How scent and nectar influence floral antagonists and mutualists

  1. Danny Kessler
  2. Mario Kallenbach
  3. Celia Diezel
  4. Eva Rothe
  5. Mark Murdock
  6. Ian T Baldwin  Is a corresponding author
  1. Max-Planck Institute for Chemical Ecology, Germany
  2. University of Pittsburgh, United States

Abstract

Many plants attract and reward pollinators with floral scents and nectar, respectively, but these traits can also incur fitness costs as they also attract herbivores. This dilemma, common to most flowering plants, could be solved by not producing nectar and/or scent, thereby cheating pollinators. Both nectar and scent are highly variable in native populations of coyote tobacco, Nicotiana attenuata, with some producing no nectar at all, uncorrelated with the tobacco's main floral attractant, benzylacetone. By silencing benzylacetone biosynthesis and nectar production in all combinations by RNAi, we experimentally uncouple these floral rewards/attractrants and measure their costs/benefits in the plant's native habitat and experimental tents. Both scent and nectar increase outcrossing rates for three, separately-tested, pollinators and both traits increase oviposition by a hawkmoth herbivore, with nectar being more influential than scent. These results underscore that it makes little sense to study floral traits as if they only mediated pollination services.

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Author details

  1. Danny Kessler

    Department of Molecular Ecology, Max-Planck Institute for Chemical Ecology, Jena, Germany
    Competing interests
    No competing interests declared.
  2. Mario Kallenbach

    Department of Molecular Ecology, Max-Planck Institute for Chemical Ecology, Jena, Germany
    Competing interests
    No competing interests declared.
  3. Celia Diezel

    Department of Molecular Ecology, Max-Planck Institute for Chemical Ecology, Jena, Germany
    Competing interests
    No competing interests declared.
  4. Eva Rothe

    Department of Molecular Ecology, Max-Planck Institute for Chemical Ecology, Jena, Germany
    Competing interests
    No competing interests declared.
  5. Mark Murdock

    University of Pittsburgh, Pennsylvania, United States
    Competing interests
    No competing interests declared.
  6. Ian T Baldwin

    Department of Molecular Ecology, Max-Planck Institute for Chemical Ecology, Jena, Germany
    For correspondence
    baldwin@ice.mpg.de
    Competing interests
    Ian T Baldwin, Senior editor, eLife.

Copyright

© 2015, Kessler et al.

This article is distributed under the terms of the Creative Commons Attribution License permitting unrestricted use and redistribution provided that the original author and source are credited.

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  1. Danny Kessler
  2. Mario Kallenbach
  3. Celia Diezel
  4. Eva Rothe
  5. Mark Murdock
  6. Ian T Baldwin
(2015)
How scent and nectar influence floral antagonists and mutualists
eLife 4:e07641.
https://doi.org/10.7554/eLife.07641

Share this article

https://doi.org/10.7554/eLife.07641

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