A recombinant strain of Plum pox virus in peach in Bulgaria.

摘要

Of 88 leaf samples collected from three peach orchards in south-west Bulgaria and tested for Plum pox virus (PPV) by TAS-ELISA, 32 (36.4%) were positive for PPV-M. When these samples were tested by IC-RT-PCR targeting the (Cter)NIb-(Nter)CP genomic region using PPV-M and PPV-Rec strain-specific primers the presence of the M strain was confirmed in 16 of them (50%), whereas the Rec strain was detected in 15 samples (47%). Mixed infection of both strains was found in a single sample. The nucleotide sequences of the (Cter)NIb-(Nter)CP genomic fragment of 13 PPV isolates showed a 98-100% identity with PPV-Rec isolates and 97-98% identity with the reference isolates. The maximum nucleotide identity of PPV-Rec isolates with PPV-M and PPV-D isolates was 92-93% and 84-85%, respectively. These results show that PPV-Rec is widely distributed in peach orchards in southwestern Bulgaria.