Data from: Heritable variation in root secondary metabolites is associated with recent climate

1. Plants can adapt to changing environments by adjusting the production
and maintenance of diverse sets of bioactive secondary metabolites. To
date, the impact of climatic conditions relative to other factors such as
soil abiotic factors and herbivore pressure on the evolution of plant
secondary metabolites is poorly understood, especially for plant roots. 2.
We explored associations between root latex secondary metabolites in 63
Taraxacum officinale populations across Switzerland and climatic
conditions, soil abiotic parameters, root herbivore pressure and cytotype
distribution. To assess the contribution of environmental effects, root
secondary metabolites were measured in F0 plants in nature and F2 plants
under controlled greenhouse conditions. 3. Concentrations of root latex
secondary metabolites were most strongly associated with climatic
conditions, while current soil abiotic factors or root herbivore pressure
did not show a clear association with root latex chemistry. Results were
similar for natural and controlled conditions, suggesting heritable
variation rather than environmental plasticity as underlying factor. 4.
Synthesis. We conclude that climatic conditions likely play a major role
in the evolution of root secondary metabolites. These results may hint at
a novel role of root latex metabolites in tolerance of abiotic stress.