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PubMed2026

PGPR inoculation and growth enhancement of crops cultivated in hydroponic systems.

Plant growth-promoting rhizobacteria (PGPR) are ubiquitous rhizosphere microorganisms that promote plant health through various mechanisms. Although the study of PGPR inoculants in soil has been done for ages, their application in hydroponic systems has received relatively limited attention. This review identifies PGPR inoculants that are commonly used in hydroponics, methods of application, and their effects on plant growth and nutrient use efficiency. Literature shows that PGPR inoculants improve plant performance in controlled hydroponic systems through the production of growth-stimulating substances, nitrogen fixation, and improved nutrient acquisition. However, the plant growth responses are highly variable depending on the composition of nutrient solutions, environmental factors, crop and microbe species, and the type of hydroponic system. The review identifies various challenges of PGPR inoculation in hydroponic systems and future research directions to address the current gaps. Generally, the productivity of hydroponic systems can be enhanced through advanced inoculation strategies and the development of suitable carrier materials to improve inoculant survival, viability, and functions. Emphasis should also be placed on designing system-specific microbial consortia and Synthetic communities that are tailored to the unique ecological conditions of hydroponic systems.

Hydroponics↗

PubMed2026

Response to Letter to the editor to comment on "Is arthroscopically-assisted reduction and internal fixation (ARIF) superior to percutaneous fixation in talar neck fractures? A proportional meta-analysis".

Explore the source record for details and available documents.

Letter↗

PubMed2026

K-wire versus screw fixation in Scarf-Akin osteotomy for hallux valgus: A retrospective cohort study.

BACKGROUND: Retention of metal implants after Scarf-Akin osteotomy (SAO) may cause irritation and psychological discomfort, often necessitating a hardware removal procedure. This study aimed to introduce K-wire fixation, allowing for outpatient removal, and to compare it with screw fixation. METHODS: This retrospective study included 64 patients with hallux valgus, comprising 32 in the K-wire fixation group and 32 in the screw fixation group. Clinical outcomes were assessed using the American Orthopaedic Foot and Ankle Society (AOFAS) score, visual analogue scale (VAS), and patient satisfaction. Radiographic parameters included hallux valgus angle(HVA), intermetatarsal angle(IMA), and distal metatarsal articular angle(DMAA). RESULTS: Both groups showed significant clinical and radiographic improvement (P < 0.01). No significant between-group differences were observed in the other clinical or radiographic outcomes (P > 0.05). Treatment costs were significantly lower in the K-wire group (P < 0.001). CONCLUSIONS: K-wire fixation provides clinical and radiographic outcomes comparable to screw fixation, while avoiding the need for an additional procedure to remove the implant. LEVEL OF EVIDENCE: Level III.

Humans↗

PubMed2026

Comparative efficacy of percutaneous vertebroplasty combined with minimally invasive pedicle screw fixation versus percutaneous vertebroplasty alone in the treatment of elderly osteoporotic vertebral compression fractures.

The study aimed to assess the comparative efficacy of percutaneous vertebroplasty (PVP) combined with minimally invasive pedicle screw fixation versus PVP alone in elderly patients with osteoporotic vertebral compression fractures (OVCF). Ninety-four elderly patients with OVCF were randomly classified into the control (47 patients) and combined (47 patients) groups. The control group received PVP, while the combined group received PVP combined with minimally invasive pedicle screw fixation. Perioperative indicators such as intraoperative blood lose, operative time, and hospitalization time were recorded. Pain was assessed using the VAS before and at baseline and 1, 3, and 7 days postoperatively. At 1 and 3 days postoperatively, Serum CRP levels, WBC, and neutrophil counts were measured postoperatively. Radiographic outcomes (vertebral height ratio and Cobb angle), ADL scores, JOA scores, and ODI were evaluated preoperatively and at 3 months post-operation. Postoperative complications were documented. Baseline characteristics were comparable. The combined group showed superior pain relief, vertebral height restoration, Cobb angle correction, functional recovery, and reduced inflammatory markers (CRP, WBC, neutrophils) postoperatively (all P < 0.05). Blood loss and hospital stay were shorter in the combined group, though operative time was longer (P < 0.05). Complication rates did not differ significantly (P > 0.05). PVP combined with minimally invasive pedicle screw fixation yields better outcomes in elderly OVCF patients by enhancing pain control, vertebral height, and functional recovery without increasing perioperative risk.

