Key Points Excess light can damage Photosystem II in plants, with slower repair rates observed in colder conditions. Plants acclimated to cold for three days showed enhanced photoinhibition repair rates. Ecotypes from colder regions demonstrated greater increases in repair capacity. Arabidopsis thaliana was studied under controlled temperatures of 22°C, 12°C, and 5°C. Plants require light to grow, but excessive light can damage their photosynthetic system, specifically Photosystem II. While plants growing in full sunlight have mechanisms to repair this damage,...