Test Overview
Duration: Variable
Wash and soak tests are used to detect certain seedborne fungi and nematodes. These methods are particularly useful when the target organism or fungal structures can be removed from the seed or released through soaking and identified by microscopic examination.
The method used depends on the crop and target organism.
Test Details
Wash Tests
Wash tests are primarily used to detect fungal spores present on the surface of seed.
Seeds are agitated in water to remove spores and other material from the seed surface. The resulting suspension is concentrated and examined microscopically for structures characteristic of the target fungus.
Soak Tests
Soak tests are used for certain nematodes and internally seedborne fungi, including some downy mildews and loose smut.
Seeds are soaked to release the target organism or to allow internal seed structures to be examined. Depending on the test, nematodes may be recovered from the soaking solution and examined microscopically, or seed tissues may be prepared and examined for fungal structures.
Sample Requirements
Sample requirements vary considerably depending on the crop, target organism, and testing protocol.
Typically, 400–10,000 seeds may be required for wash tests and 400–30,000 seeds for soak tests.
Contact Customer Care if you are unsure of the amount of seed required for your specific test.
Additional seed may be required when multiple tests are requested on the same sample.