Characterization of plum pox virus isolates from Slovakia.

Plum pox virus (PPV) isolates from stone-fruit trees (plums, myrobalans, apricots and peaches) from orchards and gardens were characterized. To characterize their biological properties, several PPV isolates were transmitted by chip budding to GF 305 seedlings and mechanically to selected herbaceous test plants. The isolates differed in severity of infection, host range and symptomatology. A subgroup differentiation of 43 isolates from 22 localities of western and middle Slovakia was accomplished using reverse transcription-polymerase chain reaction (RT-PCR), immunocapture RT-PCR (IC-RT-PCR) and restriction analysis. These assays confirmed the presence of isolates belonging to PPV-M and PPV-D subgroups. PPV-M and PPV-D isolates were almost equally represented in tested samples. Tests of subgroup variability of PPV isolates from infected tolerant plum cultivars showed great predominance of PPV-M isolates.