Abstract
The photoperiodic sensitivity 5 (se5) mutant of rice, a short-day plant, exhibits a drastic early-flowering phenotype and is photoperiod-insensitive due to phytochrome deficiency. We examined photomorphogenesis and flowering-time in se5 under monochromatic red (R) and blue (B) light conditions.
Leaf lengths in se5 were longer under R, but shorter under B than wild-type. The effect of mixed lights between R and B was also examined. Although the time of flowering in se5 under R+B was as early as in white-lights, se5 and the wild-type plants flowered late under R. This suggests blue-light signal can promote flowering in rice independently of red-light signaling mediated by phytochromes. In addition, the plastochron length in se5 was similar to that in the wild-type under R+B, but longer under R than wild-type. We discuss about red- and blue-light responses of leaf development and flowering in rice, compared with those in Arabidopsis, a long-day plant.
