【摘要】 采用盆载和田间小区试验研究了小麦和玉米叶面10g／L尿素、10g／LKH2PO4和5．4g／LKCl及其配合施用的一些生理效应。叶面施用尿素，尤其是N，P和K的配合施用可显著延缓两种作物在拔节后其根系活力的下降。叶面追肥增强了两种作物功能叶的生理活性，在N，K或P＋K三者之间，尿素的效果较佳。三者的配合施用是最大限度延长叶片寿命的措施。作物后期喷尿素＋KH2PO4能显著增加小麦和玉米的籽粒产量。叶面施用N、P、K肥不仅提高了作物体内N，P，K的含量，而且改变了它们在不同部位的分配，促进N素向籽粒运转，10g／L尿素＋10g／LKH2PO4处理可分别提高小麦和玉米籽粒的蛋白质含量的绝对值22g／kg和4．9g／kg。更多还原

【Abstract】 Pot sand cultUre of summer corn with Hoagland solution and soil culture of winter wheat with application of routine dosage of 0.15g N, 0.05 g P and 0.10 g K Per kg of soil were carried out in greenhouse of Nanjing Agricultural University.Leaves of corn and wheat were wiped or dipped with 15N-labelled 10 g/L urea、10 g/L KH2PO4、5.4 g/L KCl and their combinations from jointing stage of both crops to the silking of corn or heading stage of wheat. The root activities of both crops were rapidly declined after jointing stage, but thes decline apparently delayed as foliar application of urea,especially foliar feeding with N, P and K cooperated. Foliar feeding with macro-element fertilizers enhanced physiological activity of function leaves. Among the three elements for raising physiological indexes of function leaves urea-N was most efficient except small variation of total activity of RUBPase. Foliar application of N, P and K cooperated would be the measure for prolonging the life of leaves to the most limit. Statistical results showed that compated to foliar spray of water, urea+KCl and urea+KH2PO4 increased the yield of wheat significantly, while for corn only urea+KH2PO4 increased its ear and grain yields. Foliar application not only increased N, P and K content of plants, but also changed their distribution in organs and stimulated translocation of N to grain. Absolute protein contents of wheat and corn grains increased by 22 g/kg and 4.9g/kg, respectively, due to foliar feeding during the middle and latter growing periods.更多还原