Figure 3.

Pre-irradiation does not enhance phototropic responsiveness to high intensity unilateral blue light. (A) Three-day-old etiolated WT seedlings were maintained in darkness (Control) or irradiated with 20 μmol m⁻² s⁻¹ of over-head red light for 15 min (Red) or (B) irradiated with 20 μmol m⁻² s⁻¹ of over-head blue light for 15 min (Blue) before being placed into 10 μmol m⁻² s⁻¹ of unilateral blue light for 3 h. Hypocotyl curvatures were measured every 10 min and each value is the mean ± S.E. of 20 seedlings.