Drought stress affects how well tomato plants can make food through photosynthesis. Researchers studied how drought stress changes chlorophyll fluorescence in tomato seedlings. They used a chemical to mimic drought conditions and measured different parameters of chlorophyll fluorescence. The results showed that after drought treatment, the amount of chlorophyll in tomato seedlings decreased. The ability of the plants to transfer electrons also decreased under drought stress. Overall, the study provides important information for improving tomato cultivation and breeding practices.