Ploidy level and genome size (GS) could affect the invasive capacity of plants, although these parameters can be contradictory. While small GS seems to favor dispersion, polyploidy-which increases the GS-also seems to favor it. Using a phylogenetic path analysis, we evaluated the effects of both factors on the environmental tolerance and invasive success of plants. We selected 99 invasive plant species from public online databases and gathered information about invasive capacity (number of non-original countries in which each species occurs), tolerance to environmental factors, ploidy level, and GS. The invasive capacity varied depending on the ploidy level and tolerance to environmental factors. Polyploids and species with increased tolerance to elevated temperatures and rainfall values exhibited high invasive capacity. We found no evidence that GS affects the invasive capacity of plants. We suggest that the genetic variability provided by polyploidization has a positive impact on plant competitiveness, which may ultimately lead to an increased ability to colonize new environments. In a global warming scenario, integrative approaches using phenotypic, genetic, epigenetic, and ecological traits should be a productive route to unveil the aspects of invasive plants.
Keywords: Abiotic factors; Alien species; Climate change; Ecological tradeoff; Invasiveness; Polyploidy.