On the epidemiology of plum pox virus in the Czech Republic.
The distribution of natural sources of plum pox potyvirus (PPV) on stone fruits in the Czech Republic was investigated. Wild plums were heavily infected in central Bohemia and Moravia. Myrobalan (Prunus cerasifera subsp. myrobalana) was the second main natural source of PPV. The virus was also detected in some plants of blackthorn (P. spinosa), growing in PPV-affected areas, showing distinct symptoms on leaves, very similar to those on plums. PPV was not detected in blackthorn shrubs growing in forests and in areas where PPV is not or only occasionally present. P. spinosa is considered a secondary source of infection.