Phosphorus Absorption Research Articles

Bacillus B2 promotes root growth and enhances phosphorus absorption in apple rootstocks by affecting MhMYB15.

Due to the chelation of phosphorus in the soil, it becomes unavailable for plant growth and development. The mechanisms by which phosphorus-solubilizing bacteria activate immobilized phosphorus to promote the growth and development of woody plants, as well as the intrinsic molecular mechanisms, are not clear. Through the analysis of microbial communities in the rhizosphere 16S V3-V4 and a homologous gene encoding microbial alkaline phosphomonoesterase (phoD) in phosphate-efficient (PE) and phosphate-inefficient apple rootstocks, it was found that PE significantly enriched beneficial rhizobacteria. The best phosphorus-solubilizing bacteria, Bacillus sp. strain 7DB1 (B2), was isolated, purified, and identified from the rhizosphere soil of PE rootstocks. Incubatingwith Bacillus B2 into the rhizosphere of apple rootstocks significantly increased the soluble phosphorus and flavonoid content in the rhizosphere soil. Simultaneously, this process stimulates the root development of the rootstocks and enhances plant phosphorus uptake. After root transcriptome sequencing, candidate transcription factor MhMYB15, responsive to Bacillus B2, was identified through heatmap and co-expression network analysis. Yeast one-hybrid, electrophoretic mobility shift assay, and LUC assay confirmed that MhMYB15 can directly bind to the promoter regions of downstream functional genes, including chalcone synthase MhCHS2 and phosphate transporter MhPHT1;15. Transgenic experiments with MhMYB15 revealed that RNAi-MhMYB15 silenced lines failed to induce an increase in flavonoid content and phosphorus levels in the roots under the treatment of Bacillus B2, and plant growth was slower than the control. In conclusion, MhMYB15 actively responds to Bacillus B2, regulating the accumulation of flavonoids and the uptake of phosphorus, thereby influencing plant growth and development.

Salinity affects microbial function genes related to nutrient cycling in arid regions.

Salinization damages soil system health and influences microbial communities structure and function. The response of microbial functions involved in the nutrient cycle to soil salinization is a valuable scientific question. However, our knowledge of the microbial metabolism functions in salinized soil and their response to salinity in arid desert environments is inadequate. Here, we applied metagenomics technology to investigate the response of microbial carbon (C), nitrogen (N), phosphorus (P), and sulfur (S) cycling and the key genes to salinity, and discuss the effects of edaphic variables on microbial functions. We found that carbon fixation dominated the carbon cycle. Nitrogen fixation, denitrification, assimilatory nitrate reduction (ANRA), and nitrogen degradation were commonly identified as the most abundant processes in the nitrogen cycle. Organic phosphorus dissolution and phosphorus absorption/transport were the most enriched P metabolic functions, while sulfur metabolism was dominated by assimilatory sulfate reduction (ASR), organic sulfur transformation, and linkages between inorganic and organic sulfur transformation. Increasing salinity inhibited carbon degradation, nitrogen fixation, nitrogen degradation, anammox, ANRA, phosphorus absorption and transport, and the majority of processes in sulfur metabolism. However, some of the metabolic pathway and key genes showed a positive response to salinization, such as carbon fixation (facA, pccA, korAB), denitrification (narG, nirK, norBC, nosZ), ANRA (nasA, nirA), and organic phosphorus dissolution processes (pstABCS, phnCD, ugpAB). High salinity reduced the network complexity in the soil communities. Even so, the saline microbial community presented highly cooperative interactions. The soil water content had significantly correlations with C metabolic genes. The SOC, N, and P contents were significantly correlated with C, N, P, and S network complexity and functional genes. AP, NH4+, and NO3- directly promote carbon fixation, denitrification, nitrogen degradation, organic P solubilization and mineralization, P uptake and transport, ASR, and organic sulfur transformation processes. Soil salinity in arid region inhibited multiple metabolic functions, but prompted the function of carbon fixation, denitrification, ANRA, and organic phosphorus dissolution. Soil salinity was the most important factor driving microbial functions, and nutrient availability also played important roles in regulating nutrient cycling.

