The Arabidopsis Nitrate Transporter NRT1.8 Functions in Nitrate Removal from the Xylem Sap and Mediates Cadmium Tolerance

The study tested the hypothesis that substitution of nitrate supply with other anions induces the mobilization of stored nitrate in broccoli (Brassica oleracea var. italica) plants. Broccoli plants, grown under greenhouse conditions in soilless culture, were provided with either a continuous supply of nitrate in the nutrient solution until commercial maturity, or with a nitrate supply only up to inflorescence emergence. At inflorescence emergence, nitrate was also substituted with various chloride or sulphate salts of sodium, potassium and ammonium (15 and 5 mmol L−1). During the period of inflorescence development studied, plant size increased by two- to threefold. Nitrate removal or its substitution with chloride or sulphate salts of sodium and potassium (15 mmol L−1) resulted in 13% less dry-matter accumulation and 63–97% less xylem-sap nitrate than continuous nitrate supply, and 57–62% decline in the plant-nitrate content found at inflorescence emergence. In contrast, chloride or sulphate salts of ammonium (5 mmol L−1) sustained plant growth, while also decreasing xylem-sap nitrate by 83–90% and plant-nitrate content by 58–62%. Phloem-exudate nitrate of plants receiving nitrate continuously was only 7% of that of xylem sap, and was decreased by 63% by an interrupted nitrate supply. Therefore, the removal of nitrate and substitution with a low supply of ammonium, rather than other anions, is recommended for decreasing plant-nitrate content. Key words: Broccoli, chloride, mobilization, nitrate, sulphate

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EQUILIBRIUM AND KINETICS STUDY OF NITRATE REMOVAL FROM WATER BY PUROLITE A520-E RESIN

Environmental Engineering and Management Journal ◽

10.30638/eemj.2012.006 ◽

2012 ◽

Vol 11 (1) ◽

pp. 37-45 ◽

Cited By ~ 4

Author(s):

Liliana Lazar ◽

Laura Bulgariu ◽

Anca Ceica ◽

Igor Cretescu ◽

Ion Balasanian

Keyword(s):

Nitrate Removal ◽

Kinetics Study ◽

Equilibrium And Kinetics

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Water conditioning equipment inside buildings. Nitrate removal devices. Requirements for performance, safety and testing

10.3403/30132379 ◽

2007 ◽

Keyword(s):

Nitrate Removal ◽

Water Conditioning ◽

Conditioning Equipment

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Faculty Opinions recommendation of The nitrate transporter AtNRT1.1 (CHL1) functions in stomatal opening and contributes to drought susceptibility in Arabidopsis.

Faculty Opinions – Post-Publication Peer Review of the Biomedical Literature ◽

10.3410/f.1011130.182178 ◽

2003 ◽

Author(s):

Jocelyn Malamy

Keyword(s):

Stomatal Opening ◽

Nitrate Transporter

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Optimal operations for groundwater denitrification of drinking water using heterotrophic biological denitrification process

Water Science & Technology Water Supply ◽

10.2166/ws.2006.060 ◽

2006 ◽

Vol 6 (2) ◽

pp. 125-130

Author(s):

C.-H. Hung ◽

K.-H. Tsai ◽

Y.-K. Su ◽

C.-M. Liang ◽

M.-H. Su ◽

...

Keyword(s):

Drinking Water ◽

Removal Efficiency ◽

Nitrate Removal ◽

Drinking Water Treatment ◽

Nitrate Content ◽

Source Water ◽

Nitrogen Gas ◽

Negative Effect ◽

Denitrification Process ◽

Heterotrophic Denitrification

Due to the extensive application of artificial nitrogen-based fertilizers on land, groundwater from the central part of Taiwan faces problems of increasing concentrations of nitrate, which were measured to be well above 30 mg/L all year round. For meeting the 10 mg/L nitrate standard, optimal operations for a heterotrophic denitrification pilot plant designed for drinking water treatment was investigated. Ethanol and phosphate were added for bacteria growing on anthracite to convert nitrate to nitrogen gas. Results showed that presence of high dissolved oxygen (around 4 mg/L) in the source water did not have a significantly negative effect on nitrogen removal. When operated under a C/N ratio of 1.88, which was recommended in the literature, nitrate removal efficiency was measured to be around 70%, sometimes up to 90%. However, the reactor often underwent severe clogging problems. When operated under C/N ratio of 1.0, denitrification efficiency decreased significantly to 30%. Finally, when operated under C/N ratio of 1.5, the nitrate content of the influent was almost completely reduced at the first one-third part of the bioreactor with an overall removal efficiency of 89–91%. Another advantage for operating with a C/N ratio of 1.5 is that only one-third of the biosolids was produced compared to a C/N value of 1.88.

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