Search Results (98)

Ginkgo biloba is a dioecious species valued for landscaping and medicine, but rapid sex identification outside the flowering and fruiting stages remains challenging. Hyperspectral imaging offers a potential solution, though whether spectral sex markers are stable across phenological stages and can support a single year-round model is unclear. Here, leaf hyperspectral reflectance (400–1000 nm) was acquired from mature G. biloba at flowering (n = 360), green-leaf (n = 1395), and yellow-leaf (n = 243) stages. Sex identification models were built using multiple machine learning classifiers, with leaf flavonoid content as biochemical validation. Stage-specific models achieved optimal test accuracies of 96.67% (flowering, MSC + PLS-DA), 95.77% (green-leaf, raw spectra + LDA), and 97.12% (yellow-leaf, MSC + LDA). However, discriminative bands shifted from the visible (520–690 nm) at the green-leaf stage to the near-infrared (700–1000 nm) at the yellow-leaf stage, with almost no bands shared across all stages. Furthermore, cross-stage prediction accuracy dropped to near-chance levels (~50%). As t-SNE analysis revealed, the universal model had learned phenological rather than sex-specific information. In addition, flavonoid measurements revealed a highly significant sex × stage interaction (p < 0.001) and a reversal of the sex difference between green-leaf (male > female) and yellow-leaf (female > male) stages. Thus, the spectral and biochemical sex markers examined in this study varied substantially with phenology, and stage-specific models are required for practical sex identification in G. biloba. Full article

Dioecious plants often exhibit sex-specific physiological strategies that influence their response to environmental change. However, it is not well understood whether such dimorphism extends to the developmental trajectory of the photosynthetic apparatus during natural senescence. In this study, we compared the seasonal development and decline of photosystem II (PSII) function in naturally grown male and female Ginkgo biloba using non-destructive fast chlorophyll a fluorescence induction kinetics (OJIP) and JIP-test analysis. Sun-exposed, healthy leaves were sampled at approximately 15-day intervals from 18 July to 26 November 2024 [day of year, (DOY 188–332)]. The study monitored chlorophyll content and OJIP-derived parameters, and evaluated sex differences statistically (p < 0.05). Chlorophyll content began to decline after DOY 268 in both sexes, but decreased earlier and more rapidly in males. By DOY 332, male chlorophyll content fell to 1.37% of its level at DOY 268, whereas females retained 9.55%. OJIP fluorescence transient analysis revealed that ΔW_oj shifted from negative to positive values after DOY 268 in male plants, accompanied by a sustained increase in the relative variable fluorescence at the J step (V_j). This pattern indicates an earlier and more pronounced acceptor-side limitation of PSII in male plants, associated with accelerated accumulation of QA⁻ and restricted electron transfer from QA⁻ to QB and the plastoquinone (PQ) pool. In addition, male plants showed a clearer donor-side limitation, with a pronounced ΔW_ok response, suggesting reduced stability of the oxygen-evolving complex (OEC). In contrast, females maintained higher cross-section-based energy fluxes (TR₀/CS₀, ET₀/CS₀) and PSI-end acceptor reduction capacity (RE₀/CS₀), and exhibited a slower decline in integrated performance indices (PI abs, PI total, DF abs). Principal component analysis further suggested that male senescence trajectories were more tightly associated with changes in electron-transport efficiency, whereas females exhibited a more gradual adjustment in energy-flux allocation. Collectively, these results reveal pronounced sexual dimorphism in the PSII–PSI functional decline pathway during natural senescence in G. biloba and provide a physiological basis for understanding sex-specific variation in photosynthetic decline in this species, with potential relevance to broader studies of dioecious plants. Full article

Leaf nitrogen concentration (LNC) is an important indicator of Ginkgo nutritional status, but its hyperspectral estimation remains challenging because leaf spectra are high dimensional, strongly collinear, and affected by overlapping structural and biochemical signals. This study examined how spectral preprocessing, wavelength selection sequence, and regression model choice influence leaf scale Ginkgo LNC estimation, while separating simulation-assisted model development from measured sample-based prediction assessment. We assembled 717 field measured Ginkgo leaf spectra with corresponding laboratory measured LNC values and used PROSPECT-PRO simulated spectra only for wavelength screening or calibration augmentation, not as independent validation data. Three evaluation schemes were compared: measured-only analysis, simulated spectra-assisted wavelength selection followed by measured data calibration and testing, and simulated spectra-assisted wavelength selection and calibration followed by measured-only testing. The third scheme was used as the main inference framework because it retained an independent measured sample test boundary. Within this framework, multiple preprocessing methods, two wavelength selection sequences, and four regression models (PLSR, GPR, 1D-CNN, and DGP) were evaluated. MSC showed comparatively low error in the preprocessing comparison, and CARS-SPA identified a compact set of informative wavelengths concentrated mainly in the shortwave infrared region. Under the simulation-assisted calibration framework, the combination of MSC preprocessing, CARS-SPA wavelength selection, and DGP regression produced the lowest test error on the measured sample set (R² = 0.82; RMSE = 2.07 mg g⁻¹). These results indicate that Ginkgo LNC estimation depends on the combined choice of preprocessing method, wavelength selection strategy, and regression model, and provide a methodological reference for simulation-assisted hyperspectral modeling. Full article

