Search Results (2,638)

Hydroponic cultivation is expanding rapidly as a resource-efficient alternative to soil-based farming, but challenges related to nutrient management, abiotic or biotic stresses, and organic production still limit the system’s performance and efficiency. Biostimulants are increasingly being explored as a promising strategy to support productivity and sustainability in soilless systems. This review summarizes the current evidence on the use of plant biostimulants to support crop performance in hydroponic systems. Microbial biostimulants, such as plant growth promoting rhizobacteria, Arbuscular Mycorrhizal Fungi, and Trichoderma spp., have been reported to promote root growth by synthesizing phytohormones, enhance nutrient uptake, and reduce the impacts of salt and heat stress, with reported improvements in biomass and nutrient use efficiency. Seaweed extracts and protein hydrolysates modulate plant hormonal balance, improve antioxidant defense, and have been associated with improvements in yield and quality. Humic and fulvic acids increase micronutrient bioavailability through chelation and stimulate root activity through auxin-like effects. In organic hydroponics, biostimulants may help address the nutrient gap by accelerating organic matter mineralization. Existing key challenges include the lack of hydroponic-specific dosage guidelines and high commercialization costs. Future efforts should further evaluate system-specific strategies, including emerging tools such as artificial intelligence-optimized strategies and the use of clustered regularly interspaced short palindromic repeats-edited microbes to support the long-term sustainability of controlled environment agriculture. Full article

Phosphorus deficiency in the environment induces phosphate (Pi) starvation responses of plants, in which the phosphate transporter is one of the most critical functional genes in this response mechanism. As a prevalent green manure crop in China, Vicia villosa plays a critical role in sustainable agricultural systems, and the expression of its phosphate transporter gene (VvPHT1) is modulated by soil phosphorus availability, highlighting its key adaptive function in nutrient acquisition and utilization under low-Pi conditions. Functional studies of this gene and its promoter contribute to exploring the molecular mechanisms of the tolerance of green manure crops to low phosphorus stress and to improving phosphorus-efficient V. villosa varieties. In this study, analysis of the VvPHT1 promoter sequence revealed a 1524 bp region containing multiple root-specific cis-regulatory elements, including five NODCON2GM, one NODCON1GM, six OSE2ROOTNODULE, one OSE1ROOTNODULE, and fifteen ROOTMOTIFTAPOX1 motifs. Histochemical GUS staining of transgenic Arabidopsis (Arabidopsis thaliana (L.) Heynh.) showed that the VvPHT1 promoter directed root-specific expression of the GUS reporter gene. A fusion expression vector pCAMBIA1300-VvPHT1--GFP was constructed and transformed into tobacco (Nicotiana tabacum L.) cells for subcellular localization analysis, indicating that the protein encoded by VvPHT1 was localized to the plasma membrane. To quantify its expression, VvPHT1 transcript levels in VvPHT1-overexpressing Arabidopsis (OEPHT1) lines were analyzed by quantitative real-time PCR (qRT-PCR) under different phosphorus supply conditions. The results demonstrated that under low-Pi conditions, the expression of VvPHT1 was significantly upregulated in the OEPHT1 lines compared to those of normal-Pi conditions. Furthermore, under low-Pi treatment, the OEPHT1 lines showed significantly increased fresh weight, primary root length, phosphorus content, and chlorophyll content compared to the wild-type Arabidopsis (WT), while no such differences were observed under normal-Pi conditions. In conclusion, the VvPHT1 promoter exhibits root-specific activity, and the VvPHT1 gene encodes a plasma-membrane-localized phosphate transporter that is strongly induced by phosphorus deficiency. Its overexpression enhances phosphorus uptake and plant growth under low-Pi conditions, suggesting that VvPHT1 likely functions as a high-affinity phosphate transporter involved in the adaptation to phosphorus starvation. Full article

