scholarly journals Changes in Nucleic Acids and Other Phosphorus-Containing Compounds of Developing Wheat Grain

1963 ◽  
Vol 16 (2) ◽  
pp. 332 ◽  
Author(s):  
AC Jennings ◽  
RK Morton

In both tho developing endosperm and testa-perica.rp thero was a relationship between the content of inorganic phosphorus, acid-soluble acid-labile phosphorus, and acid-soluble organic phosphorus ("phytic acid"), and the water content. The times of restriction of supply of water to the endosperm and to the testa-perion!'p fairly closely corresponded with the times of initiation of rapid synthei?-is of phytic acid and of a corresponding rapid decline in content of inorganic phosphorus and reactive phosphoryl groups.

1962 ◽  
Vol 40 (9) ◽  
pp. 1251-1256 ◽  
Author(s):  
K. J. Scott ◽  
R. M. Smillie ◽  
G. Krotkov

A comparative analytical study has been made of normal and tumor tissues of red beet roots. Per μg DNA, the two tissues had similar cell numbers, protein contents, and respiratory rates. On the other hand, the fresh and dry weights, acid-soluble phosphorus including nucleotides, acid-labile phosphorus, and inorganic phosphate were higher in the normal tissues. Tumor tissues contained more RNA. These results are discussed in relation to the cellular metabolism of the normal and tumor tissues and it is suggested that the main metabolic differences between these tissues lie in the utilization of respiratory energy, rather than in its production.


1963 ◽  
Vol 43 (1) ◽  
pp. 97-106 ◽  
Author(s):  
R. L. Halstead ◽  
J. M. Lapensee ◽  
K. C. Ivarson

In a laboratory experiment, liming resulted in an average decline of 3.6 per cent in the total organic phosphorus content of incubated surface samples of seven acid soils from eastern Canada. Increases of 2.6 and 5.1 per cent in 1N H2SO4- and 4N HCl-soluble inorganic phosphorus, respectively, and a decrease of 46.4 per cent in NaHCO3-soluble organic phosphorus (pH 8.5) provided further evidence of mineralization of organic phosphorus following liming. There was some evidence, however, that the differences in NaHCO3-soluble organic phosphorus following liming were due only in part to mineralization, since Ca(OH)2 added to a soil just prior to extraction with NaHCO3 had a repressive effect on the solubility of the organic phosphorus compounds.Some mineralization of organic phosphorus occurred when unlimed samples were incubated in the laboratory for 9 months.Marked increases in microbiological activity, as indicated by increased numbers of microorganisms, and increased CO2 and NO3-nitrogen production, were associated with lower values for extractable organic phosphorus following liming. Partial sterilization of samples with toluene lowered biological activity in the unlimed and limed samples. Toluene was found, however, to have a positive effect on release of phosphorus from organic form.


2021 ◽  
Author(s):  
Bereket Ayenew Alemu ◽  
Asmare Melese

Abstract Background: In acid soils, soluble inorganic phosphorus is fixed by aluminum and iron, so that phosphorous availability to plant would be inhibited. Thus, an incubation study was conducted to evaluate the effects of lime, vermicompost, and mineral P fertilizer on the distribution of P fractions and oxalate and dithionite extractable aluminum and iron. The treatments consisted of three rates of phosphorous (0, 74.51 and 149.01 kg P ha-1), three rates of vermicompost (0, 5 and 10 ton VC ha-1) and four rates of lime (0, 5.70, 9.20, and 11.50 ton CaCO3 ha-1). The experiment was laid out as a complete randomized design in a factorial arrangement. Results: Combined application of lime, vermicompost and mineral P significantly increased (p<0.05) labile phosphorus fractions and decreased potential sorption capacities of the soil. As the increased soil pH, reduced exchangeable acidity and oxalate extractable Fe and Al the integrated applications of these amendments fixed aluminum and iron instead of phosphorus, thus rendering phosphorus available by keeping the inorganic phosphorus in a bioavailable labile phosphorus pool compared to sole application of the amendments. Conclusions: Combined applications of lime, vermicompost and inorganic P to acidic soils of Goha-1 in Cheha district could convey enhanced amount of available P and ensures the maintenance of higher levels of labile P. It might also contribute towards meeting crop P requirements.