Humans↗

PubMed2025

Effects of aerosol aging on composition and light-absorbance of nitrogen-containing organic compounds: Evidences from ultra-high-resolution mass spectrometry analysis.

Nitrogen-containing organic compounds (NOCs) are key components of particulate matter (PM), but their compositional evolution and light-absorbing properties during atmospheric aging remain poorly understood. In this study, ultra-high-performance liquid chromatography coupled with Orbitrap mass spectrometry was used to semi-quantitatively analyze 59 PM1 samples collected in Shanghai. NOCs accounted for 31 % and 64 % of the detected species in negative (ESI-) and positive (ESI+) ionization modes, respectively. Atmospheric aging significantly reduced the molecular diversity of polar organics, with both the number and mass concentration percentages of CHON- compounds showing significant negative correlations with aging degree. Van Krevelen analysis demonstrated a decrease in the number of carboxylic-rich alicyclic molecules and their CHON- contributions during the aging process (from 37.7 % in fresh samples to 21.2 % in aged samples). CHN+ compounds, a major NOCs group in ESI+ mode, also decreased with aging. Correlation analyses involving the Bep/(Bep+Bap) ratio, relative humidity, and mass absorption efficiency at 365 nm revealed a decline in light absorption capacity with aging, suggesting aqueous-phase oxidation as a dominant aging mechanism. CHON- and CHN+ compounds were identified as the principal light-absorbing constituents in PM1. This work provides new insights into the aging-induced transformations of NOCs in urban PM1, and their changing role in light absorption, highlighting the need for further investigation of the aging mechanisms of NOCs.

Aerosols↗

PubMed2025

Coupling of spectroscopy and nitrogen-oxygen isotopes unveils the mechanisms of dissolved organic matter and nitrate pollution in lakes within the agro-pastoral transition zone.

Lakes in arid and semi-arid regions are subjected to severe ecological stress, such as organic pollution, eutrophication, and salinization, due to climate change and human activities. This study investigates Chagannur Lake, a typical arid-region lake that is representative and ecologically sensitive in Northern China's agro-pastoral ecotone, to uncover its pollution characteristics and mechanisms. We employed fluorescence spectroscopy and stable isotope analysis to trace dissolved organic matter (DOM) and nitrate sources. The DOM composition was dominated by microbial metabolic byproducts and protein-like substances, suggesting that microbial processes are key to organic matter transformation. Source apportionment revealed that pollutants primarily originated from livestock and poultry manure (37.6 %), agricultural fertilizers (35.6 %), and soil erosion (24.7 %), with agricultural fertilizers contributing most significantly in the Gogstai River (63.3 %). A structural equation model (SEM) coupling spectral and mass spectrometric data revealed that microbial transformation significantly impairs the lake's self-purification capacity, thereby promoting pollutant accumulation (path coefficient = 0.91,*p < 0.05). Moreover, microbial processes link endogenous and exogenous pollution, a mechanism effectively traced by isotopic and fluorescence indices (path coefficient = 0.55, ⁎⁎p < 0.01). These findings enhance the understanding of pollution sources and transformation mechanisms in arid-region lakes and offer foundational theoretical support for policymakers engaged in pollution control strategies.

Lakes↗

PubMed2026

Comparative safety and operative efficiency of surgical approaches for open reduction and internal fixation of mandibular condylar fractures: a systematic review and network meta-analysis.

