Vignette d'image

Hiltpold, Ivan

Nom
Hiltpold, Ivan
Affiliation principale
Identifiants
https://libra.unine.ch/handle/123456789/605

Résultat de la recherche

Filtres

22
2
Réinitialiser les filtres

Paramètres

Voici les éléments 1 - 2 sur 2
  • Publication
    Accès libre
    Restoring a maize root signal that attracts insect-killing nematodes to control a major pest
    (2009)
    Degenhardt, Jörg
    ;
    Hiltpold, Ivan 
    ;
    Köllner, Tobias G.
    ;
    Frey, Monika
    ;
    Gierl, Alfons
    ;
    Gershenzon, Jonathan
    ;
    Hibbard, Bruce E.
    ;
    Ellersieck, Mark R.
    ;
    Turlings, Ted 
    When attacked by herbivorous insects, plants emit volatile compounds that attract natural enemies of the insects. It has been proposed that these volatile signals can be manipulated to improve crop protection. Here, we demonstrate the full potential of this strategy by restoring the emission of a specific belowground signal emitted by insect-damaged maize roots. The western corn rootworm induces the roots of many maize varieties to emit (E)-β-caryophyllene, which attracts entomopathogenic nematodes that infect and kill the voracious root pest. However, most North American maize varieties have lost the ability to emit (E)-β-caryophyllene and may therefore receive little protection from the nematodes. To restore the signal, a nonemitting maize line was transformed with a (E)-β-caryophyllene synthase gene from oregano, resulting in constitutive emissions of this sesquiterpene. In rootworm-infested field plots in which nematodes were released, the (E)-β-caryophyllene-emitting plants suffered significantly less root damage and had 60% fewer adult beetles emerge than untransformed, nonemitting lines. This demonstration that plant volatile emissions can be manipulated to enhance the effectiveness of biological control agents opens the way for novel and ecologically sound strategies to fight a variety of insect pests.
  • Publication
    Accès libre
    Recruitment of entomopathogenic nematodes by insect-damaged maize roots
    (2005)
    Rasmann, Sergio 
    ;
    Köllner, Tobias G.
    ;
    Degenhardt, Jörg
    ;
    Hiltpold, Ivan 
    ;
    Toepfer, Stefan
    ;
    Kuhlmann, Ulrich
    ;
    Gershenzon, Jonathan
    ;
    Turlings, Ted 
    Plants under attack by arthropod herbivores often emit volatile compounds from their leaves that attract natural enemies of the herbivores. Here we report the first identification of an insect-induced belowground plant signal, (E)-β-caryophyllene, which strongly attracts an entomopathogenic nematode. Maize roots release this sesquiterpene in response to feeding by larvae of the beetle Diabrotica virgifera virgifera, a maize pest that is currently invading Europe. Most North American maize lines do not release (E)-β-caryophyllene, whereas European lines and the wild maize ancestor, teosinte, readily do so in response to D. v. virgifera attack. This difference was consistent with striking differences in the attractiveness of representative lines in the laboratory. Field experiments showed a fivefold higher nematode infection rate of D. v. virgifera larvae on a maize variety that produces the signal than on a variety that does not, whereas spiking the soil near the latter variety with authentic (E)-β-caryophyllene decreased the emergence of adult D. v. virgifera to less than half. North American maize lines must have lost the signal during the breeding process. Development of new varieties that release the attractant in adequate amounts should help enhance the efficacy of nematodes as biological control agents against root pests like D. v. virgifera.