Effects of elevated ozone and nitrogen addition on leaf nitrogen metabolism in poplar

2021 ◽  
Author(s):  
Bo Shang ◽  
Zhaozhong Feng ◽  
Jinlong Peng ◽  
Yansen Xu ◽  
Elena Paoletti
Keyword(s):  
Ambient Air ◽  
N Deposition ◽  
Interactive Effects ◽  
Total Soluble Protein ◽  
Total Amino Acid ◽  
N Content ◽  
Total N ◽  
N Metabolism ◽  
N Treatment ◽  
Leaf N

Abstract Aims Ozone (O3) pollution and nitrogen (N) deposition/fertilization often simultaneously affect plant growth. However, research of their interactive effects on leaf N metabolism is still scarce. We investigated their interactive effects, aiming to better understand plant N metabolism processes and biogeochemical cycles under high O3 pollution and N deposition/fertilization. Methods Poplar saplings were exposed to two O3 levels (NF, non-filtered ambient air; NF60, NF + 60 ppb O3) and four N treatments (N0, no N added; N50, N0 + 50 kg N ha -1 yr -1; N100, N0 + 100 kg N ha -1 yr -1; N200, N0 + 200 kg N ha -1 yr -1) in open-top chambers for 95 days. The indicators related to leaf N metabolism were analyzed, including the activities of N-metabolizing enzymes and the contents of total N, NO3  --N, NH4  +-N, total amino acid (TAA) and total soluble protein (TSP) in the leaves. Important Findings NF60 stimulated the activities of nitrate reductase (NR) by 47.2% at August relative to NF, and stimulated glutamine synthetase (GS) by 57.3% when averaged across all N treatments and sampling times. In contrast, O3 did not significantly affect TSP and even reduced TAA content in August. Relative to N0, N200 significantly increased light-saturated rate of CO2 assimilation (Asat) by 24%, and increased total N content by 70.3% and 43.3% in August and September, respectively, while it reduced photosynthetic N-use efficiency by 26.1% in August. These results suggest that the increase in Asat and total N content are uncoupled, and that the surplus N is not used to optimize the capacity for carbon assimilation under high N treatment. Simultaneously, high N treatment significantly promoted leaf N metabolism by increasing NO3 --N contents, NH4 +-N contents, TAA contents and the activities of NR and GS. There was no significant interaction between O3 and N for all variables.

Variability in physiological responses of Venezuelan cacao to drought

2020 ◽  
Vol 56 (3) ◽  
pp. 407-421 ◽  
Author(s):  
Wilmer Tezara ◽  
Gabriela Pereyra ◽  
Eleinis Ávila-Lovera ◽  
Ana Herrera
Keyword(s):  
Chlorophyll Content ◽  
Water Use ◽  
Isotopic Ratio ◽  
Water Status ◽  
Common Garden ◽  
Photochemical Activity ◽  
Total Soluble Protein ◽  
N Content ◽  
Leaf N Content ◽  
Leaf N

AbstractIn order to assess the response of cocoa trees to drought, changes in water status, gas exchange, leaf carbon isotopic ratio (δ13C), photochemical activity, and leaf N and chlorophyll content during the rainy and dry season were measured in 31 Venezuelan cocoa clones (17 Trinitarios, 6 Criollos, and 8 Modern Criollos) grown in a common garden. Drought caused a 40% decrease in water potential (ψ) in all but the Modern Criollos, and a reduction in net photosynthetic rate (A) and stomatal conductance (gs) without an increase in instantaneous water use efficiency (WUE) in 93% of clones, and an increase in δ13C (long-term WUE) in 74% of clones; these responses suggest differences in tolerance to drought among clones. A positive correlation between A and both gs and leaf N content was found for all genotypes. Leaf N content, chlorophyll content, and photochemical activity were reduced during drought, suggesting that metabolism was also inhibited. The best performance during drought was shown by Modern Criollos with the highest WUE, while five Trinitario clones seemed to be less sensitive to drought, since neither chlorophyll, N, total soluble protein concentration, nor gs changed with drought, indicating that those Trinitario clones, with lower A, have a conservative water use. Modern Criollos showed no reductions in either ψ or gs; A remained unchanged, as did WUE, which was the highest, suggesting that these clones would be more successful in environments with low water availability. Our results indicate large variation in physiological response to drought over a range of parameters, suggesting possible differences in tolerance among clones.

