【摘要】 研究了化学氮肥种类、用量及基追肥比例对温室韭菜硝酸盐含量影响,结果表明:硫酸铵可明显降低温室韭菜硝酸盐的积累,基本上能达到WHO/FAO允许的限量标准。施氮越多,温室韭菜硝酸盐含量越高。温室韭菜施氮肥要注意“攻头控尾,重基肥轻追肥”的施N技术模式,有利于后期控制韭菜硝酸盐的积累量。在以硫酸铵为氮肥的情况下,追肥后12d可以视作温室韭菜的安全采收期。更多还原

【Abstract】 Effects of nitrogen fertilizer varieties,rates and different ratios of base N fertilizer to additional N fertilizer on the nitrate content of Leek in greenhouse were studied.The results showed that the nitrate content of Leek was reduced under the ammonium sulphate,it can up to par of WHO/FAO.The nitrate content increased with the increasing of nitrogen.The strategy of nitrogen fertilization should be "more at the beginning and less at end,more as the base fertilizer and less as additional fertilizer",which was adverted to be propitious to reduce the nitrate content.12 day was the minimum safe harvest time after ammonium sulphate fertilization.更多还原