Nematode Management in Field Crops
ID
SPES-15NP (SPES-671NP)
The accuracy of your nematode assay results depends on the quality of the samples submitted.
Please follow the instructions below.
Types of Samples
Soil can be submitted for either a diagnostic or predictive nematode assay. Diagnostic assays are performed with the purpose of identifying the cause of poor growth in the current crop. Predictive assays determine the risk of next year’s crop being impacted by nematodes.
Predictive Samples
Predictive samples should be collected before planting or after harvest. Collect samples when the soil is moist but not waterlogged. If the crop to be planted or agronomic practices vary throughout the field, collect a separate sample from each area. If a field has multiple soil types, take a sample from each soil type.
Samples should be collected in a zig-zag pattern. (See Fig. 1 below). Thoroughly mix the composite sample in a plastic bucket and put a pint of soil in a plastic bag for submission to the nematode lab.
Diagnostic Samples
Collect samples when symptoms indicating a potential nematode problem are observed (e.g. patches of stunting or yellowing in the field).
Samples should be collected from areas with symptomatic plants, but NOT dead or dying plants. Additionally, a second sample from a “good” part of the field should be collected and submitted for comparison. Including samples of root/plant along with the soil is recommended and will aid in accurate diagnosis. (See Fig 2. below).
Preparing Samples
For both types of samples, place each sample in a labeled plastic bag, seal bag, and keep sample cool. Samples may be refrigerated up to one week prior to submission.
Submitting Samples
Complete the Nematode Assay Submission Form with as much information as possible to avoid a delay in processing results.
Submit form and samples by mail or in-person to:
Virginia Tech Tidewater AREC Nematode Diagnostic Lab
6321 Holland Road
Suffolk, Virginia, 23437
Questions?
Contact Dr. David Langston, Extension Plant Pathologist by e-mail vegpath@vt.edu.
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Publication Date
March 25, 2025
