Assessment of yield monitoring equipment for dry matter and yield of corn silage and alfalfa/grass

Whole farm evaluations have shown that accurate yield data are difficult to collect for alfalfa (Medicago sativa L.) and grass mixtures and corn (Zea mays L.) silage fields. Additionally, on-farm research, a recommended tool for adaptive management, is hindered by lack of practical ways to collect yield data. Recently, forage yield monitors have become available on self-propelled forage harvesters (SPFHs), but precision and accuracy of this technology are unknown. The objective of this project was to evaluate accuracy of yield and moisture sensing components of forage yield monitors for use in alfalfa/grass and corn silage. Moisture content, mass flow weights, total area harvested and total dry yield per hectare were measured on 11 farms in 2013; forage samples were collected for truck loads, analyzed for dry matter content, and compared to monitor-registered dry matter. Truck weights were used to compare monitor-derived yield to actual yield on two farms for alfalfa/grass and three farms for corn silage. Moisture sensors estimated crop moisture content within 3.7 % DM for alfalfa/grass and 3.0 % DM for corn silage of the oven dry value. Flow sensors estimated alfalfa/grass yield to ±0.5 and ±1.1 Mg DM/ha for corn silage. When calibrations are done regularly, forage yield monitors can provide an accurate and precise measure of dry yield for adaptive management. It is concluded that this technology can be used when plots are large and large treatment-driven yield differences are expected.     

基于食物能量安全的马铃薯主粮化实证研究——以宁夏南部山区为例

随着国家马铃薯主粮化战略的实施,马铃薯在保障国家粮食安全中的地位不断提高,基于食物能量安全标准,以宁夏南部山区6区县(原州区、西吉县、隆德县、泾源县、彭阳县和海原县)为例,研究马铃薯主粮化对粮食安全和其他大宗作物的影响。结果表明:西北旱作一年一熟制区马铃薯单产(鲜重)玉米小麦豆类,隆德县和泾源县马铃薯单产分别达到18.16 t/hm2和18.01 t/hm2,高于全国平均水平;现有单产水平下,单位面积马铃薯生产虚拟水小于玉米、小麦和豆类;单位耕地面积马铃薯生产食物能量显著高于小麦和豆类,而低于玉米;马铃薯可实现增产潜力以彭阳县和海原县较大,分别为10.22 t/hm2和12.27 t/hm2,大于玉米和小麦可实现增产潜力;当一个地区马铃薯单位面积产量超过小麦的3.8倍、玉米的4.1倍、豆类的4.7倍时,单位面积马铃薯生产食物能量才能超过小麦、玉米和大豆。因此,黄土高原旱区发展马铃薯主粮化需谨慎,不同农业区域应根据农业结构、粮食单产及可实现粮食生产潜力的具体情况,确定马铃薯的主粮位置,以免造成耕地生产食物能量总量下降,威胁到区域粮食安全。     

天水市农业气象灾害对主要粮食作物生产影响的量化评估研究

通过分析1978～2007年30年影响农作物（冬小麦、玉米为例）生产的干旱、春季低温冻（冷）害、春夏连阴雨、暴雨、冰雹5种农业气象灾害成灾变异率和相应的影响权重,进行了天水主要农业气象灾害灾情综合评价与年景评估。并采用统计学原理逐步回归和多因子回归的方法建立了影响天水市主要粮食作物生产的农业气象灾害量化评估模型,进行了农业气象灾害的量化评估,为有效防御农业气象灾害,最大限度减轻或减免农业损失提供了参考。     

Developing a new Crop Circle active canopy sensor-based precision nitrogen management strategy for winter wheat in North China Plain

Active canopy sensor (ACS)—based precision nitrogen (N) management (PNM) is a promising strategy to improve crop N use efficiency (NUE). The GreenSeeker (GS) sensor with two fixed bands has been applied to improve winter wheat (Triticum aestivum L.) N management in North China Plain (NCP). The Crop Circle (CC) ACS-470 active sensor is user configurable with three wavebands. The objective of this study was to develop a CC ACS-470 sensor-based PNM strategy for winter wheat in NCP and compare it with GS sensor-based N management strategy, soil N_min test-based in-season N management strategy and conventional farmer’s practice. Four site-years of field N rate experiments were conducted from 2009 to 2013 to identify optimum CC vegetation indices for estimating early season winter wheat plant N uptake (PNU) and grain yield in Quzhou Experiment Station of China Agricultural University located in Hebei province of NCP. Another nine on-farm experiments were conducted at three different villages in Quzhou County in 2012/2013 to evaluate the performance of the developed N management strategy. The results indicated that the CC ACS-470 sensor could significantly improve estimation of early season PNU (R² = 0.78) and grain yield (R² = 0.62) of winter wheat over GS sensor (R² = 0.60 and 0.33, respectively). All three in-season N management strategies achieved similar grain yield as compared with farmer’s practice. The three PNM strategies all significantly reduced N application rates and increased N partial factor productivity (PFP) by an average of 61–67 %. It is concluded that the CC sensor can improve estimation of early season winter wheat PNU and grain yield as compared to the GS sensor, but the PNM strategies based on these two sensors perform equally well for improving winter wheat NUE in NCP. More studies are needed to further develop and evaluate these active sensor-based PNM strategies under more diverse on-farm conditions.     

