Efficacy Of Nitrogen Research Articles

Substrate preference of Tetrasphaera in dual PAOs synergistic EBPR system and its phosphorus removal performance

In this study, an alternated anaerobic/aerobic sequencing batch reactor (SBR) was employed to investigate the effect of the substrate conversion from casein hydrolysate (Cas aa) to a mixture of amino acids (glutamate, aspartate, glycine and proline) on the efficacy of nitrogen and phosphorus removal in an enhanced biological phosphorus removal (EBPR) system characterized by dual polyphosphate-accumulating organisms (PAOs), mainly focusing on the substrate preference of fermentative PAOs. The results indicated that a stable removal efficiency was found to be above 90 % as the substrate was converted to the mixture of amino acids. Meanwhile, the removal efficiency of ammonium eventually increased to over 95 % in stage III, despite an increase of ammonia nitrogen by hydrolysis with the rising proportion of mixed amino acids in influent. Moreover, shortening the anaerobic duration did not significantly affect the phosphorus removal performance, even enhancing anaerobic phosphorus release capacity. Nevertheless, the ammonia nitrogen removal was influenced. 16 s rRNA high-throughput sequencing results demonstrated that the detected fermentative PAO like Tetrasphaera in the EBPR system exhibited a clear preference for utilizing mixed amino acids and could cooperate with traditional PAO like Accumulibacter for phosphorus removal. In addition, the fermentation of amino acids mixture by Tetrasphaera was more pronounced and its abundance increased under the condition of a shorter anaerobic duration, leading to a relatively stable and high abundance of Accumulibacter in the presence of sufficient substrates from Tetrasphaera. However, considering the nitrogen removal performance and steady operation of the EBPR system, a longer anaerobic duration was more reasonable.

Efficacy of nitrogen and Azolla spp. on growth and yield of black rice (Oryza sativa L.)

An experimental field study was carried out in the Kharif season of 2023 at the Crop Research Farm, Department of Agronomy, SHUATS, Prayagraj (U.P.). The experimental replications were conducted using a Randomized Block Design, with three levels of Nitrogen (0, 60, 90kg N/ha) and Azolla spp. (2, 4, 6t/ha), and one Control (NPK 120:60:60 kg/ha). In all, there were a total of ten treatments, each reproduced three times. The tested field had sandy loam soil texture with a neutral soil pH of 7.6, low organic carbon content of 0.372%, nitrogen content of 278.4 kg/ha, phosphorous content of 29.5 kg/ha, and potassium level of 217.3 kg/ha. The experimental results showed that treatment T₉ obtained significantly higher plant height (107.77 cm), dry weight (66.05 g), crop growth rate (57.27 g/m2/day), relative growth rate (0.0279 g/g/day), highest number of tillers per hill (22.07), panicles per m2 (282), test weight (15.23 g), grain yield (3.67 t/ha), stover yield (6.7 t/ha), and harvest index (35.74%). Transplanted Black Rice of variety BPT-2841 exhibited significantly greater maximum gross return (1,80,551.40 INR/ha), net return (1,05,496.30 INR/ha), and B:C ratio (1.41) in treatment T9. The investigation concludes that Nitrogen, being easily transportable in soil and plants, is a constituent of amino acids, nucleic acids, chlorophyll, enzymes, and hormones. These factors are essential in plant physiology and are associated with increased tillering, biomass production, protein synthesis, grain filling, yield, and quality. The availability, absorption, and utilization of nitrogen have a significant impact on these processes. Therefore, in the present experiment, the nitrogen requirements are met by applying 90kg of nitrogen through urea combined with 6t/ha of Azolla spp. This approach revealed superior performance in terms of both crop yield and economic returns .

Adaptive growth strategies of Quercus dentata to drought and nitrogen enrichment: a physiological and biochemical perspective.

