Natural Phosphate Research Articles

Pengaruh Bulai pada Perubahan Indeks Kadar Klorofil, Serapan Fosforus dan Boron pada Jagung Manis

Maize production and quality are affected by infection with plant pathogens. One of the maize's essential and main diseases is downy mildew caused by Peronosclerospora spp. Downy mildew is a limiting factor in increasing production and can reduce production by 80-100%. It is because the affected plant cannot produce cobs. Pathogens obtain nutrients from the host cell, which can kill the cell and damage the surrounding tissues, resulting in visible downy mildew symptoms. Boron (B) plays a role in forming phloem, increasing the fruit's number, weight, bunch weight, and diameter. The primary function of B at the molecular level is the cross-linking of pectin in the plant cell wall. Ramnogalacturonan II (RG II) is a pectic polysaccharide that contributes to the mechanical strength and properties of the primary wall cross-linked by borate diesters. Phosphorus (P) controls the downsides in the greenhouse and field conditions. This study aims to measure changes in chlorophyll index, P and B uptakes in downy mildew affected plants. The field experiment used a group randomized design with six natural phosphate (FA) application treatments and four groups of borax doses as replicates. The results showed that the downy mildew decreased the chlorophyll index of the leaves at different levels of attack. The results of P concentration according to the position of healthy plant leaves were significantly different due to P treatment. In contrast to concentration B, there is no real difference. P and B uptake results in downy mildew-infested plants showed a significant difference only in P uptake in leaves with 1 FA treatment. Keywords: boron, downy mildew, maize, phosphate

Synthesis of High-Purity Hydroxyapatite and Phosphoric Acid Derived from Moroccan Natural Phosphate Rocks by Minimizing Cation Content Using Dissolution-Precipitation Technique.

This study investigates, in the first part, the synthesis and purification of a poorly crystalline hydroxyapatite (HAp) using natural Moroccan phosphate (Boucraa region) as a raw material. Despite its successful preparation, the obtained HAp was contaminated by several metallic cations (mostly Cd, Pb, Sn, Ti, Mn, Mg, Fe, and Al) migrated from the natural rocks during the digestion process, inhibiting HAp application in several sectors. To minimize the existence of these elements, the dissolution-precipitation technique (DP) was investigated as a non-selective purification process. Following the initial DP cycle conducted on the precipitated HAp, the removal efficiency was approximately 60% for Al, Fe, Mg, Mn, and Ti and 90% for Cd and Pb. After three consecutive DP cycles, notable improvement in the removal efficiency was observed, reaching 66% for Fe, 69% for Mg, 73% for Mn, and 74% for Al, while Cd, Pb, and Ti were totally removed. In the second part of this study, the purified HAp was digested using sulfuric acid to produce high-quality phosphoric acid (PA) and gypsum (GP). The elemental analysis of the PA indicates a removal efficiency of approximately 89% for Fe and over 94% for all the examined cations. In addition, the generated GP was dominated by SO3 and CaO accompanied with minor impurities. Overall, this simple process proves to be practically useful, to reduce a broad spectrum of cationic impurities, and to be flexible to prepare valuable products such hydroxyapatite, phosphoric acid, and gypsum.

Potato Growth Promotion Using an Ecological Phosphate Fertiliser Composed of the Phosphate-Solubilising Bacterium Pseudomonas rhizophila S211 and Natural Rock Phosphate

Potato Growth Promotion Using an Ecological Phosphate Fertiliser Composed of the Phosphate-Solubilising Bacterium Pseudomonas rhizophila S211 and Natural Rock Phosphate

Dataset: Cowpea Cultivars with Residual Organomineral Fertilizers from Crop Corn Cultivation

Cowpea is a critical dietary staple, especially in tropical and subtropical regions, due to its high protein content, essential amino acids, and other nutrients. This study aimed to assess the impact of residual organomineral fertilizers from a preceding corn crop on cowpea cultivars in southern Maranhão, Brazil. Two cowpea cultivars, BRS Tucumaque and BRS Nova Era, were evaluated using a randomized block design with three replications. This study incorporated two organomineral fertilizers derived from cattle manure and natural phosphates a simple superphosphate at a dose of 50 kg ha-1, and a control without phosphorus fertilization. The key agronomic traits measured included the number of nodes, pod per plant, grains per pod, thousand-grain weight, and yield per hectare. This research underscores the potential of organomineral fertilizers to enhance cowpea yield while minimizing environmental impact, offering a viable alternative to conventional fertilization methods. These findings advocate broader adoption of organomineral fertilizers in cowpea cultivation, potentially increasing yield and reducing costs. The database derived from this research is composed of 48 samples. Four types of fertilization were considered: control, simple superphosphate and two organomineral fertilizers; two planting systems with and without U. ruziensis straw; and two cultivars.

