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1.
土壤水分对冬小麦生长后期光能利用及水分利用效率的影响   总被引:15,自引:4,他引:15  
通过控制不同土壤水分条件形成不同的小麦(Triticum aestivum L.)群体结构,测定了抽穗到成熟期间小麦冠层光合有效辐射(PAR)截获及垂直分布、干物质积累和产量。研究表明,不同处理小麦冠层对PAR的截获量差异较小(小于15.7%),但冠层上部(60~80 cm)的PAR截获量和生长后期PAR转化效率差异明显(100.7%和63.7%),与产量和光能利用效率变化一致,可见土壤水分是通过改变小麦群体内PAR垂直分布及PAR转化效率对作物产量和光能利用效率产生影响。抽穗到成熟期间维持小麦冠层上部PAR截获率在50%左右是实现高产的重要保证。随着土壤水分改善,冬小麦光能利用率和产量持续增加,但水分利用效率却先于二者提前降低,说明改善水分利用效率是提高华北地区农业气候资源利用效率的关键。在底墒充足的条件下,分别在拔节和挑旗期灌水60 mm可获得较高的光能和水分利用效率及经济产量  相似文献   

2.
Radiation use by oil seed crops — a comparison of winter rape, linseed and sunflower For the production of grain crops rich in oil, winter rape, linseed and sunflower are similarly suitable at many arable locations. We wanted to compare the extent to which radiation (PAR) is intercepted and utilized by the individual species for dry matter and yield production. For this purpose, a 2‐year field experiment comprising the factors genotype, N fertilization and soil tillage was conducted. For five phases of crop development, growth rates (CGR, RGR and NAR) and PAR utilization were calculated. At full ripeness, total dry matter, grain, oil and energy yields, the crop‐ and year‐specific PAR supply, its interception and utilization for dry matter production and the resulting energy binding were determined. Due to the different individual vegetation periods, the PAR supply of the crops differed. The crop assimilation areas also differed, with values for winter rape and sunflower higher than those for linseed. The yield productivity of winter rape and sunflower was also higher than that of linseed. N fertilization increased yield to different extents for the different crops. On average, winter rape and sunflower produced the same amounts of dry matter and energy yield. Due to a higher harvest index, sunflower had the highest grain yield, and because the oil concentration in grain was comparatively high sunflower produced the highest oil yield, too. Under cool and wet climate conditions, however, the productivity of sunflower is offset by a relatively high yield risk because of uncertain ripening. The highest PAR utilization by linseed did not compensate for its very short vegetation period in combination with the lowest PAR interception.  相似文献   

3.
为了进一步明确黄淮平原冬小麦晚播、夏玉米晚收的“双晚”增产及资源高效的效应,选用2个中熟冬小麦品种和2个中晚熟夏玉米品种,于2006—2008年先后在河南温县和焦作进行大田试验,研究作物群体物质生产、产量形成参数定量指标及光温资源的分配利用。结果表明,冬小麦晚播产量降低不明显,夏玉米晚收产量显著提高747~2 700 kg hm-2,“双晚”周年产量21 891~22 507 kg hm-2,比对照提高442~2 575 kg hm-2。冬小麦晚播平均叶面积指数、每平方米穗数和穗粒数降低,但平均净同化率、收获指数和粒重提高达5%显著水平;夏玉米晚收平均叶面积指数、收获指数、生育期天数和粒重均显著提高。“双晚”栽培优化了周年资源分配,提高生育期与光、温资源变化的吻合度,其生产效率分别提高2.22%~10.86%和0.47%~11.56%。小麦和玉米品种的遗传类型是影响“双晚”栽培技术的关键。因此,选用小麦晚播早熟高产和玉米长生育期晚熟品种,通过有效调节资源配置,将小麦冗余的光温资源分配给C4高光效作物玉米,是提高周年高产高效的重要途径。  相似文献   

