Control of flowering

Plant flowering is of great importance because it directly effects how effective plants are at reproducing. Many environmental and endogenous factors regulate when plants flower, one of the most pivotal being day length. Plants can generally be divided into those that flower in response to short (SD) or to long days (LD). In Arabidopsis thaliana (a LD model plant), the G1 gene product activates CO, which then activates a downstream floral activator (FT), resulting in flowering under LD conditions. In the April 17 Nature, Ryousuke Hayama and colleagues from The Nara Institute of Science and Technology, Japan, investigated the role of the orthologues of GI, CO, and FT — OsGI, Hd1, and Hd3a respectively — in rice, a SD plant. They found that the rice orthologues act differently to control flowering (Nature, 422: 719-722, April 17, 2003.).

Hayama et al. generated transgenic rice that overexpresses OsGI under both SD and ...