Search Results (1,870)

Soybean is a critical economic, oil and industrial raw material crop, yet its production is often hindered by pathogen infection and pesticide residues. This study explored the synergistic effects of Rhizophagus intraradices and mycorrhizal helper bacteria (MHB) on AMF colonization, AMF spore density, total number of bacterial colonies, soybean growth, root rot disease index, and carbendazim residues. Hydroponic and pot experiments were conducted using a completely randomized design (CRD) with five biological replicates per treatment; after 30 days of growth, three replicates were randomly selected for all measurements. Results showed that inoculation with microbial agents, particularly co-inoculation, increased soybean biomass, reduced disease index, and decreased carbendazim residues. In the hydroponic experiment, co-inoculation increased plant height, aboveground fresh weight, and underground dry weight by 64.28%, 78.13%, and 109.09%, respectively, and decreased carbendazim residues by 71.84% relative to the carbendazim-alone group. In the pot experiment, co-inoculation reduced carbendazim residues by 81.25% and root rot disease index by 45.56% compared with the carbendazim-alone group. Correlation analysis showed a strong positive correlation (p < 0.001) between carbendazim degradation in hydroponic and pot systems, indicating stable degradation function across environments. Co-inoculation of R. intraradices and MHB synergistically promotes soybean growth, suppresses root rot, and reduces carbendazim residues, providing a theoretical basis for developing functional microbial inoculants for safe and green soybean production. Full article

In the future, agriculture will need better irrigation management options to produce more food and decrease its air and water pollution contributions. Hydroponic systems conserve water over field production, but up to 50% of applied irrigation could be discharged from open-drain systems. TVPD is an evapotranspiration model developed for greenhouse production, particularly for hydroponics. In this study, we calibrate and evaluate TVPD on environmental and evapotranspiration data from hydroponic tomato production and compare predictions to those of random forest (RF) and K-nearest neighbors (KNN). Using five time-ordered data splits, we sought to gauge prediction accuracy for data-limited settings, where the model needs to be implemented with the least calibration time possible, and we evaluated TVPD, RF, and KNN with a 10-fold cross-validation to assess overall model robustness. Across the five data splits, TVPD produced more accurate predictions (r²: 0.86 to 0.90; RMSE: 0.1739 to 0.5796 L tray⁻¹) than RF (r²: 0.06 to 0.73; RMSE: 0.7354 to 2.0505 L tray⁻¹) and KNN (r²: 0.06 to 0.59; RMSE: 0.7694 to 1.7090 L tray⁻¹). With calibration on only the first five days of data, TVPD was able to produce acceptable predictions (r² = 0.87, RMSE = 0.5796 L tray⁻¹). The mean r² for a 10-fold cross-validation was 0.81 for TVPD, 0.88 for RF and 0.81 for KNN, and mean RMSE values were slightly better for the cross-validation for RF (0.4970 L tray⁻¹) and KNN (0.4968 L tray⁻¹) than for TVPD (0.5922 L tray⁻¹). Overall, TVPD could be a useful model to predict evapotranspiration for irrigation management and could decrease the volume of discharged hydroponic waste solution. Full article

