First Report of Plum pox virus Strain M Isolates in Apricot in Sicily, Italy

Sharka or plum pox disease is one of the most economically important virus diseases of stone fruits. Plum pox virus (PPV), the causal agent, is a member of the genus Potyvirus of the family Potyviridae transmitted by aphids in a non-persistent manner and by grafting. To date, nine PPV strains have been described on the basis of their biological, serological, and molecular properties: M and D are the most widespread and economically important strains, PPV-Rec and PPV-C have been reported mainly in Europe, PPV-EA confined to Egypt, PPV-T to Turkey, PPV-W from Canada, Ukraine, Latvia, and Russia, PPV-CR detected in Russia, and finally a putative PPV strain infecting plum in Albania described as the ancestor of the M. PPV-M is responsible for major epidemics in many Italian regions and despite phytosanitary measures, the infection rate increases each year. The D and Rec isolates are sporadically reported while PPV-C, once signaled in Apulia, has been successfully eradicated. Except for a report from the 1980s...