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Registros recuperados: 59 | |
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ROSALES LOAIZA,Néstor; VERA,Patricia; AIELLO-MAZZARRI,Cateryna; MORALES,Ever. |
Nitrogen concentration is an essential parameter in cyanobacterial cultures to produce enriched biomass with biotechnological purposes. Growth and biochemical composition of Nostoc LAUN0015, Nostoc UAM206, Anabaena sp.1 and Anabaena sp.2 were compared at 0, 4.25, 8.5 and 17 mM NaNO3. Cultures under laboratory conditions were maintained for 30 days at a volume of 500 mL. Anabaena sp.1 yielded the highest value of dry mass of 0.26 ± 2.49 mg mL-1 at 8.5 mM NaNO3. For chlorophyll, phycocyanin and phycoerythrin, maximum values were achieved at 17 mM NaNO3 with 18.09 ± 1.74, 102.90 ± 6.73 and 53.47 ± 2.40 μg mL-1, respectively. Nostoc LAUN0015 produced its maximum value of protein 644.86 ± 19.77 μg mL-1, and 890 mg mL-1 of carbohydrates in the absence of... |
Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Anabaena; Biochemical composition; Biomass; Culture; Nitrate; Nostoc. |
Ano: 2016 |
URL: http://www.scielo.org.co/scielo.php?script=sci_arttext&pid=S0120-548X2016000200003 |
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Gaiad,Sérgio; Rakocevic,Miroslava; Reissmann,Carlos Bruno. |
The influence of different N sources on the growth of maté (Ilex paragurariensis St.Hil.) seedlings grown in greenhouse was studied. All seedlings received a base fertilization of 10 mg N.kg-1 soil as NH4NO3, 60 mg P2O5.and 40 mg K2O.kg-1 soil as KH2PO4 15 days before treatments application. Treatments were as follow: Control, with no extra N added; Urea = 100 mg N.kg-1 soil as Urea; NO3- = 100 mg N.kg-1 soil as Ca(NO3)2; and NH4+ = 100 mg N.kg-1 soil as (NH4)2SO4. It was concluded that: 1) increasing N content in leaves alone was not able to promote gain in biomass production of maté seedlings; 2) seedlings receiving N-NH4 showed a higher accumulation of P and Mg on shoot biomass; and 3) an increase in leaf area, leaf number and net photosynthesis... |
Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Ammonium; Nitrate; Soil pH. |
Ano: 2006 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1516-89132006000600001 |
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Moriel,P.; Sevanian,A.; Ajzen,S.; Zanella,M.T.; Plavnik,F.L.; Rubbo,H.; Abdalla,D.S.P.. |
The objective of the present study was to identify disturbances of nitric oxide radical (·NO) metabolism and the formation of cholesterol oxidation products in human essential hypertension. The concentrations of·NO derivatives (nitrite, nitrate, S-nitrosothiols and nitrotyrosine), water and lipid-soluble antioxidants and cholesterol oxides were measured in plasma of 11 patients with mild essential hypertension (H: 57.8 ± 9.7 years; blood pressure, 148.3 ± 24.8/90.8 ± 10.2 mmHg) and in 11 healthy subjects (N: 48.4 ± 7.0 years; blood pressure, 119.4 ± 9.4/75.0 ± 8.0 mmHg).Nitrite, nitrate and S-nitrosothiols were measured by chemiluminescence and nitrotyrosine was determined by ELISA. Antioxidants were determined by reverse-phase HPLC and cholesterol oxides... |
Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Nitrotyrosine; S-nitrosothiols; Nitrate; Oxidized LDL; Lipid peroxidation; Endothelin-1. |
Ano: 2002 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0100-879X2002001100007 |
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Garbin,Mário L.; Dillenburg,Lúcia R.. |
The southern Brazilian highland plateau is a mosaic of two contrasting plant communities, Araucaria forests and grasslands, which differ in the relative abundances and spatial patterns of soil nitrate and ammonium. However, we still do not know the inorganic N preferences of one key species in this mosaic, Araucaria angustifolia, the dominant tree species in the Araucaria forests and an important tree species invading the adjacent grasslands. Growth responses measured in a greenhouse study demonstrated that the species prefers NH4+ over NO3- as an inorganic N source. When provided alone, NO3- induced N deficiency symptoms: increases in root: shoot ratio, root branching and leaf mass per area, thickening of the shoot apexes and decreased mass-based... |
Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Araucariaceae; Ammonium; Inorganic nitrogen; Nitrate; Nitrogen deficiency. |
Ano: 2008 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1677-04202008000400005 |
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Núñez,Pedro A.; Demanet,Rolando; Misselbrook,Tom H.; Alfaro,Marta; Mora,María de la Luz. |
Chilean livestock production systems have intensified over the last years, with increasing amounts of N fertilizer inputs creating the potentiality for environmental damage through N pollution of water and air, so that alternative production strategies have been developed to reduce such environmental impacts. This study assesses N losses under different grazing frequencies and intensities on permanent pasture (Lolium perenne L., Festuca arundinacea Schreb., Dactylis glomerata L., and Trifolium repens L.) on an Andisol in Southern Chile. Four grazing strategies were evaluated: frequent-heavy (FH), frequent-light (FL), infrequent-heavy (IH), infrequent-light (IL), and a no grazing control (C) treatment, and each with three replicates in a randomized complete... |
Tipo: Journal article |
Palavras-chave: Ammonium; Grazing; Leaching; Nitrate; NH3 volatilization. |
Ano: 2010 |
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0718-58392010000200007 |
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Escobar,Hugo; Bustos,Richard; Fernández,Felipe; Cárcamo,Henry; Silva,Herman; Frank,Nicolás; Cardemil,Liliana. |
We analyzed the mitigating effect of NO3 - and salicylic acid (SA) on the detrimental effects of salt stress by studying the water status of plants of maize grown in Hoagland's medium with NaCl 100 mM as the saline component, to which SA and NO3 - were added in different concentrations as mitigating agents. We evaluated water potential Ψw, osmotic potential Ψs, relative water content (RWC), turgor potential (Ψp ), and the osmotic adjustment (OA) of leaves and roots. SA 0.5 mM mitigated the effects of salinity by increasing the Ψw of the leaf, the Ψsof theroot, the Ψpof the leaf, RWC and OA of the leaf; while NO3 was only effective in combination with SA, mitigating the effects of salinity by increasing... |
Tipo: Journal article |
Palavras-chave: Nitrate; Osmotic potential; Osmotic adjustment; Salinity mitigation; Salicylic acid; Water potential; Water relative content. |
Ano: 2010 |
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0718-16202010000300006 |
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Brunetto,Gustavo; Oliveira,Bruno Salvador; Ambrosini,Vítor Gabriel; Couto,Rafael da Rosa; Sete,Paula Beatriz; Santos Junior,Elano dos; Loss,Arcângelo; Silva,Lincon Oliveira Stefanello da; Gatiboni,Luciano Colpo. |
ABSTRACT: Weed management in apple orchards (Malus domestica) can affect the leaching of nitrogen (N) in soil. The study aimed to evaluate the potential leaching of N forms in soil of an apple orchard with different weed management treatments. The experiment was conducted in an apple orchard implanted in 2008. In October 2011, 80 plants were selected and the following treatments were implemented: no weed management (NM), desiccation of weeds on the tree row with herbicide use (DR) and mechanical mowing of weeds on the tree row (MR). Yield was evaluated in the 2011/2012, 2012/2013 and 2013/2014 crop seasons. In May 2012 porous cup lysimeters were installed in the NM, DR and MR treatments. In the solution collected at 0.20m, NH4 +-N and NO3 --N were analyzed... |
Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Mineral N; Nitrate; Ammonia; Malus domestica. |
Ano: 2018 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0103-84782018000500251 |
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Campos García, Tonatiu. |
El objetivo de la presente investigación fue estudiar el efecto de las relaciones (en la solución nutritiva) amonio/nitrato (NH4+/NO3-) y calcio/potasio (Ca2+/K+) en plantas de fresa Fragaria x ananassa cv. Festival, cultivadas en fibra de coco en un sistema hidropónico. Los tratamientos de NH4+/NO3- fueron 100/0, 75/25, 25/75 y 0/100 en porcentaje de nitrógeno total y 58/42, 75/25, 50/50, 25/75 de Ca2+/K+. Los resultados obtenidos indicaron que las plantas con mayor crecimiento vegetativo y área foliar fueron las que se cultivaron con el tratamiento 100/0 donde se adicionó el 100% de nitrógeno en forma de amonio. También se observó que la corona es el órgano de la planta que concentra la mayor cantidad de NH4+ y NO3-. La concentración de azúcares y... |