丘陵旱地一年两熟制条件下小麦、玉米阶段耗水量研究

以野外定位观测的方法,对河南省辉县市张村的冬小麦耗水量进行了测定。结果表明,小麦在4500～6000kg/hm2产量水平下,耗水量216.3～345.2mm,播种-返青、返青-抽穗、抽穗-成熟不同生育阶段耗水量分别占全生育期总耗水量的25.9%～36.9%、22.0%～31.1%、31.9%～52.2%,但年际间变幅悬殊较大;夏玉米在6750～7500kg/hm2产量水平下,耗水量为299.6～462mm,分别占同期自然降水量的81.3%～97.4%,播种-拔节、拔节-大喇叭口、大喇叭口-成熟不同生育阶段耗水量分别占全生育期总耗水量的17.1%～17.3%、34.5%～39.1%、43.6%～48.4%。小麦、玉米拔节以后耗水强度明显增加,拔节期、灌浆期是小麦2个重要的水分需求期,大喇叭口期是玉米的重要水分需求期,在目前河南省中北部丘陵旱地,自然降水对玉米水分保证率较高,而对小麦保证率较低,节水补灌重点应放在夏粮作物上。     

陕西省玉米小麦地膜覆盖栽培技术的应用与推广

在回顾总结近１０年陕西省玉米、小麦地膜覆盖栽培技术推广应用的基础上,指出该项技术增产潜力大,适宜区域广,不仅为陕西省粮食增产带来巨大的经济、社会效益,而且成为今后陕西省特别是黄土高原粮食生产上新台阶的重大科技战略措施。同时,提出了加快地膜覆盖技术推广工作的主要措施。     

河北省谷子单产水平变化与成因分析

以1949-2010年河北省谷子、小麦、玉米单产数据和2002年-2009年河北省138个县的谷子、小麦、玉米单产与面积数据为基础,比较分析了谷子单产的时空变化及与小麦、玉米单产的差距。结果表明,从时序上看,河北省谷子单产随着时间的变化有一定的增长趋势,但增速减缓,与小麦、玉米单产相比差距越来越大。从空间看,2002-2009年各县的谷子单产总体呈增长态势,差异比较显著。单产较高的县主要分布在山前平原和低平原区,燕山山区和坝上高原区单产较低。谷子单产水平较低的主要原因是随着时间的变化谷子由主粮作物变为了调剂粮食作物,播种区域逐步被挤压到丘陵旱地区域,农田基础设施建设薄弱,科技进步水平低、病虫草鸟危害严重等。提高谷子单产水平应加强谷子生产条件的改善,提高谷子科技水平和深加工水平,大力引导小米消费,研制适宜各类消费人群的产品。     

济宁市任城区小麦/玉米两熟区万亩保护性耕作研究示范模式研究

[目的]解决济宁市小麦/玉米两熟区传统耕作方式生产成本高,对土壤结构破坏大,土壤的生产能力降低的难题。[方法]多次试验示范和总结。[结果]构建农机农艺技术流程为"小麦联合收获(秸秆粉碎覆盖)→玉米直播→喷除草剂→田间管理(灌溉、灭虫等)→玉米收获并秸秆还田覆盖→深松(3~5年深松一次)→小麦免耕施肥播种→田间管理(灌溉、除草、灭虫等)"的适合该区保护性耕作的技术模式,通过万亩试验示范验证,该保护性耕作技术模式在确保粮食稳产增产的前提下,能够较大幅度降低生产成本。[结论]该研究可为济宁市保护性耕作技术的大面积推广奠定基础,应加快推进全市农业进入保护性耕作的新阶段。     

Algorithms for sensor-based redistribution of nitrogen fertilizer in winter wheat