Nitrogen deposition and drought significantly influence plant growth and soil physicochemical properties. This study investigates the effects of nitrogen deposition and water stress on the growth and physiological responses of Quercus dentata, and how these factors interact to influence the overall productivity. Two-year-old potted seedlings were selected to simulate nitrogen deposition and water stress. Nitrogen was applied at rates of 0 kg·ha-1·year-1 (N0) and 150 kg·ha-1·year-1 (N150). The levels of water stress corresponded to 80% (W80), 50% (W50), and 20% (W20) of soil saturation moisture content. High nitrogen (N150) significantly increased stem elongation and stem diameter by enhancing photosynthetic parameters, including P n (W80) and G s (W50), and maintained higher water use efficiency. Under drought conditions, nitrogen enhanced leaf water content, stabilized electrical conductivity, regulated antioxidant enzyme activity, and increased the accumulation of proline. However, under severe drought, nitrogen did not significantly improve biomass, highlighting the critical role of water availability. Additionally, increased nitrogen levels enhanced soil enzyme activity, facilitated the uptake of crucial nutrients like K and Zn. Mantel tests indicated significant correlations between soil enzyme activity, water use efficiency, and leaf Fe content, suggesting that nitrogen deposition altered nutrient uptake strategies in Q. dentata to sustain normal photosynthetic capacity under water stress. This study demonstrates that nitrogen deposition substantially enhances the growth and physiological resilience of Q. dentata under W50 by optimizing photosynthetic efficiency, water use efficiency, and nutrient uptake. However, the efficacy of nitrogen is highly dependent on water availability, highlighting the necessity of integrated nutrient and water management for plant growth.

Efficacy of Nitrogen and Phosphorus Removal and Microbial Characterization of Combined A2O-MBBR Constructed Wetlands

A combined anaerobic–anoxic–oxic moving bed biofilm reactor (A2O-MBBR) constructed wetlands process was used to treat low carbon-to-nitrogen (C/N) simulated sewage. The results showed that the removal rates of chemical oxygen demand (COD), ammonia nitrogen (NH4+-N), total nitrogen (TN), and total phosphorus (TP) by this process were 94.06%, 94.40%, 67.11%, and 84.57%, respectively, and the concentrations of COD, NH4+-N, TN, and TP in the effluent were lower than the Class I-A standard of GB18918-2002. In the anoxic zone, NH4+-N had an inhibitory effect on phosphorus uptake via phosphorus-accumulating organisms (PAOs). The highest community diversity was observed in the anoxic zone sludge at 24 d. During the water-quality-shock loads stage, microbial community diversity decreased in a combined A2O-MBBR constructed wetlands reactor. At the phylum level, bacteria within the mature activated sludge were dominated by Proteobacteria, while Planctomycetes bacteria were the dominant species in the constructed wetlands. At the genus level, Tolumonas spp. were the dominant species in the 12 d and 24 d constructed wetlands and the anaerobic zone, with relative abundance percentages ranging from 20.24 to 33.91%. In the water-quality-shock loads stage, they were replaced by denitrifying bacteria such as Herbaspirillum spp. Unclassified_Burkholderiales was the dominant species in the constructed wetlands, with a relative abundance of 33.09%.

Efficacy of Nitrogen against Stored Product Insects with Different Susceptibility Levels to Phosphine in Industrial Applications

We carried out trials on the commercial applications of nitrogen in different industrial structures, using phosphine-susceptible and -resistant populations of three stored product beetle species, the red flour beetle, Tribolium castaneum (Herbst) (Coleoptera: Tenebrionidae), the rice weevil, Sitophilus oryzae (L.) (Coleoptera: Curculionidae), and the saw-toothed grain beetle, Oryzaephilus surinamensis (L.) (Coleoptera: Silvanidae). Twelve different trials were conducted in total, five in chambers and seven in large silos in Greece, following different temperatures and exposure times. In most of our trials, complete mortality was recorded, with the exception of two silos in which survival was recorded for T. castaneum and O. surinamensis, while S. oryzae was classified as the most susceptible species. Moreover, low or no progeny production was recorded for most of the trials. Our results indicate that nitrogen, through the reduction in the oxygen level, could be used for the control of stored product insects that are resistant to phosphine, and can be further utilized in resistance management strategies.

