Evaluation of entomopathogenic nematodes for the management of white grub, Leucopholis lepidophora Blanchard (Coleoptera: Scarabaeidae)

Abstract

The native strains of entomopathogenic nematode (EPNs) were evaluated against arecanut white grub, Leucopholis lepidophora Blanchard during 2015 -17 at two locations viz., Koluru (Thirtahalli taluk) and Harakere (Shivamogga taluk) villages of Shivamogga district of Karnataka, India. Field trials were conducted under All India Coordinated Research Project (AICRP) on Palms to identify the suitable eco friendly management measures. The imposition of aqua formulation of EPN, Steinernema carpocapsae (CPCRI-SC1) @ 60 lakh IJs/palm during June - July followed by combined application with insecticide imidacloprid 17.8 SL @ 0.0045% during September - October was caused 96.6% and 92.5% reduction in grub population in farmers field at Koluru and Harakere village respectively over pretreatment grub population followed by EPN alone application of S. carpocapsae caused 74.3% and 79.1% and talc formulation of H. indica caused 54.8% and 51.7% reduction in grub population in the respective villages. The standard insecticide imidacloprid 17.8 SL @ 0.0045% caused a reduction of 77.3% and 80.8% in the respective villages during the period of treatment. The palms treated with EPN and imidacloprid had showed the better emergence of new roots indicates suppression of grub population in the palms root zone and increase in the number of leaves and overall improvement in the palms growth and yield indicates effective uptake of inputs by the palms over untreated palms. It was concluded that EPN can be used as one of the component in IPM of arecanut white grubs with imidacloprid for its effective management in arecanut.