Assessing the effects of urea and nano-nitrogen chelate fertilizers on sugarcane yield and dynamic of nitrate in soil

ABSTRACT

The aim of this study was to evaluate the effect of urea and Nano-Nitrogen Chelate (NNC) fertilizers on yield of sugarcane (Saccharum Officinarum) and nitrate leaching from soil. The treatments included urea (U) and NNC at five levels of nitrogen (0, 80, 112, 137 and 161 kg N ha^?1). This experiment was carried out during 2017 and 2018 in Khuzestan province, Iran. The results showed that the average of soil nitrate concentration during the sugarcane growth period in urea and NNC treatments were 10.2 and 12.8 mg kg^?1 respectively. The highest and lowest nitrate leaching (699.0 mg l^?1 and 183.0 mg l^?1) belongs to the highest level of urea fertilizer and the lowest level of NNC. In urea treatments, the lowest amount of nitrate was observed in the topsoil (0-30 cm depth) whereas in NNC fertilizer maximum value was achieved in topsoil. The height of sugarcane stem in both fertilizers increased with increasing rate of fertilizer, but there was no significant difference between two types of fertilizer. Yield of sugarcane (fresh weight of stem) increased significantly by increasing of fertilizer application, but there was no significant difference between two types of fertilizer. In terms of sugar content, there was a significant difference between treatments. The order of nitrogen use efficiency (NUE) for stems and sugar yield from high to low was as NUE (fresh stem): U₁ > N₁ > N₃ ≥ U₃ ~ U₂ > N₄ ~ U₄ > N₂ and for NUE (sugar): N₁ > U₁ > N₃ ≥ N₂ > U₂ ~ N₄ ≥ U₃ > U₄. This study showed that application of nano nitrogen fertilizer (NNC) had significant effects on reducing nitrate leaching and increasing sugar production in sugarcane. However, when nitrate leaching and its effects on human health and the environment are in view, nano fertilizers are valuable.     

氮高效组合协优9019的氮肥运筹规律与效益分析

[目的]探讨施氮时期和施氮量对协优9019的氮肥利用率、产量及效益的影响。[方法]设施化学氮素时期和施氮量8种处理,采用L8（4×24）正交设计,以不施化学氮素为对照,进行施氮时期和施氮量对协优9019的氮肥利用率、产量及效益的影响试验。[结果]协优9019的适宜施氮量在172.5~243.45 kg/hm2,以施纯氮172.5 kg/hm2的处理增产较高,增收效益最明显,氮肥利用效果最好。在施172.5kg/hm2纯氮的合理运筹下,其氮素农学利用率为25 kg/kg氮素,每生产100 kg稻谷只需施纯氮1.76 kg,比对照增加产值7762.5元/hm2,每千克纯氮增收45.00元,单位面积增收7012元/hm2,增效相当可观。[结论]协优9019氮肥合理施肥模式应是：基蘖肥各施纯氮69.0kg/hm2,保花和齐穗期各施纯氮34.5 kg/hm2。再次验证协优9019是氮高效杂交组合。     

Comparison of Five Nitrogen Dressing Methods to Optimize Rice Growth

Abstract

The applicability of five nitrogen (N) dressing methods to rice cultivation was examined using the canopy spectrum-based nitrogen optimization algorithm (CSNOA), leaf area index (LAI), site-specific N management (SSNM), N nutrition index (NNI), and N fertilizer optimization algorithm (NFOA). After base-tiller N dressing (basal dressing and top dressing at the tillering stage) at low and normal levels, rice plants were grown by the above five N dressing methods. The effects of different N dressing methods on plant dry weight, plant N accumulation, grain yield, N use efficiency, and economic benefit were analyzed. Compared with the standard method, under the low base-tiller N dressing level, the optimum N dressing rate was decreased, and the economic benefit was increased by adapting the N dressing methods of CSNOA and SSNM, whereas the optimum N dressing rate was increased, and the economic benefit was decreased by the other three N dressing methods. Under the general base-tiller N dressing level, the optimum N rate, N-use efficiency and economic benefit were increased by all N dressing methods except the NFOA. These results indicated that the CSNOA and SSNM were two good techniques for quantifying N dressing in rice, with higher economic benefit, less N input, and better applicability under different base-tiller N dressing levels.     