BACKGROUND: The optimal surgical approach for mandibular condyle fractures remains controversial, particularly regarding the trade-off between facial nerve safety and surgical efficiency. METHODS: Our systematic review and frequentist NMA analyzed studies evaluating open reduction and internal fixation (ORIF) for mandibular condyle fractures. The primary safety outcome was transient or persistent (≥6 months) facial nerve weakness. The efficiency outcome was operative exposure time. Surgical approaches were categorized, and random-effects NMAs estimated odds ratios (ORs) and mean differences (MDs). Treatments were ranked using P-scores, and clustered rankings explored safety-efficiency relationships. RESULTS: Overall, 121 studies (n = 6659 patients) were included. For facial nerve safety, endoscope-assisted (EA), preauricular transmasseteric anteroparotid (PATMA), and high submandibular (HSMA) approaches ranked highest, while the retromandibular transparotid (RMTA) approach carried a higher risk. Analyses restricted to persistent weakness yielded consistent results. For exposure time, submandibular (SM), HSMA, and retromandibular transmasseteric anteroparotid (RMTMA) approaches were most efficient. Clustered ranking analysis identified HSMA and RMTMA as achieving the best overall balance between safety and efficiency. Subgroup analyses confirmed the overall hierarchy, though evidence for high-level and intracapsular fractures remains limited. CONCLUSIONS: HSMA and RMTMA offer an optimal compromise between safety and efficiency for extracapsular condylar fractures, while EA may minimize nerve injury risk where technical expertise allows. High-quality comparative trials - particularly for intracapsular fractures - are warranted.

Humans↗

PubMed2026

The incidence and descriptive factors of calcaneal malunion after surgical fixation of intra-articular calcaneal fractures using the sinus tarsi approach: A retrospective cohort study with binary logistic regression analysis.

BACKGROUND: This study evaluated the incidence of calcaneal malunion after minimally invasive sinus tarsi approach (MIS-STA) in displaced intra-articular calcaneal fractures (I-ACFs) and identified related descriptive factors of calcaneal malunion. METHODS: A retrospective review of 99 displaced I-ACFs treated with MIS-STA was conducted. Demographic data, pre-operative radiographs, and operative details were analyzed. Outcomes included numerical rating scale (NRS) pain scores at rest and during activities of daily living (ADL), Foot and Ankle Ability Measure (FAAM) for ADL and radiographic parameters. Logistic regression was used to identify descriptive factors associated with malunion. RESULTS: Malunion occurred in 33/99 cases (33.3%). The significant descriptive factors were the initial Böhler angle < 0.5 °, time to surgery > 12.5 days, and Sanders type ≥ III. Malunion patients had significantly worse NRS and FAAM scores (p ≤ 0.001). CONCLUSION: Calcaneal malunion after MIS-STA occurred in one-third of cases, with three descriptive factors identified and poorer outcomes observed. LEVEL OF EVIDENCE: III, Comparative retrospective study with binary logistic regression analysis.

Humans↗

PubMed2026

Genomic determinants underlying biogenic amine detoxification phenotypes in food-associated lactic acid bacteria: Mechanism, evolutionary origin, and relevance to fermented food safety.

Biogenic amines (BAs) are toxic metabolites that accumulate in fermented foods and pose significant food safety concerns. Although several lactic acid bacteria (LAB) have previously been reported to exhibit strain-specific BA-degrading phenotypes, the genetic determinants underlying these activities have remained largely uncharacterized. Here, we analyzed 8251 LAB genomes to validate BA-degrading phenotypes. We predicted five BA-associated genes, including two direct biogenic amine-degrading genes (BADGs), mco and patA, and three polyamine-modifying genes (PMGs), speG, paiA, and bltD. Among BADGs, mco was broadly distributed across LAB and strongly enriched across food-associated niches. patA, organized within a conserved potD-glnB-potABC-patA cassette, is a putative, functionally distinct BADG in LAB, revealing a nitrogen-responsive polyamine uptake-catabolism module. Phylogenomics, phylogenetic reconciliation, and synteny analysis established that all five genes entered the LAB through episodic horizontal gene transfer followed by lineage-specific fixation. GC compositional bias and mobile genetic element association further corroborated the horizontal origin of the two BADGs. Structural analysis confirmed the conservation of catalytic core residues of BADGs across LAB, indicating strong purifying selection. Phenotype-to-genotype correlation with experimentally reported LAB suggested mco as a reliable genomic predictor of degrading phenotype. Integration of degradation and biosynthetic profiles predicted multiple LAB species capable of both synthesizing and degrading BA, along with 1823 genomes with degradation potential but lacking detectable BA biosynthesis genes. This study provides the first large-scale genome framework linking BA-degrading phenotypes with their genetic determinants in LAB and offers a rational basis for selecting BA-detoxifying strains for fermented food applications.

