水稻生长期间需要氮肥,不久前日本专家培育出一种可以自己供给氮肥的水稻。在这种水稻的根部成功地繁殖了可以从空气中固氮的根瘤菌。通常,根瘤菌都是在豆科植物根上进行繁殖,营共生生活,从植物体中吸取二氧化碳,而本身则向植物体提供含氮化合物。日本专家对世界各地区5000多个水稻品种进行了研究, Nitrogen fertilizer is needed during rice growth. Not long ago, Japanese experts bred rice that could supply nitrogen fertilizer by itself. Rhizobium, which fixes nitrogen from the air, is successfully propagated at the root of this rice. Rhizobia usually breed on the roots of legumes, live in symbiosis, extract carbon dioxide from plants and provide nitrogenous compounds to plants. Japanese experts conducted a study of over 5,000 rice varieties in various regions of the world,