Search Results (110)

Flavonoids serve as crucial plant antioxidants in drought tolerance, yet their antioxidant regulatory mechanisms within mycorrhizal plants remain unclear. In this study, using a two-factor design, trifoliate orange (Poncirus trifoliata (L.) Raf.) seedlings in the four-to-five-leaf stage were either inoculated with Funneliformis mosseae or not, and subjected to well-watered (70–75% of field maximum water-holding capacity) or drought stress (50–55% field maximum water-holding capacity) conditions for 10 weeks. Plant growth performance, photosynthetic physiology, leaf flavonoid content and their antioxidant capacity, reactive oxygen species levels, and activities and gene expression of key flavonoid biosynthesis enzymes were analyzed. Although drought stress significantly reduced root colonization and soil hyphal length, inoculation with F. mosseae consistently enhanced the biomass of leaves, stems, and roots, as well as root surface area and diameter, irrespective of soil moisture. Despite drought suppressing photosynthesis in mycorrhizal plants, F. mosseae substantially improved photosynthetic capacity (measured via gas exchange) and optimized photochemical efficiency (assessed by chlorophyll fluorescence) while reducing non-photochemical quenching (heat dissipation). Inoculation with F. mosseae elevated the total flavonoid content in leaves by 46.67% (well-watered) and 14.04% (drought), accompanied by significantly enhanced activities of key synthases such as phenylalanine ammonia-lyase (PAL), chalcone synthase (CHS), chalcone isomerase (CHI), 4-coumarate:coA ligase (4CL), and cinnamate 4-hydroxylase (C4H), with increases ranging from 16.90 to 117.42% under drought. Quantitative real-time PCR revealed that both mycorrhization and drought upregulated the expression of PtPAL1, PtCHI, and Pt4CL genes, with soil moisture critically modulating mycorrhizal regulatory effects. In vitro assays showed that flavonoid extracts scavenged radicals at rates of 30.07–41.60% in hydroxyl radical (•OH), 71.89–78.06% in superoxide radical anion (O₂^•−), and 49.97–74.75% in 2,2-diphenyl-1-picrylhydrazyl (DPPH). Mycorrhizal symbiosis enhanced the antioxidant capacity of flavonoids, resulting in higher scavenging rates of •OH (19.07%), O₂^•− (5.00%), and DPPH (31.81%) under drought. Inoculated plants displayed reduced hydrogen peroxide (19.77%), O₂^•− (23.90%), and malondialdehyde (17.36%) levels. This study concludes that mycorrhizae promote the level of total flavonoids in trifoliate orange by accelerating the flavonoid biosynthesis pathway, hence reducing oxidative damage under drought. Full article

Activated carbon prepared from coconut shell was characterized using SEM/EDS, N₂-sorption, XRD analysis, Raman, and FTIR spectroscopy. It was then evaluated in terms of its capacity to adsorb nitrobenzene, a priority pollutant, from water samples with varying pH levels. Initial studies revealed high adsorption capacity; further studies were broadened to include nitrobenzene derivative, dinitrobenzene, as real samples are expected to contain a mixture of these pollutants. The maximum amount of adsorbed adsorbate increased notably with temperature, reaching 12.88 mg g⁻¹ and 42.75 mg g⁻¹ for nitrobenzene and dinitrobenzene, respectively, at 35 °C. Thermodynamic considerations and determined values of ∆G⁰ and ∆S⁰ indicated that the adsorption process of both nitrobenzene and dinitrobenzene is spontaneous and ∆H⁰ value indicated that it is endothermic in the studied temperature range. A study of the simultaneous adsorption of nitrobenzene and dinitrobenzene indicated a higher affinity toward dinitrobenzene. This study pointed out that coconut shell-derived activated carbon holds high potential as an adsorbent for removing nitrobenzene and its derivatives from water samples. Full article

