Radiation hormesis in plants

In plants, radiation hormesis phenomenon occurs as enhanced growth, accelerated development, increased tolerance to stressors, or accumulation of compounds of interest in response to low-dose irradiation. This review summarizes the recent findings regarding radiation hormesis in plants in response to ionising or UV-radiation. While molecular mechanisms of UV-hormesis are clearer and involve sensing of UV-radiation by the specific photoreceptors, the precise molecular events underlying hormetic responses to ionising radiation are yet to be uncovered. Based on the available information, the scheme of possible pathways triggering radiation stimulation response in cells is discussed. It is argued that beneficial responses to low-dose ionising radiation may depend on the optimization of hydrogen peroxide (H2O2) levels and the interplay between the signalling pathways of reactive oxygen species (ROS) and phytohormones.