Grapevine Pinot Gris Virus (GPGV) was recently detected in Australia and has been reported in many international wine regions in Europe, the US, Canada and China. As well as Pinot Gris, it can infect a number of other wine and table grape varieties, including Pinot Noir, Traminer, Chardonnay, Merlot, Cabernet Franc, Cabernet Sauvignon and Shiraz.
GPGV is a member of the genus Trichovirus in the family Betaflexiviridae and multiple, genetically distinct isolates have been detected in diseased and symptomless grapevines.
The effect of GPGV on vine health is difficult to determine, as the virus is often found in infections with a mix of other viruses. However, it has been associated with economic losses, particularly in the presence of other viruses.
Symptoms associated with GPVG infection include:
- delayed budburst
- leaf distortion and mottling
- shortened shoot internodes
- increased berry acidity
- poor yield (reports of up to 80% yield loss).
The symptoms of GPGV may be confused with early season bud mite damage, cold injury or herbicide damage and are more frequently reported in Pinot Gris, Pinot Noir, Pinot Blanc and Traminer than other winegrape varieties.
Internationally, GPGV-associated symptoms have been reported in both young and old vineyards (2-50 years), with no relationship between incidence and vine age. Symptoms appear most distinct at the start of the season. They are less apparent on late season growth, with infected plants reported to ‘recover’ after veraison by producing symptomless shoots and leaves.
GPGV can be spread through the movement and exchange of infected propagation material such as potted vines, cuttings, rootlings and bud wood. The virus is also possibly transmitted by grapeleaf bud and blister mites (Colomerus vitis). There is no evidence to support the transmission of the virus mechanically on pruning or harvesting equipment.
For further information regarding GPGV reporting and diagnostics: