INFLUENCE DU CLIMAT SUR L’ACTIVITÉ NITRATE RÉDUCTASE AU COURS DU DÉVELOPPEMENT DE SIX VARIÉTÉS D’AVOINE

1989 ◽  
Vol 69 (3) ◽  
pp. 919-923 ◽  
Author(s):  
A. SAUVESTY ◽  
G. GENDRON
Keyword(s):  
Environmental Factors ◽  
Nitrate Reductase ◽  
Plant Development ◽  
Significant Influence ◽  
Environmental Conditions ◽  
Nitrate Reductase Activity ◽  
Nitrate Nitrogen ◽  
Reductase Activity ◽  
Stage Of Development ◽  
Nr Activity

The influence of field climate on nitrate reductase activity (NR) and development was studied in six oat varieties. Of the monitored environmental factors, only temperature had a significant influence; a temperature increase accelerated plant development and increased NR. It was found that a measure of NR activity as early as the coleoptile stage of development indicated optimal environmental conditions for reduction of nitrate nitrogen in a given genotype.Key words: Nitrate reductase activity, development, climate, oat

scholarly journals Effects of growth retarding compounds on chlorophyll accumulation and nitrate reductase activity in nitrate induced cucumber cotyledons

2015 ◽  
Vol 42 (3) ◽  
pp. 431-439 ◽  
Author(s):  
J. S. Knypl
Keyword(s):  
Nitrate Reductase ◽  
Nitrate Reductase Activity ◽  
Reductase Activity ◽  
Chlorophyll Synthesis ◽  
Growth Retardants ◽  
Chlorophyll Accumulation ◽  
High Concentrations ◽  
Amo 1618 ◽  
Nr Activity

Cotyledons were excised from 5-day old etiolated cucumber seedlings and .grown for 24 or 48 h in solutions of plant growth retardants: AMO-1618,B-Nine, CCC and phosfon D, supplemented with KNO<sub>3</sub> (10<sup>-2</sup>M) in light. Nitrate reductase (NR) activity was determined <i>in vivo</i>. CCC and Phosfon D at high concentrations had no effect on nitrate reductase activity in 24 h tests. CCC at 5xl0<sup>-2</sup> M enhanced NR activity in longer 48 h tests; Phosfon D was inhibitory in that case. AMO-1618 markedly decreased NR activity. B-Nine strikingly enhanced NR activity in KNO<sub>3</sub> induced cytoledons; the effect was positively correlated with the concentration of B-Nine. Ali the compounds inhibited chlorophyll synthesis.

scholarly journals THE EFFECT OF PURIFIED AMOUNT OF TRITERPENE GLYCOSIDES AND THEIR ENRICHED EXTRACT FROM LEAVES OF SILPHIUM PERFOLIATUM L. ON THE GROWTH AND ACTIVITY OF NITRATE REDUCTASE OF WIN-TER WHEAT PLANTS

2019 ◽  
pp. 441-448 ◽  
Author(s):  
Eleonora Sergeyevna Davidyants
Keyword(s):  
Nitrate Reductase ◽  
Winter Wheat ◽  
Seed Treatment ◽  
Nitrate Reductase Activity ◽  
Growth Parameters ◽  
Reductase Activity ◽  
Dry Weight ◽  
Potassium Nitrate ◽  
Triterpene Glycosides ◽  
Nr Activity

The effect of seed treatment with solutions of a purified amount of triterpene glycosides (PATG) containing, as major components, oleanolic acid glycosides – sylphiosides B, C, E, G, and extract (E) enriched with sylphiosides, from Silphium perfoliatum L. (Asteraceae) leaves on growth parameters and nitrate reductase activity (NR, EC 1.6.6.1) of 7-day winter wheat plants (Tritium aestivum L.) was studied. It was shown that, seed treatment with PATG solutions in concentrations of 0.0005 and 0.001% and E in concentrations of 0.2 and 0.4% caused an increase in the length of roots, shoots, wet and dry weight of seedlings compared to the control. The stimulating effect of these concentrations of PATG and E on the total nitrate reductase activity of the roots and leaves of seedlings has been established, and an increase in the stimulating effect of preparations on the activity NR оf against the background of substrate activation of the enzyme potassium nitrate (KNO3) was observed. The greatest increase in the total NR activity of roots and leaves of winter wheat plants was observed when PATG acted at a concentration of 0.001% and E – at a concentration of 0.4%, which amounted respectively 122 and 116%, when adding 1 ml of 50 mM KNO3 solution into the growing medium of plants – 141 and 137% relative to the control. The stimulating effect of exogenous triterpene glycosides on NR activity has been established for the first time. The obtained data allow to theoretically substantiate the possibility of practical use of triterpene glycosides and preparations based on them for the regulation of growth and nitrogen metabolism of plants.

