Figure 3.

Effect of intermittent irradiation with FR light pulses for 1 d on further growth of the hypocotyl in darkness. A, Light regime. Two-day-old etiolated seedlings were treated as follows: one group (□) was kept under intermittent irradiation with FR light pulses (100 μmol m⁻² s⁻¹ for 10 s each) in 3-min cycles throughout the experiment, the second group (▴) was exposed to the same intermittent FR light irradiation for 1 d, then grown in the dark, the third group (●) was kept in the dark, and the fourth group (○) was kept under continuous irradiation with FR light (5.6 μmol m⁻² s⁻¹) for 9 d. White lines in black bars, FR light pulses with LEDs; black bars, darkness; white bars, continuous irradiation with FR light. B, Time courses of the hypocotyl growth in the wild type (top graph) and the phyB mutant (bottom graph). Error bars represent se.