Nitrate Ions

We present here the preparation of anionic dimeric and hexameric C-alkylpyrogallol[4]arene nanocapsules by attaching multiple nitrate ions to the nanocapsule surface via metal coordination. These anionic nanocapsules can be utilized for encapsulation of cationic guest molecules and have potential applications in catalysis, sensing, and biomedicine. This study demonstrates that the surface functionalization may act as an effective method to tailor and introduce new properties to metal− organic nanocapsules.

The aim of this study is to investigate the performance of zinc oxide nano-cages (Zn 12 O 12-NC) to detect and reduce nitrate (NO 3-) ions from aqueous media and convert them to oxygen and nitrogen gases by the density functional theory (DFT) method on a B3LYP level with basis set of 6-31+G*. Due to the structure of the nano-cage (Zn 12 O 12-NC), there are some location positions with different potential on it. The results showed that the first N atom of nitrate ion strongly prefers to be adsorbed on O atoms and O of nitrate ion is adsorbed on Zn atoms of the 4-membered ring (4-MR). The electronic, structure and thermodynamic properties of these conversions are calculated and investigated. The energy gap (E g) of the Zn 12 O 12-NC is dramatically reduced from 3.88 to 1.22 eV upon the adsorption of NO 3ion, suggesting that it is transformed to n-type semiconductor ascribed to the large charge transfer from the ion to the nano-cage and ions convert into oxygen and nitrogen on it. The data show that Zn 12 O 12 nano-cage can be used to identify and reduce nitrate ions from the environment and may be helpful in several fields of study such as sensors, catalysts, and field emission investigations.

The yield of molecular hydrogen, as a function of nitric acid concentration, from the α-radiolysis of aerated nitric acid and its mixtures with sulfuric acid containing plutonium or americium has been investigated. Comparison of experimental measurements with predictions of a Monte Carlo radiation track chemistry model shows that, in addition to scavenging of the hydrated electron, its precursor, and the hydrogen atom, the quenching of excited state water is important in controlling the yield of molecular hydrogen. In addition, increases in solution acidity cause a significant change in the track reactions, which can be explained as resulting from scavenging of e by H to form H. Although plutonium has been shown to be an effective scavenger of precursors of molecular hydrogen below 0.1 mol dm nitrate, previously reported effects of plutonium on G(H) between 1 and 10 mol dm nitric acid were not reproduced. Modeling results suggest that plutonium is unlikely to effectively compete wit...

The aim of this study is to investigate the performance of zinc oxide nano-cages (Zn12O12-NC) to detect and reduce nitrate (NO3-) ions from aqueous media and convert them to oxygen and nitrogen gases by the density functional theory (DFT) method on a B3LYP level with basis set of 6-31+G*. Due to the structure of the nano-cage (Zn12O12-NC), there are some location positions with different potential on it. The results showed that the first N atom of nitrate ion strongly prefers to be adsorbed on O atoms and O of nitrate ion is adsorbed on Zn atoms of the 4-membered ring (4-MR). The electronic, structure and thermodynamic properties of these conversions are calculated and investigated. The energy gap (Eg) of the Zn12O12-NC is dramatically reduced from 3.88 to 1.22 eV upon the adsorption of NO3- ion, suggesting that it is transformed to n-type semiconductor ascribed to the large charge transfer from the ion to the nano-cage and ions convert into oxygen and nitrogen on it. The data show ...

The aim of this study is to investigate the performance of zinc oxide nano-cages (Zn12O12-NC) to detect and reduce nitrate (NO3-) ions from aqueous media and convert them to oxygen and nitrogen gases by the density functional theory (DFT) method on a B3LYP level with basis set of 6-31+G*. Due to the structure of the nano-cage (Zn12O12-NC), there are some location positions with different potential on it. The results showed that the first N atom of nitrate ion strongly prefers to be adsorbed on O atoms and O of nitrate ion is adsorbed on Zn atoms of the 4-membered ring (4-MR). The electronic, structure and thermodynamic properties of these conversions are calculated and investigated. The energy gap (Eg) of the Zn12O12-NC is dramatically reduced from 3.88 to 1.22 eV upon the adsorption of NO3- ion, suggesting that it is transformed to n-type semiconductor ascribed to the large charge transfer from the ion to the nano-cage and ions convert into oxygen and nitrogen on it. The data show that Zn12O12 nano-cage can be used to identify and reduce of nitrate ions from the environment and may be helpful in several fields of study such as sensors, catalysts, and field emission investigations.

The aim of this study is to investigate the performance of zinc oxide nano-cages (Zn12O12-NC) to detect and reduce nitrate (NO3-) ions from aqueous media and convert them to oxygen and nitrogen gases by the density functional theory (DFT) method on a B3LYP level with basis set of 6-31+G*. Due to the structure of the nano-cage (Zn12O12-NC), there are some location positions with different potential on it. The results showed that the first N atom of nitrate ion strongly prefers to be adsorbed on O atoms and O of nitrate ion is adsorbed on Zn atoms of the 4-membered ring (4-MR). The electronic, structure and thermodynamic properties of these conversions are calculated and investigated. The energy gap (Eg) of the Zn12O12-NC is dramatically reduced from 3.88 to 1.22 eV upon the adsorption of NO3- ion, suggesting that it is transformed to n-type semiconductor ascribed to the large charge transfer from the ion to the nano-cage and ions convert into oxygen and nitrogen on it. The data show that Zn12O12 nano-cage can be used to identify and reduce of nitrate ions from the environment and may be helpful in several fields of study such as sensors, catalysts, and field emission investigations.

Objectives: It is to determine the suitability of cultivating green microalgae: Tetraspora sp. and Spirogyra sp. that are cultured in Sungai Sura of Dungun, Terengganu, Malaysia as a water source. Methods: The microalgae strains have been cultured in an indoor laboratory of Environmental Research Center, UiTM Dungun for 20 days in the low salinity water medium ranges of 120 to 150 µS/cm. The cultivation process significantly grown in 20 days. Findings: It is also shown the positive correlation between growth rate and cultivation days of Tetraspora sp. and Spirogyra sp. However, Tetraspora sp. gives higher densities than Spirogyra sp. when an assessment carried out in the similar days within 20 day cultivation periods. The maximum biomass concentration of Tetraspora sp. is 7.37 mg/ml and Spirogyra sp. is 3.16 mg/ ml. Applications/Improvements: Tetraspora sp. generate more than double biomass densities than Spirogyra sp. on the similar days within 20 day cultivation periods. Both species were successfully grown indoors in the Sungai Sura water source, where salinity is lower as a cultivation medium.

Mesoporous silica particles with various morphologies and structures have been synthesized by controlling the solubility, micellization, and assembly of a charged surfactant (cethyltrimethylammonium bromide, CTAB) and a pluronic (PEO 20 PPO 70 PEO 20 , P123) couple using an organic (benzene) or an inorganic (SO 4 2-, NO 3-, or Cl-) additive. The effect of CTAB, with or without one of the Hofmeister ions or benzene in various concentrations, on the morphology, pore-size, pore-structure and the nature of the silica particles has been investigated. Increasing the lyotropic anion (SO 4 2-) or benzene concentration of the synthesis media creates wormlike particles with enlarged pores and reduced wall thickness. However, the hydrotropic anion (NO 3-) influenced the solubility of the charged surfactant and increased the CTAB concentration in the CTAB-P123 micelles, and as a result, in the mesoporous silica particles. The surface area, unit cell, and pore size of the silica particles are diminished by increasing the nitrate ion centration. The effects of the Clion are between the SO 4 2and NO 3 ions. It influenced the P123 at low and CTAB at high concentrations. At low CTAB/ P123 mol ratios, the Clion affects mainly the P123, but at high CTAB/P123 it affects both the CTAB and P123. By carefully adjusting these ingredients (CTAB, SO 4 2-, Cl-, NO 3 and benzene), not only the morphology of the particles, but also the pore-size and pore-structure of the mesoporous silica particles could be adjusted. The investigations were carried out by preparing a series of powder samples and, by varying the CTAB/P123 mol ratio (between 3.0 and 6.0) and the concentration of the organic (0.17 to 0.90 M) or inorganic (at 0.25, 0.50, or 1.00 M) additive in the synthesis media. The powder samples were analyzed using microscopy (SEM, TEM, and POM), diffraction (PXRD), and spectroscopy (FTIR, Raman, UV-vis, and EDS) techniques toward above goals.

