Suitability of mulberry silkworm, Bombyx mori and root grub. Holothchia serrata was tested for in vivo mass production of Steinernema glaseri and an unidentified species of Heterorhabditis along with the standard host Galleria mellonelia in GKVK, UAS, Banagalore. Karnataka. B. mori was found to be the most appropriate host for the production of S. glasen and Heterorhabditis sp. nematodes @ 1191032.6 and 8807110.9 IJs/rupee, respectively. G. mellonelia was the next best alternative which produced 983611.5 and 5080930.8 IJs/rupee of S glaseri and Heterorhabditis sp., respectively. H. serrata was the least suitable host which yielded 896038.7 and 128399.8 IJs/ rupee of Heterorhabditis sp. and S. glaseri. respectively. Therefore, the mulberry silkworm which is available throughout the year in karnataka is more suitable as it can be obtained directly from the rearing room at low cost. In other states G. mellonelia may be a better host.