Triazole-linked Nucleic Acids: Synthesis, Therapeutics and Synthetic Biology Applications.

This article covers the triazole-linked nucleic acids where the triazole linkage (TL) replaces the natural phosphate backbone. The replacement is done at either a few selected linkages or all the phosphate linkages. Two triazole linkages, the four-atom TL1 and the six-atom TL2, have been discussed in detail. These triazole-modified oligonucleotides have found a wide range of applications, from therapeutics to synthetic biology. For example, the triazole-linked oligonucleotides have been used in the antisense oligonucleotide (ASO), small interfering RNA (siRNA) and clustered regularly interspaced short palindromic repeats (CRISPR)-Cas9 technology as therapeutic agents. Due to the ease of the synthesis and a wide range of biocompatibility, the triazole linkage TL2 has been used to assemble a functional 300-mer DNA from alkyne- and azide-functionalized 100-mer oligonucleotides as well as an epigenetically modified variant of a 335 base-pair gene from ten short oligonucleotides. These outcomes highlight the potential of triazole-linked nucleic acids and open the doors for other TL designs and artificial backbones to fully exploit the vast potential of artificial nucleic acids in therapeutics, synthetic biology and biotechnology.

Fingolimod phosphoramidate prodrugs: Synthesis, photophysical characterisation and lipid bilayer interaction of fluorescent tagged Prodrug

FTY720 (Fingolimod, Gilenya, 1), a structural analog of sphingosine (2) was the first orally administered drug approved for the treatment of multiple sclerosis (MS). However, the phosphate derivative of Fingolimod, namely Fingolimod-1-phosphate (FTY720-1P, 3) is the biologically active molecule in MS as well as in various lysosomal storage diseases such as mucolipidosis IV and Nieman-Pick. In all cases, Fingolimod requires to be phosphorylated, resembling the natural sphingosine phosphate (4), to accomplish its therapeutic/biological effects. Here, we report the synthesis of a small library of prodrugs that could provide the efficient delivery of 3, the bioactive species. Moreover, to gain insight about the biological behaviour of these novel candidates within human body such as cell and brain blood barrier penetration we have prepared and spectroscopically characterised a fluorescent tagged version of one of the new prodrugs. The behavior of our prodrugs with respect to biological membranes was evaluated by studying the interaction between the fluorescent prodrug 18 and DOPC/DPPC liposome models.

Agronomic advantage of bacterial biological nitrogen fixation on wheat plant growth under contrasting nitrogen and phosphorus regimes.

Given their remarkable capacity to convert atmospheric nitrogen into plant-accessible ammonia, nitrogen-fixing microbial species hold promise as a sustainable alternative to chemical nitrogen fertilizers, particularly in economically significant crops like wheat. This study aimed to identify strains with optimal attributes for promoting wheat growth sustainably, with a primary emphasis on reducing reliance on chemical nitrogen fertilizers. We isolated free nitrogen-fixing strains from diverse rhizospheric soils across Morocco. Subsequently, we conducted a rigorous screening process to evaluate their plant growth-promoting traits, including nitrogen fixation, phosphate solubilization, phytohormone production and their ability to enhance wheat plant growth under controlled conditions. Two specific strains, Rhodotorula mucilaginosa NF 516 and Arthrobacter sp. NF 528, were selected for in-depth evaluation, with the focus on their ability to reduce the need for chemical nitrogen supply, particularly when used in conjunction with TSP fertilizer and natural rock phosphate. These two sources of phosphate were chosen to assess their agricultural effectiveness on wheat plants. Twenty-two nitrogen-fixing strains (nif-H+) were isolated from various Moroccan rhizospheric soils, representing Bacillus sp., Pseudomonas sp., Arthrobacter sp., Burkholderia sp. and a yeast-like microorganism. These strains were carefully selected based on their potential to promote plant growth. The findings revealed that the application of Rhodotorula mucilaginosa NF 516 and Arthrobacter sp. NF 528 individually or in combination, significantly improved wheat plant growth and enhanced nutrients (N and P) uptake under reduced nitrogen regimes. Notably, their effectiveness was evident in response to both natural rock phosphate and TSP, demonstrating their important role in wheat production under conditions of low nitrogen and complex phosphorus inputs. This research underscores the significant role of nitrogen-fixing microorganisms, particularly Rhodotorula mucilaginosa NF 516 and Arthrobacter sp. NF 528, in wheat production under conditions of low nitrogen and complex phosphorus inputs. It showcases their potential to reduce chemical nitrogen fertilization requirements by up to 50% without compromising wheat plant yields. Our study emphasizes the importance of bacterial biological nitrogen fixation in meeting the remaining nitrogen requirements beyond this reduction. This underscores the vital role of microbial contributions in providing essential nitrogen for optimal plant growth and highlights the significance of biological nitrogen fixation in sustainable agriculture practices.

