Combined Application Of Nitrogen Research Articles

Nitrogen fertilization and soil nitrogen cycling: Unraveling the links among multiple environmental factors, functional genes, and transformation rates

Anthropogenic nitrogen (N) inputs substantially influence the N cycle in agricultural ecosystems. However, the potential links among various environmental factors, nitrogen functional genes, and transformation rates under N fertilization remain poorly understood. Here, we conducted a five-year field experiment and collected 54 soil samples from three 0–4 m boreholes across different treatments: control, N-addition (nitrogen fertilizer) and NPK-addition (combined application of nitrogen, phosphorus and potassium fertilizers) treatments. Our results revealed pronounced variations in soil physiochemical parameters, metal concentrations and antibiotic levels under both N and NPK treatments. These alternations induced significant shifts in bacterial and fungal communities, altered NFG abundance and composition, and greatly enhanced rates of nitrate reduction processes. Notably, nutrients, antibiotics and bacteria exerted a more pronounced influence on NFGs and nitrate reduction under N treatment, whereas nutrients, metals, bacteria and fungi had a significant impact under NPK treatment. Furthermore, we established multidimensional correlations between nitrate reduction gene profiles and the activity rates under N and NPK treatments, contrasting with the absence of significant relationships in the control treatment. These findings shed light on the intricate relationships between microbial genetics and ecosystem functions in agricultural ecosystem, which is of significance for predicting and managing metabolic processes effectively.

Optimizing rice yield, quality and nutrient use efficiency through combined application of nitrogen and potassium.

Reasonable nitrogen (N) and potassium (K) application rates can effectively improve fertilizer use efficiency, rice yield and quality. A two-year field experiment was conducted with combined application of three N rates (135, 180, and 225 kg ha-1, denoted as N1-N3) and four K rates (0, 90, 135, and 180 kg ha-1, denoted as K0-K3) using super indica hybrid rice cultivar Yixiangyou (YXY) 2115 to explore the effects of co-application of N and K on rice growth and development. The results indicated that the combined application of N and K had significantly interactive effects on dry matter (DM) accumulation, nutrients absorption, N harvest index (NHI), K harvest index (KHI), spikelets per panicle and most rice quality indexes. The highest total DM accumulation (17998.17-19432.47 kg ha-1) at maturity stage was obtained under N3K2. The effect of co-application of N and K on nutrients absorption and utilization varied between the two years and within each year. The highest total N and K accumulations at maturity stage were observed under N3K1 and N3K2, respectively, while the highest N recovery efficiency (NRE) and K recovery efficiency (KRE) were observed under N1K3. High expression levels of N and K metabolism-related genes in rice grains were observed under N3K2 or N3K3, consistent with N and K uptake. Co-application of N and K increased rice yield significantly and the highest yield (6745.02-7010.27 kg ha-1) was obtained under N2K2. As more N was gradually applied, rice appearance quality improved but milling, cooking and eating quality decreased. Although appropriate application of K could improve rice milling, cooking and eating quality, it reduced appearance quality. The optimal milling, cooking and eating quality were obtained under N1K2, while the best appearance quality was obtained under N3K0. Overall, a combination of 135-210 kg ha-1 N and 115-137 kg ha-1 K application rates was recommended for achieving relatively higher yield and better quality in rice production.

Combined Application of Nitrogen and Phosphorus Promotes the Growth and Nutrient Accumulations of Cinnamomum camphora Container Seedlings

Combining the application of nitrogen and phosphorus is widely recognized as an effective measure to promote seedling growth. The purpose of this study was to investigate the effects of the combined application of nitrogen and phosphorus on the growth and nutrient status of C. camphora container seedlings. Exponential fertilization was applied to a range of fertilizers, including single nitrogen fertilizer, single phosphorus fertilizer, and combinations of nitrogen and phosphorus to C. camphora. Eight distinct fertilization levels of treatment (CK, N1, N2, N3, P, N1P, N2P, and N3P) were established. The height and ground diameter of the seedlings were determined periodically in each treatment group. Biomass, root system (including root length, root surface area, and root volume), and nutrient accumulation (content of soluble sugars, soluble proteins, and starch in the root system, stems, and leaves) were determined for each treatment group of seedlings. The N3P treatment (N: 9000 mg∙plant−1 + P: 6000 mg∙plant−1) had the most significant effect on the height and ground diameter of C. camphora container seedlings, while the N3 treatment (N: 9000 mg∙plant−1) proved to be the most beneficial for biomass accumulation among the eight different fertilizer levels. In addition, a single P fertilizer (P: 6000 mg∙plant−1) emerged as the most effective fertilizer for enhancing root morphology (root length, root surface area, root volume, and root average diameter) and accumulating nutrient composition (soluble sugar, soluble protein, and starch). Furthermore, it was discovered that a high level of nitrogen fertilization hindered the accumulation of nutrient composition in C. camphora container seedlings. Our comprehensive analysis revealed that nitrogen fertilizer promoted the morphological growth of C. camphora container seedlings, while phosphorus fertilizer proved to be the most beneficial for root growth and nutrient composition accumulation. Additionally, it was emphasized that controlling the quantity of nitrogen fertilizer is also a crucial measure.

