Carbon allocation is critical for crop yield. Our group studies nutrient transport processes in plants, both regarding yield potential and yield when infected by pathogens. We use a wide range of tools to identify the key transporters, for example for carbohydrates in order to study everything from structure to function and regulation. A main tool set includes fluorescent biosensors for a wide range of small molecules, from sugars to hormones. We develop tools for monitoring the activity of proteins in vivo (in particular fluorescent transport activity sensors). We surgically engineer permissive sites in transporters that act as susceptibility factors to create robust broad-spectrum pathogen resistance in crop plants.