Drought stress is a crucial factor limiting plant survival and growth, especially during the seedling establishment stage. A deep understanding of different plants’ responses to drought stress and their drought resistance is of great significance for vegetation restoration under drought conditions. This study selected one-year-old seedlings of Winter Jasmine (Jasminum nudiflorum), Oleander (Nerium oleander), Privet (Ligustrum lucidum), and Redleaf Photinia (Photinia × fraseri) as research objects. Through pot experiments, we investigated the physiological and biochemical responses of these shrubs under different levels of drought stress (control, mild, moderate, and severe drought stress, corresponding to 75%, 60%, 45%, and 30% of field maximum water holding capacity) to comprehensively assess their drought resistance capabilities. The research results indicated that as the level of drought stress increased, significant changes (p < 0.05) occurred in the physiological and biochemical indicators of all four plant species. The chlorophyll content (Chla+b) of Winter Jasmine and Redleaf Photinia gradually decreased with the intensification of stress, while the Chla+b of Oleander showed the most significant decline under moderate stress and Privet was most affected under mild stress. The proline (Pro) and soluble sugar (SS) contents of all four plants exhibited an upward trend, suggesting that the plants coped with drought stress by accumulating these osmoregulatory substances. Drought stress led to damage to plant cell membranes, manifested by an increase in malondialdehyde content (MDA), with Winter Jasmine showing the most pronounced increase. The activities of peroxidase (POD) and superoxide dismutase (SOD) in the four plant species responded differently to drought stress: the POD activity of Oleander and Redleaf Photinia increased with the deepening of stress, while that of Winter Jasmine and Privet decreased. A comprehensive evaluation of the drought tolerance of the four plant species was performed using principal component analysis and affiliation function value methods. The drought tolerance of the four shrubs, from strongest to weakest, was as follows: Redleaf Photinia > Oleander > Privet > Winter Jasmine. This finding provides valuable insights for plant selection in ecological slope protection projects, and Redleaf Photinia and Oleander can be promoted for use in vegetation restoration work under drought conditions. Full article

To clarify the response mechanisms of soil nematodes as bioindicators of ecosystem health to precipitation variations in loess hilly forests, this study investigated soil nematodes in pure Populus hopeiensis forests across different precipitation gradients in Wuqi County. Through soil physicochemical analysis and high-throughput sequencing of soil nematodes, we analyzed the characteristics of soil nematode communities and their responses to precipitation variation. The results demonstrated the following: (1) Dominant genera and trophic groups of soil nematodes were significantly influenced by precipitation, with Acrobeloides prevailing across all gradients while Paratylenchus reached maximum abundance (26.8%) in moderate precipitation zones. (2) Bacterivorous nematodes prevailed in both low- and high-precipitation zones, while herbivorous nematodes constituted the highest proportion in moderate precipitation zones. The abundances of herbivorous and fungivorous nematodes exhibited an initial increase followed by a decrease with rising precipitation, whereas predatory–omnivorous nematodes displayed the opposite trend. (3) The Chao1 and Shannon indices of soil nematodes initially increased and then decreased with increasing precipitation, reaching a peak in the Jinfoping site. Moreover, there were significant differences in nematode community structure among different precipitation gradients. (4) Redundancy analysis and PLS-PM modeling identified soil water content (SWC), total nitrogen (TN), and capillary water holding capacity (CWHC) as key drivers of nematode communities. Precipitation indirectly regulated nematode functionality by modifying soil physicochemical properties and microbial activity. (5) Ecological function analysis revealed bacterial-dominated organic matter decomposition (Nematode Channel Ratio, NCR > 0.75) in the Changcheng and Baibao sites, contrasting with fungal channel predominance (NCR < 0.75) in Jinfoping. This research elucidates the mechanism whereby precipitation drives nematode community divergence through regulating soil physicochemical properties and microbial activity. The findings provide scientific basis for soil biodiversity conservation and ecological restoration benefit assessment in regional ecological restoration projects, and soil health management and sustainable land use in agricultural ecosystems. Full article

