CHARACTERIZATION OF THE SWEET CHERRY ISOLATE OF PLUM POX POTYVIRUS

An isolate of plum pox potyvirus from sweet cherry (PPV-SwC) in southe rn Italy was investigated. The isolate was mechanically or graft trans missible to different Prunus and Nicotiana spp. but not to Chenopodium spp. It was transmitted also by Aphis fabae and Myzus persicae in a n onpersistent manner. Restriction fragment length polymorphism analysis indicated and nucleotide sequencing confirmed that the isolate lacks AluI and RsaI sites in the C-terminal region of the coat protein (CP) gene. Western immunoblot results showed that the PPV-SwC CP has an ele ctrophoretic mobility similar to that of strain PPV-D and faster than that of strain PPV-M. Double-antibody sandwich indirect enzyme-linked immunosorbent assay of the CP showed that PPV-SwC, although reacting w ith universal monoclonal antibodies to PPV, failed to react with antib odies specific to strains M and D. Results indicate that PPV-SwC is di fferent from conventional strains of PPV but closely related to the so ur cherry isolate of PPV from Moldova.