1981 ◽  
Vol 12 (4) ◽  
Author(s):  
YU. G. BOSYAKOV ◽  
A. P. LOGUNOV ◽  
L. P. KRASNOMOLOVA ◽  
O. V. AGASHKIN ◽  
B. M. BUTIN

Author(s):  
Jie Wan ◽  
Xuyin Yuan ◽  
Lei Han ◽  
Hongmeng Ye ◽  
Xiaofan Yang

In this study, the characteristics and distribution of the organic phosphorus (Po) fractions in the surface sediments of seven inflow rivers around Hongze Lake in China were analyzed with a soil Po fraction method, as used by Ivanoff. The relationships between the Po fractions and physiochemical features of sediments were also discussed. The results showed that, the sediments of the rivers had been moderately pollution with certain ecological risk effects except the Waste Yellow River. The relative contribution order of the Po fractions in the sediments was residual Po > HCl-Po > fulvic acid-Po > humic acid-Po > labile organic phosphorus (LOP). Moderately labile organic phosphorus (MLOP) was the main part of the Po forms in the whole sediments. The risk of phosphorus released from river sediments was the highest in the western region, followed by the southwestern region, and finally the northwestern region. There were significant correlations between Po forms and total phosphorus (TP), inorganic phosphorus (Pi), and Po. Non labile organic phosphorus (NLOP) had the strongest correlation with TP. The distribution of Po forms in each region was different due to the impact of human activities, industrial and agricultural production and the land types; the heaver polluted sediments with higher Po fractions. It is suggested that most of the sediments of the inflow rivers in the regions have certain ecological risk effects and P of them have an important contributions on the eutrophication of Hongze Lake. Po forms can provide a reliable theoretical basis for dealing with the change of water quality and should be paid more attention in the lake eutrophication investigation. There was reciprocal transformation between different Po forms, especially non-bioavailable fraction can change into bio-available ones. The results can provide a basis for the earth cycle of phosphorus and a new perspective of eutrophication control of shallow lakes.


Water ◽  
2018 ◽  
Vol 10 (12) ◽  
pp. 1858 ◽  
Author(s):  
Xiaolong Cheng ◽  
Yanan Huang ◽  
Xunchi Pu ◽  
Ruidong An ◽  
Wendian Huang ◽  
...  

The Yarlung Zangbo River basin ecosystem is fragile. The distribution and transportation of phosphorus is of great significance for aquatic environmental protection and ecological security. The sequential extraction method and molybdenum antimony anti-spectrophotometry were used to measure the concentrations of different forms of phosphorus in the surface sediments from 15 sampling sites along the middle reaches of the Yarlung Zangbo River and its tributaries. The results show that the total phosphorus concentration in the surface sediments is 194.0~540.7 mg/kg, which is mainly composed of inorganic phosphorus. The concentrations of various phosphorus forms ranked as calcium-bound phosphorus (355.6 ± 86.0 mg/kg) > soluble phosphorus (15.9 ± 10.0 mg/kg) > iron-bound phosphorus (12.4 ± 12.3 mg/kg) > organic phosphorus (9.6 ± 6.1 mg/kg) > occluded phosphorus (9.2 ± 3.8 mg/kg) > aluminum-bound phosphorus (5.4 ± 2.3 mg/kg). On the whole, phosphorus concentration is greater in wet season than dry season. Regarding the spatial distribution characteristics, there are great disparities in the different forms of phosphorus in the middle reaches of the Yarlung Zangbo River. Comprehensive analysis shows that phosphorus of this area is mainly self-generated, and concentration of bioavailable phosphorus is small, demonstrating there will not be a large release. We also drew a “specific triangle” of the different forms of phosphorus concentrations in the research area and defined the “α” angle to determine the nutrient status of the overlying water quickly and effectively. Finally, phosphorus flux of the mainstream was estimated. This research may provide information on the phosphorus of Plateau Rivers.


2019 ◽  
Vol 5 (8) ◽  
pp. eaaw4307 ◽  
Author(s):  
Andrew M. Turner ◽  
Matthew J. Abplanalp ◽  
Alexandre Bergantini ◽  
Robert Frigge ◽  
Cheng Zhu ◽  
...  

For decades, the source of phosphorus incorporated into Earth’s first organisms has remained a fundamental, unsolved puzzle. Although contemporary biomolecules incorporate P(+V) in their phosphate moieties, the limited bioavailability of phosphates led to the proposal that more soluble P(+III) compounds served as the initial source of phosphorus. Here, we report via laboratory simulation experiments that the three simplest alkylphosphonic acids, soluble organic phosphorus P(+III) compounds, can be efficiently generated in interstellar, phosphine-doped ices through interaction with galactic cosmic rays. This discovery opens a previously overlooked avenue into the formation of key molecules of astrobiological significance and untangles basic mechanisms of a facile synthesis of phosphorus-containing organics in extraterrestrial ices, which can be incorporated into comets and asteroids before their delivery and detection on Earth such as in the Murchison meteorite.


