Virulence of four entomopathogenic nematodes against the tobacco cutworm Spodoptera litura Fabricius

• Published in: Biological control 2020-11, Vol.150, p.104348, Article 104348
• Main Authors: Acharya, Rajendra, Yu, Yeon-Su, Shim, Jae-Kyoung, Lee, Kyeong-Yeoll
• Format: Article
• Language: English
• Subjects: Biological control; Control efficacy; Entomopathogenic nematodes; Penetration; Reproduction
• ISSN: 1049-9644; 1090-2112
• DOI: 10.1016/j.biocontrol.2020.104348

•Entomopathogenic nematodes are useful biocontrol agents for the control of Spodoptera litura.•EPNs induced higher mortality of younger larvae than older ones of S. litura.•EPNs induced higher rates of penetration and reproduction in older larvae than younger larvae of S. litura.•Heterorhabditis indica, Steinernema carpocapsae, and S. longicaudum were more susceptible than H. bacteriophora in S. litura. Spodoptera litura Fabricius is a polyphagous pest that is seriously affecting various crops. Controlling S. litura in the fields is a challenging task due to its high resistance to most chemical pesticides. Entomopathogenic nematodes (EPNs) have been used as biological control agents against S. litura, but little information is known about their virulence. Here we compared the virulence of four EPNs, namely Heterorhabditis bacteriophora, H. indica, Steinernema carpocapsae, and S. longicaudum against each larval stage of S. litura. All EPNs caused more lethality in younger larvae than in older larvae. The mortality at all larval stages was proportional to EPN exposure time and density. The comparison among four EPNs showed that H. indica, S. carpocapsae, and S. longicaudum were associated with higher mortality, penetration rate, and reproduction rate than H. bacteriophora. These EPNs also effectively controlled S. litura in a pot assay. Our findings indicate that H. indica, S. carpocapsae, and S. longicaudum can be used as efficient biological control agents against S. litura.