Search Results (1,839)

Silicon plays a positive role in plant growth and physiological activities; however, silicon fertilizer application in bamboo remains limited. This study explored the silicon accumulation and photosynthetic capacity of Dendrocalamus brandisii in response to sodium silicate (SS) foliar application across vegetative phenological stages. The results showed that August (shooting stage) and May (branching and leafing stage) were the critical periods for silicon accumulation. SS significantly enhanced the net photosynthetic rate (Pn), chlorophyll content, and photosystem activity (Fv/Fm, Fv′/Fm′), particularly in August and May. Correlation analysis revealed that silicon content was significantly positively correlated with photosynthetic parameters (Pn, chlorophyll a/b) and photoassimilate accumulation (soluble sugar, starch), confirming that silicon optimized leaf light capture and carbon assimilation capacity by promoting phytolith formation. This research provides a theoretical foundation for the application of silicon fertilizers in bamboo forest cultivation. Full article

This study evaluated the effects of incorporating spent mushroom substrates (SMS) derived from Agaricus bisporus, Pleurotus ostreatus, and Lentinula edodes into peat-based growing media on the morphological traits, photosynthetic parameters, and mineral composition of radish and black radish microgreens. Six substrate mixtures were tested, with 2.5–30% SMS and two composting durations (97 and 153 days). The results showed that a low proportion of A. bisporus SMS (2.5–5%) significantly enhanced biomass production, plant length, and leaf area, particularly in radish. In contrast, higher proportions (20–30%) of P. ostreatus and L. edodes SMS, especially when short-time composted, inhibited plant growth and photosynthetic performance (Fv/Fm, PIabs), likely due to phytotoxic compounds, high salt content, or nutrient imbalances. Mineral analysis revealed substantial increases in K, Fe, and Zn accumulation in microgreens grown on selected SMS media, particularly Agaricus 5% and Lentinula 30, while also highlighting the risk of excessive Na or heavy metal content in some treatments. Differences between the species were observed: black radish produced higher dry mass and accumulated more minerals, suggesting greater adaptability to suboptimal substrates. These findings support the potential use of well-composted SMS as a sustainable growing media component for microgreens, provided proper substrate selection, composting, and dosage control are applied. Full article

Gongolaria usneoides is a native brown alga in Europa, known for its high release of phenolics into the water. Rugulopteryx okamurae is a native brown macroalga from Asia but invasive in Europe, causing significant environmental and socioeconomic impacts. It has been observed that in some regions where Gongolaria is present, there is less biomass of Rugulopteryx, and they are often epiphytized by red filamentous algae. The present study aimed to analyze whether phenolics released in the seawater by G. usneoides affect the photosynthetic and biochemical responses in R. okamurae. To analyze the resilience of R. okamurae, algae were cultivated for 5 days in water with different percentages of phenolics released by G. usneoides (exposure phase) (0, 75, 150, 225 and 300 µg mL⁻¹) in laboratory (20 °C, a 12:12 photoperiod, and PAR 190 µmol photons m⁻² s⁻¹ for a period of 115 h) and a period in the sun (4 h), followed 2 days cultured under phenolic-free water (recovery phase). Photosynthetic characteristics (Fv/Fm and ETR) and biochemical composition (phenolic, antioxidant activity, C, N and S) were measured (R. okamurae showed considerable photosynthetic declines without recovery when exposed to high concentrations of phenolics (225 and 300 µg mL⁻¹). It can be inferred that the presence of G. usneoides in nature and the release of phenolic compounds by this alga may be affecting the invasive alga R. okamurae, potentially serving as a natural means to decrease or weaken the invasive species. Full article