The ‘Spartacus’ F1 sweet pepper was grown in a plastic tunnel on rockwool during 2006-2008. A fertigation technique was used for water and fertiliser application. The tunnel was divided into two parts covered with different plastic films. The first part of the tunnel was covered with a film that transmitted less light than the film covering the second part. In both parts of the tunnel, the plants were divided into two groups. One group of plants was fertilised with just nitrate nitrogen (100% N-NO3) and the other one with three forms of nitrogen (N-NO3:N-NH4:N-NH2 in a ratio of 50:13:37). Fruits were harvested mature green and red. Concentrations of nitrate and ammonium ions as well as total nitrogen and free amino acids were analysed in the plant material. Nitrate and nitrite reductase activities were also investigated, and dry matter content and soluble sugars were also determined. Higher light intensity increased nitrate concentration in red pepper fruits but decreased ammonium i...

Aquaculture activity on coastal area produces organic and inorganic waste that cause a high concentration of dissolved nutrient in waters. Therefore, the organic and inorganic waste should be reduced to prevent a negative impact to coastal water. One way to reduce the aquaculture waste loading to coastal water is to use it as a fertilizer on microalgae cultivation. The objective of this study was to investigate the change of dissolved nitrogen concentration in aquaculture waste during 14 days treatment in aerated and unaerated conditions. Two liters of wastewater was collected every 2 days from the reactor for culture media of microalgae Nannochloropsis oculata in 2 liters Erlenmeyer flask. The concentration of ammonia, nitrite, nitrate and phosphate were determined spectrophotometrically as well as chlorophyll-a content when waste were treated in aerated and unaerated reactor. Water temperature, dissolved oxygen, hydrogen ion and salinity were monitored throughout the treatment. Concentration of ammonia, nitrate and nitrite in aeration treatment were changed faster in aerated condition compared to unaerated condition. The phosphate concentration in both aerated and unaerated had a same pattern and these could reach the highest concentration to 0,9 mg L-1. Six days cultivation of N. oculata showed that N. oculata was able to assimilate nutrient from wastewater to construct its cell structure with the highest density of 19,75 x 10 6 cell mL-1 and its process caused extremely low nutrient concentration. This result showed that nutrient from aquaculture waste can be almost totally assimilated by N. oculata and create an extremely low concentration of nutrient from wastewater.

Objectives: It is to determine the suitability of cultivating green microalgae: Tetraspora sp. and Spirogyra sp. that are cultured in Sungai Sura of Dungun, Terengganu, Malaysia as a water source. Methods: The microalgae strains have been cultured in an indoor laboratory of Environmental Research Center, UiTM Dungun for 20 days in the low salinity water medium ranges of 120 to 150 µS/cm. The cultivation process significantly grown in 20 days. Findings: It is also shown the positive correlation between growth rate and cultivation days of Tetraspora sp. and Spirogyra sp. However, Tetraspora sp. gives higher densities than Spirogyra sp. when an assessment carried out in the similar days within 20 day cultivation periods. The maximum biomass concentration of Tetraspora sp. is 7.37 mg/ml and Spirogyra sp. is 3.16 mg/ ml. Applications/Improvements: Tetraspora sp. generate more than double biomass densities than Spirogyra sp. on the similar days within 20 day cultivation periods. Both species were successfully grown indoors in the Sungai Sura water source, where salinity is lower as a cultivation medium.