Corrected and republished from: "Vibrio fischeri Possesses Xds and Dns Nucleases That Differentially Influence Phosphate Scavenging, Aggregation, Competence, and Symbiotic Colonization of Squid".

Cells of Vibrio fischeri colonize the light organ of Euprymna scolopes, providing the squid bioluminescence in exchange for nutrients and protection. The bacteria encounter DNA-rich mucus throughout their transition to a symbiotic lifestyle, leading us to hypothesize a role for nuclease activity in the colonization process. In support of this, we detected abundant extracellular nuclease activity in growing cells of V. fischeri. To discover the gene(s) responsible for this activity, we screened a V. fischeri transposon mutant library for nuclease-deficient strains. Interestingly, only one strain, whose transposon insertion mapped to nuclease gene VF_1451, showed a complete loss of nuclease activity in our screens. A database search revealed that VF_1451 is homologous to the nuclease-encoding gene xds in Vibrio cholerae. However, V. fischeri strains lacking xds eventually revealed slight nuclease activity on plates upon prolonged incubation. This led us to hypothesize that a second secreted nuclease, identified through a database search as VF_0437, a homolog of V. cholerae dns, might be responsible for the residual nuclease activity. Here, we show that Xds and/or Dns are involved in essential aspects of V. fischeri biology, including natural transformation, aggregation, and phosphate scavenging. Furthermore, strains lacking either nuclease were outcompeted by the wild type for squid colonization. Understanding the specific role of nuclease activity in the squid colonization process represents an intriguing area of future research.IMPORTANCEFrom soil and water to host-associated secretions such as mucus, environments that bacteria inhabit are awash in DNA. Extracellular DNA (eDNA) is a nutritious resource that microbes dedicate significant energy to exploit. Calcium binds eDNA to promote cell-cell aggregation and horizontal gene transfer. eDNA hydrolysis impacts the construction of and dispersal from biofilms. Strategies in which pathogens use nucleases to avoid phagocytosis or disseminate by degrading host secretions are well-documented; significantly less is known about nucleases in mutualistic associations. This study describes the role of nucleases in the mutualism between Vibrio fischeri and its squid host Euprymna scolopes. We find that nuclease activity is an important determinant of colonization in V. fischeri, broadening our understanding of how microbes establish and maintain beneficial associations.

Phosphate solubilizing Pseudomonas and Bacillus combined with rock phosphates promoting tomato growth and reducing bacterial canker disease.

