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1.
The influence of undersown green manure crops for fallows – set-aside land – in view of vegetation-development and the dynamic of nitrate
In view of the establishment of rotational fallows - set-aside land - as well as the bridging of the vegetation-free winter period the suitability of different undersown grasses and legumes m winter cereals was investigated in field trials. Festuca rubra developed well in winter barley and winter wheat. The success of the cultivation of Lolium perenne, Trifolium pratense and Trifolium repens in winter cereals is uncertain because of the risk of light and water deficiences. Dactylis glomerata caused an negative influence on the yield of the cover crop. During the fallow period only low levels of nitrate could be found in the soil. Under fallow tilled repeatedly complete fallow- a nitrate accumulation could be observed during the fallow period. After ploughing up the fallow vegetation, nitrate concentrations - depth 0–150 cm – increased to 60 kg NO3-N · ha-1 after the natural fallow without seeding, between 60 and 130 kg NO3-N · ha-1 after Trifolium and between 160 and 210 kg NO3-N · ha-1 after complete fallow. Lowest nitrate levels were observed from the grass-sites. Undersown Festuca rubra seems to be the best choice in order to compete with weeds, to form a dense sod and to prevent nitrate leaching. In general a seed rate of 8 kg · ha-1 can be recommended.  相似文献   

2.
NO3 dynamics in the soil, yield formation and N uptake of winter wheat as influenced by dosage and distribution effects of N-fertilizer application
In a 4 year series of field trials carried out with 9 regimes of nitrogen fertilizer application at two trial sites with rather shallow top soil layers but large deviations in soil characteristics, grain yield varied between 50 dt/ ha and 120 dt/ha with nitrogen doses from 0–170 kg N/ha. Soil nitrogen supply for wheat grain formation on unfertilized plots reached 80 kg N/ha/year within the narrow range of 75–95 kg N/ha in different years at both sites which amounts to 1.5 % and 0.5 % of the highly different N-content of the trial sites.
The most successful nitrogen application regimes are characterized by modest fertilizer doses in early spring and the delay of supplemental fertilizer doses until growth stage EC 32. They resulted into modest NO) soil content from EC 29 to EC 32 and/or a noticable decrease of soil NO3 content during growth stage EC 30–32, which seems to be responsible for the development of only modest stand densities and reduced straw yield, while the delayed supplementation with nitrogen fertilizer overcompensated these effects mainly by increased grain numbers/ear and a remarkable improvement of harvest index.
The contribution of soil borne nitrogen to kernel yield formation started to decrease with even low dosages of supplemental nitrogen fertilization with the exception of the highest yielding season 1987/88. Top levels of grain yield have been regularly obtained with supplemental nitrogen fertilizer dosages about 40 kg N/ha below grain yield nitrogen extraction if they were added within favorable application regimes.  相似文献   

3.
N-uptake and N utilization of different fertilizer types by winter wheat – pot experiments with 15N
The efficiency of top dressing urea, ammonium nitrate and ammonium sulphate fertilizers on winter wheat grown on loamy sand and loessial black soil was studied. At a rate of 0.5 g N per pot on the loamy sand 20 % volatilization losses of NH3 occurred with urea and 10 % on the loessial black soil with urea resp. ammonium sulphate.
The grain yields an N removal correspond to these results. At an amount of 1.6 g N per pot the N-uptake of 15N ranged from 0.589 g (urea) on sandy soils to 1.279 g (ammonium nitrate) which agrees with 76 % an 91 % of the total N uptake. On black soil 0.675 g (urea) and 1.038 g (ammonium nitrate) or 44 % and 51 % of the total uptake are found.  相似文献   

4.
Determination of net rhizodeposition of winter wheat by means of a respirometrical technique
Net rhizodeposition (root carbon, which is deposited into soil at a chosen harvesting term) may be estimated respirometrically by a laboratory experiment with a root contained soil probe, if microbial decomposition of it is compared to microbial decomposition of a standard root probe of the same origin. Net rhizodeposition therefore is given by This technique was applied to three treatments of a N fertilizer trial with winter wheat. Calculated net rhizodeposition was compared to above ground crop. On an average it amounted to 20 per cent of shoot carbon. Mass and nitrogen content of it increased with increasing quantity of N fertilizer.  相似文献   

