Search Results (583)

The growing demand for Critical Raw Materials (CRMs) requires mining practices that align with sustainability and environmental, social, and governance (ESG) principles, while mining training increasingly benefits from advanced digital tools. Virtual Reality (VR) can provide high-resolution site representations that support both interactive learning and data-oriented analysis without operational risk. This study presents a VR-based framework for the quantitative assessment of pit lake rehabilitation using Virtual Excursions (VEs) developed from panoramic imagery and supported by machine-learning correction. High-resolution 360° panoramic images were used to extract geometric characteristics of a rehabilitated pit lake at the LARCO GMMSA Euboea mine site, Greece, including surface area, shoreline length, mean diameter, and maximum diameter. These image-derived estimates were validated against ground-truth data from field surveys and mine-closure documentation. To reduce systematic deviations associated with panoramic image measurements, a supervised multiple linear regression model was applied as a correction step. Validation based on Root Mean Square Error (RMSE) and the coefficient of determination ($R^2$) showed substantial improvement of the corrected estimates relative to the uncorrected image-based measurements. The results demonstrate that panoramic VR imagery can support site-specific quantitative environmental assessment in addition to its educational value. Although the present findings are limited to a single pit lake case study, the proposed workflow provides a structured basis for integrating immersive visualization, image-based measurement, and regression-based correction in post-mining rehabilitation assessment. Full article

The coupling of water and nitrogen (N) availability critically constrains alpine plant growth and ecosystem productivity, yet the mechanistic links between plant functional traits and resource use efficiencies (rain use efficiency, RUE; nitrogen use efficiency, NUE) along precipitation gradients remain unclear. This study aimed to test whether coordinated shifts in plant functional traits are associated with spatial variation in RUE and NUE across a precipitation gradient on the Changtang Plateau. Here, combining transect surveys with N-addition experiments on the Changtang Plateau, we measured biomass and leaf/root functional traits on four typical grasslands and analyzed the spatial variations in RUE, NUE, and fertilizer use efficiency (FUE). Our results demonstrated contrasting spatial patterns: with increasing precipitation, soil resource availability, community species richness, and biomass significantly improved, and vegetation shifted from a water-conservative strategy in arid regions to a nutrient-efficient strategy in humid regions. FUE increased with precipitation (p < 0.05), with low-dose nitrogen addition exerting more pronounced effects in humid regions, indicating greater responsiveness to fertilization. This transition in resource use patterns is underpinned by a coordinated divergence in functional traits: as water limitation eases, communities exhibited decreasing specific root length (high specific root length, SRL) coupled with increasing specific leaf area (high specific leaf area, SLA) along the gradient. Our findings demonstrate that functional trait variation is associated with the optimization of resource acquisition across environmental gradients. These results provide a mechanistic basis for adaptive management in climate-sensitive alpine biomes, where differentiated grassland management schemes may enhance ecosystem productivity—water conservation and reduced disturbance in arid regions, with moderate low-dose nitrogen fertilization and species diversity protection in humid regions. Long-term ecosystem responses to such management approaches require further investigation. Full article

Atmospheric nitrogen deposition is increasing globally, making it essential to understand how leaf and root traits vary and interact to shape plant ecological strategies under changing environmental conditions. We conducted leaf and root traits of eight perennial grasses (rhizomatous and bunchgrass species) in a field experiment conducted in the Songnen grassland, incorporating control and nitrogen addition treatments (10 g m⁻² yr⁻¹). Nitrogen addition significantly altered leaf and root trait expression and promoted biomass accumulation in both life forms. Specifically, nitrogen addition increased assimilation rate (An; 19.4 and 20.7%), leaf nitrogen content (LNC; 51.5 and 57.8%), specific root length (SRL; 30.1 and 41.1%), and root nitrogen content (RNC; 18.6 and 34.4%), while markedly reducing root tissue density (RTD; 40.2 and 46.6%) of perennial rhizome grass and perennial bunchgrasses. Principal component analysis revealed multiple plant resource strategies reflected by multidimensional variation in leaf and root traits. However, no consistent correlations were detected between leaf and root trait dimensions, and regression relationships differed significantly under nitrogen addition. These results indicate a decoupling of above- and belowground resource acquisition strategies at the local scale. Additionally, we underscore the importance of combining above- and belowground traits to improve predictions of plant performance. Our findings advance understanding of leaf–root trait coordination in perennial grasses and provide insights into plant adaptive strategies in arid and semi-arid regions’ grassland ecosystems experiencing increasing nitrogen deposition. Full article

