Photoperiodic control of growth and reproduction in non-flowering plants.

Photoperiodic responses shape the plant fitness to the changing environment and are important regulators of growth, development and productivity. Photoperiod sensing is one of the most important cues to track seasonal variations. It is also a major cue for reproductive success. The photoperiodic information conveyed through the combined action of photoreceptors and circadian clock orchestrates an output response in plants. Multiple responses such as hypocotyl elongation, induction of dormancy and flowering are photoperiodically-regulated in seed plants such as angiosperms. Flowering plants such as Arabidopsis or rice have served as important model systems to understand the molecular players involved in photoperiodic-signaling. However, photoperiodic responses in non-angiosperm plants have not been investigated and documented in detail. Genomic and transcriptomic studies have provided evidences on the conserved and distinct molecular mechanisms across plant kingdom. In this review, we have attempted to compile and compare the photoperiodic responses in the plant kingdom with a special focus on the non-angiosperms.