Wheat productivity and grain quality are strongly influenced by nutrient management and soil moisture availability. Nitrogen (N) and potassium (K) regulate biomass production, physiological stability and grain protein development. However, their efficiency varies under water-limited conditions. This study aimed to evaluate how soil moisture modulates nitrogen–potassium efficiency, nutrient partitioning, physiological responses and grain quality development in wheat. The current experiment was planned to assess the impact of varying but combined levels of N and K fertilizers on wheat crop growth and yield components as well as nutrient uptake and grain quality under different irrigation levels (i.e., normal irrigation Field Capacity (FC) 100%, partial water deficit FC75%, moderate water deficit FC50%, severe water deficit FC25%). The results of the study showed that increasing N-K supply enhanced biomass, chlorophyll contents, nutrient accumulation and grain quality under full irrigation, with N2K2 showing the highest growth, yield and quality traits. Under moderate deficit, N2K1 maintained a relatively stable yield and physiological performance, whereas severe moisture limitation markedly reduced nutrient uptake, grain development and fertilizer efficiency despite a higher NK application. Progressive reductions in irrigation also altered nutrient distribution among leaves, straw and grain, indicating moisture-regulated remobilization during grain filling. Maximum increments in values for plant height (27%), total biomass (108%), grain yield (183%), grain NPK content (38%, 6.3%, 26%), grain protein (38%) and wet gluten (38%) were noted in the N2K2 treatment at FC100%, but these parameters showed up to 80% reduction under the same treatment of N-K at FC25%. It is concluded that wheat response to N–K fertilization was moisture dependent and fertilizer rate alone did not ensure productivity under severe water deficit. Therefore, integrating nutrient supply with irrigation management is essential to sustain productivity and grain quality. Full article

Astragalus membranaceus is an important perennial medicinal plant whose roots constitute its primary medicinal organ; however, its cultivation is severely constrained by root rot caused by Fusarium oxysporum. This study aimed to characterize differences in the rhizosphere microbiome between healthy and diseased plants, identify antagonistic microorganisms from healthy rhizosphere soils, and investigate their suppressive effects on F. oxysporum and the associated host metabolic responses. High-throughput sequencing was used to compare bacterial and fungal communities in the rhizospheres of healthy and diseased plants. Microorganisms were isolated from healthy rhizosphere soils and screened for antagonistic activity against F. oxysporum, followed by validation in pot experiments. Metabolomic analysis was further conducted to assess host metabolic responses to microbial treatment. Root rot disease significantly altered the dominant composition of rhizosphere microbial communities and was associated with reduced fungal diversity and lower bacterial richness in diseased soils. Co-occurrence network analysis revealed increased complexity in bacterial networks and strengthened positive correlations among fungal taxa under diseased conditions. A total of 81 microbial strains were isolated from healthy rhizosphere soils, among which Penicillium halotolerans exhibited the strongest inhibitory activity against the mycelial growth of F. oxysporum. Pot experiments further supported its suppressive effect on Astragalus root rot. Metabolomic analysis indicated that P. halotolerans treatment was associated with changes in host metabolic profiles related to energy metabolism, defense-associated protein synthesis, and nutrient uptake. Overall, this study identified P. halotolerans as a fungal strain with antagonistic activity against F. oxysporum and provided initial evidence for its association with the suppression of Astragalus root rot. These findings offer candidate microbial resources and mechanistic insights for understanding rhizosphere-associated disease suppression in Astragalus membranaceus. Full article

