The western corn rootworm (Diabrotica virgifera virgifera) is a very serious pest of corn in the North America and Europe. Larvae of this insect exclusively feed on maize roots, often causing plant lodging whereas adults may reduce yields through silk feeding and interfering maize pollination. Insect-parasitic Heterorhabditid and Steinernematid nematodes have been applied for the control of D. v. virgifera larvae in the fields. Heterorhabditis bacteriophora is proved to be as effective as pyrethroid insecticide, tefluthrin in reducing over 65% emergence adults of rootworms. Application of tefluthrin in combination with Steienernema carpocapsae can result in a synergistic response that can lead to increased mortality of rootworms by 24%. Also, entomopathogenic nematodes including Steinernema glaseri, Steinernema arenarium, Steinernema abassi and Heterorhabdtis bacteriophora when applied at the rate of 8-16 nematodes per cm2 under laboratory condtions caused over 77% larval mortality.
For more information on corn rootworms and entomopathogenic nematode interactions, read following literature
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Jackson, J.J. 1996. Field performance of entomopathogenic nematodes for suppression of western corn rootworm (Coleoptera: Chrysomelidae). J Econ Entomol 89:366–372.
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Jackson, J.J., Brooks, M.A. 1995. Parasitism of western corn rootworm larvae and pupae by Steinernema carpocapsae. J Nematol 27:15–20.
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Toepfer, S., Gueldenzoph, C. Ehlers, R.U. and Kuhlmann, U. 2005. Screening of entomopathogenic nematodes for virulence against the invasive western corn rootworm, Diabrotica virgifera virgifera (Coleoptera: Chrysomelidae) in Europe. Bulletin of Entomological Research. 95: 473- 482.