Dietary Phosphorus Levels Influence Protein-Derived Uremic Toxin Production in Nephrectomized Male Rats.

Gut microbiota-derived uremic toxins (UT) accumulate in patients with chronic kidney disease (CKD). Dietary phosphorus and protein restriction are common in CKD treatment, but the relationship between dietary phosphorus, a key nutrient for the gut microbiota, and protein-derived UT is poorly studied. Thus, we explored the relationship between dietary phosphorus and serum UT in CKD rats. For this exploratory study, we used serum samples from a larger study on the effects of dietary phosphorus on intestinal phosphorus absorption in nephrectomized (Nx, n = 22) or sham-operated (sham, n = 18) male Sprague Dawley rats. Rats were randomized to diet treatment groups of low or high phosphorus (0.1% or 1.2% w/w, respectively) for 1 week, with serum trimethylamine oxide (TMAO), indoxyl sulfate (IS), and p-cresol sulfate (pCS) analyzed by LC-MS. Nx rats had significantly higher levels of serum TMAO, IS, and pCS compared to sham rats (all p < 0.0001). IS showed a significant interaction between diet and CKD status, where serum IS was higher with the high-phosphorus diet in both Nx and sham rats, but to a greater extent in the Nx rats. Serum TMAO (p = 0.24) and pCS (p = 0.34) were not affected by dietary phosphorus levels. High dietary phosphorus intake for 1 week results in higher serum IS in both Nx and sham rats. The results of this exploratory study indicate that reducing dietary phosphorus intake in CKD may have beneficial effects on UT accumulation.

Endoplasmic reticulum protein of 57 kDa sulfhydration promotes intestinal calcium absorption to attenuate primary osteoporosis

Endogenous hydrogen sulfide (H2S) plays an important role in bone metabolism. However, the exact role of H2S in intestinal calcium and phosphorus absorption and its potential in preventing and treating primary osteoporosis remains unknown. Therefore, this study aimed to investigate the potential of H2S in promoting intestinal calcium and phosphorus absorption and alleviating primary osteoporosis. We measured the apparent absorptivity of calcium, femoral bone density, expression and sulfhydration of the duodenal endoplasmic reticulum protein of 57 kDa (ERp57), duodenal cystathionine γ-lyase (CSE) expression, and serum H2S content in adult and old CSE-knockout and wild-type mice. We also assessed intracellular reactive oxygen species (ROS) and Ca2+ content in CSE-overexpressing or knockout intestinal epithelial cell (IEC)-6 cells. In senile mice, CSE knockout decreased endogenous H2S, ERp57 sulfhydration, and intestinal calcium absorption and worsened osteoporosis, which were partially reversed by GYY4137, an H2S donor. CSE overexpression in IEC-6 cells increased ERp57 sulfhydration, protein kinase A and C activity, and intracellular Ca2+, whereas CSE knockout exerted the opposite effects. Furthermore, hydrogen peroxide (H2O2) stimulation had similar effects as in CSE knockout, which were reversed by pretreatment with sodium hydrosulfide before H2O2 stimulation and restored by DL-dithiothreitol. These findings suggest that H2S attenuates primary osteoporosis by preventing ROS-induced ERp57 damage in intestinal epithelial cells by enhancing ERp57 activity and promoting intestinal calcium absorption, thereby aiding in developing therapeutic interventions to prevent osteoporosis.

Assessment of some physiological indices in children with rickets

Rickets is found in all the countries of the world, but mostly in the northern countries, where insufficient solar radiation persists. Children born in autumn and winter more frequently get sick with rickets or it appears in a more serious form. Its incidence among children in the Republic of Moldova is 56.5%. Rickets is a disease of the whole body, which manifests itself predominantly in the bone system, determined by a temporary mismatch between the calcium and phosphorus needs of the growing and developing body and the insufficiency of the systems that ensure their intake in children. As a result of the decrease in the absorption of calcium, phosphorus, magnesium, vegetative dysfunctions and motility disorders of the gastrointestinal tract are often estimated as a consequence of rickets. Failure to treat this pathology in childhood can have unfavorable repercussions on the growth and development processes, which can be maintained throughout the rest of life.