Streszczenie. W pracy badano wpływ wielkości i części korzenia buraka ćwikłowego na zawartość barwników betalainowych, betainy, azotanów(V) oraz na aktywność przeciwutleniającą soku z buraka ćwikłowego odmiany Bonel. Surowiec podzielono pod względem masy na cztery grupy wielkościowe: A -151-200, B -201-300, C -301-400, D ->400 g. W obrębie każdej grupy korzenie krojono poprzecznie do osi na cztery części, umownie oznaczone: G, GCP, ŚCP i DCP. Z tak podzielonych buraków przygotowano sok. Stwierdzono, że wartości wszystkich badanych wyróżników zależały od wielkości i części korzenia. Największą zawartość barwników betalainowych miały soki z korzeni buraków z grupy wielkościowej A. Korzenie z grupy wielkościowej C i D odznaczały się największą zawartością azotanów(V). W porównaniu ze środkowymi częściami korzenia buraka, górna i dolna części miały większą zawartość barwników i większą aktywność przeciwutleniającą, ale mniejszą zawartość azotanów(V). Aktywność przeciwutleniająca soku była istotnie skorelowana z zawartością barwników. Słowa kluczowe: burak ćwikłowy, barwniki betalainowe, betaina, azotany(V), aktywność przeciwutleniająca WSTĘP Najważniejszym narzędziem w kształtowaniu właściwości i jakości produktu żywnościowego jest odpowiedni dobór surowca. Wykorzystanie surowca o dużej zawartości związków biologicznie aktywnych, ale o małej zawartości substancji antyodżywczych

The aim of the study was to examine the effect of spraying two herbicidal ionic liquid forms of MCPA (HILs-[Etq O-12][MCPA], [DDA][MCPA]) on chlorophyll a + b content in leaves of spring barley (Hordeum vulgare L.). Spectrophotometric method was used to measure chlorophyll a + b content 24 and 72 h after fields were sprayed. The data was compared to controls that consisted of the treatments using a commercial formulation of MCPA as a salt or ester. The field studies revealed that after 24 h of MCPA as a salt spraying chlorophyll a + b content in spring barley was lower by 12% and after 72 h by 18%. The application of MCPA as an ester lowered the chlorophyll a + b amount by just 9%, as a HILs resulted in decrease by about 3% compared to control plots. The results do not confirm a significant impact on the content of photosynthetic pigments in spring barley, but they show that the application of HILs as an alternative herbicide can reduce the undesirable effects of MCPA.

S t r e s z c z e n i e. Marchew 'Kazan F 1 ' uprawiano w latach 2004-2005 w pojemnikach aŜuro-wych o wymiarach 60×40×20 cm, umieszczonych na terenie otwartym pod cieniówką, wypełnio-nych gliną średnią pylastą (30% piasku, 28% pyłu, 37% iłu) o średniej zawartości substancji orga-nicznej 3,25%. Zawartość przyswajalnych form składników mineralnych uzupełniono do poziomu: 100 mg N, 80 mg P, 120 mg K, 80 mg Mg, 2000 mg Ca·dm-3 gleby. Badaniami objęto podbloki z roślinami niedokarmianymi i dokarmianymi dolistnie przy przemiennym zastosowaniu 2% mocznika, 1% Supervitu R, ponownie 2% mocznika. W ramach podbloków wyróŜniono obiekty z doglebowym nawoŜeniem azotem: kontrola (nienawoŜona N), Ca(NO 3) 2 , NH 4 NO 3 , (NH 4) 2 SO 4 i CO(NH 2) 2. NawoŜe-nie azotem spowodowało podwyŜszenie masy pojedynczych korzeni oraz zawartości NO 3-i N-ogółem oraz aktywności reduktazy azotanowej (NR) i reduktazy azotynowej (NiR) w korzeniach spichrzowych. Nie wpłynęło natomiast na zawartość suchej masy...

