Entomopathogenic nematodes as models for inundative biological control. In: Nematodes as Model Organisms

Authors: Shapiro Ilan, David; HAZIR, SELCUK - Aydin Adnan Menderes University; GLAZER, ITAMAR - Agricultural Research Organization, Volcani Center

Submitted to: Nematodes as Model Organisms
Publication Type: Book / Chapter
Publication Acceptance Date: 5/1/2021
Publication Date: 6/25/2022
Citation: Shapiro-Ilan, D.I., Hazir, S. and Glazer, I. 2022. Entomopathogenic nematodes as models for inundative biological control. In: Glazer, I., Shapiro-Ilan, D.I., Sternberg, P.W., editors. Nematodes as Model Organisms. Wallingford, UK: CABI. p. 293-308.

Interpretive Summary: Chemical pesticides can pose threats to humans, and wildlife, and might have an adverse impact on the environment or cause secondary pest outbreaks. Strategies that rely on natural or biological pest control can be safer to the environment and have low risk of secondary pest outbreaks. Entomopathogenic nematodes are small round worms that are safe to humans and the environment. These beneficial nematodes are used as natural bio-pesticides. However, the efficacy of entomopathogenic nematodes can be limited by the organisms’ sensitivity to environmental extremes (such as temperature and UV radiation) or deficiencies in host-finding, virulence (killing power) or other biocontrol traits. Deficiencies in desirable traits can be overcome through genetic improvement. In this chapter we summarize the progress in genetic improvement in beneficial nematodes. We present the different approaches that can be used toward genetic improvement and provide a series of case studies for improving nematode efficacy and commercial suitability. We also include a section on the importance of maintaining trait stability in the culturing and improvement of EPN. Genetic improvement can be implemented via discovery of new superior strains, genetic selection, hybridization or transgenic methods. Trait stability can be maintained through the creation of selected homozygous lines. Combinations of genetic improvement and trait stability methods will lead to improved biological control and enhance sustainable crop production.

Technical Abstract: Chemical pesticides can pose threats to humans, and wildlife, and might have an adverse impact on the environment or cause secondary pest outbreaks. Strategies that rely on biological control agents can be safer to the environment and have low risk of secondary pest outbreaks. Entomopathogenic nematodes from the families Steinernematidae and Heterorhaditidae are among the most potent biocontrol agents. These nematodes are applied to control a wide array of economically important pests. However, the efficacy of entomopathogenic nematodes can be limited by the organisms’ sensitivity to environmental extremes (such as temperature and UV radiation) or deficiencies in host-finding, virulence or other biocontrol traits. Deficiencies in desirable traits can be overcome through genetic improvement. In this chapter we summarize the progress in genetic improvement in steinernematids and heterorhabditids. We present the different approaches that can be used toward genetic improvement and provide a series of case studies for improving nematode efficacy and commercial suitability. We also include a section on the importance of maintaining trait stability in the culturing and improvement of EPN. Genetic improvement can be implemented via discovery of new superior strains, genetic selection, hybridization or transgenic methods. Trait stability can be maintained through the creation of selected homozygous lines. Combinations of genetic improvement and trait stability methods will lead to improved biological control and enhance sustainable crop production.