Grapevine Pinot gris virus (GPGV) was described in Italy using a metagenomic approach: next-generation sequencing of the virus-derived small RNAs. Since that time, it has been reported all over the world. The presence of GPGV is associated with grapevine disease, but most of the time, the disease is asymptomatic. Although the host range of this virus has not been investigated, it has been found in the non-Vitis hosts, Silene latifolia and Chenopodium album. We investigated the presence of GPGV in grapevine and other plant species growing as weeds in the vineyard. Using RT-PCR, we identified GPGV in seven non-Vitis hosts: Ailanthus, Asclepias, Crataegus, Fraxinus, Rosa, Rubus, and Sambucus. In the case of Rosa and Rubus, this finding was supported by Northern blot detection of the virus. GPGV strains in non-Vitis hosts belong to the asymptomatic clade, and are clustered according to their original geographic locations. The presence of GPGV in species other than grapevine shows that besides well-known vector and propagating material-based infections, other possible entry sites for the virus can exist, which have to be taken into consideration when developing reliable regulation strategies.
Keywords: GPGV; alternative host; asymptomatic variant; grapevine; non-Vitis; plant virus; survey.