Deciphering the Impact of ZnO Nanoparticles and a Sunscreen Product Containing ZnO on Phosphorus Dynamics and Release in Chlorella pyrenoidosa in Aquatic Systems.

Zinc oxide nanoparticles (ZnO NPs) expedite the conversion of organic phosphorus (OP) into PO4-P (Pi), facilitating phosphorus (P) absorption by algae. Our study explored the mechanisms of converting OP (2-aminoethylphosphonic acid (AEP) and β-glycerol phosphate (β-GP)) into Pi in Chlorella pyrenoidosa under P deficiency with sunscreen and ZnO NPs. Cell density followed the order of K2HPO4 > β-GP+ZnO > β-GP > AEP+ZnO > AEP > P-free. ZnO NPs promoted the conversion of β-GP, containing C-O-P bonds (0.028-0.041 mg/L), into Pi more efficiently than AEP, which possesses C-P bonds (0.022-0.037 mg/L). Transcriptomics revealed Pi transport/metabolism (phoB (3.99-12.01 fold), phoR (2.20-5.50 fold), ppa (4.49-10.40 fold), and ppk (2.50-5.40 fold)) and phospholipid metabolism (SQD1 (1.85-2.79 fold), SQD2 (2.60-6.53 fold), MGD (2.13-3.21 fold), and DGD (4.08-7.56 fold)) were up-regulated compared to K2HPO4. 31P nuclear magnetic resonance spectroscopy identified intracellular P as polyphosphate, orthophosphate, and pyrophosphate. Synchrotron radiation-based X-ray near-edge structure spectroscopy indicated that K2HPO4 and Zn3(PO4)2 in β-GP+ZnO were increased by 8.09% and 7.28% compared to AEP+ZnO, suggesting superior P storage in β-GP+ZnO. Overall, ZnO NPs improved photoinduced electron-hole pair separation and charge separation efficiency and amplified the ·OH and ·O2- levels, promoting OP photoconversion into Pi and algae growth.

Genome-wide identification and characterization of SPXdomain-containing genes family in eggplant.

Phosphorus is one of the lowest elements absorbed and utilized by plants in the soil. SPX domain-containing genes family play an important role in plant response to phosphate deficiency signaling pathway, and related to seed development, disease resistance, absorption and transport of other nutrients. However, there are no reports on the mechanism of SPX domain-containing genes in response to phosphorus deficiency in eggplant. In this study, the whole genome identification and functional analysis of SPX domain-containing genes family in eggplant were carried out. Sixteen eggplant SPX domain-containing genes were identified and divided into four categories. Subcellular localization showed that these proteins were located in different cell compartments, including nucleus and membrane system. The expression patterns of these genes in different tissues as well as under phosphate deficiency with auxin were explored. The results showed that SmSPX1, SmSPX5 and SmSPX12 were highest expressed in roots. SmSPX1, SmSPX4, SmSPX5 and SmSPX14 were significantly induced by phosphate deficiency and may be the key candidate genes in response to phosphate starvation in eggplant. Among them, SmSPX1 and SmSPX5 can be induced by auxin under phosphate deficiency. In conclusion, our study preliminary identified the SPX domain genes in eggplant, and the relationship between SPX domain-containing genes and auxin was first analyzed in response to phosphate deficiency, which will provide theoretical basis for improving the absorption of phosphorus in eggplants through molecular breeding technology.