Appropriately Reduced Nitrogen and Increased Phosphorus in Ratooning Rice Increased the Yield and Reduced the Greenhouse Gas Emissions in Southeast China

Reducing greenhouse gas emissions while improving productivity is the core of sustainable agriculture development. In recent years, rice ratooning has developed rapidly in China and other Asian countries, becoming an effective measure to increase rice production and reduce greenhouse gas emissions in these regions. However, the lower yield of ratooning rice caused by the application of a single nitrogen fertilizer in the ratooning season has become one of the main reasons limiting the further development of rice ratooning. The combined application of nitrogen and phosphorus plays a crucial role in increasing crop yield and reducing greenhouse gas emissions. The effects of combined nitrogen and phosphorus application on ratooning rice remain unclear. Therefore, this paper aimed to investigate the effect of combined nitrogen and phosphorus application on ratooning rice. Two hybrid rice varieties, ‘Luyou 1831’ and ‘Yongyou 1540’, were used as experimental materials. A control treatment of nitrogen-only fertilization (187.50 kg·ha−1 N) was set, and six treatments were established by reducing nitrogen fertilizer by 10% (N1) and 20% (N2), and applying three levels of phosphorus fertilizer: N1P1 (168.75 kg·ha−1 N; 13.50 kg·ha−1 P), N1P2 (168.75 kg·ha−1 N; 27.00 kg·ha−1 P), N1P3 (168.75 kg·ha−1 N; 40.50 kg·ha−1 P), N2P1 (150.00 kg·ha−1 N; 13.50 kg·ha−1 P), N2P2 (150.00 kg·ha−1 N; 27.00 kg·ha−1 P), and N2P3 (150.00 kg·ha−1 N; 40.50 kg·ha−1 P). The effects of reduced nitrogen and increased phosphorus treatments in ratooning rice on the yield, the greenhouse gas emissions, and the community structure of rhizosphere soil microbes were examined. The results showed that the yield of ratooning rice in different treatments followed the sequence N1P2 > N1P1 > N1P3 > N2P3 > N2P2 > N2P1 > N. Specifically, under the N1P2 treatment, the average two-year yields of ‘Luyou 1831’ and ‘Yongyou 1540’ reached 8520.55 kg·ha−1 and 9184.90 kg·ha−1, respectively, representing increases of 74.30% and 25.79% compared to the N treatment. Different nitrogen and phosphorus application combinations also reduced methane emissions during the ratooning season. Appropriately combined nitrogen and phosphorus application reduced the relative contribution of stochastic processes in microbial community assembly, broadened the niche breadth of microbial communities, enhanced the abundance of functional genes related to methane-oxidizing bacteria and soil ammonia-oxidizing bacteria in the rhizosphere, and decreased the abundance of functional genes related to methanogenic and denitrifying bacteria, thereby reducing greenhouse gas emissions in the ratooning season. The carbon footprint of ratooning rice for ‘Luyou 1831’ and ‘Yongyou 1540’ decreased by 25.82% and 38.99%, respectively, under the N1P2 treatment compared to the N treatment. This study offered a new fertilization pattern for the green sustainable development of rice ratooning.

Nitrogen and Phosphorus Counteracted the Adverse Effects of Salt on Sorghum by Improving ROS Scavenging and Osmotic Regulation

Fertilizer management is one of the easiest and most practical ways of combating salt stress. This study was done to evaluate the alleviative effects of nitrogen and phosphorus on the growth and salt tolerance of salt-affected sorghum. A controlled study organized in a randomized block design with three replications was conducted, testing three nitrogen rates (N0: 0 kg ha−1, N1: 180 kg ha−1, N2: 360 N kg ha−1) and phosphorus rates (P0: 0 P2O5 kg ha−1, P1: 60 P2O5 kg ha−1, P2: 120 P2O5 kg ha−1). Nitrogen and phosphorus application had positive effects on morphological indexes (plant height, stem diameter), some physiological and biochemical attributes (the content of proline and soluble protein, and the activities of superoxide dismutase, catalase, peroxidase, and ascorbate peroxidase), and aerial biomass (fresh and dry weight) of sorghum grown in saline soils. Reactive oxygen species accumulation and cell membrane damage were decreased with the application of nitrogen and phosphorus. Compared with sole fertilizer, the combined application of nitrogen and phosphorus showed better performance in alleviating salt damage on sorghum. Despite the fact that the maximum of most of the measured parameters and the minimum of reactive oxygen species accumulation and cell membrane damage were generally obtained at N1P1 and N2P2 treatment, N1P1 was recommended to be the suitable treatment considering economic benefits and environmental protection.