S t r e s z c z e n i e. Celem pracy było zbadanie wpływu dokarmiania dolistnego mocznikiem i nawozem wieloskładnikowym Supervit-R oraz róŜnych rodzajów nawozów azotowych (Ca(NO 3) 2 , NH 4 NO 3 , (NH 4) 2 SO 4 i CO(NH 2) 2) wprowadzonych doglebowo na metabolizm azotanów w liściach marchwi oraz porównanie badanych procesów z równolegle przebiegającymi w korzeniach. Obiek-tem badań była marchew 'Kazan F 1 ', którą uprawiano w latach 2004-2005 w pojemnikach aŜuro-wych na terenie otwartym. Połączenie nawoŜenia doglebowego zredukowanymi formami azotu z dokarmianiem pozakorzeniowym stymulowało aktywność NR w liściach w porównaniu z rośli-nami niedokarmianymi. Wykazano wzrost aktywności NiR i zawartości NO 3-oraz spadek poziomu NH 4 + w liściach marchwi od sierpnia (tuŜ przed ostatnim zabiegiem dokarmiania dolistnego) do września (termin zbioru) niezaleŜnie od rodzaju nawozu azotowego. Dokarmianie dolistne wpłynęło na istotne zwiększenie zawartości NO 3-w liściach marchwi, natomia...

The results of three year investigations with 'Galaxy' F 1 cabbage grown under field conditions are presented. The effect of the rate of ammonium sulphate and RSM (solution of ammonium nitrate + urea), the method of application (placement and broadcast technique) and foliar fertilization (urea and Supervit K) on the yield and nitrate accumulation was studied. The form of N fertilizer significantly increased the cabbage yield only in 2007. In this year the better nitrogen source was ammonium sulphate in comparison with RSM. In the other years no differences between the kind of N fertilizer were observed. The method of application did not affect cabbage yield any year. However, slightly better cropping was noted for following treatments 75% N broadcasted at planting + 25% N during growth season, 75% N broadcasted at planting + foliar fertilization, and after placement fertilization with reduced rate (75% N) as compared to control (100% N broadcasted at planting), in every year of the experiment. In 2006 and 2007 fertilization at the rate of 75% N and supplemented with addition 25% N during the growth or foliar sprays significantly increased nitrate content in cabbage as compared to control treatment.

The treatment of nitrate and phosphate ions in fresh water such as streams, rivers, lakes,
reservoirs, and wetlands through biological treatment has been getting more crucial and popular
in recent years. This paper reports the reduction of nitrate and phosphate ions in modified low
salinity fresh water via the cultivation of a microalgae strain, e.g., Tetraspora sp. and Spirogyra sp.
The low salinity fresh water (9054 to 9992 ppm) was modified with the addition of organic fertiliser
(VermiCompost Tea) and used as the cultivation medium to grow microalgae. The microalgae strains
were grown under controlled conditions in an indoor laboratory for 14 days. The initial concentrations
of nitrate and phosphate ions in the modified fresh water sample were 1.17 mg/L and 0.10 mg/L,
respectively. The reduction of nitrate and phosphate ions associated with the effect of cultivation
of Tetraspora sp. and Spirogyra sp. in ambient air (0.03% of CO2) and 15% of CO2 was investigated.
In ambient air, the cultivation of Tetraspora sp. and Spirogyra sp. greatly reduced the nitrate ions
concentration from 5.96  0.28 to 0.37  0.05 mg/L and from 2.35  0.19 to 0.59  0.08 mg/L,
respectively. A 100% reduction of phosphate ions was observed in the cultivation of Tetraspora sp. and
Spirogyra sp. from 0.52  0.10 mg/L in 13 days of and from 0.63  0.15 mg/L in 6 days, respectively.
Meanwhile, with the aeration of 15% of CO2, after the 14 days cultivation of Tetraspora sp. and
Spirogyra sp. reduced the nitrate ions concentration from 5.27  0.06 to 1.80  0.20 mg/L and from
4.73  0.12 to 2.80  0.10 mg/L, respectively. The excessive CO2 in water consequently lowered the
pH of water medium from 7.18 to 6.60 due to the formation of carbonic acid (H2CO3). It was feasible
to couple the removal of nitrogen and phosphorus in Sungai Sura (442”28.2 N 10326”12.1 E)
while cultivating microalgae through biological treatment to produce biomass for biofuel production.

