The effect of tillage system and residue management on grain yield and nitrogen use efficiency in winter wheat in a cool Atlantic climate

The effects of soil tillage and straw management systems on the grain yield and nitrogen use efficiency of winter wheat (Triticum aestivum L. em. Thell.) were evaluated in a cool Atlantic climate, in central Ireland between 2009 and 2011. Two tillage systems, conventional tillage (CT) and reduced tillage (RT) each with and without incorporation of the straw of the preceding crop, were compared at five levels of fertiliser N (0, 140, 180, 220 and 260 kg N ha⁻¹).CT had a significantly higher mean grain yield over the three years but the effect of tillage varied between years. Yields did not differ in 2009 (Year 1), while CT produced significantly higher grain yields in 2010 (Year 2), while RT produced the highest yields in 2011 (Year 3). Straw incorporation had no significant effect in any year.Nitrogen application significantly increased the grain yields of all establishment treatment combinations. Nitrogen use efficiency (NUE) ranged from 14.6 to 62.4 kg grain (85% DM) kg N ha⁻¹ and decreased as N fertiliser rate was increased.The CT system had a significantly higher mean NUE over the three years but the effect of tillage varied with years. While there was no tillage effect in years 1 and 3, CT had a significantly higher NUE than RT in year 2. Straw management system had minimal effect on NUE in any year.The effect of tillage and N rate on soil mineral N content also varied between years. While there was no tillage effect in years 1 and 3, RT had significantly larger soil N contents than CT in the spring before N application, and post-harvest in year 2. N application rates had no effect on soil N in year 1, increased residual N content in year 2 and had an inconsistent effect in year 3. Straw management had no significant effect on soil mineral N content.These results indicate that RT establishment systems can be used to produce similar winter wheat yields to CT systems in a cool Atlantic climate, providing weather conditions at establishment are favourable. The response to nitrogen is similar with both tillage systems where the crop is successfully established. Straw management system has very little effect on crop performance or nitrogen uptake.     

水氮配置对华北冬小麦-夏玉米种植体系氮素利用及土壤硝态氮残留的影响

针对华北平原冬小麦-夏玉米轮作体系存在过量的水、氮投入问题,本研究于2008 -2010年在河北吴桥设置了传统水氮、传统水氮调整、节水减氮和最少水氮4个水氮模式,以分析减少水氮投入后冬小麦-夏玉米体系的产量、氮素利用和土壤氮残留情况.结果表明:与传统水氮相比,节水减氮模式的氮肥投入量下降55％,水分投入量下降36.6％...     

不同类型高产小麦氮素积累及施氮对策探讨

本文通过对３个不同类型的高产小麦品种的植株定期取样分析测定,讨论了高产小麦全生育期中植株茎秆和叶片氮素含量,积累强度及积累进程的差异及变化,进而探讨了超高产小麦的合理施氮对策。     

Effect of Different Preceding Crops and Crop Rotations on Yield of Winter Oil-seed Rape (Brassica napus L.)

To determine the effect of different preceding crops and crop rotations on the grain yield of oil-seed rape, a long-term rotation experiment was conducted at the Hohenschulen experimental station in Kiel, NW Germany. Additional factors included the nitrogen fertilization and the fungicide application. The results reported herein are based upon the harvest years 1988 to 1993. Averaged over the different rotations and husbandry treatments, the grain yields in the 6 experimental years varied between 2.71 t ha^?1 and 3.99 t ha^?1. In contrast, the effect of the different husbandry treatments was smaller and non significant. Averaged over 6 years, only the fungicide application caused small yield increase of 0.2 t ha^?1. The highest grain yields of 3.77 t ha^?1 or 3.65 t ha^?1 occurred when oil-seed rape was directly following peas. Low yields between 3.15 tha^?1 and 3.33 tha^?1 were obtained when oil-seed rape was grown after oilseed rape. The lowest grain yield of 3.13 t ha^?1 was produced with oil-seed rape grown in monoculture only. In rotations with oil-seed rape following a preceding cereal crop (wheat or barley), the grain yields averaged between 3.22 tha^?1 in a two course rotation and up to 3.44 tha^?1 in a four course rotation. In general, the yields of oil-seed rape increase with the length of the rotation and the length of the break between two oilseed rape crops. The yield component number of seeds per m² was affected by the previous cropping accordingly, whereas the thousand seed weight did not respond to the cropping history. Based upon disease assessments in the first years of this experiment, we argue that an increase in the incidence of fungal diseases has considerably contributed to the yield decrease of oil-seed rape in short rotations.     