Ratoon rice is a unique cropping system that utilizes the regenerative capacity of rice tillers to achieve one sowing with two harvests in a single growing season, thus exhibiting great yield potential. However, the ratooning ability is often constrained by impaired root function after the first harvest. In this study, we established an integrated nutrient management (INM) strategy to enhance root growth and function, thereby improving nutrient use efficiency and yield. Compared with farmers’ conventional management (FCM), INM increased annual total yield by 7.8% and 13.9% and enhanced ratooning ability by 20.7% and 19.0% in 2024 and 2025, respectively. INM consistently maintained higher root biomass in both main and ratoon crops: by 26.9% and 54.0% in 2024, and by 44.8% and 26.0% in 2025. Root biomass was significantly and positively correlated with brown rice weight across both seasons, and was positively associated with ratooning ability. INM also promoted early root establishment after transplanting, increasing the white-root number by 105.7%, 175.0%, and 484.8% at 3, 5, and 14 days after transplanting (DAT), respectively. Meanwhile, the xylem sap exudation rate and root triphenyl tetrazolium chloride (TTC) reduction activity were increased by 37.4% and 64.5% relative to FCM. In the 2024 ratoon season, INM improved nutrient use efficiency, with partial factor productivity (PFP) of nitrogen (PFP_N), phosphorus (PFP_P), and potassium (PFP_K) increased by 371.0%, 59.3%, and 91.1%, respectively. Gene Set Enrichment Analysis (GSEA) revealed significant enrichment of gene sets involved in root growth, development, nutrient acquisition, and assimilation under INM, providing molecular evidence for root-mediated nutrient synergy. In summary, INM enhances root growth and function, promotes nutrient uptake and utilization, and consequently improves yield. These results offer a practical management strategy supported by physiological and transcriptomic evidence for boosting ratoon rice production via root-mediated nutrient synergies. Full article

Phosphorus (P) availability is currently a limiting factor for agricultural production, especially in tropical soils, and its interaction with cationic micronutrients can significantly affect physiological efficiency and nutrient uptake by plants. Therefore, this study aimed to evaluate the uptake kinetic parameters described by the Michaelis–Menten model (Vmax, Km, and Cmin) for P as a function of the supply of Cu, Fe, Mn, and Zn, as well as the kinetic parameters of Cu, Fe, Mn, and Zn as a function of P supply in cotton (Gossypium hirsutum L.). The experiment was conducted in a greenhouse at the experimental unit of CENA, in Piracicaba, São Paulo, Brazil, using individual pots. Phosphorus concentration and accumulation were reduced only under Fe and Zn deficiency, with reductions of up to 60% in the shoots and 85% in the roots. Zn deficiency caused a drastic reduction in P uptake capacity, with Vmax decreasing from 590 to 50.85 µmol g⁻¹ h⁻¹ (approximately a 12-fold reduction), accompanied by an increase in Cmin (from 269 to 1508 µmol L⁻¹). In terms of micronutrient kinetics, P omission reduced plant growth and affected only Fe and Zn uptake. For Fe, Km increased from 12.82 to 27.31 µmol L⁻¹ and Cmin from 1.03 to 20.51 µmol L⁻¹. For Zn, and Vmax decreased from 0.16 to 0.02 µmol g⁻¹ h⁻¹ (approximately 8-fold), while Cmin increased from 0.08 to 1.56 µmol L⁻¹. These results demonstrate a strong interaction between P, Fe, and Zn, highlighting their regulatory roles in nutrient uptake and providing mechanistic insights into plant nutritional efficiency. Full article

Background: Malaria parasites import essential nutrients from plasma into their host erythrocytes through the plasmodial surface anion channel (PSAC), a conserved ion and nutrient channel on the infected cell surface. A parasite-encoded ternary complex consisting of CLAG3, RhopH2, and RhopH3 determines PSAC activity, but the precise contributions of each member to formation of the nutrient uptake pore remains uncertain. Methods: Here, we devised a two-step CRIPSR transfection strategy to examine an amphipathic CLAG3 helix, termed α-helix 44 (α-H44), as a candidate pore-lining domain. Results: A CLAG3 truncation protein without α-H44 phenocopies a CLAG3 knockout line, suggesting a critical role of α-H44 in formation of the nutrient channel; CLAG3 restoration using a recodonized α-H44 restores PSAC activity fully. A saturation mutagenesis library that splits the helix into four sequential segments was devised and implemented. Two engineered mutants exhibit distinct PSAC phenotypes; their cultures failed to expand in a modified medium that approximates in vivo nutrient availability. Conclusions: These studies support a α-H44 role in channel permeation and block by a strain-specific inhibitor. Our strategy will enable saturation mutagenesis to determine how PSAC achieves its unique ion and nutrient selectivity and should help guide drug discovery against this antimalarial target. Full article

