Spatio-temporal control of mutualism in legumes helps spread symbiotic nitrogen fixation
Abstract
Mutualism is of fundamental importance in ecosystems. Which factors help to keep the relationship mutually beneficial and evolutionarily successful is a central question. We addressed this issue for one of the most significant mutualistic interactions on Earth, which associates plants of the leguminosae family and hundreds of nitrogen (N2)-fixing bacterial species. Here we analyze the spatio-temporal dynamics of fixers and non-fixers along the symbiotic process in the Cupriavidus taiwanensis-Mimosa pudica system. N2-fixing symbionts progressively outcompete isogenic non-fixers within root nodules, where N2-fixation occurs, even when they share the same nodule. Numerical simulations, supported by experimental validation, predict that rare fixers will invade a population dominated by non-fixing bacteria during serial nodulation cycles with a probability that is function of initial inoculum, plant population size and nodulation cycle length. Our findings provide insights into the selective forces and ecological factors that may have driven the spread of the N2-fixation mutualistic trait.
Article and author information
Author details
Funding
Agence Nationale de la Recherche (ANR-12-ADAP-0014-01)
- Marta Marchetti
- Catherine Masson-Boivin
- Delphine Capela
Institut National de la Recherche Agronomique
- Benoit Daubech
Max Planck society
- Chaitanya S Gokhale
Agence Nationale de la Recherche (ANR-16-CE20-0011-01)
- Marta Marchetti
- Catherine Masson-Boivin
- Delphine Capela
Agence Nationale de la Recherche (ANR-10-LABX-41)
- Benoit Daubech
- Marta Marchetti
- Cécile Pouzet
- Marie-Christine Auriac
- Catherine Masson-Boivin
- Delphine Capela
Agence Nationale de la Recherche (ANR-11-IDEX-0002-02)
- Benoit Daubech
- Marta Marchetti
- Cécile Pouzet
- Marie-Christine Auriac
- Catherine Masson-Boivin
- Delphine Capela
The funders had no role in study design, data collection and interpretation, or the decision to submit the work for publication.
Reviewing Editor
- Wenying Shou, Fred Hutchinson Cancer Research Center, United States
Version history
- Received: May 17, 2017
- Accepted: October 11, 2017
- Accepted Manuscript published: October 12, 2017 (version 1)
- Version of Record published: November 15, 2017 (version 2)
Copyright
© 2017, Daubech 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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