author(s)
Aasha, Ashok Kumar Chaubey and Aashaq Hussain Bhat

abstract
Three populations (DS4, DS6 and DS7) of entomopathogenic nematodes were isolated from the agricultural lands of district Meerut of western Uttar Pradesh, India. Morphological characters especially presence of horn like structures on labial region indicated that the strains were closely related to the “bicornutum” group’ of Steinernema spp. The nematodes were conspecific to Steinernema abbasi based on morphology, morphometric and molecular analysis. The morphology was similar to the type population with only difference being the presence of mucron in second generation male not observed in original population. The analysis of ITS rDNA sequences revealed that at positions, 211 and 407, T and A are present in studied strains while in the type species, AY230158 two unambiguous sequences Y and R are present at same locations. No difference was observed in D2-D3 domain of 28S rRNA. The Indian strains were also tested positively for its virulence against four major pests, namely, Galleria mellonella, Helicoverpa armigera, Spodoptera litura and Holotrichia serrata with good efficacy on the virulence except H. serrata. Strain DS7 was more pathogenic compared with other two strains with LD50 values of 7.28, 5.65 and 17.65 IJs, respectively against G. mellonella, H. armigera and S. litura.