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Palavras-chave: Fresa; Amonio; Nitrato; Relaciones; Producción; Strawberry; Ammonium; Nitrate; Ratio; Yield; Edafología; Maestría. |
Ano: 2014 |
URL: http://hdl.handle.net/10521/2306 |
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Paparazzo,Flavio E.; Alder,Viviana A.; Schloss,Irene R.; Bianchi,Alejandro; Esteves,Jose L.. |
The Drake Passage (DP) links the Southern Pacific and Atlantic Oceans, and acts as a physical narrowing for the largest current of the World Ocean, the Antarctic Circumpolar Current (ACC). This result in a constriction of the main circumpolar fronts related to the ACC: the Subantarctic Front, the Polar Front, the Southern Antarctic Circumpolar Current Front and the Continental Water Boundary Front. Previous studies showed that the DP is a high-nutrient low-chlorophyll (HNLC) region, but studies on the interannual and seasonal macronutrients' fluctuations in relation with chlorophyll and frontal areas in the DP are scarce. This study analyzes the spatial and temporal trends of nitrate, phosphate, and silicate on surface samples from 113 oceanographic... |
Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Nitrate; Phosphate; Silicate; Chlorophyll-a; Temperature; Salinity; Antarctic fronts; Antarctic zones; Seasonal variation; Interannual variation. |
Ano: 2016 |
URL: http://www.scielo.org.ar/scielo.php?script=sci_arttext&pid=S1667-782X2016000100004 |
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Assis,Tatiane M. de; Schilichting,Marcos V.; Lopes,Carla L.; Kunz,Airton; Gomes,Simone D.. |
ABSTRACT The aim of this study was to monitor the stabilization of a sequential batch reactor (SBR) regarding the partial nitritation of poultry slaughterhouse wastewater, aiming at preparing it for a reactor with bacteria that promote anaerobic ammonia oxidation (anammox). A cylindrical reactor with a useful volume of 3.5 L, mechanical agitation (50 rpm), and suspended biomass was used in the experiment. The strategies adopted for nitrite-oxidizing bacteria (NOB) inhibition were cycle time (CT: 24, 16, 6, 5, 4 h and real-time monitoring), free ammonia accumulation, alkalinity restriction and low concentrations of dissolved oxygen (DO). The ammonification process, observed at all experimental phases, negatively influenced the control of partial nitritation... |
Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Anammox; Deammonification; Nitrite; Nitrate; Nitrafying. |
Ano: 2017 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0100-69162017000200323 |
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Kenneth W,Bruland. |
This presentation is a review of the chemistries of redox sensitive elements within suboxic regions of extreme oxygen minimum zones. Suboxic regions are defined as extreme oxygen minimum zones with dissolved oxygen < 10 µmol kg-1 (and likely <5 µmol kg-1), and with clear evidence of nitrate reduction, but not sulfate reduction. These are regions with nitrate deficits > 10 µmol kg-1 or N* values of _10 µmol kg-1. Suboxic regions predictably occur in the tropical and subtropical eastern Pacific and the Arabian Sea. These suboxic zones are important in the global biogeochemistry of nitrogen and act as an important sink for fixed nitrogen. Minor and trace element redox couples such as iodate/iodide and leachable particulate Mn/dissolved Mn undergo... |
Tipo: Journal article |
Palavras-chave: Nitrate; Iodine; Manganese; Iron. |
Ano: 2006 |
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-65382006000300003 |
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Oyarzún,Carlos; Godoy,Roberto; Staelens,Jeroen; Aracena,Claudia; Proschle,Juan. |