In citrus production, there is an absence of established standards of critical Nickel (Ni) content for deficiency, sufficiency, and excess, which could be used to determine the nutritional status of plant Ni. In this study, to explore the critical Ni concentrations for deficiency and excess, we conducted a hydroponic pot culture experiment and investigated the effects of Ni levels on flower and fruit development, dry weight, and nutrient accumulation of Newhall navel orange. We found that 0.8 and 6.4 mg L⁻¹ of solution Ni were the turning point concentrations of Ni deficiency and excess for plants, respectively. Solution Ni deficiency (0 to 0.8 mg L⁻¹ of Ni) tended to promote vegetative growth and increase the dry weight of new leaves, but suppress flower bud number and fruit development. It also significantly promoted the accumulation of N, P, K, Ca, and Mg in old leaves and N and K in roots, but significantly reduced that of Fe, Mn, and Zn in roots. Excess solution Ni (6.4 to 12.8 mg L⁻¹ of Ni) reduced the water content of fruit peel and was accompanied by fruit cracking during the fruit expansion period, inhibited new leaf growth and whole plant biomass or dry weight, and significantly decreased nutrient accumulation in roots. Equations of dry weight and solution Ni levels for each plant organ were established, showing that 3.93 to 4.72 mg L⁻¹ of Ni was the sufficient concentration of solution Ni for the growth and development of Newhall navel orange, with the corresponding range of Ni contents in new and old leaves being 17,87 to 20.42 and 10.24 to 11.64 mg kg⁻¹, respectively. These findings provide reference for the recommended range of Ni sufficient for citrus growth. Full article

Developing sustainable strategies for natural resource management and conservation under shifting climatic scenarios is increasingly necessary due to exacerbated abiotic stresses, such as salinity. Under salt stress, several negative effects are observed in plants, particularly in leafy vegetables such as lettuce (Lactuca sativa L.). To mitigate the effects of saline stress from brackish water, several strategies have been adopted, including hydroponic cultivation. Therefore, this study aimed to determine the effects of variations in nutrient solution concentration and volume per lettuce plant cultivated in a nutrient film technique (NFT) hydroponic system using brackish water. The experiment was conducted using a randomized complete block design in a 2 × 2 × 2 factorial scheme, combining two levels of water electrical conductivity (ECw of 0.3 and 5.0 dS m⁻¹), two nutrient solution concentrations (NSC of 50 and 100%), and two nutrient solution volumes (NSV of 1 and 2 L plant⁻¹), with four replications. Growth, production, and water productivity variables were evaluated at 20 and 25 days following the imposition of treatments. The responses of the variables to saline stress varied according to the evaluation period (20 and 25 days), depending on the NSC and NSV levels. At the end of the 25-day cycle, it can be concluded that for lettuce cultivation using brackish water, the NSC can be reduced to 50% and provide an NSV of 2 L plant⁻¹. Under these growing conditions, leaf fresh matter production loss was approximately 40% lower than under cultivation without saline stress, which yielded 144.11 g plant⁻¹ under 100% NSC and an NSV of 2 L plant⁻¹. In contrast, water productivity of fresh matter was similar, at 78.68 and 76.55 g L⁻¹, respectively. Full article

The production of plant-made pharmaceuticals (PMPs) using transgenic rice in controlled environments requires high protein yields to offset operational costs. Unlike other crops, rice has a high demand for silicon (Si). While rice accumulates Si, practical and stable methods for Si supplementation in hydroponic systems are limited by pH instability and nutrient imbalances. In this study, we developed a simple, passive strategy to supply Si by submerging silica-hydrogel fertilizer (SiHF) in the nutrient reservoir. Compared with traditional silicon sources, this approach does not exacerbate pH instability and minimizes the risk of nutrient imbalances. We evaluated its effects on plant growth, yield, phenology, and protein productivity in hydroponically grown rice. SiHF markedly increased shoot biomass and grain yield, with the optimal SiHF concentration identified at 500 g/10 L. Although root dry weight decreased, the water uptake efficiency per unit root mass significantly increased, promoting greater biomass allocation to shoots. The heading stage was advanced by up to 4 days (e.g., from 54 to 50 days) across different concentration groups. Regarding grain quality, protein concentration decreased, likely due to the dilution effect of the substantial increase in grain yield. However, the total protein yield per plant increased 1.98-fold, without remarkably altering the protein composition profile. Ultimately, this SiHF-based method of Si supplementation optimizes biomass allocation and total protein productivity in rice while accelerating the reproductive transition, without requiring complex nutrient management. This approach offers a practical strategy for establishing a foundational baseline for future PMP production efficiency in rice-based plant factory systems. Full article

