It's in the Genes: Research Pinpoints How Plants Know When to Flower

Ability to regulate flowering in plants at desired time of the year may contribute to increased food crop yield and possibly for use in biofuels. To this end, researchers at the University of Washington conducted research in Arabidopsis thaliana. Researchers led by Takoto Imaizumi reported in the journal Science the discovery of FKF1 protein which they said could be the key player by which plants recognize seasonal change and thus know when to flower.

Previous studies have revealed the presence of a flowering protein called Flowering Locus T produced in the leaves and travels to the shoot apex. The protein starts the molecular changes that lead to the development of flowers. The photoreceptor FKF1 protein on the other hand, is expressed in the late afternoon everyday, and if it occurs during long day, the light will activate the flowering mechanism involving Flowering Locus T. Hence, in short days, the protein is inactivated and flowering will not occur. This system keeps plants from flowering and reproduction during short days and long nights.

The original research article can be seen at  http://www.washington.edu/news/articles/its-in-the-genes-research-pinpoints-how-plants-know-when-to-flower.