Database Research Summaries2017 Sample Collection and Transportation Method Effects on Accuracy of Nematode Analysis in Mississippi Soybean Fields
Research Focus
The focus of this research is to demonstrate a lack of training among producers in how they should sample and to demonstrate how excessive heat during transportation reduces the accuracy of nematode analyses.
Objectives
- Compare and contrast nematode sampling techniques of “untrained” producer vs. “trained” Extension Specialist.
- Compare sample analyses via USPS Ground transportation vs. direct delivery by Extension Specialist.
Results
- All 5-test locations were sampled in late August/early September and samples were analyzed for nematode populations at the Nematology Laboratory at MSU. All samples were stored in an ice chest and delivered immediately to the nematode laboratory. Root knot, SCN juvenile, and SCN are the focus of results.
- Root knot: The Extension Specialist (ES)-collected samples saw significantly higher populations in 3 of 5 fields. The Grower (G)-collected samples showed higher populations in the remaining 2 fields but counts were low in these fields.
- SCN juvenile: ES collected sample was highest in only 1 field while the G collected sample was higher in 2 fields. The remaining 2 fields had zero counts for both grower and specialist-collected samples.
- SCN Cyst stage: ES collected sample was highest in 2 fields while the G collected sample was higher in 2 fields. The remaining field had identical counts.
- All 5-test locations were sampled in late August/early September and analyzed for nematode populations at the Nematology Laboratory at MSU. Each sample was divided into 3 subsamples: 0 hours in hot vehicle, 30 hours in hot vehicle, and 78 hours in hot vehicle. Root knot, SCN juvenile, and SCN Cyst stage are the focus of results.
- Root knot: Longer exposure in a hot vehicle led to 1 field increasing counts, 1 field decreasing counts, and 3 fields remaining fairly constant regardless of time in hot vehicle.
- SCN juvenile: Longer exposure in a hot vehicle led to 1 field increasing counts, 3 fields decreasing counts, and 1 field remaining fairly constant regardless of time in hot vehicle.
- SCN Cyst stage: Longer exposure in a hot vehicle had little effect on cyst counts.
Importance
- Farmers now know that advanced training would help recognize nematode symptomology but it does not translate into finding higher populations within that field.
- Farmers should submit a second sample to be tested if test results are negative but field symptomology such as stunting or yellowing suggests a possible nematode infestation.
For more information about this research project, please visit the National Soybean Checkoff Research Database.
Funded in part by the soybean checkoff.