4.
Data from a field experiment (1995–2000) conducted on a fertile sandy loess in the Hercynian dry region of central Germany were used to determine the energy efficiency of winter oilseed rape (Brassica napus L.) as affected by previous crop and nitrogen (N) fertilization. Depending on the previous crop, winter oilseed rate was cultivated in two different crop rotations: (1) winter barley (Hordeum vulgare L.)–winter oilseed rape–winter wheat (Triticum aestivum L.), and (2) pea (Pisum sativum L.)–winter oilseed rape–winter wheat. Fertilizer was applied to winter oilseed rape as either calcium ammonium nitrate (CAN) or cattle manure slurry. The N rates applied to winter oilseed rape corresponded to 0, 80, 160 and 240 kg N ha−1 a−1.Results revealed that different N management strategies influenced the energy balance of winter oilseed rape. Averaged across years, the input of energy to winter oilseed rape was highly variable ranging from 7.42 to 16.1 GJ ha−1. Lowest energy input occurred when unfertilized winter oilseed rape followed winter barley, while the highest value was obtained when winter oilseed rape received 240 kg N ha−1 organic fertilization and followed winter barley. The lowest energy output (174 GJ ha−1), energy from seed and straw of winter oilseed rape, was observed when winter oilseed rape receiving 80 kg N ha−1 as organic fertilizer followed winter barley. The energy output increased to 262 GJ ha−1 for winter oilseed rape receiving 240 kg N ha−1 as mineral fertilizer followed pea. The energy efficiency was determined using the parameters energy gain (net energy output), energy intensity (energy input per unit grain equivalent GE; term GE is used to express the contribution that crops make to the nutrition of monogastric beings), and output/input ratio. The most favourable N rate for maximizing energy gain (250 GJ ha−1) was 240 kg N ha−1, while that needed for minimum energy intensity (91.3 MJ GE−1) was 80 kg N ha−1 and for maximum output/input ratio (29.8) was 0 kg N ha−1.  相似文献   

5.
氮钾配施对油菜产量及氮素利用的影响   总被引:2,自引:0,他引:2  
实际生产中氮钾肥投入不平衡严重限制了氮肥肥效及作物的产量潜力。为了探明不同施氮量下钾肥施用对油菜产量及氮素利用的影响,于2016—2017年及2017—2018年在湖北省武穴市开展连续2年的田间试验,采用氮钾两因素完全试验设计,设氮0、90、180、270 kg N hm-2和钾0、60、120、180 kg K2O hm-2各4个水平。在油菜成熟期取样测定产量、地上部氮钾积累量以及氮肥利用率。结果表明,在钾供应不足时(K0和K60),冬油菜施用氮肥的平均增产率为113.7%,而在钾供应充足的条件下(K120和K180),施用氮肥的平均增产率高达172.9%;与K0处理相比, K120处理冬油菜氮肥回收利用率平均提高了16.6%,继续增施钾肥对不同施氮量下冬油菜氮肥回收利用率的进一步提高无显著影响;达到区域平均产量时,钾供应充足较低钾(K60)投入平均降低33.9%的氮肥用量。综上所述,氮钾配施显著提高了冬油菜产量和氮肥利用率,在冬油菜实际生产中除了重视氮肥施用外,应增加钾肥投入,通过优化氮钾肥配施比例可进一步提高油菜产量,实现冬油菜高产和养分高效。  相似文献   

6.
Manfred Huehn 《Euphytica》1993,68(1-2):27-32
Summary The variation of the two parameters, harvest index and grain/straw-ratio, has been theoretically compared by applying the relative measure coefficient of variation. The harvest index exhibits a clear superiority (= lower variation) compared to the grain/straw-ratio.Applications to ten European winter oilseed rape cultivars and lines are in an excellent agreement with the theoretical findings.  相似文献   