土壤肥力和灌水组合对小麦植株-土壤系统氮素平衡的影响

采用15N示踪技术,在池栽群体条件下,研究了三种土壤肥力和两种灌水量组合对冬小麦生产系统氮素平衡的影响,结果表明：（1）不同处理氮肥的当季吸收利用率变化在39.08%~53.08%,土壤残留率在21.80%~33.59%之间,损失率变化幅度为18.81%~34.62%,植株吸收积累氮素中的29.88%~47.55%来自肥料;证明,采用不同土壤肥力和灌水量组合来调控小麦生产系统的氮素平衡具有较大的空间。（2）随土壤肥力的提高,植株吸收的总氮和土壤氮量显著增加,但营养体滞留量增加,向子粒的分配比例减少;而对肥料氮的吸收量则表现为中肥>高肥>低肥;氮肥损失率表现为低肥>高肥>中肥,残留率无明显变化,说明土壤肥力达到本实验的中等水平后再继续提高,会给肥料氮的吸收利用带来不利影响,但可有效降低对肥料氮的依赖。（3）增加灌水量在不同土壤肥力条件下均可促进对总氮的吸收量,但对土壤氮吸收的促进作用远高于肥料氮,同时也提高了肥料氮的损失率、降低了土壤残留率和向子粒的分配率。（4）提高土壤肥力和增加灌水量均可提高小麦的经济产量、生物产量和土壤A值,降低收获指数;子粒蛋白质含量随肥力的提高而增加,随灌水的增加而下降。     

秸秆还田条件下适量施氮对冬小麦氮素利用及产量的影响

2011—2012和2012—2013年生长季,通过田间定位试验,研究了秸秆还田配施氮肥对冬小麦干物质积累、氮效率、土壤硝态氮积累及产量的影响。与单施氮肥(对照)相比,秸秆还田显著提高冬小麦全生育期干物质积累总量,降低开花前干物质积累量及其占全生育期比例;秸秆还田配施纯氮225 kg hm–2处理的氮肥偏生产力、氮素利用效率、氮素收获指数分别提高7.5%、6.4%和5.2%。秸秆还田显著降低了不同土层硝态氮积累量,尤其是0~30 cm和30~60 cm土层。秸秆还田配施纯氮225 kg hm–2的产量最高,且显著高于其他处理,增产幅度最大,因此可作为当地秸秆还田模式下适宜推荐的施氮量。     

氮肥运筹对限水灌溉冬小麦产量及氮素利用的影响

华北地区是中国小麦的主产区,也是缺水最为严重的地区之一,农业用水用肥过量正威胁着这个地区地下水资源的数量和质量。为此,笔者于中国农业大学吴桥实验站研究了不同氮肥措施对冬小麦产量、氮素和水分利用、以及土壤硝态氮残留的影响。实验在春浇一水和春浇二水两种水分限制条件下,分别设7个氮肥处理,即在4个等级氮肥用量（分别为0、157.5kg/hm2、226.5kg/hm2、295.5kg/hm2,不包括有机肥中所含氮量）下,分设两种施肥方式（全部基施和基施+追施）。结果表明,施氮量和施氮方式相同时春浇二水冬小麦的产量高于春浇一水,二水穗粒数较一水高,千粒重则低于一水,一水耗水量较少,水分利用效率明显高于二水;同一水分下不同施肥量及施肥方式对产量的影响差异不显著,同一施肥方式下在157.5-295.5kg/hm2范围内,施肥量越大,氮素生理效率和氮肥生产力越低,施氮157.5kg/hm2时,氮收获指数均处在最高或较高水平;土壤硝态氮残留量与施氮量呈显著正相关,成熟期一水条件下土壤中硝态氮主要集中在上层(0~80cm),二水条件下则主要分布在中下层。综合研究表明,在春浇一水条件下,施氮水平在157.5kg/hm2,且全部基施,能够获得与多量施肥相当的产量,且可提高氮肥和水分利用效率,减少硝态氮的淋洗和残留,提高劳动生产率,在干旱缺水地区是比较合理的栽培方式     

基于养分平衡和土壤测试的冬小麦氮素优化管理方法研究

以养分平衡和土壤测试为基础,把氮素供应与作物氮肥特性结合起来,通过田间试验研究冬小麦分期优化供氮量。结果表明：冬小麦播种前0~30cm土壤Nmin大于30 kg/hm2时,不施基肥（氮）,足以满足冬小麦从播种到返青期对氮素的需求;返青期保证供氮量90 kg/hm2 (0~60 cm土壤Nmin+肥料氮),可以满足冬小麦从返青期到拔节期对氮素的需求;拔节期保证供氮量100 kg/hm2 (0~90 cm土壤Nmin+肥料氮),可以满足冬小麦从拔节期到收获期对氮素的需求,最终达到目标产量。上述返青期90 kg/     

