Disease and loss in plants. Symptoms. Parasitism and pathogenicity. Characteristics of viruses, phytoplasmas, bacteria and fungi. Diagnosis by traditional methods and biochemical markers. Disease cycle. Relationships host – parasite. Epidemiology. General topics on disease control. Cultural methods, pathogen-free propagating materials. Use of resistant varieties. Quarantine and plant passport. Physical, chemical and biological methods. Basic concepts of integrated and biological control. Grapevine diseases: fanleaf, leaf roll, rugose wood complex, bois noir, flavescence dorée, downy mildew, powdery mildew, grey mould and sour rot, escoriose, trunk diseases.