Tree and shrub planting is a widely used strategy to restore degraded semi-arid grasslands. Although nutrient resorption is a key adaptation to nutrient-limited environments, its dynamics at decadal scales remain poorly understood. In this study, we measured species-averaged nitrogen resorption efficiency (NRE) at both community and functional group levels, together with soil nutrients, across 20- and 40-year shrub-planted sites and a 40-year tree-planted site in Inner Mongolia, China. At the community level, green and senesced leaf nitrogen (N) concentrations, NRE, and aboveground biomass did not differ significantly among sites. However, clear differences emerged at the functional group level: Poaceae exhibited higher NRE than forbs and lower senesced leaf N than both forbs and Fabaceae. As restoration progressed, Poaceae replaced forbs as the dominant group, coinciding with increased soil nutrient availability. Notably, NRE in Poaceae declined with increasing soil nutrients, suggesting a shift toward greater reliance on direct soil nutrient uptake. This shift, combined with the production of low-nitrogen litter by dominant Poaceae species, may ultimately slow soil nutrient accumulation. Our findings highlight the importance of functional group dynamics in regulating long-term nutrient resorption and cycling and suggest that managing Poaceae dominance could enhance long-term soil nutrient enrichment and biodiversity in restored semi-arid grasslands. Full article

Lime and gypsum are widely used to correct soil acidity and improve grain yields in Brazilian agricultural systems. However, limited information is available on their effectiveness and application practices in degraded sandy soils typical of older agricultural frontiers, such as those in Rio de Janeiro State. This study evaluated the effects of surface application versus the incorporation of lime and gypsum into the soil through tillage operations on soil chemical properties, nodulation, and grain yield of soybean cultivars grown in low-fertility Fluvisols. The experiment was conducted during the 2021/2022 growing season in Campos dos Goytacazes, Rio de Janeiro, using a strip-plot design with four soybean cultivars and two soil amendment placement strategies: surface application without tillage and incorporation through tillage. Soil chemical attributes, nodulation, nutrient uptake, and yield components were assessed. Incorporated application significantly increased soil pH, reduced Al³⁺ toxicity, and enhanced Ca²⁺, Mg²⁺, P, and K⁺ availability compared to surface application. Nodulation responses varied among cultivars, with incorporated treatments promoting up to 40% greater nodule biomass. Although primary root length was not affected, incorporation stimulated secondary root development and nutrient uptake, leading to approximately 50% higher pod number and grain yield. Overall, incorporating lime and gypsum through soil tillage was more effective than surface application in improving soil fertility, enhancing nodulation, and increasing soybean productivity under the conditions evaluated in this study. These findings suggest that lime and gypsum incorporation can represent an important management strategy for improving soybean production in degraded sandy soils. Full article

Meadow arnica is a valuable medicinal plant, used in both the pharmaceutical and cosmetic industries. The aim of the study was to determine the influence of arbuscular mycorrhizal fungi (AMF) on the development, yield, and quality of flower heads (raw material) of meadow arnica grown in an organic farming system. The inoculation of plants with AMF improved the mass of above- and underground organs, including the mass of raw material, as well as the content of chlorophylls and general sugar in the leaves, followed by enhanced starch storage in the roots. The content of phenolics in the raw material was determined using high-performance liquid chromatography (HPLC). The following flavonoids were assessed here: cynaroside, rutin, hyperoside, cosmosiin, astragalin, and diosmetin, as well as the phenolic acids: neochlorogenic, chlorogenic, caffeic, ferulic, rosmarinic, cichoric, 3,4-di-O-caffeoylquinic, and 1,5-dicaffeoylquinic acids. The contents of these substances were higher in non-inoculated plants than in inoculated ones, which contradicts most studies conducted to date on medicinal and aromatic plants. Nevertheless, the results are interesting primarily because of the beneficial developmental changes in inoculated plants, as evidenced by a significantly higher mass of arnica flower heads, more efficient uptake of mineral nutrients from the soil, and lower nitrogen levels in aboveground organs. Full article

