Influence of nitrogen nutrition and watering regime on the nitrogen concentration and quality of tobacco leaves

1974 ◽  
Vol 14 (70) ◽  
pp. 671 ◽  
Author(s):  
AD Johnson ◽  
RW Knowlton
Keyword(s):  
Nitrogen Nutrition ◽  
Nitrogen Concentration ◽  
Dry Weight ◽  
Leaf Nitrogen ◽  
Nitrogen Application ◽  
Split Application ◽  
Leaf Quality ◽  
Tobacco Leaves ◽  
High Concentrations ◽  
Applied Nitrogen

The effects of different levels of applied nitrogen, times of application of nitrogen and watering regimes on the nitrogen concentration of tobacco leaves, were studied in a series of glasshouse experiments. Time of nitrogen application was also studied in the field. Increasing the nitrogen supply increased dry weight and area of leaves but did not produce an increase in nitrogen concentration of leaves especially in the middle plant position. A significant increase in nitrogen concentration of leaves in the middle plant position was achieved by either split application of nitrogen or by imposing a regular watering stress during growth. The restricted watering treatment also reduced dry weight and area of leaves. Relatively high concentrations of nitrogen in the upper leaves resulted from late application of nitrogen and an experiment using labelled nitrogen confirmed that most late applied nitrogen was incorporated into upper leaves. Changes in leaf nitrogen concentration from time of removal of the inflorescence to final harvest are shown. A field experiment confirmed the glasshouse findings on time of nitrogen application and permitted cured leaf quality assessments to be made. Best leaf quality was produced by split application of nitrogen

scholarly journals Cytogenotoxic effects of nitrogen on hydroponic lettuce

2020 ◽  
Vol 36 ◽  
Author(s):  
Alcione da Silva Arruda ◽  
Wesley Costa Silva ◽  
Roberta Camargos de Oliveira ◽  
Ernane Miranda Lemes ◽  
Gabriela da Silva Guimarães ◽  
...  
Keyword(s):  
Nitrogen Concentration ◽  
Calcium Nitrate ◽  
Dry Weight ◽  
Positive Control ◽  
Leaf Nitrogen ◽  
Nitrogen Accumulation ◽  
Fresh Weight ◽  
Shoot Dry Weight ◽  
Nutrient Film Technique ◽  
Nitrogen Concentrations

Nitrogen accumulation in hydroponically-grown lettuce may pose a health risk to consumers. Thus, the objective of this study was to analyze different concentrations of nitrogen applications in hydroponic lettuce cultivation and their effect on toxicity, cytotoxicity and genotoxicity. A nutrient film technique (NFT) hydroponic system was used to grow the lettuce variety “Vanda.” The treatments consisted of different concentrations of nitrogen (in the form of calcium nitrate) in Furlani solution (75, 100, 125 and 150%), a negative and a positive control. The following commercial characteristics were measured: plant fresh weight (PFW), root fresh weight (RFW), shoot fresh weight (SFW), shoot diameter (SD), root dry weight (RDW), shoot dry weight (SDW) and leaf nitrogen (LN). Cytogenotoxicity was indicated by toxicity, cytotoxicity and genotoxicity, which were in turn determined by root length, the mitotic index, chromosomal aberrations and the presence of micronuclei.  The nitrogen concentrations used in this experiment did not cause phenotypic toxicity or cytotoxicity in lettuce roots. The most severe genotoxicity was observed at the 125% nitrogen concentration, which nevertheless did not affect commercial characteristics. Although nitrogen fertilization provides great benefits to agriculture, such as greater yields, indiscriminate use should be avoided since concentrations above recommended rates may induce genotoxicity.

