Effect of Nitrogen Source on Grain Development in Detached Wheat Heads in Liquid Culture

Detached wheat heads (8 days post anthesis) were grown in liquid culture using media containing various nitrogen sources at different concentrations. Grain development in terms of dry weight, nitrogen, starch and protein were equivalent whether the nitrogen was supplied as either a complete spectrum of amino acids or as glutamine, asparagine or ammonium nitrate. Where the concentration of nitrogen in the culture medium was varied while maintaining the sucrose concentration constant, no variations were observed in the rate of grain dry weight or starch accumulation. Nitrogen per grain and percentage grain nitrogen increased with increasing concentrations of nitrogen in the culture medium. Percentage grain nitrogen was higher in the 'high protein' cultivar Timgalen than in the 'low protein' cultivar WW 15 at equivalent nitrogen concentrations in the culture medium, but differences in percentage proteins were only small.

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Relationship Between Grain Nitrogen, Non-Protein Nitrogen and Nucleic Acids During Wheat Grain Development

Functional Plant Biology ◽

10.1071/pp9790449 ◽

1979 ◽

Vol 6 (4) ◽

pp. 449 ◽

Cited By ~ 5

Author(s):

GR Donovan

Keyword(s):

Total Nitrogen ◽

Culture Medium ◽

Nitrogen Concentration ◽

Dry Weight ◽

Grain Development ◽

Fresh Weight ◽

Wheat Varieties ◽

Protein Nitrogen ◽

Apparent Relationship ◽

Grain Nitrogen

Eight wheat varieties which normally produce grain of different final percentage nitrogen content were grown under field and glasshouse conditions. The final percentage grain nitrogen of the field grown varieties ranked in the expected order; however, total nitrogen/grain, DNAIgrain, RNA/grain and non-protein nitrogen/grain during grain development differed between varieties. DNA/grain reached a maximum value in all varieties between 21 and 28 days post- anthesis, suggesting a longer period of cell division than previously reported. There was no apparent relationship between final percentage grain nitrogen and either DNA, total grain RNA or the concentration of grain amino acids during development. Heads from glasshouse grown wheat were detached at 8 days postanthesis and grown in liquid culture under conditions where the nitrogen concentration of the culture medium was varied. Fresh weight/grain, DNA/grain, RNA/grain and total grain nitrogen all increased with increasing nitrogen concentration in the culture medium, but grain dry weight remained constant at the different nitrogen concentrations. The changes in fresh weight/grain, DNA/grain and RNA/grain were not the same for all varieties. A possible relationship between total grain nitrogen and DNA/grain and RNA/grain during seed development exists for heads grown in culture for individual varieties. This apparent relationship for individual varieties cannot be used to explain intervarietal differences in total grain nitrogen because in some cases different varieties grown under identical culture conditions, although producing grain of equivalent total nitrogen, had widely differing levels of both DNA and RNA per grain.

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Water Relations and Composition of Wheat Ears Grown in Liquid Culture: Effect of Carbon and Nitrogen

Functional Plant Biology ◽

10.1071/pp9830099 ◽

1983 ◽

Vol 10 (1) ◽

pp. 99 ◽

Cited By ~ 25

Author(s):

EWR Barlow ◽

GR Donovan ◽

JW Lee

Keyword(s):

Liquid Culture ◽

Culture Medium ◽

Culture Media ◽

Sucrose Concentration ◽

Soluble Sugar ◽

Soluble Sugars ◽

Protein Nitrogen ◽

Protein Levels ◽

Grain Starch ◽

Osmotic Potentials

Detached wheat ears were grown, under lighted controlled conditions, in liquid culture media containing different concentrations of sucrose and amino acid. Higher levels of sucrose in the culture medium resulted in decreased transpiration, with large accumulations of soluble sugar in the bracts. The sugar accumulations led to decreased total and osmotic potentials of the bracts, but turgor was maintained or increased. The concentration of sucrose or nitrogen in the culture medium had no significant effect on the water or osmotic potentials of the grain. Soluble sugar concentrations in the grain were not affected by increasing the sucrose concentration in the culture medium. Increasing the nitrogen level in the culture medium led to increased concentrations of total nitrogen and non- protein nitrogen in the grain. Higher protein levels in the grain resulted in increased water content but no significant changes in the water potential of the grain. The grain was the strongest nitrogen sink within the ear and, within the grain, starch and protein synthesis were independent of each other. Proline accumulated in the bracts and to a lesser extent in the rachis in response to the accumulation of soluble sugars and nitrogen rather than to the low osmotic or total water potentials. Little proline accumulated in the grain and this was presumed to be due to translocation from other parts of the ear rather than to in situ synthesis.

