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High resolution digital imaging was used to identify sites of photo‐oxidative stress responses in Arabidopsis leaves non‐invasively, and to demonstrate the potential of using a suite of imaging techniques for the study of oxidative metabolism in planta . Tissue‐specific photoinhibition of photosynthesis in individual chloroplasts in leaves was imaged by chlorophyll fluorescence microscopy. Singlet oxygen production was assessed by imaging the quenching of the fluorescence of dansyl‐2,2,5,5‐tetramethyl‐2,5‐dihydro‐1 H ‐pyrrole (DanePy) that results from its reaction with singlet oxygen. Superoxide and hydrogen peroxide accumulation were visualized by the reduction of nitroblue tetrazolium (NBT) to formazan deposits and by polymerization with 3,3′‐diaminobenzidine (DAB), respectively. Stress‐induced expression of a gene involved with antioxidant …