Johannes Kromdijk gave an open seminar during a CAPITALISE visit to Matteo Dell’Acqua’s Crop Genetics Group. His presentation described how important C4 crops such as maize and sorghum cope with light as both a resource and a stress factor. Light is important to drive photosynthesis and carbon assimilation, but plants routinely receive several times more light than can be processed via photochemistry. Dr Kromdijk explored how these crops deal with light fluctuations from strongly limiting to greatly exceeding the capacity for photochemistry. This seminar was held within the framework of the PhD programme in Agrobiodiversity at Scuola Superiore Sant’Anna and was supported by the CAPITALISE project.