Mirabilis expansa root (MER) is an Andean source of starch that could be considered a “lost crop” by the scarcity of its cultivation. Consequently, few studies have reported on its functional properties. To address this gap, we herein analyze and characterize the main components of MER and Mirabilis expansa starch (MES), measuring the water-absorption index (WAI), swelling power (SP), and water solubility index (WSI). We characterized the MES morphological and structural properties by using scanning electron microscopy (SEM). We also examined the starch pasting properties using a Rapid Visco Analyzer (RVA) to determine the peak viscosity (PV), final viscosity (FV), pasting temperature (PT), breakdown (BD), and setback (SB). The thermal properties were determined by differential scanning calorimetry (DSC), the crystallinity by X-ray diffraction, and the molecular structure by Fourier transform infrared spectrometry (FTIR). The main components in the MER and MES were carbohydrates and crude fiber. The MES appeared rich in amylopectin. The functional properties, the WAI, SP, and WSI, were dependent on temperature. The MES showed no morphological changes, a moderate gelatinization temperature, and C-type crystallinity. Finally, the FTIR spectrum presented the typical form for an unmodified starch. Based on these results, Mirabilis expansa may be considered a natural, non-conventional source of starch with potential applications in the food, chemical, and pharmaceutical industries. Full article

Current finger-vein or palm-vein recognition systems usually require direct contact of the subject with the apparatus. This can be problematic in environments where hygiene is of primary importance. In this work we present a contactless vascular biometrics sensor platform named sweet which can be used for hand vascular biometrics studies (wrist, palm, and finger-vein) and surface features such as palmprint. It supports several acquisition modalities such as multi-spectral Near-Infrared (NIR), RGB-color, Stereo Vision (SV) and Photometric Stereo (PS). Using this platform we collected a dataset consisting of the fingers, palm and wrist vascular data of 120 subjects. We present biometric experimental results, focusing on Finger-Vein Recognition (FVR). Finally, we discuss fusion of multiple modalities. The acquisition software, parts of the hardware design, the new FV dataset, as well as source-code for our experiments are publicly available for research purposes. Full article

As a strategic crop of dry farming in northern China, the photosynthetic characteristics and stress resistance of foxtail millet (Setaria italica L.) are crucial to yield formation. This study aimed to explore the physiological characteristics of various foxtail millet varieties and screen high-efficiency varieties adapted to semi-arid climates. In the agro-pastoral ecotone of northern Shanxi Province, the physiological and ecological parameters, etc. of six cultivars were measured. The results showed that different cultivars had bimodal diurnal photosynthetic curves with distinct peak values and midday depression degrees, reflecting varied responses to high midday temperature and light stress. Dabaigu and Jingu 21 performed superiorly, with mean daily net photosynthetic rates (Pn) of 22.99 and 20.72 µmol·m⁻²·s⁻¹, significantly higher than Jinmiao K1 (12.87 µmol·m⁻²·s⁻¹). Chlorophyll fluorescence analysis showed Dabaigu had higher potential activity (F_v/F₀) of 3.98 than Jinmiao K1 (2.40). Jingu 21 synergistically optimized plant height, stem diameter, and biomass accumulation. Dabaigu and Jingu 21 are elite cultivars for the agro-pastoral ecotone of northern Shanxi Province due to high photosynthetic efficiency, strong photoprotection, and morphological plasticity. Full article

