Light as a stressor and its impact on biotic and abiotic stress
responses in plants
Abstract
Light is important for plant life as a source of energy to drive
photosynthesis but also as an environmental signal regulating
development or cellular events such as resetting of the circadian clock.
Light itself can cause stress such as excess light, fluctuating light,
photoperiod and ultraviolet light stress. Light quality, quantity and
light duration are important sources of information to prepare plants
for future light stress events. Recurring light stress results in
acclimation processes to the changing light environment. Furthermore,
light regulates the responses of plants to diverse biotic and abiotic
stresses. For example, short day conditions or shady environments prime
thermotolerance and increase cold acclimation. Similarly, during drought
stress, light signaling is important for the plant´s stress response.
Additionally, the light environment affects the plant´s responses to
biotic intruders such as pathogens or insect herbivores. Light influence
many stress responses resulting in positive growth-defense trade-offs.
Under shade, however, plants prioritize growth over defense and stress
responses. In this review, we summarize the impact of light as a
stressor and its influences on abiotic and biotic stress responses with
special focus on the role of the different light receptors and the
crosstalk between light signaling components and stress response
pathways.