Multiple alleles at a single locus control seed dormancy in Swedish Arabidopsis
- Vienna Biocenter, Austria
Abstract
Seed dormancy is a complex life history trait that determines the timing of germination and is crucial for local adaptation. Genetic studies of dormancy are challenging, because the trait is highly plastic and strongly influenced by the maternal environment. Using a combination of statistical and experimental approaches, we show that multiple alleles at the previously identified dormancy locus DELAY OF GERMINATION1 jointly explain as much as 57% of the variation observed in Swedish Arabidopsis thaliana, but give rise to spurious associations that seriously mislead genome-wide association studies unless modeled correctly. Field experiments confirm that the major alleles affect germination as well as survival under natural conditions, and demonstrate that locally adaptive traits can sometimes be dissected genetically.
Data availability
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Low coverage sequencing of three A. thaliana F2 populations for QTL mappingPublicly available at the NCBI BioProject (accession no: PRJNA343766).
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Low coverage sequencing of A. thaliana samples from Swedish field experimentsPublicly available at the NCBI BioProject (accession no: PRJNA343768).
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Massive genomic variation and strong selection in Arabidopsis thaliana lines from SwedenPublicly available at Github (https://github.com).
Article and author information
Author details
Funding
European Research Council (268962 (MAXMAP))
- Magnus Nordborg
The funders had no role in study design, data collection and interpretation, or the decision to submit the work for publication.
Copyright
© 2016, Kerdaffrec 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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