Forest structure and tree species can have a significant impact on total atmospheric nitrogen (N) deposition; for example, deciduous forests have higher N requirements than coniferous forests. However, knowledge about the effect of the conversion of native Chilean vegetation cover by exotic plantations on N cycling is scarce. The aim of this study was to determine the effect of the replacement of a Nothofagus obliqua native forest by a Pinus radiata plantation in southern Chile on the chemistry of throughfall, stemflow, soil water infiltration and percolation. Pinus radiata stemflow was more acidic (pH 4.7) than precipitation (pH 5.2) and throughfall (pH 5.6), while in the Nothofagus forest stemflow and throughfall pH were 6.3 and 6.1, respectively. In the... |
Tipo: Journal article |
Palavras-chave: Ammonium; Infiltration; Nitrate; Soil percolation; Throughfall. |
Ano: 2005 |
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-66432005000200004 |
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Staelens,Jeroen; Godoy,Roberto; Oyarzún,Carlos; Thibo,Karen; Verheyen,Kris. |
Nitrogen return by leaf litterfall was compared with atmospheric nitrogen deposition for two deciduous Nothofagus stands in southern Chile, located in areas with contrasting land use. The litterfall return of nitrogen in a Nothofagus alpina (Poepp. et Endl.) Oerst. stand at San Pablo de Tregua, in the Cordillera de los Andes, was similar to the litterfall return in a Nothofagus obliqua (Mirb.) Oerst. stand at Paillaco, in the Central Depression. In contrast, the net throughfall and stemflow deposition differed significantly between the two stands. At San Pablo de Tregua, the annual bulk deposition of NH4+ and NO3- was significantly higher than the throughfall and stemflow deposition reaching the forest floor. This demonstrates an uptake of inorganic... |
Tipo: Journal article |
Palavras-chave: Ammonium; Atmospheric deposition; Canopy interactions; Nitrate; Nutrient cycling; Amonio; Ciclos de nutrientes; Depositación atmosférica; Interacciones del dosel; Nitrato. |
Ano: 2005 |
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-66432005000200002 |
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Alvarez,José M; Pasian,Claudio; Lal,Rattan; López,Rafael; Fernández,Manuel. |
ABSTRACT Containerized ornamental plant production is facing several environmental challenges. One of them is to replace the widely used, but with questionable sustainability, peat based substrates and another is to avoid water contamination by chemicals leaching from the nursery. Therefore, as have been verified that petunia and pelargonium plants can be produced in peat-based growing media partially replaced by vermicompost (V) and biochar (B) without decreasing commercial quality, this study has focused on analyzing the leachate from a standard peat-based substrate as a control, used for producing these two ornamental species, and those from the same substrate to which different proportions in volume of V (10% and 20%) and B (4% and 12%) have been... |
Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Petunia hybrida; Pelargonium peltatum; Peat replacement; Water contamination; Nitrate; Phosphate. |
Ano: 2019 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0102-05362019000100047 |
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ANDRADE, S. R. M.; SANT'ANNA, R.; MOSQUIM, P. R.; CAMBRAIA, J.. |
Visando a elucidar alguns aspectos do metabolismo do nitrogenio por plantas de Panicum maximum, estudaram-se os efeitos da proporcao NH +4/NO-3 na variacao do pH das solucoes nutritivas de tratamento, no acumulo de materia seca e na distribuicaoo de nitrogenio na planta. Para tal, as plantas foram cultivadas em camara de crescimento na solucao nutritiva (pH 5,5) completa, contendo nitrogenio somente na forma nitrica. Aos 25 dias depois da germinacao, as plantas foram submetidas a 100 ppm de nitrogenio fornecido nas formas nitrica e amoniacal ou amonical, nas seguintes proporcoes 0/100,25/75,50/50,75/25 e 100/0, durante quatro dias. O pH das solucoes nutritivas foi medido e corrigido diariamente. Os resultados demostraram que o pH aumentou na presenca... |
Tipo: Folhetos |
Palavras-chave: Amonio; Absorcao de nitrogenio; Nitrogen uptake; Ammonium; Nitrate; Fisiologia vegetal: Nutricao mineral; Capim Colonião; Cerrado; Fisiologia Vegetal; Nitrogênio; Nitrato; Panicum Maximum; Plant physiology. |
Ano: 2001 |
URL: http://www.infoteca.cnptia.embrapa.br/infoteca/handle/doc/567073 |
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Registros recuperados: 59 | |
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