有机高氮肥的施用对菠菜生长及土壤供氮能力的影响

通过盆栽试验 ,研究了有机高氮肥的施用对菠菜生长及土壤供氮能力的影响。结果表明 :与对照相比 ,2种有机高氮肥分别单施和配施 ,菠菜产量和累积吸氮量均较高 ,与单施尿素的处理相比 ,菠菜生长后期的长势更加旺盛 ,吸氮速率增加的更快 ;施用有机高氮肥能改善土壤氮素供应状况和供氮过程 ,在菠菜生长后期 (播种后 2 8～ 4 2d)为菠菜提供了充足的矿质氮 ;播种 14d后 ,有机高氮肥的施用能明显增加土壤微生物量氮 ,增加幅度大于单施尿素处理 ,因此提高了土壤的供氮能力。上述结果表明 ,施用有机高氮肥有可能获得与施用化肥相当的产量 ,这为生产有机食品专用肥料提供了技术途径。

高密度高氮肥对大麦白粉病抗病性及产量性状的影响

以南方大麦区试品系为材料,研究高密度、高氮肥水平对大麦白粉病抗病性及产量性状的影响。结果表明:高密度、高氮肥使白粉病严重度和病情指数极显著升高,对总病叶率影响不大;千粒重、穗长、产量及株穗重显著或极显著降低,株高极显著升高,而穗数、结实率不因密度、氮肥增加发生明显变化。在高密度、高氮肥条件下不同品系的抗病性存在较大差异,分为两种反应:一种对白粉病抗性基本无影响,另一种对白粉病抗性反应较敏感。

高产高蛋白高氮肥效率春小麦品种的硝酸还原酶活性的研究

采用田间试验 ,在不同供氮条件下 ,研究了高产高蛋白高氮肥效率春小麦品种的硝酸还原酶活性 ,结果表明高产高蛋白高氮肥效率春小麦品种的硝酸还原酶活性 (NRA)较高 ,生育后期NRA下降较慢 ,高NRA的持续时间较长。相关分析表明 ,NRA与小麦籽粒产量和蛋白质产量、蛋白质含量都有显著的正相关关系。因此 ,NRA可作为作物高产高蛋白含量与高氮肥效率的一个很好的生理指标 ,选择关键生育期的NRA作为选育小麦高产高蛋白含量与高氮肥效率品种指标 ,对科学的选育小麦优良品种有重要的参考价值。

高氮肥对寒地水稻产量和群体形态的影响

为给寒地水稻的生产提供技术方案,通过不同高氮肥水平试验,研究了寒地水稻在产量及群体形态上的变化。结果表明:尿素施用量为362.5kg.hm-2时,龙粳18和龙粳20产量达到了最大值(11 407.41和9 710.24kg.hm-2),尿素施用量400kg.hm-2时龙粳14产量达到9 246.19kg.hm-2,并且各个处理小区增产效果明显;增施氮肥对穗长和剑叶的长度无显著影响,随着施氮量的增加,平均穗粒数具有显著增加趋势,而在最高的氮肥应用量上结实率显著降低。

尿基高氮肥生产工艺的影响因素

介绍了尿基高氮肥生产过程中出现的问题,分析了造粒温度、料浆温度、干燥温度以及造粒物料含水量和干燥物料含水量对尿基高氮肥生产的影响。通过合理调节温度和物料含水量,保证了装置的连续稳定运行,减轻了设备的结疤程度并降低了故障率,提高了装置的开车率。

低密高氮条件下留叶枝对棉花产量和养分吸收的影响

以冀668为试验品种,研究低密度和高施氮量条件下留叶枝对棉花产量和养分吸收的影响。结果表明:密度、施氮量和叶枝去留对棉花产量的影响达到显著或极显著水平。在18 000株·hm-2、施氮量450kg·hm-2条件下,留叶枝处理的产量显著高于去叶枝处理;在18 000株·hm-2、施氮量525kg·hm-2条件下,留叶枝处理的产量略低于去叶枝处理。在22 500株·hm-2密度条件下,2种施氮水平下留叶枝处理和去叶枝处理产量之间的差异均不显著。在18 000株·hm-2、施氮量450kg·hm-2、留叶枝条件下,棉株干物质积累、分配和氮、磷、钾吸收较为合理,产量最高,达到4 680.00kg·hm-2。在22 500株·hm-2、施氮量525kg·hm-2条件下,植株生殖器官干重虽较高,但出现了贪青迟熟现象,后期棉铃无法正常吐絮,产量较低。

高氮条件下不同水稻品种抗病差异研究

对高氮条件下不同水稻品种稻瘟病与纹枯病的发病情况及对产量性状的影响进行了分析。结果表明,高氮处理稻瘟病和纹枯病的病情指数和发病率均高于对照,且差异明显,说明高氮条件有利于稻瘟病和纹枯病的发生;高氮处理大多数品种齐穗期晚于低氮处理,高氮处理平均株高高于低氮处理,但高氮处理平均有效穗数及千粒重均低于低氮处理,平均单株总重二者无差异。