1938 ◽  
Vol 28 (2) ◽  
pp. 234-246 ◽  
Author(s):  
L. A. Dean

1. Extractions of soils with sodium hydroxide, followed by an acid, have been used in an attempt to fractionate the soil phosphorus.2. Colorimetric methods for the estimation of the organic and inorganic phosphorus in alkali soil extracts have been suggested.3. The amount of soil phosphorus soluble in sodium hydroxide is affected by the active soil calcium. It is suggested that sodium-saturated soils be used when studying the alkali-soluble phosphorus.4. The acid-soluble phosphorus remaining in soil after extraction with sodium hydroxide was determined. This fraction appears by analogy to be similar to the apatites.5. The largest fraction of the total soil phosphorus was not dissolved by the sodium hydroxide and acid extractions. This fraction was not increased by the long-continued use of phosphatic fertilizers at Rothamsted and Woburn.6. Relatively large amounts of organic phosphorus were found in soils and the amounts were closely related to the carbon contents.


1969 ◽  
Vol 49 (3) ◽  
pp. 365-373 ◽  
Author(s):  
M. Lévesque

Fulvic acid–metal–phosphate complexes prepared in the laboratory and corresponding complexes extracted (0.1 N NaOH and chelating resin) from a soil were characterized by means of electrophoresis, Sephadex gel filtration, and methods for differentiation of organic and inorganic phosphorus. The findings can be summarized as follows:(1) The prepared material in aqueous solution (after purification by dialysis) comprised three different entities: a fulvic acid–metal–phosphate complex, a fulvic acid–metal complex, and unbonded inorganic phosphate. These entities were reaction products obtained during the formation of fulvic acid–metal–phosphate complexes.(2) Upon hydrolysis in mild alkaline media, the metal–phosphate bonds of the fulvic acid–metal–phosphate complexes were broken; the fulvic acid–metal complexes, freed from the phosphate, remained intact.(3) While metal ions were necessary for bridging phosphorus and fulvic acid, phosphorus in turn may have bridged the fulvic acid–metal units.(4) Significant amounts of complexed inorganic phosphorus were found intermixed with organic phosphorus compounds in soil extracts; this suggested the existence of organic matter metal–phosphate complexes in soil.


1990 ◽  
Vol 36 (7) ◽  
pp. 475-483 ◽  
Author(s):  
Cecilia Eriksson ◽  
Carlos Pedrós-Alió

The influence of selenite on the growth of bacterioplankton present in samples of three lakes was analyzed; these samples were collected in sulfate-rich, oligotrophic Lake Banyoles, moderately eutrophic Lake Erken, and hypereutrophic Lake Vallentunasjön. Experiments were set up in a completely randomized factorial design to analyze the effect of selenite alone and, in the same experiment, the effect of selenite in the presence of phosphate. Cultures of bacterioplankton, free of algae and zooplankton, diluted with filtered natural water, were used in the bioassays. The addition of 100 μg P∙L−1 to samples from Lake Banyoles, collected during the winter, enhanced cell yield 2.7 times; the addition of 10 μg P∙L−1 to samples from Lake Erken, collected during the spring, doubled the yield. Strong effects of phosphate on growth rates were found in samples from lakes Banyoles and Vallentunasjön. When bacteria from Lake Banyoles were exposed to 100 μg P∙L−1, the specific growth rate was 0.08 h−1 (log units), compared with 0.03 h−1 in the control. In spring, Lake Vallentunasjôn contained water with a considerable amount of dissolved organic phosphorus (18 μg P∙L−1); the addition of 100 μg P∙L−1, in the form of phosphate, resulted in a shorter lag phase of at least 48 h and reduced the specific growth rate to about half that in the control. Selenite had a significant positive effect on cell yield in samples from lakes Banyoles (p = 0.0001) and Vallentunasjön (p = 0.020), whereas the effect on cell yield in samples from Lake Erken was slightly negative (p = 0.110). The addition of selenite alone (550 ng Se∙L−1) to samples from Lake Banyoles, collected during the summer, doubled the biovolume of bacterioplankton within 37 h. Among winter bacteria from Lake Banyoles, selenite, at concentrations of 55 and 550 ng Se∙L−1, increased the number of bacteria twofold and threefold, respectively, but only when the phosphate level was high (100 μg P∙L−1). A high inorganic phosphorus level of 100 μg P∙L−1 was also necessary to stimulate the effect of selenite on bacterial growth in samples from Lake Vallentunasjön; 550 ng Se∙L−1 enhanced cell yield 24%. The negative effect of selenite on samples from Lake Erken was most obvious when phosphate (10 or 100 μg P∙L−1) had been added simultaneously (p = 0.030 for selenium and phosphorus interaction). Cell yields were always greater at the highest temperature. With samples from Lake Vallentunasjön, selenite stimulated bacterial growth at 25 °C but had no effect at 10 °C. With samples from Lake Banyoles, the simultaneous addition of phosphate and selenite increased cell yield threefold at 15 °C and only twofold at 30 °C. Key words: phosphorus, sulfate, Lake Erken, Lake Vallentunasjön, Lake Banyoles.


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