Biogenic Amines↗

PubMed2026

Nitrogen sources and concentrations shape algal odor compounds: Key drivers of β-cyclocitral and β-ionone in water bodies of the lower Yangtze River.

Taste and odor (T&O) compounds derived from cyanobacterial blooms pose escalating threats to freshwater security worldwide, yet the drivers of specific T&O metabolites remain poorly constrained. Here, we investigated the dual effects of nitrogen (N) sources and concentrations on the production of β-cyclocitral and β-ionone, two algal-derived T&O compounds, through integrated field surveys (54 sites across lakes and rivers) in the eutrophic lower Yangtze River, China, and laboratory cultivation of typical cyanobacteria (Microcystis aeruginosa and Pseudanabaena cinerea). Our field data revealed that the concentrations of β-cyclocitral and β-ionone in lakes and rivers were not significantly different, but increased with the trophic level index. Redundancy analysis and Mantel analysis showed that Microcystis and Pseudanabaena were potentially dominant contributors to β-cyclocitral and β-ionone in the water column. Structural equation modeling and variation partitioning analysis showed that enhanced nitrate (NO3--N) significantly promoted the production of these compounds. Laboratory experiments demonstrated that inorganic N (NaNO₃) maximized total T&O yields by promoting algal biomass, whereas organic N (urea and glutamic acid) elevated the T&O production per unit biomass by 1.5- to 9.5-fold. Notably, Pseudanabaena exhibited a 2.3-fold higher β-ionone yield than Microcystis, with greater sensitivity to N concentrations. Our study highlights the critical role of nitrogen pollution, both source and concentration, in the production of T&O compounds by phytoplankton and provides reference data for managing T&O issues in rivers and shallow lakes.

Norisoprenoids↗

PubMed2026

Gubernacular discontinuity and abnormal distal fixation in cryptorchidism: Challenging the classical concept.

BACKGROUND: The gubernaculum is essential for testicular descent, but its detailed surgical anatomy remains poorly understood. We have previously identified an unrecognized anatomy of the round ligament in female patients with sliding inguinal hernias. OBJECTIVE: This study investigated whether comparable anatomical features exist in the gubernaculum of male cryptorchidism patients, as compared to those identified in female sliding hernias. MATERIALS AND METHODS: We retrospectively analyzed undescended testes located in the inguinal canal that underwent open inguinal orchidopexy between 2016 and 2025. Laparoscopically managed nonpalpable testes and those with suprascrotal testes were excluded. To ensure consistent anatomical evaluation, a standardized surgical protocol supervised by the senior author was applied to all cases. Findings were verified using operative reports and video recordings. After dissecting the processus vaginalis along the internal spermatic fascia (transversalis fascia), the pars infravaginalis gubernaculi were exposed. The relationship between the plica gubernaculi and pars infravaginalis gubernaculi, as well as the site of distal gubernacular fixation, was assessed. RESULTS: A total of 64 undescended testes of 56 patients were included. Video recordings were available for 45 of these 64 testes (70%). A patent processus vaginalis was observed in 60 out of 64 testes (94%), while it was obliterated in two ascending testes and unknown in two. In all 64 testes (100%), the pars infravaginalis gubernaculi was not continuous with the plica gubernaculi, with the transversalis fascia interposed between them. This configuration closely resembled that described previously for sliding inguinal hernias in women. Distal gubernacular fixation was located lateral to the scrotum in 49 testes (77%), at the upper scrotal border in 14 testes (22%), and absent in one testis (1.6%). DISCUSSION: Cryptorchidism is associated with a previously unrecognized discontinuity of the gubernaculi and common abnormal distal gubernacular fixation. These findings challenge the conventional views on gubernacular invagination and suggest that abnormal distal fixation may contribute to failed testicular descent. The study was limited by its single-center, retrospective design, small sample size, and lack of a control group. CONCLUSION: This study identified a previously unrecognized discontinuity of the gubernaculi in cryptorchidism. These findings deepen the understanding of the pathophysiology of testicular descent.