Cadmium (Cd) is a potentially toxic element that impairs plant growth and threatens food safety and human health. This study aimed to investigate the effects of sulfur (S) supplementation on Cd uptake and tolerance in rice under hydroponic conditions. Rice seedlings were exposed to Cd stress and treated with S at different concentrations. Physiological traits, oxidative damage markers, thiol compounds, and ionomic profiles in rice plants were assessed. S supplementation reduced Cd-induced growth inhibition, restoring plant biomass. Although Cd accumulation increased with S treatment, it was accompanied by enhanced antioxidant responses, scavenging reactive oxygen species (ROS) and malondialdehyde. S application increased the production of thiol-containing compounds, including γ-glutamylcysteine, glutathione, and phytochelatins, which helped chelate Cd and sequester it in vacuoles, particularly in roots. Additionally, S supplementation altered the essential nutrient composition in rice tissues, particularly the uptake of N, P, and K, while influencing levels of Ca, Mg, and other essential elements. S supplementation enhanced rice tolerance to Cd stress by reestablishing ROS balance, activating thiol-based detoxification pathways, and regulating mineral nutrient balance. Furthermore, sulfur (S) exhibited a dual effect in plants, enhancing cadmium (Cd) uptake while also promoting its detoxification, underscoring its role in improving crop resilience in contaminated soils. Full article

SHORT INTERNODE (SHI)-related sequence (SRS) transcription factors are plant-specific zinc-finger proteins increasingly implicated in growth and abiotic stress responses. Despite their diverse vital role in plants, they are largely unexplored in bread wheat. In this study, we identified 15 TaSRS genes and classified them into five homoeologous groups in the bread wheat genome. Each TaSRS protein consisted of conserved RING-like zinc-finger and IGGH domains. The synteny and phylogenetic analyses provided insight into the evolutionary divergence and conservation of TaSRS proteins. Promoter analysis revealed the presence of stress-responsive cis-regulatory elements along with various transcription factor binding sites, indicating their plausible roles in drought and salinity stress responses and signalling. Additionally, the predicted regulation of a few TaSRS genes through certain miRNAs involved in hormone and stress responses, plant development, and nutrient uptake suggested their diverse functions. In silico protein–protein interaction and gene ontology analyses further anticipated an association of TaSRS proteins with organ development and hormone and stress response. High-throughput transcriptomic profiling revealed differential expression of TaSRS genes across various vegetative and reproductive stages and abiotic stress conditions. The qRT-PCR analyses confirmed the stress-responsive role of TaSRS1-1D, TaSRS2-3D, TaSRS4-7A, and TaSRS5-7A under drought and salinity conditions. These results indicated the potential role of TaSRS genes in stress adaptation and opened up opportunities for their detailed functional characterization and applications in the development of salinity and drought resilience in crops. Full article

This research evaluated the efficacy of using two types of biochar (non-modified and acidified) from date palm residues (fronds, leaves, pits) as soil amendments for enhancing soil fertility and maize growth. These biochars were produced through slow pyrolysis under oxygen-limited conditions at 500 °C. Our innovative approach was to minimize gas emissions by converting smoke into liquid fertilizer (LS), which was expected to improve seed germination and early plant growth stages. To assess this aim, a completely randomized experiment was conducted under lab conditions, in which 10 maize seeds were placed on double filter papers in Petri dishes and then exposed to seven concentrations of LS (0.0, 0.01, 0.10, 1.0, 10 and 100%, using distilled water for dilution v/v). The LS contains nutrients and bioactive compounds that may enhance seed germination and early plant growth at low concentrations, whereas higher concentrations may cause phytotoxic effects. Results showed that liquefied smoke at 0.1% increased the absolute percentage of maize germination from 75% (control) to 100% and achieved the highest root length of 9.80 cm. Acidified biochars at 5% reduced soil pH from 8.87 to 8.12 and enhanced potassium availability to 87.93 mg kg⁻¹. Conversely, the non-modified biochars contributed to further increases in soil organic matter (up to 1.02%), nitrogen, and phosphorus. In addition, the application of acidified leaf biochar (5%) enhanced maize shoot growth by 133%, chlorophyll content by 39%, and potassium uptake by 110%. This research establishes a scalable approach for converting agricultural waste into climate-resilient resources, effectively addressing soil degradation in arid environments, boosting crop resilience, and furthering the objectives of a circular bioeconomy. Full article