7.
Grain yield and yield components of winter wheat were recorded during 2-year field trials in Southern Bavaria, Germany. The impact of single ear sink size on the efficiency of grain production was studied in plants differing in single ear weight. While total grain yield showed only slight differences between N fertiliser treatments, significant variations were detected in harvest index and N harvest index. For single culms, a decrease in ear weight was related to decreasing values of harvest index and N harvest index. This correlation could not be altered by means of N fertilisation. The most efficient grain production, i.e. high value of harvest index and N harvest index, was regularly recorded in plant stands developing large single ear weights. The study confirms that with increasing sink size, the efficiency of grain production in winter wheat is improved. A N fertilisation strategy, favouring the formation of a large sink size, is described. In this respect, lower N rates in early spring and emphasis on N fertilisation during stem elongation proved to be decisive. This strategy favoured the generative growth at the expense of vegetative growth without excessively decreasing the corresponding source size.  相似文献   

8.
Yield increases by fertilizer application impose higher crop water use, as biomass production is positively correlated with transpiration. To quantify effects of N fertilizer supply on evapotranspiration (ET) of winter wheat, a field experiment with three nitrogen rates (N0, N120 and N230) under non-water-limited conditions was performed during 2014 and 2015. Normalized difference vegetation index (NDVI) was used to derive crop coefficients which were used to calculate N effects on bare soil evaporation (E), transpiration, evapotranspiration (ET), grain yield and harvest index (HI). E during the early post-winter growth period was measured with micro-lysimeters and compared with model estimates. N fertilizer supply resulted in lower cumulative E, and increases in grain yield were higher than increases in ET, resulting in a higher agronomic water-use efficiency (WUEY). HI of treatment N120 was higher than that of treatment N230 indicating that HI was not the main reason of higher WUEY of treatment N230. It is concluded that estimates of ET under variable N supply require consideration of N-induced effects on canopy development which could be successfully monitored by NDVI measurements. N supply increases ET and WUEY potentially imposing a trade-off between water conservation and efficiency of water use for crop production.  相似文献   

9.
A model to describe the importance of different physiological processes to explain grain yield differences (ΔGw) between cropping systems (Huggins and Pan, 1993) was modified to evaluate the nitrogen use efficiency of different cereals. The method uses measurements of grain yield (Gw), grain N (Ng), above-ground plant biomass (B), above-ground plant N (Nt), applied fertilizer N (Nf), and post-harvest inorganic soil N in control plots without fertilizer (Nh). The components are N supply (Ns), N uptake efficiency (Nt/Ns), assimilation efficiency (B/Nt), harvest index (Gw/B) and N harvest index (Ng/Nt). For a first verification of the model different winter cereal species, i.e., one genotype of winter wheat, one of winter rye and one of spelt wheat, were compared in a 2-year field experiments at two sites with different soil fertility and climate. The modified nitrogen efficiency component analysis provided a good understanding of yield differences at different levels of applied N and soil fertility. The method could be useful for selection of genotypes with a high N use efficiency in breeding programmes.  相似文献   

10.
Improving current cultural practices often involves more precise timing of the management activity based on crop development. Using crop simulation models to predict crop development and phenology has several problems. First, most existing models do not simulate sufficient developmental and phenological detail required to optimize selected management practices. Second, crop models normally emphasize the cultivars and conditions for the region in which they were developed, and may not generate satisfactory results when applied in new regions. Lastly, when users apply these models to new regions they often lack the specific data and knowledge of the model to adequately determine the crop parameters. Our objective was to assess whether the simulation model SHOOTGRO 4.0, which had the necessary level of developmental and phenological detail required for use as a management decision aid, could be easily and adequately parameterized to simulate winter wheat phenology and grain yield in the Czech Republic. We found that only a few parameters from the generic winter wheat cultivar used for the Central Great Plains in the USA needed to be changed, and the information needed to determine these few parameters were readily obtainable. The result was that the dates of anthesis and physiological maturity and final grain yield were predicted well at sites within the three major crop production regions of the Czech Republic. Sensitivity analysis also showed that the most sensitive management practices and initial conditions in SHOOTGRO are relatively easy to determine (e.g. sowing date, N fertilizer rate and timing, daily temperature), while it is not overly sensitive to those variables more difficult to determine (e.g. initial soil water in the profile). Based on this study, farmers and scientists needing wheat development information to increase the efficacy of their management practices can use SHOOTGRO 4.0 as a tool.  相似文献   