盆栽条件下不同氮素利用效率油菜农艺性状的差异

油菜盆栽试验表明,在氮素供应水平较高时,氮高效基因型籽粒产量、籽粒占总生物量的比例和每角粒数均高于氮低效基因型,而茎叶生物量、茎叶占总生物量的比例则显著低于氮低效基因型。油菜氮素利用效率与籽粒产量、籽粒产量占总生物量的比例和每角粒数呈正相关,与营养生长阶段和成熟期地上部分生物量、成熟期茎叶生物量、根系生物量、根冠比、总生物量、茎叶生物量占总生物量的比例和根系生物量占总生物量的比例均呈显著或极显著的负相关。在施氮水平较低的情况下,氮高效基因型籽粒产量、籽粒占总生物量的比例、每角粒数、第一个有效分枝高度和单株有效角果数均显著高于氮低效基因型,而茎叶占总生物量的比例则显著低于氮低效基因型。氮素利用效率与籽粒产量、籽粒产量占总生物量的比例、每角粒数、第一个有效分枝高度和单株有效角果数有显著或极显著正相关关系,而与茎叶占总生物量的比例呈极显著负相关关系。氮低效基因型干物质分配比例对供氮水平比氮高效基因型更敏感。     

Effect of time of application on nitrogen uptake,partitioning, and remobilization in walnut trees

Walnut tree requires a relatively high amount of nitrogen (N). To avoid loss in the environment, N uptake efficiency (NUE) should be optimized. The aims of this study were to evaluate the effect of time of N application on NUE, partitioning, and remobilization in walnut trees. Two-year-old trees were planted in 40-L pots and fertilized with 1 g of ¹⁵N-enriched (5 atom %) N at: 1) bud burst, 2) pistillate flower maturity, and 3) late summer. One week after fertilization, the percentage of N derived from fertilizer and NUE were higher in trees fertilized in late summer, than other timings. N uptake was linearly related to root dry weight. At May 2008 harvest, the N stored in trunk and twigs was remobilized to the developing leaves and to the roots. Late summer N application appeared to be the most effective in providing N for walnut spring new growth.     

The yields,agronomic, and nitrogen use efficiency traits of wheat cultivars in north China under N-sufficient and -deficient conditions

In this study, the yields, yield components, agronomic, and nitrogen use efficiency (NUE) traits of the eighty-four winter wheat cultivars were investigated under nitrogen (N)-sufficient and -deficient conditions. Dramatic variations were observed in the yield and agronomic traits among the cultivars. Based on absolute yields under the N treatments, the cultivars were categorized into N efficiency groups of high, close high, medium, and low, in which the high efficiency group cultivars generally exhibited improved agronomic traits under these contrasting N-supply conditions. Additionally, the wheat cultivars were classified into various N response groups, including toleration, relative toleration, sensitive, and most sensitive based on the ratios of yield under N deficiency to that under N sufficiency. Regression correlation analyses revealed that straw biomass, total biomass, grain N amount, and straw N amount were significantly correlated with yield, suggesting that these traits can be acted as indices in evaluating yield potentials in wheat.     

Natural variation of Arabidopsis thaliana root architecture in response to nitrate availability

Root system architecture (RSA) plays a crucial role in nutrient and water uptake in plants. RSA can be modulated to improve nitrogen use efficiency (NUE) of crops, decreasing the need for fertilization. In this study, we analyzed 12 root parameters in 48 Arabidopsis accessions grown in media with low or high nitrogen (N). Low N repressed six root traits and enhanced six others. A principal component analysis showed that six components contributed to 90.08% of N availability. The primary component contributed to 35.64% of the variation and was associated with LR characteristics. The 48 Arabidopsis accessions were divided into five response groups. Stw-0 had the highest biomass production and a high N concentration in both roots and shoots, independent of growth conditions. H55 had numerous LRs at low N. Our results provide N-responsive parameters suitable for mapping of quantitative trait loci related with root morphology.     

