Evidence map›Paper›PMID 18296628›Full record

ArticleThe Plant cell2008

A maize (E)-beta-caryophyllene synthase implicated in indirect defense responses against herbivores is not expressed in most American maize varieties.

Tobias G Köllner, Matthias Held, Claudia Lenk, Ivan Hiltpold, Ted C J Turlings, Jonathan Gershenzon, Jörg Degenhardt

Open access · bronzeAbstract read
In one paragraph

Article in The Plant cell, 2008. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Cited by 175 papers.

0numbers the graph read from it
0cells of the map it votes in
175citing papers in PubMed
22.8field-weighted citation impact, top 1% of its field
1 · What the graph read from it

What it found

Each row is one number read from the abstract, on the scale the paper reported it, with its interval. Left of the dashed line favours the treatment, right favours the comparator. Under each row is the sentence it came from. New to these charts? A ten-minute tutorial.

The abstract states no effect estimate the extractor could read, or names no intervention and outcome on the map, so this paper lights no cell and moves no belief. It is still indexed, cited and linked below.

2 · The registry

The trial behind it

Trials whose registry record cites this paper, or whose number appears in the abstract. A trial that started after this paper was published is citing it as background, not reporting it.

Neither the registry nor the abstract names a trial number. If this is a trial report, that itself is worth knowing.

3 · Its place in the literature

Who cites it

175 citing papers in PubMed, 453 citations in OpenAlex.

  1. Underground Signals: The Ecological Power of Root Volatiles.Advanced science (Weinheim, Baden-Wurttemberg, Germany) · 2026
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  11. Airborne β-caryophyllene disrupts virus-vector mutualism by priming tomato defenses.Proceedings of the National Academy of Sciences of the United States of America · 2026
    Article
  12. Article
  13. Review
  14. Discovery of a defence-response gene forFrontiers in plant science · 2026
    Article
  15. Article
  16. Review
  17. Article
  18. Article
  19. Article
  20. Review

115 more citing papers are in PubMed but not listed here.

4 · The record

Corrections and comments

5 · Who and what money

Authors and funding

7 authors at 2 institutions in 2 countries.

Tobias G KöllnerMax Planck Institute for Chemical Ecology, D-07745 Jena, Germany.
Matthias Held
Claudia Lenk
Ivan Hiltpold
Ted C J Turlings
Jonathan Gershenzon
Jörg Degenhardt
Max Planck Institute for Chemical Ecology · DEUniversity of Neuchâtel · CH

Funding

No grant is acknowledged in the PubMed record.

6 · The paper itself

Abstract

The sesquiterpene (E)-beta-caryophyllene is emitted by maize (Zea mays) leaves in response to attack by lepidopteran larvae like Spodoptera littoralis and released from roots after damage by larvae of the coleopteran Diabrotica virgifera virgifera. We identified a maize terpene synthase, Terpene Synthase 23 (TPS23), that produces (E)-beta-caryophyllene from farnesyl diphosphate. The expression of TPS23 is controlled at the transcript level and induced independently by D. v. virgifera damage in roots and S. littoralis damage in leaves. We demonstrate that (E)-beta-caryophyllene can attract natural enemies of both herbivores: entomopathogenic nematodes below ground and parasitic wasps, after an initial learning experience, above ground. The biochemical properties of TPS23 are similar to those of (E)-beta-caryophyllene synthases from dicotyledons but are the result of repeated evolution. The sequence of TPS23 is maintained by positive selection in maize and its closest wild relatives, teosinte (Zea sp) species. The gene encoding TPS23 is active in teosinte species and European maize lines, but decreased transcription in most North American lines resulted in the loss of (E)-beta-caryophyllene production. We argue that the (E)-beta-caryophyllene defense signal was lost during breeding of the North American lines and that its restoration might help to increase the resistance of these lines against agronomically important pests.

Indexed as

Alkyl and Aryl TransferasesAmino Acid SequenceAnimalsChromatography, GasGene Expression Regulation, EnzymologicGene Expression Regulation, PlantHydrogen-Ion ConcentrationImmunity, InnateLarvaLepidopteraMolecular Sequence DataMolecular StructurePlant DiseasesPlant LeavesPlant ProteinsPlant RootsAlkyl and Aryl Transferasescaryophyllenefarnesyl pyrophosphatePlant ProteinsPolycyclic SesquiterpenesPolyisoprenyl PhosphatesSesquiterpenesterpene synthase

Identifiers

PMID18296628
PMCPMC2276456
OpenAlexW2152447906

What OpenQuestion holds

Textmetadata
Read underepoch 390

Registered trials

None linked

Read under generation 80e0d062 · epoch 390. Bibliography from PubMed, PubMed Central and OpenAlex; grants from NIH RePORTER; trial links from ClinicalTrials.gov; estimates, votes and beliefs from the OpenQuestion graph.