title: Influence of long-distance seed dispersal on the genetic diversity of seed rain in fragmented Pinus densiflora populations relative to pollen-mediated gene flow.
abstract: Long-distance dispersal (LDD) of seeds has a critical impact on species survival in patchy landscapes. However, relative to pollen dispersal, empirical data on how seed LDD affects genetic diversity in fragmented populations have been poorly reported. Thus, we attempted to indirectly evaluate the influence of seed LDD by estimating maternal and paternal inbreeding in the seed rain of fragmented 8 Pinus densiflora populations. In total, the sample size was 458 seeds and 306 adult trees. Inbreeding was estimated by common parentage analysis to evaluate gene flow within populations and by sibship reconstruction analysis to estimate gene flow within and among populations. In the parentage analysis, the observed probability that sampled seeds had the same parents within populations was significantly larger than the expected probability in many populations. This result suggested that gene dispersal was limited to within populations. In the sibship reconstruction, many donors both within and among populations appeared to contribute to sampled seeds. Significant differences in sibling ratios were not detected between paternity and maternity. These results suggested that seed-mediated gene flow and pollen-mediated gene flow from outside population contributed some extent to high genetic diversity of the seed rain (H E > 0.854). We emphasize that pine seeds may have excellent potential for gene exchange within and among populations.
authors.affiliation: Fukushima Prefectural Forestry Research Centre, 1 Nishijimasaka, Narita, Asaka-machi, Koriyama 963-0112, Japan. ozawa_hajime_01@pref.fukushima.lg.jp
authors.forename: Hajime
authors.initials: H
authors.lastname: Ozawa
authors.forename: Atsushi
authors.initials: A
authors.lastname: Watanabe
authors.forename: Kentaro
authors.initials: K
authors.lastname: Uchiyama
authors.forename: Yoko
authors.initials: Y
authors.lastname: Saito
authors.forename: Yuji
authors.initials: Y
authors.lastname: Ide
mesh_terms: D032485:Cryptomeria / Q000235:genetics; D051456:Gene Flow / Q000502:physiology*; D005787:Gene Frequency; D014644:Genetic Variation / Q000502:physiology*; D005843:Geography; D007564:Japan; D018895:Microsatellite Repeats / Q000235:genetics; D028223:Pinus / Q000196:embryology / Q000235:genetics*; D011058:Pollen / Q000235:genetics* / Q000502:physiology; D011891:Rain; D058614:Seed Dispersal / Q000235:genetics / Q000502:physiology*; D012639:Seeds / Q000235:genetics / Q000502:physiology; D014919:Wind
keywords: maternal inbreeding; parentage analysis; paternal inbreeding; seed rain; sibship reconstruction