Nowadays, sustainable agriculture approaches are based on the use of biofertilizers and biopesticides. Tomato (Solanum lycopersicum L.) rhizosphere could provide rhizobacteria with biofertilizing and biopesticide properties. In this study, bacteria from the rhizosphere of tomato were evaluated in vitro for plant growth promotion (PGP) properties. Five Pseudomonas isolates (PsT-04c, PsT-94s, PsT-116, PsT-124, and PsT-130) and one Bacillus isolate (BaT-68s), with the highest ability to solubilize tricalcium phosphate (TCP) were selected for further molecular identification and characterization. Isolates showed phosphate solubilization up to 195.42 μg mL-1. All isolates showed phosphate solubilization by organic acid production. The six isolates improved seed germination and showed effective root colonization when tomato seeds were coated with isolates at 106 cfu g-1 in axenic soil conditions. Furthermore, the selected isolates were tested for beneficial effects on tomato growth and nutrient status in greenhouse experiments with natural rock phosphate (RP). The results showed that inoculated tomato plants in the presence of RP have a higher shoot and root lengths and weights compared with the control. After 60 days, significant increases in plant Ca, Na, P, protein, and sugar contents were also observed in inoculated seedlings. In addition, inoculated tomato seedlings showed an increase in foliar chlorophyll a and b and total chlorophyll, while no significant changes were observed in chlorophyll fluorescence. In greenhouse, two Pseudomonas isolates, PsT-04c and PsT-130, showed ability to trigger induced systemic resistance in inoculated tomato seedlings when subsequently challenged by Clavibacter michiganensis subsp. michiganensis, the causal agent of tomato bacterial canker. High protection rate (75%) was concomitant to an increase in the resistance indicators: total soluble phenolic compounds, phenylalanine-ammonia lyase, and H2O2. The results strongly demonstrated the effectiveness of phosphate-solubilizing bacteria adapted to rhizosphere as biofertilizers for tomato crops and biopesticides by inducing systemic resistance to the causal agent of tomato bacterial canker disease.

Acid-Free Processing of Phosphorite Ore Fines into Composite Fertilizers Using the Mechanochemical Activation Method

The relevance of involving substandard raw materials for the production of composite phosphorus-containing fertilizer production is significant due to the problem of providing food products for the growing population of the Earth. The main raw materials for phosphorus and composite phosphorus-containing fertilizer production are natural phosphate ores—phosphorites. However, in the process of mining and crushing, ~55–60% phosphorite ore fines are formed—a fraction of less than 10 mm, which is unsuitable for traditional processing into composite phosphorus-containing fertilizers. This article presents the results of physicochemical studies of the substandard fine fraction of phosphorite ore and the results of the studies of the possibility of their direct processing into phosphorus and composition of phosphorus-containing fertilizers using methods of mechanical and mechanochemical activation in the “Activator 4” planetary mill. The findings of the studies performed confirm the rather high efficiency of phosphorite ore fines’ mechanical activation and phosphorite-containing mixtures’ mechanochemical activation, which make it possible to significantly increase the content of assimilable phosphorus pentoxide P2O5 in composite phosphorus-containing fertilizers. The proposed innovative technology has fundamental differences from existing technologies, since the mechanochemical activation of a mixture of phosphorite ore fines and functional components will allow for direct acid-free and waste-free processing into phosphorus and composite phosphorus-containing mineral fertilizers.

One‐pot synthesis of aluminum phosphate‐supported, chitosan‐linked expandable graphite as a novel flame retardant for textile

AbstractAlthough cotton is the most common polymer in daily life, its limited use is due to its propensity to catch fire. To solve this issue, we developed an innovative flame‐retardant aluminum phosphate‐supported, chitosan‐linked expandable graphite composite (CAlPEG). The CAlPEG was synthesized by the reaction of natural graphite, aluminum phosphate, and chitosan biopolymer in a one‐pot method. When CAlPEG was coated with cotton fabric and exposed to continuous flame, the fabric did not catch fire up to 760 s, whereas only expandable graphite (EG), aluminum phosphate (AIP), and CS, coated cotton fabric burned within 20 s. Flame‐retardant proficiency of CAlPEG‐coated cloth was confirmed by flame tests such as a limiting oxygen index (LOI) and vertical flammability test. The blank cotton has 17% LOI and is completely burnt out. On the other hand, the as‐prepared composite has a 43% LOI rating, which denotes a high level of flame retardancy. The VFT test result showed the formation of a 3 cm char, which confirms the flame‐retardant material possesses self‐extinguishing qualities. The article develops a new method for utilizing bioresources such as chitosan and offers fresh perspectives on the environmentally friendly synthesis of phosphorylated EG‐linked chitosan on the AlPO4 matrix.

