Search Results (1,596)

Biochar, a carbon-rich by-product of wood pyrolysis, improves soil structure, water retention, and plant growth. A two-year field experiment (2024–2025) was conducted in Poggibonsi (Tuscany, Italy) on tomato cv. “Canestrino” under contrasting climatic conditions. A single biochar application (15 t ha⁻¹) was evaluated for its effects on soil properties, water dynamics, plant water status, and ecophysiological and tissue-level responses. From the results, it emerged that biochar improved soil quality by increasing organic matter (+7.7%) and the C/N ratio (+10.6%), while reducing bulk density (1.42 to 1.25 Mg m⁻³). Soil water content was higher in amended plots, particularly in 2024 (32.84% vs. 24.87%), with a smaller increase in 2025 (24.66% vs. 24.08%). Improved soil water availability enhanced plant water status, as shown by less negative leaf water potential under stress conditions. Microscopic analyses confirmed better xylem integrity in treated plants, with reduced formation of tyloses and improved hydraulic functionality during drought. Agronomic responses reflected climatic variability: yield increased in biochar in 2024, whereas in 2025 drought stress reduced productivity in both treatments, with no significant differences. Overall, biochar improved soil moisture retention, plant water status, and ecophysiological performance, with effects dependent on seasonal rainfall patterns and environmental stress intensity. Full article

As an organic soil amendment, biochar can effectively increase the contents of soil nutrients such as nitrogen (N), phosphorus (P), and potassium (K). However, few studies have focused on the effects of biochar on K fractions and contents in maize rhizosphere soil. To investigate the effects of biochar on different K fractions in maize rhizosphere soil and on maize growth, four treatments were established in this experiment: B₀K₀ (control, no biochar and no K fertilizer), B₀K₁ (no biochar, K fertilizer at 60 kg ha⁻¹ yr⁻¹), B₁K₀ (biochar at 2.625 t ha⁻¹ yr⁻¹, no K fertilizer), and B₁K₁ (biochar at 2.625 t ha⁻¹ yr⁻¹ combined with K fertilizer at 60 kg ha⁻¹ yr⁻¹). Results indicate that biochar significantly increased microbial biomass carbon (MBC), cation exchange capacity (CEC), and electrical conductivity (EC) in the rhizosphere soil, while also improving rhizosphere soil pH. Compared with the treatment without biochar, biochar application significantly increased the content of water-soluble potassium (WSK), exchangeable potassium (EK), and non-exchangeable potassium (NEK) in the rhizosphere soil by 18.57% (2021) and 11.18% (2022), 13.49% (2021) and 11.43% (2022), 14.65% (2021) and 17.06% (2022), respectively. However, the increases in different K fractions were not accompanied by significant changes in total K (TK) content across the two years. In addition, biochar application significantly improved maize root development, plant height, stem diameter, and leaf area index. Meanwhile, aboveground dry weight and K uptake increased significantly by 13.87% (2021) and 12.04% (2022), and 41.84% (2021) and 43.87% (2022), respectively. Compared with B₀K₀, the B₁K₁ treatment—which combined biochar with K fertilizer—exhibited the highest K content in all forms within the rhizosphere soil, along with the greatest maize aboveground dry weight and K uptake. This study demonstrates biochar’s potential in meeting crop root K demands, laying the foundation for its application in enhancing soil K fertility. Full article