This study aimed to provide systematic insight into the relationship between spray conditions and the physicochemical and gelation properties of egg white protein (EWP). Specifically, the effects of two key factors, the inlet temperature and flow rate, on the physicochemical and structural properties of EWP were determined. The analysis revealed that as the spray-drying temperature increased, more hydrophobic groups in EWP were exposed and prone to aggregate. Furthermore, the physicochemical and rheological properties and microstructure of egg white protein gel (EWPG) were determined. The results indicate that under a relatively high inlet temperature and a low flow rate, the hardness, springing, and water-holding capacity of the produced gel were improved. Excessively high temperatures were detrimental to pre-aggregate formation and the development of a homogeneous network. The rheological results demonstrate that the EWPG exhibited a weak frequency dependence and elastic-dominant gel characteristics. Further analysis indicated that the inlet temperature significantly influenced the nonlinear response of the EWPG, with the strongest higher-order viscous nonlinear properties observed at 140 °C. The microstructure suggested that at 140 °C, the EWPG achieved a minimum porosity of 50.07% and a maximum fractal dimension (D_f) of 2.745, where a uniform network structure was generated. This study demonstrated that relatively high temperatures and low flow rates in the spray-drying process were advantageous for producing egg white protein gel with desirable characteristics, which has potential for the actual application of egg-based food products. Full article

A facile method was employed to impregnate activated carbon, a commonly used water treatment medium, with nanostructured magnesium oxide for fluoride removal. Batch adsorption tests were conducted to evaluate the adsorption performance of the nanostructured magnesia-impregnated activated carbon (nMgO@AC) for fluoride removal. The results demonstrated that this composite material exhibited a good adsorption capacity, with a maximum equilibrium uptake of approximately 121.1 mg/g for fluoride. Kinetic studies revealed that the adsorption process followed the pseudo-second-order adsorption kinetic model, reaching equilibrium in about 100 min. Within the initial pH range of 3 to 11, the adsorption efficiency of nMgO@AC for fluoride remained above 95%, indicating that the initial solution pH had a minimal effect on the material’s fluoride removal capability. The adsorption mechanism was elucidated by characterizing the material properties before and after adsorption using SEM, TEM, XRD and XPS. Initially, magnesium oxide reacted with water and rapidly transformed into magnesium hydroxide. Subsequently, a ligand exchange occurred between the hydroxide groups in magnesium hydroxide and fluoride ions in the aqueous solution, resulting in the effective removal of fluoride. The findings of this study suggest that nanostructured magnesia-impregnated activated carbon holds significant potential for the treatment of fluoride-containing wastewater, particularly for highly alkaline wastewater. Full article

Magnoliaceae plants have high ornamental value, resulting in their widespread use in landscaping construction, and play a major role in the ecological functions of soil and water conservation. However, the landscape value of magnolias from the perspective of the water conservation capacity of the litter and soil layers is not yet fully understood; this restricts the popularization and application of Magnoliaceae plants in landscaping. In this study, we determined the characteristics of the litter thickness and mass, water absorption process, and soil water-holding capacity associated with five Magnoliaceae plants (Michelia shiluensis, M. crassipes, M. foveolata, M. maudiae, and M. odora). (1) The total litter thickness ranged from 2.29 to 5.58 cm, with M. crassipes achieving the highest value. The total litter mass for M. shiluensis (25.11 ± 2.58 t·ha⁻¹) was largely greater than that for the other magnolias. The mass of the un-decomposed litter (UL) layer was 1.31- to 3.82-fold larger than that of the semi-decomposed litter (SL). (2) The maximum water retention capacity (H_max) and effective water retention capacity (H_eff) of M. shiluensis were markedly larger than those of the other magnolias. (3) The W_max and W_eff of the UL layer were greater than those of the SL layer. (4) The soil bulk density varied from approximately 1.22 ± 0.08 g·cm⁻³ to 1.55 ± 0.08 g·cm⁻³, and the total soil porosity varied from 40.03 ± 3.44% to 46.42 ± 1.02%. The soil bulk density rose with an increasing soil depth, yet the total porosity was reduced. The soil water-holding capacity of the 0–30 cm soil layer varied from approximately 26.23 to 70.33 t·ha⁻¹, with soil near M. crassipes having the greatest water-holding capacity. The soil water infiltration recorded for M. crassipes was significantly higher than that of the other magnolias. The water conservation capacities associated with M. crassipes and M. shiluensis were the largest, which may suggest that these species are better at increasing rainfall interception, lightening splash erosion, and reducing surface runoff. Hence, we suggest that M. crassipes and M. shiluensis should be prioritized in landscaping applications. Full article

