Nitrate concentration and accumulation on vegetables related to altitude and sunlight intensity

Abstract Nitrate absorption and concentration in consumed vegetables should be also interrelated with its quality, where it is now less noticed in standard vegetable quality. The higher nitrate content is associated with the human health impact such as the baby blue syndrome and stimulating the tumor growth. The environmental status on especially sunlight intensity and quality has a special role to control nitrate concentration in the leaves. The purpose of this study was to characterize the nitrate concentration and accumulation in Brassica rapa L. grown in an open field and screen shading at lower and medium altitudes. Plant sampling was arranged at lower altitudes under 500 m asl (meters above sea level) and medium altitudes 500-700 m asl. Plant growth under shading and unshaded condition were observed for nitrate status as absorbed and its concentration in the sap plants. The study site at the lower altitude exposed sunlight intensity by 27.2% higher, where it decreased nitrate accumulation by 39.3%. Nitrate accumulation under shaded condition rate of 54.9% exhibited more 17.7% nitrate concentration in the vegetable.

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EC Sensitivity of Hydroponically-Grown Lettuce (Lactuca sativa L.) Types in Terms of Nitrate Accumulation

Agriculture ◽

10.3390/agriculture11040315 ◽

2021 ◽

Vol 11 (4) ◽

pp. 315

Author(s):

Noémi Kappel ◽

Ildikó Fruzsina Boros ◽

Francia Seconde Ravelombola ◽

László Sipos

Keyword(s):

Lactuca Sativa ◽

Nitrate Content ◽

Saline Condition ◽

Fresh Weight ◽

Nitrate Level ◽

Nitrate Accumulation ◽

Strong Negative Correlation ◽

Lactuca Sativa L ◽

Hydroponically Grown ◽

European Markets

The goal of this research was to investigate the effect of electrical conductivity (EC) levels of the nutrient solution on the fresh weight, chlorophyll, and nitrate content of hydroponic-system-grown lettuce. The selected cultivars are the most representative commercial varieties grown for European markets. Seven cultivars (‘Sintia,’ ‘Limeira,’ ‘Corentine,’ ‘Cencibel,’ ‘Kiber,’ ‘Attiraï,’ and ‘Rouxaï’) of three Lactuca sativa L. types’ (butterhead, loose leaf, and oak leaf) were grown in a phytotron in rockwool, meanwhile the EC level of the nutrient solutions were different: normal (<1.3 dS/m) and high (10 dS/m). The plants in the saline condition had a lower yield but elevated chlorophyll content and nitrate level, although the ‘Limeira’ and ‘Cencibel’ cultivars had reduced nitrate levels. The results and the special characteristic of the lollo-type cultivars showed that the nitrate level could be very different due to salinity (‘Limeira’ had the lowest (684 µg/g fresh weight (FW)) and ‘Cencibel’ had the highest (4396 µg/g FW)). There was a moderately strong negative correlation (−0.542) in the reverse ratio among the chlorophyll and nitrate contents in plants treated with a normal EC value, while this relationship was not shown in the saline condition. Under the saline condition, cultivars acted differently, and all examined cultivars stayed under the permitted total nitrate level (5000 µg/g FW).

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Study of nitrate levels in fruits and vegetables to assess the potential health risks in Bangladesh

Scientific Reports ◽

10.1038/s41598-021-84032-z ◽

2021 ◽

Vol 11 (1) ◽

Author(s):

Rayhan Uddin ◽

Mostak Uddin Thakur ◽

Mohammad Zia Uddin ◽

G. M. Rabiul Islam

Keyword(s):