Understanding the ecological impacts of nanoplastics requires evaluation metrics beyond conventional mass-based concentrations. In this study, we investigated the generation, characterization, and phytotoxic effects of environmentally relevant plastic particles in hydroponically grown lettuce (Lactuca sativa), focusing on particle size, shape, and number concentration. Low-density polyethylene (LDPE) was degraded using an advanced oxidation process, demonstrating that substantial oxidative degradation is required for the formation of nanoplastics; the resulting LDPE particles exhibited a broad size distribution ranging from the nanoscale to the micrometer scale, containing nanoscale domains (peak size ~20 nm, average size ~30 nm), and showed predominantly ellipsoidal morphologies derived from cross-linked polymer regions. In contrast, polystyrene (PS) particles of defined sizes (~600 nm and ~2000 nm) were prepared via mechanical fragmentation, exhibiting sharp-edged, flake-like morphologies. Laser scanning microscopy revealed uptake and translocation of LDPE particles from roots to aerial tissues, whereas larger PS particles showed limited transport. Growth inhibition analysis based on particle number concentration (10¹⁰–10¹⁷ particles/mL) showed a stepwise concentration–response relationship for LDPE particles, with inhibition levels increasing from approximately ~30% at low concentrations to high levels of inhibition at the highest concentrations In contrast, PS particles caused significant root damage (e.g., clear surface disruption observed in microscopy) and growth inhibition (~30–40%) even at relatively low number concentrations (~10¹⁰–10¹² particles/mL), likely due to their sharp-edged morphology. Overall, plant responses to plastic particles were governed by an interplay of size, shape, and number concentration, highlighting the importance of particle morphology and concentration metrics in agroecosystem risk assessment. Full article

Water limitations in the Brazilian semi-arid region require saline water utilization. Hydroponic cultivation combined with salicylic acid (SA) elicitation represents a strategy to manage salt stress in cherry tomatoes. This study evaluated the effects of foliar SA application on the production and quality of cherry tomatoes under saline nutrient solutions. An NFT hydroponic greenhouse experiment at UFCG, Pombal, Brazil, evaluated five nutrient solution salinities (ECns: 2.1, 2.6, 3.1, 3.6, and 4.1 dS m⁻¹) and five SA concentrations (0, 0.8, 1.6, 2.4, and 3.2 mM) in a split-plot design with three replications. SA concentrations from 1.3 to 3.2 mM enhanced fruit diameter, fruit number, average weight, and yield under baseline salinity (2.1 dS m⁻¹). At 3.2 mM, SA functioned as an optimal ratio regulating nutritional quality, increasing titratable acidity and ascorbic acid under 2.1 and 2.6 dS m⁻¹, respectively. Conversely, high salinity (4.1 dS m⁻¹) established a promotion pattern on soluble solids, maturity index, and flavonoids, while reducing yield components by up to 58.3%, demonstrating explicit operational limitations of SA under severe stress. These baseline findings validate the applicability of SA within specific salinity thresholds, establishing a foundational framework for subsequent physiological profiling, fruit quality characterization at harvest, and commercial greenhouse upscale validation. Full article

Choline-based ionic liquids (ILs) have emerged as promising candidates for application in multifaceted avenues, including electrochemistry, biomaterials, and environmental remediation technologies. However, their regulatory effects on the growth of agricultural plants have rarely been discussed. In this study, 14 choline–fatty acid ILs ([Chl][FA] ILs) containing different FA anions were synthesized, and their effects on the maize growth were investigated. Hydroponic experiments revealed that low concentrations (20 mg/L) of dicarboxylic acid-based [Chl][FA] ILs (e.g., choline pentane diacid [Chl][Pent]) significantly promoted maize root and shoot biomass, whereas higher concentrations inhibited it. Specifically, [Chl][Pent] enhanced chlorophyll content without altering Fv/F₀, upregulated nitrate reductase (NR) and glutamine synthetase (GS) activities, and stimulated the expression of key nitrogen metabolism (NR and GS) and photosynthetic (Rubisco) genes. Pathway analyses of differentially expressed genes indicated that [Chl][Pent] was associated with the upregulation of nitrogen and glycerophospholipid metabolism. [Chl][Pent] increased the average grain yield by 6.88% over two years compared to CK. Field application of [Chl][Pent] increased grain yield and protein accumulation relative to both control and choline chloride treatments. Overall, these findings demonstrate the potential of dicarboxylic acid-based [Chl][FA] ionic liquids as eco-friendly biostimulants for enhancing crop growth, yield, and quality. Full article

