旱田追肥主要对象是玉米等中耕作物，玉米居次根系作物，吸肥量大，目前又多种植高产晚熟品种，需肥量大，单靠上镶自然肥力和施农家肥，不能满足生产发育的需要，必须适量施用化肥，以补偿上壤肥力不足，增加玉米产量．玉米所需的营养物质以Ｎ为最多，Ｋ次之，Ｐ最少．所有的 The main target of topdressing in dry land is maize and other mid-tillage crops. Maize is the second most important root crop and has a large amount of fat absorption. At present, more high-yielding late-maturing varieties are planted, with large amount of fertilizer needed. Natural fertility alone and top- The need, the amount of fertilizer must be applied to compensate for lack of soil fertility, increase corn production. N nutrients needed for the most N, K times, P least. all