根外追肥,就是不通过土壤,把肥料直接喷洒在农作物叶片上的施肥方法.根外追肥,肥料利用率高,作业方便、省工、省肥,能及时满足农作物对养分的需要,增加干物质积累而促进高产.适宜叶片喷洒的肥料有:尿素、过磷酸钙、磷酸二氢钾、草木灰、钼肥、硼肥、锌肥等.1.尿素 其分子体积小,容易渗入叶细胞,并且扩散性能强,易被 Root top dressing, is not through the soil, the fertilizer sprayed directly on the crop leaves on the fertilization method. Root top dressing, fertilizer utilization, easy operation, labor, fertilizer, to timely meet the needs of crop nutrients, increase dry The accumulation of material and promote high yield.Appropriate for leaf spraying of fertilizers are: urea, superphosphate, potassium dihydrogen phosphate, ash, molybdenum fertilizer, boron fertilizer, zinc fertilizer, etc. 1. The molecular size of urea, easy to infiltrate into leaf cells, and Diffuse performance, easy to be