Humans↗

PubMed2026

Effectiveness of kinesiologic tape in the management of postoperative trismus, discomfort, and edema in mandibular fractures: a randomized controlled trial.

OBJECTIVE: This study compared kinesiologic taping (KT) with conventional elastic adhesive bandaging in managing postoperative morbidity following open reduction and internal fixation. STUDY DESIGN: In this prospective, randomized controlled trial conducted at KLE Dr Prabhakar Kore Hospital, 26 patients with unilateral mandibular fractures were allocated into two groups: Group 1 received an elastic adhesive bandage (n = 13) and Group 2 used KT (n = 13). Pain (Visual Analog Scale), facial swelling (standardized linear measurements), and maximum interincisal distance were recorded at baseline and on postoperative Days 2 and 5. Data were analyzed using repeated measures ANOVA and independent t tests (p < .05). RESULTS: The KT group showed significantly lower pain scores and reduced facial edema at Days 2 and 5 compared with controls (P < .05). Trismus improved in both groups without significant intergroup differences. No adverse effects were observed. CONCLUSIONS: KT is a safe and effective adjunct for reducing early postoperative pain and edema after mandibular fracture fixation.

Humans↗

PubMed2026

Oblique Lateral Interbody Fusion With Lateral Vertebral Screw Fixation Versus Transforaminal Lumbar Interbody Fusion for Severe Lumbar Stenosis: Results of a Multicenter Randomized Controlled Trial.

BACKGROUND AND OBJECTIVES: The benefits of oblique lateral interbody fusion (OLIF) vs transforaminal lumbar interbody fusion (TLIF) in severe lumbar stenosis (Schizas C/D) remain uncertain. This randomized trial compared clinical, radiographic, and safety outcomes of OLIF and TLIF. METHODS: From November 2018 to December 2021, a prospective, multicenter, randomized controlled trial enrolled 260 adults with single-level severe stenosis and instability. In total, 224 patients were randomized to OLIF or TLIF. Prespecified outcomes followed consolidated standards of reporting trials. Primary outcomes were visual analog scale back/leg pain and Oswestry Disability Index (ODI), with minimal clinically important difference thresholds of ODI ≥12-13 points or ≥30% improvement, and visual analog scale ≥1.5-2.0 points. Radiographic measures included disc height, lumbar and segmental lordosis, and canal cross-sectional area (CSA). Complications were recorded. Ethics approval was obtained from the institutional review board, the trial was registered with ISRCTN.com , and all patients provided written informed consent. RESULTS: In total, 224 patients were randomized, 5 were lost to follow-up (TLIF n = 2, OLIF n = 3). Baseline features were comparable. OLIF was associated with shorter operative time, less blood loss, earlier ambulation, and shorter hospital stay (all P < .05). Both groups achieved significant, clinically meaningful improvements. OLIF showed greater back pain reduction at 3-6 months and 2 years ( P < .05) and superior ODI improvement at 3 and 6 months ( P < .001), although long-term ODI scores were similar. Radiographically, OLIF provided greater restoration of disc height and segmental lordosis (all P < .001) and demonstrated progressive CSA increase (dynamic decompression), whereas TLIF achieved immediate, sustained CSA enlargement. Fusion rates were comparable at 1-2 years. Complication rates were low and similar (7.3% TLIF vs 5.5% OLIF), with most OLIF-specific events transient. CONCLUSION: Both OLIF and TLIF yield improvements in severe lumbar stenosis. OLIF offers perioperative advantages, earlier functional recovery, radiographic restoration, and dynamic canal remodeling, supporting its role as an equivalent alternative for lumbar spinal stenosis with some secondary advantages.

Humans↗

PubMed2025

Depth-dependent multi-kingdom microbial interactions and biogeochemical cycling genes in eutrophic shallow lake sediments.

