Symptom evolution following the emergence of maize streak virus
Abstract
For pathogens infecting single host species evolutionary trade-offs have previously been demonstrated between pathogen-induced mortality rates and transmission rates. It remains unclear, however, how such trade-offs impact sub-lethal pathogen-inflicted damage, and whether these trade-offs even occur in broad host-range pathogens. Here, we examine changes over the past 110 years in symptoms induced in maize by the broad host-range pathogen, maize streak virus (MSV). Specifically, we use the quantified symptom intensities of cloned MSV isolates in differentially resistant maize genotypes to phylogenetically infer ancestral symptom intensities and check for phylogenetic signal associated with these symptom intensities. We show that whereas symptoms reflecting harm to the host have remained constant or decreased, there has been an increase in how extensively MSV colonizes the cells upon which transmission vectors feed. This demonstrates an evolutionary trade-off between amounts of pathogen-inflicted harm and how effectively viruses position themselves within plants to enable onward transmission.
Data availability
All data and R code used for analyses in this study are available on the following public repository:https://github.com/sdellicour/msv_symptom_evolution
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Data From: Symptom evolution following the emergence of maize streak virusGitHub, msv_symptom_evolution.
Article and author information
Author details
Funding
Swedish Institute (00448/2014)
- Adérito L Monjane
European Union (PIOF-GA-2013-622571)
- Philippe Roumagnac
European Research Council (725422-ReservoirDOCS)
- Philippe Lemey
Fonds Wetenschappelijk Onderzoek (G066215N)
- Philippe Lemey
Fonds Wetenschappelijk Onderzoek (G0D5117N)
- Philippe Lemey
Fonds Wetenschappelijk Onderzoek (G0B9317N)
- Philippe Lemey
Fonds De La Recherche Scientifique - FNRS (-)
- Simon Dellicour
Fonds Wetenschappelijk Onderzoek (-)
- Simon Dellicour
South African National Research Foundation (-)
- Kehinde A Oyeniran
The World Academy of Sciences (-)
- Kehinde A Oyeniran
European Union: European Regional Development Found (-)
- Pierre Lefeuvre
Conseil Regional de la Reunion (-)
- Pierre Lefeuvre
Centre de Coopération Internationale en Recherche Agronomique pour le Développement (-)
- Pierre Lefeuvre
South African National Research Foundation (TTK1207122745)
- Gordon W Harkins
The funders had no role in study design, data collection and interpretation, or the decision to submit the work for publication.
Copyright
© 2020, Monjane 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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