DAF-fluorescence without NO: Elicitor treated tobacco cells produce fluorescing DAF-derivatives not related to DAF-2 triazol

► DAFs are widely used for bioimaging of nitric oxide. ► We show that DAF-2 or DAF-FM fluorescence may rise completely independent of NO. ► Elicited tobacco cells secrete H2O2 and peroxidase. ► Both react with DAFs forming hitherto unknown fluorescing DAF-derivatives different from DAF-2 triazol.