Control of phosphorus release from sediment by the combined use of Elodea nuttallii, hydrous ferric oxide, zeolite and calcite: Efficiency, mechanism and response of bacterial communities

The effectiveness of Elodea nuttallii combined with a mixture of hydrous ferric oxide, zeolite and calcite (HZC) to reduce the internal loading of phosphorus (P) from sediment and its mechanism were studied, and the effect of Elodea nuttallii combined with HZC on the composition and function of the microbial communities in the surface sediment was also investigated. The results showed that the combination utilization of Elodea nuttallii and HZC can decrease the risk of phosphorus liberation from sediment to the overlying water, and the controlling efficiency of Elodea nuttallii combined with HZC was higher than that of Elodea nuttallii or HZC alone. The passivation of labile P measured by diffusive gradient in thin film device and mobile P played a crucial role in the control of internal P loading from sediment by the combined Elodea nuttallii + HZC treatment. HZC capping had a promoting effect on the growth of Elodea nuttallii. This was beneficial to the absorption of phosphorus from sediment by Elodea nuttallii. The combined application of Elodea nuttallii and HZC not only had a certain negative effect on the diversity of bacteria in the surface sediment, but also changed the microbial compositions of the surface sediment at the levels of phylum and genus. However, the microbial communities in the surface sediment still can perform good ecological function. The above results suggest that the combined application of Elodea nuttallii and HZC has a high potential in the management of internal P loading from sediment.

Underwater light source changes microecosystem constructed by Vallisneria spinulosa Yan for water restoration: Efficiency of water purification, characteristics of growth, and rhizosphere

Submerged macrophytes are effective in ecological restoration of water bodies polluted by nitrogen and phosphorus, and its restoration capacity depends on underwater illumination condition. This study explored the influencing mechanism of illumination on Vallisneria spinulosa Yan (V. spinulosa Yan) for water restoration. Addition of underwater light source increased the total nitrogen, ammonia nitrogen, total phosphorus, and phosphate removal loads of the V. spinulosa Yan growth system by 61.5, 39.2, 8.5, and 5.0 mg m−2 d-1, respectively. Meanwhile, the growth of V. spinulosa Yan was obviously promoted, even with high water turbidity. Although the biological nitrogen removal processes were inhibited by adding underwater light source, the growth of V. spinulosa Yan can be significantly improved, thus enhancing the efficiency of water purification via the absorption of nitrogen and phosphorus by V. spinulosa Yan. This study provides a theoretical foundation and technical support for application of submerged macrophytes in ecological water restoration.

Mechanistic insight into phosphorus migration pathways from oolitic hematite using in-situ observations during roasting and reduction process

Oolitic hematite is a promising alternative resource, in facing the iron ore downgrading. As oolitic hematite is often rich in phosphorus, an efficient separation of iron and phosphorus is necessary, in terms of utilizing both elements. Therefore, a close insight into the transformation of phosphorus-bearing minerals in the unique oolitic structure during the reduction process is important. To capture the real-time transformation of the apatite ring in the oolitic structure, in-situ observations under roasting, and CO/carbon reducing conditions were adopted by high-temperature confocal laser scanning microscopy. The results indicated that the apatite ring was transformed by four stages during the roasting process from 25 °C to 1400 °C: stabilization, defluorination, partial melting, and complete melting, which was: Ca5(PO4)3F → Ca3(PO4)2 → Ca3(PO4)2 + P2O5 liquid → P2O5 liquid. Under the CO reduction, the partial reduction of the phosphate at 1400 °C generated a Fe-Plow alloy. While the carbon reduction promoted iron phase absorption of phosphorus, forming Fe-Phigh alloy at 1400 °C. In addition, interfacial phenomena between apatite and slag melt were observed, and the dissolution of apatite (Ca/P molar ratio) into the slag melt was affected by the Fe/(Al + Si) molar ratio of the slag. Finally, using inverse error function methods, the diffusion coefficients of P and Ca increased significantly from the roasting to CO reduction and then to carbon reduction. These findings can benefit to understand phosphorus migration mechanisms, improving effective dephosphorization strategies for high-phosphorus oolitic hematite.

