水肥(N)双因素下的小麦产量及水分利用率

WHEAT YIELD AND WATER-USE EFFICIENCY AS INFLUENCED BY DIFFERENT COMBINATIONS OF IRRIGATION WATER AND NITROGEN FERTILIZER

通过对6个水分等级和5个N肥等级的相互搭配研究,结果表明,灌溉水平105mm时,对小麦产量抑制较为明显;而当施N量<112.5kg/hm2时,N素成为增加小麦蒸散耗水和小麦产量的限制因素。但灌溉水平不同,小麦产量随施N量的增加而变化的趋势亦不同。当灌溉水平为475mm时,它们之间关系为典型抛物线。然而,小麦的水分利用率则随灌溉水量的增加而降低。只有当灌溉水平较低时,随着施N量增加,水分利用率有上升的趋势。

One field experiment was carried out in the Fengqiu Experimental Station. It consisted of six levels of irrigation water and five levels of nitrogen fertilizer. The results showed that water greatly limited the formation of wheat yield when the irrigation water was below 105mm, while N fertilizer became the major factor limiting wheat yield and evapotranspiration when the application rate was less than 112.5kg/hm2. The trend of yield increasing with N application rate changed with irrigation water, and a typical parabola was observed when the irrigation rate was 475mm. Water-use efficiency decreased with increase in irrigation water, however, a positive relationship between N application rate and water-use efficiency could be obtained only when the irrigation water was at the low level.