Variable opportunities for outcrossing result in hotspots of novel genetic variation in a pathogen metapopulation
- University of Zürich, Switzerland
- Université de Lyon, France
- University of Helsinki, Finland
- Aalto University, Finland
Abstract
Many pathogens possess the capacity for sex through outcrossing, despite being able to reproduce also asexually and/or via selfing. Given that sex is assumed to come at a cost, these mixed reproductive strategies typical of pathogens have remained puzzling. While the ecological and evolutionary benefits of outcrossing are theoretically well-supported, support for such benefits in pathogen populations are still scarce. Here, we analyze the epidemiology and genetic structure of natural populations of an obligate fungal pathogen, Podosphaera plantaginis. We find that the opportunities for outcrossing vary spatially. Populations supporting high levels of coinfection -a prerequisite of sex - result in hotspots of novel genetic diversity. Pathogen populations supporting coinfection also have a higher probability of surviving winter. Jointly our results show that outcrossing has direct epidemiological consequences as well as a major impact on pathogen population genetic diversity, thereby providing evidence of ecological and evolutionary benefits of outcrossing in pathogens.
Data availability
All data and scripts used to perform the analyses presented in this paper are available in the git repository at https://github.com/ComputerBlue/FungalSex.git.
Article and author information
Author details
Funding
European Research Council (281517)
- Anna-Liisa Laine
European Research Council (724508)
- Anna-Liisa Laine
Academy of Finland (296686)
- Anna-Liisa Laine
The funders had no role in study design, data collection and interpretation, or the decision to submit the work for publication.
Copyright
© 2019, Laine 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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Variable opportunities for outcrossing result in hotspots of novel genetic variation in a pathogen metapopulation
eLife 8:e47091.
https://doi.org/10.7554/eLife.47091
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