5.
耕作和培肥对豫中区冬小麦生长和产量性状的影响   总被引:1,自引:0,他引:1  
以‘百农矮抗58’为试验材料,在2007-2008年度深耕土壤的基础上,于2008-2009年度研究了深耕(耕深40 cm)和浅耕(耕深20 cm)2种耕作方式和底施专用复合肥(B1)、专用复合肥+鸡粪(B2)及专用复合肥+饼肥(B3)3种培肥模式对豫中区冬小麦生长和产量性状的影响。结果表明:浅耕模式下小麦的株高、群体数量、叶片叶绿素含量及地上部单株干物质积累量均高于深耕模式。B3培肥模式下,小麦叶片的叶绿素含量和植株地上部分干物质积累量较高。浅耕+B3模式下成穗数和穗粒数极显著高于其它模式,产量较高。综上,深耕基础上,浅耕配施复合肥和饼肥是豫中区适宜的种植模式。  相似文献   

6.
Foliar fungicides are important management inputs for winter wheat (Triticum aestivum L.) in high-yielding areas of Europe, but their effectiveness may interact with cultivar selection and nitrogen (N) fertilization. No information is available on the potential use of fungicides in reducing yield losses from foliar diseases in Croatia, where wheat crop is extensively grown under low N inputs. Field experiments were conducted during 2000–02 to evaluate the agronomic responses of six winter wheat cultivars to fungicide application (tebuconazol around heading) compared with untreated plots at low (67 kg N ha−1) and high (194 kg N ha−1) N fertilization rates. Grain yields tended to increase in all years following fungicide treatment at high N rate by an average of 10.1 % (773 kg ha−1), but improved significantly in one year only at low N rate. When these occurred, yield increases were associated with larger grain weight per ear primarily due to heavier 1000-kernel weight. Cultivars differed in their responses to fungicide application across growing seasons and N fertilization rates. Under low disease pressure in 2000 and 2001, improved yields with fungicide use occurred for few susceptible cultivars only, whereas all cultivars significantly increased yields under higher disease severity in 2002 by an average of 383 kg ha−1 (5.0 %) at low N rate and 1443 kg ha−1 (19.0 %) at high N rate. Following fungicide application at high N rate, some susceptible cultivars outyielded resistant cultivars, whereas opposite responses occurred in untreated plots. High N fertilization rate consistently produced larger grain yields except under high disease severity and no fungicide sprayed in 2002, when it had no benefits at all over low N rate. Fungicide application showed limited importance for wheat performance at low N rate; however, cultivars significantly differed in yield responses as well as in rankings after fungicide use at high N fertilization rate.  相似文献   

7.
Two-year field trials with winter wheat cultivars Batis and Toronto were conducted in Southern Bavaria, Germany, to investigate the possible causes of cultivar differences in response to N supply varying in total amount and time of application. Cultivar-related differences in grain yields were observed in treatments with low and medium N supply. High doses of N supply resulted in grain yield adjustment or grain yield advantage for cv. Toronto. The results of this study revealed a consistent, genotypic pattern in response to N fertilization in spite of strong seasonal effects. Systematic modifications in canopy growth rates in response to N supply were of particular relevance and a main factor for differences in tillering intensity resulting in modified stand densities. In the present study, cultivar differences in spike development and interactions with N supply related more to abortion than to initiation processes for number of spikelets and number of flowers per spikelet. High grain density (grains per m2) of cv. Toronto was evident during reproduction stages even under conditions of medium N supply. However, decreased growth rates during the later part of grain filling in combination with low 1000 grain weight, which was barely modified by N fertilization, allowed only partial utilization of this potential. It is assumed that sink limitations were of particular relevance for grain yield development in cv. Toronto, while cv. Batis combined a less intense response to N supply with more stability in the development of grain yield components.  相似文献   