Low-temperature stress adversely impairs rice germination and seedling establishment. This study assessed a nano-bio-priming strategy using lecithin (L) and silicon dioxide nanoparticles (SiO₂ NPs) to enhance chilling tolerance. Two fragrant rice cultivars (Xiangyaxiangzhan and Meixiangzhan 2) were primed with six combinations of lecithin (0, 50, and 100 μmol·L⁻¹, denoted as L0, L1, and L2) and SiO₂ NPs (0 and 100 mg·L⁻¹, denoted as S0 and S1) and exposed to optimal temperature (25 °C) or low-temperature stress (15 °C). Low-temperature stress delayed germination onset by two days. Combined priming treatments L1S1 and L2S1 significantly alleviated this inhibitory effect. Crucially, cultivar-specific responses were evident in Meixiangzhan 2, where L1S1 increased the germination vigor index by 50.97%. Meanwhile, the effect was less pronounced or inhibitory at normal temperature in Xiangyaxiangzhan. Priming substantially enhanced seedling growth, and L2S1 maximally increased root and shoot length in Meixiangzhan 2 by 55.30% and 15.82%, respectively. Furthermore, biomass accumulation was strongly promoted. L1S1 increased total dry weight and total fresh weight in Meixiangzhan 2 by 19.64% and 23.48%, respectively. Physiologically, priming elevated chlorophyll and carotenoid contents upregulated the activities of superoxide dismutase (SOD), peroxidase (POD), and catalase (CAT), and increased levels of soluble protein and ascorbate (AsA), while maintaining nitrate reductase (NR) activity and hydrogen peroxide (H₂O₂) homeostasis. These physiological improvements were positively correlated with enhanced growth. Our findings demonstrate that co-priming with lecithin and SiO₂ NPs is a potent strategy for enhancing low-temperature tolerance, with efficacy depending on both the treatment combination and rice genotype. Full article

Cassava (Manihot esculenta Crantz) is a nitrogen-efficient crop that can achieve high biomass production on poor soils. However, the mechanisms underlying the response of cassava to nitrogen-deficiency signals and the regulation of nitrogen use efficiency remain unclear. Here, we found that MeCEPD (MeGRXC1) was specifically induced by CEP6 peptides and low nitrate, and showed higher expression in leaves and stems. Overexpression of MeCEPD enhanced cassava’s tolerance to nitrate deficiency by upregulating the expression of MeNRT2.1, MeNRT2.4, and MeRBCS1A, which was manifested as increased root biomass, greater lateral root number, and darker leaf coloration. In contrast, the MeCEPD-edited lines exhibited a statistically significant reduction in root length, plant height, and biomass compared to the wild-type. Additionally, nitrate deficiency accelerated leaf senescence. Furthermore, yeast two-hybrid (Y2H) assay revealed that MeCEPD interacts with the photosynthesis-related MeRBCS1A and lateral root development-related MeLHW, which may regulate nitrogen use efficiency. Unlike its Arabidopsis thaliana homologs AtCEPD1/2 and AtCEPDL2, which interact with AtTGA1/4, MeCEPD does not interact with MeTGA1 yet still upregulates MeNRT2.1 expression. These findings contribute to our understanding of the complex regulatory mechanisms underlying cassava’s adaptation to low-nitrogen conditions and could provide new information for genetic improvement in nitrogen use efficiency in cassava. Full article

Microalgal and cyanobacterial biostimulants are increasingly recognized as sustainable tools for enhancing crop establishment and reducing dependence on synthetic agrochemicals. However, the strain-specific effects of many taxa on seed germination and early seedling development remain insufficiently characterized. This study evaluated the effects of seven microalgal and cyanobacterial suspensions on the germination kinetics and early seedling vigor of cucumber (Cucumis sativus L.). Several strains significantly accelerated germination and enhanced seedling performance relative to the control. Treatment with Coelastrella rubescens BCAC 301 S39, Scotinosphaera lemnae BCAC 113, Vischeria magna UTEX 2351, and Anabaena sp. IT4 significantly reduced mean germination time from 4.50 d to 2.23–2.29 d and advanced the time to 50% germination (T₅₀) from 4.0 to 2.0–2.1 d. These treatments also increased the germination index from 48.32 to 78.17–100.67 and enhanced seedling traits, including root length (32–53%), shoot length (≈29%), leaf length (17–21%), and fresh (30–43%) and dry biomasses (12–22%). Correlation analysis revealed strong positive associations between germination indices and seedling vigor parameters, indicating the faster germination promotes early growth. In conclusion, the results demonstrate that specific microalgal strains can function as effective seed-phase biostimulants, offering a sustainable strategy to enhance germination uniformity, early seedling establishment, and crop productivity. Full article

