Abstract
The effect of visible light of low energy on the lamina inclination was investigated in order to make clear photomorphogenesis in rice seedlings. By an irradiation of 5 min/day for 7 days, an inhibitive effect on the lamina inclination of 2nd leaves in etiolated seedlings was distinctively observed at all the wave length of visible light used (fig. 3). By the irradiation for 4 days, a decrease of the inhibitive effect on the inclination was detected by green light (fig. 4). The lamina inclination in etiolated rice seedlings was the most sensitive at age in 4 and 5 days after seeding (fig. 5). At this sensitive stage, the irradiation with 2 times of 10 min by red light (650 nm) did not make to induce any inclination of leaves, but a slight inclination was induced by blue (400 nm) and green (500 nm) light. The inhibitive effect on lamina inclination appeared even by 1 min of blue, green and red light (fig. 6). From this result, it was confirmed that such low energy as 42μW/cm2 of red light is able to affect the lamina inclination. By the irradiation of visible lights used the elongation of internode was inhibited. But the sheath elongation of 2nd leaf was contrarily stimulated, and the lamina length of 2nd leaf was not almost affected by all the lights used.