scholarly journals Long-term ecosystem nitrogen limitation from foliar δ15N data and a land surface model

2021 ◽  
Author(s):  
Silvia Caldararu ◽  
Tea Thum ◽  
Lin Yu ◽  
Melanie Kern ◽  
Richard Nair ◽  
...  
Keyword(s):  
Land Surface ◽  
Nitrogen Limitation ◽  
Land Surface Model ◽  
N Deposition ◽  
Spatial And Temporal Variation ◽  
Surface Model ◽  
Terrestrial Carbon ◽  
N Content ◽  
N Limitation ◽  
Leaf N

The effect of nutrient availability on plant growth and the terrestrial carbon sink under climate change and elevated CO2 remains one of the main uncertainties of the terrestrial carbon cycle. This is partially due to the difficulty of assessing nutrient limitation at large scales over long periods of time. Consistent declines in leaf nitrogen (N) content and leaf δ15N have been used to suggest that nitrogen limitation has increased in recent decades, most likely due to the concurrent increase in atmospheric CO2. However, such datasets are often not straightforward to interpret due to the complex factors that contribute to the spatial and temporal variation in leaf N and isotope concentration. We use the land surface model QUINCY, which has the unique capacity to represent N isotopic processes, in conjunction with two large datasets of foliar N and N isotope content. We run the model with different scenarios to test whether foliar δ15N isotopic data can be used to infer large scale nitrogen limitation and if the observed trends are caused by increasing atmospheric CO2, changes in climate or changes in sources of anthropogenic N deposition. We show that while the model can capture the observed change in leaf N content and predicts widespread increases in N limitation, it does not capture the pronounced, but very spatially heterogeneous, decrease in foliar δ15N observed in the data across the globe. The addition of an observed temporal trend in isotopic composition of N deposition leads to a more pronounced decrease in simulated leaf δ15N. Our results show that leaf δ15N observations should not, on their own, be used to assess global scale N limitation and that using such a dataset in conjunction with a land surface model can reveal the drivers behind the observed patterns.

scholarly journals Nitrogen availability effects on gas exchange measurements in field-grown maize (Zea mays L.) under irrigated Mediterranean conditions

2016 ◽  
Vol 14 (4) ◽  
pp. e0806 ◽  
Author(s):  
Ramón Isla ◽  
Mónica Guillén ◽  
Montserrat Salmerón
Keyword(s):  
Gas Exchange ◽  
Grain Yield ◽  
N Availability ◽  
Mineral N ◽  
N Content ◽  
Total N ◽  
Available N ◽  
N Supply ◽  
Different Levels ◽  
Leaf N

There are limited studies about the effect of nitrogen (N) deficiency on leaf growth, N status, and photosynthetic capacity of maize grown under field conditions in a Mediterranean climate. The objective of this work was to evaluate the effect of different levels of mineral N availability on leaf gas exchange parameters of sprinkler irrigated maize. The experiment was conducted in a conventional maize field located in the central part of the Ebro valley (Spain) during two seasons. Using a portable LICOR-6400 equipment, instantaneous measurements and light response curves to gas exchange were conducted in plots with different levels of N supply ranging from deficient (no fertilized) to over-fertilized (300 kg N/ha). In addition to gas exchange measurements, mineral soil N content, chlorophyll meter readings (CMR), leaf N content, and grain yield were measured in the different plots. Results showed that grain yield reached a plateau (14.5 Mg/ha) when the mineral N available was about 179 kg/ha. CMR were linearly and highly related to total N in ear leaves. The relationship between light-saturated leaf photosynthesis measurements and CMR was significant but very weak (R2=0.13) at V8 and V14 stages but increased later in the growing season (R2=0.52). Plants with intermediate levels of N supply (48<CMR<54) tended to have slightly higher assimilation rates than plants with higher CMR readings. As the available N increased, the saturation point, the light compensation point and significant increases of dark respiration rate were observed. Under the conditions of the study, leaf N contents of 1.9% in the ear leaf were enough to maximize leaf assimilation rates with no need to over-fertilize the maize crop.

