ABSTRACT
Bamboos are the gigantic member of grasses and phylogenetically closer to the monocot reference plant O. sativa. However, it portrays wide range of variation with respect to flowering time (1–120 years), flowering extent (sporadic or gregarious). Besides the unusual delay in flowering, another important character is mass death of all the flowering culms, which is known as monocarpy or semelparity. Therefore, bamboo flowering has a huge effect on forest ecology and economy.
Induction of flowering is one of the most crucial steps in plants life. Signals from various external (light, temperature) and internal (phytohormones, physiological age) cues need to be synchronized to decide the timing of flowering. In photoperiod pathway the duration (photoperiod) and spectrum (red or blue) of light regulate flowering time. The photoreceptors receive light stimuli and then the circadian clock genes synchronise the light signal and transfer it to the circadian clock integrator gene CONSTANS (CO). CO ultimately induces the pathway integrator gene FLOWERING LOCUS T (FT) and thereby ensure flowering.
The genetic studies on flowering have predominantly been done on the annual, model dicotyledonous Arabidopsis thaliana and monocotyledonous plants which fails to unravel the molecular mechanism of flowering in non-model perennials such as bamboo. Therefore, the major focus of this article is to review the current state of knowledge on photepriodic genes in bamboo and their involvement in bamboo flowering.
