Abstract Detail

Nº613/1429 - Applying genomics and metabolomics to elucidate evolution in the homoploid complex of Baccharis L. in Chile
Format: ORAL
Authors
Fabian Schneider1, Olga Zafra Delgado2, Tobias G. Kllner2, Frank H. Hellwig1
Affiliations
1 Friedrich-Schiller-University, Jena, Germany 2 Max Planck Institute for Chemical Ecology, Jena, Germany
Abstract
The genus Baccharis L. (Asteraceae-Astereae) in Chile is supposed to form a homoploid complex containing about 21 taxa and 33 described hybrids based on morphological and ecological evidence. In this study, we investigated evolutionary processes within this complex using genomic and metabolomic approaches with Baccharis linearis (Ruiz et Pavn) Pers., B. macraei Hook. et Arn., B. vernalis F.H. Hellwig and their putative hybrid B. x intermedia DC. in Central Chile. The sampling covered selected populations ranging from La Serena in the north to Concepcin in the south. Next generation sequencing (ddRad/Illumina) and untargeted metabolomics (LC-qTOF) was performed using silicagel-dried material. The initial hypothesis on the hybrid nature of B. intermedia was corroborated by genomic and chemical evidence. Within the morphologically intermediate hybrid, a combination of genetic markers from both parents could be detected. The hybrid shows a significantly higher heterozygosity than both parental taxa. Moreover, metabolomics analyses revealed that B. intermedia has a mixed chemotype and combines the chemistry of the parental species. Both parents exhibit a north-south genetic differentiation that goes in parallel with their chemistry. This pattern is also found in the hybrid pointing to its polytopic origin. There is evidence for gene flow between the hybrid and the parental species, albeit at a low level, allowing independent evolution of the hybrid taxon. Time and history of the taxa involved are discussed in the light of ecology vegetation history.