VIRUS AND VIROIDS IDENTIFICATION IN TRADITIONAL APRICOT ORCHARDS SHOWING

“Viruela” disease produces important malformations in apricot fruits that become non-commercial. In this study, 35 traditional apricot orchards cultivated with the old Spanish cultivar ‘Búlida’ affected by “viruela” were analyzed in four different areas of the southeast of Spain, for two years. Leaf and fruit samples from four trees in each orchard with and without “viruela” symptoms were collected and analyzed by single RT-PCR against Apple chlorotic leaf spot virus (ACLSV). In addition, the multiplex RT-PCR test for the detection of other virus including, American plum latent pit virus (APLPV), Apple mosaic virus (ApMV), Apricot latent virus (ApLV), Plum bark necrosis and stem pitting-associated virus (PBNSPaV), Plum pox virus (PPV), Prune dwarf virus (PDV), and Prunus necrotic ringspot virus (PNRSV), was used. Finally, molecular hybridization and RT-PCR tests were assayed for the detection of Hop Stunt Viroid (HSVd) and Peach latent mosaic viroid (PLMVd). All the fruits showing “viruela” symptoms were ACLSV positive by RT-PCR. In addition, other viruses as PNRSV, PBNSPaV, ApLV, PDV and ApMV, were detected. HSVd was also detected in the 98% of the fruits assayed. These results suggest that ACLSV is related to the “viruela” disease. However, since HSVd was also detected in these samples, we cannot confirm that ACLSV is the only factor responsible for this disease. These results also indicate the high rate of virus infection in the traditional ‘Búlida’ orchards and suppose the first report of ApLV and PBNSPaV in apricot in Spain.