Photosynthesis forms the basis for primary production and fuels the
formation of biomass with valuable chemical composition in plants.
Although photosynthesis requires sunlight, the very nature of sunlight
also has negative effects on photosynthesis. Visible light and
ultraviolet light, the inherent parts of sunlight, may cause damage to
the photosynthetic machinery and other cellular components. Plants have
therefore evolved various protective and response mechanisms, which
monitor the intensity, wavelength, duration and direction of light and
mitigate the negative effects of light stress. Currently, the underlying
molecular mechanisms and functional overlaps among light receptor and
chloroplast signalling, and the consequent light-dependent adjustments
in plant performance are emerging. The ability to delicately sense,
signal and respond to the ambient light environment forms a key
contributor to plant growth and productivity.