谷子穗期一喷多效防病虫增产增效用药组合防控效果对比分析

为了提高中后期谷子一喷多效防控效果,延缓中后期谷子早衰,促大穗、增粒重,促进谷子提质增效。景县在2023年开展了磷酸二氢钾、5%氨基寡糖素、芸苔素内酯、益施帮(生物激活剂)、矿源缓释高氮肥(腐殖酸水溶肥料)对比试验示范。对微肥或生产调节剂进行筛选,找出对谷子防病虫和增产效果显著的药剂组合,为谷子产业健康发展提供技术支撑。

Effects of Postponing N Application on Metabolism,Absorption and Utilization of Nitrogen of Summer Maize in SuperHigh Yield Region

[Objective] The aim was to explore effects of application postponing of N fertilizer and the mechanism of yield increase in order to provide references for N fertilizer application in a rational way. [Method] In a super-high yielded region of summer maize, field experiment was conducted to research effects of N fertilizer postponing on key enzymes of N metabolism, yield of maize and N fertilizer use. [Result] After application of N fertilizer was postponed, NR, SPS and GS activities of ear-leaf of summer maize increased by 11.99%-34.87%, 8.25%-10.64% and 10.00%- 16.81% on the 28^th d of silking; content of soluble sugar in leaves enhanced signifi- cantly and accumulated nitrogen increased by 5.00%-9.74% in mature stage. The postponing fertilization of ＂30% of fertilizer in seedling stage＋30% of fertilizer in flare- opening stage＋40% of fertilizer in silking stage meets N demands of summer maize in late growth period. Compared with conventional fertilization, the maize yield, agro- nomic efficiency and use of N fertilizer all improved by 5.05%, 1.75 kg/kg and 6.87%, respectively, after application postponed. [Conclusion] Application postponing of N fertilizer maintains activity of NR, GS and SPS higher and coordinates metabolism of C and N in late growth period, to further improve yield of maize.

Effects of Nitrogen Level and High Temperature Stress on Yield, SPAD Value and Soluble Sugar Content of Early Rice Ganxin 203

This study aimed to investigate the combined effects of nitrogen level （high and ordinary） and high temperature stress （37 ℃, 4 d） at the late panicle ini- tiation stage on yield, SPAD value and soluble sugar content of Ganxin 203, an early rice cultivar. The results showed that under both high and ordinary nitrogen levels, high temperature stress reduced the seed-setting rate, yield per stem, SPAD value and soluble sugar content of Ganxin 203; under both high and ordinary tem- peratures, high nitrogen level increased the seed-setting rate, yield per stem and soluble sugar content of Ganxin 203; the seed-setting rate, yield per stem and yield per plant of Ganxin 203 under high temperature and high nitrogen level were higher than those under high temperature and ordinary nitrogen level. It suggests that ap- propriate high nitrogen level contributes to weakening the negative effects of high temperature stress on rice yield.

Effect of N Fertilization on Yield, N Absorption and Utilization of Two Species of Super High-Yielding Summer Maize

[Objective] The aim was to study on effects of N fertilizer on yield, N absorption and utilization of different cultivars of super high-yielding summer maize, in order to provide reference for reasonable N fertilization in accordance with different cultivars. [Method] Field experiment was conducted to study on effects of different N fertilizers on yield, N absorption and use efficiency of Zhengdan 958 and Xundan 20, in order to learn the effect differences at different N fertilizer levels. [Result] After N was applied, yields of the two summer maize increased significantly. Zhengdan 958 achieved the highest in yield and proceeds at 12 051.18 kg/hm2 and 1 722.40 yuan/hm2, respectively in low N level. In contrast, Xundan 20 achieved the highest at 13 166.00 kg/hm2 and 1 343.92 yuan/hm2 in the above two aspects in high N level. Compared with Zhengdan 958, Xundan 20 increased by 9.90%, 5.20% and 12.00% in N levels of 0, 240, and 450 kg/hm2, respectively. When N fertilizers were applied, protein yield of Xundan 20 was significantly higher than that of Zhengdan 958, so that higher N fertilizers contributed higher protein yield for Xundan 20. In high N level, N efficiency, N-fertilizer utilization and partial productivity of Xundan 20 were significantly higher than that of Zhengdan 958. [Conclusion] Lower N-fertilizer was suitable for Zhengdan 958 and Xundan 20 would get a good harvest if more N-fertilizers were applied. The results provided references for reasonable N fertilization.

