Nematode Extraction Methods: Root Extraction Techniques

1. Nematode Extraction Methods:Root Extraction Techniques Kavitha Govindasamy Jimmy R.Rich Maria L .Mendes

2. A Plant-Parasitic Nematode

3. Sampling for Nematodes Sampling and extracting for nematodes serves two purposes: • Diagnosis a current problem • Predict a future problem

4. Objectives of sampling and extracting nematodes Identify the nematode Population estimation Diagnose a nematode disease Make management decisions Regulatory purposes Research and surveys

5. Some Common Nematode Extraction Methods • Root Samples Jar incubation and sieving Blending and sieving • Soil samples Baermann funnel Modified Baermann funnel • Foliar samples Punching and incubating Scissors technique

6. Root Extraction Techniques:Jar Method Principle • Nematodes are extracted based on their active migration from roots

7. Materials required • Glass jars and caps • 325 or finer mesh sieve • Labels and rubber bands • Dark chamber

8. Sample ready for processing

9. Wash the roots

10. Damp dry the roots

11. Weigh the damp-dried roots

12. Place roots in jars, add water

13. Place jars in tray

14. Store in the dark for 72 hours

15. Following incubation, remove from storage and add water

16. Collect nematodes on sieve

17. Rinse nematodes from sieve

18. Nematode samples ready for observation

19. Advantages and Limitations Advantages • Extracts migratory endoparasitic nematodes • Few materials needed • Simple procedure to follow Limitations • Not useful for ectoparasitic nematodes • Lack of aeration can be a problem • Sieves are needed to concentrate nematodes

20. Root Extraction Techniques:Blending and Sieving Principle • Nematodes are released from roots due to maceration.

21. Materials required • Blender • 40 and 325 or 500 mesh sieves • Pan or bowl • Wire mesh • Filter paper • Squeeze bottle • Weighing balance • Scissors

22. Wash roots well

23. Cut roots

24. Damp dry the roots

25. Weigh roots

26. Place roots into blender, cover roots with water

27. Blend at low speed for 10-20 seconds

28. Pour the roots into 325 or finer mesh sieve

29. Set up a Baermann tray

30. Place filter paper on the Baermann tray

31. Add water to Baermann tray

32. Transfer the blended roots into the filter paper

33. Incubate for 24 hours

34. Remove roots from the pan

35. Pour the water in the dish through a 325 or fine mesh sieve

36. Concentrate nematodes for observation

37. Advantages and Limitations Advantages • Fast method to extract nematodes from roots • Foliar nematodes can also be easily extracted Limitations • Chemicals released from the roots can be injurious to nematodes • Blending for long time may damage nematodes

38. 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

39. For additional information or comments, please contact: • Kavitha_nem@yahoo.com • jimmyr@ufl.edu • mlmendes@ufl.edu