title: Evaluation of genetic variation among wild rice populations in Cambodia.
abstract: A total of 448 samples in five natural populations of wild rice (Oryza rufipogon) were collected in Cambodia. They were examined using 12 SSR and two chloroplast markers to evaluate the degree of variation among populations and the genetic structure within populations. In the two annual populations, the number of plants with homozygous alleles at all 12 SSR loci were high (66.3% and 79.5%), suggesting that these plants propagate mainly through self-pollination. In the three perennial populations, no individuals had all homozygous genotypes, but redundant genotypes resulted from clonal propagation were observed. Percentages of the redundant genotypes were highly varied (3.6%, 29.2% and 86.0%). This may be due to the different stable levels of environmental conditions. As for chloroplast genome, most of the wild plants showed the same chloroplast types as most Indica-type cultivars have. However, plants with different chloroplast types were maintained, even in the same population. In tropical Asian countries, many wild rice populations were observed under similar ecological conditions examined in this study. Therefore, the present results concerning population structure will be important to further elucidate genetic features of wild rice, and will also give strong clues to utilize and conserve wild natural genetic resources.
authors.affiliation: Graduate School of Agricultural Science, Kobe University , 1-1 Rokkodai, Nada-ku, Kobe, Hyogo 657-8501 , Japan ; Cambodian Agricultural Research and Development Institute (CARDI) , Pratash Lang, Khan Dongkor, National Road No. 3, Phnom Penh , Cambodia.
authors.forename: Chhourn
authors.initials: C
authors.lastname: Orn
authors.affiliation: College of Bioresource Sciences, Nihon University , Kameino, Fujisawa, Kanagawa 252-8510 , Japan.
authors.forename: Rieko
authors.initials: R
authors.lastname: Shishido
authors.affiliation: Obihiro University of Agriculture and Veterinary Medicine , Inada, Obihiro, Hokkaido 080-8555 , Japan.
authors.forename: Masahiro
authors.initials: M
authors.lastname: Akimoto
authors.affiliation: Graduate School of Agricultural Science, Kobe University , 1-1 Rokkodai, Nada-ku, Kobe, Hyogo 657-8501 , Japan.
authors.forename: Ryo
authors.initials: R
authors.lastname: Ishikawa
authors.affiliation: Graduate School of Agricultural Science, Kobe University , 1-1 Rokkodai, Nada-ku, Kobe, Hyogo 657-8501 , Japan.
authors.forename: Than Myint
authors.initials: TM
authors.lastname: Htun
authors.affiliation: National Institute of Genetics , Mishima, Shizuoka 411-8540 , Japan.
authors.forename: Ken-Ichi
authors.initials: K
authors.lastname: Nonomura
authors.affiliation: Hakubi Center for Advanced Research/Graduate School of Agriculture, Kyoto University , Kitashirakawa-Oiwakecho, Sakyo, Kyoto 606-8502 , Japan.
authors.forename: Yohei
authors.initials: Y
authors.lastname: Koide
authors.affiliation: Royal University of Agriculture (RUA) , Khan Dongkor, Phnom Penh , Cambodia.
authors.forename: Men
authors.initials: M
authors.lastname: Sarom
authors.affiliation: Cambodian Agricultural Research and Development Institute (CARDI) , Pratash Lang, Khan Dongkor, National Road No. 3, Phnom Penh , Cambodia.
authors.forename: Seng
authors.initials: S
authors.lastname: Vang
authors.affiliation: Cambodian Agricultural Research and Development Institute (CARDI) , Pratash Lang, Khan Dongkor, National Road No. 3, Phnom Penh , Cambodia.
authors.forename: Sakhan
authors.initials: S
authors.lastname: Sophany
authors.affiliation: Cambodian Agricultural Research and Development Institute (CARDI) , Pratash Lang, Khan Dongkor, National Road No. 3, Phnom Penh , Cambodia.
authors.forename: Ouk
authors.initials: O
authors.lastname: Makara
authors.affiliation: Graduate School of Agricultural Science, Kobe University , 1-1 Rokkodai, Nada-ku, Kobe, Hyogo 657-8501 , Japan.
authors.forename: Takashige
authors.initials: T
authors.lastname: Ishii
keywords: Cambodia; Oryza rufipogon Griff.; annual; genetic variation; perennial; wild rice population