FIRST REPORT OF GRAPEVINE VIRUS D (GVD) IN AUTOCHTHONOUS GRAPEVINE VARIETIES IN TURKEY

Abstract

Rugose wood is a complex of graft-transmissible disorders of the grapevine (Vitis spp.). At least six different viruses belonging to the genera Vitivirus and Foveavirus in the family Betaflexiviridae are associated with the disease which is distributed worldwide (Martelli, 2015). Among these viruses, grapevine virus A, grapevine virus B and grapevine rupestris stem pitting-associated virus were reported in Turkish vineyards (Martelli, 2014; Buzkan et al., 2015), whereas no information is available on the occurrence of grapevine virus D (GVD). Therefore, the presence of GVD was investigated in autochthonous grapevine cultivars from two viticultural areas in Turkey, i.e. Eastern Mediterranean and Southeast Anatolia. Total RNA was extracted from 142 samples and tested for the presence of GVD by RT-PCR using primers CP7V/CP471C (Abou-Ghanem et al., 1997). A 474 bp product corresponding to a fragment of the coat protein gene was amplified from 13 samples, accounting for a prevalence of 9%. The nucleotide sequence obtained from PCR amplicons was subjected to BLASTN analysis to confirm the identity of the target virus. The Turkish isolates showed 90% nucleotide sequence identity with a GVD isolate from Italy passaged onto a herbaceous host (Nicotiana occidentalis) (GenBank accession No. Y07764) and 98% with a GVD isolate from Brazil (JQ031716). GVD was only detected in grapevines from Southeast Anatolia, where it is a very common practice to establish vineyards with propagation material exchanged among growers without any pathogen testing. To our knowledge, this is the first report on the occurrence of GVD in Turkish grapevines.