Total RNA extraction and RT-PCR was performed with coat protein (CP) specific primers for PNRSV (F:5'-TCACTCTAGATCTCAAGCAG-3'), (R:5'-GAGCTCTGGTCCCACTCAGG-3') as described by Spiegel et al. ([3]) that amplified a fragment of 616 bp. 3 Spiegel S, Tam Y, Maslenin L, Kolber M, Nemeth M, Rosner A. Typing Prunus necrotic ringspot virus isolates by serology and restriction endonuclease analysis of PCR products.