Efficiency of different methods of extracting the rice root nematode Hirschmanniella oryzae from rice and wheat soil and root samples

The nematode extraction method of centrifugal-floatation proved to be more efficient and significant (p ≤ 0.01) in extracting the rice root nematode, Hirschmanniella oryzae adults and larvae from soil or roots of rice and wheat crops than those extracted by sieving and tissue paper filtration technique. The extracted nematode from rice roots using incubation method is time-dependent and the peak of nematodes occurred four days after incubation. The number of extracted nematode varied according to crop, nematode mobility in soil particles, the number of nematodes present and tissue paper permeability.