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Biochemical transformations of herbicide-derived anilines in culture medium and in soil

Canadian Journal of Microbiology ◽

10.1139/m72-290 ◽

1972 ◽

Vol 18 (12) ◽

pp. 1857-1864 ◽

Cited By ~ 19

Author(s):

L. M. Bordeleau ◽

R. Bartha

Keyword(s):

Peroxidase Activity ◽

Microbial Growth ◽

Culture Medium ◽

Nitrogen Sources ◽

Dry Weight ◽

Geotrichum Candidum ◽

Soil Extract ◽

Breakdown Product ◽

Mineral Salts ◽

Carbon And Nitrogen

A correlation was established between peroxidase activity of soil and its capacity to transform 3,4-dichloroaniline, a breakdown product of several herbicides, to 3,3′,4,4′-tetrachloroazobenzene. Supplementation of soil by carbon and nitrogen sources for microbial growth stimulated both activities, and pointed to the microbial origin of soil peroxidases. Several peroxidase-producing bacteria, actinomycetes, and fungi were isolated from soil and were characterized. On the basis of its rapid growth and high peroxidase activity, a Geotrichum candidum strain was selected for further study. The culture filtrate of this organism exhibited both peroxidase and aniline oxidase activity. The highest per milligram dry weight activity of these enzymes was observed after cultivation on a mineral salts medium supplemented with soil extract and yeast extract.

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Orchid in vitro growth as affected by nitrogen levels in the culture medium

Horticultura Brasileira ◽

10.1590/s0102-05362012000100020 ◽

2012 ◽

Vol 30 (1) ◽

pp. 119-124 ◽

Cited By ~ 2

Author(s):

Armando R Tavares ◽

Jorge Luiz M Young ◽

Sandra S Ori ◽

Shoey Kanashiro ◽

Giuseppina PP Lima ◽

...

Keyword(s):

Culture Medium ◽

Culture Media ◽

Nitrogen Concentration ◽

Dry Weight ◽

In Vitro Cultivation ◽

Ionic Balance ◽

In Vitro Growth ◽

Nitrogen Levels ◽

Nitrogen Concentrations

In vitro cultivation is the main propagation method for the family Orchidaceae, whereas nitrogen is the most important nutrient in the culture media. This work was carried out to study the influence of different nitrogen concentrations on the in vitro growth of the orchid Phalaenopsis amabilis. Nitrogen concentrations varied by altering the ionic balance of the Murashige & Skoog (MS) culture medium. Plants, 360 days old, were cultivated in liquid MS, modified with 7.5, 15, 30, 45, and 60 mM N. After 180 days, we assessed plant and root length, number of leaves and roots, and fresh and dry weight of leaves, roots and plants. Treatments were assigned to completely randomized plots, with four replications. Plots consisted of five three-plant flasks. The lowest nitrogen level (7.5 mM) in the medium induced root development in length, number, and fresh and dry weight. The concentration 30 mM N stimulated both emission and dry weight accumulation of leaves. The original nitrogen concentration in the MS medium (60 mM) was excessive for the in vitro growth of P. amabilis.

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BIOSYNTHESIS OF RIBOFLAVIN BY EREMOTHECIUM ASHBYII: IX. GROWTH AND RIBOFLAVIN FORMATION AND THEIR RELATION TO THE UTILIZATION AND ASSIMILATION OF THE CONSTITUENTS OF THE LIQUID CULTURE MEDIA

Canadian Journal of Microbiology ◽

10.1139/m65-083 ◽

1965 ◽

Vol 11 (4) ◽

pp. 625-628 ◽

Cited By ~ 2

Author(s):

H. G. Osman ◽

M. S. Chenouda

Keyword(s):

Carbon Source ◽

Total Nitrogen ◽

Lipid Content ◽

Liquid Culture ◽

Culture Medium ◽

Culture Media ◽

Total Lipid Content ◽

Dry Weight ◽

Mature Stage ◽

Lactic Acids

The major amount of riboflavin is formed when the mycelia reach a mature stage and the major carbon source is almost exhausted. While the riboflavin is being synthesized in larger quantities, the mycelial dry weight, the total nitrogen, and total lipid content decrease. The mobilized cell reserves may be those components which call upon the biosynthesis of the major amount of the vitamin. At the stage of growth where glucose is almost completely utilized an increase in the excretion of pyruvic and lactic acids from the mycelia into the culture medium occurs. This may partly explain the increase in the acidity of the culture medium at that stage.

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Nitrification: an old process, a new concern

Silva Gandavensis ◽

10.21825/sg.v24i0.997 ◽

1971 ◽

Vol 24 ◽

Author(s):

W. H. Verstraete

Keyword(s):

Culture Medium ◽

Nitrogen Sources ◽

Living Cells ◽

Factors Affecting ◽

Inhibiting Effect ◽

Proteose Peptone ◽

Asparaginase Activity

Some factors affecting the L-asparaginase activity of E. aroideae were investigated. Increasing concentrations of glucose in the culture medium had an inhibiting effect on the production of L-asparaginase by this microorganism. Buffering of the culture medium in order to stabilize the pH during growth resulted in a decrease of the L-asparaginase activity. From the different nitrogen sources examined, tryptone, proteose peptone nr 2 and nr 3 stimulated the L-asparaginase production. Toluene treatment of the cells practically destroyed the L-asparaginase. Acetone dried cells showed an L-asparaginase activity comparable with the activity of living cells.

