Nitrogen use efficiency: re-consideration of the bioengineering approach

Botany ◽  
2010 ◽  
Vol 88 (2) ◽  
pp. 103-109 ◽  
Author(s):  
Elizabeth K. Brauer ◽  
Barry J. Shelp
Keyword(s):  
Glutamate Synthase ◽  
Utilization Efficiency ◽  
Molecular Physiology ◽  
Physiological Mechanisms ◽  
Breeding Programs ◽  
Molecular Approaches ◽  
Starting Point ◽  
N Assimilation ◽  
Use Efficiency ◽  
N Use

There is considerable confusion about N use efficiency (NUE) in the plant literature. We would like to propose the simple and ubiquitous definitions described by Good et al. (2004) as a starting point for studies of NUE. Based on this terminology, there is evidence from breeding programs for variation in both uptake efficiency (UpE) and utilization efficiency (UtE). Molecular physiology studies typically address mechanisms for improving NUE, but often do not calculate NUE or even acquire appropriate data for calculating NUE. Herein, we report in detail on recent studies involving molecular approaches for improving NUE, and calculate changes in NUE where possible. The evidence suggests that there is potential for improving usage index and UpE in dicots and UpE and UtE in monocots by overexpressing enzymes for N assimilation, specifically glutamine synthetase 1, glutamate synthase, and alanine aminotransferase. If decreased fertilizer-N input and improved NUE are truly goals of the plant biology community, researchers are encouraged to (i) consider the use of both wild type and azygous controls, (ii) compare general NUE (on the basis of grain or biomass yield per unit of applied N) of overexpression mutants and controls at both limiting and non-limiting N levels, (iii) select an appropriate type of specific NUE for assessing the physiological mechanisms involved (uptake versus internal utilization), and (iv) confirm promising results under field conditions.

The effect of grazing season length on nitrogen utilization efficiency and nitrogen balance in spring-calving dairy production systems

2012 ◽  
Vol 150 (5) ◽  
pp. 630-643 ◽  
Author(s):  
W. RYAN ◽  
D. HENNESSY ◽  
T. M. BOLAND ◽  
L. SHALLOO
Keyword(s):  
Milk Production ◽  
Production Systems ◽  
Utilization Efficiency ◽  
N Use Efficiency ◽  
Dairy Production ◽  
N Losses ◽  
Grazing Season ◽  
Use Efficiency ◽  
Milk Solids ◽  
N Use

SUMMARYThere is a continual requirement for grass-based production systems to optimize economic and environmental sustainability through increased efficiency in the use of all inputs, especially nitrogen (N). An N balance model was used to assess N use efficiency and N surplus, and to predict N losses from grass-based dairy production systems differing in the length of the grazing season (GS). Data from a 3-year grazing study with a 3×3 factorial design, with three turnout dates (1 February, 21 February and 15 March) and three housing dates (25 October, 10 November and 25 November) were used to generate estimates of N use efficiency and N losses. As the length of the GS increased by a mean of 30 days, milk production, milk solids production and milk N output increased by 3, 6 and 6%, respectively. The increase in milk production as the length of the GS increased resulted in a 2% decline in N surplus and a 5% increase in N use efficiency. Increasing GS length increased the proportion of grazed grass in the diet, which increased N cycling within the system, resulting in an 8% increase in milk solids/ha produced/kg of surplus N. The increased cycling of N reduced the quantity of N partitioned for loss to the environment by 8%. Reducing fertilizer N input by 20% increased N use efficiency by 22% and reduced total N losses by 16%. The environmental and production consequences of increased length of the GS and reduced N loss are favourable as the costs associated with N inputs increase.

scholarly journals Efficiency of Mineral Nitrogen Fertilization in Winter Wheat under Pannonian Climate Conditions

Agriculture ◽  
2020 ◽  
Vol 10 (11) ◽  
pp. 541
Author(s):  
Gerhard Moitzi ◽  
Reinhard W. Neugschwandtner ◽  
Hans-Peter Kaul ◽  
Helmut Wagentristl
Keyword(s):  
Winter Wheat ◽  
Grain Yield ◽  
Ammonium Nitrate ◽  
Utilization Efficiency ◽  
N Use Efficiency ◽  
N Recovery ◽  
N Loss ◽  
Calcium Ammonium Nitrate ◽  
Use Efficiency ◽  
N Use