Chlorophyll Meter: A Precision Agricultural Decision-Making Tool for Nutrient Supply in Durum Wheat (Triticum turgidum L.) Cultivation under Drought Conditions

How crop biodiversity adapts to drought conditions and enhances grain yield became the most important issue facing agronomists and plant breeders at the turn of the century. Variations in genetic response, inadequacy of nutrients in the soil, and insufficient access to nutrients are factors that aggravate drought stressors. The development of screening tools for identifying drought tolerance is important in the deployment of durum wheat varieties suited to drought-prone environments. An experiment was conducted to evaluate durum wheat varieties under a range of nutrient supplies in naturally imposed drought conditions. The treatments consisting of two nitrogen regimes (i.e., control and 60 kg ha-1), four durum wheat varieties, and three types of nutrients (control, sulfur, and zinc) that were arranged in a split-split plot design with three replications. Both foliar-based sulfur and zinc fertilization were employed at the flag leaf stage, at a rate of 4 and 3-L ha-1, respectively. The results showed a significant (p < 0.05) genetic variation in chlorophyll concentration, grain protein content, tillering potential, and leaf area index. Varieties that contained better leaf chlorophyll content had improved grain yield by about 8.33% under 60 kg/ha nitrogen. A combined application of nitrogen and zinc at flag leaf stage significantly improved grain yield of Duragold by about 21.3%. Leaf chlorophyll content was found to be a more important trait than spikes per m2 to discriminate durum wheat varieties. Foliar application of sulfur increased the grain yield of drought-stressed plants by about 12.23%. Grain yield and protein content were strongly correlated with late-season SPAD readings. Significant (p < 0.05) correlation coefficients were obtained between normalized difference vegetation index, leaf area index, grain yield, and protein content with late-season chlorophyll content, revealing the importance of chlorophyll content in studying and identifying drought-tolerant varieties.

Эффективность возделывания гороха Премьер в зависимости от вносимых минеральных удобрений и норм посева

Purpose: to study the efficiency of cultivation of the variety Premier peas on ordinary chernozem, depending on mineral fertilizers and seed sowing rates. Materials and methods. The experience was laid on the fields of the Department of Agriculture and Crop Production of Federal Rostov Agricultural Research Centre. The objects of research are the elements of pea productivity, yield and protein content in grain, depending on the fertilizers applied and the seeding rate. Statistical analysis of data, records and observations were carried out according to the method of B. A. Dospekhov. Results. The sowing rate influences the el-ements of pea productivity. An increase in the rate to 1.2 million seeds/ha leads to a signifi-cant reduction in the number of formed beans, the number of seeds in a bean, and a decrease in grain weight. Fertilizers did not have a significant effect on the elements of productivity. The introduction of phosphorus and potash fertilizers leads to a significant increase in the yield of peas. The combined application of nitrogen, phosphorus and potassium leads to a sig-nificant increase in yield when sown 1.0 and 1.2 million seeds/ha. Nitrogen fertilizers do not have a significant impact on the yield of peas. The fertilizers application helps to increase the protein content in the grain. The maximum was obtained in the N₆₀ variant, amounting to 24.8 %. The responsiveness of peas to introduced fertilizers depends on the seeding rate. At the optimal rate of 1.2 million seeds/ha, the highest payback was obtained in the variant with the introduction of 20 kg of a. i. phosphorus and potassium, amounting to 7.7 kg/kg a. i. Conclusions. The best results were obtained when sowing 1.2 million seeds/ha, which pro-vides an opportunity to get the highest conditional net income with high profitability of pro-duction. The maximum conditional net income of 41.7 thousand rubles/ha was observed in the option P₄₀K₄₀, while the profitability of production was 139.39 %, the cost of production was 12.5 thousand rubles/t.