Microorganisms are pivotal to lake ecosystem biogeochemical cycles, yet existing research often focuses on single microbial kingdoms or surface sediments, neglecting multi-kingdom interactions and depth-resolved dynamics. To address these gaps, we used metagenomic sequencing to characterize microbial communities and their functional associations across overlying water and 0-45 cm sediments in four shallow lakes of the middle Yangtze River basin, China. Despite increasing bacterial and fungal diversity with depth, the 0-9 cm surface sediments exhibited the strongest multi-kingdom network connectivity and the greatest microbial stability. Functional genes exhibited clear depth-dependent patterns: nitrogen cycling genes, including those involved in dissimilatory nitrate reduction to ammonium, were most enriched in the upper 0-9 cm of sediment; methane cycling genes were positively correlated with depth; phosphorus cycling genes and some sulfur cycling genes, such as assimilatory sulphate reduction, declined with depth. Sediment microbial assembly was dominated by deterministic processes, in which the vertical distribution of functional genes was primarily dictated by heavy metals and conventional environmental indicators. These findings highlight depth-specific multi-kingdom microbial interactions and their associations with biogeochemical cycling, advancing lacustrine microbial ecology understanding and providing references for lake conservation under environmental change.

Lakes↗

PubMed2026

Effects of 12 weeks of resistance and concurrent training with graded protein intakes on lipid profile, kidney and liver biomarkers in middle-aged to older women.

PURPOSE: To examine secondary lipid, kidney-related, and liver-enzyme responses to three protein intakes during resistance training (RT) alone or the same RT plus cycling (CT) in middle-aged to older women. METHODS: In this randomized 2×3 factorial trial, 108 women aged 40-77 years were assigned to RT or CT and 0.8, 1.6, or 2.2 g kg-1 d-1 protein for 12 weeks. This complete-case secondary analysis included 83 participants. Linear mixed-effects models tested Time × Training, Time × Protein, and Time × Training × Protein effects, with false-discovery-rate-adjusted omnibus tests and Holm-adjusted contrasts. RESULTS: Triglycerides, total cholesterol, LDL-C, and apolipoprotein B decreased and HDL-C increased in all conditions. Lipid changes differed by protein condition, and several were more favorable with CT; however, CT comprised RT plus additional cycling and greater exercise exposure. Urea, blood urea nitrogen, creatinine, the blood urea nitrogen-to-creatinine ratio, and cystatin C increased, whereas three eGFR estimates decreased. Responses differed mainly between 0.8 and the two higher protein conditions, with little evidence of differences between 1.6 and 2.2 g kg-1 d-1. ALT, AST, and GGT differed by protein condition; AST and GGT also showed training-dependent responses. CONCLUSIONS: The dietary and exercise interventions modified lipid and clinical-chemistry responses. Because energy and food composition were not fully matched and CT added cycling to RT, the findings do not isolate protein dose or exercise modality. Changes in eGFR estimates and liver enzymes do not establish organ injury or long-term safety.

Humans↗

PubMed2026

Three-dimensional source apportionment and quantitative characterization of horizontal and vertical transport fluxes of O3 and its precursors in the Beijing-Tianjin-Hebei region, China.

Persistent surface ozone (O3) pollution in the Beijing-Tianjin-Hebei (BTH) region is driven by coupled precursor emissions and multi-scale transport, yet its altitude-dependent transport and source contributions remain insufficiently quantified. Here we integrated the Weather Research and Forecasting and the Comprehensive Air Quality Model with Extensions with the Ozone Source Apportionment Technology and a quantitative transport-flux framework to characterize three-dimensional source apportionment and horizontal/vertical fluxes of O3, Volatile Organic Compounds‌ (VOCs), and Nitrogen Oxides (NOx) across dynamic meteorological scenarios. Simulations showed that VOCs and NOx were dominated by local emissions near the surface (73.61 %-82.18 %), whereas surface O3 was primarily controlled by regional transport, with local contributions of only 11.01 %-13.75 %. Notably, the transport dominance further strengthened with altitude, exceeding 93 % at 1.8 km. Industrial and transportation emissions together contributed more than 75 % of precursor emissions and account for approximately 80 % of O3 formation, while favorable/unfavorable meteorological years modulated long-range transport efficiency and the vertical distribution of contributions. Horizontal flux analysis highlighted three major pathways (Northwest-Southeast, Southeast-Northwest, and Southwest-Northeast), with Shijiazhuang serving as a critical pollutant "sink" across altitude layers. Vertical fluxes revealed an altitude transition near 600 m: net downward transport dominated below 600 m, whereas enhanced summer convection promoted upward transport above 600 m. These results support altitude-dependent, scenario-specific strategies for coordinated regional O3 mitigation in the BTH region.

