Abstract
We have shown that the rosette leaves of Arabidopsis thaliana exhibit negative gravitropism and nastic movement in dark. These leaf movements do not occur under white light. To investigate interaction between light and movement of leaves, monochromatic light (450, 520, 630, 670 and 730 nm) was irradiated for 9 h in the large spectrograph (National Institute for Basic Biology) on the rosette leaves of Arabidopsis. Plant that irradiated red (630, 670 nm) or blue light (450 nm) differed from those under other light condition in terms of leaf movement. Detailed analysis revealed that the leaf movement is the sum of the shoot axis-dependent movement controlled by red light and gravity-dependent movement controlled by blue light. A complex system is used for the leaf positioning of Arabidopsis.
