Light signaling and plant responses to blue and UV radiations—Perspectives for applications in horticulture

• Blue light and UV-radiations modulate both photomorphogenesis and photosynthesis.
• Several plant photoreceptors perceive UV and blue wavelengths.
• Plant develops protective responses to UV and high fluence blue radiations.
• UV and blue wavelengths interact on processes involved in plant quality.
• LEDs are tools to adapt light spectrum to plant needs.

Ultra-violet (UV) and blue radiations are perceived by plants through several photoreceptors. They regulate a large range of processes throughout plant life. Along with red radiations, they are involved in diverse photomorphogenic responses, e.g., seedling development, branching or flowering. In this paper, we present an overview of UV- and blue-radiations signaling pathways in some key physiological processes and describe effects of plant exposure to these wavelengths on phenotype as well as on contents in useful metabolites and resistance to bio aggressors. Taking these knowledge into account, we finally discuss possible applications of the use of such radiations to improve plant production in horticulture.