Efficacy of Nitrogen and Zinc Application at Different Growth Stages on Yield, Grain Zinc, and Nitrogen Concentration in Rice

Zinc (Zn) is an essential element involved in human metabolism, which can be supplied by an appropriate diet. Enhancing Zn enrichment in rice grains through agronomic biofortification is advocated as an immediate and effective approach to combat micronutrient malnutrition in hu-man. It has been well-documented that high grain Zn accumulation in rice can be achieved by Zn fertilizers management. This study evaluated the effects of foliar nitrogen (N) and Zn applied at the flowering and milky stages of brown rice plants with and without soil Zn application. A glasshouse pot experiment was conducted using a completely randomized design with four replicates. Soil Zn in the form of ZnSO4 was applied at 0 and 50 kg ha−1. Foliar fertilizer of 1% urea along with 0.5% ZnSO4 was applied and assigned as (1) nil foliar N and Zn (N0Zn0), (2) foliar N with nil Zn (N+Zn0), (3) nil foliar N with foliar Zn (N0Zn+), and (4) foliar N and Zn (N+Zn+) at flowering and milky stages. Foliar application of N and Zn increased grain yield and yield components in both soil Zn conditions. Grain Zn concentration in brown rice was the highest when foliar N and Zn were applied under nil soil Zn conditions; however, grain N concentration decreased by 13.1–28.5% with foliar application at flowering and 18.8–28.5% with application at the milky stage. The grain Zn content was increased by foliar application of N0Zn+ and N+Zn+ at flowering and milky stages. Applying foliar N and Zn at flowering or milky stages tended to increase the grain N content when Zn was applied to the soil, while nil soil Zn decreased the N content by 26.8% at flowering and milky stages under N0Zn+. The results suggest that the milky stage is the most suitable for foliar application of Zn for increasing (i) grain yield and (ii) N and Zn concentrations in brown rice without having a dilution effect.

Evaluation of nitrogen-delivery methods for stocker cattle grazing annual ryegrass.

A 2-yr grazing experiment was conducted to evaluate efficacy of nitrogen (N) fertilization, interseeded legumes, and protein supplementation for N delivery to stocker cattle grazing annual ryegrass (Lolium multiflorum). Each year, 90 steers (initial BW, 241 ± 13 kg) were assigned to the following N-delivery methods, with or without monensin fed in a free-choice mineral supplement as a 5 × 2 factorial arrangement of treatments: ryegrass fertilized with 112 kg N/ha (NFERT); ryegrass interseeded with crimson clover (CC, Trifolium incarnatum); ryegrass interseeded with arrowleaf clover (AC, Trifolium vesiculosum); ryegrass plus distillers dried grains with solubles (DDGS) supplemented at 0.65% BW daily; and ryegrass plus whole cottonseed (WCS) supplemented at 0.65% BW daily. Pastures within the interseeded-clover and protein-supplementation treatments were fertilized with 56 kg N/ha at time of establishment. Steers were weighed every 28 d, and forage mass (FM, kg DM/ha) was measured concurrently using the destructive harvest/disk meter double-sampling method. Each of 30 0.81-ha paddocks was stocked initially with 3 “tester” steers, and stocking density (steers/ha) was adjusted using “put-and-take steers” based on changes in FM and steer BW in order to maintain a uniform forage allowance (FA) of 1 kg DM/kg steer BW. Grazing was discontinued on May 11, 2016 in Yr 1 and May 10, 2017 in Yr 2 following 140 and 84 d of grazing, respectively. Data were analyzed as a completely randomized design with repeated measures for which pasture (n = 3) was the experimental unit. Ionophore inclusion did not affect (P > 0.10) any variable measured. Mean FM differed (P < 0.0001) between years and among N-delivery methods (P < 0.10), and mean FA differed (P = 0.005) among N-delivery methods. Steer ADG differed among N-delivery methods (P = 0.02) and between years (P < 0.001), whereas total gain/ha differed (P < 0.0008) among N-delivery methods, but not between years (P = 0.78). Stocking density differed among N-delivery methods (P = 0.02) and between years (P < 0.0001), and grazing-days/ha differed between years (P < 0.0001) and among N-delivery methods (P = 0.001). Results indicate that supplementation with a high-protein by-product feed for cattle grazing annual ryegrass maintained ADG, total gain/ha and grazing-days/ha compared with N-fertilized annual ryegrass, and increased ADG, total gain/ha, and grazing-days over interseeded legumes.