Effects of harvesting programme and sowing date on the forage yield, digestibility, nitrogen concentration, tillers and crop fractions of barley in Cyprus

1987 ◽  
Vol 109 (1) ◽  
pp. 95-106 ◽  
Author(s):  
D. N. Droushiotis ◽  
D. Wilman
Keyword(s):  
Field Experiments ◽  
Nitrogen Concentration ◽  
Leaf Nitrogen ◽  
Forage Yield ◽  
Green Leaf ◽  
Dead Leaf ◽  
Boot Stage ◽  
Nitrate N ◽  
Sowing Dates ◽  
Applied Nitrogen

SummaryAll combinations of four harvesting treatments and two sowing dates were comparedin each of 3 years in field experiments near Nicosia. In two of the years, different levels of applied nitrogen were compared. The harvesting treatments were: (1) a milk-stage cut,(2) a boot-stage cut and a regrowth cut, (3) a grazing-stage cut and a regrowth cut, and(4) three grazing-stage cuts and a regrowth cut. The sowing dates were (1) normal (12 November) and (2) early (15 October), with sufficient irrigation to ensure establishment. There was almost no response to applied nitrogen, evidently because of high reserves of available nitrogen in the soil. Early sowing reduced by 20 days the time taken to reach the stage at which the first node appeared, but increased, by 36 days, the length of time between the first node and the milk stage. Early sowing increased yield when the firstcut was at the grazing stage, but reduced yield when the first cut was at the boot or milk stage. At the grazing stage, the proportion of green leaf blade and the concentrations of nitrogen and nitrate-N were relatively high (means 74, 4·0 and 0·13% respectively) and digestibility was moderate (mean D-value 61). By the boot stage, green leaf, nitrogen and nitrate-N, but not digestibility, had declined (means 21, 1·8, 0·02 and 63 respectively). By the milk stage, green leaf, nitrogen and digestibility, but not nitrate-N, had declined further (means 3, 1·5, 48 and 0·05 respectively). Fully dead leaf blades were 28 units less digestible and 3·2 percentage units lower in nitrogen concentration than emerging leaves. Half dead leaf blades were higher in nitrate-N than fully expanded, fully green blades. 'Stem’ declined greatly in nitrogen concentration, but relatively little in digestibility, between the grazing and the boot stage.Crops cut once or three times at a grazing stage recovered well, although theretended to be some reduction in the number of tillers compared with an undefoliated crop.

Quality of fresh and dried fruit of apricot (cv. Moorpark) in response to soil-applied nitrogen

2006 ◽  
Vol 46 (1) ◽  
pp. 123 ◽  
Author(s):  
M. A. Rettke ◽  
T. R. Pitt ◽  
N. A. Maier ◽  
J. A. Jones
Keyword(s):  
Sulfur Dioxide ◽  
Block Design ◽  
Nitrogen Concentration ◽  
South Australia ◽  
Prunus Armeniaca ◽  
Soluble Solids ◽  
Nitrogen Application ◽  
Dried Fruit ◽  
Applied Nitrogen

The effects of soil applications of nitrogen on the quality of fresh and dried fruit from 12-year-old apricot Prunus armeniaca cultivar Moorpark trees growing on an orthic Tenosol in the Riverland region of South Australia were studied over 3 years. The experiment was set up in a randomised complete block design with 6 annual rates of nitrogen (0, 250, 500, 750, 1000 and 1250 g/tree.year) applied in the form of ammonium nitrate. Application was split into 30% at budburst, 30% six weeks after budburst and 40% after harvest. Firmness of fruit was significantly reduced as the rate of applied nitrogen increased. The flesh of individual fruits ripened more evenly when 0 or 250 g nitrogen/tree.year was applied, compared with rates in the range 500–1250 g nitrogen/tree.year. Application of nitrogen significantly increased the pH of fruit. The total soluble solids level of fruit from trees that received 0 or 250 g nitrogen/tree.year, was significantly lower than from trees that received 750 or 1250, but not 1000 g nitrogen/tree.year. Application of nitrogen did not significantly affect the concentration of sulfur dioxide in fresh fruit measured after sulfuring, but the concentration of sulfur dioxide in fruit at the completion of drying was significantly increased. The application of nitrogen did not affect the drying ratio of fruit. Nitrogen application increased the rate of darkening of dried apricots in storage in each of the three years. Relationships were found between time taken for dried apricots to darken to an unacceptable level and nitrogen concentration in harvested fruit. It is suggested that to assist in the management of darkening of dried apricots in storage, annual nitrogen application rates on an orthic Tenosol need to be below 500 g/tree.year and ideally below 250 g/tree.year.