Knowledge, Attitude, and Practice (KAP) towards Vitamin D Deficiency among Adult Population in Qassim, Saudi Arabia

Background Vitamin D deficiency is becoming a worrying problem in Saudi Arabia and worldwide. However, vitamin D, a fat-soluble vitamin, plays a vital role in bone health by enhancing calcium and phosphorus absorption and metabolism. Also, vitamin D deficiency is remarkably correlated with the development of neurodegenerative diseases, such as senile dementia, schizophrenia, and multiple sclerosis. Objective The objective of our study was to evaluate the vitamin D deficiency Knowledge, Attitude, and Practice (KAP) among the adult population in Qassim, Saudi Arabia. Methods A cross-sectional design study was conducted among the general population in the Qassim area from March 2022 to July 2022. Results About 99.1% of people had heard about vitamin D, and the majority were aware that sunlight is the primary source of this vitamin. Despite the fact that 72.9% of them exposed themselves to sunshine, only 46.4% of participants liked going outside in the sun. Only 13.7% of the participants believed that they receive adequate sun exposure. The majority of participants (93.1%) were aware of the significance of vitamin D for bone health, and 48.4% were aware that there is a link between vitamin D insufficiency and other disorders, such as diabetes, cardiovascular disease, and depression. Additionally, the majority of individuals (91.0%) stated sunlight to be the source of vitamin D. Conclusion The findings have revealed Saudis to have a basic understanding of vitamin D deficiency. However, they were not sufficiently informed on the consequences of vitamin D deficiency.

Phosphate recovery from urban sewage by the biofilm sequencing batch reactor process: Key factors in biofilm formation and related mechanisms

The biofilm sequencing batch reactor (BSBR) technique has been deployed in the laboratory to enrich phosphorus from simulated wastewater, but it is still not clear what its performance will be when real world sewage is used. In this work, the effluent from the multi-stage anoxic-oxic (AO) activated sludge process at a sewage plant was used as the feed water for a BSBR pilot system, which had three reactors operating at different levels of dissolved oxygen (DO). The phosphorus adsorption and release, the biofilm growth, and the extracellular polymeric substances (EPS) components and contents were examined. The microbial communities and the signaling molecules N-acyl-l-homoserine lactones (AHLs) were also analyzed. Gratifyingly, the BSBR process successfully processed the treated sewage, and the biofilm developed phosphorus accumulation capability within 40 days. After entering stable operation, the system concentrated phosphate from 2.59 ± 0.77 mg/L in the influent to as much as 81.64 mg/L in the recovery liquid. Sludge discharge had profound impacts on all aspects of BSBR, and it was carried out successfully when the phosphorus absorption capacity of the biofilm alone was comparable to that of the reactor containing the activated sludge. Shortly after the sludge discharge, the phosphate concentration of the recovery liquid surged from 50 to 140 mg/L, the biofilm thickness grew from 20.56 to 67.32 μm, and the diversity of the microbial population plunged. Sludge discharge stimulated Candidatus competibacter to produce a large amount of AHLs, which was key in culturing the biofilm. Among the AHLs, both C10-HSL and 3OC12-HSL were significantly positively correlated with EPS and the abundance of Candidatus competibacter. The current results demonstrated BSBR as a viable option to enrich phosphorus from real world sewage with low phosphorus content and fluctuating chemistry. The mechanistic explorations also provided theoretical guidance for cultivating phosphorus-accumulating biofilms.

Adsorption of phosphate over a novel magnesium-loaded sludge-based biochar.

The production of sludge-based biochar to recover phosphorus (P) from wastewater and reuse the recovered phosphorus as agricultural fertilizer is a preferred process. This article mainly studied the removal of phosphate (PO4-P) from aqueous solution by synthesizing sludge-based biochar (MgSBC-0.1) from anaerobic fermentation sludge treated with magnesium (Mg)-loading-modification, and compared it with unmodified sludge-based biochar (SBC). The physicochemical properties, adsorption efficiency, and adsorption mechanism of MgSBC-0.1 were studied. The results showed that the surface area of MgSBC-0.1 synthesized increased by 5.57 times. The material surface contained MgO, Mg(OH)2, and CaO nanoparticles. MgSBC-0.1 can effectively remove phosphate in the initial solution pH range of 3.00-7.00, with a fitted maximum phosphorus adsorption capacity of 379.52 mg·g-1. The adsorption conforms to the pseudo second-order kinetics model and Langmuir isotherm adsorption curve. The characterization of the adsorbed composite material revealed the contribution of phosphorus crystal deposition and electrostatic attraction to phosphorus absorption.

