中文摘要：

小麦与豆科绿肥轮作和合理施用氮肥对黄土高原旱地缺素地区具有特别重要意义。本试验以夏休闲为对照,比较了小麦与绿豆、大豆、秋豆轮作和氮肥水平（0、108、1351、62 kg/hm2）对小麦产量和籽粒养分的影响。结果表明,小麦与豆科绿肥轮作,在黄土高原旱地受水分限制影响,小麦产量降低9.7%~26.6%;同时,与休闲处理相较,小麦籽粒养分携出量显著降低或表现出降低的趋势,其中,与绿豆轮作,小麦籽粒养分携出量降低最多,为10.5%~29.3%,大豆次之,为3.1%~12.8%,与当地大豆品种秋豆轮作,小麦籽粒养分携出量降低最少,为0.98%~11.7%。然而,小麦籽粒营养元素锌、磷、钾、钙、镁的含量与休闲处理相比,分别增加22.0%、18.5%、8.8%、7.9%、7.8%。小麦与绿肥轮作后,108 kg N/hm2（当地常规施氮量的80%）获得了较高小麦生物量和产量。同时,随施氮量的增加,小麦籽粒氮、硫、钙、铁、铜、锌的含量和养分携出量均表现出增加趋势;小麦籽粒含磷量和养分携出量有下降趋势;小麦籽粒锰含量呈现降低趋势但养分携出量增加;钾、镁的含量和养分携出量随施氮量无显著变化。

英文摘要：

It is of profound importance to study effects of rotation with legumes and N input levels on yield and grains nutrient contents of wheat in dryland of the Loess Plateau,where people are in trouble of malnutrition and soils are condemned to be deficient in available nutritional elements.A field experiment was carried out to study the effects of rotation with legumes on wheat yield and nutrient contents of wheat grains with four rotation types（fallow-wheat,mung bean-wheat,soybean-wheat,and qiubean（local bean）-wheat） at four N input levels of 0,108,135 and 162 kg/hm2 on dryland of the Loess Plateau.Obtained results showed that wheat yield was significantly decreased by 9.7%～26.6% due to water deficiency after rotation with legumes.By comparison with fallow treatment,the amount of nutrients-absorbed of wheat grains decreased significantly or slightly.Specifically,the decreased amount of nutrients-absorbed of wheat grains was from10.5% to 29.3% after rotation with mungbean,which decreased the most of three rotation types,and the second was rotation with soybean,the decreased amount of nutrients-absorbed was from 3.1% to 12.8%,whereas after rotation with qiubean（local bean）,the decrease was merely from 0.98% to 11.7%,which was the least among three rotation types.However,by rotation with legumes,the average contents of Zn,P,K,Ca and Mg of wheat grains were increased by 22.0%,18.5%,8.8%,7.9% and 7.8%,respectively.Among three N input levels,108 kg N/hm2（80% of local routine N rates） showed higher wheat yields.With the increasing of N input,the contents and the amount of absorbed N,S,Ca,Fe,Cu and Zn of wheat grains tended to be increased,on the contrary,P contents and P-absorbed amount were decreased,and Mn contents decreased but Mn-absorbed amount was increased,whereas K and Mg were not significantly influenced.