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The effect of meal composition on the degree of satiation following a test meal and possible mechanisms involved

British Journal Of Nutrition ◽

10.1079/bjn19880116 ◽

1988 ◽

Vol 60 (3) ◽

pp. 441-449 ◽

Cited By ~ 25

Author(s):

Christopher J. I. Driver

Keyword(s):

Time Course ◽

Dry Weight ◽

High Fat ◽

Point Scale ◽

Protein Meal ◽

Low Protein ◽

Gut Hormone ◽

High Protein Meal ◽

Milk Solids ◽

Meal Composition

1. Possible links between metabolism and satiation were investigated using volunteer subjects given test meals based on milk solids. Satisfaction was rated by the subjects on a six-point scale and the course of metabolism was followed by measurement of the respiratory quotient (RQ).2. The time-course of satiation was the same for a high-carbohydrate, a high-fat and a high-protein meal, in spite of the very different time-course of metabolism. The degree of satiation was reduced by added sodium chloride, without affecting the RQ rise. On the other hand, calcium chloride produced a suppression of the RQ rise without altering the satiation.3. It is proposed that the results indicate that the primary receptors responsible for post-prandial satiation lie within the gut wall and that there is probably a number of receptor types. Likely candidates for these receptors are the gut hormone-secreting cells.4. Although very-low-protein meals produce less satiation than meals containing 220 g protein/kg dry weight, there is no additional satiation obtained by increasing the protein level further. This is not inconsistent with the possibility of a protein hunger separate from an energy hunger.

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Immunological discrimination between a sap-staining fungus and a biological control fungus

Canadian Journal of Botany ◽

10.1139/b90-203 ◽

1990 ◽

Vol 68 (7) ◽

pp. 1578-1588 ◽

Cited By ~ 4

Author(s):

Brian T. Luck ◽

Colette Breuil ◽

David L. Brown

Keyword(s):

Electron Microscopy ◽

Biological Control ◽

Immunosorbent Assay ◽

Liquid Culture ◽

Biological Control Agent ◽

Dry Weight ◽

Cross Reactivity ◽

Immunogold Labeling ◽

Enzyme Linked Immunosorbent Assay ◽

Polyclonal Serum

An enzyme-linked immunosorbent assay (ELISA) was used to detect a sap-staining fungus, Ophiostoma piceae, and a biological-control agent, Gliocladium roseum, grown in liquid culture and in wood. A polyclonal serum prepared against whole cell fragments from broken mycelia of O. piceae detected O. piceae in liquid culture at 0.25 μg dry weight/mL; however, there was moderate cross-reactivity with G. roseum. Antiserum adsorbed on G. roseum had almost no reactivity with G. roseum but still reacted strongly with O. piceae. The specificity of these sera was verified, and the antigenic sites were localized, by immunogold labeling and electron microscopy. These studies confirmed that the adsorbed serum could differentiate between G. roseum and O. piceae and showed that the cell wall was the most reactive cellular component. These results are discussed in relation to the development of immunological probes for the detection of sap-staining and biological control fungi. Key words: polyclonal serum, enzyme-linked immunosorbent assay, immunogold labeling, sap-staining and biological control fungi, electron microscopy.

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Nitrogen, Phosphorus and Water Contents During Grain Development and Maturation in Wheat

Functional Plant Biology ◽

10.1071/pp9770799 ◽

1977 ◽

Vol 4 (5) ◽

pp. 799 ◽

Cited By ~ 57

Author(s):

I Sofield ◽

IF Wardlaw ◽

LT Evans ◽

SY Zee

Keyword(s):

Grain Growth ◽

Dry Matter ◽

Nitrogen Concentration ◽

Growth Period ◽

Calcium Content ◽

Dry Weight ◽

Water Entry ◽

Grain Development ◽

Nitrogen And Phosphorus ◽

Steady Rate

Plants of five cultivars of wheat were grown under controlled-environmental conditions in order to analyse the effect of cultivar and of temperature and illuminance after anthesis on the accumulation of nitrogen and phosphorus by grains in relation to dry matter. The water relations of the grain during maturation were also examined, using calcium content as an index of water entry. The nitrogen and phosphorus contents of grains increased linearly throughout the grain growth period. The percentage of nitrogen and phosphorus in grains fell sharply during the first few days after anthesis but rose progressively thereafter. The higher the temperature, and the lower the illuminance, the higher was the percentage of nitrogen in the grain of all cultivars. Such conditions also reduce final grain size, but their effects on nitrogen concentration in the grain were apparent early in grain development. No evidence was found of a flush of nitrogen or phosphorus into the grain late in its development. Water entry into the grain continued at a steady rate until maximum grain dry weight was reached, then ceased suddenly. No evidence was found of an increased rate of water loss by the grain at that stage, and the rapid fall in water content at the cessation of grain growth may have been due to blockage of the chalazal zone of entry into the grain by the deposition of lipids. Accumulation of dry matter, nitrogen and phosphorus and entry of water into the grain all ceased at the time of lipid deposition in the chalazal zone.

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