Showing 10 results for Nitrate
N. Najafi, M. Parsazadeh,
Volume 1, Issue 1 (5-2010)
Abstract
In order to study the effect of nitrogen form and pH of nutrient solution on the shoot concentration of P, nitrate, organic N + inorganic ammonium, and total N of spinach, a factorial experiment was conducted with two factors including pH of nutrient solution in three levels (4.5, 6.5 and 8.0) and nitrate to ammonium ratio of nutrient solution in five levels (100:0, 75:25, 50:50, 25:75 and 0:100). This factorial experiment was carried out in a completely randomized design with four replications. Three seedlings of spinach plant (Spinacia oleracea L. Sirius cultivar) were cultivated per pot and were nourished with 15 different nutrient solutions. The results showed that while the effect of nutrient solution pH on the shoot concentration of P, nitrate, and organic N + inorganic ammonium was significant, it was not significant on the shoot concentration of total N. By increasing the nutrient solution pH from 4.5 to 8.0, the shoot concentration of P and nitrate was significantly decreased, but the shoot concentration of organic N + inorganic ammonium, and total N did not change significantly. The main effect of nitrate to ammonium ratio of nutrient solution on the shoot concentration of P, nitrate, organic N + inorganic ammonium, and total N of spinach plant was significant. By increasing the ammonium concentration of nutrient solution, the shoot concentration of nitrate was significantly decreased, while the shoot concentration of P, organic N + inorganic ammonium, and total N of spinach plant was significantly increased. The effect of N form of nutrient solution on the shoot concentration and content of P, nitrate, and total N of spinach plant was dependent on the nutrient solution pH and vice versa. The greatest P concentration in spinach shoots was obtained in nitrate to ammonium ratio of 0:100 and pH of 8.0. The greatest spinach shoots nitrate concentration was found in nitrate to ammonium ratio of 100:0 and pH of 8.0, while the greatest concentrations of organic N + inorganic ammonium and total N in spinach were observed in nitrate to ammonium ratio of 25:75 and pH of 6.5.
S. Beigi, A. Golchin, S. Shafiei,
Volume 2, Issue 2 (7-2011)
Abstract
Abstract
In order to study the effects of different levels of nitrogen (N) and molybdenum (Mo) in nutrient solution on quantitative and qualitative traits and nitrate concentration of cucumber (Sultan cv.), a factorial hydroponic-experiment with completely randomized design and three replications was conducted in the greenhouse of Soil Science Department, Zanjan University, in 2009. The concentrations of N in nutrient solution were 238 and 310 mg/L, and Mo was used at the rates of 0.01, 0.1 and 1 mg/L. The results showed that the effects of N and Mo levels were significant (P≤0.01) on plant yield and growth indices such as average weight, length and diameter of fruit and chlorophyll content of leaf. The chlorophyll content of leaf increased but fruit yield and average weight, length and diameter of fruits decreased as the N concentration of the nutrient solution increased. Increasing the Mo level in the nutrient solution decreased the growth indices and yield of cucumber. The highest fruit yield was obtained when the concentration of Mo in the nutrient solution was 0.01 mg/L. But it didn’t have significant difference with 0.1 mg/L treatment. However, the yield decreased significantly as the Mo concentration increased to 1 mg/L. The effects of N and Mo levels of nutrient solution were significant (P ≤ 0.01) on nitrate concentration of the fruits. As the N level of nutrient solution increased, the nitrate concentration of cucumber fruit increased from 1356 to 2122 mg/kg (on dry weight basis), and exceeded the toxicity limit of 1500 mg/L. Increasing the concentration of Mo of the nutrient solution from 0.01 to 0.1 mg/L decreased nitrate concentration of fruits from 1961 to 1703 mg/kg, without decreasing the fruit yield. With an increase in N concentration of the nutrient solution, the fruit concentrations of N, potassium and calcium increased, but those of phosphorus, magnesium and Mo decreased significantly. Also, as the concentration of Mo in the nutrient solution increased, the concentrations of iron, manganese and in fruit increased and that of copper decreased.
F. Hosseini, A.h. Khoshgoftarmanesh, M. Afyuni,
Volume 3, Issue 1 (5-2012)
Abstract
Nickel (Ni) is the most recently discovered essential element for higher plants. But there is limited information about the effect of this element on yield and nitrogen (N) metabolism of different plants. In this research, the interaction of Ni supplement and N source was studied on nitrate accumulation and growth of lettuce (Lactuca sativa L. cv. Baker) in solution culture. In a greenhouse experiment, lettuce plants were exposed to two Ni levels (0 and 0.04 µM in the form of NiCl2) and three N levels (5, 10, and 20 µM in the form of urea and ammonium nitrate). The plants were harvested 6 weeks after transplanting and the fresh weight of shoots and roots, total N concentration, nitrate concentration and Fe content of shoots were determined. The results indicated that shoot and root fresh weight of nitrate-fed plants were higher than urea-fed plants. Ni nutrition significantly enhanced the yield of urea-fed plants. The shoot nitrate concentration in nitrate-fed plants was significantly greater in comparison with urea-fed plants. On the other hand, nitrate concentration in the shoots of lettuce plants decreased significantly with Ni nutrition. Ni supplementation in urea-fed plants increased the shoot Fe content. The shoot concentration of total-N in the urea-fed plants increased with the Ni supplement. While, Ni had no significant effect on shoot concentration of total-N in the nitrate-fed plants. Addition of low levels of Ni to the nutrient solution, particularly to the urea-containing solution, improved the yield of lettuce. In addition, these plant leaves are safer for human consumption because the shoot nitrate content is significantly reduced by application of Ni.