Application of Optimum N Through Different Fertilizers Alleviate NH4+-N,NO3–N and Total Nitrogen Losses in the Surface Runoff and Leached Water and Improve Nitrogen Use Efficiency of Rice Crop in Erhai Lake Basin,China

Non-point source pollution from the Agri-sector (especially nitrogen (N)) due to the application of conventional urea with heavy rates not only depleted the water quality of Erhai Lake but also declined the nitrogen use efficiency (NUE) of different crops grown in the Erhai Lake Basin, Dali, Yunnan, China. It is imperative to mitigate the total nitrogen and its forms (nitrate (NO₃^?)-N and ammonium (NH₄⁺)-N) loading to the surface and subsurface water flow through optimum fertilizer management for crop production in the region. To achieve this goal, a balanced crop nutrition system was practiced with different fertilizer types for rice-broad bean crop rotation system. The crop nutrition system consisted of No Fertilizers (CK), Conventional Fertilizer Practice (CF), Conventional urea as environmental Fertilizer (T₁), Refined Organic Fertilizer applied solely (T₂), Refined Organic Fertilizer applied with conventional urea (T₃), Refined Organic Fertilizer applied in T₂ was increased 4 times (T₄), Refined Organic Fertilizer applied in T₃ was increased 4 times but the same amount of conventional urea (T₅), and Controlled Release Fertilizer (CRF) application (T₆). The same rate of nitrogen (20% lower than CF) was applied in T₁, T₂, T₃, and T₆. All the former mentioned treatments were compared to CF with respect to different variables. In case of crop production, T₆ gave maximum rice grain yield (9.9 t ha^?1) and broad bean yield (5.1 t ha^?1). Treatments T₁ and T₅ were at par for rice grain yield (7.8 t ha^?1) and this quantity was not significantly lower than CF. Treatments T₆, T₅, and T₁ were observed 29%, 47%, and 46%, respectively lower in TN loading to the surface and percolating water than the CF. Conventional urea and refined organic fertilizer combined with conventional urea at reduced nitrogen rates can be a reliable option for crop production in the Erhai Lake Basin with optimum yield under the rice-broad bean crop rotation system. CRF at reduced nitrogen rate can be a better option for higher yield and lower NO₃^–N, NH₄⁺-N and total nitrogen losses to the surface runoff and leached water.     

施用控释BB肥对冬小麦产量、氮素累积和氮肥利用率的影响

2013年10月-2014年6月在河南省商丘市民权县布置田间小区试验,研究施用控释BB肥对冬小麦产量及其构成要素、植株各部位对氮素吸收与累积及氮肥利用率的影响。结果表明,施用控释BB肥在所有处理中效果最佳,较农民习惯施肥在穗粒数、理论产量、实际产量、生物产量及收获指数等指标上分别增加20.61%、27.08%、8.41%、5.87%、4.44%;在籽粒氮质量分数、氮素累积量上分别增加24.81%、28.47%;在氮肥利用效率、氮肥贡献率上较农民习惯施肥分别增加89.56%、15.24%。施用控释BB肥在减氮20%的条件下,较农民习惯施肥和普通BB肥在冬小麦产量上没有显著的影响,但提高植株各部位对氮素的吸收及累积作用,同时明显提高氮肥的利用效率。说明,施用控释BB肥可以明显提高冬小麦产量及其构成要素,增加植株对氮素的吸收及累积量,提高氮肥利用率。     

番茄氮肥利用效率的基因型差异研究

为明确番茄的氮肥利用特性,从而为因种施肥和提高氮肥利用效率提供依据。以吉林省市场上常见的25个番茄品种为试材,对其氮肥吸收利用率(RE)、氮肥生理利用率(PE)、氮肥农学利用率(AE)和氮肥偏生产力(PFP)的差异进行比较。结果表明,不同番茄品种的RE、PE、AE、PFP均存在显著差异。聚类分析显示,产量和氮肥利用效率(NUE)较高的番茄品种有朝研219、佳粉19、倍盈、赛欧1号和瑞琦1号。相关分析表明,提高氮收获指数,有利于产量和NUE的提高。