Huang, Pu , Schaal, Barbara .
Phylogeography of Asian wild rice, Oryza rufipogon: a genome-wide view.
Asian wild rice (Oryza rufipogon) which ranges widely across the eastern and southern part of Asia is widely recognized as the direct ancestor of the cultivated Asian rice (O.sativa). Studies of the geographical structure of O.rufipogon, based on chloroplast and low-copy nuclear markers, reveal a possible phylogeographic signal of subdivision in O.rufipogon populations. However, this signal of geographical differentiation is not consistently observed among different markers and studies. Additionally, theoretical studies point out that inadequate geographic sampling, or incomplete lineage sorting due to the small number of markers, could potentially bias the detection of a phylogeographic signal. To more precisely characterize the phylogeography of O.rufipogon populations, a genome-wide survey of unlinked markers, intensively sampled from across the entire distribution range is critical. In this study, we surveyed sequence variation at 42 genome-wide sequence tagged sites (STS) in 96 O.rufipogon accessions from throughout the native range of the species. Using Bayesian clustering, principal component analysis and AMOVA, we conclude that there are two genetically distinct O.rufipogon groups, Ruf-I and Ruf-II. The two groups exhibit a clinal variation generally from northeast to southwest. Different from some earlier studies, Ruf-I which is found mainly in China and Indochinese peninsula, showed genetic similarity with one major cultivated rice variety, O.satvia indica. Whereas Ruf-II, mainly from South Asia and Indochinese peninsula, is not found within any cultivated rice varieties. Additional analysis using diffusion approximation suggests potential historical gene flow from cultivated rice into the O.rufipogon populations.
Log in to add this item to your schedule
1 - Washington University, Department Of Biology, CAMPUS BOX 1137, 1 Brookings Drive, St. Louis, MO, 63130-4899, USA
sequence tagged site.
Presentation Type: Poster:Posters for Topics
Location: Khorassan Ballroom/Chase Park Plaza
Date: Monday, July 11th, 2011
Time: 5:30 PM