WorkshopsW3-5 Genome diversity among inter- and intra-species of rice and its relationship to functional differentiation of the genome

The genus Oryza consists of nine genomes currently including 23 species and these species have wide habitat all over the world of tropical and subtropical area. More than 1,700 accessions of 23 wild species collected in the NIG show various characteristics in their phenotypes. These are excellent resources for examining genome differentiation and evolution. We are pursuing studies to analyze relationships between primary structural variations accumulated in the genome at species or subspecies level and functional divergence caused by such variations. One approach aiming to resolve the relations is identification and characterization of factors that induce reproductive barriers between species. Some special characters on reproductive barriers have been emerged from the analysis of rice crosses between subspecies. Another approach would be association analysis or e-QTL analysis using natural or structured population. These analyses are expected to correlate genotypes with phetotypes directly. Although the second approach is in the preliminary step, it would be an efficient way to resolve these problems by applying resequencing methods of whole genome and/or transcripts.