In perennial crops virus diseases are usually caused by mixed infections rather than by individual viruses. Understanding the contribution of each virus in disease development, the interactions between viruses and how each virus spreads in the field allows for development of control measures that are targeted for disease control rather than controlling all viruses in a complex. There are multiple types of virus-vector interactions and this information can be used to inform vector control strategies to manage virus diseases. Information on virus-vector interactions and insect biology for controlling a disease caused by a virus complex in raspberry will be presented. Understanding the biology of multiple vectors as well as multiple types of virus-vector interactions for a vector of multiple viruses will be presented as a model for managing virus disease in strawberry in different environments. The goal is to describe a systems approach for controlling virus diseases in vegetatively propagated crops from developing clean plants through to fruit production.

• Robert R. Martin(USDA, Agricultural Research Service, Horticultural Crops Research Unit)