Robust, thermally insulating, and high-temperature resistant phosphate-enhanced mullite fiber porous ceramic composites

Porous mullite ceramics with high porosity and low thermal conductivity are urgently required as high-temperature thermal insulators in harsh environments. How to improve the strength of Porous mullite ceramics dramatically under the premise of no sacrificing its thermal insulating properties has remained an extremely challenging. Inspired by the freezing rain phenomenon in nature, high-strength and high-temperature resistant phosphate coatings were applied to the surface of mullite fibers, which significantly improved the mechanical properties of porous mullite ceramics without significantly increasing their thermal conductivity. The Al(H2PO4)3 solution concentration significantly affected the mechanical and thermal properties of the composite material, where the mechanical performance improved with an increasing Al(H2PO4)3 solution concentration. The phosphate coating phase stabilized with an increasing calcination temperature. The mechanical properties of the ceramics were improved by the excellent interfacial bonding strength between the coating and mullite fiber, and the forms of phosphate in the porous ceramics. The optimum composite preparation process increased its compressive strength by approximately nine-fold to 4.1 MPa and resulted in a thermal conductivity of only approximately 0.09 W/(m·K), demonstrating that the composite exhibited a significantly higher comprehensive performance than other previously reported porous ceramics and aerogels. Such new composites with excellent mechanical and thermal insulation properties exhibit excellent potential for high-strength thermal insulation in the chemical, metallurgical, pharmaceutical, aerospace, and other fields.

Phytic acid promotes high glucose-mediated bone marrow mesenchymal stem cells osteogenesis via modulating circEIF4B that sponges miR-186-5p and complexes with IGF2BP3

Diabetes-related hyperglycemia inhibits bone marrow mesenchymal stem cell (BMSC) function, thereby disrupting osteoblast capacity and bone regeneration. Dietary supplementation with phytic acid (PA), a natural inositol phosphate, has shown promise in preventing osteoporosis and diabetes-related complications. Emerging evidence has suggested that circular (circ)RNAs implicate in the regulation of bone diseases, but their specific regulatory roles in BMSC osteogenesis in hyperglycemic environments remain elucidated. In this study, in virto experiments demonstrated that PA treatment effectively improved the osteogenic capability of high glucose-mediated BMSCs. Differentially expressed circRNAs in PA-induced BMSCs were identified using circRNA microarray analysis. Here, our findings highlight an upregulation of circEIF4B expression in BMSCs stimulated with PA under a high-glucose microenvironment. Further investigations demonstrated that circEIF4B overexpression promoted high glucose-mediated BMSC osteogenesis. In contrast, circEIF4B knockdown exerted the opposite effect. Mechanistically, circEIF4B sequestered microRNA miR-186-5p and triggered osteogenesis enhancement in BMSCs by targeting FOXO1 directly. Furthermore, circEIF4B inhibited the ubiquitin-mediated degradation of IGF2BP3, thereby stabilizing ITGA5 mRNA and promoting BMSC osteogenic differentiation. In vivo experiments, circEIF4B inhibition attenuated the effectiveness of PA treatment in diabetic rats with cranial defects. Collectively, our study identifies PA as a novel positive regulator of BMSC osteogenic differentiation through the circEIF4B/miR-186-5p/FOXO1 and circEIF4B/IGF2BP3/ITGA5 axes, which offers a new strategy for treating high glucose-mediatedBMSCosteogenic dysfunction and delayed bone regeneration in diabetes.

Enhancing Hygiene and Technical Properties of Ceramic Tiles through Moroccan Phosphate Additives

This study offers a simple solution to manufacture ceramic tiles with good technical and hygienic properties. This solution consists of integrating the phosphate product from Morocco in the industrial formulation of ceramic tiles, to produce materials in compliance with the criterion of the ISO standard. For phosphate products, three grades were studied: HG-high grade, MG-medium grade, and LG-low grade. The results show that for materials containing these additives, there is both an effect of the concentration and type of additive on technical and hygienic properties. The mechanical property is improved when the incorporated component was richer in P2O5. Only the use of HG-high grade and MG-medium grade as an additive at least 15% makes it possible to satisfy the mechanical requirement. The anti-biofilm effect of natural phosphate (PN) as an additive to manufacture ceramic tiles is confirmed, it may prevent bio adhesion and biofilm formation at almost 75% for the HG-high grade and MG-medium grade. This solution could interest professionals and all users who care about the state of hygiene of their ceramic materials sensible to the formation of biofilm, like orthopaedic implants, swimming pool tile…etc.