Several methods were developed for the redistribution of nitrogen (N) fertilizer within fields with winter wheat (Triticum aestivum L.) based on plant and soil sensors, and topographical information. The methods were based on data from nine field experiments in nine different fields for a 3-year period. Each field was divided into 80 or more subplots fertilized with 60, 120, 180 or 240 kg N ha⁻¹. The relationships between plot yield, N application rate, sensor measurements and the interaction between N application and sensor measurements were investigated. Based on the established relations, several sensor-based methods for within-field redistribution of N were developed. It was shown that plant sensors predicted yield at harvest better than soil sensors and topographical indices. The methods based on plant sensors showed that N fertilizer should be moved from areas with low and high sensor measurements to areas with medium values. The theoretical increase in yield and N uptake, and the reduced variation in grain protein content resulting from the application of the above methods were estimated. However, the estimated increases in crop yield, N-uptake and reduced variation in grain protein content were small.     

中国粮食生产的化肥利用效率及决定因素研究

粮食生产的化肥利用效率低下是影响粮食产量进一步提高的主要障碍,不仅推升了生产成本,也是造成农业面源污染的重要原因。本文使用随机前沿生产函数,度量了我国主要粮食主产区2006-2009年三种粮食作物的化肥利用效率,并对化肥利用效率的决定因素进行了分析。研究结果表明三种作物的化肥利用效率普遍较低,分别为0.37、0.26和0.37;教育水平、收入状况、化肥价格、财政支持、种植规模等是影响化肥利用效率的重要因素。     

Analysis on water requirement and water-saving amount of wheat and corn in typical regions of the North China Plain

This paper studied the variation characters on wheat and corn water consumption and irrigation watersaving amount under different water conditions (ample irrigation level, farmers conventional irrigation level and optimizing irrigation level). The water use efficiency and water saving potential of optimizing treatment and farmers’ conventional irrigation treatment were analyzed respectively. The objective of this study was to provide theoretical supporting for popularization and application of optimizing irrigation measures. Crop water requirement under sufficient water supply was calculated by Penman equation. We obtained crop water consumption under conventional treatment and optimizing treatment by field experiment. The main results showed that the irrigation amount of wheat and corn was too much under farmers’ conventional irrigation level and basically satisfied their water requirement, therefore, the water-saving amount was smaller while water-saving potential was bigger compared with the optimizing irrigation treatment. The grain yield under optimizing irrigation treatment was improved or appreciably reduced compared with that under conventional irrigation treatment, while the water consumption and irrigation amount of optimizing irrigation treatment was lower, with a higher water use efficiency. Therefore, the optimizing irrigation treatment could achieve a stable yield and high water efficiency at the same time. Moreover, when the optimizing irrigation measure was adopted, the grain yield reached 5940 kg/hm², water-saving amount reached 91mm for winter wheat, and the grain yield reached 7743 kg/hm², with water-saving amount of 49mm for summer corn in the piedmont region of Taihang Mount. The grain yield got 7710 kg/hm², with water-saving amount of 20mm for winter wheat in Heilonggang Plain. Therefore, the water-saving amount in the piedmont region of Taihang Mountain was obviously higher than that in Heilonggang Plain. Thus, the piedmont region of Taihang Mountain in the North China Plain is viewed as the key district for water-saving.     

Optimization of corn plant population according to management zones in Southern Brazil

Precision agriculture relies on site-specific interventions determined by the spatial variability of factors driving plant growth. The main objective of this study was to assess the efficiency of variable-rate seeding of corn (Zea mays L.) with delineated management zones. This study involved two experiments carried out in Não-Me-Toque, Rio Grande do Sul, Brazil. For the first experiment, carried out in 2009/2010, management zones were delineated by the farmer’s knowledge of the crop field. The field was split into low (LZ), medium (MZ) and high (HZ) crop performance zones. In the second experiment, carried out in 2010/2011, management zones were delineated by overlaying standardized yield data from nine crop seasons (seven of soybean and two of corn). The experiment was carried out with a randomized block design with three management zones and five corn seeding rates ranging from 50 000 to 90 000 seeds per ha^?1. The soil was a Rhodic Hapludox with a subtropical climate. Optimization of the corn plant population within the field increased grain yield compared to the reference plant population (70 000 plants ha^?1). Yield increases in the LZ, due to corn plant population reduction in relation to the target population, were 1.20 and 1.90 Mg ha^?1 for first and second experiments, respectively. This resulted in economic gains of 19.8 and 28.7 %, respectively. Yield increases in the HZ were 0.89 and 0.94 Mg ha^?1, respectively, and were due to an increase in plant population in relation to the target population. This resulted in economic gains of 5.6 and 6.6 % for the first and second experiments, respectively. In the MZ, the adjustment of the target plant population was not necessary. Optimizing corn population according to management zones is a promising tool for precision agriculture in Southern Brazil.     