The Dynamics of Nitrogen Valorification in Wheat Crop under the Influence of the Used Agrofound

The study assessed the efficiency of nitrogen use in winter wheat, cultivar ‘Ciprian’ through the combined application of nitrogen with phosphorus fertilizers, between 2016 and 2021. The research was organized within ARDS Lovrin, Timiş County, Romania, under the conditions of a chernozem soil type. The experimental factors considered were: experimental factor A - year of experimentation - six years 2016-2021; experimental factor B -mineral nitrogen fertilizers, with the following graduations: 0 kg N ha-1 (control), 30 kg N ha-1, 60 kg N ha-1,90 kg N ha-1and 120 kg N ha-1; experimental factor C- mineral phosphorus fertilizers, with the following five graduations: 0 kg P ha-1 (control), 40 kg P ha-1, 80 kg P ha 1, 120 kg P ha-1 and 160 kg P ha-1. Production has been taken into consideration for NEU evaluation (Y, kg ha-1), the total nitrogen (Ntot) content (%) of thegrains, N uptake (%) in relation to the experimental factors considered. Differences in NUEs had different significance compared to each experimental factor, and the interaction between A×B, A×C and B×C factors generated differences in statistically safe conditions (p&lt;0.05 in A×C case, and p&lt;0.001 in A×B and B×C case).

The combined application of nitrogen and biochar reduced microbial carbon limitation in irrigated soils of West African urban horticulture

BackgroundIntensive wastewater irrigated urban horticulture in sub-Saharan West Africa receives high nutrient inputs, which lead to large gaseous and leaching losses. The addition of biochar to the usually sandy soils may reduce these losses and improve the habitat conditions for soil microorganisms. Two similar experiments focused on crop yields and nutrient balances have been carried out over a 2-year period in semi-arid Ouagadougou, Burkina Faso, and in sub-humid Tamale, Ghana, representing to some extent different but typical locations in West Africa.MethodsBiochar and N fertilization effects were measured on soil microbial biomass carbon (MBC), fungal ergosterol, and functional diversity, estimated by multi-substrate-induced respiration. It was additionally possible to study the effects of clean water irrigation on the respective microbial properties in Tamale soil.ResultsSole biochar addition did not affect any soil chemical or soil biological properties analyzed. In contrast, biochar application with N fertilization increased the mean respiratory response of the 11 substrates added by 23% in the Ouagadougou soil and by 13% in the Tamale soil. N fertilization decreased soil pH in both cities by 1.1 units. However, a pH-H2O of 4.7 led to reduced MBC and ergosterol contents at Tamale. Also, the Shannon index of the respiratory response was positively correlated with the soil pH. Clean water irrigation decreased the ergosterol content and increased the respiratory response to organic acids.ConclusionsBiochar addition with N fertilization improved habitat conditions for soil microorganisms. An N fertilizer-induced decline in soil pH < 5 should be avoided, as it decreased MBC and microbial functional diversity.Graphical

Growth, Yield and Photosynthetic Performance of Winter Wheat as Affected by Co-Application of Nitrogen Fertilizer and Organic Manures.

The application of organic manures was found to be beneficial, however, the integrated use of organic manures with chemical nitrogen fertilizers has proven more sustainable in increasing the photosynthetic attributes and grain yield of the winter-wheat crop. A multi-factor split-plot design was adopted, nitrogen and manure fertilizer treatments were set in the sub-plots, including nitrogen-gradient treatment of T1:0 kg N ha−1, T2:100 kg N ha−1, T3:200 kg N ha−1, and T4:300 kg N ha−1 (pure nitrogen -fertilizer application) The 25% reduction in nitrogen combined with the manure-fertilizer application includes T5:75 kg N ha−1 nitrogen and 25 kg N ha−1 manure, T6:150 kg N ha−1 nitrogen and 50 kg N ha−1 manure, and T7:225 kg N ha−1 nitrogen and 75 kg N ha−1 manure. The maximum results of the total chlorophyll content and photosynthetic rate were 5.73 mg/g FW and 68.13 m mol m−2 s−1, observed under T4 in Zhongmai 175, as compared to Jindong 22 at the heading stage. However, the maximum results of intercellular CO2 concentration were 1998.47 μmol mol−1, observed under T3 in Jindong 22, as compared to Zhongmai 175 at the tillering stage. The maximum results of LAI were 5.35 (cm2), observed under T7 in Jindong 22, as compared to Zhongmai 175 at the booting stage. However, the maximum results of Tr and Gs were 6.31 mmol H2O m−2 s−1 and 0.90 H2O mol m−2 s−1, respectively, observed under T7 in Zhongmai 175 as compared to Jindong 22 at the flowering stage. The results revealed that grain yield 8696.93 kg ha−1, grains spike−1 51.33 (g), and 1000-grain weight 39.27 (g) were significantly higher, under T3 in Zhongmai 175, as compared to Jindong 22. Moreover, the spike number plot−1 of 656.67 m2 was significantly higher in Jindong 22, as compared to Zhongmai 175. It was concluded from the study that the combined application of nitrogen and manure fertilizers in winter wheat is significant for enhancing seed at the jointing and flowering stages. For increased grain yield and higher economic return, Zhongmai 175 outperformed the other cultivars examined. This research brings awareness toward the nitrogen-fertilizer-management approach established for farmers’ practice, which might be observed as an instruction to increase agricultural management for the winter-wheat-growth season.