尿基复合肥生产类型和造粒影响因素

尿基复合肥品种很多,生产过程中各种造粒各具特点。介绍了尿基复合肥(尿基高氮型、尿基均衡型、尿基氮钾肥、尿基高钾型)的特点及造粒过程的影响因素(物料温度、物料湿度、液固比、管式反应器N/P),提出在尿基复合肥生产过程中,应根据各种造粒特点,做出有针对性的调节,及时准确地把握各种尿基复合肥的造粒特点,使生产处于稳定的高产状态,从而降低生产能耗,提高产品质量,减少设备故障,保证设备稳定运行。

Effects of Soil Nitrate Nitrogen Residues and Leaching for Different Kinds of Slow-release Nitrogen Fertilizers in Tall-fescue Soil

ObjectiveThe aim was to explore the movement of nitrate nitrogen in tall-fescue soils by different kinds of slow release nitrogen fertilizers. MethodBased on infiltration-tanks and test plots, a new and environment friendly fertilizer was explored. ResultThe results show that compared with urea treatment, slow-release nitrogen fertilizer treatments could reduce nitrate nitrogen content and leaching amount in soils. Compared with PCU30 and IU treatments, the PCU60 treatment became more efficient in reducing nitrate content and leaching amount in 0-90 cm soil layer. ConclusionIn summary, slow-release nitrogen fertilizer, which can reduce soil nitrate content and leaching losses, is a kind of novel fertilizer with high environmental benefit and promising application.

The Effects of Manure, Lime and P Fertilizer on N Uptake and Yields of Soybean （Glycine max （L.） Merrill） in the Central Highlands of Kenya

Soybean （Glycine max （L.）） is one of the most important legume crops being introduced in the CHK （Central Highlands of Kenya） expected to increase yields. However, low levels of soil N （nitrogen） and other plant nutrients and soil acidity are seen as the major causes impairing goal achievement. To evaluate the influence of manure, lime, P （phosphorus） fertilizer and their combination on N uptake and soybean performance, an experiment was conducted in Embu ATC （Agricultural Training College） comprising 9 treatments, arranged in a Randomized Complete Block Design with 4 replicates in plots of 4 m×4.5 m. The study included manure （0, 5 and 10 t-ha-1）, lime （0 and 2 t.ha-1） and P fertilizer （0, 30 and 60 kg.P.hal）. The treatments significantly influenced N uptake and soybean yields. Both parameters responded well to application of manure both alone or combined to lime and TSP （triple super phosphate）. From these it was concluded that organic and inorganic resources have potential to enhance N uptake and soybean and other crops yields in CHK.

Effect of Combined Use of Brackish Water and Nitrogen Fertilizer on Biomass and Sugar Yield of Sweet Sorghum

Soil salinization and non-point source pollution are among the most important and widespread environmental problems in European Mediterranean regions. Sweet sorghum （Sorghum bicolor （L.） Moench var. saccharatum） is a moderate to high salinity tolerant crop with low water and nutrient needs, seen as an alternative to grow in the water scarce regions. A three-year multifactorial study was conducted in southern Portugal to evaluate the combined effects of saline water and nitrogen application on the dry biomass （total, stems, and leaves）, sugar content （total reducing sugars and sucrose eontents） and sugar yield （here defined as the product of total reducing sugars and stems dry biomass） functions of sweet sorghum. Sorghum dry biomass and sugar yield showed diminishing returns for each incremental change of nitrogen. The use of saline irrigation waters also led to yield reduction. Exception was sucrose content which increased with increasing levels of sodium in the soil. Nitrogen need decreased as the amount of sodium applied increased. Stem dry biomass, sucrose content, and sugar yield progressively increased with progress in the experiment. The effect could be attributed to the increase of the amount of irrigation applied throughout the years, thus increasing the leaching fraction which promoted salt leaching from the root zone, reduced the salinity stress, increased plant transpiration, nitrogen uptake and biomass yield.

Effects of Nitrogen and Phosphorus Fertilization on Soil pH-Plant Productivity Relationships in Upland Grasslands of Northern Greece

The potential role of soil pH in modulating plant productivity was assessed on the basis of dry mass, harvested in the form of 0.25 m2 quadrats, in two low-productivity upland grasslands of northern Greece subjected to annual factorial nitrogen （N） and phosphorus （P） fertilization （15 g N m-2 year-1 and 10 g P m-2 year-I） over a minimum period of 3 years. It was hypothesized that under these particular conditions, a positive relationship would exist between soil pH and plant productivity and, further, that N or P fertilizer application of a nutrient limited system, would result in a weakening of this positive relationship. A significant positive relationship was confirmed between soil pH and plant productivity in one of the two study areas and a positive trend in the other. Moreover, plant productivity increase, following fertilization, appeared to have a detrimental effect on the soil pH-plant productivity relationship. Findings support the original hypotheses and strengthen the idea that plant diversity-mediated soil pH-plant productivity relationships are a result of the more intense plant speciation that occurred under the more ＂typical＂ soil conditions of higher pH in temperate as opposed to tropical regions