Susceptibility of Oriental armyworm, <i>Mythimna separata</i> (Lepidoptera: Noctuidae) larvae and pupae to native entomopathogenic nematodes
Jagadeesh Patil, Rangasamy Vijayakumar, Vaddar Linga, Sivakumar Gopalsamy
Abstract
Abstract The Oriental armyworm, Mythimna separata Walker (Lepidoptera: Noctuidae) is a major pest of cereal crops, and its outbreaks result in complete crop loss. In this study, we tested the pathogenicity and reproductive potential of indigenous entomopathogenic nematodes (EPNs), Heterorhabditis indica Poinar, Karunakar, & David NBAIIH38, Steinernema abbasi Elawad NBAIISa01, S. carpocapsae Weiser NBAIISc05 and S. siamkayai Stock, Somsook and Reid NBAIRS92 against larval and pupal stages of M. separata under laboratory conditions. Steinernema carpocapsae caused significantly greater mortality in second‐ and fourth‐instar larval stages than other EPNs species. Steinernema carpocapsae caused greatest mortality 100% in larval stages and 75% in pupal stages. Significant differences were observed in the lethal concentration values (LC 50 and LC 90 ) of EPNs species against different stages of M. separata . Differences in penetration and multiplication in the fourth‐instar larval stages of M. separata were observed amongst the EPNs species. However, further studies are needed to reveal the field performance of EPN isolates tested to be included in the IPM programme of M. separata .