Abstract:

Recently, although the unit grain yield and total grain output in China have been increasing, the grain yield increasing rate under unit fertilizer is dropping sharply. The level of unit production is far below that in demonstration cropland. In order to explore the scientific measures and methods for improving level of unit yield, and to apply research findings of new fertilization theory, this paper analyzes the rule for increasing grain unit  yield the influencing factors since 1978. The result indicates that the grain unit yield is increased step by step, which promotes crop varietys update  through increasing the applying quantity of fertilizer step by step. Fertilizer tolerance and fertilizer utilization efficiency are the basic characteristics of crop variety. The highest yield is an expressing form of crop variety characteristics under suitable fertilization. To realize the sustainable increasing of yield, key measures are to adjust the applying ratio between nitrogen and phosphorus, to increase the phosphorus applying quantity, and to increase crop planting density at the same time. From the long run, we should use new fertilizer applying technology and  balance fertilization in soils with different fertilizer levels,which are the orientation for us to realize sustainables grain yield increasing.

Key words: grain yield, stepwise increase, medium and low yielding cropland, fertilizer applying technology

摘要：

近年来, 我国粮食单产和总产虽然一直在增加，但单位肥料的粮食增产率却在急剧下降，农业生产中的单产水平远低于示范产量。为了探索提高单产水平的科学措施和方法，应用新的施肥理论研究结果，对我国1978年以来粮食单产的增加规律及其影响因素进行了研究分析，结果表明，我国粮食单产呈阶梯式阶段性增加规律，它是施肥量阶段增加推动下作物品种更新的结果。耐肥性和肥料利用效率是作物品种的基本特性，作物最高产量是作物品种特性在合理施肥条件下的表现形式。而要实现品种高产潜力水平下的持续增加，应采取的关键措施就是调整氮磷施用比例，增加肥料施用中磷肥的施用量，同时提高农作物种植密度。从长远来看，应把依靠新的施肥技术在不同土壤肥力水平上进行平衡施肥育种，作为我国实现持续增产的主攻方向。

关键词: 粮食产量；阶梯式增加；中低产田;施肥技术