Highbush blueberry (Vaccinium corymbosum L.) is widely cultivated in southern Chile on acidic Andisols, where aluminum (Al³⁺) toxicity and water deficit frequently occur simultaneously and limit plant performance. However, the integrated physiological responses to these stresses and the potential protective role of methyl jasmonate (MeJA) remain poorly understood. This study evaluated the physiological, biochemical, and hormonal responses of two cultivars with contrasting resistance, Legacy (Al-resistant) and Star (Al-sensitive), exposed to Al³⁺ stress, water deficit, and their combination, with or without MeJA application. Plants were grown in Andisol soil under greenhouse conditions and subjected to eight treatments, with measurements performed at 7, 14, and 21 days. Exposure to stress conditions resulted in decreased growth, reduced leaf water status, diminished photosynthetic performance, lower pigment stability, and decreased auxin concentration as estimated by Salkowski-reactive indolic compounds. Conversely, stress conditions led to increased aluminum (Al) accumulation, elevated proline levels, enhanced lipid peroxidation, and heightened antioxidant responses. Water deficit produced the strongest reductions in photosynthesis, about 48% in Legacy and 65% in Star, whereas Al accumulated mainly in the roots of Star (14-fold). The combined stress intensified physiological limitations and oxidative damage, particularly in the Star cultivar (4-fold), which showed stronger reductions in photosynthetic parameters, higher Al accumulation, and greater lipid peroxidation. In contrast, Legacy maintained more stable physiological performance. Exogenous MeJA mitigated stress effects by reducing Al accumulation (30–35%) and oxidative damage, improving photosynthetic performance (40–60%) and water status, and partially restoring auxin levels and growth in both cultivars, being more evident in the resistant cultivar Legacy. These results indicate that MeJA contributes to the regulation of physiological and antioxidant responses associated with resistance to combined Al toxicity and water deficit in highbush blueberry. Full article

A comprehensive multiregional characterization of the spectral response of cassava leaves across different ontogenetic stages was performed. For this, ultraviolet (UV), visible (VIS) and shortwave near-infrared (UV-VIS-NIR; 200–900 nm) regions were used to identify spectral signatures and indices for their potential use as biomarkers of leaf development and physiological status of plants under induced senescence conditions. Manihot esculenta Crantz (HMC-1 variety) was used as a model. Spectral signatures were obtained from leaves at two phenological stages (4 and 6 months after planting) using UV-VIS-NIR spectroscopy by the diffuse reflectance technique. Classical and experimental spectral indices were evaluated, and their discriminatory power through different ontogenies was assessed using ANOVA/Kruskal–Wallis and post hoc tests. Senescence effects were further examined by postharvest monitoring (1–20 days), with temporal, ontogenetic, and interaction effects validated using linear mixed models (LMMs), while multivariate structure and spectral convergence were explored via principal component analysis and hierarchical clustering (PCA-HCA). Functionally Enhanced Derivative Spectroscopy (FEDS), comparative analysis, and spectral correlation mapping allowed signal’s selective enhancement and the identification of phenolic compounds, photosynthetic pigments, and structural molecular components. Results showed high ontogenetic stability of UV-associated phenolic signals (~210–220 nm), whereas the VIS region (420–600 nm) clearly differentiated young leaves. The NIR region was stable across ontogeny but highly sensitive to temporal degradation, reflecting changes in water status and internal structure. UV-VIS-NIR indices effectively differentiated young leaves and changes by stress. It is concluded that multiregional characterization of the spectral response supported by FEDS allows the extraction of robust indices with strong potential as biomarkers of leaf maturation and senescence in cassava. Full article

Rhizoctonia solani is a necrotrophic phytopathogenic fungus that causes disease in various crops. In agriculture, many crops suffer from root or seedling rot caused by this soil-borne pathogen, whereas cabbage and rice develop lesion-like symptoms on aboveground tissues. Diseases caused by R. solani are generally controlled using chemical fungicides; however, environmentally friendly alternatives are needed for sustainable agriculture. In this study, we evaluated the efficacy of lecithin, a mixture of phospholipids previously registered in Japan as an agrochemical for controlling cucumber powdery mildew, against Rhizoctonia diseases. In cabbage, foliar spraying of 0.2–1.0% soybean lecithin effectively suppressed leaf symptoms caused by R. solani isolate RhiCa-2, which was identified as AG-1 IB. In rice and Brachypodium distachyon, 0.2–1.0% lecithin significantly suppressed leaf symptoms induced by R. solani AG-1 IA. Hyphal staining of inoculated leaves revealed reduced hyphal density on lecithin-treated leaves. Consistently, hyphal growth of R. solani on cellophane placed on water agar was retarded by lecithin treatment. However, 5.0% lecithin induced phytotoxicity in B. distachyon. Egg yolk-derived lecithin also exhibited disease-suppressive activity in cabbage and B. distachyon, with efficacy comparable to that of soybean lecithin under the conditions tested. These results suggest that lecithin suppresses foliar infection by R. solani, at least in part, through direct inhibitory effects on fungal hyphae, and may serve as a potential alternative material for disease control in sustainable crop production. Full article