11.
Realistic estimation of grain nitrogen (N; N in grain yield) is crucial for assessing N management in crop rotations, but there is little information on the performance of commonly used crop models for simulating grain N. Therefore, the objectives of the study were to (1) test if continuous simulation (multi-year) performs better than single year simulation, (2) assess if calibration improves model performance at different calibration levels, and (3) investigate if a multi-model ensemble can substantially reduce uncertainty in reproducing grain N. For this purpose, 12 models were applied simulating different treatments (catch crops, CO2 concentrations, irrigation, N application, residues and tillage) in four multi-year rotation experiments in Europe to assess modelling accuracy. Seven grain and seed crops in four rotation systems in Europe were included in the study, namely winter wheat, winter barley, spring barley, spring oat, winter rye, pea and winter oilseed rape. Our results indicate that the higher level of calibration significantly increased the quality of the simulation for grain N. In addition, models performed better in predicting grain N of winter wheat, winter barley and spring barley compared to spring oat, winter rye, pea and winter oilseed rape. For each crop, the use of the ensemble mean significantly reduced the mean absolute percentage error (MAPE) between simulations and observations to less than 15%, thus a multi–model ensemble can more precisely predict grain N than a random single model. Models correctly simulated the effects of enhanced N input on grain N of winter wheat and winter barley, whereas effects of tillage and irrigation were less well estimated. However, the use of continuous simulation did not improve the simulations as compared to single year simulation based on the multi-year performance, which suggests needs for further model improvements of crop rotation effects.  相似文献   

12.
冬小麦限水灌溉条件下磷肥补偿效应的研究   总被引:9,自引:1,他引:8  
为探索磷肥对土壤水分亏缺的补偿效应,研究了灌水和施磷对冬小麦耗水和产量等的影响。结果表明,冬小麦总耗水量与灌水量成正相关关系,而土壤贮水肖耗量与灌水量成负相关关系;施磷能提高作物耗水量,促进深层土壤水分的消耗。灌水和施磷均能显著提高冬小麦产量;两者相比,灌水增加了单位面积穗数和提高了千粒重,而施磷仅增加了穗数。灌水对经济系数无明显影响,但明显降低水分利用效率;施磷对经济系数和水分利用效率均无明显影  相似文献   

13.
长江流域直播冬油菜氮磷钾硼肥施用效果   总被引:16,自引:1,他引:16  
冬油菜直播种植的推广应用对提高我国油菜籽总产量和保障食用油安全有重要意义。2009-2010年度在长江流域6个冬油菜主产省布置36个大田试验,研究当前生产条件下我国直播冬油菜的氮磷钾硼肥施用效果和肥料利用率,比较农民习惯施肥与推荐施肥的差异,并与移栽油菜施肥效果进行对比,以探讨直播冬油菜的施肥管理措施。结果显示,在推荐施肥量和施肥方法条件下,氮磷钾硼肥配合施用(NPKB)处理直播冬油菜的油菜籽产量和产值平均分别为2001 kghm–2和8205元hm–2,显著高于农民习惯施肥(FFP)处理,施用效果为N > P > B > K。NPKB配合施用显著促进直播冬油菜的养分吸收,N、P、K累积量分别为104.2、20.4和160.2 kg hm2。NPKB配施条件下,直播冬油菜的氮、磷、钾肥表观利用率平均分别为35.8%、22.3%和45.9%,明显高于农民习惯施肥的20.8%、7.2%和28.0%。说明合理施肥对直播冬油菜生产有重要作用,现阶段应积极推行氮磷钾硼肥配施技术,并根据生长发育特点和养分吸收规律调整肥料的施用时期和比例。  相似文献   

