The effect of phosphorus on the growth and chemical composition of some tropical pasture legumes. II. Nitrogen, calcium, magnesium, potassium, and sodium contents

1969 ◽  
Vol 20 (4) ◽  
pp. 675 ◽  
Author(s):  
CS Andrew ◽  
MF Robins

This paper describes the effect of phosphorus on nitrogen concentration and on the total and individual concentrations of the cations calcium, magnesium, potassium, and sodium in the plant tops of 10 tropical legumes and one temperate legume when grown on two soils of different type, a light-textured solodic soil and a gley soil. Species used were Phaseolus lathyroides, P. atropurpureus, Stylosanthes humilis, Centrosema pubescens, Glycine javanica, Lotononis bainesii, Medicago sativa, Desmodium uncinatum, D. intortum, Vigna luteola, and Leucaena leucocephala. The nitrogen concentrations in the plant tops were increased by phosphorus supply, and good correlations were established between the nitrogen and phosphorus concentrations in the plant tops. When sodium dihydrogen phosphate was used as the source of phosphate, the sodium concentration in V. luteola, M. sativa, and L. bainesii was increased. Other species were not affected. Increasing phosphate supply as monocalcium phosphate had little effect on plant calcium concentration, but brought about an increase of magnesium in P. lathyroides and P. atropurpureus. In the solodic soil particularly, increases in phosphate supply in most species caused reductions in the potassium concentration, partly compensated by increases in the magnesium and calcium concentrations. Concentrations of the cations in the plants reflected the soil exchangeable cation composition. Plant species differed in their cation status. P. atropurpureus and P. lathyroides were relatively high in magnesium, L. bainesii and D. intortum in potassium, V. luteola, L. bainesii, M. sativa, and P. lathyroides in sodium, and C. pubescens and S. humilis in calcium.


1970 ◽  
Vol 10 (45) ◽  
pp. 442 ◽  
Author(s):  
KG Rickert ◽  
LR Humphreys

Townsville stylo (Stylosanthes humilis) was grown at Brisbane from February to June 1967 at initial densities of 10, 50, 250, 1250, and 6250 plants per m2 in boxes of sand which received basal nutrients and applications of 0, 10, and 50 kg P per hectare as calcium dihydrogen phosphate. Plots were irrigated frequently. Wide differences in dry matter yield between plant densities and a positive density phosphorus yield interaction persisted throughout the experiment. Peak yield was 1050 g per m2 with leaf area index (LAI) of 6.8. Intraspecific plant competition was evident in high densities 35 days after emergence, extending to the lower densities by 58 days. Plant mortality at the highest density was independent of phosphorus treatment. Maximum growth rates were reached earlier at high than at low plant densities ; the subsequent decreases in growth rate were expressed through drifts in both LA1 and NAR and were associated with progressively more unfavourable environmental conditions for growth. Nitrogen and phosphorus concentration of both shoots and roots decreased with increasing density. Phosphorus application did not affect nitrogen concentration. Exploitation of native soil phosphorus and recovery of applied phosphorus was greatest in high density swards. The data illustrate the loss in potential production which may occur in sparse swards of Townsville stylo and the limitations to efficient phosphorus response inherent in low density swards.



1977 ◽  
Vol 88 (3) ◽  
pp. 753-758 ◽  
Author(s):  
A. S. Bedi ◽  
G. S. Sekhon

SUMMARYIn a glasshouse experiment, fertilizer potassium and magnesium were applied in various amounts to 20 soils differing in the proportion of exchangeable potassium to the sum of the three exchangeable cations, potassium, calcium and magnesium. Maize, cv. Ganga-5, was grown as the test crop.In soils where the exchangeable cation ratio (K/Σ (K + Mg + Ca), in equivalents) was less than 0·025, potassium fertilizer significantly increased the dry-matter yield of maize. In soils where this ratio was between 0·026 and 0·05, application of potassium fertilizer was beneficial only up to the intermediate amount of 11 mg K/kg soil. Beyond this amount of application, addition of magnesium was necessary to increase yields. In soils where this ratio exceeded 0·05, potassium fertilizer reduced yields.An optimum ratio of exchangeable calcium, magnesium and potassium appears more important than their absolute amount. Magnesium application to high-potassium soils improved the cation equivalent ratio within the plant and the dry-matter yield.



