P. savastanoi strains used in this study with the designation of their geographical origin, the variants for each SNP marker examined and their SNP-group.

aCFBP, Collection Française de Bactéries Phytopathogènes, INRA, Angers, France; ITM, Culture collection of Istituto Tossine e Micotossine da Parassiti vegetali, C.N.R., Bari, Italy (from A. Sisto); LPVM, Culture Collection of Laboratorio di Patologia Vegetale Molecolare, Dipartimento di Biotecnologie Agrarie, Università degli Studi di Firenze; NCPPB, National Collection of Plant Pathogenic Bacteria, York, UK (http://www.nctc.org.uk); PD, Culture collection of Plant Protection Service, Wageningen, The Netherlands; PVBa, Culture Collection of Dipartimento di Patologia Vegetale, Università degli Studi di Bari, Italy (from A. Sisto); ES, MC and AG, from E. Santilli, M. Cerboneschi and A. Gori, respectively.bCode used at LPVM for strains ITM317, NCPPB1006 and ES23 are Psv5, Psf134 and Psn23, respectively.cSG = SNP-group.