Distribution of olive tree viruses in Italy as revealed by one-step RT-PCR

We have used a one-step RT-PCR protocol to detect and identify each of the eight viruses most commonly found in olive trees namely: Arabis mosaic virus (Ar-MV), Cherry leaf roll virus (CLRV), Cucumber mosaic virus (CMV), Olive leaf yellowing associated virus (OLYaV), Olive latent ring spot virus (OLRSV), Olive latent virus-1 (OLV-1), Olive latent virus-2 (OLV-2), and Strawberry latent ring spot virus (SLRSV). We have assayed 345 samples collected from olive fields in Italian areas in which national and local olive tree cultivars and selections are grown. The average percentage virus infection of olive trees was 32.8%. Among the eight virus-es assayed, only OLYaV (20.9%), SLRSV (7.8%) and CLRV (4.9%) were detected. The most common virus was OLYaV, which was found at a high percentage in southern Italy. SLRSV was the main virus in central Italy whereas CLRV was detected in five samples from Latium, Umbria and Sicily and in all analyzed trees from Abruzzo.