Syndromes in suites of correlated traits suggest multiple mechanisms facilitating invasion in a plant range-expander

Various mechanisms can facilitate the success of plant invasions simultaneously, but may be difficult to disentangle. We compared plants of the range-expanding species Bunias orientalis from populations of native, invasive and exotic, not yet invasive origin in a field common garden over two years. Plants were grown under two nitrate-regimes and multiple traits regarding growth, defence, antagonist loads and reproduction were measured. We used a rank-based clustering approach to assign correlated traits to distinct suites. These suites were analysed for “syndromes” that are expressed as a function of population origin and/or fertilisation treatment and might represent different invasion mechanisms. Indeed, distinct suites of traits were differentially affected by these factors. Our results suggest that different pre-adaptation properties, such as certain growth characteristics and intraspecific chemical variation, as well as post-introduction adaptations to antagonists and resource avai...