In rocky mountainous regions characterized by shallow, barren soils and water scarcity, non-rainfall water, such as condensation, plays a crucial ecological role in mitigating seasonal drought in forest trees. To enhance the water-use capacity of vegetation, this study utilized a previously developed eco-friendly PVA–CS/SA–Ca²⁺ hydrogel. The primary objective was to elucidate the synergistic mechanisms by which the hydrogel optimizes condensed water utilization and drives the ecophysiological recovery of Pinus tabuliformis and Platycladus orientalis, two keystone afforestation species in northern China. Utilizing a controlled environmental chamber to simulate the condensation and humidification process, the experiment established three treatments: a control group (CK), a pot-sealed group (PS, to isolate soil water absorption), and a hydrogel-amended group (Hydrogel-Root Wrapping, HRW). To comprehensively evaluate the water utilization mechanisms, the amount of condensed water captured by the system was quantified, and hydrogen isotope tracing techniques were employed to precisely track water transport pathways and contribution rates. Concurrently, key physiological parameters were systematically determined, including leaf water potential, stomatal conductance, leaf water content, net photosynthetic rate, and transpiration rate. The results demonstrated the following: (1) the hydrogel significantly enhanced the condensation water capture capacity of the system. The net mass gains of the Pinus tabuliformis and Platycladus orientalis systems under the HRW treatment reached 26.3 g and 32.9 g, respectively, which represented 1.17 and 1.30 times those of the CK treatment, and 1.52 and 1.54 times those of the PS treatment. (2) Isotope tracing confirmed that both tree species possess significant Foliar Water Uptake (FWU) capacity. Following condensation, the δ²H values in the leaves of Platycladus orientalis and Pinus tabuliformis surged to 113.5‰ and 85.3‰, respectively, with stem δ²H values increasing by 31‰ and 22‰ compared to their initial baseline. (3) The introduction of the hydrogel in the HRW treatment provided 11.2% and 10.9% of the stem water supply for Platycladus orientalis and Pinus tabuliformis, respectively, thereby reducing their dependence on soil water by 8.3% and 13.1%. In contrast, there was no significant difference in the fractional contribution of condensation water to stem water between the PS and CK treatments. (4) Regarding physiological responses, the application of the hydrogel material effectively improved the physiological status of the plants. The leaf water potentials of Pinus tabuliformis and Platycladus orientalis increased to −0.15 MPa and −1.32 MPa, respectively. Concurrently, stomatal conductance (3.25 and 3.64 mm·s⁻¹) and leaf water content (58.4% and 67.4%) were significantly higher than those in the other treatments. In summary, the hydrogel can significantly enhance the capture, conversion, and utilization efficiency of condensation water by vegetation, effectively optimizing the water supply dynamics of the system. This provides key theoretical and technical support for ecological afforestation in difficult sites within rocky mountainous areas. Full article

Sweet basil (Ocimum basilicum L.) is a member of the Lamiaceae family, which includes a wide variety of medicinal and aromatic herbs cultivated for their essential oils and bioactive compounds. However, prolonged drought stress can significantly impair growth and essential oil content. In this study, a two-season pot experiment was conducted under open-field conditions. The study was carried out at the Floricultural Nursery, Faculty of Agriculture and Natural Resources, Aswan University, Egypt, during 2024 and 2025, with the aim of assessing how foliar applications of silicon (Si) and zinc (Zn) impact the morphological, physiological, and biochemical responses of sweet basil under different soil water capacity (SWC) levels (80%, 60%, and 40% SWC). Drought stress markedly reduced plant height, branch number, leaf area, biomass, photosynthetic pigments, macronutrient content, and essential oil content, while increasing levels of proline and secondary metabolites such as phenolics, flavonoids, and ascorbic acid. Growth and productivity were highest under 80% SWC, followed by 60%, and lowest under 40%. Under drought stress (40% SWC), Si₂₀₀ increased plant dry biomass by approximately 12%, chlorophyll content by 53%, and essential oil content by 46% compared with untreated plants. Silicon application proved more effective at ameliorating the negative consequences of drought than Zn, with Si₂₀₀ combined with 80% SWC yielding the best results in terms of plant performance and essential oil percentage and content. Meanwhile, Si₂₀₀ under 40% SWC induced the highest accumulation of secondary metabolites. These results highlight the potential of silicon foliar application as a practical strategy to reduce drought stress in sweet basil, enhancing both yield and phytochemical quality, and offering valuable guidance for sustainable cultivation under water-limited conditions. Full article

