Light energy can harm Photosystem I (PSI) in plant leaves, but we don't know much about how this happens. Previous studies focused on Photosystem II (PSII) photoinhibition, which is more severe. This study looked at how different light colors affect PSI photoinhibition in intact leaves. They found that blue and red light caused more PSI damage compared to white light. The rate of PSI photoinhibition was highest in blue and red light, followed by white and green light. This suggests that chlorophyll absorption is responsible for PSI damage in leaves. The study also showed that PSII and PSI can be damaged independently by different light colors.