Evaluating salt tolerance based on agro-physiological traits is resource-intensive when testing numerous genotypes under both control and saline conditions. Focusing specifically on stress conditions may streamlines the process while effectively revealing the physiological mechanisms underlying salt tolerance in genotypes. This study investigated whether control treatments are necessary for accurate salt tolerance assessment by analyzing 22 wheat genotypes under real field conditions with control and 150 mM NaCl salinity. Genotypes were grouped based on absolute trait values of ionic and agro-physiological traits under normal or salinity stress conditions separately, as well as stress tolerance indices (STIs) that consider the genotypes’ performance under stress compared to non-stress conditions. Heatmap clustering of ionic, physiological, or growth and yield traits under salinity stress successfully differentiated between salt-tolerant (Sakha 93) and sensitive (Sakha 61) genotypes. In contrast, the heatmap of ionic and physiological traits under control conditions or STIs of ionic and growth and yield traits failed to distinguish between the two genotypes. When categorized based on control-condition values or STIs, the Sakha 93 group performed similarly or worse than the Sakha 61 group. However, under salinity stress, the Sakha 93 group consistently outperformed the Sakha 61 group. Salinity-stress trait values provided significant insights into the salt tolerance mechanisms of the tested genotypes, whereas control condition data offered no meaningful contribution to understanding salinity tolerance. In summary, assessing ionic and agro-physiological traits under salinity stress alone can accurately evaluate the salt tolerance of wheat genotypes in real field conditions, eliminating the necessity of determining them under control conditions. This method not only saves effort, time, and resources when evaluating the salt tolerance of a large number of genotypes, but also offers a reliable way to understand the mechanisms of salt tolerance through agro-physiological traits. Full article

Venoms of the Palearctic vipers in the Macrovipera genus cause severe procoagulant clinical effects, yet the precise molecular targets remain incompletely defined. To fill this toxicological knowledge gap, we tested five Macrovipera venoms—M. lebetina cernovi, M. l. obtusa, M. l. turanica (Turkmenistan and Uzbekistan localities), and M. schweizeri—using plasma clotting assays, Factors VII, X, XI, and XII and prothrombin zymogen activation assays, and SDS-PAGE to visualise Factor V (FV) cleavage. All venoms induced extremely rapid clot formation (10.5–12.5 s) compared with the negative control (spontaneous clotting) of 334.6 ± 3.6 s) and the positive control (kaolin trigger) of 55.8 ± 1.9 s. Activation of FVII or FXI was negligible, whereas consistent FX activation and species-variable FXII activation, both moderate, were observed. Prothrombin remained inert in the absence of cofactors, but the presence of FV or FVa elicited potent thrombin generation. SDS-PAGE confirmed proteolytic conversion of the 330 kDa FV zymogen into the ~105 kDa heavy and ~80 kDa light chains of FVa by the venoms of all species. This data demonstrates that Macrovipera venoms rely on a dual enzyme strategy: (i) activation of FV to FVa by serine proteases and (ii) FVa-dependent prothrombin activation by metalloproteases. These results reveal that prothrombin activation is the dominant procoagulant pathway and overshadows the historically emphasised FX activation. This mechanism mirrors, yet is evolutionarily independent from, the FXa:FVa prothrombinase formation seen in Australian elapid venoms, highlighting convergent evolution of cofactor-hijacking strategies among snakes. The discovery of potent FVa-mediated prothrombin activation in Macrovipera challenges existing paradigms of viperid venom action, prompts re-evaluation of related genera (e.g., Daboia), and underpins the design of targeted antivenom and therapeutic interventions. Full article

Walnut (Juglans regia L.), an ecologically and economically important species, requires the elucidation of its salt stress response mechanisms for improved salt tolerance breeding. This study elucidates the physiological and molecular mechanisms through which exogenous methyl jasmonate (MeJA) mitigates salt stress in walnut, providing novel strategies for salt-tolerant cultivar development. This integrated study combined physiological, biochemical, and multi-omics analyses to decipher how exogenous MeJA enhances ROS scavenging through the synergistic activation of phenylalanine (Phe), tryptophan (Trp), and α-linolenic acid pathways, establishing a multilevel antioxidant defense network. MeJA treatment effectively mitigated salt stress-induced oxidative damage, as demonstrated by a significant 16.83% reduction in malondialdehyde (MDA) content, concurrent 11.60%, 10.73% and 22.25% increases in superoxide dismutase (SOD), peroxidase (POD), and catalase (CAT) activities, respectively, the elevation of osmoregulatory soluble sugars (SS), and 1.2- to 2.0-fold upregulation of key antioxidant enzyme genes (SOD, POD, APX, GPX, DHAR) and elevated osmoregulatory substances (soluble sugars, SS). Improved photosynthetic parameters (P_n, G_s) and chlorophyll fluorescence efficiency (F_v/F_m) collectively indicated reduced oxidative stress (improved by 7.97–23.71%). Joint metabolomic-transcriptomic analyses revealed MeJA-enhanced ROS scavenging via the coordinated regulation of Phe, Trp, and α-linolenic acid pathways. In summary, MeJA significantly enhanced reactive oxygen species (ROS) scavenging efficiency and comprehensive antioxidant capacity in walnut seedlings through the synergistic regulation of key metabolic pathways, effectively mitigating salt stress. These findings establish a crucial mechanistic foundation for understanding plant salt stress responses and advance the utilization of MeJA-mediated strategies for the genetic improvement of salinity tolerance in walnut. Future research should prioritize optimizing MeJA application protocols and functionally validating key regulatory genes for breeding applications. Full article