scholarly journals Nitrate reductase activity in leaves and stems of tanner grass (Brachiaria radicans Napper)

2004 ◽  
Vol 61 (6) ◽  
pp. 640-648 ◽  
Author(s):  
Jairo Osvaldo Cazetta ◽  
Luciana Cristine Vasques Villela
Keyword(s):  
Nitrate Reductase ◽  
Plant Development ◽  
Nitrate Reductase Activity ◽  
Reductase Activity ◽  
N Fertilization ◽  
Fresh Weight ◽  
N Supply ◽  
N Management ◽  
Triton X

Tanner grass (Brachiaria radicans Napper) is a forage plant that is adapted to well-drained soils or wetlands, and responds well to nitrogen (N) fertilization. The assimilation of N involves the nitrate reductase (NR) enzyme, and its activity seems to be dependent on N supply. Molybdenum (Mo) is also important because it is a cofactor of NR. In this study, the variables of an in vivo assay were optimized for measuring nitrate reductase activity (NRA) in the leaves and stem tissues. This method was used to evaluate NO3- metabolism in plants fertilized with NaNO3, NH4Cl or urea, in association with or without application of H2MoO4, aiming to provide guidelines for N management of this species. The best conditions to determine NRA involved the incubation of 300 mg of tissues in a medium composed of 200 mmol dm3 phosphate buffer (pH 7.4), 60 mmol dm3 KNO3, 10 cm³ dm3 n-butanol, 0.1 cm³ dm3 detergent (triton-X-100®), under vacuum and in the dark for a period of 60 to 100 minutes. Leaves showed NRA levels two to three times higher than stems. Although there were some interactions between treatments, stem fresh weight and NRA were not affected by N sources. Plants fertilized with NaNO3 showed the best growth and NRA values when compared with NH4Cl and urea, which had, respectively, the lowest and intermediate scores. The application of Mo in the absence of N improved NRA and did not affect leaf and stalk growth. In the presence of N, the Mo levels applied limited leaf NRA and plant development.

scholarly journals Nitrate reductase activity and yield of dry mass and protein content in cucumber seedlings supplied with nitrates and ammonium

2015 ◽  
Vol 48 (3) ◽  
pp. 465-471 ◽  
Author(s):  
J. Buczek ◽  
M. Burzyński
Keyword(s):  
Nitrate Reductase ◽  
Protein Content ◽  
Nutrient Solution ◽  
Nitrate Reductase Activity ◽  
Reductase Activity ◽  
Sole Source ◽  
Dry Mass ◽  
Inhibitory Effect ◽  
Cucumber Seedlings ◽  
Nr Activity

The presence of NH<sub>4</sub><sup>+</sup> ions in a nutrient solution containing NH<sub>4</sub>NO<sub>3</sub> with the K+ ions removed, caused an inhibition of nitrate reductase (NR) activity in cucumber leaves. The lack of K<sup>+</sup> in a NaNO<sub>3</sub> medium also decreased the NR activity. Addition of K<sup>+</sup> to these media suppressed the inhibitory effect of NH<sub>4</sub><sup>+</sup> and enhanced the NR activity in the leaves of plants growing in NaNO<sub>3</sub> nutrient solution. The results suggest that K<sup>+</sup> is essential for NO<sub>3</sub><sup>-</sup> reduction, Na<sup>+</sup> is less effective in this process, whereas NH<sub>4</sub><sup>+</sup> ions markedly inhibit NO<sub>3</sub><sup>-</sup> reduction. The protein content and increment of dry mass of cucumber plants grown 10 days with NH<sub>4</sub>-N as the sole source of nitrogen was significantly lower as compared with NO<sub>3</sub>-N supplied plants feed with plants feed with both forms of mineral nitrogen (NH<sub>4</sub>NO<sub>3</sub>). The results show that cucumber prefers the nitrates, although it can utilize the ammonium form of nitrogen.

Nitrate nitrogen and nitrate reductase activity in Verna lemon tree leaves

1979 ◽  
Vol 1 (4) ◽  
pp. 347-354 ◽  
Author(s):  
C. F. Alcaraz ◽  
E. Banet ◽  
E. Hellín ◽  
S. Llorente
Keyword(s):  
Nitrate Reductase ◽  
Nitrate Reductase Activity ◽  
Nitrate Nitrogen ◽  
Reductase Activity ◽  
Tree Leaves ◽  
Lemon Tree
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