scholarly journals Uptake, Partitioning, and Storage of Fertilizer Nitrogen in Red Raspberry as Affected by Rate and Timing of Application

2004 ◽  
Vol 129 (3) ◽  
pp. 439-448 ◽  
Author(s):  
Hannah G. Rempel ◽  
Bernadine C. Strik ◽  
Timothy L. Righetti
Keyword(s):  
N Uptake ◽  
Dry Weight ◽  
Rubus Idaeus ◽  
Split Application ◽  
Fertilizer N ◽  
Red Raspberry ◽  
N Content ◽  
Total N ◽  
N Treatment ◽  
Fruit Harvest

The effects of 15N-labeled fertilizer applied to mature summer-bearing red raspberry (Rubus idaeus L. `Meeker') plants were measured over 2 years. Four nitrogen (N) treatments were applied: singularly at 0, 40, or 80 kg·ha-1 of N in early spring (budbreak), or split with 40 kg·ha-1 of N (unlabeled) applied at budbreak and 40 kg·ha-1 of N (15N-depleted) applied eight weeks later. Plants were sampled six times per year to determine N and 15N content in the plant components throughout the growing season. Soil also was sampled seven times per year to determine inorganic N concentrations within the four treatments as well as in a bare soil plot. There was a tendency for the unfertilized treatment to have the lowest and for the split-N treatment to have the highest yield in both years. N application had no significant effect on plant dry weight or total N content in either year. Dry weight accumulation was 5.5 t·ha-1 and total N accumulation was 88 to 96 kg·ha-1 for aboveground biomass in the fertilized plots in 2001. Of the total N present, averaged over 2 years, 17% was removed in prunings, 12% was lost through primocane leaf senescence, 13% was removed through fruit harvest, 30% remained in the over-wintering plant, and 28% was considered lost or transported to the roots. Peak fertilizer N-uptake occurred by July for the single N applications and by September for the last application in the split-N treatment. This uptake accounted for 36% to 37% (single applications) and 24% (last half of split application) of the 15N applied. Plants receiving the highest single rate of fertilizer took up more fertilizer N while plants receiving the lower rate took up more N from the soil and from storage tissues. By midharvest, fertilizer N was found primarily in the fruit, fruiting laterals, and primocanes (94%) for all fertilized treatments; however, the majority of the fertilizer N applied in the last half of the split application was located in the primocanes (60%). Stored fertilizer N distribution was similar in all fertilized treatments. By the end of the second year, 5% to 12% of the fertilizer acquired in 2001 remained in the fertilized plants. Soil nitrate concentrations increased after fertilization to 78.5 g·m-3, and declined to an average of 35.6 g·m-3 by fruit harvest. Seasonal soil N decline was partially attributed to plant uptake; however, leaching and immobilization into the organic fraction may also have contributed to the decline.

scholarly journals COVER CROPS AND NITROGEN FERTILIZATION - NUTRITIONAL ASPECTS AND AGRONOMIC PERFORMANCE OF MAIZE GROWN IN SUCESSION

