土壤肥力和施氮量对小麦氮素吸收运转及籽粒产量和蛋白质含量的影响

在不同土壤肥力条件下，研究了施氮量对小麦氮素吸收、转化及籽粒产量和蛋白质含量的影响。结果表明，增施氮肥可以提高小麦各生育阶段的吸氮强度，尤以生育后期提高的幅度为大认为是增施氮肥提高小麦籽粒产量和蛋白质含量的基础，增施氮肥虽提高了小麦植株的吸氮强度。吸氮量增加，但开花后营养器官氮素向籽粒中的转移率降低，增施氮肥不仅促进了小麦植株对肥料氮的吸收，而且也促进了对土壤氮的吸收，并讨论了在高、低土壤肥力条件下氮肥合理运筹的问题。

Effects of soil fertility and nitrogen application rate on nitrogen absorption and translocation, grain yield, and grain protein content of wheat

The results of this study showed that nitrogen application improved the nitrogen uptake by wheat, especially during its late growth stage. Although a higher nitrogen application rate could increase the amount of absorbed nitrogen, an excess of nitrogen would remain in vegetative organs at the stage after flowering, owing to the low translocation rate of nitrogen from these organs to the grain, and hence, the nitrogen use efficiency and nitrogen harvest index were decreased. Compared with that on high fertility soil, the ratio of nitrogen absorbed from fertilizer to total absorbed nitrogen was higher when the wheat was grown on low fertility soil. On high fertility soil, wheat plant absorbed more nitrogen from top-dressed fertilizer than from basis fertilizer, and top-dressed fertilizer contributed more nitrogen to the grain . It was reversed on low fertility soil.