Abstrakt: Celem badań było określenie wpływu oddziaływania jodu, aplikowanego w formie Ii IO 3 -, na efektywność pobierania tego pierwiastka (przez owoce i liście), plonowanie oraz gospodarkę azotem roślin pomidora (Lycopersicon esculentum Mill.) 'Rambozo F 1 '. Pomidora uprawiano w 2010 roku, w szklarni, w systemie hydroponicznym cienkowarstwowych kultur przepływowych (CKP). Obiektami badań były: 1. Kontrola; 2. 1 mg I•dm -3 pożywki w formie KI; 3. 1 mg I•dm -3 pożywki w formie KIO 3 . W liściach i ogonkach liściowych pomidora nawożonych KI stwierdzono odpowiednio 8,1 i 4,7 razy więcej jodu niż traktowanych KIO 3 . Najniższą zawartość azotu ogółem w owocach stwierdzono w obiekcie kontrolnym, zaś azotanów(V) w obiekcie z pożywką wzbogaconą w jod w formie KIO 3 . Pomimo braku istotnych różnic statystycznych należy wspomnieć, że zawartość jodu w owocach traktowanych tym pierwiastkiem w formie KI i KIO 3 była wyższa niż w kontroli, odpowiednio o 116,2% i 10,5%.

Fertilization with (NH 4 ) 2 SO 4 and foliar nutrition lowered soluble sugar content in carrot. Storage roots of plants fertilized with Ca(NO 3 ) 2 contained the least amount of phenolic compounds. Foliar nutrition did not have any effect on phenolic compound concentrations in carrot. Foliar nutrition and treatment with NH 4 NO 3 , (NH 4 ) 2 SO 4 or CO(NH 2 ) 2 did not affect carotenoid concentrations.

Various forms of nitrogen fertilizer were applied in the cultivation of red cabbage (in the years [2003][2004][2005], 'Langendijker' c.v.: control (unfertilized with nitrogen), Ca(NO 3 ) 2 , (NH 4 ) 2 SO 4 , NH 4 NO 3 , CO(NH 2 ) 2 applied as solid fertilizers. This experiment aimed at determining the influence of various nitrogen forms on the content of Al, B, Cd, Co, Cr, Cu, Fe, Li, Mn, Mo, Ni, Pb, Sr, Ti, Zn, V in cabbage heads and the changes in the content of the available form of these elements for plants in soil after cabbage cultivation. The heads of plants fertilized with calcium nitrate and urea were characterized by the highest content of Al, Mn, Sr, Zn, Cd and Mo. Urea caused a significant increase in the content of Cu, Li and V, while ammonium nitrate resulted in an elevated level of Fe and Co accumulation in cabbage heads. Fertilization with (NH 4 ) 2 SO 4 led to a substantial decrease in the content of Al, Mo and V, and fertilization with NH 4 NO 3 caused a decline in Sr concentrations in cabbage in comparison with other objects of the experiment. Each nitrogen fertilizer resulted in the decreased concentrations of Ti in cabbage heads. Applied nitrogen fertilizers significantly influenced the contents of readily soluble forms of B, Fe and Pb in soil after cabbage cultivation.

