With many vineyards currently being prepared for replanting and grafting, it is important to maximise the long-term health of the vineyard by using pest-free propagation material. Propagation material which carries viruses and other pathogens can have devastating effects on vine growth, yield and fruit quality. It is recommended that propagation materials are purchased from nurseries that have adopted the Vine Industry Nursery Accreditation Scheme.
When grafting from one variety to another, the virus status of the rootstock should be known, even if the vines are symptomless. This is because varieties vary in virus sensitivity, and the scion may perform badly if a virus is present.
Management practices can help contain the spread of viruses and reduce losses, so established vineyards should be routinely inspected for the presence of virus-associated symptoms. If virus infection is suspected, diagnostic testing should be undertaken on vines with symptoms. The removal of infected vines and control of insect vectors such as mealybug and scale may reduce the spread of the viral pathogen. If the virus status of new plantings is not known, virus testing is recommended because even if the vines are symptomless, they may act as a reservoir for viruses that could affect other sensitive varieties.
Virus diagnosis is typically undertaken on dormant cuttings, so now is the right time to collect and submit samples for analysis. This service is offered by AWRI Commercial Services in South Australia or Crop Health Services in Victoria. AWRI Commercial Services has recently updated its resources on virus testing including updated sample submission information and a new fact sheet with details about sampling and analysis. More general information about the services available can be found at the virus testing homepage.
For information about AWRI Commercial Services’ virus testing services, please contact Dr Nuredin Habili on nuredin.habili@awri.com.au or 08 8313 7426.
For other technical queries, please contact the AWRI helpdesk on helpdesk@awri.com.au or 08 8 313 6600.