The Esca Disease Complex

Esca is a grapevine wood disease that seriously affects vine yield and longevity. Our knowledge of this disease and its causes has changed profoundly in recent years, as it has become clear that esca in fact comprises a number of distinct diseases and that the main fungal agents (primarily vascular pathogens) invade the vines not only through wounds applied in the field but also as a result of nursery practices. When vines become infected in the nursery, the diseases that develop may vary, from Petri decline to full-blown esca, with or without white decay. With the banning of sodium arsenite no chemical control is now available and sanitary practices in the nursery are suggested as being the best approach to eliminate or at least reduce pre-planting infections from the tracheomycotic fungi. In the absence of chemical prevention, some preventive and curative action can also be taken in the field to reduce infections or to hamper symptom appearance in esca-infected vines, as will be described.