The use of water-efficient soil amendments has gained increasing importance in agriculture, particularly in regions facing water scarcity. So, this study evaluates the impact of silica and nano-silica hydrogels on soil water retention, crop yield, and crop water productivity under variable irrigation regimes. Using a randomized complete block design with furrow irrigation, the experiment tested different hydrogel application rates and irrigation levels in rice (Oryza sativa L.) and clover (Trifolium alexandrinum L.) across two growing seasons. Statistical tests, including ANOVA and t-tests, confirm that nano-silica hydrogel significantly improves soil properties, yield, and crop water productivity (CWP), especially at moderate irrigation levels (70–90% of water requirements). In the first season, nano-silica hydrogel enhanced rice yield, with a maximum yield of 10.76 tons ha⁻¹ with 90% irrigation and 119 kg ha⁻¹ of hydrogel compared with other treatments. In the second season, clover yields were also positively affected, with the highest fresh forage yield of 5.02 tons ha⁻¹ with 90% irrigation and 119 kg ha⁻¹ nano-silica hydrogel. Despite seasonal variation, nano-silica hydrogel consistently outperformed silica hydrogel in terms of improving soil water retention, reducing bulk density, and enhancing hydraulic conductivity across different irrigation levels. Principal Component Analysis (PCA) revealed that nano-silica hydrogel significantly improved soil water retention properties, including the water-holding capacity (WHC), field capacity (FC), and available water (AW), and reduced the wilting point (WP). These improvements, in turn, led to increased crop yield and water productivity, particularly at moderate irrigation levels (70–90% of the crop’s total water requirements. These findings highlight the potential of nano-silica hydrogel as an effective amendment for improving soil water retention, enhancing crop productivity, and increasing crop water productivity under reduced irrigation conditions. Full article

In the context of increasing water scarcity and environmental pollution, this study investigates the synthesis and application of p(AA-Oco-AAm)-g-Citrus Sinensis Peel hydrogel (CSP hydrogel) to enhance soil water retention and remove organic dyes from wastewater. Hydrogels were prepared using a combination of acrylamide and acrylic acid, with the incorporation of citrus peel as a natural resource. The water absorption capacity of the hydrogels was evaluated, achieving a maximum retention rate of 477 g/g, significantly improving the water-holding ability of various soil types. Additionally, the hydrogels demonstrated a strong affinity for methylene blue, with an equilibrium adsorption capacity reaching 2299.45 mg/g, indicating their effectiveness in wastewater treatment. Kinetic and isothermal adsorption models were applied to analyze the adsorption dynamics, revealing a superior fit to the Langmuir model. The hydrogels maintained structural integrity and reusability over multiple cycles, underscoring their potential for sustainable agricultural practices and environmental remediation. This research highlights the dual benefits of utilizing agricultural waste for the development of eco-friendly materials while addressing critical challenges in water management and pollution control. Full article

The purpose of this research was to investigate the characteristics of different plant-based sources rich in protein, chickpea flour (CPF), hazelnut oil cake (HOC), soy protein isolate (SPI) and concentrate (SPC), and pea protein isolate (PPI) for their subsequent use in the manufacture of meat analogs. The protein sources were analyzed for dry matter, ash, protein, fat, starch, dietary fiber, water holding capacity, granulosity, color parameters (L*, a*, b*, C*, YI), antioxidant activity before and after gastrointestinal in vitro digestion, and amino acid and mineral compositions. The highest dry matter content was determined in hazelnut oil cake and pea protein isolate. For the protein content, maximum values were obtained for the protein isolate and concentrate samples, from 52.80% to 80.50%, followed by hazelnut oil cake and chickpea flour. The water-holding capacity of all plant sources was directly influenced by the values of protein content, dietary fiber, and granulosity. The results obtained after gastrointestinal digestion also showed quite significant antioxidant activity, which is due to the process of hydrolysis and denaturation of plant-based protein sources in the gastrointestinal tract. Major amino acids identified in the analyzed samples were glutamic acid, leucine, arginine, phenylalanine, serine, valine, alanine, and tyrosine from minerals P, Na, Mg, and Ca. Principal component analysis (PCA) was used to illustrate the relationship between physicochemical characteristics, amino acid composition, mineral composition, and antioxidant activity determined in the plant-based materials. Full article