Difference in the Effect of Applying Bacillus to Control Tomato Verticillium Wilt in Black and Red Soil.

In practical applications, the effectiveness of biological control agents such as Bacillus is often unstable due to different soil environments. Herein, we aimed to explore the control effect and intrinsic mechanism of Bacillus in black soil and red soil in combination with tomato Verticillium wilt. Bacillus application effectively controlled the occurrence of Verticillium wilt in red soil, reducing the incidence by 19.83%, but played a limited role in black soil. Bacillus colonized red soil more efficiently. The Verticillium pathogen decreased by 71.13% and 76.09% after the application of Bacillus combinations in the rhizosphere and bulk of the red soil, respectively, while there was no significant difference in the black soil. Additionally, Bacillus application to red soil significantly promoted phosphorus absorption. Furthermore, it significantly altered the bacterial community in red soil and enriched genes related to pathogen antagonism and phosphorus activation, which jointly participated in soil nutrient activation and disease prevention, promoting tomato plant growth in red soil. This study revealed that the shaping of the bacterial community by native soil may be the key factor affecting the colonization and function of exogenous Bacillus.

The transcriptomic analysis revealed the molecular mechanism of Arbuscular Mycorrhizal Fungi (AMF) inoculation in watermelon

Arbuscular mycorrhizal fungi (AMFs) and plants have a symbiotic relationship that facilitates nutrient accumulation for plant development and productivity. However, the molecular mechanism through which AMF controls the growth and development of plants is still largely unknown. In this study, the physiological and transcriptional responses of watermelon seedlings with and without AMF inoculation were compared. AMF inoculation improved the assimilation and absorption of potassium, phosphorus, and nitrogen. When inoculated, watermelon development was considerably greater than that in the absence of inoculation. Several differentially expressed genes (DEGs) were identified after 64 days after AMF inoculation. Specifically, the metabolic and signal transduction pathways exhibited an abundance of key DEGs. Inoculated watermelons resulted in 2259 DEGs involved in photosynthesis, chlorophyll biosynthesis, hormone biosynthesis, and nutrient transporters. Based on these results, it appears that AMF may enhance seedling growth and nutrient accumulation by stimulating gene expression. Notably, inoculation affected auxin-responsive proteins, auxin response factors, auxin-induced proteins, auxin-mediated proteins, and auxin transporter-like proteins, all of which are components of the auxin signalling pathway. The physiological and molecular analyses in this study may shed light on the underlying mechanism by which AMF affects the growth and development of watermelon.

Correlation of 25-Hydroxyvitamin D Deficiency with Ferritin, Thyroid-Stimulating Hormone, and Other Biochemical Parameters of Women in Baghdad Province

Abstract Background: The importance of vitamin D in facilitating the absorption of calcium and phosphorus from the intestines and maintaining appropriate levels of these minerals in the blood for normal bone mineralization is well-established. Objectives: Beyond its role in bone health, vitamin D has been shown to exert a significant influence on various biochemical processes and may impact the development of certain diseases, including infections, obesity, heart disease, and certain cancers. This study aimed to investigate the differences in vitamin D levels among women from Baghdad province and its potential associations with ferritin and thyroid-stimulating hormone (TSH). Materials and Methods: This cross-sectional study involved 171 apparently healthy women, categorized into two age groups: the menstrual age group (group A, mean age 36.4 ± 9.2) and the menopausal age group (group B, mean age 57.7 ± 8.4). Vitamin D levels, serum ferritin levels, and hemoglobin levels were assessed to understand the interplay between these parameters. Results: The results revealed that both groups exhibited low levels of vitamin D (group A: 916.56 ± 8.33; group B: 16.86 ± 10.45), low serum ferritin (group A: 11.9 ± 10.66; group B: 28.2 ± 13.67), and low hemoglobin levels (group A: 10.97 ± 1.74; group B: 11.42 ± 1.68). Notably, the results observed no significant differences in all studied parameters between these groups, except for serum ferritin (P &lt; 0.05). Additionally, the finding demonstrated a significant positive association between vitamin D and serum ferritin levels in both groups (group A, r = +0.569, P &lt; 0.000; group B, r = +0.405, P &lt; 0.01). Also, there was a significant moderate positive correlation between vitamin D and hemoglobin levels (group A, r = +0.43, P &lt; 0.001; group B, r = +0.312, P &lt; 0.04). However, no significant correlation was found between vitamin D and TSH, urea, and creatinine levels. Conclusion: The implications of this study suggest that vitamin D deficiency may serve as a useful predictor and have an adverse effect on anemia in women.