不同施氮量对冬小麦产量、效益及土壤理化性状的影响

为探明豫北地区高肥力地块不同施氮量对冬小麦产量、经济效益及土壤理化性状的影响,在安阳市北关区壤质潮土上开展了冬小麦不同施氮量试验,设常规施磷钾肥（W1,CK）、常规施肥减施氮肥30%（W2）、常规施肥减施氮肥15%（W3）、常规施肥减施氮肥5%（W4）、常规施肥（W5）和常规施肥增施氮肥5%（W6）6个处理。结果表明,随着氮肥施用量的减少冬小麦主茎叶龄、次生根数、茎蘖数、株高及穗长等农艺性状呈下降趋势,以W6处理最佳。冬小麦产量随着施氮量的增加呈上升趋势,W4、W5、W6处理与W1处理相比增幅分别达48.7%、48.9%、49.1%,W4、W5、W6处理间差异不显著;但与W2、W3处理间差异达到显著水平。不同施氮量处理经济效益较W1处理均有不同程度增加,W4较W1处理净增效益5 869.80元/hm ²,较W5处理净增效益24.45元/hm ²。不同施氮量处理对土壤有机质、全氮、有效磷、速效钾、缓效钾含量和土壤容重有显著影响,但对pH影响不显著。土壤全氮含量随施氮量的增加呈上升趋势;W4处理土壤容重最低。综合分析,以常规施肥减施氮肥5%处理效果最佳。     

冬小麦叶片氮含量时空分布及其与植株氮营养状况的关系

以低蛋白小麦品种宁麦9号和高蛋白小麦品种淮麦20为材料,研究了冬小麦不同生育时期冠层叶片氮素时空分布特征及其与植株氮含量的关系。结果表明,叶片氮含量在不同叶位间的分布因生育时期而异,拔节期、抽穗期和开花期叶片氮含量都呈现顶1>顶2>顶3>顶4的趋势,而在药隔期及孕穗期,两品种顶2叶氮含量均大于顶1叶。     

不同施氮量对马铃薯-小麦轮作体系产量及土壤氮素平衡的影响

为了明确不同施氮处理对马铃薯-小麦轮作产量及其土壤养分平衡的影响,在内蒙古马铃薯繁育中心中旗试验基地进行肥力定位试验。以不施肥处理为对照（CK）,设置4个氮肥施用量梯度处理,分别是不施氮肥处理（N0）、减氮2/3处理（ON1）、减氮1/3处理（ON2）、农户习惯施氮处理（FN）,研究马铃薯-小麦轮作产量年际变化以及土壤氮素平衡特征。研究表明：与FN相比,ON2的产量没有降低反而有所增加;同时,ON2的植株氮素吸收积累量高于FN,氮肥生产效率高于FN处理;ON1、ON2的耕层（0~30cm）土壤无机氮残留显著低于FN,而马铃薯-小麦轮作体系中氮素的表观损失主要发生在小麦种植季。本研究初步认为：在内蒙古马铃薯-小麦轮作区氮素过量施用地区,对马铃薯-小麦轮作体系氮肥减施1/3可实现作物的稳产、提高氮素利用率,同时有效降低氮肥对环境污染的风险。     

干旱条件下氮营养对小麦不同抗旱品种生长的影响

在土壤干旱条件下,３米小麦品种叶片水势、饱和渗透势、相对含水量、净光合速率、叶片导度、干物质积累量和籽粒产量均明显降低,且施氮小麦的下降幅度大于不施氮小麦,干旱削弱了氮素营养对小麦生长和产量的促进作用。土壤愈旱,渗透调节作用愈强,适当的氮素营养可增强渗透调节强度,水地型品种对水分和氮素营养均最敏感,其水分状况、游离脯氮酸含量,光合物质生产的产量的变化均较旱地型品种大;旱地型品种受旱时水分状况较稳定     

冬小麦光合速率对施氮量与光照强度的响应分析

为了探索施氮量在不同光照强度下对冬小麦光合速率的影响,基于小区施氮控制试验,设置4个施氮量水平和5个光照强度,分析施氮量对冬小麦叶片氮素含量的响应规律,研究光照强度和叶片氮素对冬小麦叶片净光合速率的影响。结果表明,随施氮量的提高,叶片含氮量逐渐上升,过量施氮会抑制灌浆初期和灌浆中期叶片含氮量的增加;从拔节期-灌浆中期,叶片含氮量总体降低,冬小麦净光合速率随光照强度的增大呈增加趋势,光合速率在低施氮量下先上升后下降,而在不施氮和中、高施氮量下随生育时期推进呈下降趋势;在人工控制的固定光照强度下,冬小麦叶片净光合速率与叶片含氮量呈极显著正相关,即随着叶片含氮量的增加光合速率呈上升趋势,故适量增施氮肥有助于冬小麦光合速率的提高。     