Effect of seed weight, and seed phosphorus and nitrogen concentrations on the early growth of wheat seedlings

1990 ◽  
Vol 30 (4) ◽  
pp. 545 ◽  
Author(s):  
DGDe Marco ◽  
Marco DG De
Keyword(s):  
Seed Weight ◽  
Nitrogen Concentration ◽  
Seedling Emergence ◽  
Dry Weight ◽  
Early Growth ◽  
Sand Culture ◽  
Wheat Seedlings ◽  
P Content ◽  
Nitrogen Concentrations ◽  
High Concentrations

Wheat seeds of uniform weight selected from 3 batches of seed with phosphorus (P) concentrations of 0.14, 0.17 and 0.19% were sown in soil with a range of applied P treatments. Seedling emergence was more rapid the higher the seed P. By 25 days after sowing all plants grown at the highest concentration of applied P were similar in size, but with lower applied P, plants from seed with higher P concentrations had an advantage. A range of weight classes was selected from 2 batches of seed raised at low or high concentrations of P. There were 11 groups ranging in mean seed weight from 28 to 58 mg and in seed P from 0.13 to 0.37%. Seedlings from the high P batch had larger first leaves, a higher dry weight, and longer roots than those from the low P batch when grown in a highly P-deficient sand culture system. Within each batch, heavier seeds produced larger leaves, heavier plants and longer roots. The yield differences between batches were largely accounted for if the seed P content (�g P/seed) was considered rather than either percentage P or seed weight alone. Differences in seed nitrogen concentration or content did not consistently account for differences in seedling growth.

scholarly journals NITROGEN NUTRITION AND SEEDLING DEVELOPMENT OF NORMAL AND OPAQUE-2 MAIZE GENOTYPES

1984 ◽  
Vol 64 (4) ◽  
pp. 885-894 ◽  
Author(s):  
SANGITA HANDA ◽  
H. L. WARREN ◽  
D. M. HUBER ◽  
C. Y. TSAI
Keyword(s):  
Glutamine Synthetase ◽  
Glutamate Dehydrogenase ◽  
Nitrogen Nutrition ◽  
Dry Weight ◽  
Synthetase Activity ◽  
Glutamine Synthetase Activity ◽  
Glutamate Dehydrogenase Activity ◽  
Early Seedling ◽  
High Concentrations ◽  
Normal Genotype

Early seedling growth and glutamine synthetase and glutamate dehydrogenase activities of the normal and opague-2 (o2) genotypes of maize were compared in the presence or absence of added N. In the absence of exogenous N, the dry weight of o2 seedlings was only 60% of the dry weight of normal seedlings at 21 days after germination; however, the dry weights were comparable when exogenous N, especially as NO−3, was supplied to both genotypes. Thus, exogenous N appears to be more critical for early growth of o2 than normal seedlings. Growth of o2 seedlings was more severely restricted than of the normal genotype by high concentrations of NH+4. A combination of NH+4 and NO−3 resulted in better growth of both genotypes than either form on N alone. There was no difference in the capacity of the two genotypes to accumulate N from exogenous NH+4 or NO−3. However, both genotypes accumulated relatively more N from NH+4 than from NO−3. Glutamine synthetase activity in o2 roots was twofold higher than in the normal genotype in the absence of exogenous N but was similar in the roots of both gentoypes when seedlings were grown in either NO−3 or NH+4. In the absence of exogenous N, glutamate dehydrogenase activity in o2 roots was 2.8-fold higher than in normal roots and remained higher when NH+4 was added.Key words: Nitrogen form, ammonium, nitrate, glutamate dehydrogenase, glutamine synthetase, zein

