Figure 8.

Appearance of a red perilla leaf at the 5th node counted from the bottom of the main stem 2 weeks after treatment initiation (Experiment 3). Perilla plants were irradiated for 1 or 2 h every 1 or 2 h for 6 h, from 18:00 to 6:00. The UV-B radiation intensity at the canopy level was set to 0.05 or 0.1 W m⁻². Leaves at the 5th node counted from the bottom of the main stem were harvested 2 weeks after treatment initiation. Leaf blade length under treatment conditions of the control, and under conditions of exposure to 0.05 W m⁻² for 1 h, 0.1 W m⁻² for 1 h, 0.05 W m⁻² for 2 h, and 0.1 W m⁻² for 2 h was 11.3 ± 0.6, 10.2 ± 1.5, 8.4 ± 1.2, 10.5 ± 0.5, and 8.0 ± 0.7 cm, respectively (mean ± SE, n = 5). Each black bar indicates 5 cm.