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低产型小麦吸氮进程慢,累积数量少,且有一个停顿时期;高产型初期吸氮少,返青后迅速加快,累积数量多,后期平稳增长。吸氮进程支配干物质的积累过程和产量构成。支配氮吸收进程的土壤因素主要是全氮含量、碳氮比值、易分解性有机质的含量。施肥可以促进土壤氮的供应过程,但增产幅度受土壤供氮量所制约。小麦氮吸收和磷吸收之间的关系表现为:低产麦田的磷吸收由氮肥所制约;高产麦田的氮吸收由磷肥所制约。
Low-yielding wheat had slow nitrogen uptake and a small accumulation, and had a standstill period. In the early stage of high-yielding, nitrogen uptake was low, rapidly after returning to green, accumulating in large quantity and steadily increasing in later period. Nitrogen uptake process dominates dry matter accumulation and yield composition. Soil factors governing the process of nitrogen uptake are mainly total nitrogen, carbon to nitrogen ratio and readily degradable organic matter. Fertilization can promote the process of soil nitrogen supply, but the rate of increase is limited by soil nitrogen supply. The relationship between nitrogen uptake and phosphorus uptake by wheat is as follows: the phosphorus uptake in low yielding wheat fields is controlled by nitrogen fertilizers; and the nitrogen uptake by high yielding wheat fields is controlled by phosphate fertilizers.