Cluster Analysis ◽

Health Risks ◽

Fruits And Vegetables ◽

Risk Index ◽

Daily Intake ◽

Point Estimate ◽

Nitrate Content ◽

Nitrate Accumulation ◽

Health Risk Index ◽

Potential Health

AbstractNitrate is a chemical compound naturally present in fruits and vegetables. This study aims at assessing the nitrate levels and health risks arising from high consumption of fruits and vegetables in Bangladesh. Sixteen species of fruits and vegetables were examined for nitrates using High-Performance Liquid Chromatography with Photo Diode Array (PDA) detector. Ward’s hierarchical cluster analysis was carried out to identify the cluster of tested fruits and vegetables for the nitrate contents. A point estimate of the daily intake was applied to find the health risks that arise due to elevated levels of nitrate in fruits and vegetables. The results show that root and tuber vegetables accumulate significantly higher levels of nitrate in comparison to fruits and fruit vegetables (P < 0.05). In cluster analysis, the nitrate accumulation of fruits and vegetables show four clear clusters contributing to 29.54%, 7.17%, 4.42%, and 58.57% of the total nitrate content in the entire sample. The risk assessment of the Estimated Daily Intake (EDI) and Health Risk Index (HRI) of almost all the tested samples was in the acceptable range, except for radish, thereby indicating the acceptance of risk due to nitrate intake in Bangladesh. As nitrate may have had risk factor for health, during cultivation and storing the product should be properly monitored.

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Nitrate Accumulation in Relation to Molybdenum Deficiency Leaf Scorch Symptoms

Australian Journal of Biological Sciences ◽

10.1071/bi9600104 ◽

1960 ◽

Vol 13 (1) ◽

pp. 104

Author(s):

LF Notley ◽

GL Wilson

Keyword(s):

Leaf Tissue ◽

Nitrate Content ◽

Nitrate Accumulation ◽

Leaf Scorch ◽

Quantitative Studies ◽

The Relationship

The accumulation of nitrate in the leaf tissue of nitrate-supplied, molybdenumdeficient plants has been suspected as a cause of the scorching symptoms which frequently develop (e.g. Agarwala 1952; Agarwala and Hewitt 1952; Hewitt and McCready 1953). Quantitative studies of the relationship between nitrate content and the symptoms have, however, been inconclusive. The literature suggests (cf. Wilson and Waring 1948; Johnson, Pearson, and Stout 1952) that this may follow from the estimation of nitrate in whole leaf tissue rather than in damaged portions.

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Difference between Burley Tobacco and Flue-Cured Tobacco in Nitrate Accumulation and Chemical Regulation of Nitrate and TSNA Contents

Journal of Chemistry ◽

10.1155/2017/4357456 ◽

2017 ◽

Vol 2017 ◽

pp. 1-13 ◽

Cited By ~ 1

Author(s):

Yafei Li ◽

Hongzhi Shi ◽

Huijuan Yang ◽

Jun Zhou ◽

Jing Wang ◽

...

Keyword(s):

Nitrate Reductase Activity ◽

Reductase Activity ◽

Growth Period ◽

Fast Growth ◽

Nitrate Content ◽

Maturity Stage ◽

Nitrate Accumulation ◽

Burley Tobacco ◽

Tobacco Specific Nitrosamines ◽

Growth Experiments

Tobacco-specific nitrosamines (TSNAs) are harmful carcinogens, with nitrate as a precursor of their formation. Nitrate content is considerably higher in burley tobacco than in flue-cured tobacco, but little has been reported on the differences between types of nitrate accumulation during development. We explored nitrate accumulation prior to harvest and examined the effects of regulatory substances aimed at decreasing nitrate and TSNA accumulation. In growth experiments, nitrate accumulation in burley and flue-cured tobacco initially increased but then declined with the highest nitrate content observed during a fast-growth period. When treating tobacco crops with molybdenum (Mo) during fast growth, nitrate reductase activity in burley tobacco increased significantly, but the NO3-N content decreased. These treatments also yielded significant reductions in NO3-N and TSNA contents. Therefore, we suggest that treatment with Mo during the fast-growth period and a Mo-Gfo (Mo-glufosinate) combination at the maturity stage is an effective strategy for decreasing nitrate and TSNAs during cultivation.

