ISOLATION AND IDENTIFICATION OF ENTOMOPATHOGENIC NEMATODES: BIOLOGICAL POTENTIAL AGAINST LEPIDOPTERAN AND COLEOPTERAN PESTS.

The use of entomopathogenic nematodes (families: Heterorhabditidae and Steinernematidae) against various insect pests has grown rapidly in recent years and around 100 valid species of entomopathogenic nematodes have been identified from different countries of the world. In this context, the present study aimed to isolate and identify entomopathogenic nematodes from local soil in Uttar Pradesh, India; and have been evaluated for their efficacy against lepidopteran and coleopteran larvae. Totally 28 samples were found positive (14 %) from 200 soil samples collected for entomopathogenic nematodes isolation and on the basis of molecular characterization, three were identified as Heterorhabditis indica, Steinernema abbasi, and Steinernema siamkayai. In controlled conditions, they were evaluated against the fifth instar larva of Galleria mellonella and the first and second instar grubs of Holotrichia serrata. The lowest ED50 (IJs/larva) value was recorded at 48 h for H. indica (ED50 4.603) followed by Steinernema abbasi (ED50 7.118) and S. siamkayai (ED50 10.663) against G. mellonella. Further, the most effective strain of H. indica was tested against 1st and 2nd stage grubs H. serrata and ED50 of 130.798 and 263.104 were recorded, respectively. In the present study, the native strains of entomopathogenic nematodes evaluated against the larval stage of lepidopteran and coleopteran pests and found more suitable against local pests because of adaptation to local climate; these confined bioagents may serve as a viable option for pest control in organic farming. [ABSTRACT FROM AUTHOR]