Improvements in nitrogen (N) use efficiency in crop production are important for addressing the triple challenges of food security, environmental degradation and climate change. The three fertilizers, calcium ammonium nitrate (CAN), urea (Urea) and stabilized urea (Ureastab), were applied at a rate of 160 kg N ha−1 with two or three splits to winter wheat (Triticum aestivum L.) in the Pannonian climate region of eastern Austria. On average, over all fertilization treatments, the grain yield (GY) increased by about a quarter and the grain N concentration (GNC) doubled compared to the control without fertilization. Consequently, the grain N yield (NYGRAIN) was increased with N fertilization by 154%. The GY increased due to a higher grain density with no differences between N fertilizers but with a tendency of a higher grain yield with three compared to two splits. Three splits also slightly increased the GNC and consequently the NYGRAIN of CAN and Ureastab in one year. The removal of N fertilizer with the NYGRAIN (N surplus) was higher than the amount of applied fertilizer. Fertilization decreased the N use efficiency (NUE), the N uptake efficiency (NUpE) and the N utilization efficiency (NUtE) but increased the soil mineral nitrate (NO3-N) at harvest and the apparent N loss (ANL). Three compared to two applications resulted in a higher NO3-N at harvest but also a lower N surplus due to partly higher NYGRAIN. Consequently, the ANL was lower with three compared to two splits. Also, the NUpE and the apparent N recovery efficiency (ANRE) were higher with three splits. The best N treatment regarding highest above-ground biomass yield with lowest N surplus, N balance and ANL was the three-split treatment (50 CAN, 50 CAN, 60 liquid urea ammonium nitrate). Three splits can, under semi-arid conditions, be beneficial when aiming high-quality wheat for bread-making and also for reducing the N loss. Whereas, two splits are recommended when aiming only at high GY, e.g., for ethanol-wheat production.

scholarly journals Cyanobacterial NOS expression improves nitrogen use efficiency, nitrogen-deficiency tolerance and yield in Arabidopsis

2020 ◽  
Author(s):  
Del Castello Fiorella ◽  
Foresi Noelia ◽  
Nejamkin Andrés ◽  
Lindermayr Christian ◽  
Buegger Franz ◽  
...  
Keyword(s):  
Nitric Oxide ◽  
Seed Production ◽  
N Uptake ◽  
Nitrogen Deficiency ◽  
N Assimilation ◽  
N Metabolism ◽  
Use Efficiency ◽  
Oxide Synthase ◽  
Positive Effect ◽  
N Use

ABSTRACTDeveloping strategies to improve nitrogen (N) use efficiency (NUE) in plants is a challenge to reduce environmental problems linked to over-fertilization. The nitric oxide synthase (NOS) enzyme from the cyanobacteria Synechococcus PCC 7335 (SyNOS) has been recently identified and characterized. SyNOS catalyzes the conversion of arginine to citrulline and nitric oxide (NO), and then 70% of the produced NO is rapidly oxidized to nitrate by an unusual globin domain in its 5'-terminus. In this study, we assessed whether SyNOS expression in plants affects N metabolism improving NUE and yield. Our results showed that transgenic Arabidopsis plants had higher primary shoot length and shoot branching when grown in N-deficient conditions and higher seed production in N-sufficient and -deficient conditions. Moreover, transgenic plants showed significantly increased NUE in both N conditions. No differences were observed in N uptake for SyNOS lines. However, SyNOS lines presented an increase in N assimilation/remobilization under low N conditions. In addition, SyNOS lines had greater N-deficiency tolerance compared to wt plants. Our results support that SyNOS expression generates a positive effect on N metabolism and seed production in Arabidopsis, and it might be envisaged as a strategy to improve productivity in crops under adverse N environments.

scholarly journals NITROGEN USE EFFICIENCY IN SWEETPOTATO

HortScience ◽  
1996 ◽  
Vol 31 (5) ◽  
pp. 761c-761
Author(s):  
Kenneth V. Pecota ◽  
Wanda W. Collins
Keyword(s):  
Genotypic Variation ◽  
N Fertilizer ◽  
Utilization Efficiency ◽  
Genotypic Differences ◽  
Regression Equations ◽  
Marketable Yield ◽  
Nitrogen Use ◽  
Uptake Efficiency ◽  
Use Efficiency ◽  
N Use

