Dose-dependent selection drives lineage replacement during the experimental evolution of SDHI fungicide resistance in Zymoseptoria tritici

A - Papers appearing in refereed journals

Gutierrez-Alonso, O., Hawkins, N. J., Cools, H. J., Shaw, M. W. and Fraaije, B. A. 2017. Dose-dependent selection drives lineage replacement during the experimental evolution of SDHI fungicide resistance in Zymoseptoria tritici. Evolutionary Applications. 10 (10), pp. 1055-1066. https://doi.org/10.1111/eva.12511

AuthorsGutierrez-Alonso, O., Hawkins, N. J., Cools, H. J., Shaw, M. W. and Fraaije, B. A.
Abstract

Fungicide resistance is a constant threat to agricultural production worldwide. Molecular mechanisms of fungicide resistance have been studied extensively in the wheat pathogen Zymoseptoria tritici. However, less is known about the evolutionary processes driving resistance development. In vitro evolutionary studies give the opportunity to investigate this. Here, we examine the adaptation of Z. tritici to fluxapyroxad,a succinate dehydrogenase (Sdh) inhibitor. Replicate populations of Z. tritici derived from the sensitive isolate IPO323 were exposed to increasing concentrations of fluxapyroxad with or without UV mutagenesis. After ten increases in fungicide concentration, sensitivity had decreased dramatically, with replicate populations showing similar phenotypic trajectories. Sequencing the Sdh subunit B, C, and D encoding genes identified seven mutations associated with resistance to fluxapyroxad. Mutation frequency over time was measured with a pyrosequencing assay, revealing sequential lineage replacement in the UV-mutagenized populations but not in the untreated populations. Repeating selection from set time-points with different fungicide concentrations revealed that haplotype replacement of Sdh variants was driven by dose-dependent selection as fungicide concentration changed, and was not mutation-limited. These findings suggest that fungicide field applications may select for highly insensitive Sdh variants with higher resistance factors if the fungicide concentration is increased to achieve a better disease control. However, in the absence or presence of lower fungicide concentrations, the spread of these strains might be restricted if the underlying Sdh mutations carry fitness penalties.

Keywordsadaptation; agriculture; development and evolution; experimental
Year of Publication2017
JournalEvolutionary Applications
Journal citation10 (10), pp. 1055-1066
Digital Object Identifier (DOI)https://doi.org/10.1111/eva.12511
PubMed ID29151860
PubMed Central IDPMC5680630
Open accessPublished as ‘gold’ (paid) open access
FunderBiotechnology and Biological Sciences Research Council
Funder project or codeDelivering Sustainable Systems (SS) [ISPG]
Quantifying Sustainable Systems
Publisher's version
Output statusPublished
Publication dates
Online30 Jun 2017
Publication process dates
Accepted16 Jun 2017
PublisherWiley
Copyright licenseCC BY
ISSN1752-4571

Permalink - https://repository.rothamsted.ac.uk/item/8v5xw/dose-dependent-selection-drives-lineage-replacement-during-the-experimental-evolution-of-sdhi-fungicide-resistance-in-zymoseptoria-tritici

131 total views
58 total downloads
2 views this month
1 downloads this month
Download files as zip