The aim of this study was to evaluate (a) the degree of conversion (DC%), (b) film thickness, and (c) the effect of film thickness on DC% in modern light-cured resin composite restoratives [Filtek Universal (F), Clearfil Majesty ES 2 Universal (M), Tetric EvoCeram (T) and Viscalor (V)] used for luting composite onlays before/after preheating. For (a), the luting composites placed at 150 μm film thickness under the onlays (4 mm thickness, 2.9% transmittance) were light-cured for 120 s (3 × 40 s top, buccal, lingual sites) before and after preheating (54 °C/5 min-F,M,T and 65 °C/30 s-V). The DC% was measured at central, middle and side locations along the median in-length axis by ATR-FTIR spectroscopy. Specimens polymerized without onlays (40 s, top) served as controls. For (b), film thickness was measured employing a modified ISO 4049 standard (37 °C plate temperature, 5 N load) before and after preheating, using a dual-cured resin luting agent as control. For (c), onlays were luted with preheated T at 150 and 350 μm film thickness and light-cured for 2 × (3 × 40) s and 3 × (3 × 40) s, employing directly irradiated specimens (60 s, 120 s) as controls. For (a), significant differences were found in F and T before and after preheating. Before preheating, significant differences were registered between F–T, F–M, F–V and V–T, whereas after they were registered between F–M, F–T and F–V. All these values were significantly lower than the controls. For (b), significantly lower film thickness was recorded after preheating (−16.1–−33.3%, highest in V), with a ranking of F, M > V > T (before) and F, M > T, V (after). All values were significantly higher than the control. For (c), increased exposure improved DC% in the greater spacer group, with the controls providing superior values. It can be concluded that the use of modern highly filled composites as luting agents for low translucency onlays may result in suboptimal polymerization and film thickness, warranting caution. Full article

