Experimental admixture among geographically disjunct populations of an invasive plant yields a global mosaic of reproductive incompatibility and heterosis

作者：Ramona-Elena Irimia, José L. Hierro, Soraia Branco, Gastón Sotes, Lohengrin A. Cavieres, Özkan Eren, Christopher J. Lortie, Kris French, Ragan M. Callaway, Daniel Montesinos · 发表于：Journal of Ecology · 年份：2021 · DOI：10.1111/1365-2745.13628 · 被引用次数：26 · 研究领域：Plant and animal studies、Ecology and Vegetation Dynamics Studies、Animal Ecology and Behavior Studies

Abstract Invasive species have the ability to rapidly adapt in the new regions where they are introduced. Classic evolutionary theory predicts that the accumulation of genetic differences over time in allopatric isolation may lead to reproductive incompatibilities resulting in decreases in reproductive success and, eventually, to speciation. However, experimental evidence for this theoretical prediction in the context of invasive species is lacking. We aimed to test for the potential of allopatry to determine reproductive success of invasive plants, by experimentally admixing genotypes from six different native and non‐native regions of Centaurea solstitialis , an invasive forb for which preliminary studies have detected some degree of reproductive isolation between one native and non‐native region. We grew plants under common garden conditions and outcrossed individuals originating from different source populations in the native and introduced range to evaluate reproductive success in terms of seed to ovule ratio produced. We also assessed geographical and genetic isolation among C . solstitialis regions as a potential driving factor of reproductive success. Experimental admixture generated mixed fitness effects, including significant increases, decreases and no differences in reproductive success as compared to crosses within population (control). Centaurea solstitialis invasive populations in the Americas generated preponderantly negative fitness interactions, regardless o...