Spatial distribution patterns and influencing factors of soil carbon, phosphorus, and C:P ratio on farmlands in southeastern China

Soil organic carbon (SOC), total phosphorus (STP), and the carbon-to-phosphorus ratio (C:P) are important indicators of soil fertility. Knowledge regarding the spatial patterns of SOC, STP, and C:P and their influencing factors are of great significance for precise fertilization, soil management, food security, environmental protection, and global climate change. A total of 16,582 topsoil samples (0–20 cm depth) were collected from farmland in Jiangxi Province, southeastern China. The spatial variability and driving factors of SOC, STP, and C:P were characterized using classical statistics, geostatistical analysis, and random forest (RF) methods. The results showed that the mean values of SOC, STP, and C:P were 17.90 g kg−1, 0.52 g kg−1, and 38.29, and their coefficients of variation were 30.98%, 33.49%, and 45.08%, respectively, indicating a moderate degree of variability. The RF model contained 47 explanatory variables related to parent materials, soil types, soil physicochemical properties, environmental variables, climate, farmland use types, straw returning methods, and fertilizer application rates, which accounted for 72.70%, 60.89%, and 63.71% of the spatial variability in SOC, STP, and C:P, respectively. Soil physicochemical properties had the most significant influence on SOC, STP, and C:P, with contributions of 45.83%, 50.93%, and 51.06%, respectively. Of all the factors, soil total nitrogen was identified as mostly driving the spatial distributions of SOC, STP, and C:P (variable importance of 29.39%, 11.72%, and 23.95%, respectively), followed by the nitrogen application rate (variable importance of 20.90%, 11.37%, 12.79%, respectively). Therefore, conservation tillage, crop rotation, straw return, combined application of nitrogen and phosphorus, and green manure application are the most effective measures for improving carbon sequestration and phosphorus availability. According to the ecological stoichiometry characteristics of carbon, nitrogen, and phosphorus and their temporal variation trends, the farmland soils in Jiangxi Province are typical carbon sink systems that are likely to be limited by phosphorus. The results of this study provide important insights for assessing soil carbon and phosphorus pools and sustainable agricultural development.