Selection and agricultural use of potential phosphate-solubilizing bacteria isolated from poultry slaughterhouse sludge in maize

In the farming, increasing demands for higher yields has put pressure on land resources which eventually increased demand for phosphate fertilizers (non-renewable resource), given that low availability of phosphorus in many soils is often compensated by the application high doses phosphate fertilizers. Complementary, studies have been made with a view to select phosphate-solubilizing bacteria. The purpose of his study was to: (i) isolate and characterization potential phosphate-solubilizing bacteria from sludge from the wastewater treatment plant of a poultry slaughterhouse; (ii) evaluate the ability of bacteria to solubilize phosphate rock and promoting plant growth. The bacteria were isolated in culture medium containing calcium phosphate. Morphological characterization consisted in cell shape, Gram staining and the characteristics of the colonies. To assess natural phosphate (NPh) solubilization, maize seeds were inoculated together with Araxá phosphate. The experiment consisted of 10 treatments: eight bacterial isolates + NPh, NPh and a control. The experiment was carried out in a greenhouse for 45 days, in a randomized block design, with six replications. The variables measured were the growth characteristics of the maize. Eight strains were isolated, all stained gram-positive, and 90% were rod-shaped and 10% coccoid-shaped. Inoculation with isolate LSOF-7 (Sphinghomonas sp.) combined with NPh induced increased maize dry matter by 20% compared to the treatment containing only NPh and by 67% compared to the control. It was concluded that sludge from wastewater treatment plants of poultry slaughterhouses contains bacterial strains with potential to phosphate-solubilizing and them also probably present promoting plant growth and promote maize plant growth.

Synthesis of Tin/Tin Oxide (Sn-SnO2) Microparticles Scattered on Natural Phosphate and Its Utilization in Capturing Amoxicillin Antibiotic in Real Water Samples

Microparticles of tin and tin oxide scattered on natural phosphate (Sn-SnO2)-NPh were thermally prepared and then used as a modifier of a graphite electrode for amoxicillin (AMX) detection using DPV. It was characterized by FTIR, SEM and XRD. The Sn formation was confirmed by the appearance of their corresponding peaks in the XRD pattern. In addition, the transformation of Sn into SnO2 and Ca(SnO4) and SnF4 as a function of temperature was observed. The charge transfers resistance (Rct) value of the (Sn-SnO2)-NPh-CPE is 71.07 Ω, indicating a higher electron transfer capacity compared to NPh-CPE (92.32 Ω) and CPE (108.5 Ω). Also, it has an area surface high. This result indicates, the synergetic interaction between these materials structures increased the electrochemical activity. The AMX oxidation at the (Sn-SnO2)-NPh-CPE is controlled by a diffusion process with the transfer of two electrons. The quantification provided a good linear relationship in the range of AMX concentration from 7.0 × 10−7 to 1.0 × 10−5 mol l−1 with a correlation coefficient of 0.982. The detection limit was calculated as 1.89 × 10−7 mol l−1. Satisfactory results were obtained from the detection of the AMX in different samples using the prepared electrode.

Carbonate-hosted U-deposit in the Tummalapalle Area, Andhra Pradesh, India: A Potential Source to Generate Critical Minerals of REs, V, Mo, Co, Ni, Cu, Ag and Phosphate as Value-added Byproducts

Abstract The unique, large-tonnage (amongst the Indian U-deposits; hitherto ~ 0.222 million tonnes, constituting 59% of the Indian U-resources) but very low-grade (~ 0.045% U3O8) sedimentary, impure carbonate (dolostone)-hosted U-deposit, established by the Atomic Minerals Directorate for Exploration and Research (AMD), occurs at Tummalapalle (TMP) and its contiguous areas over a ~ 160-km long belt in the Kadapa, Anantapur and Kurnool districts of Andhra Pradesh, India. Since 2012, the TMP U-deposit has been under commercial utilization by the Uranium Corporation of India Ltd. (UCIL) focussing for recovery of U with underground mining and nearby processing plant. Petro-/minera-graphic and geochemical characterisation of the U-ore shows major impurities of phosphate and silicate minerals, besides accessory ore minerals, mainly of U and sulphides. From this ore, it may be possible to generate some of the most sought-after critical minerals (CMs), namely the rare earths (REs), V, Mo, Co, Ni, Cu, Ag, and phosphate as value-added by-products from its U-phases, sulphides and collophane. For this, it is proposed to undertake an integrated, comprehensive R&D project on the ore for (i) extraction, processing, and marketing of the above CMs, which will lead to a low-cost and more profitable recovery of its low-grade U, (ii) providing a cheap, natural phosphate for agriculture, (iii) treating dreaded fluorosis by carbonate-powder, and (iv) reducing the mining-/processing-waste and tailings, all of which together address the environment, society, and governance (ESG) in the study area.

