title: Gene flow and inbreeding depression inferred from fine-scale genetic structure in an endangered heterostylous perennial, Primula sieboldii.
abstract: We estimated the gene dispersal distance and the magnitude of inbreeding depression from the fine-scale genetic structure in the endangered heterostylous perennial Primula sieboldii. We indirectly estimated the neighbourhood size (Nb) and the standard deviation of gene dispersal distance (sigma(g)) from the detected genetic structure by using 10 microsatellite markers. We also estimated the fitness reduction in mating among neighbouring individuals caused by biparental inbreeding according to the genetic structure. We found clear fine-scale genetic structure (a significantly positive kinship coefficient within 42.3 m), and the indirect estimates of sigma(g) and Nb were 15.7 m and 50.9, respectively. These indirect estimates were similar to the direct estimates (18.4 m and 44.0). The slightly larger indirect estimate of Nb may reflect that inbreeding depression and genetic structure or rare long-distance dispersal that were overlooked in the direct estimate have elongated the long-term average of gene dispersal distance. P. sieboldii is also likely to suffer about 19% fitness reduction in progenies from mating among individuals 5 m apart. Our results suggest that biparental inbreeding and genetic structure can affect the range of gene dispersal and seed reproductive success in P. sieboldii.
authors.affiliation: Graduate School of Agricultural and Life Sciences, University of Tokyo, 1-1-1 Yayoi, Bunkyo, Tokyo 113-8657, Japan. isihama7@dolphin.c.u-tokyo.ac.jp
authors.forename: Fumiko
authors.initials: F
authors.lastname: Ishihama
authors.forename: Saneyoshi
authors.initials: S
authors.lastname: Ueno
authors.forename: Yoshihiko
authors.initials: Y
authors.lastname: Tsumura
authors.forename: Izumi
authors.initials: I
authors.lastname: Washitani
mesh_terms: D018744:DNA, Plant / Q000235:genetics*; D005828:Genetics, Population; D007178:Inbreeding; D007564:Japan; D018895:Microsatellite Repeats; D008957:Models, Genetic; D018515:Plant Leaves / Q000235:genetics; D011156:Population Density; D031825:Primula / Q000235:genetics*; D012098:Reproduction; D012639:Seeds / Q000235:genetics
chemical_list: D018744:DNA, Plant