1. Department of Sustainable Crop Production Università Cattolica del Sacro Cuore 29122 Piacenza Italy
2. CREA‐DC, Consiglio per la Ricerca in Agricoltura e l'Analisi dell'Economia Agraria, Research Center for Plant Protection and Certification 00156 Rome Italy
3. Department of Environmental Biology University of Rome “Sapienza” 00165 Rome Italy
4. Department of Organic and Industrial Chemistry University of Parma 43124 Parma Italy
5. BK21 plus program, College of Biological Sciences and Biotechnology Chungnam National University Daejeon 34134 South Korea
6. Department of Plant Pathology and Microbiology Texas A&M University, College Station TX 77843‐2132 USA