Isolation, Identification and Pathogenicity of Native Entomopathogenic Nematode Strains Collected from Hyderabad, Telangana State in India

Abstract

Entomopathogenic nematodes (EPNs) are a promising alternative to integrated biocontrol control agent in many agricultural crop pests. Isolation and identification of indigenous species of entomopathogenic nematodes are necessary for successful implementation in the IPM (integrated pests management) program. The study was aimed to isolate native entomopathogenic nematode strain under genus Steinernema and Heterorhabditis in Hyderabad region to determine their potential control of sugarcane root grub (Holotrichia serrata), cotton and vegetable crops pod borer (Helicoverpa armigera), leaf-eating caterpillar (Spodoptera litura), potato cutworm (Agrotis segitum) etc. Hundred sixty soil samples were collected in 11 communities during the period Sep., 2016 to March 2017, in that 33 samples were found to be positive for EPNs. All the isolates were selected for their apparent of pathogenicity against the greater wax moth, Galleria mellonella. Seventeen samples of the genus Steinernema and sixteen samples of Heterorhabditis were isolated in the same geographical region of various crop ecosystems. The native isolates of KN EPNH1 (Heterorhabditis indica) and KN EPNS17 (Steinernema carpocapsae) found to be highly virulent and more pathogenic effect to the major borer pests of sugarcane, cotton, vegetable, potato and groundnut resulting lowest lethal dosages and lethal times. These entomopathogenic nematodes carrying symbiotic bacteria represent one of the best non-chemical strategies for insect control. Infective juveniles (IJs) of Heterorhabditidae and Steinernematidae nematodes actively seek the host in the soil which is employed as biocontrol agents. The study of population dynamics of entomopathogenic nematodes is fundamental to understanding their persistence, distribution and effect on insect populations for the development of predictive models for the control programmes.