2020 ◽  
Vol 19 ◽  
pp. 16
Author(s):  
ROMANO ROBERTO VALICHESKI ◽  
JORDANO GILBERTO EGER ◽  
SIDINEI LEANDRO K. STÜRMER ◽  
FABRÍCIO FLÁVIO AMLER ◽  
FELIPE JOSÉ ESTEVÃO ◽  
...  
Keyword(s):  
Cover Crops ◽  
Total Protein Content ◽  
Plant Analysis ◽  
Nitrogen Use ◽  
Agronomic Efficiency ◽  
N Content ◽  
Total N ◽  
Average Value ◽  
Leaf N Content ◽  
Leaf N

Cover crops can contribute differently to the supply of nitrogen to crops. The objective was to evaluate the response of maize to nitrogen doses (0, 70, 140, 210 and 280 kg ha-1) when grown in succession to cover crops (vetch, forage turnip, black oat, ryegrass and fallow). The randomized block experimental design was used, with subdivided plots and four replications. Cover crops were allocated into plots, and N doses into sub-plots. As to cover crops, the aspects evaluated were phytomass production, N content and total accumulated; with regard to maize, the aspects evaluated were SPAD (Soil Plant Analysis  evelopment) index, leaf N content, total grain protein, yield and agronomic efficiency of N. Black oat, ryegrass and forage turnip presented higher phytomass production. All species had similar results as to the total N accumulated in the aerial part (average value of 91.06 kg ha-1). In succession to black oat, ryegrass and fallow period, N doses up to 140 kg ha-1 applied in maize result in higher yield and better agronomic efficiency of nitrogen use. Without application of nitrogen (0.0 kg ha1), forage turnip and vetch provided higher total protein content in the grain, yield over 8,550 kg ha-1, and less agronomic efficiency of nitrogen use.

scholarly journals Increased Grain Amino Acid Content in Rice with Earthworm Castings

2019 ◽  
Vol 9 (6) ◽  
pp. 1090 ◽  
Author(s):  
Min Huang ◽  
Chunrong Zhao ◽  
Yingbin Zou
Keyword(s):  
Amino Acid ◽  
Acid Content ◽  
Nutritional Value ◽  
Acid Metabolism ◽  
Amino Acid Content ◽  
Total Amino Acid ◽  
N Content ◽  
Total N ◽  
Rice Grains ◽  
Total Amino Acid Content

Enhancing the nutritional value of rice can improve the health of rice consumers. Grain amino acid content is an important nutritional component. This study was conducted to test the hypothesis that the application of earthworm castings could increase the grain amino acid content in rice. Results showed that total amino acid content in the grain of rice was significantly elevated by applying earthworm castings (17 kg m−2), with an average increase of 8% across four tested rice cultivars. Application of earthworm castings had no significant effect on total nitrogen (N) content but significantly increased the ratio of amino acid to N (total amino acid content/total N content) in rice grains. The results of the present study suggest that application of earthworm castings can increase grain amino acid content in rice by improving the efficiency of the N to amino acid conversion, and highlight that further studies are required to assess the effects of earthworm castings on the amino acid metabolism in rice grains.

scholarly journals Yield and N use efficiency of wheat as influenced by bed planting and N application

1970 ◽  
Vol 33 (3) ◽  
pp. 439-448 ◽  
Author(s):  
MA Khaleque ◽  
NK Paul ◽  
Craig A Meisner
Keyword(s):  
Grain Yield ◽  
N Use Efficiency ◽  
N Content ◽  
Total N ◽  
Recovery Percentage ◽  
Use Efficiency ◽  
N Treatment ◽  
Fertilizer Recovery ◽  
N Use ◽  
Planting System