Eight clones of sweetpotato [Ipomaea batatas (L.) Lam.] at five N levels in 1992 and five clones at three N levels in 1993 were evaluated for genotypic variation in N use efficiency [NUE (yield/unit N fertilizer applied)], uptake efficiency (N accumulated/unit N fertilizer applied), and utilization efficiency (yield/N accumulated). There were significant genotypic differences for all NUE components and the variables used for calculation. When total marketable yield was used in calculating NUE, utilization efficiency was always more important than uptake efficiency in accounting for NUE variation. Regression equations developed from 1992 NUE components and selected non-N variables used to calculate them ranked the 1993 NUE components correctly when averaged over all clones. Uptake efficiency could be predicted by biomass; utilization efficiency by total marketable yield.

scholarly journals Can Different Salt Formulations Revert the Depressing Effect of Salinity on Maize by Modulating Plant Biochemical Attributes and Activating Stress Regulators through Improved N Supply?

2021 ◽  
Vol 13 (14) ◽  
pp. 8022
Author(s):  
Syed Ayyaz Javed ◽  
Muhammad Saleem Arif ◽  
Sher Muhammad Shahzad ◽  
Muhammad Ashraf ◽  
Rizwana Kausar ◽  
...  
Keyword(s):  
Maize Plant ◽  
Control Treatment ◽  
Optimum Level ◽  
Maize Crop ◽  
Application Rates ◽  
N Assimilation ◽  
Salinity Levels ◽  
Use Efficiency ◽  
Physiological And Biochemical ◽  
N Use

Salinity is a major constraint in improving agricultural productivity due to its adverse impact on various physiological and biochemical attributes of plants, and its effect on reducing nitrogen (N) use efficiency due to ion toxicity. To understand the relationship between sodium chloride (NaCl) and increased N application rates, a pot study was performed in which the ammonical (NH4+) form of N was applied as urea to maize crops at different rates (control, 160, 186, 240, 267, 293, and 320 kg N ha−1) using two salinity levels (control and 10 dS m−1 NaCl). The results indicate that all biochemical and physiological attributes of the maize plant improved with increased concentration of N up to 293 kg ha−1, compared to those in the control treatment. Similarly, the optimal N concentration regulated the activities of antioxidant enzymes, i.e., catalase activity (CAT), peroxidase activity (POD), and superoxide dismutases (SOD), and also increased the N use efficiencies of the maize crop up to 293 kg N ha−1. Overall, our results show that the optimum level of N (293 kg ha−1) improved the salinity tolerance in the maize plant by activating stress coping physiological and biochemical mechanisms. This may have been due to the major role of N in the metabolic activity of plants and N assimilation enzymes activity such as nitrate reductase (NR) and nitrite reductase (NiR).

scholarly journals Methods to classify maize cultivars in use efficiency and response to nitrogen

Revista CERES ◽  
2013 ◽  
Vol 60 (5) ◽  
pp. 699-705
Author(s):  
Cleiton Lacerda Godoy ◽  
Glauco Vieira Miranda ◽  
Rodrigo Oliveira DeLima ◽  
Leandro Vagno de Souza ◽  
João Carlos Cardoso Galvão ◽  
...  
Keyword(s):  
Regression Analysis ◽  
Plant Breeding ◽  
Low Cost ◽  
Fast Response ◽  
N Availability ◽  
Breeding Programs ◽  
Maize Cultivars ◽  
Use Efficiency ◽  
High Repeatability ◽  
N Use

n plant breeding programs that aim to obtain cultivars with nitrogen (N) use efficiency, the focus is on methods of selection and experimental procedures that present low cost, fast response, high repeatability, and can be applied to a large number of cultivars. Thus, the objectives of this study were to classify maize cultivars regarding their use efficiency and response to N in a breeding program, and to validate the methodology with contrasting doses of the nutrient. The experimental design was a randomized block with the treatments arranged in a split-plot scheme with three replicates and five N doses (0, 30, 60, 120 and 200 kg ha-1) in the plots, and six cultivars in subplots. We compared a method examining the efficiency and response (ER) with two contrasting doses of N. After that, the analysis of variance, mean comparison and regression analysis were performed. In conclusion, the method of the use efficiency and response based on two N levels classifies the cultivars in the same way as the regression analysis, and it is appropriate in plant breeding routine. Thus, it is necessary to identify the levels of N required to discriminate maize cultivars in conditions of low and high N availability in plant breeding programs that aim to obtain efficient and responsive cultivars. Moreover, the analysis of the interaction genotype x environment at experiments with contrasting doses is always required, even when the interaction is not significant.

