Preliminary data on the presence of grapevine pinot gris virus in Lombardy

Grapevine Pinot Gris virus (GPGV) was identified for the first time in 2012 in Trentino region (northern Italy). Subsequently, GPGV was reported in other Italian regions and in other countries. This Thricovirus, family Betaflexiviridae, was associated with grapevines showing leaves deformation, chloric mottling and puckering. During a survey carried out in six Chardonnay and Pinot noir vineyards in Lombardy, vines showing GPGV-like symptoms were observed. Total RNAs were extracted from leaves and PCR reaction was performed on cDNA, obtained using random primers and RevertAid M-MuLV Reverse Transcriptase, with primer pairs amplifying three distinct GPGV genomic regions (replicase, movement and coat proteins). PCR products related to movement and coat protein genes were sequenced on both strands, assembled, and compared with GenBank. GPGV was detected in 14 out of the 29 sampled grapevines; only 3 of these were symptomatic. Utilized primers pairs showed diverse sensitiveness: GPGV was detected in 12 plants using primer pairs for movement and coat protein genes, and in six grapevines using primer pair for replicase. Nucleotide sequences relative to movement (partial) and coat protein genes of Lombardy GPGV isolates share 96.5 to 98% identity with GPGV isolates from Italy, Slovak and Czech. The finding of this virus in a new area (Lombardy) leads to the consideration that GPGV is widely present in Northern Italy and that further investigation should be done in order to assess its role in the disease aetiology.