Wheat (Triticum aestivum L.) was planted as winter crop using raised bed and conventional planting system with four N levels at Regional Wheat Research Station, Rajshahi (latitude 28°75′ N and longitude 92°58′ E), during November to March in 2002 and 2003 to study N content in grain and straw, uptake of total nitrogen, N use efficiency, fertilizer recovery percentage and grain yield. The highest N content in grain and straw were obtained from bed planting system with Shatabdi at 150% N treatment. Maximum total N uptake by the plants was found in bed elevation as compared to conventional planting system. The highest N use efficiency was observed at N zero treatment as compared to applied N levels. Shatabdi noticed highest N use efficiency among the crop varieties. The maximum fertilizer recovery percentage was noted in Shatabdi under bed planting system. The highest grain yield (2,555 kg/ha) was produced from bed planting system. Significantly the highest grain yield (2,929 kg/ha) was found in Shatabdi. The highest grain yield (3,746 kg/ha) was found when 150% N was applied. In bed planting system, the highest grain yield (3,323 kg/ha) was produced when 150% N was applied. The lowest grain yield (1,177 kg/ha) was obtained in zero N treatment. Among the varieties, Shatabdi was the best performer in bed planting system due to maximum nitrogen and protein content in grain and straw, maximum N use efficiency and fertilizer recovery percentage. Key Words: Bed planting, N content, N use efficiency and fertilizer recovery percentage. doi:10.3329/bjar.v33i3.1603 Bangladesh J. Agril. Res. 33(3) : 439-448, September 2008

scholarly journals Implementation of nitrogen cycle in the CLASSIC land model

2020 ◽  
Author(s):  
Ali Asaadi ◽  
Vivek K. Arora
Keyword(s):  
N Deposition ◽  
Atmospheric Co2 ◽  
Historical Period ◽  
N Fixation ◽  
N Content ◽  
N Cycle ◽  
C Cycle ◽  
C And N ◽  
Leaf N Content ◽  
Leaf N

Abstract. A terrestrial nitrogen (N) cycle model is coupled to carbon (C) cycle in the framework of the Canadian Land Surface Scheme Including biogeochemical Cycles (CLASSIC). CLASSIC currently models physical and biogeochemical processes and simulates fluxes of water, energy, and CO2 at the land-atmosphere boundary. Similar to most models, gross primary productivity in CLASSIC increases in response to increasing atmospheric CO2 concentration. In the current model version, a downregulation parameterization emulates the effect of nutrient constraints and scales down potential photosynthesis rates, using a globally constant scalar, as a function of increasing CO2. In the new model when N and C cycles are coupled, cycling of N through the coupled soil-vegetation system facilitates the simulation of leaf N content and maximum carboxylation capacity (Vcmax) prognostically. An increase in atmospheric CO2 decreases leaf N content, and therefore Vcmax, allowing the simulation of photosynthesis downregulation as a function of N supply. All primary N cycle processes, that represent the coupled soil-vegetation system, are modelled explicitly. These include biological N fixation, treatment of externally specified N deposition and fertilization application, uptake of N by plants, transfer of N to litter via litterfall, mineralization, immobilization, nitrification, ammonia volatilization, leaching, and the gaseous fluxes of NO, N2O, and N2. The interactions between terrestrial C and N cycles are evaluated by perturbing the coupled soil-vegetation system in CLASSIC with one forcing at a time over the 1850–2017 historical period. These forcings include the increase in atmospheric CO2, change in climate, increase in N deposition, and increasing crop area and fertilizer input, over the historical period. The model response to these forcings is consistent with conceptual understanding of the coupled C and N cycles. The simulated terrestrial carbon sink over the 1959–2017 period, from the simulation with all forcings, is 2.0 Pg C/yr and compares reasonably well with the quasi observation-based estimate from the 2019 Global Carbon Project (2.1 Pg C/yr). The contribution of increasing CO2, climate change, and N deposition to carbon uptake by land over the historical period (1850–2017) is calculated to be 84 %, 2 %, and 14 %, respectively.

