title: Genetic diversity and genetic relationships ofjaponicarice varieties in Northeast Asia based on SSR markers.
abstract: Genetic diversity and the relationship among ninejaponicarice groups consisting of 288 landraces and varieties in different geographical origins of Northeast Asia (China, Japan, Korea, Democratic People's Republic of Korea) and the Russian Far East district of the Russian Federation were evaluated with 154 simple sequence repeat (SSR) markers. A total of 823 alleles were detected. The observed allele numbers (Na) per locus, Nei's gene diversity (He) and the polymorphism information content (PIC) ranged from 2 to 9, 0.061 to 0.869 and 0.060 to 0.856, with an average of 5.344, 0.624 and 0.586, respectively. Five SSR loci, RM1350, RM1369, RM257, RM336 and RM1374, provided the highest PIC values and are potential for exploring the genetic diversity of rice cultivars in Northeast Asia. Molecular variance analysis showed that a significant difference existed both among groups (91.6%) and within each group (8.4%). The low genetic variation within each group indicated that the gene pool is narrow and alien genetic variation should be introduced into the rice breeding program in Northeast Asia. Based on the He and PIC values, the nine groups were ranked in a descending order: Heilongjiang landraces, Jilin landraces, Japanese improved varieties, Heilongjiang improved varieties, Russian Far East district of the Russian Federation improved varieties, Liaoning improved varieties, Jilin improved varieties, Korean improved varieties and Democratic People's Republic of Korea improved varieties. The nine groups were further divided into three subgroups and the 288 varieties into five clusters. This study provided information for parent selection in order to broaden the gene pool of thejaponicarice germplasm in Northeast Asia.
authors.affiliation: State Key Laboratory of Tree Genetics and Breeding, Northeast Forestry University , Heilongjiang , P.R. China ; The Rice Research Institute, Northeast Agricultural University , Heilongjiang , P.R. China.
authors.forename: Jingguo
authors.initials: J
authors.lastname: Wang
authors.affiliation: State Key Laboratory of Tree Genetics and Breeding, Northeast Forestry University , Heilongjiang , P.R. China.
authors.forename: Tingbo
authors.initials: T
authors.lastname: Jiang
authors.affiliation: The Rice Research Institute, Northeast Agricultural University , Heilongjiang , P.R. China.
authors.forename: Detang
authors.initials: D
authors.lastname: Zou
authors.affiliation: The Rice Research Institute, Northeast Agricultural University , Heilongjiang , P.R. China.
authors.forename: Hongwei
authors.initials: H
authors.lastname: Zhao
authors.affiliation: Heilongjiang Province Economic Research Institute of State Farm , Heilongjiang , P.R. China.
authors.forename: Qiang
authors.initials: Q
authors.lastname: Li
authors.affiliation: The Rice Research Institute, Northeast Agricultural University , Heilongjiang , P.R. China.
authors.forename: Hualong
authors.initials: H
authors.lastname: Liu
authors.affiliation: Heilongjiang Agriculture Academic Sciences, Daqing Branch , Heilongjiang , P.R. China.
authors.forename: Changjun
authors.initials: C
authors.lastname: Zhou
keywords: Northeast Asia; genetic diversity; japonica rice; simple sequence repeat (SSR)