The majority of terrestrial plant species establish below-ground interconnections via arbuscular mycorrhizal (AM) mycelium, thereby forming extensive common mycorrhizal networks (CMNs). CMNs serve as critical infrastructure for nutrient acquisition, mediating soil nutrient capture and distribution. In nitrogen-fixing plants, phosphorus (P) transport is particularly dependent on functional CMNs. The rapid expansion in graphene oxide (GO) production and its broad application have raised significant ecological concerns, particularly regarding its potential impacts on terrestrial ecosystems. Despite these concerns, the impact of GO on P transport dynamics within legume–arbuscular mycorrhizal fungi (AMF) symbioses remains critically scarce. This study established a symbiotic system using the model nitrogen-fixing legume Medicago sativa L. and AMF. This experimental system enabled a comprehensive assessment of GO effects on rhizosphere P mobilization, plant P acquisition, CMNs architecture, fungal community composition, and expression of key P transporter genes. Our results demonstrated that high GO concentrations significantly altered rhizosphere properties, increasing pH while reducing organic acid content and alkaline phosphatase activity. Furthermore, GO exposure significantly inhibited root growth, mycorrhizal colonization rates, and plant P acquisition efficiency. Additionally, GO exposure altered AMF community composition, reduced rhizosphere microbial diversity, and suppressed P metabolism gene expression. Specifically, 0.6% GO induced significant downregulation of MsCS and GigmPT by 83.5% and 62.3%, respectively. This indicates that GO impairs plant P uptake by disrupting the core pathway involving GigmPT and MsCS, triggering P stress in M. sativa. Collectively, these findings provide compelling evidence that GO exposure disrupts legume–AMF symbiotic integrity, ultimately impairing P transport efficiency. Full article

Background: Phytolith-occluded carbon (PhytOC) is highly stable and constitutes an important long-term carbon pool in agroecosystems, particularly in nutrient-poor, sandy soils. Silicon (Si) uptake by plants is strongly associated with phytolith formation, with Si accounting for up to 90% of phytolith composition. However, the role of Si fertilization in enhancing PhytOC sequestration under field conditions remains insufficiently quantified. Integrated fertilization strategies supporting sustainable development in climate-resilient agriculture can enhance biological carbon sequestration by increasing phytolith formation and phytolith-occluded carbon accumulation, thereby improving the carbon sink potential of cereal-based agroecosystems. Methods: A field experiment was conducted to assess phytolith and PhytOC accumulation in barley biomass under different fertilization regimes, including foliar silicon application using the liquid immune stimulant Optysil and compost fertilization. Phytolith content was determined separately for grain and straw, and PhytOC stocks were converted into CO₂ equivalents to estimate annual sequestration potential. Results: Barley produced substantial amounts of phytoliths, with consistently higher concentrations in straw than in grain. Phytolith content ranged from 18.46 to 21.28 mg g⁻¹ DM in grain and from 27.89 to 38.97 mg g⁻¹ DM in straw. Depending on fertilization treatment, annual carbon sequestration through PhytOC ranged from 16.86 to 55.17 kg CO₂ equivalents ha⁻¹. Foliar silicon application increased PhytOC accumulation in barley biomass by up to threefold compared with treatments without Si. Conclusions: The results demonstrate that optimizing silicon fertilization can substantially enhance carbon sequestration in cropping systems via phytolith formation and PhytOC stabilization. Given the dominant role of cereals in crop rotations and their high phytolith-producing capacity as monocotyledonous plants, Si-mediated PhytOC sequestration represents a promising pathway for strengthening soil carbon storage and contributing to climate change mitigation. Full article