14.
施氮量对垄作小麦氮肥利用率和土壤硝态氮含量的影响   总被引:10,自引:0,他引:10  
以平作为对照,研究了垄作种植方式下施氮量对冬小麦氮肥吸收利用、0~100 cm土层土壤硝态氮含量以及产量的影响。在一定范围内增加施氮量,小麦的氮肥利用率降低,土壤氮的贡献率降低,小麦植株内的氮素积累量增加,收获指数提高,产量增加。低氮(0~66 kg hm-2)条件下,小麦生育期间土壤硝态氮淋洗损失的可能小,小麦收获后0~100 cm土体内不会累积大量硝态氮。施氮量在165~264 kg hm-2时,60~100 cm土体内土壤硝态氮含量增加,出现硝态氮下移趋势。种植方式影响小麦的氮肥利用效率,垄作种植小麦氮肥利用率和产量均高于平作小麦。垄作种植麦田60~80 cm土体内土壤硝态氮含量相对较高,而平作种植麦田80~100 cm土层硝态氮含量相对较高。种植方式对氮肥利用率的影响大于施氮量的影响, 但施氮量对氮素收获指数、籽粒产量以及经济系数的影响大于种植方式的影响。本试验条件下,2种种植方式在施氮量为纯氮165 kg hm-2时可以获得较高的氮肥利用率和氮素收获指数,平作小麦氮肥利用率为35.75%~36.41%,而垄作小麦为45.32%~47.25%; 但2种种植方式的小麦都是施氮量为纯氮264 kg hm-2时获得最高产量, 平作和垄作小麦的最高产量分别达8 078.31 kg hm-2
8 212.27 kg hm-2。  相似文献   

15.
为探明冬小麦和春小麦产量形成差异,2016年10月-2017年6月以冬小麦品种济麦22和春小麦品种津强8号为材料,在大田条件下研究了冬小麦和春小麦生育期、叶面积指数、干物质积累及产量构成。结果表明,春小麦出苗比冬小麦延长8d,营养生长期缩短77~78d,灌浆期延长1~2d,全生育期缩短143~144d。拔节期和开花期,春小麦和冬小麦的叶面积指数无显著差异,但灌浆期春小麦叶面积指数比冬小麦叶面积指数增加6.34%~7.67%,不同生育时期春小麦和冬小麦干物质积累量无差异。春小麦收获穗数和千粒重比冬小麦分别增加2.35%~5.29%和4.28%~5.13%,但穗粒数比冬小麦少1.4~2.3,春小麦与冬小麦理论产量和实际产量均无显著差异。综上所述,春小麦可通过增加播量,增加穗数,保持稳定的叶面积指数和干物质积累量,实现小麦稳产,可为区域变革麦-玉种植制度,实现麦-玉周年双机收子粒提供理论支撑。  相似文献   

16.
不同作物秸秆腐解液对节节麦种子萌发和幼苗生长的影响   总被引:1,自引:1,他引:0  
节节麦(Aegilops tauschii Coss.)作为麦田恶性杂草之一,给中国小麦生产带来了严重的经济损失。为探究农作物秸秆在节节麦生态防治方面的作用,本试验采用了滤纸培养皿法和小杯法研究了不同浓度的玉米、油菜、水稻秸秆及稻壳腐解液对节节麦种子萌发率、发芽指数及幼苗根长、苗高和干重5项生物指标的影响。结果表明,当浓度为6.25 mg/mL时,玉米、油菜秸秆腐解液对节节麦幼苗干重表现为促进作用,对其他测定指标均为抑制作用。稻壳腐解液除了对根长具有抑制作用外,对其他指标均具有促进作用。水稻秸秆腐解液对5项指标均具有促进作用。当浓度大于50 mg/mL时,4种秸秆腐解液对5项指标均具有抑制作用,且随着浓度的增加,抑制作用增强。总体来说,作物秸秆腐解液对节节麦的化感作用强弱依次为玉米秸秆、油菜秸秆、稻壳、水稻秸秆,且对根的化感作用尤为明显。  相似文献   

