Abstract:
Understanding why some plant species become invasive remains a central question in invasion ecology. Two nonexclusive explanations are often proposed: invasion success may result from enhanced growth and reproductive performance or from biochemical novelty that alters plant interactions in new environments. To test these alternatives, we compared growth performance and metabolic profiles of native and non-native populations of Anthemis cotula L. grown under common conditions. Morphological traits, including root and shoot length, biomass allocation, and capitula production, did not differ significantly between native and non-native plants, indicating similar growth performance across ranges. In contrast, untargeted metabolomics revealed clear differences in metabolic richness and composition. Non-native plants exhibited a higher number of detected molecular features, particularly in belowground compartments. Root exudates showed the strongest divergence, with non-native plants displaying greater metabolic richness and a distinct compositional profile. Multivariate analysis confirmed significant differentiation in root exudate chemistry, whereas leaves and flowers remained largely conserved. Despite these compositional shifts, Hill diversity and evenness metrics for both unannotated and identified metabolites showed no significant differences between ranges, suggesting a similar overall diversity structure. Annotation revealed largely conserved chemical classes, dominated by flavonoids in above-ground tissues and amino acids in roots, with subtle enrichment of fatty acids, terpenes, and amino acids in non-native root exudates. Overall, our findings indicate that invasion success in A. cotula is associated less with enhanced growth than with targeted reconfiguration of belowground metabolic traits, especially root exudate chemistry, which may support altered rhizosphere interactions in novel environments.