Guest FORUM: Washington Blueberry Virus Surveillance (testing) program 2024

This spring, the Washington Blueberry Commission is sponsoring free testing for Blueberry Shock Virus (BlShV) and Blueberry Scorch Virus (BlScV). BlShV is widespread in Western Washington, and BlScV has recently been detected in about a third of the Whatcom and Skagit fields tested. BlScV weakens and kills plants. It is aphid-vectored, so a positive test for this virus means you need to manage aphids aggressively to avoid spread of the virus. Testing will be conducted by Phyto Diagnostics, which already runs thousands of assays for BC growers. Their testing has proven to be accurate, validated and affordable.  

Each farm paying assessments to the Washington Blueberry Commission can submit up to 30 free samples. Testing and results are confidential; only you and Phyto Diagnostics will know your results.  You can submit additional samples, but you’ll need to pay for them.

Start collecting samples once you begin to see symptoms in the field. BlShV symptoms often become apparent at the pink stage, while BlScV symptoms sometimes start later, around midbloom. Symptoms of the two are not usually distinguishable by eye though. Sample plants with symptoms, and a few nearby asymptomatic plants as well. 

Follow Phyto Diagnostics’ guidelines for sampling here. Briefly:

• Collect from plants representative of symptoms in the field. 
• For each sample, collect 5 live leaves from around a plant, choosing leaves close to symptoms when possible. Place the 5 leaves in a seal-able plastic bag. 
• Label the plant and the bag, so you can return to the plant once you have results. Use a simple, sequential numbering system for multiple samples. Label each bag with permanent marker on the bottom right corner.
• Keep samples dry, but fresh. Keep cool after collection; refrigerate if possible. Do not freeze.
• Arrange samples in sequential order, in groups of 10-20. Clip or staple the upper left hand corner. 
• Fill out Phyto Diagnostics’ Sample Submission Form, and include it with your samples. Keep a copy for yourself. 

You can either ship your samples overnight to Phyto Diagnostics or drop them off at one of three locations, where we will pick them up and ship them for you. If you choose to ship yourself, be sure to pack samples carefully according to Phyto Diagnostics’ directions, and include two copies of the appropriate Import Permit (the Blueberry Commission will make this available to growers). Samples have no commercial value, so be sure to indicate that to the shipper (Otherwise, Canadian Customs will levy charges on Phyto Diagnostics). 

You can drop samples off at any of three locations:

• Henry Bierlink, WRRC office, 204 Hawley Street, Lynden
• Chakradhar Mattupalli, WSU-NWREC16650 SR 536, Mt Vernon
• Alan Schreiber, WBC, 2621 Ringold Road, Eltopia

We will collect and ship from these locations May 6, May 20, June 3 and June 17.  Phyto Diagnostics generally provides results within two weeks of receipt.

If you have any questions about this program, please contact Tom Walters, Walters Ag Research: 360-420-2776, [email protected]