长期施肥黄土旱塬农田土壤-微生物-植物系统碳氮磷生态化学计量特征

探讨长期不同施肥制度对农田土壤、植物生态系统的碳（C）、氮（N）、磷（P）含量及其生态化学计量比的影响，可为揭示该系统能量平衡和养分循环，实现农业生态系统元素平衡及可持续发展提供参考意义。以位于黄土高原半干旱地区的长武国家黄土高原农业生态实验站长期施肥试验为研究对象，选取不施肥（CK）、单施氮肥（N）、单施磷肥（P）、施氮磷肥（NP）、单施有机肥（M）、氮肥配施有机肥（NM）、磷肥配施有机肥（PM）、氮磷肥配施有机肥（NPM）8个处理，分析了黄土旱塬典型农田土壤-微生物-植物生态系统中C、N、P含量及其生态化学计量变化规律。研究结果表明：1）长期单施有机肥和化肥配施有机肥处理可显著提高土壤和有机质C、N、P含量。2）氮、磷肥的输入显著降低了土壤和小麦C：N、N：P，施P显著降低了有机态C：P和小麦C：P；有机肥配施对微生物生物量和小麦C：N：P的影响更为明显。3）长期有机肥配施条件下土壤养分和小麦化学计量比存在较强的相关关系。微生物生物量碳与有机C、N、P呈显著正相关，土壤微生物生物量氮与土壤N、P总量呈显著正相关，微生物生物量磷与土壤C、N、P总量含量呈显著负相关；植株碳含量与微生物生物量氮呈显著正相关，植物磷含量与土壤有机磷呈显著正相关。黄土区农田生态系统土壤TC：TP与TC：TN，TN：TP呈正相关，土壤TN：TP与有机碳和有机磷比呈正相关，植物植株C：N与BC：BP、BN：BP呈正相关。长期施肥明显改变了土壤和植物C、N、P含量及化学计量比。氮肥配施有机肥可明显提高微生物对土壤碳素的转化分解，导致有机质和微生物量的化学计量比发生变化，进而提高作物对土壤碳素的固定能力，增强植株对外源养分的输入。;To explore the effects of different fertilization systems on carbon, nitrogen and phosphorus contents and ecological stoichiometric ratio of farmland soil and plant ecosystem in a long time can provide reference for revealing the energy balance and nutrient cycle of the system and realizing the balance and sustainable development of agricultural ecosystem elements. In this study, the long-term fertilization experiment at the Loess Plateau agricultural ecology experimental station of Changwu, located in the semi-arid region of the Loess Plateau, was taken as the research object. No fertilization (CK), single application of nitrogen (N), single application of phosphate (P), single application of nitrogen and phosphate (NP), single application of organic fertilizer (M), combined application of nitrogen and organic fertilizer (NM),application of phosphate and organic fertilizer(PM), and combined application of nitrogen and phosphate and organic fertillizer were selected. The contents of C, N and P in soil, microbe and plant in typical agricultural ecosystem of the Loess Plateau were analyzed, and the change rule of stoichiometry and its influencing factors were analyzed. The results showed that:(I) compared with CK, long-term single application of organic fertilizer and fertilizer combined with organic fertilizer treatment could significantly improve the carbon, nitrogen and phosphorus content of soil and organic matter. (II) With the input of exogenous nitrogen and phosphate fertilizer, compared with CK treatment, N and P treatment significantly reduced soil and wheat C:N and N:P, respectively, and P treatment significantly reduced organic matter and wheat C:P. However, the effect of organic fertilizer combination on microbial biomass and wheat C:N:P was more obvious. (III) There was a significant correlation between soil nutrients and the stoichiometric ratio of wheat under the condition of long-term organic fertilizer application, compared with no fertilization. The results showed that long-term fertilization significantly changed soil carbon, nitrogen and phosphorus contents and stoichiometric ratio, and fertilizer combined with organic fertilizer could significantly improve soil fertility in the xeroxic farmland of loess, resulting in the change of stoichiometric ratio of organic matter and microbial biomass, which had a significant impact on the stoichiometric ratio of wheat plants.

Chemical Composition of High Organic Carbon Soil Amendments Affects Fertilizer-Derived N2O Emission and Nitrogen Immobilization in an Oxic Sandy Loam

Nitrous oxide (N2O) emission is a negative side effect of modern agriculture and a serious issue for global climate change. The combined application of nitrogen (N) fertilizer and high organic carbon soil amendments (HCA) has been regarded as an alternative to promote fertilizer-related N immobilization and enhance nitrogen use efficiency. The effect of HCA on N2O emission and N immobilization highly depends on its chemical composition, as it controls carbon (C) supply to soil microbes and reactivity of lignin-derived phenols to fertilizer-derived N species. Here we present a 127-d laboratory incubation study to explore the N2O emission and N immobilization after combined application of N fertilizer and HCA (wheat straw, spruce sawdust, and commercial alkali lignin) differing in their chemical composition. The 15N labelling technique was used to trace the transformation of fertilizer-N in ammonium (NH4+), NO3-, soil organic nitrogen (SON), and N2O. The amendment of wheat straw and spruce sawdust greatly promoted N immobilization and N2O emission, while lignin amendment enhanced the immobilization of fertilizer N. The chemical composition of HCA explained 26% of the total variance of fertilizer-derived N2O emission and N retention via soil microbial biomass, composition of lignin-derived phenols, and nitrification. The holocellulose/lignin ratio of HCA could be used as an indicator for predicting HCA decomposition, microbial N immobilization and N2O emission. In addition, the composition of lignin-derived phenols was affected by HCA amendment and significantly related to N2O emission and N retention. The varying chemical composition of HCA could thus be a promising tool for controlling N2O emission and N immobilization in environment-friendly and climate-smart agriculture.

