Rice genetic resources: history, conservation, investigative characterization and use in Japan

摘要: Rice has been grown in Japan for about 3000 years. Although both japonica and indica varieties have Japan, now rices are grown. Japanese rice breeding used an ecological approach. While emphasis the 1940's 1950's focussed on yield recent decades quality of major importance. Consumer preference name recognition high varieties, such as Koshihikari, resulted slow acceptance new varieties. germplasm was systematically collected throughout between 1962 1963. Subsequent acquisition collecting, other countries, 28,000 accessions being conserved National Genebank, based at institute Agrobiological Resources (NIAR). Research genetic diversity using a range techniques, example esterase isozymes, revealed clinal variation radiating from center around southwest China. Newly found genes traditional germplasm, non-elongating mesocotyl, routinely identified genome. Pioneering studies eco-genetic differentiation species genus Oryza much complex genepool which evolved. Pest disease resistance sources, particularly to blast, bacterial blight brown plant hopper, many countries incorporated into Cold tolerance booting stage Indonesian variety Silewah. In future characterisation interaction specialists molecular scientists, internationally, will be corner stones securing improvement next century.