H.r. Roosta, N. Rasooli, M.h. Shamshiri,
Volume 3, Issue 3 (11-2012)
Abstract
Due to alkalinity of most soil and water resources in Iran and consequently bicarbonate-induced high pH of plants’ growing medium and different effects of ammonium and nitrate on pH of plant growing medium, research about deleterious effects of factors like alkalinity and interactive effect of nitrogen with bicarbonate on chemical and ecophysiological characteristics of plants seems to be necessary. Thus, an experiment was carried out on snap bean as a factorial trial with completely randomized design and two factors of sodium bicarbonate (0, 1, 5 and 15 mM) and nitrogen form (ammonium and nitrate). The results of this experiment showed that bicarbonate decreased SPAD index and plant pigments in leaves. Proline concentration in ammonium treated plants increased with bicarbonate linearly whereas in nitrate treatment and at 1 mM bicarbonate, it decreased slightly but increased again markedly with elevating of bicarbonate content. In ammonium treatment, the photosynthesis rate, mesophyll efficiency and water use efficiency decreased with bicarbonate, whereas in nitrate treatment, they increased with low and medium concentrations of bicarbonate. It is concluded that in ammonium treatment, bicarbonate decreased photosynthesis efficiency and water utilization in snap bean at all concentrations, whereas, in nitrate-fed plants, bicarbonate at low concentration (1 mM) was suitable, probably due to providing some CO2 or carbon skeleton for nitrogen assimilation in plants.
F. Salighehdar, Sh. Sedaghat-Hor, J. Olfati,
Volume 4, Issue 1 (3-2013)
Abstract
Aloe vera is a perennial liliaceous plant with succulent green leaves joined at the stem in a whorled pattern. It is highly appreciated due to its short growth period and high economic value among all the aloe species, and is used in pharmaceuticals, cosmetic products and food products. In order to improve Aloe vera cultivation in soilless culture, an experiment was conducted in 2011 in greenhouse of College of Agriculture, University of Guilan, Rasht, Iran, as a split plot bi-factorial in completely randomized design with four replications. Four nutrient solutions containing different levels of nitrate and potassium were the main plot, which were sampled at six different periods. Results revealed that the nutrient solutions affect measured traits after 5-6 months. In other words, in research programs for this plant, it is better to record the data for at least 5-6 months. In general, the nutrient solution containing 9.8 mM nitrate and 5.8 mM potassium lead to the best results in all sampling periods. In fact, Aloe vera plants respond positively to high levels of nutrients and in solutions containing the highest level of nitrate and potassium show the highest amount of measured traits.
Z. Gheshlaghi, R. Khorassani, G. H. Haghnia, M. Kafi,
Volume 5, Issue 3 (10-2014)
Abstract
Leafy vegetables play a crucial role in human dietary. Excessive application of nitrogen fertilizer leads to accumulation of high levels of nitrate in the tissues and causes further consequence. In order to evaluate the impact of zinc and harvest times on the reduction of nitrate accumulation and nitrate reductase activity, an experiment was conducted as completely randomized design with factorial arrangement and three replicates in Hoagland and Arnon nutrient solutions. Treatments were two levels of zinc (7 and 50 µg.L-1), two harvest times (29 and 46 days) and two plants of lettuce and spinach. The results indicated that with increasing zinc concentration, nitrate concentration in lettuce shoots in both times decreased and nitrate concentration in roots decreased during the second harvest, whereas no reduction was found in roots and shoots of spinach plants. Nitrate reductase activity was increased in lettuce and spinach plants with application of high zinc levels. Reduced enzyme activity, and increased nitrate accumulation was observed over time in both experimental plants. The results of this study indicated that nitrate metabolism in plants affected by activity of nitrate reductase enzyme, the species of plant, harvest time and plant nutrients such as the zinc.