Impacts of cobalt and zinc on improving peanuts nutrient uptake, yield and irrigation water use efficiency under different irrigation levels

The knowledge of proper fertigation across various irrigation levels is necessary for maximizing peanut yield and irrigation use efficiency in arid areas, and it also can effectively alleviate the risk of nutrient deficiency induced by water stress. This study evaluated the effectiveness of cobalt combined with two zinc application methods on peanut nutrient uptake, yield, and irrigation water use efficiency across varying irrigation levels. A split-split plot experiment was carried out in 2021 and 2022. Three peanut gross water requirement (GWR) levels (100%, 80%, and 60%) were designated for main plots. Subplots featured plants treated with either 0 or 7.5 mg L−1 of cobalt. The sub-sub plots assessed chelated zinc effects at rates of 0 and 2 g L−1 via foliar and soil applications. In comparison to the control (100% GWR), nutrient uptake decreased, with sodium being the exception, and there was an increase in soil pH at 60% GWR. The results showed also significant reductions in yield and water use by approximately 60.3% and 38.1%, respectively. At this irrigation level, applying zinc via soil, either alone or combined with cobalt, led to significant yield increases of 89.7% and 191.3% relative to the control. Also, it’s crucial to note that cobalt application negatively affected iron and copper at 60% GWR, but this impact was lessened with soil-applied zinc. Hence, under a similar circumstance, treating stressed peanut plants with additional foliar applications of iron + copper and applying zinc via soil, could enhance nutrient uptake and improve yield. On the other hand, at 80% GWR, a combination of foliar-applied zinc and cobalt, had a tremendous impact on the absorption of (nitrogen, phosphorus, magnesium, and zinc), resulting in enhanced agronomic traits and decreased water losses. Additionally, at this irrigation level, foliar zinc application alone yielded a 32.4% increase compared to the 80% GWR control. When combined with cobalt, there was a 70.0% surge in water use. Based on this knowledge, the study suggests using 80% GWR and treating peanut plants with a combination of foliar-applied zinc and cobalt. This strategy aids plants in countering the adverse effects of water stress, ultimately leading to enhanced yield and irrigation water use efficiency.

Analisis Serapan Hara N, P dan K Jaringan Cabai (Capsicum sp.) pada Variasi Tingkat Kemasaman Tanah

This research tested the effect of soil acidity level on the uptake of macro elements in plant tissue. This research is a type of experimental research that examines the effect of soil acidification levels on the absorption of N, P, and K nutrients in chili plant tissues. This research was conducted on the greenhouse experimental land of the Sambas State Polytechnic, Sambas Regency, West Kalimantan. This activity is carried out from March to October 2022. The research design used a descriptive analysize with three treatments, namely pH = 6 (P1), pH = 7 (P2), and pH = 8 (P3) which were repeated as many as 3 tests. Each treatment consisted of 30 plants planted in a planting medium mixed with soil, burnt husks and animal dung. N, P and K uptake is obtained through the analysis of the covering of stem and leaf tissues. The results showed that the difference in the level of acidification of the growing media did not have a effect on the level of absorption of nitrogen and phosphorus, but level of acidification have effect in potassium absorption in chili plants. Nitrogen content generally decreases in plant tissue samples aged 30 to 45 days after planting, while in plants aged 45 to 50 days after planting, there is enerally an increase in the accumulation of nitrogen in plant tissues. Absorption of phosphorus elements in tissues fluctuates over a period of 30 to 60 days after planting. The phosphorus content found in leaf tissue treatment pH 6 and pH 7 increased from the observation period of 30 to 60 days after planting. Absorption of potassium elements in tissues fluctuates over a period of 30 to 60 days after planting. An increase in Potassium content in stem and leaf tissues occurred in pH 6 treatment samples. Key words : chili, nitrogen, phosphor, potassium, uptake

