尿素是酰胺态氮肥,含氮46％,是固体氮肥中含氮量最高的氮肥。酰胺态氮,作物根系不能吸收利用,只有当其以铵态氮形式存在时,作物根系才可吸收利用,同时尿素中还含有毒物质缩二脲。鉴于上述特点,施用尿素应掌握如下方法:一、尿素作种肥要远离种子:由于尿素养分浓,又含有缩二脲,一般不宜作种肥, Urea is an amide nitrogen fertilizer, nitrogen 46%, is the highest nitrogen content in solid nitrogen fertilizer nitrogen. Amide nitrogen, crop roots can not be absorbed, only when it is in the form of ammonium nitrogen, the crop roots can be absorbed and utilized, while urea also contains toxic biuret. In view of the above characteristics, the application of urea should have the following methods: First, urea as seed fertilizer to stay away from the seeds: Due to urea nutrient concentration, but also contains biuret, generally not suitable for seed fertilizer,