A comprehensive assessment of the effect of different light spectra on the growth, development, and nutritional composition of Mentha longifolia L. cv. “Vesenniy Aromat” (mint) and Melissa officinalis L. cv. “Limonnyy Aromat” (lemon balm) grown in hydroponic conditions in closed artificial agroecosystems was conducted. The growing period was 75 days for mint and 87 days for lemon balm. The photon flux density (PFD) in the range of 400–800 nm was ~140 µmol·m⁻²·s⁻¹, and the light period was 16 h. Five lighting options and four spectral color ratios were used in the treatments—blue (B), green (G), red (R), and far red (FR), and 3:66:27:4 (HPL (control)); 16:42:39:3 (White LED); 96:3:1:0 (Blue LED); 1:1:98:0 (Red LED) and 25:3:72:0 (Red + Blue LEDs)—in a growth chamber for cultivation with controlled environmental conditions. Under White LED, M. longifolia L. plants were compact, with a large number of leaves and high plant biomass. The effect of Red + Blue LEDs had a general trend for M. longifolia L. and M. officinalis L. in terms of improving plant morphology (leaf area, number of leaves, and plant biomass), elemental composition (contents of potassium, magnesium, calcium, and phosphorus) and reducing the accumulation of nitrates in the plants. Blue spectrum lighting significantly affected the content of leaf pigments, quercetin, rosmarinic acid, and essential oils of mint and lemon balm. Red spectrum lighting significantly reduced the accumulation of nitrates in the vegetative mass of plants. Precise regulation of metabolic processes, taking into account the spectral quality of light, can contribute to improving the economic efficiency of the growth, development, and productive potential of mint and lemon balm grown under controlled conditions. Full article

Wheat (Triticum aestivum L.), a key grain food crop worldwide, faces increasing threats from combined abiotic stresses exacerbated by climate change. However, the comprehensive effects of drought, salinity, and high-temperature pressure on wheat seedlings remain poorly understood. Using the cultivar “Yannong 1212”, we conducted hydroponic experiments to investigate the physiological, morphological, antioxidant, osmoregulatory, membrane lipid peroxidation, and molecular responses of wheat seedlings to single and combined stresses, and then conducted multivariate statistical analyses. The results showed that drought or salt stress inhibited seed germination in a concentration-dependent manner. However, the combined stresses significantly inhibited germination and seedling growth, leading to leaf chlorosis, chlorophyll degradation, stomatal closure, and chloroplast damage. Physiologically, the combined effect of multiple stresses induced excessive ROS and MDA accumulation, promoted proline and soluble sugar synthesis, and triggered the dynamic responses of antioxidant enzymes. Drought stress increased SOD, POD, and CAT activities, whereas salt stress had the opposite effect, and combined stresses further increased SOD and POD activities, but reduced CAT activity. Additionally, stress-responsive genes were rapidly upregulated. Multivariate analyses confirmed that the combined stress of drought and heat was the most damaging. These findings explain the synergistic damage mechanisms of combined stresses, providing a theoretical basis for genetic improvement of wheat’s stress tolerance. Full article