Research Progress on Water Purification Efficiency of Multiplant Combination in Constructed Wetland

The constructed wetland has the powerful purification sewage function, the plant is the core of the constructed wetland, playing the vital role in the water body decontamination restoration process. The common plant species in constructed wetland were summarized and classified (floating plants, floating plants, emergent plants, submerged plants, ornamental plants and economical plants). The factors and basic principles that need to be considered when configuring a variety of plants in a constructed wetland combination for decontamination are described, including decontamination purification capacity, environmental adaptability, and the economic and ornamental value of multiple plants, etc. The current research contents and directions are emphatically reviewed, focusing on the functions and efficacy of nitrogen and phosphorus removal and purification of heavy metal wastewater by various plant combinations in constructed wetlands. It is pointed out that there are many shortcomings in the research of decontamination process of many plants, such as imperfect planting standards, lacking of research on the mechanism of decontamination among various plants, between various plants and substrates, and root microorganisms. Many kinds of plants have not been dealt with properly after harvesting, resulting in waste of resources and secondary pollution and other problems. Therefore, in the future research on the purification and restoration of various plant waters in constructed wetlands, a universally applicable planting specification for various plants in constructed wetlands should be formulated; exploring and analyzing how various plants and various plants interact with substrates and root microorganisms function to achieve water purification and repair effects; In addition, fuel ethanol technology, Biogas fermentation and biomass solid fuel technology should be developed to realize the resource reuse of wetland plants and improve the purification efficiency of wetland plants.

052 Evaluation of Nitrogen Delivery Methods for Stocker Cattle Grazing Annual Ryegrass

A 2-yr grazing experiment was conducted to evaluate efficacy of nitrogen (N) fertilization, interseeded legumes, and protein supplementation for N delivery to stocker cattle grazing annual ryegrass (Lolium multiflorum). Each year, 90 steers (initial BW, 241 ± 13 kg) were assigned to the following N-delivery methods, with or without monensin fed in a free-choice mineral supplement as a 5 × 2 factorial arrangement of treatments: ryegrass fertilized with 112 kg N/ha (NFERT); ryegrass interseeded with crimson clover (CC, Trifolium incarnatum); ryegrass interseeded with arrowleaf clover (AC, Trifolium vesiculosum); ryegrass plus distillers dried grains with solubles (DDGS) supplemented at 0.65% BW daily; and ryegrass plus whole cottonseed (WCS) supplemented at 0.65% BW daily. Pastures within the interseeded-clover and protein-supplementation treatments were fertilized with 56 kg N/ha at time of establishment. Steers were weighed every 28 d, and forage mass (FM, kg DM/ha) was measured concurrently using the destructive harvest/disk meter double-sampling method. Each of 30 0.81-ha paddocks was stocked initially with 3 "tester" steers, and stocking density (steers/ha) was adjusted using "put-and-take steers" based on changes in FM and steer BW in order to maintain a uniform forage allowance (FA) of 1 kg DM/kg steer BW. Grazing was discontinued on May 11, 2016 in Yr 1 and May 10, 2017 in Yr 2 following 140 and 84 d of grazing, respectively. Data were analyzed as a completely randomized design with repeated measures for which pasture (n = 3) was the experimental unit. Ionophore inclusion did not affect (P > 0.10) any variable measured. Mean FM differed (P < 0.0001) between years and among N-delivery methods (P < 0.10), and mean FA differed (P = 0.005) among N-delivery methods. Steer ADG differed among N-delivery methods (P = 0.02) and between years (P < 0.001), whereas total gain/ha differed (P < 0.0008) among N-delivery methods, but not between years (P = 0.78). Stocking density differed among N-delivery methods (P = 0.02) and between years (P < 0.0001), and grazing-days/ha differed between years (P < 0.0001) and among N-delivery methods (P = 0.001). Results indicate that supplementation with a high-protein by-product feed for cattle grazing annual ryegrass maintained ADG, total gain/ha and grazing-days/ha compared with N-fertilized annual ryegrass, and increased ADG, total gain/ha, and grazing-days over interseeded legumes.