COVER CROPS AND NITROGEN FERTILIZATION - NUTRITIONAL ASPECTS AND AGRONOMIC PERFORMANCE OF MAIZE GROWN IN SUCESSION

2020 ◽  
Vol 19 ◽  
pp. 16
Author(s):  
ROMANO ROBERTO VALICHESKI ◽  
JORDANO GILBERTO EGER ◽  
SIDINEI LEANDRO K. STÜRMER ◽  
FABRÍCIO FLÁVIO AMLER ◽  
FELIPE JOSÉ ESTEVÃO ◽  
...  
Keyword(s):  
Cover Crops ◽  
Total Protein Content ◽  
Plant Analysis ◽  
Nitrogen Use ◽  
Agronomic Efficiency ◽  
N Content ◽  
Total N ◽  
Average Value ◽  
Leaf N Content ◽  
Leaf N

Cover crops can contribute differently to the supply of nitrogen to crops. The objective was to evaluate the response of maize to nitrogen doses (0, 70, 140, 210 and 280 kg ha-1) when grown in succession to cover crops (vetch, forage turnip, black oat, ryegrass and fallow). The randomized block experimental design was used, with subdivided plots and four replications. Cover crops were allocated into plots, and N doses into sub-plots. As to cover crops, the aspects evaluated were phytomass production, N content and total accumulated; with regard to maize, the aspects evaluated were SPAD (Soil Plant Analysis  evelopment) index, leaf N content, total grain protein, yield and agronomic efficiency of N. Black oat, ryegrass and forage turnip presented higher phytomass production. All species had similar results as to the total N accumulated in the aerial part (average value of 91.06 kg ha-1). In succession to black oat, ryegrass and fallow period, N doses up to 140 kg ha-1 applied in maize result in higher yield and better agronomic efficiency of nitrogen use. Without application of nitrogen (0.0 kg ha1), forage turnip and vetch provided higher total protein content in the grain, yield over 8,550 kg ha-1, and less agronomic efficiency of nitrogen use.

scholarly journals A novel approach for nitrogen diagnosis of wheat canopies digital images by mobile phones based on histogram

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Xin Qi ◽  
Yanan Zhao ◽  
Yufang Huang ◽  
Yang Wang ◽  
Wei Qin ◽  
...  
Keyword(s):  
Neural Network ◽  
Mobile Phones ◽  
Mean Value ◽  
Wheat Cultivars ◽  
N Content ◽  
Color Parameters ◽  
The Neural Network ◽  
The Mean ◽  
Leaf N Content ◽  
Leaf N

AbstractThe accurate and nondestructive assessment of leaf nitrogen (N) is very important for N management in winter wheat fields. Mobile phones are now being used as an additional N diagnostic tool. To overcome the drawbacks of traditional digital camera diagnostic methods, a histogram-based method was proposed and compared with the traditional methods. Here, the field N level of six different wheat cultivars was assessed to obtain canopy images, leaf N content, and yield. The stability and accuracy of the index histogram and index mean value of the canopy images in different wheat cultivars were compared based on their correlation with leaf N and yield, following which the best diagnosis and prediction model was selected using the neural network model. The results showed that N application significantly affected the leaf N content and yield of wheat, as well as the hue of the canopy images and plant coverage. Compared with the mean value of the canopy image color parameters, the histogram could reflect both the crop coverage and the overall color information. The histogram thus had a high linear correlation with leaf N content and yield and a relatively stable correlation across different growth stages. Peak b of the histogram changed with the increase in leaf N content during the reviving stage of wheat. The histogram of the canopy image color parameters had a good correlation with leaf N content and yield. Through the neural network training and estimation model, the root mean square error (RMSE) and the mean absolute percentage error (MAPE) of the estimated and measured values of leaf N content and yield were smaller for the index histogram (0.465, 9.65%, and 465.12, 5.5% respectively) than the index mean value of the canopy images (0.526, 12.53% and 593.52, 7.83% respectively), suggesting a good fit for the index histogram image color and robustness in estimating N content and yield. Hence, the use of the histogram model with a smartphone has great potential application in N diagnosis and prediction for wheat and other cereal crops.

Sign in / Sign up

Export Citation Format

Share Document