scholarly journals Nitrogen Nutrition of Containerized Anemone x hybrida

2000 ◽  
Vol 18 (3) ◽  
pp. 145-148
Author(s):  
Jean-Jacques B. Dubois ◽  
Stuart L. Warren ◽  
Frank A. Blazich
Keyword(s):  
Leaf Area ◽  
Nitrogen Nutrition ◽  
Dry Weight ◽  
Nitrogen Application ◽  
Constant Ratio ◽  
Application Rates ◽  
Single Crown ◽  
Top Dry Weight ◽  
Complete Nutrient Solution ◽  
Propagation Material

Abstract Uniform single crown plantlets of Anemone x hybrida Paxton ‘Margarete’ were grown in 3.8-liter (#1) containers filled with a substrate of composted pine bark:sand (8:1 by vol). Plants were fertilized three times weekly for 15 weeks with a complete nutrient solution at nitrogen application rates (NARs) of 10, 40, 80, 150 or 300 mg/liter (ppm) nitrogen (N), in a constant ratio of 1 ammonium:2 nitrate. All other nutrients were held constant. Leaf area, top dry weight, and root dry weight increased with increasing NAR until reaching a plateau at a NAR of 144 ± 21 mg/liter (ppm), 158 ± 28 mg/liter (ppm), and 119 ± 30 mg/liter (ppm), respectively. The proportion of fine roots to thick roots was unaffected, and production of propagation material (root cuttings) reached a plateau at a NAR of 108 ± 28 mg/liter (ppm). Leaf concentrations of N, P, and K at maximum leaf area were 4.7%, 0.5%, and 3.5%, respectively.

The effect of application of genistein to Bradyrhizobium japonicum culture and its rooting medium on soyabean growth nodulation and nitrogen assimilation in the presence of nitrate

2000 ◽  
Vol 135 (1) ◽  
pp. 19-25
Author(s):  
B. PAN ◽  
D. L. SMITH
Keyword(s):  
Nitrogen Assimilation ◽  
Nitrogen Concentration ◽  
Dry Weight ◽  
Leaf Nitrogen ◽  
Root Extracts ◽  
Randomized Design ◽  
Rooting Medium ◽  
Nitrogen Concentrations ◽  
Completely Randomized Design ◽  
Nitrogen Contents

In the soyabean [Glycine max (L.) Merr.]–B. japonicum symbiosis, genistein has been identified as one of the major compounds in soyabean seed and root extracts responsible for inducing the expression of the B. japonicum nod genes. High combined nitrogen in the growth medium inhibits nodulation and nitrogen assimilation. Two experiments were conducted to test the possibility of overcoming this inhibition by adding genistein to the rooting medium and by incubation of B. japonicum cells with genistein. One soyabean cultivar was used in the first experiment, and two in the second experiment. The experiments were conducted in a glasshouse using a completely randomized design with three rooting medium nitrate concentrations (0, 5 and 10 mM) and four genistein treatments. The genistein treatments were 0 (control), incubation of B. japonicum cells with 5 μM genistein, and regular watering with 5 μM or 20 μM genistein. A two way interaction existed in the first experiment, and two and three way interactions existed in the second experiment. Root growth was inhibited by repeated watering with 20 μM genistein. Weight per nodule was greater at 5 mM than at 0 mM nitrate. At 10 mM nitrate watering with genistein resulted in significant increases in nodule dry weight per plant. Shoot nitrogen contents were significantly increased at 5 mM nitrate by genistein incubation and watering with 20 μM genistein. Watering with 5 μM genistein significantly increased nodule nitrogen concentrations at both 5 and 10 mM nitrate. The two soyabean cultivars responded differently to the genistein and nitrate treatments in terms of nodule number, nodule weight, leaf nitrogen concentration and nodule nitrogen content. Genistein could, at least partially, overcome the inhibition of soyabean nodulation and nitrogen assimilation by nitrate.

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