Selection of entomopathogenic nematodes for enhanced responsiveness to a volatile root signal helps to control a major root pest
Ivan Hiltpold, Mariane Baroni, Stefan Toepfer, Ulrich Kuhlmann & Ted Turlings
| Résumé |
The efficacy of natural enemies as biological control agents against
insect pests can theoretically be enhanced by artificial selection
for high responsiveness to foraging cues. The recent discovery that
maize roots damaged by the western corn rootworm (WCR) emit a key
attractant for insect-killing nematodes has opened the way to
explore whether a selection strategy can improve the control of
root pests. The compound in question, (E)-beta-caryophyllene, is
only weakly attractive to Heterorhabditis bacteriophora, one of the
most infectious nematodes against WCR. To overcome this drawback, we
used a six-arm below-ground olfactometer to select for a strain of
H. bacteriophora that is more readily attracted to
(E)-beta-caryophyllene. After six generations of selection, the
selected strain responded considerably better and moved twice as
rapidly towards a (E)-beta-caryophyllene source than the original
strain. There was a minor trade-off between this enhanced
responsiveness and nematode infectiveness. Yet, in subsequent field
tests, the selected strain was significantly more effective than the
original strain in reducing WCR populations in plots with a maize
variety that releases (E)-beta-caryophyllene, but not in plots with
a maize variety that does not emit this root signal. These results
illustrate the great potential of manipulating natural enemies of
herbivores to improve biological pest control. |
| Mots-clés |
entomopathogenic nematode, tritrophic interaction, artificial selection, biological control, Diabrotica virgifera virgifera, western corn, rootworm, western corn-rootworm, diabrotica-virgifera-virgifera, heterorhabditis-bacteriophora, genetic-improvement, steinernema-feltiae, natural enemies, coleoptera, maize, chrysomelidae, tolerance |
| Citation | Hiltpold, I., Baroni, M., Toepfer, S., Kuhlmann, U., & Turlings, T. (2010). Selection of entomopathogenic nematodes for enhanced responsiveness to a volatile root signal helps to control a major root pest. Journal of Experimental Biology, 213(14), 2417-2423. |
| Type | Article de périodique (Anglais) |
| Date de publication | 2010 |
| Nom du périodique | Journal of Experimental Biology |
| Volume | 213 |
| Numéro | 14 |
| Pages | 2417-2423 |