Skip to main content
ARS Home » Northeast Area » Beltsville, Maryland (BARC) » Beltsville Agricultural Research Center » Mycology and Nematology Genetic Diversity and Biology Laboratory » People » Zafar Handoo » Nematode Extraction Procedures

Nematode Extraction Procedures
headline bar

Some Procedures for Collecting and Preparing Nematodes For Study.

Zafar A. Handoo and Donna Ellington

(Note: These procedures may be similar to or modified from those used by other workers.) 


Use of Sieves for Extraction of Nematodes From Soil

1. Materials: 1 bucket, 20 mesh sieve, 60 mesh sieve, 325 mesh sieve, and stand to hold sieves.

2. Procedure:

Note: These chemicals listed above are hazadous and should be handled properly!

3. Types of nematodes to collect from various sieves


Collecting Cyst-Forms from Greenhouse and Field Samples

1. Materials: 1 bucket, 20 mesh sieve, 60 mesh sieve, 325 mesh sieve (if collecting eel-shaped forms) and stand for sieves.

2. Procedure:

3. Types of nematodes to collect from various sieves


Cyst Cone Mounts (For Heterodera spp.)

1. Cut cyst in 3% formaldehyde.

2. Trim cyst cone portion (decide size so it can stand up well) in lactophenol or glycerine.

3. Transfer to water to remove above solutions.

4. Transfer to clove oil to remove water, air bubbles, and clean dirt off surface of cone. This clears cone.

5. Put a very tiny drop of clove oil on slide, put cone in this.

6. Put Euparal on round 12 mm coverslip and drop on top of cone in clove oil. Press down gently. If hard melt Euparal. (Heat slide so Euparal melts. Air bubbles will eventually come out and disappear.)

7. Check every day for the first week to make sure the cone is still standing. Get coverslip to lay on the vulva cone. If bubbles are inside the cone, turn the slide over and they will eventually squeeze out. Use round 12 mm coverglass.

Note: These chemicals listed above are hazardous and should be handled properly!


Modified Seinhorst (1959) Method of Taking Nematodes to Glycerin.

1. Make up two solutions to be used in the process and label.

2. Nemas should be hand picked with clean tools! Place nematodes in small deep dish (a Stender prep dish can be used which holds about 10 ml of solution) containing Solution #1 (about 75% of the volume of the dish). Both the dish and the solution must be extremely clean as any small particles will adhere to the specimens.

3. Place open small dish into larger closed glass vessel, eg. a desiccator, or staining dish, containing about 1/10 of its volume of 95% ethanol and leave the dish in this saturated atmosphere for at least 12 hours in an oven at 35 - 40C. This removes almost all the water and leaves the nematodes in a mixture of glycerol and ethanol.

4. Decrease the volume in small dish by about ? and add Solution #2 to the dish after the 12 hours.

5. Place small dish in covered petri dish and replace it in the oven.

6. Several hours later repeat step #5 (we've seen less collapsing of certain nematodes using this method).

7. Keep in covered petri dish in oven and add Solution #2 every day for a week. Then leave in the oven until the alcohol evaporates and the nematodes in the dish are in pure glycerol and can be mounted.

Note: These chemicals listed above are hazardous and should be handled properly!