High summer temperatures can reduce growth and flower quality in standard chrysanthemum, while whole-greenhouse cooling requires substantial energy input. This study evaluated whether localized root-zone cooling could improve growth and suppress open-center malformed capitula in standard chrysanthemum ‘Baekgang’ while considering energy use. Rooted cuttings were grown in a commercial hydroponic greenhouse during summer and subjected to a non-cooled control (NC) or root-zone cooling activation thresholds of 28 °C (HT), 25 °C (MT), or 22 °C (LT). Root-zone temperature, vegetative growth, gas exchange, flower quality, open-center incidence, and electricity consumption were measured. Mean root-zone temperatures were 27.8 °C in NC, 26.6 °C in HT, 24.4 °C in MT, and 23.3 °C in LT. Root-zone cooling improved vegetative growth, particularly stem diameter and shoot and root biomass, whereas leaf-level gas-exchange parameters were not consistently affected. Open-center incidence was highest in NC (67%) and was reduced to 33%, 11%, and 33% in HT, MT, and LT, respectively. Electricity consumption was 321, 783, and 1088 kWh bed⁻¹ in HT, MT, and LT, respectively. These results indicate that moderate root-zone cooling, particularly MT, provides a practical balance between flower quality and energy use for summer chrysanthemum production. Full article

Nanotechnology has attracted increasing attention in agricultural and environmental research, but the biological effects and potential risks of nanoparticles based on non-essential elements remain insufficiently understood. This study investigated the physiological and biochemical responses of rice (Oryza sativa L.) seedlings to yttrium oxide nanoparticles (Y₂O₃ NPs) and zirconium oxide nanoparticles (ZrO₂ NPs) at 5, 25, and 100 mg/L under hydroponic conditions. The results showed that neither Y₂O₃ nor ZrO₂ NPs significantly affected visible growth traits or SPAD-based leaf chlorophyll status, suggesting that seedling morphology and leaf greenness remained relatively stable during exposure. However, both nanoparticles induced distinct biochemical responses. Y₂O₃ NPs caused root-level stress-like responses, including increased malondialdehyde (MDA) accumulation and suppressed peroxidase (POD) and catalase (CAT) activities under specific exposure conditions. In contrast, ZrO₂ NPs were more closely associated with the activation of antioxidant defenses, particularly through enhanced POD activity and increased root CAT activity. Inductively coupled plasma mass spectrometry (ICP-MS) analysis further showed that Y and Zr were mainly retained in roots, with root Y reaching 5014.12–11,255.05 mg kg⁻¹ dry weight (DW) under Y₂O₃ NP exposure and root Zr reaching 189.68 mg kg⁻¹ DW under high-concentration ZrO₂ NP exposure. Bio-transmission electron microscopy (bio-TEM) supported the root-dominant localization of nanoparticle-associated electron-dense aggregates. These findings indicate that Y₂O₃ and ZrO₂ NPs exert material-specific effects on rice seedlings, with root accumulation and antioxidant regulation serving as more sensitive indicators than visible growth traits. However, further research is needed to clarify the long-term environmental fate of Y₂O₃ and ZrO₂ NPs and to assess their potential ecological and food safety risks in agricultural systems. Full article

Cadmium (Cd) and polystyrene (PS) microplastic co-contamination in agricultural soils poses a potential threat to food security. Some functional microorganisms in soil can alleviate the dual stress of Cd and PS on crops. In this study, a biofilm-forming bacterium, Enterobacter sp. W5, was isolated from heavy metal-contaminated rhizosphere soil. Strain W5 exhibited Cd removal efficiency (46.3%) and strong biofilm-forming capacity (OD₅₇₀ = 5.05), and it effectively colonized PS microplastic surfaces. XPS analysis detected bacterial functional groups (C–O–C, C=O) and PS-associated signals (O–C=O), which may act synergistically in Cd²⁺ adsorption. Furthermore, XPS and XRD analyses revealed the presence of Cd-containing precipitates (including CdS, CdO, and Cd₃(PO₄)₂). In hydroponic wheat experiments, W5 inoculation alleviated Cd-PS combined stress, thus significantly promoting plant growth and reducing Cd accumulation by 22.6% in roots and by 34.2% in aboveground tissues. Subcellular distribution analysis revealed that W5 enhanced Cd retention in root cell walls, thereby limiting its translocation to active cellular compartments. Proteomic analysis identified a set of 11 consistently downregulated proteins, including A0A3B6HQ68 and A0A3B6KJV9, which were enriched in secondary metabolite biosynthesis pathways. Bioinformatic analysis suggests that these proteins may be associated with Cd stress responses, though their exact roles remain to be verified. Collectively, this study provides a valuable microbial resource and mechanistic insights into the application of biofilm-forming bacteria for mitigating combined heavy metal–microplastic pollution in agricultural systems. Full article