Pathogenesis-related 1 (PR1) proteins are important components of plant defense and stress responses and also serve as precursors of CAP-derived peptides (CAPE), a class of small bioactive peptides involved in immune and stress signaling. Despite their potential biological significance, CAPE-producing PR1 genes have not been systematically characterized in tobacco (Nicotiana tabacum). In this study, a genome-wide analysis identified 17 CAPE-producing PR1 genes, designated NtCAPE1 to NtCAPE17, in the tobacco genome. These genes encode proteins containing conserved CAP domains and N-terminal signal peptides, with predicted hydrophilic properties and mainly vacuolar localization, indicating conserved structural features within the family. Phylogenetic analysis, gene structure organization, conserved motif profiling, chromosomal distribution, and synteny analyses revealed both evolutionary conservation and duplication-driven diversification of the NtCAPE family. Promoter cis-element analysis showed enrichment of regulatory elements associated with phytohormone signaling, development, and stress responses. Public transcriptomic datasets revealed dynamic and gene-specific expression patterns under water-deficit and salinity stress, and qRT-PCR analysis further confirmed the stress-responsive expression of selected NtCAPE genes. Functional assays using synthetic mature peptides showed that NtCAPE9 and NtCAPE17 alleviated salinity stress- and osmotic stress-induced leaf yellowing, improved chlorophyll retention, suppressed senescence-associated responses, reduced H₂O₂ accumulation and POD activity, modulated stress-responsive gene expression, and promoted seed germination under salinity and osmotic stress, respectively. These results provide a comprehensive characterization of CAPE-producing PR1 genes in tobacco and identify NtCAPE9 and NtCAPE17 as candidate stress-associated peptides with exogenous activity under salinity and osmotic stress conditions. Full article

Subcritical water extraction (SWE) is an eco-friendly and efficient technique for isolating bioactive ingredients from natural products. To improve the extraction yield of Artemisia argyi leaf polysaccharides (AAPs), a three-stage hybrid optimization strategy combining single-factor experiments, response surface methodology (RSM), neural network (NN), and direct search algorithm (DSA) was proposed. Single-factor experiments were used to screen key parameters. A Box–Behnken design (BBD)-based RSM was applied for preliminary optimization. A {3, 5, 1} structured NN was trained using 63 datasets from RSM, and DSA was used to determine the globally optimal process parameters. The optimal conditions were obtained as follows: extraction time 17.72 min, liquid-to-solid ratio 92.83 mL/g, extraction temperature 123.35 °C, stirring speed 1800 r/min, and natural pH. Under these conditions, the experimental AAP extraction yield reached 6.99%, with a relative error of only 1.16% compared with the predicted value of 6.91%. Fourier transform infrared (FT-IR) spectroscopy confirmed that the product exhibited typical polysaccharide structural characteristics. The integrated RSM–NN–DSA framework provides a reliable and high-precision approach for optimizing SWE of plant polysaccharides, showing good potential for industrial applications. Full article

To reveal the variation patterns and differences in the adaptation strategies of leaf functional traits between male and female Populus euphratica in an arid desert environment, this study evaluated the effects of sex, developmental stage, and their interaction on 31 leaf traits using variance partitioning and trait network analysis. Furthermore, we analyzed the topological characteristics of the trait networks across two dimensions: developmental stage and vertical canopy gradient. The results indicated that sex moderately explained the variation in leaf nutrient characteristics (N and K) and physiological resistance indicators (Pro). Meanwhile, developmental stage largely accounted for variations in traits such as leaf dry weight, leaf width, specific leaf area, and photosynthetic physiology. The interaction between sex and developmental stage significantly influenced leaf anatomical structures and water-use strategies. Leaf trait network analysis revealed that during development, the male network exhibited higher connectivity and shorter average path lengths, with its core traits shifting from photosynthetic physiological indicators to nutrient and water transport characteristics; female plants exhibited higher network modularity during key developmental stages, with core nodes concentrated on leaf area, biomass, and structural traits. Along the vertical canopy gradient, the male leaf trait network showed pronounced topological reorganization in the mid-to-upper layers, suggesting a stronger capacity to respond to environmental fluctuations. Conversely, the core hubs of the female leaf trait network shifted from morphogenesis toward a synergy between structure and metabolism, which may be associated with maintaining system stability at different canopy heights. These findings suggest that female and male P. euphratica may adopt “conservative” and “acquisitive” ecological adaptation strategies, respectively, potentially leading to differentiated patterns of trait variation and coordination. This study provides a theoretical basis for understanding the potential ecological adaptation mechanisms and evolutionary strategies underlying sexual dimorphism in desert plants. Full article