Polymers ◽  
2021 ◽  
Vol 13 (2) ◽  
pp. 290
Author(s):  
Chih-Yu Cheng ◽  
Chia-Huang Tsai ◽  
Pei-Jyun Liou ◽  
Chi-Hang Wang

For pilot-scale production of chito-oligosaccharides, it must be cost-effective to prepare designable recombinant chitosanase. Herein, an efficient method for preparing recombinant Bacillus chitosanase from Escherichia coli by elimination of undesirable substances as a precipitate is proposed. After an optimized culture with IPTG (Isopropyl β-d-1-thiogalactopyranoside) induction, the harvested cells were resuspended, disrupted by sonication, divided by selective precipitation, and stored using the same solution conditions. Several factors involved in these procedures, including ion types, ionic concentration, pH, and bacterial cell density, were examined. The optimal conditions were inferred to be pH = 4.5, 300 mM sodium dihydrogen phosphate, and cell density below 1011 cells/mL. Finally, recombinant chitosanase was purified to >70% homogeneity with an activity recovery and enzyme yield of 90% and 106 mg/L, respectively. When 10 L of 5% chitosan was hydrolyzed with 2500 units of chitosanase at ambient temperature for 72 h, hydrolyzed products having molar masses of 833 ± 222 g/mol with multiple degrees of polymerization (chito-dimer to tetramer) were obtained. This work provided an economical and eco-friendly preparation of recombinant chitosanase to scale up the hydrolysis of chitosan towards tailored oligosaccharides in the near future.



2014 ◽  
Vol 809-810 ◽  
pp. 477-484
Author(s):  
Zhao Qing Qi ◽  
Hong Tao Wang ◽  
Jun Liang Dang ◽  
Shi Hao Zhang ◽  
Jian Hua Ding

The capacity of 10%, 30%, and 50% ammonium dihydrogen phosphate were replaced with an equal amount of three phosphate (potassium dihydrogen phosphate, sodium dihydrogen phosphate, disodium hydrogen phosphate) respectively. Magnesium phosphate cement was made by phosphate of replaced, which strength, setting time, fluidity, hydration temperature, and the hydration products was researched. The results show that: MPC was made that replaced with the equal amount of three kind of phosphate, which has good mechanical properties. Setting time and fluidity change along with the replacment. Three kind of phosphate replace ammonium dihydrogen phosphate, which change the hydration process of MPC. When ammonium dihydrogen phosphate was replaced by an equal amount of disodium hydrogen phosphate, the temperature of hydration is only 69.4 °C. XRD showed that the diffraction peaks of composite’s magnesium phosphate cement increases.



2020 ◽  
Vol 35 (3) ◽  
pp. 342-352
Author(s):  
Minghui Qi ◽  
Lijie Huang ◽  
Xiaofeng Xu ◽  
Tan Yi ◽  
Hao Xu ◽  
...  

AbstractChlorine dioxide is classified by the World Health Organization as a fourth-generation A1, widely used, safe, and effective disinfectant. It is widely used in bleaching, water treatment, oil extraction, aquaculture, plants, fruits and vegetables, meat products, preservation of aquatic products, food sterilization and sterilization industries. The technology of chlorine dioxide produced by the combination reduction method is widely used in domestic papermaking related companies. In order to promote the application of chlorine dioxide, the effects of storage conditions on the stability of chlorine dioxide solution prepared by the combination reduction method and the experimental study of decomposition kinetics were studied. Experiments have shown that high temperature, high pH and high initial concentration accelerate the decomposition of chlorine dioxide solution, and the addition of sodium dihydrogen phosphate (NaH2PO4) and dimethyl sulfoxide (DMSO) can inhibit the decomposition of chlorine dioxide. The kinetic experiments showed that the decomposition rate of chlorine dioxide was secondary to ClO2 and was −0.406 for [{\mathrm{H}^{+}}]. The apparent activation energy of chlorine dioxide solution decomposition reaction was 26.7 kJ·mol−1, and the decomposition rate equation of chlorine dioxide was established.