H. Nazari Mamaqani, S.j. Tabatabaei, S. Bolandnazar,
Volume 6, Issue 4 (1-2016)
Abstract
Nitrate fertilizers are common source of nitrogen (N) in nutrient solutions. Substitution of urea with nitrate could reduce this dependence. Also, nickel (Ni) is essential for activation of urease in plants fed with urea. For this aim, a factorial experiment was conducted in a completely randomized design with four replicates. Urea in five levels (0, 25, 50, 75 and 100 mg/L) and Ni in two levels (0 and 2 mg/L) were used for lettuce (Lactuca sativa cv. Siyahoo) in hydroponics. The results showed that the highest fresh and dry weight of leaves and stem were obtained in 50 mg/L urea treatment. Leaf area was reduced in treatments having more than 25 mg/L urea concentration. The highest chlorophyll index and maximal quantum yield of PS II photochemistry efficiency (Fv/Fm) were obtained in 100 and 75 mg/L urea, respectively. Total nitrogen concentration of leaves was increased significantly with increasing urea concentration; plants treated with 100 mg/L urea had the highest total nitrogen concentration. Nickel application reduced yield and physiological traits of lettuce; while it had no significant effect on total nitrogen concentration.
M. Khalilpour, V. Mozafari ,
Volume 7, Issue 3 (11-2016)
Abstract
In order to evaluate the effect of different levels of benzyladenine, nitrogen and salinity on growth characteristics of pistachio seedlings, cv. Badami Zarand, a factorial experiment with three factors: benzyladenine (0, 250 and 500 mg/L), nitrogen (0 and 100 mg N/kg soil as NH4NO3) and salinity (0 and 2000 mg NaCl/kg soil) was carried out as completely randomized design with three replications for 24 weeks under greenhouse conditions. Results showed that although salinity significantly decreased dry weight of shoots and roots of the seedlings, but application of 500 mg/L benzyladenine increased dry weight of shoots and roots by 125 and 86 percent, respectively. However, simultaneous application of nitrogen and benzyladenine increased dry weight of shoots and roots more than 3 and 2 folds, respectively. Results also showed that salt stress significantly decreased leaf area and length of root system. But simultaneous application of nitrogen and the highest concentration of benzyladenine increased leaf area and length of root system more than 3 and 2.5 folds, respectively. The results of triple effects also showed that although height, leaf number and stem diameter significantly decreased under saline conditions, but simultaneous application of nitrogen and benzyladenine resulted in more prominent increase of these growth characteristics than individual application of these treatments. Finally, it is concluded that simultaneous application of nitrogen and benzyladenine resulted in more effective reduction of harmful effects of salinity on growth characteristics of pistachio seedlings than application of these treatments alone.
A. Estaji, H. R. Roosta, M. Raghami,
Volume 8, Issue 2 (8-2017)
Abstract
Production of medicinal crops in soilless culture systems and controlled environments provides an opportunity for increasing the quantity and quality of primary materials of medicinal plants. A factorial experiment based on completely randomized design was carried out with four culture systems (aeroponics, nutrient film technique, classic hydroponics and soil) and three different nitrogen sources (nitrate, ammonium nitrate and ammonium) and three replications. Results indicated that vegetative traits such as plant height, stem and root diameter, number of lateral branches and leaf area were affected by culture system and source of nitrogen. Plants grown in aeroponics fed by ammonium nitrate had the highest plant height and root and stem diameter. The results also showed that nitrogen source and culture system had significant effect on root dry and fresh weight, shoot dry and fresh weight and root yield per hectare. Maximum and minimum of these parameters were observed in plants fed with ammonium nitrate in aeroponics and ammonium in aeroponics system, respectively. According to the results, ammonium nitrate is recommended as the most proper nitrogen source for production of licorice in aeroponics system.
N. Omidi, N. Aalamzadeh Ansari,
Volume 10, Issue 3 (10-2019)
Abstract
An experiment was conducted as split plot based on the randomized complete blocks design, in greenhouse complex of Shahid Chamran University of Ahvaz in 2017. The main plot consisted of light treatment at two levels [a) sunlight (control), b) sunlight + red and blue LEDs (50:50%) with light intensity of 70 μmol/m2s for 15 hours (from 5 PM to 8 AM as night light] and the subplot was six greenhouse lettuce cultivars (Black Seed Simpson, Green Ice, Vivian, Tom Thumb, Red Salad Bowl and Salad Bowl). Results of the experiment showed that some of the measured traits were influenced by cultivar and light increase and some of them were under the influence of interaction effects of cultivar and light and were significant at 1% level. Maximum fresh and dry weight of leaf, fresh and dry weight of stem, number of leaves and calcium content were observed in night light treatment. Maximum and minimum values of leaf nitrate content were observed in Tom Thumb cultivar and control treatment (1723 μg/g dry weight) and Green Ice cultivar and night light (1023 μg/g dry weight), respectively. Maximum and minimum values of calcium content were observed in Black Seed Simpson cultivar and night light (1477 μg/g dry weight) and Tom Thumb control treatment (271.1 μg/g dry weight), respectively. According to the results of this experiment, by increasing the night light, it is possible to enhance the quantitive growth of the leafy lettuce cultivars by 90%, and also increase the quality of their yield