scholarly journals Genotypic Variation in Nitrogen Use-Efficiency Traits of 28 Tobacco Genotypes

Agronomy ◽  
2020 ◽  
Vol 10 (4) ◽  
pp. 572
Author(s):  
André B. Andrade ◽  
Douglas R. Guelfi ◽  
Valdemar Faquin ◽  
Fabrício S. Coelho ◽  
Carolina S. de C. Souza ◽  
...  
Keyword(s):  
Nitrogen Use Efficiency ◽  
N Uptake ◽  
Genotypic Variation ◽  
Sustainable Use ◽  
Utilization Efficiency ◽  
N Availability ◽  
Nitrogen Use ◽  
N Supply ◽  
Use Efficiency ◽  
N Use

Knowing the nitrogen use efficiency (NUE) of crops is crucial to minimize environmental pollution, although NUE is rarely provided for numerous genotypes in the tobacco (Nicotiana tabacum L.) crop. Through the growth of contrasting genotypes in nutritive solutions, we aimed to characterize five NUE components of 28 genotypes and to classify them according to their efficiency and responsiveness to nitrogen (N) availability. On average, physiological N use efficiency, N harvest index, and N uptake efficiency decreased by 16%, 4%, and 57%, respectively, under N-deficient conditions, while N utilization efficiency decreased by 43% at adequate N supply. The relative efficiency of N use varied from 35% to 59% among genotypes. All genotypes of the Virginia and Maryland varietal groups were efficient, and those of the Burley, Comum, and Dark groups were inefficient, while the responsiveness varied among genotypes within varietal groups, except for Maryland genotypes. Our findings are helpful in indicating genotypes with distinguished efficiency and responsiveness to N supply, which can be further chosen according to soil N level or affordability to N fertilizers worldwide in tobacco crops. In a general framework, this can lead to a more sustainable use of N and can support tobacco breeding programs for NUE.

scholarly journals Variability of nitrogen use efficiency by foxtail millet cultivars at the seedling stage

2020 ◽  
Vol 55 ◽  
Author(s):  
Chen Erying ◽  
Qin Ling ◽  
Yang Yanbing ◽  
Zhang Huawen ◽  
Wang Hailian ◽  
...  
Keyword(s):  
N Uptake ◽  
Foxtail Millet ◽  
Seedling Stage ◽  
Utilization Efficiency ◽  
N Use Efficiency ◽  
Shoot Biomass ◽  
Strong Positive Correlation ◽  
N Content ◽  
Use Efficiency ◽  
N Use

Abstract: The objective of this work was to identify the genetic variation of foxtail millet (Setaria italica) cultivars, from three ecogeographic origins in China, regarding the uptake and utilization of N by the genotypes at the seedling stage, aiming at the genetic improvement of this crop. Seedlings of 79 cultivars were fertilized with a nutrient solution, on a sand substrate, and evaluated under low-N (LN, 0.2 mmol L-1) and high-N (HN, 6.0 mmol L-1) concentrations. A large variation was observed between cultivars, among the three ecogeographic regions, for shoot biomass, shoot N content and concentration, and N use efficiency (NUE), uptake efficiency (NupE), and utilization efficiency (NutE), especially under HN conditions. Cultivars of Northwest China showed the highest variation for shoot biomass, N content, NUE, and NupE. A strong positive correlation was observed between NUE and NupE, and NUE and NutE, but there was no correlation between NupE and NutE. NupE accounted for 77.6% of the total variation of NUE, and NutE for the rest. The uptake and utilization of N show a large variation among the foxtail millet cultivars at the seedling stage, and the variation of N uptake contributes more than that of N utilization to the variation of N use efficiency.

scholarly journals A STELLA-Based Model to Simultaneously Predict Hydrological Processes, N Uptake and Biomass Production in a Eucalyptus Plantation