Saline-alkali stress restricts crop yield by disrupting nutrient and water uptake, ionic balance, and oxidative homeostasis. Although myo-inositol enhances tolerance to abiotic stress, its role in sugar beet (Beta vulgaris L.) under saline-alkali conditions remains unclear. To investigate the effects of exogenous myo-inositol on sugar beet growth under saline-alkali soils, a pot experiment was conducted using six myo-inositol concentrations (0, 0.2, 0.4, 0.6, 0.8, and 1.0 g L⁻¹). Myo-inositol significantly influenced plant performance in a concentration-dependent manner. The 0.6 g L⁻¹ treatment produced the highest shoot and root fresh and dry weights, nearly doubling shoot biomass compared with the control. Shoot N and P contents increased markedly at 0.6 g L⁻¹, while their concentrations remained relatively stable, indicating biomass-driven nutrient accumulation. Myo-inositol reduced Na accumulation while maintaining stable K, Ca, and Mg concentrations, thereby improving ionic balance. Antioxidant capacity was enhanced, with superoxide dismutase and catalase activities significantly elevated. Root total length and surface area increased substantially, whereas specific root length and surface area decreased, suggesting improved root morphological development. Soil alkaline phosphatase activity was also stimulated at higher myo-inositol treatments. Overall, moderate myo-inositol application (with regression analysis indicating an optimum of approximately 0.56 g L⁻¹) improved sugar beet growth through enhanced nutrient acquisition, ionic balance, antioxidant capacity, and root development, offering practical insights for its use as a growth regulator in saline-alkali crop production. Full article

Climate warming and drought often co-occur to form warm–dry climate patterns. However, systematic comparative studies of the responses of invasive plants from different families to their combined effects remain limited. We conducted a greenhouse experiment to investigate the interactive effects of warm (normal vs. warming) and drought (well-watered vs. drought) conditions on the growth, root traits, and competitive performance of 11 invasive plant species from three families (Amaranthaceae, Poaceae, and Asteraceae) growing in competition with native communities. Our results showed that warming did not significantly increase the total biomass of all invasive species combined but significantly promoted biomass accumulation in Poaceae and Asteraceae. Drought consistently reduced the biomass across all invasive species. Notably, a marginally significant interaction effect of warm and drought conditions on the biomass proportion of Amaranthaceae was detected. Specifically, under normal conditions, drought increased the biomass proportion of Amaranthaceae species, whereas under the warming treatment, drought decreased it. Furthermore, root traits of invasive species exhibited clear family level differentiation. Poaceae adopted an expansion strategy by increasing root length and root surface area under warming treatment, Amaranthaceae exhibited a contraction strategy by reducing root investment under drought treatment, and Asteraceae displayed an efficient strategy with increased specific root length under drought treatment. Except for the biomass proportion of Amaranthaceae, no significant interactive effects were found for most other parameters, indicating that the combined effects of warming and drought were primarily additive. Our results revealed that warm, dry climates influence invasive plants in a taxon-specific manner, with different families employing distinct root trait adjustment strategies in response to environmental stress. These findings highlight the importance of family level comparative studies for predicting invasion dynamics and developing targeted management strategies for future climate scenarios. Full article

Soil nutrients and water are often distributed heterogeneously in space, yet how plant roots forage in response to such heterogeneity and how their strategies relate to functional traits remain poorly understood. Here, we conducted an indoor pot experiment manipulating water and nutrient supply in both homogeneous and heterogeneous patch patterns using seedlings of four tree species, focusing on root functional traits and foraging strategies. The results indicate that root foraging behavior exhibits both resource specificity and species specificity: roots tend to proliferate toward nutrient-rich and low-water patches as an adaptive strategy. Although no strict dichotomy was observed between high foraging scale (low precision) and low foraging scale (high precision) strategies under heterogeneous conditions, fine-rooted species (Acer truncatum and Koelreuteria paniculata) exhibited traits leaning toward “precise foraging”, whereas coarse-rooted species (Prunus davidiana and Quercus variabilis) tended toward a conservative “random walk” pattern, with no trade-off between root foraging scale and precision. Root morphological traits exerted significant nonlinear regulation on foraging scale: root biomass foraging scale (FS_RB) correlated positively with root diameter (RD) but negatively with specific root length (SRL) and specific root area (SRA); root length foraging scale (FS_RL) correlated positively with root length (RL), root tip number (RTN), SRL, and SRA. In contrast, root morphological traits could not explain the variation in foraging precision, suggesting that foraging precision constitutes another distinct dimension in root-trait space. In summary, this study provides key insights into the foraging strategies of plant roots in heterogeneous environments, expanding our understanding of the multidimensionality of root functional traits. Full article