Economic Performance and Nutrient Use Efficiency of Onion (Allium Cepa L.) Under N, K and S Nutrient Combinations in Northern Ethiopia

Background: Nitrogen (N), potassium (K) and sulfur (S) nutrient elements play an important role in the growth and bulb yield of onion. However, imbalanced nutrient application leads onion producers to get lower onion bulb yield. Hence, the supply of adequate and balanced plant nutrients is important in order to achieve better nutrient utilization as well as proper growth and high yield. Objective: To evaluate the agronomic and economic performance as well as nutrient efficiency of onion in response to the combined application of nitrogen, potassium and sulfur nutrient levels. Method: The field experiment was conducted during 2016/17 to test agronomic, economic and nutrient use efficiency of eighteen treatment groups with the combination of three levels of N, three levels of K and two levels of S nutrient on onion using a randomized complete block design. Results: The combined application of N, K and S nutrient levels appreciably resulted in significant variation not only on growth and bulb yield of onion but also on the economic performance and nutrient use efficiencies. Increased growth and improved bulb yield of onion as well as better nutrient uptakes and recoveries were observed in plots treated with relatively higher NKS rates. However, enhanced Agronomic Efficiency (AE) and Partial Factor Productivity (PFP) were obtained from plots treated with no N and K nutrient applications. Conclusion: Higher growth, improved bulb yield and enhanced nutrient use efficiencies (nutrient concentrations, uptakes and recoveries) were obtained from onion plants cultivated using a relatively higher NKS nutrient level. However, from the economic point of view, onion production using combined application of 69 kg N ha-1 and 15 kg S ha-1 was the most profitable, irrespective of the K level.

Effect of nitrogen and boron on available nutrients in sesame (Sesamum indicum L.) and harvested soil

A field experiment was carried out at the Soil Science research field of Sher-e-Bangla Agricultural University (SAU), Dhaka-1207, Bangladesh to study the nutrient uptake of sesame plant and available nutrient condition of soil after harvesting of sesame. Sesame variety BARI Til-3 was used as test crop. The experiment consisted of two factors. Factor A: Nitrogen levels (N0-3): N0: 0 kg N/ha (control), N1: 50 kg N/ha, N2: 60 kg N/ha, N3: 70 kg N/ha; Factor B: Boron levels (B0-2): B0: 0 kg B/ha (control), B1: 2 kg B/ha, B2: 3 kg B/ha. The experiment was carried out in two factors Randomized Complete Block Design (RCBD) with three replications. From the study, it was found that nutrient uptake of sesame plant and the nutrient concentration in post-harvested soil such as total N, available P, exchangeable K, available S and available B was increased with the increasing of nitrogen up to a certain level and boron supply. For the combined application of nitrogen and boron (60 kg N/ha and 3.0 kg B/ha) was found suitable to uptake maximum N, P, K, S and B by the sesame plant and to available the highest nutrient concentration in post-harvested soil.&#x0D; Res. Agric., Livest. Fish.6(2): 203-213, August 2019

Effect of Nitrogenous Fertilizer on the Vegetative Growth and Yield Attribute of Pea (Pisum sativum L.)

An experiment was conducted to study the effect of chemical fertilizer on the pea growth and yield attributes. Therefore, the main objective of this study was to investigate the effect of chemical fertilizer alone and in combination. This study consists of three different nitrogen levels (90, 100 and 110 kg ha-1as urea), three different levels of phosphorus (60, 70 and 80 P2O5 kg ha-1 as DAP) and their combination. Treatments were arranged in a complete randomized block design with three replications. The results showed that both the single and combined application of nitrogen and phosphorus fertilizer increased the growth and yield attribute of the pea plant. Maximum number of primary (6.91) and secondary branches per plant (7.97), number of leaves per plant (12.50) and plant height (51.24 cm) was attained by the combine application of P80+N110. Similarly, the maximum increase in yield parameters such as pod length (7.5 cm), number of pods per plant(7.23), pod weight (12.50 g) and number of grains per pod was obtained in P80+N110. In general, combined application of fertilizers significantly increased all the growth and yield attribute of the pea plant when compared to fertilizers applied alone with respect to control.

OPTIMIZING NITROGENOUS FERTILIZER WITH AND WITHOUT COW DUNG ON THE GROWTH AND YIELD OF MAIZE (Zea mays L) IN DIGIL-MUBI, ADAMAWA STATE, NIGERIA