Diospyros comorensis Hiern is a medicinal plant traditionally utilized in the management of cardiovascular disorders. Despite its common use, the pharmacological properties and phytochemical composition remain unexplored. This study aimed to evaluate the vasorelaxant, diuretic, and antioxidant activities, as well as toxicity and phytochemical profiling, of a methanol–water extract of D. comorensis leaves (MDCR) and a decoction of D. comorensis leaf (DDCR) extract. The main phytochemicals were quantified using High-Performance Liquid Chromatography (HPLC). Antioxidant capacity was assessed using DPPH and FRAP assays. The vasorelaxant effect was evaluated in vitro on phenylephrine-precontracted aortic rings. Diuretic activity was determined by measuring Wistar rats’ urine output and electrolyte levels (Na⁺, Cl⁻, and K⁺). Toxicity was assessed using Swiss mice. The extracts showed a total phenolic content (TPC) of 29,693.02 ± 3493.75 mg GAE/100 g DW (Folin–Ciocalteu method), which was markedly higher than the total phenolics quantified by HPLC (3743.12 ± 457.32 mg/100 g DW, representing 76.38% of the total bioactive fraction). Among the quantified constituents, ellagic acid (56.36%) was the main compound. Both extracts exhibited marked antioxidant capacity along with significant vasorelaxant effects on phenylephrine-precontracted rat aorta rings, with EC50 values of 3.83 ± 0.81 µg/mL for MDCR and 4.87 ± 0.79 µg/mL for DDCR. Acute toxicity was not observed with either extract. The identified compounds may be involved in the observed antioxidant and pharmacological effects. These results show experimental evidence useful to support the traditional use of D. comorensis leaves in managing high blood pressure and highlight the antihypertensive potential of this Comorian endemic species. Further studies are necessary to characterize the biological mechanisms involved and relative bioactive substances. Reporting the pharmacological activities of D. comorensis may contribute to the sustainable use of natural resources in the Comoros Islands and Madagascar. Full article

Plant polyphenols possess various biological activities such as antioxidant and antidiabetic activities. Based on the high plant biodiversity in Thailand, selected edible plants were therefore investigated to explore how dietary polyphenols and α-glucosidase-inhibitory activity can contribute to significant control and prevention of type 2 diabetes mellitus (T2DM). Network pharmacology of antidiabetic activity was employed to predict the underlying antidiabetic mechanisms of the phytochemicals identified in the 15 selected edible Thai plants. The results showed that wild guava (Careya arborea Roxb.; CaA) leaf extract presented the highest total phenolic content (TPC). CaA exhibited the highest antioxidant activities in all the assays as a function of its TPC. Moreover, CaA showed the highest inhibitory effect on α-glucosidase activity in the test, with an IC₅₀ of 0.13 µg/mL, being approximately 1600 times more potent than the standard α-glucosidase-inhibitory drug acarbose. Phenolic profile analysis revealed that the CaA leaf extract consisted of gallic acid, caffeic acid, sinapic acid, rutin, and quercetin. The phytochemical contents of CaA strongly contributed to its antioxidant and α-glucosidase-inhibitory activity. In addition to other phytochemicals, the highest contents of the indolamine compounds tryptophan and melatonin were found in malabar spinach (Basella alba L.; BA) and water clover (Marsilea crenata C. Presl; MaC), at 2213.05 and 99.17 ng/g DW, respectively. Network pharmacology on antidiabetic activity exhibited the most relevant pathway involved in the insulin resistance and AGE-RAGE signaling pathways that caused glucose and glycogen synthesis in skeletal muscle, increasing hepatic gluconeogenesis, and reduced glycogen synthesis in the liver. The implication of these findings is that these Thai edible plants have the potential to combat diabetes by inhibiting the function of α-glucosidase. Full article

