Little Cherry Disease Diagnostic Testing

The ELISA lab is currently under reduced operations due to the COVID19 epidemic, please do not submit samples for little cherry testing.


1. Collecting Samples

If you are intending to conduct molecular testing for the X-disease phytoplasma or Little cherry virus 2, the type of tissue you would need to submit changes depending on the time of year – because the pathogen moves as the plant grows and develops.

When Symptoms are Observed

If you are observing what looks like little cherry disease symptoms on the tree, or limbs of a tree, and want to confirm what you are seeing: submit four to six-inch cuttings from the diseased limb, including leaves and if possible, the peduncle (fruit stem).

When Symptoms are not Yet Observed

If you do not have little cherry disease symptoms on a tree, it becomes a little bit more difficult. Take a total of 4-5 samples from around the tree, from the following tissues, depending on the time of year:

Dormant/delayed dormancy: Dormant wood (4-6 inch cuttings). Not recommended for X-disease.

Bloom: New wood, flower buds, emerging leaves, flower stems. Not recommended for X-disease.

Pre-harvest: Fruit stems and 4-6” stem sections from current year’s growth.

Early Postharvest: Fully expanded leaves (4-5 leaves each, include the petiole) and 4-6” stem sections from current year’s growth.

Pre-dormancy: Fully expanded leaves (before leaf drop) (4-5 leaves each, include the petiole) and 4-6” stem sections from current year’s growth.

2. Submitting Samples

All samples should be collected and placed in a Ziploc bag and kept in a cooler or refrigerator until you can send them to a lab. If mailing or couriering plant samples, please place a cooler pack in with the samples to keep them in good condition.

Next, enter your sample information using the online form and include a copy with the samples. Either drop the samples off at Prosser or send them overnight mail in a Styrofoam shipping container with an icepack (Please avoid sending samples on Thursday or Friday, and do not ship samples of wet ice). Samples should be sent to:

Diagnostic Lab
Attn.: Tina Vasile
WSU Irrigated Agriculture Research and Extension Center
24106 N Bunn Rd. Prosser WA 99350

The contact for the lab is Tina Vasile (509) 786-9382 ( should you have any questions or need further information.