8.
为了综合评价稻秸还田方式对冬小麦产量及冻害的影响,以不还田为对照(CK),设置覆盖还田、宽行覆草、浅旋还田、翻耕还田4种还田方式,研究各处理下小麦生长和产量的变化以及对低温的响应。结果表明,与对照相比,覆盖还田和浅旋还田显著降低了冬小麦的出苗、分蘖的发生以及花后干物质的积累,其产量分别减少了21.3%和15.3%,而宽行覆草和翻耕还田则与之相反,分别较对照增产8.0%和5.2%。另外,与对照相比,覆盖还田和浅旋还田不仅显著降低了单株麦苗质量(茎蘖数、鲜重和干重),而且在低温下有更多的冻害苗和更高的冻害比例。相关分析得出,冻害苗数与单株麦苗的质量呈显著负相关。表明通过宽行覆草和翻耕还田2种方式还田均有利于冬小麦生长和产量的形成,并在一定程度上能减轻冬小麦的冻害。  相似文献   

9.
2012—2013年在陕西三原县(水地)和永寿县(旱地)进行土壤扩蓄增容肥应用效果试验,研究了土壤扩蓄增容肥对小麦产量、产量构成因素和品质的影响。结果表明,土壤扩蓄增容肥对冬小麦有极显著的增产作用。水地较对照净增产1304.06 kg/hm2,增产幅度为16.8%;旱地较对照增产224.70 kg/hm2,增产幅度为8.6%。同时,土壤扩蓄增容肥处理的水地小麦多个品质指标较对照显著降低,其中蛋白质含量降低4.2%,硬度降低2.2%,湿面筋含量降低4.6%,沉降值降低11.6%,面团流变学特性中除吸水率外均显著减少;但土壤扩蓄增容肥对旱地小麦品质指标无显著影响。  相似文献   

10.
本研究旨在揭示不同土壤类型条件下,小麦产量对增温的响应规律及特征.试验采用开放式增温系统对冬小麦全生育期进行全天增温,供试土壤为黑土、棕壤、风沙土、潮土、红壤和砖红壤.与常温处理相比,增温处理冬小麦株高、地上干重、穗粒数和产量分别增加了11.5%、17.7%、12.3%和12.8%;增温对生长在不同类型土壤上的小麦株高...  相似文献   

11.
氮肥实时监控技术对冬小麦产量及养分效率的影响   总被引:1,自引:1,他引:1  
为了高效利用氮肥,通过2005-2007年定位试验,应用氮素实时监控技术研究小麦最佳施氮量。结果表明,推荐的施氮量与农户习惯施氮量相比,氮肥的施用量大幅减少,3年累积节约氮肥投入903 kg/hm2。由于该技术实现了氮肥供应与小麦需求的同步,因此,产量较农户习惯施氮增加6.1%,收益增加1833元/hm2,同时,氮肥的利用效率、农学利用率以及偏生产率显著提高,而土体硝态氮的累积与淋洗则大幅下降。小麦应用氮素实时监控技术,可以实现产量增加、养分效率提高及生态环境保护的协调一致。  相似文献   

12.
为了进一步明确冀西北冬麦北移的适宜播期和品种,选用3个冬小麦品种(‘京冬1号’、‘苏引6号’和‘02铁品5’),通过分期播种,研究不同播期对小麦越冬和产量的影响。结果表明,以2008年9月23日为播种期的小麦越冬性和产量最高,播期主要通过影响有效穗数多少决定产量高低,播种越晚影响越明显;‘02铁品5’与‘苏引6号’产量极显著高于‘京冬1号’。通过对2005-2010年的冬前积温进行分析,认为冀西北冬小麦适宜播期为9月20日至9月25日左右,同时,应根据气候及品种特性进行适当调整,即较暖地区可适当延后,冷凉地区要适当提前;生育期短、冬性弱的品种要适当晚播,生育期长和冬性强的品种可适当早播;播期推迟时,要适当加大播种密度,以弥补越冬性差造成的群体不足。  相似文献   