Drought stress is one of the most severe constraints affecting wheat production worldwide. Under these conditions, the development of sustainable and economically viable strategies, such as seed priming, is essential to improve wheat performance and drought resilience. The present study carried out a greenhouse experiment on four Mediterranean durum wheat cultivars (Triticum turgidum ssp. durum Desf), i.e., Karim (Kr) and Khiar (Kh) from Tunisia and Espelta (Esp) and Mocho (Mo) from Spain, subjected to drought stress conditions, and using primed abscisic acid (ABA), indole-3-acetic acid (IAA), melatonin (Mlt), and salicylic acid (SA), and non-primed seeds. In order to assess the physio-biochemical responses of durum wheat, such as plant growth, chlorophyll, relative water content (RWC), water potential (Ψw), osmotic potential (Ψs), proline, soluble sugars, starch, glycine betaine, hydrogen peroxide, malondialdehyde, and antioxidant enzyme activities. The results showed that water stress significantly reduced plant growth, SPAD index, RWC, Ψw, and Ψs, while upregulating H₂O₂ and MDA levels, depending on the wheat cultivars. Soluble sugars decreased, whereas starch, glycine betaine, and proline accumulated in all cultivars. Superoxide dismutase activity was reduced (24–37%) under water stress as compared to the control condition, while APX, CAT, and POD activities significantly increased. Among the cultivars, Esp exhibited the greatest plasticity in response to water deficit, whereas Kh appeared to be most sensitive. Furthermore, the present results revealed that the priming durum wheat seeds with ABA, IAA, Mlt, and SA improved leaf hydration, particularly through soluble sugar accumulation. Seed priming also alleviated oxidative stress by reducing H₂O₂ and MDA levels and stimulating APX, CAT, POD, and SOD activities. Plants grown from non-primed seeds of Spanish and Tunisian cultivars exhibited differential responses to drought stress, and those derived from primed seeds showed varying degrees of enhanced drought tolerance. Espelta demonstrated a high potential for stress tolerance and responsiveness to priming, followed by Karim, whereas Khiar was the most sensitive cultivar. Overall, the cultivars can be ranked in decreasing order of stress tolerance as Esp > Kr > Mo > Kh. These findings highlight the potential of phytohormone-based seed priming as an efficient and practical approach to enhance drought resilience in durum wheat, offering promising prospects for improving crop performance and stability under increasingly water-limited conditions in the era of climate change. Full article

Urbanization significantly alters microclimatic and environmental conditions, thereby affecting the physiological functioning of urban trees. This study aimed to evaluate whether leaf-level physiological measurements and satellite-based remote sensing indicators consistently detect similar physiological response patterns across contrasting urban and park environments in Novi Sad, Serbia, using three tree species (Platanus × acerifolia, Celtis australis, and Tilia tomentosa). Leaf gas exchange parameters, including stomatal conductance (g_s), net photosynthesis (A), transpiration rate (E), water use efficiency (WUE), and intercellular CO₂ concentration (Ci), were measured using a CIRAS-3 portable photosynthesis system. Satellite-derived variables included vegetation indices (NDVI, NDRE, NDMI) and land surface temperature (LST), which were used to construct proxy indicators of physiological processes. Results revealed consistent differences between urban and park environments, with urban conditions associated with reduced photosynthetic activity, stomatal conductance, and transpiration, alongside increased physiological stress. These patterns were consistently captured by satellite-derived proxies, demonstrating strong agreement in the direction of physiological responses across species and environments. Species-specific responses were evident, with P. × acerifolia showing the highest sensitivity to urban conditions, C. australis exhibiting intermediate responses, and T. tomentosa suggesting comparatively greater tolerance. The integration of leaf-level measurements with satellite-derived proxies provides a robust framework for scaling physiological processes and monitoring urban tree performance, highlighting the potential of remote sensing for assessing urban vegetation stress and supporting evidence-based urban forestry management. Full article