Many hands make light work.

The responses of plants to the light environment have fascinated biologists for well over 100 years (Briggs, 2006). Early studies in photomorphogenesis focused necessarily on morphological aspects of plant responses; germination, seedling establishment, plant architecture, and flowering time are all regulated by light. More recently, and particularly with the advent of the genetic model Arabidopsis thaliana, the focus has shifted to understanding plant responses at the molecular level. Understanding and genetically manipulating these processes may provide the subtle control of plant growth that will permit successful alteration of these traits for agricultural benefit. This Focus Section, based on the Photomorphogenesis session at this year's Society for Experimental Biology annual conference, contains reviews directed at both the progress in understanding the molecular basis of light-signalling pathways and how to translate this information for agricultural gain.

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