Forests ◽  
2021 ◽  
Vol 12 (5) ◽  
pp. 515
Author(s):  
Ying Ouyang ◽  
Gary Feng ◽  
Heidi Renninger ◽  
Theodor D. Leininger ◽  
Prem Parajuli ◽  
...  
Keyword(s):  
Water Use ◽  
Biomass Production ◽  
Net Primary Production ◽  
N Uptake ◽  
Hydrological Processes ◽  
Modeling Tools ◽  
Eucalyptus Plantation ◽  
Simulation Scenario ◽  
Use Efficiency ◽  
N Use

Eucalyptus is one of the fastest growing hardwoods for bioenergy production. Currently, few modeling tools exist to simultaneously estimate soil hydrological processes, nitrogen (N) uptake, and biomass production in a eucalyptus plantation. In this study, a STELLA (Structural Thinking and Experiential Learning Laboratory with Animation)-based model was developed to meet this need. After the model calibration and validation, a simulation scenario was developed to assess eucalyptus (E. grandis × urophylla) annual net primary production (ANPP), woody biomass production (WBP), water use efficiency (WUE), and N use efficiency (NUE) for a simulation period of 20 years. Simulation results showed that a typical annual variation pattern was predicted for water use, N uptake, and ANPP, increasing from spring to fall and decreasing from fall to the following winter. Overall, the average NUE during the growth stage was 700 kg/kg. To produce 1000 kg eucalyptus biomass, it required 114.84 m3 of water and 0.92 kg of N. This study suggests that the STELLA-based model is a useful tool to estimate ANPP, WBP, WUE, and NUE in a eucalyptus plantation.

scholarly journals Improvement of Maize Productivity and N Use Efficiency in a No-Tillage Irrigated Farming System: Effect of Cropping Sequence and Fertilization Management

Plants ◽  
2021 ◽  
Vol 10 (7) ◽  
pp. 1459
Author(s):  
Heba S. A. Salama ◽  
Ali I. Nawar ◽  
Hassan E. Khalil ◽  
Ahmed M. Shaalan
Keyword(s):  
Grain Yield ◽  
Faba Bean ◽  
Farming System ◽  
No Tillage ◽  
Maize Crop ◽  
Egyptian Clover ◽  
Maize Grain Yield ◽  
Use Efficiency ◽  
Maize Grain ◽  
N Use

The sequence of the preceding crops in a no-tillage farming system, could interact with the integrated use of mineral and organic nitrogen (N) sources in a way that improves the growth and productivity of the terminal maize crop, meanwhile, enhancing its N use efficiency (NUE). In the current study, six legume-cereal crop sequences, including faba bean, soybean, Egyptian clover, wheat, and maize were evaluated along two experimental rotations that ended up by planting the terminal maize crop. In addition, the effects of applying variable mineral nitrogen (MN) rates with and without the incorporation of farmyard manure (FYM) on the productive performance of maize and its NUE were tested. The field experiments were conducted in a no-tillage irrigated farming system in Northern Egypt, a location that is characterized by its arid, Mediterranean climate. Results revealed that increasing the legume component in the evaluated crop sequences, up to 75%, resulted in improved maize ear leaf area, 1000-grain weight, and harvest index, thus, a higher final grain yield, with the inclusion of Egyptian clover was slightly better than faba bean. Comparing the crop sequences with 50% legume contribution uncovered the positive effects of soybean preceding crop on the terminal maize crop. Substituting 25% of the applied MN with FYM resulted in similar maize yields to the application of the equivalent 100% MN rates. The fertilizer treatments significantly interacted with the crop sequences in determining the maize grain yield, where the highest legume crop contribution in the crop sequence (75%) equalized the effects of the different fertilizer treatments on maize grain yield. The integrated use of FYM with MN in maize fertilization improved the NUE compared to the application of MN alone. Comparing fertilization treatments with similar MN content, with and without FYM, revealed that the difference in NUE was attributed to the additional amount of FYM. In similar conditions to the current study, it is recommended to grow faba bean two years before maize, while Egyptian clover could be grown directly preceding maize growth, with frequent inclusion of soybean in the sequence, this could be combined with the application of an average of 200 kg MN ha−1 in addition to FYM.

Sign in / Sign up

Export Citation Format

Share Document