After harvesting arable crops, residues are left in the field as dead plant material. Results observed in current PPS projects showed that the pathogens Alternaria solani (potato early blight) and Cercospora beticola (Cercospora leaf spot in sugar beet) can survive in crop residues of the host and in some other crops grown in rotation (including cover crops). These results were found in four years of sampling in a crop rotation system in sand, however it is necessary to have a more complete overview, not only in sand but also in clay, and to further gain knowledge of other key fungal pathogens in other arable crops.
