Indian Journal of Entomology Online published (Preview) DoI No.: IN VIVO EVALUATION OF INDIGENOUS STRAIN OF HETERORHABDITIS INDICA AGAINST HOLOTRICHIA SERRATA Swati, Jagpal Singh*, Riazuddin, Rinni SahRawat and Seema Rani Foundation for Agriculture Resources Management and Environmental Remediation (FARMER) Shastri Nagar, Ghaziabad 201002, Uttar Pradesh *Email: jps.farmer@gmail.com (corresponding author) ABSTRACT The root feeding white grub of Holotrichia serrata F. causes serious damage in sugarcane, groundnut and maize, and entomopathogenic nematodes (EPNs) are effective against this pest. In the present study the native strain of EPN Heterorhabditis indica (MK078602) was isolated from village Sabitgarh, Bulandshahar district in Uttar Pradesh. Its effcacy was evaluated against H. serrata under laboratory conditions. Infective Juveniles in selected concentrations (0, 100, 200, 300 and 400 IJs/larva of H. rhabdita in 100g were applied to the 1 st and 2 nd instar grubs using surface soil incorporation method. LD 50 and LD 90 values were analyzed at different time inoculation. The results revealed maximum mortality with LD 50 of 89.601 and LD 90 of 226.200 for 1 st instar; and LD 50 115.050 and LD 90 722.164 IJs for 2 nd instar after 168 hr of inoculation at the minimum dose (IJs/ grub). Key words: Entomopathogenic nematode, Heterorhabditis indica, sugarcane, white grub, Holotrichia serrata, bioassay, effcacy 20032-- Swati, Jagpal Singh Holotrichia serrata F. (Coleoptera: Scarabaeidae) is a serious root feeder grub of sugarcane, groundnut and maize and distributed in the several districts of Uttar Pradesh, Rajasthan, Haryana, Madhya Pradesh, Andhra Pradesh, Tamil Nadu, Karnataka, Maharashtra, Gujarat and West Bengal. Heterorhabditis indica (Nematoda: Rhabditida) is a heat tolerant species of entomopathogenic nematodes (EPNs) and is found to parasitic many soil insect pests >25 o C. This benefcial nematode parasite of insects also uses a cruiser- type of foraging strategy to fnd their insect hosts. Infective juveniles of H. indica carry hundreds of cells of symbiotic bacteria (Photorhabdus luminescens) in their gut and this microfora becomes the weapon to kill their insect hosts. Evidently the native strain of EPN is more suitable for managing soil insect pests because of higher adaptation to local climate and other population regulating microbial fora (Bedding, 1990). Present studies evaluate the effcacy of native strain of H. indica isolated from village Sabitgarh, Bulandshahar district in Uttar Pradesh against H. serrata predominant species of white grub under laboratory conditions. This ecofriendly alternative can be included as an essential aspect in Integrated Pest Management strategies of major crops. MATERIALS AND METHODS The native strain of H. indica (MK078602) isolated from village Sabitgarh, Bulandshahr district in Uttar Pradesh was used. This EPN strain was multiplied inside ffth instar larvae of wax moth Galleria mellonella. The infective juveniles (IJs) emerging from the Galleria cadaver were collected in 0.01% formalin water (Shapiro et al. 2006) by using White’s trap and stored in darkness at 10-15 0 C under further use for 2 weeks. Before being used for bioassay, IJs were allowed to acclimatize at room temperature for one hr and their viability checked by observing movements under Leica S9i stereozoom microscope. H. serrata adult beetles were collected from host trees, viz., Neem (Azadiracta indica), Sheesham (Dalbergia sissoo), Guvava (Psidium guajava) from Dabana village, Ghaziabad using light trap. The collected mated female beetles were placed in desiccators containing moist soil for oviposition and monitored for eggs on alternate days. The collected eggs were transferred to petridishes containing moist soil. The newly emerged neonates were transferred individually on live maize roots and reared individually up to pupation in controlled conditions (30±2 0 C, 70±5% RH, 12:12 hr Scotophase- photoperiod). Grub mortality bioassay was carried out in individual plastic pot (6 cm deep and 3 cm dia) by using soil incorporation method. The sterilized sandy soil (autoclaved at 121°C under 15 PSI before use) was adjusted by 25% moisture by adding distilled water. 100, 29 July-2020