This study explores the optimisation of rearing substrates for black soldier fly larvae (BSFL). First, the ideal dry matter content of substrates was determined, comparing the standard 30% dry matter (DM) with substrates hydrated to their maximum water holding capacity (WHC). Substrates at maximal WHC yielded significantly higher larval survival rates (p = 0.0006). Consequently, the WHC approach was adopted for further experiments. Using these hydrated artificial substrates, fractional factorial designs based on central composite and Box–Behnken designs were employed to assess the impact of macronutrient composition on bioconversion efficiency. The results demonstrated significant main, interaction, and quadratic effects on bioconversion efficiency. Validation with real-life substrates of varied protein content, including indigestible feather meal, affirmed the predictive model’s accuracy after accounting for protein source digestibility. This research underscores the importance of optimal hydration and macronutrient composition in enhancing BSFL growth and bioconversion efficiency. Full article

This study assessed the technological potential and bioactive compounds present in purple yampee (Dioscorea trifida L.f.) lyophilized powder, peeled and whole flour, as well as the tuber peel, starch residual fiber, and wastewater mucilage. Although most values approached neutrality, flour showed a lower pH and high density, while greater acidity was observed in the mucilage. Color differed statistically and perceptibly between all samples, with similar values of °hue to purple flours from other sources, and the maximum chroma was found in lyophilized pulp and lightness in fiber. Average moisture levels around 7.2% and water activity levels of 0.303 (0.194 for whole flour) in fractions suggested favorable storability, while the interaction of the powders with water was similar to other root and tuber powdered derivatives. Yampee periderm had the highest swelling power, oil absorption capacity, water holding capacity, and absorption index and capacity. Mucilage had a higher solubility index and outstanding emulsion activity, greater than 90%. Twelve anthocyanins, with new reports of petunidin derivatives for the species, and more than 30 phytochemicals were identified through advanced liquid chromatography techniques. The greatest amounts of pinitol and myo-inositol were found in the mucilage, and sucrose, glucose, and fructose prevailed in the other powders. Successfully characterized yampee fractions showed high potential as functional food ingredients. Full article

The snow melting and runoff process in the black soil area of Northeast China has led to soil quality degradation in farmland, posing a threat to sustainable agricultural development. To investigate the regulatory effect of tillage layer construction on the infiltration characteristics of snowmelt water, a typical black soil in Northeast China was selected as the research object. Based on field experiments, four protective tillage treatments (CK: control treatment; SB: sub-soiling treatment; BC: biochar regulation treatment; SB + BC: sub-soiling tillage and biochar composite treatment) were set up, and the evolution of soil physical structure, soil thawing rate, snow melting infiltration characteristics, and the feedback effect of frozen layer evolution on snowmelt infiltration were analyzed. The research results indicate that sub-soiling and the application of biochar effectively regulate soil aggregate particle size and increase soil total porosity. Among them, at the 0–10 cm soil layer, the soil mean weight diameter (MWD) values under SB, BC, and SB + BC treatment conditions increased by 6.25%, 16.67%, and 19.35%, respectively, compared to the CK treatment. Sub-soiling increases the frequency of energy exchange between the soil and the environment, while biochar enhances soil heat storage performance and accelerates the melting rate of frozen soil layers. Therefore, under the SB + BC treatment conditions, the maximum soil freezing rate increased by 21.92%, 5.67%, and 25.12% compared to the CK, SB, and BC treatments, respectively. In addition, sub-soiling and biochar treatment effectively improved the penetration performance of snowmelt water into frozen soil layers, significantly enhancing the soil’s ability to store snowmelt water. Overall, it can be concluded that biochar regulation has a good improvement effect on the infiltration capacity of surface soil snowmelt water. Sub-soiling can enhance the overall snowmelt water holding capacity, and the synergistic effect of biochar and deep tillage is the best. These research results have important guiding significance for the rational construction of a protective tillage system model and the improvement of the utilization efficiency of snowmelt water resources in black soil areas. Full article