Partial recirculation can reduce water and fertilizer inputs in indoor strawberry production, but excessive reuse may cause ion-specific nutrient-solution drift. We compared 0%, 30%, and 50% recirculation of gross supplied water in a closed two-tier indoor aeroponic system for ‘Seolhyang’ strawberry over two cultivation years. Each treatment was evaluated as a descriptive operational comparison across the cultivation years, with no independent block-level replication within each cycle. Each recorded run represented directly measured harvest from three internal blocks (480 plants; 25 m²), converted to per-block values (160 plants; 8.33 m²). All the treatments used a stage-adjusted Yamazaki-based nutrient solution, common EC/pH targets, and a gross irrigation supply of 54.0 m³ cycle⁻¹ for the three-block run. Return-water chemistry was analyzed biweekly. Mean yield was 71.7 kg block⁻¹ in the non-recirculating control, 70.0 kg block⁻¹ at 30% recirculation, and 41.7 kg block⁻¹ at 50% recirculation, equivalent to 0.45, 0.44, and 0.26 kg plant⁻¹. Fresh make-up water demand was 18.0, 12.6, and 9.0 m³ block⁻¹ cycle⁻¹, respectively. Increasing reuse depleted P and K; accumulated Ca, Mg, and Na; and narrowed K:Ca and K:(Ca+Mg) ratios. Our results establish 30% recirculation as the threshold that maximizes resource recovery without compromising yield. Full article

Conventional hydroponic systems, although resource-efficient, face significant sustainability challenges due to the discharge of nutrient-rich effluents, resulting in severe environmental pressures. In alignment with the European Union’s “Farm to Fork” strategy, innovative circular economy approaches are required to decouple crop production from environmental degradation. This study evaluates a novel Cascade Hydroponic System (CHS), designed to maximize resource utility by recovering and reusing the drainage from a primary salt-sensitive crop (cucumber) to a secondary, more salt-tolerant cultivation (melon). A comparative Life Cycle Assessment (LCA) is performed in accordance with the Product Environmental Footprint Category Rules (PEFCRs), utilizing primary operational data and direct monitoring of nutrient concentrations in the system’s effluent. The convergence of these elements establishes the novelty of this study. The CHS is benchmarked against a conventional Separated Hydroponic System (SHS) for a functional unit (FU) defined as “the simultaneous production of 1.0 kg of cucumber and 1.0 kg of melon”. The CHS demonstrated lower characterized impacts compared to SHS across all 16 assessed Environmental Footprint categories under the examined pilot-scale conditions. The key findings include reductions of 65.7%, 41.8%, and 30% in Water Use, Climate Change, and Freshwater Eutrophication scores, respectively. Based on the normalization results, the CHS revealed a 58% lower total environmental footprint score compared to SHS. Process contribution analysis indicates that the marked decrease in the environmental burden is associated with the use of fertilizers. While these inputs represent a significant share of the conventional system’s impact scores, their contribution was substantially lower in the CHS. Although based on pilot-scale operational data from a single crop cycle, the results highlight the considerable environmental potential of cascading nutrient reuse configurations, thus enhancing resource use efficiency and mitigating the associated environmental impacts while also contributing novel empirical knowledge to a field that has been limitedly studied. Full article