Résumé
Six Prunus genotypes used as rootstocks, and including two interspecific hybrids, were chip-inoculated with the sour cherry isolate of Plum pox virus (PPV-SoC). The ability of the virus to infect different Prunus species was studied. The symptoms were noted and their location within the tree structure was determined by AMAPmod methodology. After a 3-year experimental period, 5 of the 6 Prunus genotypes tested (‘GF8.1’, ‘Jaspi’, ‘F12.1’, ‘Edabriz’ and ‘SL64’) were infected in vivo and showed different patterns of contamination. Generally, symptomatic leaves in all the infected genotypes were not consecutive on the shoots, thus resulting in a large symptomatic zone. The virus was characterised by irregular distribution in all the infected Prunus plants. The Colt genotype could not be infected in vivo, but PPV-SoC could be transmitted by in vitro grafting. We conclude that PPV-SoC may systematically infect different cherry and plum rootstocks. Therefore, the host range of PPV-SoC appears to be wider than that of conventional PPV isolates