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bioRxiv · 10.64898/2026.08.18.744459

Evolutionary history and polyploidization lead to rapid shifts in chemodiversity of Hypericum

Xiao, X.·Schweiger, R.·Stein, E. R.·Dussarrat, T.·Koch, M. A.·Mueller, C.
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Abstract

Polyploidization can profoundly affect plant metabolite biosynthesis, yet its influence on chemodiversity remains poorly understood, despite the central role of chemodiversity in mediating plant interactions with the environment. The coexistence of facultative apomictic and sexual reproductive systems across ploidy levels in Hypericum provides an excellent model for investigating the evolution of chemodiversity following polyploidization. We analyzed ploidy levels and leaf metabolic fingerprints across selected populations of three Hypericum taxa, H. maculatum, H. perforatum subsp. perforatum and H. perforatum subsp. veronense. Polyploidization was common across all three taxa. Leaf metabolic fingerprints were more pronouncedly differentiated by the ploidy level of the mother plant (F0) than that of the offspring (F1). Although unique metabolic features emerged in plants of most ploidy levels, diploid plants exhibited fewer metabolic features than polyploid plants. Higher Shannon diversity, functional Hill diversity, and intensities of features belonging to specific chemical families were associated with higher F0 ploidy levels in H. perforatum subsp. perforatum, but not in H. maculatum and H. perforatum subsp. veronense. Our findings demonstrate that polyploidization can lead to rapid shifts in chemodiversity across generations in Hypericum. The fast divergence in chemodiversity associated with polyploidization in H. perforatum may contribute to its remarkable invasive potential.

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Xiao, X., Schweiger, R., Stein, E. R., Dussarrat, T., Koch, M. A., Mueller, C.. 2026-08-22. Evolutionary history and polyploidization lead to rapid shifts in chemodiversity of Hypericum. https://doi.org/10.64898/2026.08.18.744459

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