黑龙江省粮食生产结构演变与趋势分析

在分析黑龙江省粮食总体生产状况的基础上,以玉米、稻谷、小麦和大豆四大主要粮食作物为研究对象,从产量结构、种植面积结构和单产水平变化三个视角,揭示了黑龙江省粮食生产结构发展演变的规律和特征。这一特征表现为黑龙江省粮食生产经历了从以四种主要粮食作物为主,向以玉米和稻谷两种粮食作物为主的过渡,比较效益是玉米和稻谷在粮食生产中优势地位日益突出的主要原因,但这种生产结构不利于粮食的可持续发展。因此,未来应考虑通过建立新的耕作技术体系来进一步调整和优化粮食生产结构。     

粮食增产千亿斤：压力抑或潜力？——基于技术进步方向和关键要素的判断

中国粮食连年丰产但中央政府并没有降低对粮食安全的关注度,持续夯实粮食产能,立足自身应对需求刚性增长。文章对近年粮食生产结构调整走向,要素配置变化进行了归纳,并对粮食生产技术演变和产量潜力进行分析。结果表明,土地、水资源以及成本收益情况是粮食增产的强约束,必须依靠技术路径突破,服务规模化和经营规模化,提高生产要素边际收益。即使在技术突破时间表不确定的前提下,三大主粮特别是玉米单产增长还有较大提升空间。根据最近3次千亿斤（0.5亿t）产能增加单产增长趋势、各品种增产贡献率以及生产形势,对下一个千亿斤增产进行了3种情境预测：若水稻、小麦和玉米的年均单产增长率分别为0.7%、1.0%和0.8%,可在2026年实现7.0亿t产能,并减少约50万hm2播种面积;在水稻、小麦和玉米为0.2%、0.3%和0.4%的低增速并减少播种面积141万hm2的情境下,可在2035年提升至7.0亿t产能。当前,粮食产能稳定增长的关键在于生产（生产环节）规模化、种业攻关和农田质量建设能否取得实质性推进。     

Spatial Variability of Soil Properties, Corn Quality and Yield in Two Illinois, USA Fields: Implications for Precision Corn Management

Better understanding of within-field spatial variability of crop quality parameters and yield are needed for precision management of crops. This study was conducted to determine the magnitude of within-field variability in soil properties, corn (Zea mays L.) quality parameters and yield and to characterize their spatial structures. Another objective was to compare the effects of hybrid on corn quality, yield, and the spatial structure of grain quality. Four Pioneer hybrids were planted side-by-side, two in each of the two study fields in eastern Illinois, USA. Coefficients of variation (CV%) for soil properties varied from 6.3 (pH) to 56.8% (soil test P). All the soil properties (except pH at Site 2) displayed well-defined spatial structures, with either strong or moderate spatial dependence. Variability in corn quality and yield (CVs < 10%) was smaller than variability in soil properties. Most quality parameters examined at Site 1 exhibited either moderate or strong spatial dependence, except that corn oil (both hybrids), kernel roundness and weight (hybrid 33Y18) did not show any spatial correlation. Hybrid 33G26 had significantly higher yield and quality for most quality parameters than 33Y18 at Site 1. At Site 2, hybrid 34W67 was significantly lower in oil and protein content, length, roundness and vitreousness than 34K77, but higher in other quality parameters. Significant differences in spatial structures were also observed across hybrids for some corn quality parameters. We conclude that hybrid selection is an important strategy for precision management of corn for optimum yield and quality.     

Forecasting upcoming weather conditions of vegetation and grain-crop yield in the dry-steppe zone of the pre-Ural Region

The long-term forecast of yield and vegetation conditions of grain crops for the dry-steppe zone of the pre-Ural Region is made for the first time based on new predictors and their time lags. The forecast is developed for the value of the predictant (Y) and all predictors (X) that are included in the multiple regression models. The obtained results permit the probability of the onset of drought in the expected year to be described in advance (5–6 months before the start of field works). The developed models indicate that a strong drought is expected for grain crops in 2017 (the winter wheat yield of 2–3 c grain/ha), which is due to unfavorable weather conditions in June (the precipitation of 3–4 mm) and high air temperature in July (the average temperature in the first decade of 25.2°C and maximum temperature of 37.5°C). This information makes it possible to choose the optimal technological solutions for overcoming the influence of unfavorable conditions. The methods of step-by-step multiple regression and neural network regression and the method of residual deviations in combination with the method of superposition of epochs are used.     

