Pests (insects, weeds, pathogens) are an important component for sustaining rice-wheat systems. Among them, soil- and seed-borne pathogens may play a specific role. Cropping practices may affect the dynamics of these pathogens, both in their survival and epidemic phases. More specifically, the carryover role of other crops in rotation with rice may be critical for these diseases. Pathogen interactions may also alter disease patterns in a field. These interactions remain largely unknown, and we report here some preliminary results on this topic.