Drought is the most significant abiotic stress that impedes agroforestry development. In nature, drought tolerance also depends on the ability to compensate after water restoration. Dark septate endophytes (DSEs) are believed to enhance plant tolerance in drought environments. However, the compensatory mechanisms of DSEs for rehydration after drought stress have not been reported. To assess the drought tolerance and compensatory capacity of DSEs, the following DSEs were investigated in this study using solid–liquid screening and potting tests under different drought gradients, rehydration conditions, and field water-holding capacities: Stagonosporopsis lupini, Microsphaeropsis cytisi, Macrophomina pseudophaseolina, Paraphoma radicina, Alternaria alstroemeriae, Alternaria tellustris, and Papulaspora equi. The results showed that M. pseudophaseolina reached the maximum diameter for plate growth in only 4 d. In a liquid shaker, the biomass of S. lupini peaked after rehydration. The Mantel heatmap indicated that lipid metabolites were significantly expressed in M. pseudophaseolina and S. lupini under drought stress. Correlations between drought tolerance indexes and amino acid metabolites increased dramatically in both DSEs after rehydration. Moreover, in rehydration after drought, the treatments inoculated with M. pseudophaseolina and S. lupini showed significant increases in root weight of 20.36% and 23.82%, respectively, compared with the uninoculated treatment. Full article

The application of biochar can effectively enhance soil organic matter (SOM) and improve soil structure. Biomass power plant ash (BPPA) is also rich in essential nutrients for plants, with similar carbon content. Considering production cost and agricultural waste recycling, it is beneficial to apply BPPA to improve soil fertility and quality. However, it remains unclear whether its ameliorative effects surpass those of biochar in alkaline soils. In the study, we set up seven pot experiments of faba beans in sandy alkaline soils from the ancient region of the Yellow River, including the controls (CK), different amounts of acid-modified BPPA (A1, A2, A3), and the same amounts of acid-modified biochar (B1, B2, B3), to compare their effects on soil physiochemical properties and bacterial community structure. The results indicate that the application of both biochar and BPPA can improve soil physiochemical properties. At the same dosage, the biochar application outperformed BPPA treatment in terms of soil physical properties such as bulk density (BD), maximum water-holding capacity (FC), and soil capillary porosity (SP2). Conversely, BPPA treatment displayed advantages in chemical properties such as readily oxidizable organic carbon (ROOC), total nitrogen (TN), alkaline nitrogen (AN), available phosphorus (AP), available potassium (AK), and electrical conductivity (EC). All the treatments enhanced the richness and diversity of bacterial communities, increasing the relative abundance of eutrophic groups such as Bacteroidota and Firmicutes while decreasing that of oligotrophic groups like Actinobacteriota. BPPA also increased the relative abundance of Proteobacteria, while the opposite was observed for biochar. Correlation analysis showed that the environmental factors such as soil pH, EC, TN, AK, SOM, and SP2 emerged as primary factors influencing the bacterial community structure of alkaline soils, significantly affecting their diversity and abundance. Among them, SP2 and SOM were the dominant physical and chemical factors, respectively. Overall, the application of both acid-modified BPPA and biochar can enhance the physiochemical properties of sandy alkaline soils, while the application of BPPA is superior for improving soil nutrient content and enhancing bacterial community structure. The study explores the potential mechanisms through which the application of acid-modified BPPA affects soil characteristics and microbial features, providing new insight into developing optimizing fertilization strategies for enhancing soil quality in the ancient region of the Yellow River. Full article