Advances in rice chromosomes research

Rice chromosome research was initiated around 1910 and has been progressing ever since. Twelve pairs of chromosomes (2n = 24) and a 440 Mb genome, the smallest genome among all main cereal crops, have been identified. According to the recent rice chromosome researches, all chromosomes were well identified over the disadvantages of small chromosome size and quantitative rice chromosomal maps have been developed using chromosome image analysis system (CHIAS). Moreover, agriculturally important genes have been detected using new direct DNA visualization methods with fluorescence in situ hybridization (FISH). This review describes the recent progress in molecular and digital cytogenetics using visualization from a historical perspective, highlighting the future prospects in rice chromosome science. (Communicated by Eishiro SHIKATA, M.J.A.)