17.
Previous studies from regions that produce high proportions of global winter wheat have highlighted that difference in sink size influences the majority of variations in winter wheat yield. However, the potential for source limitation due to environmental differences in regions that consistently produce a large sink capacity (i.e. >20,000 grains/m2), such as Ireland, have not been widely studied. The aim of this study was to characterise the variation in growth pattern and yield components that contribute to variations in grain yield in regions of high yield potential, and to identify the periods of development that are most likely to influence yield in these regions. Monitor crops of winter wheat were grown at three sites with contrasting latitudes on the island of Ireland, during three growing seasons (2013–2015). Crops were assessed regularly for measurements of crop growth and development, including biomass accumulation, canopy development and light interception. Grain yield ranged between 10.7–15.8 t/ha at 15% moisture content, with a grand mean of 12.7 t/ha. Results indicated that variations in grains/m2 had a larger effect on winter wheat yield than variations in individual grain weight. Variability in grains/m2 was influenced by changes in spikes/m2 more than the number of grains/spike. While spikes/m2 at harvest was significantly related to the number of shoots/m2 at GS59, no significant relationship was observed between the shoots/m2 at the time of maximum tillers/plant and spikes/m2 at harvest. Furthermore, a significantly negative linear relationship was observed between shoots/m2 at the time of maximum tillers/plant and grains/spike. Therefore, high rates of tillering were not beneficial to yield formation in the majority of crops monitored. A strong effect of individual grain weight was observed at one site of the nine evaluated in the study, indicating that a partial source limitation of yield is possible in certain Irish environmental conditions. However, variations in grain yield of crops of winter wheat grown at different locations in Ireland in different seasons were primarily driven by variations in grain number, and therefore were generally sink-limited.  相似文献   

18.
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.  相似文献   

19.
To compare the statistical properties of harvest index and grain/straw-ratio their variabilities (expressed by the relative measure coefficient of variation), their skewnesses and kurtoses have been compared theoretically.
With regard to variability, the harvest index exhibits a clear superiority (= smaller variability) compared to the grain/straw-ratio. For skewness and kurtosis no such generally valid relationships exist. But, for the range of the empirically most relevant parameter values one obtains approximately equal numerical values for skewness as well as for kurtosis of harvest index and grain/straw-ratio. Finally, the theoretical results and conclusions have been checked and applied to the experimental data sets from a field trial with ten European cultivars/lines of winter oilseed rape.  相似文献   

20.
不同控失肥对冬小麦产量和肥料农学效率的影响   总被引:3,自引:0,他引:3  
基于控失肥养分流失低的特点,研究环渤海低平原区施用控失肥对冬小麦产量及其构成要素和肥料农学效率的影响,以期为环渤海低平原区粮食节水增产提供理论基础。在冬小麦生育期内,选择不同类型控失肥N-P2O5-K2O:16-45-0(K1)和N-P2O5-K2O:24-12-12(K2),并设置当地常规施肥(CF)和不施肥(CK)作为对照,于冬小麦收获期取样考种并测产。结果表明:在保证N和P2O5施肥量同当地施肥量基本一致、仅灌一次底墒水或无灌水条件下,施用控失肥冬小麦产量提高了17%~29%,且不同类型控失肥对冬小麦产量无显著影响;与当地常规施肥、拔节期灌溉的冬小麦产量相比,施用控失肥仅灌一次底墒水时,冬小麦的产量降低了10%~19%,但减少了1次灌水,可节省淡水灌溉量900~1 200 m~3/hm~2;控失肥可以显著提高肥料农学效率和肥料贡献率。相比常规肥料,控失肥的肥料农学效率均提高了71%~228%,肥料贡献率提高了53%。在环渤海低平原区小麦生产中施用新型环保控失肥可达到增产的效果,同时可提高肥料利用效率,减少肥料的流失。在劳动力较少的情况,可将控失肥作底肥一次性施入,减少追肥的劳动力成本。在淡水资源非常紧缺时,保证冬小麦齐苗后,雨养条件下通过施用控失肥,也可保证获得80%以上的冬小麦产量。  相似文献   

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