Question

The apparatus used for the extraction of cysts from soil is:

• A. Cobb’s sieve
• B. Fenwick can
• C. Oostenbrink elutriator
• D. Baermann’s funnel

Hint:

Oostenbrink elutriator uses water flow and sedimentation for nematode extraction from soil.

Answer 1

The Correct Option is C

Step 1: Cobb's sieve and Baermann's funnel isolate motile nematodes, not cysts, so both are ruled out.
Step 2: The Fenwick can floats cysts only from small, clean samples, not bulk soil.
Step 3: The Oostenbrink elutriator separates particles by size and density using water-air flow, suited for bulk cyst extraction.
Step 4: The correct answer is Oostenbrink elutriator.