Effects of tree architecture on pollen dispersal and mating patterns in Abies pinsapo Boiss. (Pinaceae)

Plant architecture is crucial to pollination and mating in wind pollinated species. We investigate the effect of crown architecture on pollen dispersal, mating system and offspring quality, combining phenotypic and genotypic analyses in a low-density population of the endangered species Abies pinsapo. A total of 598 embryos from three relative crown height levels (bottom, middle, top) in five mother plants were genotyped using eleven nuclear microsatellite markers (nSSRs). Paternity analysis and mating system models were used to infer mating and pollen dispersal parameters. In addition, seeds were weighed (N = 16,110) and germinated (N = 736), and seedling vigour was measured to assess inbreeding depression. Overall, A. pinsapo shows a fat-tailed dispersal kernel, with an average pollen dispersal distance of 113–227 m, an immigration rate of 0.84–26.92%, and a number of effective pollen donors ranging between 3.5 and 11.9. We found an effect of tree height and relative crown height leve...