R. Abou Kubaa, M. Digiaro, G. Bottalico, T. Elbeaino
doi: 10.4454/jpp.v1i1.3200
Apricot vein clearing-associated virus (AVCaV), the representative of a putative new genus in the family Betaflexiviridae, was recently discovered in southern Italy in an apricot tree showing vein clearing of the leaves (Elbeaino et al., 2014). To assess its natural host range and distribution, RT-PCR assay was carried out using two specific sets of primers designed on the polymerase (Rps/Rpa: 5’-TTGATGCCTCACAAGACCAAT-3’, 5’- CGTTACTCTGTTCCGCAAAAAG-3’) and coat protein (CPs/CPa: 5’- CTTTTCCGGGATATCTGCACA-3’, 5’-ACAGTACCTCTCGCCTCGAAA-3’) genes of the viral genome, which amplified fragments of 629 bp and 607 bp, respectively. Tested samples consisted of leaf tissues (petioles and midveins) collected from a large number of cultivars of stone fruit species grown in a collection of the Faculty of Agriculture of the University of Bari (Italy), i.e. almond (39 cultivars), peach (47), cherry (34), plum (30), apricot (40) and 20 different rootstocks. Products of the expected size were amplified from three plums of cvs Angeleno, Autumn Giant and Stanley and one apricot of cv. Jameloppis in which AVCaV was originally detected (Elbeaino et al., 2014). All the other tested plum, apricot, cherry, peach and almond trees were PCR-negative, as well as the rootstocks. Sequences of the products amplified from the RdRp and CP genes were 99-100% identical to those of the AVCaV isolate from apricot deposited in Genbank (HG008921.2). No symptoms were observed on naturally infected trees nor on graft-inoculated woody indicators (GF 305, P. armeniaca cvs. Priana and Tilton, P. persica cv. Elberta, P. cerasifera), indicating that AVCaV infections to stone fruit species are largely latent.