1. Department of Genetics and Microbiology, University of Pavia, 27100 Pavia, Italy (R.S., C.M., R.C.); Department of Environmental Agronomy and Crop Production, University of Padova, Agripolis, 35020 Legnaro, Italy (S.V., S.C.); Institute of Plant Biotechnology, University of Paris-XI, 91400 Orsay, France (C.B.); and Department of Botany and Plant Ecology, University of Sassari, 07100 Sassari, Ital