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A Review of Environment Effects on Nitrate Accumulation in Leafy Vegetables Grown in Controlled Environments

Foods ◽

10.3390/foods9060732 ◽

2020 ◽

Vol 9 (6) ◽

pp. 732

Author(s):

Zhonghua Bian ◽

Yu Wang ◽

Xiaoyan Zhang ◽

Tao Li ◽

Steven Grundy ◽

...

Keyword(s):

Environmental Factors ◽

Molecular Mechanisms ◽

Management Strategies ◽

Leafy Vegetables ◽

Future Research ◽

Nitrate Content ◽

Vegetable Production ◽

Nitrate Accumulation ◽

Potential Threat ◽

Controlled Environments

Excessive accumulation of nitrates in vegetables is a common issue that poses a potential threat to human health. The absorption, translocation, and assimilation of nitrates in vegetables are tightly regulated by the interaction of internal cues (expression of related genes and enzyme activities) and external environmental factors. In addition to global food security, food nutritional quality is recognized as being of strategic importance by most governments and other agencies. Therefore, the identification and development of sustainable, innovative, and inexpensive approaches for increasing vegetable production and concomitantly reducing nitrate concentration are extremely important. Under controlled environmental conditions, optimal fertilizer/nutrient element management and environmental regulation play vital roles in producing vegetables with low nitrate content. In this review, we present some of the recent findings concerning the effects of environmental factors (e.g., light, temperature, and CO2) and fertilizer/nutrient solution management strategies on nitrate reduction in vegetables grown under controlled environments and discuss the possible molecular mechanisms. We also highlight several perspectives for future research to optimize the yield and nutrition quality of leafy vegetables grown in controlled environments.

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Air–snow exchange of nitrate: a modelling approach to investigate physicochemical processes in surface snow at Dome C, Antarctica

Atmospheric Chemistry and Physics ◽

10.5194/acp-16-12531-2016 ◽

2016 ◽

Vol 16 (19) ◽

pp. 12531-12550 ◽

Cited By ~ 11

Author(s):

Josué Bock ◽

Joël Savarino ◽

Ghislain Picard

Keyword(s):

Nitrate Concentration ◽

Bulk Diffusion ◽

Chemical Reactor ◽

Early Spring ◽

Temperature Cycle ◽

Special Role ◽

Physicochemical Processes ◽

Exchange Processes ◽

Surface Snow ◽

Modelling Studies

Abstract. Snowpack is a multiphase (photo)chemical reactor that strongly influences the air composition in polar and snow-covered regions. Snowpack plays a special role in the nitrogen cycle, as it has been shown that nitrate undergoes numerous recycling stages (including photolysis) in the snow before being permanently buried in the ice. However, the current understanding of these physicochemical processes remains very poor. Several modelling studies have attempted to reproduce (photo)chemical reactions inside snow grains, but these have relied on strong assumptions to characterise snow reactive properties, which are not well defined. Air–snow exchange processes such as adsorption, solid-state diffusion, or co-condensation also affect snow chemical composition. Here, we present a physically based model of these processes for nitrate. Using as input a 1-year-long time series of atmospheric nitrate concentration measured at Dome C, Antarctica, our model reproduces with good agreement the nitrate measurements in the surface snow. By investigating the relative importance of the main exchange processes, this study shows that, on the one hand, the combination of bulk diffusion and co-condensation allows a good reproduction of the measurements (correlation coefficient r = 0.95), with a correct amplitude and timing of summer peak concentration of nitrate in snow. During winter, nitrate concentration in surface snow is mainly driven by thermodynamic equilibrium, whilst the peak observed in summer is explained by the kinetic process of co-condensation. On the other hand, the adsorption of nitric acid on the surface of the snow grains, constrained by an already existing parameterisation for the isotherm, fails to fit the observed variations. During winter and spring, the modelled concentration of adsorbed nitrate is respectively 2.5 and 8.3-fold higher than the measured one. A strong diurnal variation driven by the temperature cycle and a peak occurring in early spring are two other major features that do not match the measurements. This study clearly demonstrates that co-condensation is the most important process to explain nitrate incorporation in snow undergoing temperature gradient metamorphism. The parameterisation developed for this process can now be used as a foundation piece in snowpack models to predict the inter-relationship between snow physical evolution and snow nitrate chemistry.