13.
节水减氮对土壤硝态氮分布和冬小麦水氮利用效率的影响   总被引:8,自引:0,他引:8  
针对当前关中平原冬小麦生产中氮肥投入过量、灌溉水资源不足的问题,研究节水减氮栽培模式下冬小麦籽粒产量、水氮利用及硝态氮淋失情况,能为确定冬小麦节水减肥环保增效的生产模式提供理论依据。于2017—2019年在陕西杨凌开展冬小麦节水减氮田间栽培试验,采用二因素裂区设计,施氮量为主处理,灌水量为副处理,设施氮量处理N300 (300 kg hm–2)、N225 (225 kg hm–2)、N150 (150 kg hm–2)、N75 (75 kg hm–2)、N0 (不施氮)和灌水量处理W2 (1200 m3 hm–2)、W1 (600 m3 hm–2)、W0 (0),分析小麦产量、水氮利用效率及土壤硝态氮淋失情况。结果表明,2017—2018年和2018—2019年小麦季灌水处理较不灌水处理分别增产14.88%~15.01%和4.11~4.16倍,但处理间差异不显著,而越冬期灌水600 m3 h...  相似文献   

14.
不同播种措施对河北冬小麦产量影响研究   总被引:1,自引:1,他引:1  
针对河北平原冬小麦生产中大面积采用秸秆还田和旋耕后直接播种给冬小麦出苗带来的不利影响,在河北藁城市进行了冬小麦抢墒播种(对照)、播前灌溉、抢墒播种后镇压3种处理对冬小麦生长发育及产量的影响试验。结果表明,播前灌溉和抢墒播种+播后镇压的产量分别比对照高6.9%和6.0%,与对照处理的产量达到显著差异(P<0.01)。因此,小麦抢墒播种加镇压可节省冬小麦底墒水,具有很好的节水增产效果,可以大面积推广。  相似文献   

15.
The influence of sowing date, seed rate, and variety on agricultural characteristics of winter wheat in a low external input system
Growth conditions of winter wheat in agricultural low external input systems, e.g. ecological agriculture, are very different compared to conventional agriculture (mineral nutrition, impact of diseases, competition of weeds). In 1986, 1987, and 1988 the influence of sowing date and seed rate on crop development and grain production was studied with two varieties of winter wheat in field experiments in Northern Hessia.
Drilling after the first decade of October decreases grain yield of both varieties significantly. The decrease was due to poor emergence, low plant densities, and low grain weights. Tillering could not compensate low plant densities, presumably because of low mineralization of nutrients in cold soils during respective growth stages.
Variation of seed rate (350, 500, and 650 viable seeds/m2) had little influence on grain yield. Low plant densities and low numbers of ears per nr after sowing in the end of October could not be improved satisfactorily by increased seed rates.
The ability of varieties of winter wheat to compensate unfavourable growth conditions due to "late" sowing varies considerably. Cultivars which are able to develop a high plant density seem to be more suitable for delayed sowing dates, as compared to varieties which own a high grain weight.
Further investigations concerning wheat production are needed to optimize agricultural low external input systems. Especially sandy soils with quick response to increased ambient temperature, and sites with favourable growth conditions in late autumn and early spring should be considered.  相似文献   

16.
微喷补灌对麦田土壤物理性状及冬小麦耗水和产量的影响   总被引:3,自引:0,他引:3  
何昕楠  林祥  谷淑波  王东 《作物学报》2019,45(6):879-892
黄淮海麦区水资源短缺,探明畦灌和微喷补灌对麦田土壤物理性状及冬小麦耗水特性、产量和水分利用效率调节的差异,可为该地区冬小麦节水高产栽培提供理论和技术支持。2016—2018年冬小麦生长季,设置畦灌和微喷补灌两处理,研究其对麦田0~40 cm土层土壤容重、总孔隙度、毛管孔隙度、田间持水率,及冬小麦各生育阶段棵间蒸发量、蒸腾量、籽粒产量和水分利用效率的影响。结果表明微喷补灌处理与畦灌处理相比, 0~20 cm土层土壤容重降低,总孔隙度、毛管孔隙度和田间持水率增加;冬小麦返青后春季分蘖明显减少,返青至拔节期的棵间蒸发量和蒸腾量及全生育期总耗水量均显著减少;籽粒产量无明显变化,但水分利用效率显著提高,说明微喷补灌可以改善麦田土壤物理性状,优化冬小麦群体结构,通过减少棵间蒸发和植株无效蒸腾降低麦田耗水量,从而在维持高产水平的同时提高水分利用效率。  相似文献   

