Planting Clean Grapevine Stock Disease Testing by Judit Monis

Issue Date: April / May 2009

Every year a vineyard manager or grower needs to make planting, top working, or vine removal decisions. These are the key activities for ensuring a healthy vineyard with a good yield potential.  An integral part of this process involves the assessment of the level of infection, if any, present in current vines as well as available scions and rootstock. Eurofins STA laboratories Plant Health Services Division (eSTA PHS) specializes in testing grapevines for disease causing agents (i.e., pathogens). eSTA PHS has developed reliable procedures for the detection of the different pathogens that cause disease in grapevine.   The results from such testing provide the information needed for sound decision making.  

The biggest challenge is the collection and submission of samples in order to detect pathogens accurately. Collecting samples at the right time of the year and at the appropriate vine location is not always convenient. Developing a testing plan that fits with the long term vineyard planting plan is necessary. However, in all cases the best return on investment follows if simple procedures are followed.  

The time to submit samples of planting material for testing should coincide with the time the grower decides which rootstock-scion combination will be ordered at the nursery.  In most cases, nurseries are able to trace their mother vines and organize cuttings in specific bins.  A representative sample should be collected from each bin of rootstock and scion material that will be used for grafting.  The correct sample will depend on the diagnostic tests ordered.  For sensitive and accurate detection sampling must be done in the correct season.  As noted in the table below, samples will need to be submitted at different times of the year to cover the whole spectrum of grapevine disease causing agents (unless it is possible to remove a whole vine).

In a simple world, this would be all the testing needed.  Because of the potential of virus spread and fungal infections in vineyards it is important to test samples after field finishing or cold storage.  Visual inspections are important but most likely cannot identify the causal agent.  Collecting samples with and without symptoms will help the vineyard manager determine if the visual symptoms are due to the presence of a disease agent or other stress factors.

Start developing your disease testing strategy today.  This spring submit samples for HealthCheck Panel B.  HealthCheckTM Panel B includes the decline and degeneration disease causing viruses: Arabis mosaic virus (ArMV), Grapevine fanleaf virus GFLV, Tobacco ringspot virus (TRSV), and Tomato ringspot virus (ToRSV).  These viruses are transmitted by nematodes. Work in our lab has shown that although dormant wood from heavily infected vines may be used, young tips and leaves collected in the spring better enables the detection of the viruses included in HealthCheck Panel B. Please check our website, www.stalabs.com, for updates and call us to discuss your specific testing needs..