Photographs of detached A. thaliana leaves with one half covered with black paper, and another half irradiated with UV-B (8 W·m⁻²) for 5 min and left in darkness (a and b) or under constant illumination (100 μmol·m⁻² ·s⁻¹ of white light, c) for the indicated time. The leaves were taken from plants dark-adapted overnight (a), or from plants kept in a growth chamber for 2 h after the dawn (b and c)