Efficient recovery of phosphate from urine using magnesite modified corn straw biochar and its potential application as fertilizer

Conventional phosphate fertilization is costly, carbon intensive, induces water pollution, and depletes natural phosphate ores, calling for alternative circular sources such as recycling phosphate from urine. However, actual phosphate adsorbents are moderately efficient and generate additional waste. Magnesite-modified biochar was synthesized by co-pyrolysis of corn straw and magnesite, which was used to adsorb phosphate in simulated urine. We compared the properties with other magnesium-based biochar materials and conducted pot experiments to assess feasibility of the saturated magnesite-modified biochar using as an alternative phosphate fertilizer. The results showed that the maximum adsorption capacity of magnesite-modified biochar for phosphate in urine was 176.16 mg/g, with the primary adsorption mechanisms involving electrostatic attraction and ligand exchange. Pot experiments showed that after 21 days, the germination rate and plant height of plants were 5.0–5.8 and 9.4–10.0 times respectively higher than those of plants in soil without biochar application. Overall, the prepared magnesite-modified biochar promises as an adsorbent with dual benefits in water treatment and phosphorus recovery. The saturated magnesite-modified biochar is proved as a good alternative phosphate fertilizer with carbon fixation, emission reduction and phosphorus cycling functions.

Efficiency of phosphate fertilizers containing growth promoters in plant fertilization

Optimizing water and nutrient absorption in plants can be achieved through a practical strategy: the combination of plant growth promoters (PGPs) with phosphate fertilizers. This synergistic approach holds promise for enhancing agricultural productivity and sustainability. The objectives of this work were to produce new phosphate fertilizers containing PGPs and to evaluate the efficiency in promoting the growth of the roots and shoots and increased phosphorus (P) uptake of plants. The fertilizers produced contained reactive natural phosphate rock from Morocco and PGPs indole-3-butyric acid, humic substances or Trichoderma afroharzianum, and a control fertilizer, without adding PGPs. The agronomic efficiency of this fertilizers were evaluated in two contrasting soils. The additional treatment with the monoammonium phosphate was included. The experimental unit consisted of rhyzobox containing 350 cm3 of soil, where a soybean plant was grown. Thirty days after sowing, the root length, average root diameter, root tips, and fine roots were measured using WinRHIZO software. The dry matter and P content of the roots and shoots were determined. PGPs have a great potential to increase the efficiency of P absorption by plants and the photosynthetic rate, and have a great potential to increase phosphorus use efficiency. The effects of PGPs were observed in the architecture of the root system, leaf area, and increased P content by plants. In sandy soil, the application of phosphate rock containing humic substances, Trichoderma afroharzianum, and indole-3-butyric increases the total phosphorus uptake by 26.5%, 16.3%, and 12.2%, respectively.

Efeito residual de fontes de fósforo na presença e ausência de composto orgânico na produção de beterraba e chicória em cultivo sucessivo de brócolis

ABSTRACT The utilization of organic fertilizer for a short cycle crop may allow planting, in sequence, another short cycle crop, without the need for new fertilizers, reducing the costs of a new fertilization. The objective of this study was to evaluate the residual effect of fertilization applied to broccoli with phosphorus sources in the presence and absence of organic compost, on beet and chicory production in subsequent cultivation. In broccoli cultivation, four sources of phosphorus (thermophosphate, natural phosphate, natural reactive phosphate, and triple superphosphate) (600 kg/ha of P2O5) were evaluated in the presence and absence of organic compost (Visafértil®, 55 t/ha) before planting. After the removal of the cultural remains of broccoli, beet and chicory, seedlings were transplanted in the same plots of the first crop treatments. For each species eight treatments were evaluated, in a 4 x 2 factorial scheme. The first factor were the four sources of phosphorus and the second one was the application or not of organic compost before broccoli (hybrid BRO 68) planting. Treatments with organic compost showed greater production of beet and chicory, compared to the absence of compost. Fertilization with organic compost associated to the phosphorus sources provides necessary residual effect to beet and chicory production. The best P source for beet was triple superphosphate, and for chicory, in the absence of organic compost, triple superphosphate was the best source. In the presence of organic compost, the best sources were triple superphosphate and natural phosphate.