The Use of Magnesium Fertilizer Can Improve the Nutrient Uptake, Yield, and Quality of Rice in Liaoning Province

In this study, the effects of the soil application and foliar spraying with magnesium fertilizers on rice yield and quality in Liaoning Province were investigated. Field experiments were conducted at Kaiyuan, Xinmin, and Dawa in 2022 and 2023. Magnesium fertilizers were used in the soil as magnesium sulfate monohydrate and silicon–magnesium fertilizer and on leaves was magnesium sulfate heptahydrate. The results showed that the application of 12 kg magnesium hm−2 in the soil at the Kaiyuan site can significantly increase rice yield by 14.8% compared with sites without magnesium fertilizer. The use of silicon–magnesium fertilizer showed a more obvious yield increase of 22.2%. The application of 3 kg magnesium hm−2 or 6 kg magnesium hm−2 on the leaf surface increased the rice yield at Kaiyuan by 19.4% and 21.6% and at Xinmin by 17.8% and 5.4%, respectively. The yield increase was more significant under the optimal fertilization treatment compared with the conventional fertilization treatment. The application of magnesium fertilizer increased the magnesium, nitrogen, and phosphorus contents in rice shoots and the potassium and crude protein contents in rice grains. The effect of foliar spraying with magnesium fertilizers was more obvious than soil application. Therefore, the magnesium fertilizer used on the leaf surface plays an important role in improving rice yield and quality in rice-growing areas with relatively rich soil magnesium content. Magnesium fertilizer can compensate for the yield decrease caused by the reduced use of nitrogen and phosphorus fertilizers by promoting nitrogen and phosphorus absorption in rice. Conclusively, the application of magnesium fertilizer is a promising measure to improve rice production in Liaoning province under a reduced nitrogen and phosphate fertilizer background.

Potential Role of Sugars in the Hyphosphere of Arbuscular Mycorrhizal Fungi to Enhance Organic Phosphorus Mobilization.

Arbuscular mycorrhizal (AM) fungi engage in symbiosis with more than 80% of terrestrial plants, enlarging root phosphorus (P) absorption volume by producing extensive extraradical hyphae (ERH) in the soil. In addition, AM fungi recruit and cooperate with soil bacteria to enhance soil organic P mobilization and improve fungal and plant fitness through hyphal exudates. However, the role of the dominant compounds in the hyphal exudates in enhancing organic P mobilization in the mycorrhizal pathway is still not well understood. In this study, we added sugars, i.e., glucose, fructose, and trehalose, which are detected in the hyphal exudates, to the hyphal compartments (HCs) that allowed the ERH of the AM fungus to grow or not. The results showed that in AM fungus-inoculated pots, adding three sugars at a concentration of 2 mmol C kg-1 soil significantly increased the phosphatase activity and facilitated the mobilization of organic P in the HCs. The addition of fructose at a concentration of 2 mmol C kg-1 soil was the most efficient in increasing the phosphatase activity and enhancing organic P mobilization. The released inorganic P was then absorbed by the ERH of the AM fungus. The enhanced mobilization of organic P was correlated with the increase in phoD gene number and the changing bacterial community in the presence of fungal hyphae. The sugar addition enriched the relative abundance of some bacterial taxa, e.g., Betaproteobacteriales. Our study suggested that the addition of the sugars by mycorrhizae could be a pivotal strategy in managing P uptake in agricultural production, potentially directing future practices to optimize plant-fungi-bacteria interactions for improved P use efficiency.