Ozone↗

PubMed2026

XsiAMT1.1a was identified as a novel ammonium uptake functional gene and its overexpression combined with GA4 application significantly increased yield in Arabidopsis thaliana.

Nitrogen (N) is a key limiting factor for plant yield. Ammonium is one of the main N forms absorbed by plants. Overexpression of ammonium uptake functional genes, such as ammonium transporter (AMT), can increase yield. However, the AMTs reported to enhance yield significantly is still limited. No researches have focused on the effect of overexpressing AMT combined with hormone application on yield improvement. In this study, we first investigated the role of XsiAMT1.1a, a potential ammonium uptake functional gene in an ammonium preference plant Xanthium sibiricum, in ammonium uptake by the analysis of bioinformatics, gene expression and subcellular localization, and the determination of ammonium uptake rate in endogenous silencing and heterologous overexpression plants. Subsequently, the effect of XsiAMT1.1a overexpression combined with hormone application on yield increase was further investigated in model plant Arabidopsis thaliana. Our results showed that XsiAMT1.1a shared the same conserved domains with AtAMT1 subfamily members and localized on the plasma membrane. XsiAMT1.1a was induced by N deficiency and highly expressed during the reproductive period. XsiAMT1.1a endogenous silencing and heterologous overexpression significantly decreased and increased ammonium uptake rates in X. sibiricum and A. thaliana, respectively. Overexpression of XsiAMT1.1a significantly improved total N accumulation, biomass and yield in A. thaliana, while XsiAMT1.1a overexpression combined with GA4 application had a stronger promoting effect on the above indicators. Our research identified a novel ammonium uptake functional gene, XsiAMT1.1a, and provided a new yield-increasing strategy which was verified in A. thaliana.

Arabidopsis↗

PubMed2026

Phosphorus modulates starch granule development and metabolic partitioning in wheat grain: Insights from SGAP proteomics and nutrition and processing quality.

This study investigates how phosphorus (P) levels are associated with carbon-nitrogen metabolism in wheat grains. Optimal P application (105 kg P₂O₅ ha⁻¹) was associated with enhanced pericarp-endosperm coordination, increased carbon allocation to the endosperm, and early B‑type starch granule formation. Starch granule‑associated protein (SGAP) proteomics showed that optimal P upregulated cytoskeletal and starch‑synthesis proteins bound to starch granules in the endosperm, while reducing storage protein degradation‑related SGAPs in the pericarp. These metabolic adjustments were correlated with increased grain‑filling intensity and duration, and were associated with the highest theoretical grain weight (50.70 mg). Furthermore, optimal P was associated with enrichment of amino acid biosynthesis pathways and with higher levels of essential amino acids (e.g., lysine and threonine by 17.0--26.8%) and an improved essential amino acid profile without altering total protein content. In contrast, excessive P (210 kg P₂O₅ ha⁻¹) was associated with disrupted inter‑tissue coordination but did not simply impair grain filling; instead, HP corresponded to a unique developmental program: it was linked to an early burst of C‑type starch granules (0∼5 µm) at 7 DPA, yet by maturity achieved the highest proportion of large A‑type granules (56.8%) and the highest total starch content (63.5%), together with elevated endosperm phosphorus at 14 DPA and enrichment of spliceosome‑related pathways. HP also showed higher levels of several functional amino acids (glutamate, cysteine, histidine, proline) compared to P0. However, HP was associated with a higher gliadin/globulin ratio and did not improve grain yield. These findings suggest that phosphorus supply is associated with grain quality through tissue‑specific metabolic reprogramming, and that precision management-rather than maximized application-warrants consideration for optimizing both yield and processing quality.

Triticum↗