2017 ◽  
Vol 7 ◽  
Author(s):  
Juana Nieto ◽  
Antonio García-Fuentes ◽  
Llenalia M. García ◽  
Emilia Fernández-Ondoño

The aim of this study was to establish the evolution curves of macro- and micro-nutrients in olive leaves and the periods of time in which they are statistically stable and can be considered suitable for a nutritional diagnosis. The study was carried out in two farms of the province of Jaén (Andalucia, Southern Spain), with olive trees of the Picual variety, under an irrigation regime and no nutritional deficiencies over the entire year. The evolution curves of each nutrient had great similarities when comparing between farms and between periods. Only in some periods the farm “Poco Humo” had higher concentrations, probably due to the most favorable edaphic characteristics of this farm. Nitrogen and phosphorus showed minimum concentrations when the leaves were young and when they were one year old, and maximum concentrations during the winter. Potassium and boron showed higher concentrations when the leaves were young, and the concentrations decreased throughout the first year of life. Concentrations of calcium, magnesium and manganese had the opposite behavior: these accumulated in leaf until reaching maximum values in winter and then remained stable, with some oscillations but without statistically significant differences. No changes were observed in the zinc concentrations in the sampled periods. Periods of at least two consecutive months without statistically significant differences were found during the winter period for all elements except nitrogen. Analytical stability was observed from the second fortnight of May till the first fortnight of August for all elements except phosphorus and boron.



1977 ◽  
Vol 4 (5) ◽  
pp. 799 ◽  
Author(s):  
I Sofield ◽  
IF Wardlaw ◽  
LT Evans ◽  
SY Zee

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.



2020 ◽  
pp. 1-14
Author(s):  
Dina El Sherbiny ◽  
Mary E. K. Wahba

Abstract A simple HPLC technique has been utilized for rapid and sensitive quantitative analysis of two mixtures of drugs that are used during pregnancy and lactation. Drugs of the first mixture are used to manage gastrointestinal tract illness that are common during early stages of pregnancy, while pharmaceutical agents of the second mixture are administered over the counter as galactagogues or to overcome postpartum depression. Mixture I includes famotidine (FMT), ranitidine (RNT), nizatidine (NZT), and pantoprazole (PNT), which were separated on a C18 column using a mobile phase composed of methanol: 0.02 M sodium dihydrogen phosphate (60:40, v/v) of pH 6.9, adopting UV detection at 240 nm at a flow rate of 1 mL/min. Mixture II on the other hand, consists of domperidone (DOM), metoclopramide (MET), and sulpiride (SUL). These drugs were eluted using the same column and flow rate as those in mixture I, using a mobile phase consisting of acetonitrile: 0.075 M sodium dihydrogen phosphate (30:70, v/v) of pH 6 adopting a detection wavelength 270 nm. Two optimization protocols were utilized to optimize the chromatographic separation conditions, namely one factor at a time (OFAT) and design of experiments (DOE) where face centered cube response surface experimental design was chosen for this investigation. Comparison of the results obtained from both protocols reveals the accordance between them. Full validation procedure under guidance of United States Pharmacopoeia (USP) was applied to the proposed methods which enabled their application to separate the drugs of both mixtures in spiked rat whole blood samples and in vivo analysis of rat heart blood.



2020 ◽  
pp. 102-138
Author(s):  
Dafne Crutchik Pedemonte ◽  
Nicola Frison ◽  
Carlota Tayà ◽  
Sergio Ponsa ◽  
Francesco Fatone

This chapter gives an overview on the main technologies for nutrient removal from industrial wastewater by focusing on principles and operational parameters of real applications. A plethora of technologies can achieve the nutrients removal from wastewater depending mainly on their concentration and forms; however, biological nitrification and denitrification and chemical precipitation are the most common processes used today to remove nitrogen and phosphorus, respectively. Stripping, adsorption and membrane based processes for nutrients recovery can be economically viable only when nitrogen concentration is higher than 1.5-2 gN/L. On the other hand, phosphorus recovery should always be pursued and struvite crystalization is the most common option that should be evaluated together with biological phosphorus accumulation in sludge or plants for the following post-processing and valorization.



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