nematode extraction methods: baermann funnel and modified baermann techniques kavitha govindasamy...
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Nematode Extraction Methods:Baermann Funnel and Modified Baermann Techniques
Kavitha GovindasamyJimmy R.RichMaria L .Mendes
A Plant-Parasitic Nematode
Sampling for Nematodes
Sampling and extracting of nematodes serves two purposes
Diagnosis a current problem Predict a future problem
Objectives of sampling and extraction
Nematode identification Population estimation Diagnose a nematode disease Make management decisions Regulatory purposes Research and surveys
Some Common Nematode Extraction Methods
Soil samples Baermann funnel Modified Baermann funnel Root Samples Jar incubation and sieving Blending and sieving Foliar samples Punching and incubating Scissors technique
Soil Extraction Techniques: Baermann Funnel
Principle
Extraction based on the active movement of the nematodes (motility dependent method)
Materials required
Funnel Funnel stand Wire mesh Tissue paper/ coffee filter Rubber or plastic tube Clamp or spring clip Beaker or vial Plastic drink cup cover
Baermann Funnel set up
Soil sample over wire mesh
Funnel
Beaker
Clamp
Rubber tubing
Clamp to hold funnel
Begin Baermann funnel setup
Add the soil sample to the coffee filter or tissue paper
Place the sample on the funnel
Cover the tissue over the soil
Incubate for 48 hours and collect the nematodes
Collect nematodes in a beaker
Advantages and Limitations
Advantages Recovery of clean, live samples Sieves not needed Inexpensive to constructLimitations Not effective for inactive nematodes Recovery percentages may be low
Modified Baermann Funnel Baermann trays (Whitehead & Hemming’s modification, 1964)
Principle
Extraction based on the active migration of the nematodes (motility dependent method)
Materials required
Pan or tray Wire mesh Tissue paper, coffee filter Squeeze bottle 500 mesh sieve
Add water to the dish
Place soil on tissue paper
Place tissue paper on the wire mesh
Fold the tissue over soil, add water
Completed technique, ready for incubation
Incubate at room temperature for 3 days
Following incubation, remove wire mesh from the dish
Pour water into sieve
Rinse nematodes from the sieve
Advantages and Limitations
Advantages Recovery of clean, live samples Inexpensive to construct Materials readily available
Limitations Fine soil particles cloud sample Lack of aeration can be a problem Sieves are needed to concentrate
nematodes
Acknowledgments Janete Brito, Department of Plant Industry, Gainesville,
Florida Frank Woods, Nematode Assay Lab, University of
Florida, Gainesville, Florida Joey Orajay, Entomology and Nematology Department,
University of Florida, Gainesville, FL
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