Studies on morphogenesis in a blue-green alga. I. Effect of inorganic nitrogen sources on developmental morphology of Anabaena doliolum

1968 ◽  
Vol 14 (12) ◽  
pp. 1341-1346 ◽  
Author(s):  
H. N. Singh ◽  
B. S. Srivastava
Keyword(s):  
Inorganic Nitrogen ◽  
Basal Medium ◽  
Nitrogen Sources ◽  
Spatial Relations ◽  
Ammonium Nitrogen ◽  
Developmental Cycle ◽  
Developmental Morphology ◽  
Anabaena Doliolum ◽  
Complete Lysis ◽  
Nitrate And Nitrite

Spore germination, heterocyst production, hormogone formation, and sporulation are the morphogenetic stages in the developmental cycle of Anabaena doliolum Bharadwaja. In basal medium sporulation is simultaneous while heterocyst formation is sequential. Nitrate, nitrite, and ammonium nitrogen inhibit sporulation and heterocyst formation. The degree of inhibition depends on the concentration and source of inorganic nitrogen. Nitrate and nitrite induce lysis which is concentration dependent and circumscribed by time, i.e., up to a certain stage the lytic events are preventable by transfer to basal medium, but beyond this stage they become inevitable and complete lysis occurs even in the absence of nitrate or nitrite. The sequential differentiation and spatial relations of heterocysts in a growing filament are characteristic of each nitrogen source and indicative of the polarity involved in the gradient of heterocyst formation.

EFFECT OF AMMONIUM NITROGEN AND AMINO ACIDS ON PERITHECIAL FORMATION OF VENTURIA INAEQUALIS

1971 ◽  
Vol 51 (1) ◽  
pp. 29-33 ◽  
Author(s):  
R. G. ROSS ◽  
FRANCES D. J. BREMNER
Keyword(s):  
Amino Acids ◽  
Ammonium Carbonate ◽  
Venturia Inaequalis ◽  
Amino Nitrogen ◽  
Basal Medium ◽  
Nitrogen Sources ◽  
Ammonium Nitrogen ◽  
Racemic Mixture ◽  
Appreciable Change ◽  
The Media

Perithecia of Venturia inaequalis did not form in a basal medium to which was added ammonium sulfate, chloride, phosphate or tartrate as the sole sources of nitrogen, when the pH of the medium was allowed to fall to inhibitory levels. Perithecia formed with these ammonium salts as nitrogen sources when calcium carbonate was added to control the pH. With ammonium carbonate and oxalate there was no appreciable change in pH, and perithecia formed with these salts as nitrogen sources. Perithecia did not form in media with leucine as a nitrogen source. Formation of perithecia with other amino acids depended on the concentration of amino-nitrogen in the media. A substance toxic to perithecial formation may form in cultures containing leucine; if so, it is produced in different amounts by the two isomers and the racemic mixture of this amino acid.

scholarly journals Effects of carbon and nitrogen sources on production of proteases by Bacillus subtilis IC-5

2018 ◽  
Vol 44 (2) ◽  
pp. 285-292
Author(s):  
Sereen Gul ◽  
Mujeeb Ur Rahman ◽  
Mohammad Ajmal ◽  
Abdul Kabir Khan Achakzai ◽  
Asim Iqbal
Keyword(s):  
Bacillus Subtilis ◽  
Sodium Nitrate ◽  
Inorganic Nitrogen ◽  
Carbon Sources ◽  
Basal Medium ◽  
Nitrogen Sources ◽  
Neutral Protease ◽  
Carbon And Nitrogen Sources ◽  
Inorganic Nitrogen Source ◽  
Carbon And Nitrogen

The effects of various carbon and nitrogen sources were evaluated on production of proteases by Bacillus subtilis IC-5. Both type and concentration of carbon and nitrogen sources influenced the production of proteases. Among the carbon sources glucose was found to be the most effective. It gave maximum production at 2% w/v concentration i.e., 1875 and 950 U/ml, alkaline and neutral protease, respectively. The response of Bacillus subtilis IC-5 towards synthesis and excretion of enzymes varied with the type of nitrogen sources. The addition of organic nitrogen sources to basal medium repressed the synthesis of proteases while the addition of inorganic nitrogen source such as sodium nitrate was found to be the best stimulating for alkaline and neutral protease synthesis. Sodium nitrate enhanced the production up to 62.40 and 10.52% of alkaline and neutral protease, respectively against w.r.t. control.

Effects of nitrogenous compounds on sclerotium formation in Aspergillus niger

1968 ◽  
Vol 14 (11) ◽  
pp. 1253-1258 ◽  
Author(s):  
V. P. Agnihotri
Keyword(s):  
Amino Acids ◽  
Aspergillus Niger ◽  
Basal Medium ◽  
Nitrogen Sources ◽  
Dry Weight ◽  
Ammonium Nitrogen ◽  
Nitrogenous Compounds ◽  
Alkaline Side ◽  
Sclerotium Formation ◽  
Ammonium Compounds

The effects of different nitrogen sources on growth and sclerotial production by Aspergillus niger were determined on a synthetic agar medium. The organism used inorganic, organic, and ammonium nitrogen for growth and sclerotial production. Among the ammonium compounds tested, the chloride, phosphate, sulfate, and carbonate were used poorly, but the nitrate was well utilized. Addition of organic acids to ammonium compounds increased sclerotial production. Raising the concentration of sodium nitrate to a certain level (0.15%) increased the number of sclerotial initials and the number and weight of those which matured. Sodium nitrite curtailed mycelial growth and prevented production of sclerotia. Utilization of nitrite was accelerated by adjusting the pH on the alkaline side from 7.5 to 9.0. Urea supported poor sclerotial production; thiourea inhibited it. Of the amino acids, histidine yielded the most and arginine the least number of sclerotia. In lysine medium, the white cottony sclerotial initials remained fluffy even after 20 days. Sclerotial production decreased significantly when proline, glutamic acid, or leucine were omitted from the basal medium containing 10 amino acids. In general, no correlation existed between the number of sclerotia formed and the dry weight they attained on different nitrogen sources. With certain nitrogen sources sclerotial initials failed to mature.