Peanut cultivation is widely practiced using plastic mulch film, resulting in the accumulation of microplastics/nanoplastics (MPs/NPs) in agricultural soils, potentially negatively affecting peanut growth. To investigate the effects of two polystyrene (PS) sizes (5 μm, 50 nm) and three concentrations (0, 10, and 100 mg L⁻¹) on peanut growth, photosynthetic efficiency, and physiological characteristics, a 15-day hydroponic experiment was conducted using peanut seedlings as the experimental material. The results indicated that PS-MPs/NPs inhibited peanut growth, reduced soil and plant analyzer development (SPAD) values (6.7%), and increased levels of malondialdehyde (MDA, 22.0%), superoxide anion (O₂⁻, 3.8%) superoxide dismutase (SOD, 16.1%) and catalase (CAT, 12.1%) activity, and ascorbic acid (ASA, 12.6%) and glutathione (GSH, 9.1%) contents compared to the control. Moreover, high concentrations (100 mg L⁻¹) of PS-MPs/NPs reduced the peanut shoot fresh weight (16.1%) and SPAD value (7.2%) and increased levels of MDA (17.1%), O₂⁻ (5.6%), SOD (10.6%), POD (27.2%), CAT (7.3%), ASA (12.3%), and GSH (6.8%) compared to low concentrations (10 mg L⁻¹) of PS-MPs/NPs. Notably, under the same concentration, the impact of 50 nm PS-NPs was stronger than that of 5 μm PS-MPs. The peanut shoot fresh weight of PS-NPs was lower than that of PS-MPs by an average of 7.9%. Additionally, we found that with an increasing exposure time of PS-MPs/NPs, the inhibitory effect of low concentrations of PS-MPs/NPs on the fresh weight was decreased by 2.5%/9.9% (5 d) and then increased by 7.7%/2.7% (15 d). Conversely, high concentrations of PS-MPs/NPs consistently reduced the fresh weight. Correlation analysis revealed a clear positive correlation between peanut biomass and both the SPAD values as well as Fv/Fm, and a negative correlation with MDA, SOD, CAT, ASA, and GSH. Furthermore, the presence of PS-MPs/NPs in roots, stems, and leaves was confirmed using a confocal laser scanning microscope. The internalization of PS-MPs/NPs within peanut tissues negatively impacted peanut growth by increasing the MDA and O₂⁻ levels, reducing the SPAD values, and inhibiting the photosynthetic capacity. In conclusion, the study demonstrated that the effects of PS on peanuts were correlated with the PS size, concentration, and exposure time, highlighting the potential risk of 50 nm to 5 μm PS being absorbed by peanuts. Full article

Brown algae such as Ascophyllum nodosum (AN) and Fucus vesiculosus (FV) are gaining considerable attention as functional feed additives due to their health-beneficial properties. This study evaluated the antioxidant potential of AN and FV extracts in intestinal epithelial cells and the in vivo model Caenorhabditis elegans (C. elegans). Aqueous AN and FV extracts were characterized for total phenolic content (TPC), antioxidant capacity (TEAC, FRAP), and phlorotannin composition using LC-HRMS/MS. Antioxidant effects were assessed in vitro, measuring AAPH-induced ROS production in Caco-2 and IPEC-J2 cells via H₂DCF-DA, and in vivo, evaluating the effects of paraquat-induced oxidative stress and AN or FV treatment on worm motility, GST-4::GFP reporter expression, and gene expression in C. elegans. FV exhibited higher total phenolic content, antioxidant capacity (TEAC, FRAP), and a broader phlorotannin profile (degree of polymerization [DP] 2–9) than AN (DP 2–7), as determined by LC-HRMS/MS. Both extracts attenuated AAPH-induced oxidative stress in epithelial cells, with FV showing greater efficacy. In C. elegans, pre-treatment with AN and FV significantly mitigated a paraquat-induced motility decline by 22% and 11%, respectively, compared to PQ-stressed controls. Under unstressed conditions, both extracts enhanced nematode healthspan, with significant effects observed at 400 µg/g for AN and starting at 100 µg/g for FV. Gene expression analysis indicated that both extracts modulated antioxidant pathways in unstressed worms. Under oxidative stress, pre-treatment with AN and FV significantly reduced GST-4::GFP expression. In the nematode, AN was more protective under acute stress, whereas FV better supported physiological function in the absence of stressors. These findings demonstrate that AN and FV counteract oxidative stress in intestinal epithelial cells and in C. elegans, highlighting their potential as stress-reducing agents in animal feed. Full article

