一、白菜类蔬菜。包括大白菜、大青菜、小青菜、黑白菜、油菜等,食用器官是叶片,生产特点是都有很大的叶面积,蒸腾量大,但根系浅。因此,较高的土壤含水量和肥沃的土壤,保证全生育期供应充足的氮肥,是大白菜丰产的关键。后期磷、钾肥要充足,适时适量施用微量元素是必要的。大白菜以吨产品计算,对氮、磷、钾的吸收量为氮0.8—2.6千克、五氧化二磷0.8—1.2千克、氧化钾3.2—3.7千克,其吸收比例为1:0.5:1.7。对微量元素的要求,以铁为主,钙、锌、硼、锰次之,铜最少。叶面喷施 First, cabbage vegetables. Including cabbage, big greens, small greens, black cabbage, rape and so on, edible organs are leaves, the production is characterized by a large leaf area, large transpiration, but the roots shallow. Therefore, the higher soil moisture and fertile soil, to ensure adequate supply of nitrogen throughout the growth period, is the key to cabbage yield. Late phosphorus, potassium fertilizer should be adequate, timely and appropriate use of trace elements is necessary. Calculated on a ton of Chinese cabbage, the absorption of nitrogen, phosphorus and potassium is 0.8-2.6 kg of nitrogen, 0.8-1.2 kg of phosphorus pentoxide, and 3.2-3.7 kg of potassium oxide. The absorption ratio is 1: 0.5: 1.7. The requirements of trace elements, mainly iron, calcium, zinc, boron, followed by manganese, copper at least. Foliar spray