Grain yield and quality of winter wheat inoculated with a mixed culture of <Emphasis Type="Italic">Pseudomonas</Emphasis> bacteria against the background of increasing nitrogen fertilizer rates

The effect of a mixed culture of non-nitrogen fixing bacterium Pseudomonas fluorescens 20 and nitrogen-fixing bacterium Pseudomonas putida 23 on winter wheat grain yield, nitrogen removal by plants, and content of protein and ash elements in grain against a background of nitrogen fertilizer was studied in a microplot experiment on gray forest soil.     

Effects of deep vertical rotary tillage on the grain yield and resource use efficiency of winter wheat in the Huang-Huai-Hai Plain of China

Tillage represents an important practice that is used to dynamically regulate soil properties,and affects the grain production process and resource use efficiency of crops.The objectives of this 3-year field study carried out in the Huang-Huai-Hai(HHH) Plain of China were to compare the effects of a new deep vertical rotary tillage (DVRT) with the conventional shallow rotary tillage (CT) on soil properties,winter wheat (Triticum aestivum L.) grain yield and water and nitrogen use efficiency at different productivity levels,and to identify a comprehensive management that optimizes both grain yield and resource use efficiency in the HHH Plain.A split-plot design was adopted in field experiments in the winter wheat growing seasons of 2016–2017 (S1),2017–2018 (S2) and 2018–2019 (S3),with DVRT (conducted once in June 2016) and CT performed in the main plots.Subplots were treated with one of four targeted productivity level treatments (SH,the super high productivity level;HH,the high productivity and high efficiency productivity level;FP,the farmer productivity level;ISP,the inherent soil productivity level).The results showed that the soil bulk density was reduced and the soil water content at the anthesis stage was increased in all three years,which were due to the significant effects of DVRT.Compared with CT,grain yields,partial factor productivity of nitrogen (PFP_N),and water use efficiency (WUE) under DVRT were increased by 22.0,14.5 and 19.0%.Path analysis and direct correlation decomposition uncovered that grain yield variation of winter wheat was mostly contributed by the spike numbers per area under different tillage modes.General line model analysis revealed that tillage mode played a significant role on grain yield,PFP_N and WUE not only as a single factor,but also along with other factors(year and productivity level) in interaction manners.In addition,PFP_N and WUE were the highest in HH under DVRT in all three growth seasons.These results provided a theoretical basis and technical support for coordinating the high yield with high resource use efficiency of winter wheat in the resource-restricted region in the HHH Plain of China.     

农作物种植结构对农民收入的影响机制研究——基于四川剑阁县57个乡镇2010-2014年的面板数据

在精准扶贫背景下,以典型贫困山区剑阁县57个乡镇2010-2014年的面板数据为基础,分析了农作物种植结构对农民收入的影响,精准地量化了5种粮食作物(小麦、水稻、玉米、番薯、大豆)和3种经济作物(油菜、花生、烤烟)对于农民收入的影响机制.结果发现,经济作物总体上要比粮食作物更能给农民收入带来正向影响,其中剑阁县应该种植水稻、大豆、油菜和烤烟4种农作物以促进农民增收.该研究对于农村因地制宜调整农作物类型、优化种植结构、发展精准农业,从而有效促进农民增收具有重要现实意义,也可为精准扶贫提供精准数据,提出一个精准化研究视角.     

山西省1989年以来粮食生产状况与对策研究

对山西省1989年以来的粮食生产情况,诸如粮食播种面积、复种指数、总产量和单位面积产量进行了调研,认为山西省粮食生产具有以下3个特征:一是粮食生产年度之间的波动性大,二是玉米成为粮食生产的主力,三是小麦和谷子的面积、单位面积产量都在下降。粮食丰产下的隐忧表现为:一是细粮供不应求,二是人均粮食占有量没有提高,三是耕地尤其是水浇地减少较多,四是农业生产成本提高。粮食生产的出路:一是政策扶持粮食生产尤其是小麦生产,二是积极发展现代农业,三是保护耕地尤其要反思退耕还林和通道绿化政策,四是重新构建与种植结构相适应的饮食结构。