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NITRATE ACCUMULATION IN INTERMEDIATE WHEATGRASS

Canadian Journal of Plant Science ◽

10.4141/cjps68-011 ◽

1968 ◽

Vol 48 (1) ◽

pp. 85-88 ◽

Cited By ~ 8

Author(s):

T. Lawrence ◽

F. G. Warder ◽

R. Ashford

Keyword(s):

N Fertilizer ◽

Nitrate Content ◽

Nitrate Accumulation ◽

Intermediate Wheatgrass ◽

Agropyron Intermedium ◽

Fertilizer Rates

The effects of six rates of N fertilizer and five frequencies of clipping on the nitrate content of forage from intermediate wheatgrass, Agropyron intermedium (Host.) Beauv., were studied throughout the 1965 growing season.The nitrate content of the forage increased with increasing rates of N fertilizer, and varied with date of harvest. Toxic levels of nitrates (> 2,000 ppm) were found during the period June 5 to July 17 in samples harvested from grass which had been fertilized with 300 and 375 kg/ha of N fertilizer in the spring. Toxic levels were not found in samples from grass fertilized at lower rates. There was an interaction between frequency of clipping and fertilizer rates. At low fertilizer rates the nitrate content of the forage increased as the frequency of clipping was increased, but at the 375-kg/ha rate of fertilizer the opposite was true.It is suggested that fertilizer rates’ in excess of 225 kg/ha N (200 lb/ac N) may result in toxic levels of nitrate in intermediate wheatgrass.

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Estimation of soil nitrate in the spring as a basis for adjustment of nitrogen fertiliser rates

Agricultural and Food Science ◽

10.23986/afsci.5648 ◽

2000 ◽

Vol 9 (1) ◽

pp. 71-77 ◽

Cited By ~ 4

Author(s):

J. SIPPOLA

Keyword(s):

Root Zone ◽

Nitrate Concentration ◽

Small Deviation ◽

Coefficient Of Determination ◽

Nitrate Content ◽

Maximum Deviation ◽

Soil Nitrate ◽

Mean Values ◽

Nitrogen Fertiliser ◽

The Mean

The performance of SOILN model, which simulates soil nitrogen dynamics, was evaluated in respect to its ability to predict nitrate content in soil in spring when growing barley. The data obtained in three year nitrogen fertiliser experiments on different soil types was used. Model was parametrised using the data of the first experimental year and validation results obtained in following years are presented. The results of the simulations of the springtime nitrate in the root zone showed a reasonably small deviation from the measured values. The coefficient of determination, R2 = 0.56 was significant. The regression equation was y = 4 + 0.66x where the constant term was not significantly different from zero and the slope deviated from zero. The mean value of measured nitrate in the root zone in spring was 16 kg/ha and that from the simulation was 15 kg/ha showing that the mean values were close to each other. The mean of deviations between measured and simulated values was 4 kg/ha and the maximum deviation 9 kg/ha. It is concluded that simulation estimated springtime soil nitrate concentration with reasonable confidence that further testing of estimating soil nitrate concentration in spring for adjustment of nitrogen fertilisation using SOILN model should be continued.;

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Effect of salt and water stresses on growth, nitrogen and phosphorus metabolism in Cucumis sativus L. seedlings

Acta Societatis Botanicorum Poloniae ◽

10.5586/asbp.2008.003 ◽

2011 ◽

Vol 77 (1) ◽

pp. 27-33 ◽

Cited By ~ 1

Author(s):

