author(s)
Sooraj S, Nisha MS and Anitha N

abstract
A survey was conducted in Thiruvananthapuram, Kollam and Pathanamthitta districts of Kerala during July, 2017 to isolate indigenous entomopathogenic nematodes (EPNs) from different crop habitats viz. vegetables, banana and coconut through random sampling and to determine the potential of indigenous EPNs in causing mortality of tobacco caterpillar, Spodoptera litura (Fabricius). A total of forty soil samples were collected from rhizosphere region of different crop habitats and three native isolates of EPNs were obtained. The infectivity of indigenous isolates to tobacco caterpillar was assessed at an inoculum level of 300 infective juveniles (IJs) and Isolate 2 showed highest mortality (29.99 per cent) and maximum emergence of IJs (3.5x10⁵) at 24 h after treatment. Results of pathogenicity of native EPN isolates against tobacco caterpillar at inoculum levels of 10, 50, 100 and 200 IJs revealed that Isolate 2 @ 200 IJs recorded highest mortality of tobacco caterpillar (80.52 and 99.35 per cent at 60 and 72 HAT respectively). Based on morphological characters, Isolate 2 was identified as Metarhabditis rainai which can be exploited successfully for the management of tobacco caterpillar.