Effect of calcium and nitrogen fertilization on bacterial canker susceptibility in stone fruits

Introduction . Bacterial canker, caused by Pseudomonas syringae pv. syringae , is a destructive disease where stone fruit trees are cultivated. The efficacy of nitrogen and calcium fertilization on bacterial canker susceptibility was evaluated in stone fruits. Materials and methods . Field experiments were conducted to study the efficacy of foliar applications of calcium nitrate, and ground fertilization with CAN-17 plus low-biuret urea foliar spray on bacterial susceptibility in ‘Riegel’ peach, ‘French’ prune and ‘Nonpareil’ almond growing in ring nematode-infested and nematicide-fumigated soils. Host susceptibility was evaluated by measuring the length of lesions developed following inoculation with P. syringae pv. syringae . Results and discussion . Foliar applications of Ca(NO3 )2 significantly increased leaf nitrogen and bark calcium concentrations in peach trees growing in both fumigated and nonfumigated areas. Peach trees growing in nonfumigated areas developed significantly longer lesions than trees growing in fumigated areas. However, Ca(NO3 )2 foliar applications had no effect in decreasing peach susceptibility to bacterial infection in both nonfumigated and fumigated areas. After inoculation, diseased prune trees developed significantly longer lesions than healthy trees. Leaf and bark calcium concentrations of diseased prune were significantly increased after Ca(NO3 )2 foliar sprays, but again the treatments did not significantly affect prune susceptibility to bacterial infection. However, nitrogen fertilization with CAN-17 and urea significantly increased the bark nitrogen concentration of almond trees, and these trees had significantly smaller lesions than those not receiving nitrogen fertilization. Foliar application of calcium (Nutri-Cal) did not affect almond susceptibility to bacterial canker. Collectively, these data support the previous hypothesis that increased susceptibility of stone fruits to P. syringae pv. syringae under nematode infestation conditions is mediated by both nitrogen effects and nitrogen-independent effects, and application of ammonium nitrogen may have some beneficial effects in reducing stone fruit susceptibility to bacterial canker where ring nematode infestation prevails.

Why nitrogen cannot lead to p-type conductivity in ZnO

Based on electronic structure and atomic size considerations, nitrogen has been regarded as the most suitable impurity for p-type doping in ZnO. However, numerous experimental efforts by many different groups have not resulted in stable and reproducible p-type material, casting doubt on the efficacy of nitrogen as a shallow acceptor. Based on advanced first-principles calculations we find that nitrogen is actually a deep acceptor, with an exceedingly high ionization energy of 1.3 eV, and hence cannot lead to hole conductivity in ZnO. In light of this result, we reexamine prior experiments on nitrogen doping of ZnO.

Efficacy of nitrogen on the growth and yield of maize (Zea Mays L.) in Obubra, Cross River State

Two field experiments were conducted to determine the efficacy of Nitrogen fertilizer on the growth and yield of improved maize variety in the teaching and research farm department of Agronomy Obubra, Cross River University of Technology during the 2003 / 2004 cropping seasons. The experiment comprised seven rates of Urea (46% N) fertilizer at 0, 50, 90, 130, 170, 210 and 250 kg/ha with three replications. Urea application significantly increased plant height, number of leaves and ear weight, ear length and ear diameter per plant. The use of 210kg/ha Nitrogen produced the best maize grain yield of 2.43 and 2.96 tons/has in 2003 and 2004 cropping seasons respectively. Keywords: efficacy of nitrogen, growth, yieldJournal of Agriculture, Forestry and the Social Sciences vOL 3(1) 2005: 35-40