Local Adaptation in Plants

Abstract

AbstractLocal adaptation reflects the fact that local populations tend to have a higher mean fitness in their native environment than in other environments and in other populations introduced in their home site. Starting in the 1920s a large number of reciprocal transplant and common garden experiments, as well as studies of populations along environmental clines, have demonstrated that local adaptation is widespread in plants. One remaining challenge is to understand how populations become locally adapted and to characterise the genes involved in this process. Theoretically, local selection at single loci will promote local adaptation and gene flow will decrease it. For quantitative traits, the situation is more complex, and strong local adaptation can even be established and maintained in the presence of higher gene flow. The genetic basis of local adaptation will evolve through time, and eventually trade‐offs between alleles at a locus may occur in the different environments (antagonistic pleiotropy).Key ConceptsLocal adaptation is widespread in plants but its genetic basis is still poorly known.Local adaptation is the property of a group of populations in a given set of environments.Local adaptation depends primarily on the balance between selection and migration.The genetic architecture of local adaptation, in particular the presence of trade‐offs, is likely to be variable among species as it will depend, among other things, on the time since the populations diverged or the amount of gene flow between them.