Genetic mapping; Secondary metabolites; Hybridization; Adaptive introgression; Evolution
Caseys Celine, Caseys Celine, Stritt Christoph, Glauser Gaetan, Blanchard Thierry, Lexer Christian, Lexer Christian (2015), Effects of hybridization and evolutionary constraints on secondary metabolites: The genetic architecture of phenylpropanoids in European Populus species, in
PLoS ONE, 10(5), 1.
Bock Dan G., Caseys Celine, Cousens Roger D., Hahn Min A., Heredia Sylvia M., Hübner Sariel, Turner Kathryn G., Whitney Kenneth D., Rieseberg Loren H. (2015), What we still don't know about invasion genetics, in
Mol Ecol, 2277.
Todesco M. Pascual M. A. Owens G. L. Ostevik K. L. Moyers B. T. Hübner S. Heredia S. M., Hybridization and extinction, in
Evolutionary applications.
Hybridization is a widespread phenomenon in plants and animals that mix genomes of related species through reproduction. The recombination of different genomes provides potential for phenotypic and genomic diversification. In some cases, this diversification gives populations the necessary variability to adapt to novel or extreme habitat and contributes to plant adaptation but also plant invasiveness. Among functional traits believed to contribute to plant adaptation, secondary metabolites involved in biotic and abiotic interactions represent excellent candidate for adaptive introgression. This exchange of beneficial genetic material between hybridizing species is of first importance to understand plant evolution. Secondary metabolites have a great diversity among plant kingdom, with chemical compounds specific to plant genus or even species. This diversity is generally explained by their role in response to environmental pressures and insect resistance. However, hybridization was shown to increase chemical variability and diversity and to occasionally lead to synthesis of novel compounds specific to hybrids. Even though the phenotypic effects of hybridization on secondary metabolites are well established, their genetic architecture remains poorly known. The objectives of this project are manifold following the diversity generated in sunflower hybrids Helianthus a. texanus from phenotypes to genotypes. First, we aim to chase effects of hybridization on the synthesis of secondary metabolites in three hybrid lineages and over multiple generations in field conditions. The chemical differentiation between parental species and hybrids but also between hybrids lineages will provide insights into the potential of phenotypic innovation of hybridization. Secondly, the genetic architecture of secondary metabolites will be examined by genetic mapping and lead to identification of quantitative trait loci (QTL). The comparison of genetic markers in hybrids and parental species will reveal if specific QTL have crossed the species boundary. Studying the relation between chemical traits and herbivore damages will assess the potential for adaptive introgression of these QTL. Overall, this project will constitute a step towards a better understanding of the ecological effects and evolutionary consequences of hybridization.