Genetic structures of Calophyllum inophyllum L., a tree employing sea-drift seed dispersal in the northern extreme of its distribution

So Hanaoka (1) , Ching-Te Chien (2) , Shun-Ying Chen (2) , Atsushi Watanabe (3) , Suzuki Setsuko (1) , Kazutaka Kato (1)

1 FFPRI - Forestry and Forest Products Research Institute
2 Taiwan Forestry Research Institute,
3 Faculty of Agriculture, Kyushu University

• Context Little is known about the potential of gene flow and resulting genetic structures of trees employing sea-drifting seed dispersal in island populations. • Aims Current genetic structure and the magnitude of histor-ical gene flow were estimated in island populations of Calophyllum inophyllum L., a typical plant employing sea-drifting seed dispersal. • Methods Samples were collected from the northern extreme of the species' distribution (Taiwan and the Sakishima, Daito, and Ogasawara Islands, Japan) and genotyped using 15 EST-SSR markers. Genetic differentiation (F ST and AMOVA), genetic structure (STRUCTRE analysis), and historical gene flow (assignment testing) were determined. • Results Frequent gene flow within and rare gene flow among island groups was determined using assignment testing. Clear genetic structures were also detected using the STRUCTURE analysis, which demonstrated differentia-tion between dominant clusters among geographically con-structed island groups. • Conclusions The potential for gene flow via sea-drifting seed dispersal was high, and this was possible even among small islands. However, the extent and frequency of gene flow were not great enough to prevent genetic differentiation in a range of over a few hundred kilometers.

Domaines: Sciences du Vivant [q-bio]

So Hanaoka, Ching-Te Chien, Shun-Ying Chen, Atsushi Watanabe, Suzuki Setsuko, et al.. Genetic structures of Calophyllum inophyllum L., a tree employing sea-drift seed dispersal in the northern extreme of its distribution. Annals of Forest Science, 2014, 71 (5), pp.575 - 584. ⟨10.1007/s13595-014-0365-5⟩. ⟨hal-01102592⟩