17.
为了研究浮山县7—9月夏闲期降水量对翌年冬小麦产量的影响,做出翌年小麦产量的趋势预报,提出相应措施和对策,指导小麦生产趋利避害。通过对山西省浮山县1980—2009年7—9月夏闲期降水量与翌年冬小麦产量的分析,利用SPSS软件,分离趋势产量和气象产量,建立小麦趋势产量回归方程;通过气象产量与夏闲期降水量的分析,建立两者的对数方程,最终建立小麦产量预报模型:Y=2.995T+68.102lnX-254.578。结果表明:浮山县1980—2009年7—9月夏闲期降水量与翌年冬小麦产量拟合率较高,预测精度最高为99%,平均预测精度为80%。通过研究得出:浮山县7—9月降水量与翌年冬小麦产量相关性显著,预测精度较高,但因未考虑到小麦生育期降水量的影响,故如遇较大范围严重自然灾害时,预测精度会大大降低。  相似文献   

18.
Experiments were conducted to evaluate the effect of mouldboard‐ or chisel‐ploughing and rotations on barley crops and associated weeds in a semi‐arid location. Two primary soil tillage operations and eight crop rotation‐tillage operation combinations were evaluated over two successive seasons. Drought conditions prevailed (<152 mm annual precipitation) and affected the measured parameters. Barley grown in mouldboard‐ploughed plots had higher biomass compared with chisel‐ploughed plots. Barley grain yield was greater in mouldboard‐ploughed plots in a fallow‐fallow‐barley rotation. Weed species densities varied between tillage systems and rotations. Density of Hordeum marinum, for example, was high in fallow‐barley‐fallow in chisel‐ploughed plots, and was high under more continuous fallow in mouldboard‐ploughed plots. Similar variations were also observed in weed fresh weights and in numbers of seed produced. The results describe the productivity of barley under extremely dry conditions, where an advantage for mouldboard ploughing was observed. The results also indicate the complexity of weed communities in their response towards different tillage‐rotation combinations.  相似文献   

19.
在大田条件下研究了小麦秸秆不同还田深度下小麦蔗糖含量及其有关酶活性,结果表明秸秆还田处理条件下,灌浆期间旗叶蔗糖含量及磷酸蔗糖还原酶(SPS)活性、籽粒蔗糖含量和酸性转化酶(AI)活性均高于普通耕作处理。在各不同深度秸秆还田处理中,15 cm深度秸秆处理在灌浆前期上述指标均有较高的表现,而花后21 天左右则低于还田25 cm处理,灌浆后期下降幅度较大;而穗下节间蔗糖含量还田25 cm 处理在花后7 天左右超过其他处理,因而蔗糖滞留量较高。在秸秆还田25 cm 处理条件下,小麦籽粒产量达到最高,其穗数也最多,而穗粒数与15 cm还田处理差异不显著,千粒质量也较低。  相似文献   

20.
冬小麦田间水分反应特性产量评价指标研究   总被引:3,自引:0,他引:3  
摘要:【目的】为全面有效地评价冬小麦品种对水分的反应特性。【方法】根据2007年和2008年不同小麦品种大田灌水试验的结果分析了抗旱系数(DC)、抗旱指数(DRI)、干旱产量指数(DYI)、丰水产量指数(WYI)、产量-水分高效利用指数(YWI)、水分适宜指数(WAI)和产量系数(YC)的适用性。【结果】DC反映品种的水分敏感性;DRI适合筛选旱地产量高且灌水增产不显著的品种;DYI较好的反映干旱条件下的产量,WYI能够反映不同品种的灌水效率差异,YWI适合筛选干旱条件和灌水条件下产量较高的种质。WAI适合参试品种间相对比较,但对同一品种适水性的评价效果因品种而异。产量系数(YC)适于组内筛选抗旱品种、高产品种和某灌水条件下水分高效型品种。【结论】初步提出多指标评价品种水分反应特性的方法和统一的分级标准。提出在合理选用对照种和明确水分鉴定条件的前提下,采用干旱产量指数修订值鉴定品种的抗旱性,用丰水产量指数修订值鉴定各水分条件下品种的水分高效性,用各水分条件下品种的平均产量相对值鉴定品种的高产性,采用阶段敏感指数鉴定不同生育期的水分敏感性,采用产量系数修订值鉴定品种的适水性。  相似文献   

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