Updated PubMed. Weather extremes are increasing worldwide frequently exposing plants to transient flooding. When floodwaters recede, plants have to cope with increased light intensity and elevated oxygen that favor excessive formation of reactive oxygen species (ROS). We report a novel molecular mechanism that helps Arabidopsis leaves cope with reoxygenation in the light that reveals a central role of the alternative electron tranport in mitochodria in cellular ROS management that is beneficial for photosynthetic recovery and provides tolerance to reoxygenation stress.