The Kazan F 1 carrot was cultivated in years [2004][2005] in open-work containers sized 60×40×20 cm filled in with silt loam and located on the open field under shade providing fabric. The following combinations of experiments were arranged: (1) control -without foliar nutrition, and foliar nutrition with:

S t r e s z c z e n i e . Celem pracy było zbadanie wpływu dokarmiania dolistnego mocznikiem i nawozem wieloskładnikowym Supervit-R oraz róŜnych rodzajów nawozów azotowych (Ca(NO 3 ) 2 , NH 4 NO 3 , (NH 4 ) 2 SO 4 i CO(NH 2 ) 2 ) wprowadzonych doglebowo na metabolizm azotanów w liściach marchwi oraz porównanie badanych procesów z równolegle przebiegającymi w korzeniach. Obiektem badań była marchew 'Kazan F 1 ', którą uprawiano w latach 2004-2005 w pojemnikach aŜurowych na terenie otwartym. Połączenie nawoŜenia doglebowego zredukowanymi formami azotu z dokarmianiem pozakorzeniowym stymulowało aktywność NR w liściach w porównaniu z roślinami niedokarmianymi. Wykazano wzrost aktywności NiR i zawartości NO 3 oraz spadek poziomu NH 4 + w liściach marchwi od sierpnia (tuŜ przed ostatnim zabiegiem dokarmiania dolistnego) do września (termin zbioru) niezaleŜnie od rodzaju nawozu azotowego. Dokarmianie dolistne wpłynęło na istotne zwiększenie zawartości NO 3 w liściach marchwi, natomiast nie miało wpływu na zawartość barwników asymilacyjnych. śywienie azotowe roślin modyfikowało udział liści i korzeni spichrzowych marchwi w redukcji azotanów i azotynów.

S t r e s z c z e n i e . Marchew 'Kazan F 1 ' uprawiano w latach 2004-2005 w pojemnikach aŜurowych o wymiarach 60×40×20 cm, umieszczonych na terenie otwartym pod cieniówką, wypełnionych gliną średnią pylastą (30% piasku, 28% pyłu, 37% iłu) o średniej zawartości substancji organicznej 3,25%. Zawartość przyswajalnych form składników mineralnych uzupełniono do poziomu: 100 mg N, 80 mg P, 120 mg K, 80 mg Mg, 2000 mg Ca·dm -3 gleby. Badaniami objęto podbloki z roślinami niedokarmianymi i dokarmianymi dolistnie przy przemiennym zastosowaniu 2% mocznika, 1% Supervitu R, ponownie 2% mocznika. W ramach podbloków wyróŜniono obiekty z doglebowym nawoŜeniem azotem: kontrola (nienawoŜona N), Ca(NO 3 ) 2 , NH 4 NO 3 , (NH 4 ) 2 SO 4 i CO(NH 2 ) 2 . NawoŜenie azotem spowodowało podwyŜszenie masy pojedynczych korzeni oraz zawartości NO 3 i N-ogółem oraz aktywności reduktazy azotanowej (NR) i reduktazy azotynowej (NiR) w korzeniach spichrzowych. Nie wpłynęło natomiast na zawartość suchej masy w korzeniach marchwi. Dokarmianie dolistne spowodowało obniŜenie masy pojedynczych korzeni spichrzowych. Korzenie spichrzowe roślin dokarmianych dolistnie zawierały więcej N-ogółem oraz charakteryzowały się wyŜszą aktywnością NR w porównaniu z roślinami niedokarmianymi. Dokarmianie dolistnie nie wpłynęło na zawartość: suchej masy, NO 3 -, NH 4 + jak równieŜ aktywność NiR w korzeniach spichrzowych. Współdziałanie dokarmiania dolistnego × nawoŜenie miało istotny wpływ na masę korzeni oraz zawartość NO 3 jak i aktywność NiR; nie wpłynęło natomiast na zawartość NH 4 + , N-ogółem, suchej masy i aktywność NR w korzeniach spichrzowych marchwi.