在水稻栽培上,为了获得经济的稻谷产量,应该有效地使用氮素肥料。增加氮素肥效的方法之一,是分期分批施用,既可减少氮素损失至最低限度,又为水稻植株的正常生长和营养不断提供氮素肥料。按照水稻植株不同生长阶段的需要追施氮肥的想法,在生长水稻的温带国家如日本和热带国家如印度、菲律宾,都在进行研究。在热带所进行试验是用高秆易倒伏的品种。对易倒伏的品种,分期分批施用氮肥是 In rice cultivation, nitrogen fertilizers should be used effectively in order to obtain economic rice yields. One of the ways to increase nitrogen fertilizer efficiency is to apply in batches and batches, which can not only reduce nitrogen loss to a minimum, but also provide nitrogenous fertilizer for the normal growth and nutrition of rice plants. The idea of ​​topdressing nitrogen at different growth stages of rice plants is under investigation in temperate countries that grow rice such as Japan and tropical countries such as India and the Philippines. Experiments carried out in the tropics are high stalk prone varieties. For lodging varieties, application of nitrogen fertilizer in batches is