title: Non-density dependent pollen dispersal of Shorea maxwelliana (Dipterocarpaceae) revealed by a Bayesian mating model based on paternity analysis in two synchronized flowering seasons.
abstract: Pollinator syndrome is one of the most important determinants regulating pollen dispersal in tropical tree species. It has been widely accepted that the reproduction of tropical forest species, especially dipterocarps that rely on insects with weak flight for their pollination, is positively density-dependent. However differences in pollinator syndrome should affect pollen dispersal patterns and, consequently, influence genetic diversity via the mating process. We examined the pollen dispersal pattern and mating system of Shorea maxwelliana, the flowers of which are larger than those of Shorea species belonging to section Mutica which are thought to be pollinated by thrips (weak flyers). A Bayesian mating model based on the paternity of seeds collected from mother trees during sporadic and mass flowering events revealed that the estimated pollen dispersal kernel and average pollen dispersal distance were similar for both flowering events. This evidence suggests that the putative pollinators - small beetles and weevils - effectively contribute to pollen dispersal and help to maintain a high outcrossing rate even during sporadic flowering events. However, the reduction in pollen donors during a sporadic event results in a reduction in effective pollen donors, which should lead to lower genetic diversity in the next generation derived from seeds produced during such an event. Although sporadic flowering has been considered less effective for outcrossing in Shorea species that depend on thrips for their pollination, effective pollen dispersal by the small beetles and weevils ensures outcrossing during periods of low flowering tree density, as occurs in a sporadic flowering event.
authors.affiliation: School of Life and Environmental Sciences, University of Tsukuba, Tsukuba, Ibaraki, Japan.
authors.forename: Shinsuke
authors.initials: S
authors.lastname: Masuda
authors.affiliation: Forestry Division, Japan International Research Center for Agricultural Sciences, Tsukuba, Ibaraki, Japan ; Forestry Biotechnology Division, Forest Research Institute Malaysia, Kepong, Selangor Darul Ehsan, Malaysia.
authors.forename: Naoki
authors.initials: N
authors.lastname: Tani
authors.affiliation: Department of Forest Genetics, Forestry and Forest Products Research Institute, Tsukuba, Japan.
authors.forename: Saneyoshi
authors.initials: S
authors.lastname: Ueno
authors.affiliation: Forestry Biotechnology Division, Forest Research Institute Malaysia, Kepong, Selangor Darul Ehsan, Malaysia.
authors.forename: Soon Leong
authors.initials: SL
authors.lastname: Lee
authors.affiliation: Forestry Biotechnology Division, Forest Research Institute Malaysia, Kepong, Selangor Darul Ehsan, Malaysia.
authors.forename: Norwati
authors.initials: N
authors.lastname: Muhammad
authors.affiliation: Graduate School for International Development and Cooperation, Hiroshima University, Higashi-Hiroshima, Hiroshima, Japan.
authors.forename: Toshiaki
authors.initials: T
authors.lastname: Kondo
authors.affiliation: Faculty and Graduate School of Urban Environmental Sciences, Tokyo Metropolitan University, Hachioji, Tokyo, Japan.
authors.forename: Shinya
authors.initials: S
authors.lastname: Numata
authors.affiliation: School of Life and Environmental Sciences, University of Tsukuba, Tsukuba, Ibaraki, Japan ; Department of Forest Genetics, Forestry and Forest Products Research Institute, Tsukuba, Japan.
authors.forename: Yoshihiko
authors.initials: Y
authors.lastname: Tsumura
mesh_terms: D000465:Algorithms; D000818:Animals; D001499:Bayes Theorem; D001517:Coleoptera / Q000502:physiology; D018744:DNA, Plant / Q000235:genetics; D053958:Dipterocarpaceae / Q000033:anatomy & histology / Q000235:genetics / Q000502:physiology*; D005426:Flight, Animal; D035264:Flowers / Q000033:anatomy & histology / Q000502:physiology; D014644:Genetic Variation; D018895:Microsatellite Repeats; D008954:Models, Biological; D011058:Pollen / Q000502:physiology*; D054817:Pollination / Q000235:genetics / Q000502:physiology; D012098:Reproduction / Q000235:genetics / Q000502:physiology; D012621:Seasons; D048889:Weevils / Q000502:physiology
chemical_list: D018744:DNA, Plant