In vitro cost-effective culture technique for pure line production of facultative nematode parasites of insects and free-living nematodes

. Four nematode isolates, Acrobeloides spp. (isolates HNK19, HNK25), Metarhabditis sp. (HNK22) and Distolabrellus sp. (isolate HNK26), were recovered from the soils of different agriculture fields of Noida and Meerut regions of India. Pure line populations of these isolates were obtained through a new method, i.e., agar trap technique, and then these populations were used to test the efficiency of this technique for mass culture of facultative nematode parasites of insects and free-living nematodes. This technique was also compared with the universal nematode mass culture method using the larvae of Galleria mellonella. Results of the present study revealed that all the isolates grew faster on agar trap rather than on Galleria larvae. At day 20 post-inoculation, the highest and lowest nematode yield in agar trap was recorded as 2.54 x 105 nematodes (trap)-1 and 3.9 x 104 nematodes (trap)-1 in HNK25 and HNK22, respectively, as compared to the Galleria method, the highest and lowest nematode yield was recorded as 2.19 x 104 nematodes (larva)-1 and 1.25 x 103 nematodes (larva)-1 in HNK25 and in HNK26, respectively.