Elżbieta Sacała ◽

Edward Grzyś ◽

Anna Demczuk ◽

Zofia Spiak

Keyword(s):

Salt Stress ◽

Osmotic Stress ◽

Cucumis Sativus ◽

Nitrate Concentration ◽

Dry Weight ◽

Stress Factors ◽

Fresh Mass ◽

Nitrate Content ◽

Cucumber Seedlings ◽

Nr Activity

Plants exposed to osmotic stress exhibit changes in their physiology and metabolism. In general, osmotic stress reduces water availability and causes nutritional imbalance in plants. In the present study, we compared the response of cucumber (<em>Cucumis sativus</em> L. var. Władko F-1) to ionic (100 mmol•dm-3 NaCl) and osmotic stress (10% PEG 6000). Both stress factors reduced significantly fresh and dry weight of 7-day-old cucumber seedlings. Under PEG treatment reduction of cucumber dry mass was lesser than in fresh mass, whereas under salt stress decrease in dry weight of cucumber shoots was more pronounced than in fresh mass. Salt stress caused severe decrease in nitrate concentration and activity of nitrate reductase (NR). In cotyledons nitrate content declined to 17% of the control and similar reduction in NR activity was observed. In the roots, observed changes were not so drastic but there was also strong interaction between reduction in nitrate content and NR activity. Under 10% PEG both nitrate concentration and NR activity in cucumber roots were significantly higher in comparison to control plants. In cotyledons NR activity was significantly lower than in control plants, while decrease in nitrate content was not statistically significant. Phosphate concentration did not change significantly in cucumber cotyledons but increased in roots treated both NaCl (32% increase) and PEG (53% increase). Similar tendencies were observed in acid phosphatase activity. Obtained results indicated that osmotic and salt stresses evoke differential responses, particularly in growth reduction and nitrogen metabolism in cucumber seedlings.

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In situ Biological Groundwater Denitrification: Concepts and Preliminary Field Tests

Water Science & Technology ◽

10.2166/wst.1988.0099 ◽

1988 ◽

Vol 20 (3) ◽

pp. 197-209 ◽

Cited By ~ 32

Author(s):

A. Mercado ◽

M. Libhaber ◽

M. I. M. Soares

Keyword(s):

Nitrate Concentration ◽

Nitrate Removal ◽

Small Diameter ◽

Field Tests ◽

Economic Feasibility ◽

Injection Well ◽

Nitrate Content ◽

Injection Wells ◽

Protection Measures

High nitrate concentration presents the main groundwater quality problem of the Israeli coastal aquifer which supplies 25% of the total water consumption of the country. In about 50% of the coastal wells nitrate concentration exceeds 45 mg/l and in 18% of the wells nitrate concentration is above the maximum permissible concentration of the new Israeli standard - 70 mg/l. Although several protection measures, mainly administrative, were introduced, their impact would be pronounced only after 1-3 decades, thus nitrate removal technologies should be introduced as a mid-term solution. Pilot plant experiments were conducted in order to develop, demonstrate and compare various in-situ schemes for nitrate removal from groundwater by biological denitrification. Activities were focused towards two schemes: (i) Denitrification in a dual purpose (recharge-pumping) well and (ii) Substrate injection through a battery of small diameter wells surrounding a central production well (the “Daisy” system). Experiments related to the first scheme indicate that, though nitrate content can be reduced almost to zero, its economic feasibility seems to be unfavorable because of operational difficulties and the apparent requirements for costly supplementary treatment. Experiments related to the “Daisy” scheme demonstrated a nitrate removal efficiency of approximately 10%. Considering the fact that only one injection well of the three drilled functioned properly, the above mentioned nitrate removal represents the efficiency of a single injection well. It is anticipated that further experiments with the “Daisy” system consisting of 5-6 injection wells would result in a significant nitrate reduction.

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