Environmental contamination with fluorinated compounds has increased markedly due to their widespread use in industry, medicine, and agriculture. Fluoride ions and fluoroquinolone antibiotics may enter soils through fertilizers, wastewater, and manure application, where they can interact with plant-associated microbial communities. In the present study, we investigated the effects of inorganic fluoride (applied as sodium fluoride, NaF) and the fluoroquinolone antibiotic pefloxacin on the growth and microbiome composition of Eruca sativa L. Plants were cultivated under controlled conditions and exposed for four weeks to NaF or pefloxacin at equimolar concentrations of 10 and 20 µM/kg soil. Morphological parameters, including biomass accumulation, root length, leaf dimensions, and leaf area, were not significantly affected by either treatment. Nevertheless, increased variability of growth traits was observed, particularly in plants exposed to NaF. High-throughput sequencing of the 16S rRNA gene revealed pronounced, treatment-specific alterations in both rhizosphere and phyllosphere bacterial communities. The rhizosphere microbiome was relatively stable at higher taxonomic levels but exhibited selective enrichment of Actinomycetota, including the class Thermoleophilia, under NaF exposure. In contrast, the phyllosphere microbiome showed strong sensitivity to fluoride, with a marked increase in Betaproteobacteria, dominated by Burkholderiales. Changes induced by pefloxacin were weaker and more diffuse. Our results demonstrate that plant-associated microbiomes respond to fluorinated compounds at concentrations that do not induce visible plant stress. The phyllosphere microbiome, in particular, represents a sensitive indicator of fluoride exposure and may serve as an early-warning system for environmental contamination. Full article

This study investigated the combined effects of microbial-inoculated biochar and nitrogen (N) on rice growth and soil properties under saline conditions. A randomized complete block design with three replications was employed to evaluate three factors: (i) salinity level (non-saline, S0; saline, 0.4% NaCl, S1), (ii) biochar type (20 t/ha BC, BF, BB, and BFB), and (iii) nitrogen application rate (60 and 120 kg ha⁻¹). Soil physicochemical and biological properties, along with rice root development, were assessed. Salinity significantly reduced soil organic matter (OM) by 9%, nitrate nitrogen (NO₃⁻-N) by 16%, ammonium nitrogen (NH₄⁺-N) by 8.18%, and available phosphorus (AP) by 6.81%. Soil enzyme activities, including catalase (CAT), acid phosphatase (ACP), polyphenol oxidase (POX), and β-D-glucosidase (BG), decreased by 32.69%, 29%, 39.18%, and 19.44%, respectively, resulting in suppressed root growth compared with non-saline conditions. The combined treatment of microbial biochar (BFB) and N at 120 kg ha⁻¹ (BFB + N120) markedly improved saline soil quality and rice root performance by maintaining a favorable K⁺/Na⁺ balance in roots. Specifically, BFB+N120 increased OM by 145% and 120% compared with N120 and BC alone, respectively, and enhanced NO₃⁻-N, NH₄⁺-N, and soil enzyme activities (CAT, ACP, POX, and BG). These improvements were strongly associated with enhanced root development. Under saline conditions, BFB+N120 increased root dry mass by 429% and 1185.71%, and root length by 63% and 83%, compared with N120 and BC alone, respectively, in the cultivar Jing Liang You 534. Overall, the results demonstrate that microbial-modified biochar combined with nitrogen fertilizer mitigates salt-induced soil degradation by improving physicochemical and biological properties, thereby enhancing nutrient availability, ionic homeostasis, and root growth. This study provides mechanistic insights into the combined role of microbial biochar and nitrogen in the remediation of saline soils. Full article