The research, optimizing nitrogenous fertilizer with and without cow dung on the growth and yield of maize (Zea mays L.) in Digil-Mubi, Adamawa state, Nigeria, was conducted in Farm and skills acquisition center Digil -Mubi, to determine the effects of nitrogenous fertilizer with and without cow dung on the growth and yield of maize (Zea mays L.) in the area. Seeds of maize was obtained from the open market in Mubi. Complete randomized design (CRD) was used and replicated three times. The trials were conducted during the 2018 cropping season at Digil - Mubi, Mubi Local Government, Adamawa state, Nigeria. Located in the Northern Guinea Savannah of Nigeria. Digil - Mubi is situated between latitude 100 10’’ and 100 30’’ North of the Equator and between longitude 130 10 and 130 30’’ E of the Greenwich meridian and at an altitude of 696 m above mean sea level (MSL). The results obtained, showed that, there were significant differences at P&lt; 0.05 in terms of yield between treatment two (30Kg N + 0 tone cow dung and 60Kg N + 5 ton cow dung. But there were no significant difference at P&lt; 0.05 in terms of yield between 90Kg N + 5 tones cow dung and 120Kg N + 5 tones cow dung. However, luxuriant growth was observed in 120Kg N + 5 tones cow dung than the 90Kg N + 5 tones cow dung. Similarly, there were no significant difference in yield in the control plot ( 0Kg N + 0 tone cow dung) and 30Kg N + 0 tone cow dung. But the growth performance varies based on the treatment’s combinations. The results obtained from this study showed that, combined application of nitrogen and cow dung in Digil Locality resulted in higher growth, yield and changes in some soil chemical properties than sole application of each nutrient source in the study area. The results also reveals that, the application of 90Kg N + 5 tones of cow dung gave the highest yield of 2,928Kg/ha-1 while 120Kg N + 5 tones of cow dung gave the highest vegetative yield. The lowest grain of 1,796Kg-1 was obtained at 30Kg N + 0 tone of cow dung. The application of 90Kg N + 5 tones of cow dung is therefore recommended in Digil – Mubi and it surroundings for maximum yield and maintenance of soil fertility level in the area.&#x0D;

Grain zinc concentrations differ among Brazilian wheat genotypes and respond to zinc and nitrogen supply.

The combined application of nitrogen (N) and zinc (Zn) fertilizers is a promising agronomic strategy for the biofortification of wheat grain with Zn for human nutrition. A glasshouse experiment was carried out to assess the effects of supplying N on the uptake, translocation and accumulation of Zn in tissues of two wheat genotypes (Quartzo and BRS Parrudo) with contrasting potential for grain Zn biofortification. Winter wheat genotypes were grown to maturity in 5 cm diameter, 100 cm length tubes filled with a mixture of sand, grit and gravel (40:40:20 v/v/v) over a layer of 0.1 m3 of gravel, and supplied a full nutrient solution with low Zn (0.15 μM) or high Zn (2.25 μM) and low N (0.4 mM) or high N (4.0 mM) concentrations. High N supply increased biomass production, Zn concentration and Zn content of straw and grain in both Quartzo and BRS Parrudo. Grain Zn content more than doubled when the supplies of Zn and N were both increased from low to high in both genotypes. Quartzo had a greater grain yield than BRS Parrudo. BRS Parrudo had greater grain Zn concentration and Zn content than Quartzo. A greater N supply promoted better uptake, translocation to the shoot and accumulation of Zn within the grain. Quartzo and BRS Parrudo differed in their partitioning of biomass and Zn between tissues. It might be possible to combine the greater grain yield of Quartzo with the greater grain Zn accumulation of BRS Parrudo to deliver a greatly improved genotype for human food security.

Effect of different levels of nitrogen and phosphorus on nutrient uptake and quality of soybean [Glycine max (L.) Merrill

A field experiment was conducted to study the effect of different levels of nitrogen and phosphorus on nutrient uptake and quality of soybean during kharif 2015. There were twelve treatment combinations consisted of three levels of nitrogen (20, 40 and 60 kg N/ha) and four levels of phosphorus (40, 60, 80 and 100 kg P2O5/ha). Significantly higher soybean seed yield (25.77 q/ha), haulm yield (31.32 q/ha), uptake of nitrogen (209.16 kg/ha), phosphorus (28.09 kg/ha), potassium (114.47 kg/ha) and protein yield (8.81 q/ha) recorded with combined application of nitrogen @ 60 kg/ha and phosphorus @ 80 kg/ha compared to other treatments and it was on par with application of nitrogen @ 60 kg/ha and phosphorus @ 100 kg/ha. Application of nitrogen @ 60 kg, phosphorus @ 80 kg and potash @ 25 kg per hectare found optimum to obtain substantial soybean seed yield.

Influence of graded level of nitrogen and sulphur on growth in tuberose (Polianthes tuberose L.) CV. Double

The Present study indicates that the growth contributing character of tuberose cv. double growth was significantly influence by various nitrogen and sulphur. Among different nitrogen and sulphur combined application of nitrogen @ 240kg/ha and sulphur 100kg/ha recorded the significantly the highest growth parameter viz., number of laves/plant (115.40) and number of days taken for sprouting (10.00) was recorded with N3 (@ 240kg/ha + S2 @ 100Kg/ha)