氮肥调控对小麦/玉米产量、氮素利用及农田氮素平衡的影响

为了实现小麦/玉米高产高效生产,采用田间小区试验方法,研究了不同氮肥管理措施对小麦/玉米产量、氮素利用及农田氮素平衡的影响。结果表明,小麦季在农民常规施肥的基础上适当减少追氮量不会对小麦产量产生明显影响,在施氮总量195 kg/hm2基础上配施调控剂处理小麦增产8.3%~24.6%,氮肥偏生产力、表观利用率和农学效率及氮肥贡献率均得到相应提高。在玉米季,以一次性基施适量氮肥同时配施抑制剂的氮肥管理方案为最佳,在施氮240 kg/hm2水平上与不添加抑制剂等氮量一次性基施和基追结合处理相比,增产幅度分别为7.4%~9.6%和13.9%~16.2%,氮肥贡献率、肥料偏生产力和农学效率亦得到显著提高;经过一个轮作周期后,农田土壤氮素盈余量为63.94~126.83 kg/hm2。在总施氮量435 kg/hm2的情况下,与单施尿素相比较,配施氮素调控剂的氮素盈余量降低了27.4%~44.2%,其中脲酶与硝化抑制剂配施效果最佳。但在总施氮量480 kg/hm2的情况下,即使施用了氮素调控剂,氮素平衡盈余率仍在20%以上,存在较大的环境风险。     

氮肥管理与地膜覆盖对旱地冬小麦产量和氮素利用效率的影响

降雨偏少且季节分布不均,施肥偏多且方式不合理,缺少有效的保水栽培措施是西北旱地小麦生产面临的主要问题。2010年10月至2012年6月连续2个小麦生长季,在陕西渭北旱塬进行田间试验,比较了氮肥追施和总量减少、覆膜、增加种植密度措施较传统施肥和农民习惯施肥种植模式对冬小麦籽粒产量及氮素利用效率的影响。与农户习惯施肥相比,传统施肥不能持续增加产量和氮素利用效率;而减氮追肥、减氮垄覆和减氮垄覆增密处理的增产效果明显,同时提高了氮素利用效率,但减氮垄覆或增加种植密度却使籽粒含氮量降低,主要原因是进入开花期后土壤硝态氮累积量减少,氮素供应不足所致。综合分析,减氮垄覆增产增效更明显,小麦产量、氮肥偏生产力、氮肥生理利用率在第1年分别提高38.6%、49.6%和35.1%,在第2年分别提高7.6%、16.3%和25.7%,说明控氮与覆膜结合是实现旱地冬小麦增产的重要措施,但需注意生长后期土壤氮素供应,在增产的同时保证小麦品质。     

The Influence of Crop Rotation with an Increasing Content of Cereals on Photosynthetic Potential of Winter Wheat

In years 1982–1985 flag leaf area, concentration of chlorophyll and macronutrients (N, P, K, Ca, Mg, Na) and also their correlations to grain yield in static field experiment were studied. The main experimental plots comprised crop rotations containing 50, 75, 100% cereals. Treatments with or without irrigation were subplots and nitrogen levels (0, 60, 120, 180 kg N/ha) were sub-sub-plots.
The cultivation of winter wheat in rotations containing more than 50% cereals affected the drop of winter wheat grain yield, which was especially high on the plots without nitrogen fertilization or with low N level. The dose of 120 kg N/ha gave the highest grain yield in each rotation and, at the same time, decreased to minimum the differences between them, although wheat grown in the full cereal rotation yielded much less. The response of wheat grain yield to previous crop was affected by photosynthetic potential of a plant, which was constituated by flag leaf area and concentration of chlorophyll. The deteriorating nutrient economy in wheat plants grown in rotations containing more than 50% cereals decreased the photosynthetic potential of wheat. In addition, in these rotations the importance of macronutrients concentration in the flag leaf at anthesis as a source of nutrients for the developing grain is visible.     

基于多视角反射光谱的冬小麦冠层叶片氮素营养监测研究

通过2个蛋白质含量不同的冬小麦品种和4个氮素水平的试验,研究传感器在垂直冬小麦垄平面上,冠层不同观测角度的反射光谱与叶片氮素营养的关系,改进小麦冠层氮素光谱诊断的理论与方法。结果表明,在本试验选择的7种植被指数光谱特征参量中,2个小麦品种均表现为比值植被指数（RVI[670,890]）与冠层叶片氮素含量（CLNC）相关性最高;不同视角的RVI与冠层叶片氮素含量关系中,0°、30°和90°的相关性最高;利用0°、30°和90°的RVI与CLNC进行模型拟合,其模型的决定系数是0°﹥30°﹥90°;在建立的0°模型中,京411小麦模型RMSE为0.2915,预测准确率为90.2%,中优9507模型RMSE为0.3827,预测准确率为87.2%。本研究证明改变反射光谱观测角度,能够提高冠层叶片氮素含量的光谱预测精度,不同小麦品种其光谱特征与冠层叶片氮素含量关系不同,在应用中要根据不同的小麦品种建立相应的模型。