Nanoparticles have been extensively studied due to their rapid development and increasing application in agriculture; however, the potential of magnetic fields to mitigate the toxic effects of ZnO nanoparticles (ZnO-NPs) remains unexplored. Magneto-priming can enhance seed performance without chemical inputs, contributing to green engineering, resource efficiency, and environmental sustainability. This study assesses the effectiveness of magneto-priming in enhancing triticale tolerance to ZnO-NP stress under both direct seed exposure and soil leachate treatments. Germination performance, seedling growth, root system development, and seedling vigor were assessed to characterize both phytotoxic effects and the mitigating role of magneto-priming. Direct seed exposure to ZnO-NPs reduced germination and slightly promoted root elongation at low doses, reflecting localized phytotoxicity. Magneto-priming increased shoot length by 28%, root length by 13–15%, roots per seed by 13%, and the Seedling Vigor Index (SVI) by 29% under direct exposure, promoting more balanced early seedling development. However, in soil-leachate assays, where nanoparticle mobility and bioavailability were limited, magneto-priming reduced germination, SVI, and shoot length while enhancing root traits, indicating a system-dependent trade-off. Overall, these results highlight that the benefits of magneto-priming in mitigating ZnO-NP stress are context-specific, with clear positive effects under direct exposure but mixed responses under leachate conditions, emphasizing the importance of the exposure pathway in early seedling establishment strategies. Full article

The Lateral Organ Boundaries Domain (LBD) gene family encodes plant-specific transcription factors that play pivotal roles in growth, development, and stress responses. However, a comprehensive genome-wide analysis of the LBD family in watermelon (Citrullus lanatus) has not been conducted until now. In this study, we identified 39 ClLBD genes using the latest watermelon reference genome and systematically analyzed the function of ClLBD2 in root development. These ClLBDs are unevenly distributed across 10 chromosomes except Chr4. Evolutionary analysis grouped the gene family members into six subgroups: Class I (a–e) and Class II. Physicochemical properties and gene structure analysis showed that the ClLBD protein members are tightly conserved. In the promoter regions of ClLBD genes, we identified abundant cis-acting regulatory elements related to abiotic stress and hormone responses. Through RNA-seq analysis from a cucurbit database, we found that several ClLBD genes showed high relative expression in roots, with ClLBD2 being the most highly expressed. Since its subfamily includes AtLBD25, a known root development-related gene, we hypothesized that ClLBD2 might be involved in root development. To validate this, ClLBD2-edited roots were generated using the CRISPR-Cas9 system and Agrobacterium rhizogenes-mediated transformation. Compared to the wild type, the ClLBD2 edited roots exhibited significant reduction in taproot length and lateral root numbers, indicating that ClLBD2 may regulate root development. This study provides the first comprehensive analysis of the LBD gene family in watermelon, offering valuable insights for evolutionary and further functional studies of ClLBD genes. Full article

Drought stress during germination impairs seed germination and seedling development in wheat. Seed germination depends on embryo lipid mobilization for energy supply; however, the molecular mechanisms underlying lipid mobilization in drought stress germination remain unclear. Two wheat cultivars with significant differences in drought resistance, Shannong 28 (SN28) and Xinmai 296 (XM296), were subjected to integrated transcriptomic, metabolomic, and lipidomic analyses to reveal molecular response differences. SN28 exhibited increased root length (RL), while XM296 showed significant decreases in germination energy (GE), vigor index (VI), and single seedling dry weight (SSDW). Multi-omics integration revealed that SN28 maintained efficient lipid mobilization under drought through a distinctive regulatory strategy: suppressing jasmonic acid synthesis to prevent excessive growth inhibition, activating α-DOX1 signaling to maintain defense function, and coordinating these with low expression of ABA signaling factors MYB96 and ABI4 to relieve lipid mobilization suppression. Upregulated lipase and nsLTP genes (TaLTPIe.1, TaLTPIg.1) promoted lipid mobilization, while coordinated activation of arginine–proline metabolism, zeatin biosynthesis, and antioxidant defense pathways provided metabolic support. In contrast, XM296’s extensive inhibition of lipoxygenase enzymes and insufficient lipid mobilization capacity directly underlies its drought susceptibility. These findings indicate that cultivar-specific lipid metabolism patterns are key determinants of germination-stage drought resistance, providing candidate genes for wheat breeding. Full article

A detailed characterization of root system architecture (RSA) and growth dynamics is key to develop stress-resilient maize varieties. We evaluated sixty-five Mediterranean maize inbred lines using automated high-throughput phenotyping under controlled conditions. Shoot and root traits were extracted from imaging data during early vegetative development, revealing significant genotype-specific variation in root biomass-related traits (total root length, total root volume), root architecture (root angle, root system depth, root system width), and relative growth rates. Notably, lines previously classified as heat and drought stress-resilient or stress-sensitive based on above-ground development did not group according to particular root traits, indicating that multiple strategies may underlie tolerance to combined stress. We identified lines with contrasting RSA, including deeper roots, shallower roots, or overall larger root systems, that offer new opportunities for resilience breeding. Our results underscore root traits as critical yet underexploited targets for improving stress resilience and resource efficiency. Full article