Collect sample in appropriate times of the year:
- Fall through the dormant season is the best time for detecting many of the grapevine viruses
- Spring and early summer is the ideal time for sampling if nepoviruses (GFLV, ToRSV) are the culprits
- Fungal pathogens can be sampled and detected throughout the year
Sampling guidelines may vary depending on the purpose of testing
- For detection of bacterial and fungal diseases, take sample from symptomatic parts of the vine. Graft union, crown and roots should be included in the sample suspected for vine decline disease and Agrobacterium.
- For detection of viruses, ideal sample is taken from individual symptomatic plants (See Figure). Sampling from different sites of the same vine increases chances of detection since the pathogen propagules are not evenly distributed within a vine. Mature canewood is good material throughout the year. For spring-time nepovirus tests, young shoot tips can be collected.
- For virus screens in propagation material, follow the above sampling guidelines for virus testing.
- For virus testing on the rooted nursery vines, please cut off the root-portion on the vines, approximately 4 inches below the graft union or the top of the vines). Discard the roots. You may use up to 10 nursery vines per sample.
Sampling for Grapevine Viruses
- Sample should consist of 5 canewood pieces, each up to 6 inches long, and selected from the basal portion of canes in different locations of an individual vine. Composite samples are not recommended. Leaves and petioles can also be included in a sample.
- Place each sample into its own bag and label the bag accordingly. Proper labeling will help you to identify the vine and match it with the test results for that vine.
- Keep the samples cool. Ice packs (blue ice) wrapped with a newspaper in a cooler together with samples is recommended.
- Sign and include a sample submission form with your sample.
- Ship your samples for delivery within 1-2 days to:
AL&L Crop Solutions
7769 N. Meridian Rd.
Vacaville, CA 95688