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 (LC₅₀ and LC₉₀) 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.

中文翻译：

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东方粘虫，Mythimna separata（鳞翅目：夜蛾科）幼虫和p对本地昆虫病原线虫的易感性

东方粘虫Mythimna separata Walker（鳞翅目：夜蛾科）是谷物作物的主要害虫，其暴发导致作物完全丧失。在这项研究中，我们测试致病性和土著线虫（公共组织）的生殖潜力异小籼稻Poinar，Karunakar，与大卫NBAIIH38，斯阿巴西Elawad NBAIISa01，S. carpocapsae韦泽NBAIISc05和S. siamkayai股票，Somsook和里德NBAIRS92反对实验室条件下分离支原体的幼虫期和p期。Steinernema carpocapsae导致二龄和四龄幼虫阶段的死亡率明显高于其他EPNs物种。Steinernema carpocapsae在幼虫期和greatest期造成的最大死亡率分别为100％和75％。在致死浓度值（LC观察显著差异₅₀和LC ₉₀针对不同阶段的EPN物质）粘虫。在EPNs物种中，在分离的M. separata的四龄幼虫阶段的渗透和繁殖方面存在差异。然而，需要进一步的研究来揭示EPN领域性能测试分离株被列入的IPM程序粘虫。