How maize root volatiles affect the efficacy of entomopathogenic nematodes in controlling the western corn rootworm?

Ivan Hiltpold, Stefan Toepfer, Ulrich Kuhlmann & Ted Turlings

Résumé Because the ferocious maize pest Diabrotica virgifera virgifera LeConte can adapt to all currently used control strategies, focus has turned to the development of novel, more sustainable control methods, such as biological control using entomopathogenic nematodes (EPN). A good understanding of the biology and behaviour of these potential control agents is essential for their successful deployment. Root systems of many maize varieties emit (E)-beta-caryophyllene (E beta C) in response to feeding by larvae of the beetle D. v. virgifera. This sesquiterpene has been shown to attract certain species of EPN, thereby enhancing their control potential. In this study, we tested the effect of this root-produced volatile on the field efficacy of the three EPN Heterorhabditis bacteriophora, Heterorhabditis megidis and Steinernema feltiae against D. v. virgifera larvae in southern Hungary. By comparing beetle emergence and root damage for two maize varieties, one that emits E beta C and one that does not, it was found that root protection by H. megidis and S. feltiae was higher on the emitting variety, but this was not the case for H. bacteriophora. Overall, all three nematode species showed good control potential. We conclude that, if properly applied and in combination with the right maize variety, the release of these nematodes can be as effective as other control methods.
Mots-clés Heterorhabditis megidis, Heterorhabditis bacteriophora, Steinernema, feltiae, Diabrotica virgifera virgifera, Zea mays, Tritrophic, interaction, Crop protection, Biological control, Root exudates, Nematode attraction, virgifera-virgifera coleoptera, induced plant odors, zea-mays l., parasitic wasps, transgenic corn, natural enemies, insect hosts, chrysomelidae, attraction, herbivores
Citation Hiltpold, I., Toepfer, S., Kuhlmann, U., & Turlings, T. (2010). How maize root volatiles affect the efficacy of entomopathogenic nematodes in controlling the western corn rootworm?. Chemoecology, 20(2), 155-162.
Type Article de périodique (Anglais)
Date de publication 2010
Nom du périodique Chemoecology
Volume 20
Numéro 2
Pages 155-162