Using light-emitting diodes (LEDs), we examined how different light wavelengths influence the hypersensitive response (HR) in tobacco plants infected with Pseudomonas syringae pv. tomato (Pst). Pst-infiltrated plants exhibited greater resistance to Pst infection under green and blue light compared to white and red light, as indicated by reduced HR-associated programmed cell death, lower H₂O₂ production, and up to 64% reduction in membrane damage. During the late stage of HR, catalase and ascorbate peroxidase activities peaked under green and blue LEDs, with 5- and 10-fold increases, respectively, while superoxide dismutase activity was higher under white and red LEDs. Defense-related genes CHS1, PALa, PR1, and PR2 were more strongly induced by white and red light. The plants treated with green or blue LEDs during Pst infection prompted faster degradation of phototoxic Mg-porphyrins and exhibited smaller declines in F_v/F_m, electron transport rate, chlorophyll content, and LHCB expression compared to those treated with white or red LEDs. By contrast, the induction of the chlorophyll catabolic gene SGR was 54% and 77% lower in green and blue LEDs, respectively, compared to white LEDs. This study demonstrates that light quality differentially affects Pst-mediated HR, with green and blue light more effectively suppressing HR progression, mainly by reducing oxidative stress through enhanced antioxidative capacity and mitigation of photosynthetic impairments. Full article

Heat stress transcription factor (Hsf) families play important roles in abiotic stress responses. However, previous studies reported that HsfBs genes may play diverse roles in response to heat stress. Here, we conducted functional analysis on a woodland strawberry Class B Hsf gene, FvHsfB1a, to improve thermotolerance. The structure of FvHsfB1a contains a typical Hsf domain for DNA binding at the N-terminus, and FvHsfB1a belongs to the B1 family of Hsfs. The FvHsfB1a protein was localized in the nucleus. The FvHsfB1a gene was expressed in various strawberry tissues and highly induced by heat treatment. Under heat stress conditions, ectopic expression of FvHsfB1a in Arabidopsis improves thermotolerance, with higher germination and survival rates, a longer primary root length, higher proline and chlorophyll contents, lower malonaldehyde (MDA) and O²⁻ contents, better enzyme activities, and greater expression of heat-responsive and stress-related genes compared to WT. FvWRKY75 activates the promoter of the FvHsfB1a gene through recognizing the W-box element. Similarly, FvWRKY75-OE lines also displayed a heat-tolerant phenotype, exhibiting more proline and chlorophyll contents, lower MDA and O²⁻ contents, and higher enzyme activities under heat stress. Taken together, our study indicates that FvHsfB1a is a positive regulator of heat stress. Full article

Soil salinization severely limits plant growth and productivity. Mulberry (Morus alba L.), an economically and ecologically important tree, is widely cultivated, yet its salt-tolerance mechanisms at the seedling stage remain insufficiently understood. This study investigated the physiological and biochemical responses of two-year-old mulberry (‘Tailai Sang’) seedlings subjected to six NaCl treatments (0, 50, 100, 150, 200, and 300 mmol L⁻¹) for 28 days. Results showed that growth parameters and photosynthetic gas exchange exhibited dose-dependent declines. The reduction in net photosynthetic rate (Pn) was attributed to both stomatal limitations (decreased stomatal conductance) and non-stomatal limitations, as evidenced by a significant decrease in the maximum quantum efficiency of photosystem II (Fv/Fm) under high salinity. To cope with osmotic stress, seedlings accumulated compatible solutes, including soluble sugars, proteins, and proline. Critically, mulberry seedlings demonstrated effective ion homeostasis by sequestering Na⁺ in the roots to maintain a high K⁺/Na⁺ ratio in leaves, a mechanism that was compromised above 150 mmol L⁻¹. Concurrently, indicators of oxidative stress—malondialdehyde (MDA) and H₂O₂—rose significantly with salinity, inducing the activities of antioxidant enzymes (SOD, CAT, APX, and GR), which peaked at 150 mmol L⁻¹ before declining under extreme stress. A biomass-based LC₅₀ of 179 mmol L⁻¹ NaCl was determined. These findings elucidate that mulberry salt tolerance is a coordinated process involving three key mechanisms: osmotic adjustment, selective ion distribution, and a robust antioxidant defense system. This study establishes an indicative tolerance threshold under controlled conditions and provides a physiological basis for further field-based evaluations of ‘Tailai Sang’ mulberry for cultivation on saline soils. Full article