Nitrogen cycling in a Venezuelan tropical seasonally flooded forest: soil nitrogen mineralization and nitrification

1994 ◽  
Vol 10 (3) ◽  
pp. 399-416 ◽  
Author(s):  
Barrios E. ◽  
Herrera R.
Keyword(s):  
Soil Nitrogen ◽  
Nitrogen Availability ◽  
Inorganic Nitrogen ◽  
Nitrogen Concentration ◽  
Ammonium Nitrogen ◽  
Wet Season ◽  
Flooded Forest ◽  
Nitrogen Concentrations ◽  
Minimum Stress ◽  
Seasonally Flooded

ABSTRACTSeasonally flooded forests represent a transition between terrestrial and aquatic ecosystems. The Mapire river, a tributary of the Orinoco river, floods its surrounding forests during the wet season (May–December). The soils are very acid and the total nitrogen concentration (0.1%) is only half that found in nearby soils flooded by Orinoco waters. Ammonium-nitrogen predominates in the soil during the flooded period while nitrate-nitrogen concentrations are higher in the dry period. Wide fluctuations in the inorganic nitrogen fractions did not considerably affect the annual course of soil nitrogen.The predominance of mineralization versus nitrification (56 and 5 μgsoil month−1respectively) and possibly the synchronization of nitrogen availability with plant demand could be considered as nitrogen conserving mechanisms.In synchrony with the hydrologic cycle, the seasonally flooded forest studied shows a nitrogencycle where inputs and accumulation are maximized when the system is under minimum stress (dry season). During flooding, the system enters a period of dormancy making minimal use of nutrient and energy to avoid or tolerate anaerobiosis.

Comparison of Organic and Inorganic Nitrogen Sources for Rice 1

1987 ◽  
Vol 79 (5) ◽  
pp. 937-943 ◽  
Author(s):  
M. P. Westcott ◽  
D. S. Mikkelsen
Keyword(s):  
Inorganic Nitrogen ◽  
Nitrogen Sources

scholarly journals Medium Optimization for Spore Production of a Straw-Cellulose Degrading Actinomyces Strain under Solid-State Fermentation Using Response Surface Method

2020 ◽  
Vol 12 (21) ◽  
pp. 8893
Author(s):  
Huanran Liu ◽  
Dan Zhang ◽  
Xia Zhang ◽  
Chuanzhi Zhou ◽  
Pei Zhou ◽  
...  
Keyword(s):  
Solid State ◽  
Solid State Fermentation ◽  
Inorganic Nitrogen ◽  
Nitrogen Sources ◽  
Spore Production ◽  
Steepest Ascent ◽  
Medium Components ◽  
Burman Design ◽  
Plackett Burman Design ◽  
Central Composite

The strains capable of degrading cellulose have attracted much interest because of their applications in straw resource utilization in solid-state fermentation (SSF). However, achieving high spore production in SSF is rarely reported. The production of spores from Streptomyces griseorubens JSD-1 was investigated in shaker-flask cultivation in this study. The optimal carbon, organic nitrogen and inorganic nitrogen sources were sucrose, yeast extract and urea, respectively. Plackett–Burman design (PBD) was adopted to determine the key medium components, and the concentration levels of three components (urea, NaCl, MgSO4·7H2O) were optimized with the steepest ascent path and central composite design (CCD), achieving 1.72 × 109 CFU/g of spore production. Under the optimal conditions (urea 2.718% w/v, NaCl 0.0697% w/v, MgSO4·7H2O 0.06956% w/v), the practical value of spore production was 1.69 × 109 CFU/g. The determination coefficient (R2) was 0.9498, which ensures an adequate credibility of the model.

EFFECTS OF NITROGEN SOURCES AND ORGANIC MATTER ON NITROGEN FIXATION AND YIELD OF SOYBEANS

1972 ◽  
Vol 52 (6) ◽  
pp. 991-996 ◽  
Author(s):  
H. S. JOHNSON ◽  
D. J. HUME
Keyword(s):  
Organic Matter ◽  
Nitrogen Fixation ◽  
Seed Yield ◽  
Inorganic Nitrogen ◽  
Nitrogen Sources ◽  
Cattle Manure ◽  
Control Treatment ◽  
Available N ◽  
Corn Cobs ◽  
Ground Corn

The effects of two sources of nitrogen and ground corn cobs, applied either alone or in combination, on nitrogen fixation and seed yield of Glycine max (L.) Merr. cult Altona were investigated in an area where control plants fixed only 7.5 kg N2/ha. Treatments were: N, 280 kg N/ha as NH4NO3; organic matter (O.M.), 14 T (dry wt)/ha of ground corn cobs as an organic matter source; N + O.M.; M1; 88 T/ha of liquid cattle manure; M1 + O.M.; M2, 176 T/ha of liquid cattle manure; M2 + O.M.; and C, control. Treatment effects on nitrogen fixation, measured as acetylene reduction rates, and seed yield were related to the levels of available N supplied to the plants. Nitrogen fixation was progressively increased by treatments M1, M2 + O.M., M1 + O.M., and O.M., with the latter two fixing seven times as much nitrogen as the control. Final seed yield, however, was increased by treatments supplying the highest levels of inorganic nitrogen to plants, with N and N + O.M. producing higher yields than the control plots.

Sign in / Sign up

Export Citation Format

Share Document