Reproductive assurance through self-fertilization does not vary with population size in the alien invasive plant Datura stramonium

摘要: Autonomous self-fertilization is suggested to be associated with invasiveness in plants because it offers reproductive assurance when there a shortage of suitable mates or pollinators. Given that shortages and pollinators are common cause Allee effects small plant populations, we predict the benefits terms should greatest populations. We tested this idea for invasive herb Datura stramonium, self-fertilizing species which also cross-pollinated some extent by insects (mainly hawkmoths honeybees). During two consecutive years, studied 20 55 respectively, different sizes. Untreated flowers D. stramonium showed high levels fruit seed set all populations studied. Although, were generally reduced about 90% was prevented through emasculation, effect did not vary according population size. By using natural color (anthocyanin) dimorphism 12 average outcrossing rate low (1.3%) no relationship between Pollen removal from size, suggesting pollinator visitation lower However, decreasing deviations observed expected size imply may have an increased chance extinction due demographic stochasticity. Overall, our results suggest important stages establishment, just founder population.