The products of a single maize sesquiterpene synthase form a volatile defense signal that attracts natural enemies of maize herbivores
Christiane Schnee, Tobias G Kollner, Matthias Held, Ted Turlings, Jonathan Gershenzon & Joerg Degenhardt
| Résumé |
Plants can defend themselves against herbivores by attracting
natural enemies of the herbivores. The cues for attraction are
often complex mixtures of herbivore-induced plant volatiles, making
it difficult to demonstrate the role of specific compounds. After
herbivory by lepidopteran larvae, maize releases a mixture of
volatiles that is highly attractive to females of various parasitic
wasp species. We identified the terpene synthase TPS10 that forms
(E)-beta-farnesene, (E)-alpha-bergamotene, and other
herbivory-induced sesquiterpene hydrocarbons from the substrate
farnesyl diphosphate. The corresponding gene is expressed in
response to herbivore attack and is regulated at the transcript
level. Overexpression of tps10 in Arabidopsis thaliana resulted in
plants emitting high quantities of TPS10 sesquiterpene products
identical to those released by maize. Using these transgenic
Arabidopsis plants as odor sources in olfactometer assays showed
that females of the parasitoid Cotesia marginiventris learn to
exploit the TPS10 sesquiterpenes to locate their lepidopteran hosts
after prior exposure to these volatiles in association with hosts.
This dissection of the herbivore-induced volatile blend
demonstrates that a single gene such as tps10 can be sufficient to
mediate the indirect defense of maize against herbivore attack. |
| Mots-clés |
parasitoid attraction, plant defense signal, terpene biosynthesis, volatile terpenes, TERPENOID METABOLISM, PARASITIC WASPS, PREDATORY MITE, ARABIDOPSIS, EMISSION, PLANTS, IDENTIFICATION, BIOSYNTHESIS, VARIABILITY, GENE |
| Citation | Schnee, C., Kollner, T. G., Held, M., Turlings, T., Gershenzon, J., & Degenhardt, J. (2006). The products of a single maize sesquiterpene synthase form a volatile defense signal that attracts natural enemies of maize herbivores. Proceedings of the National Academy of Sciences of the United States of America, 103(4), 1129-1134. |
| Type | Article de périodique (Anglais) |
| Date de publication | 2006 |
| Nom du périodique | Proceedings of the National Academy of Sciences of the United States of America |
| Volume | 103 |
| Numéro | 4 |
| Pages | 1129-1134 |