Cardiovascular disease (CVD) represents the leading cause of mortality worldwide, with atherosclerosis (AS) serving as its primary pathological foundation, involving multiple pathological processes, including lipid metabolism disorders, chronic inflammation, and endothelial dysfunction. The food and medicine continuum (FMC) concept originates from traditional Chinese medicine, emphasizing that certain foods possess both nutritional and medicinal value, aligning closely with the modern “food is medicine” philosophy. This narrative review examines the bioactive components and anti-atherosclerotic mechanisms of ten FMC materia medica: hawthorn fruit (Crataegus Fructus), ginkgo seed (Ginkgo Semen), milkvetch root (Astragali Radix), turmeric (Curcumae longae Rhizoma), ginger (Zingiberis Rhizoma Recens), glossy ganoderma (Ganoderma), Angelica sinensis (Angelicae sinensis Radix), barbary wolfberry fruit (Lycii Fructus), lotus leaf (Nelumbinis Folium), and honey (Mel). These materia medica are rich in bioactive constituents, including flavonoids, terpenoids, and polysaccharides, which can exert cardiovascular protective effects, such as regulating lipid metabolism, inhibiting inflammation and oxidative stress, improving endothelial function, and modulating gut microbiota. Regarding clinical evidence, meta-analyses support the beneficial effects of ginger and honey on cardiometabolic risk factors, though the field still faces challenges, including the need for higher-level clinical evidence and difficulties in product standardization. This review aims to integrate traditional knowledge with modern scientific approaches, providing scientific evidence for the development of functional foods and phytotherapy. Full article

Leaves of vascular plants exhibit a tip-to-base xylem conduit widening pattern, which minimizes hydraulic resistance as leaves expand. The extent to which different leaf vein orders conform to this pattern remains largely unexplored, particularly in species with dichotomously branching veins. In this study, we focused on Ginkgo biloba, a model species with dichotomous venation, to explore tracheid variation across leaf vein orders and its linkage with hydraulic path length. Across 108 leaves from three sites, tracheid hydraulic diameter (D) scaled significantly with hydraulic path length (L) at an overall scaling slope of 0.33 (95% CI: 0.31–0.34, r² = 0.53, p < 0.001). Scaling exponents differed significantly among sites and vein orders, and D decreased progressively with increasing vein order. This study provides a potentially valuable approach for investigating the effects of hydraulic path length on xylem conduit diameter and offers a framework for subsequent research on plant venation and hydraulic transport networks. Full article

Globally, the combined pollution of fine particulate matter (PM_2.5) and ground-level ozone (O₃) poses severe challenges to public health and sustainable urban development. Recent data indicate that the annual average PM_2.5 concentration in the vast majority of cities worldwide fails to meet World Health Organization safety standards, with air pollution causing millions of premature deaths annually. As a nature-based solution, the purification efficacy of vegetation remains poorly quantified due to unclear coupling mechanisms with local meteorological conditions. This study systematically reviewed and synthesized 229 empirical studies published between 2000 and 2025 from Web of Science and China National Knowledge Infrastructure (CNKI), aiming to clarify the quantitative relationships and regulatory mechanisms of plant–meteorological synergistic purification of PM_2.5–O₃. Following double-blind independent screening (κ = 0.85) and data extraction, a quantitative minimal feasible synthesis approach was adopted due to high data heterogeneity. The results indicated the following. (1) The median canopy purification efficiency of urban vegetation for PM_2.5 was 18.2% (IQR: 12.5–30.1%, n = 17), with a median dry deposition velocity (Vd–PM) of 0.05 cm s⁻¹ (0.02–30 cm s⁻¹, n = 15). The median dry deposition velocity (Vd–O₃) for O₃ was 0.55 cm s⁻¹ (0.12–1.82 cm s⁻¹, n = 8), with non-stomatal deposition contributing approximately 35%. (2) Meteorological factors exhibit nonlinear regulation: relative humidity (RH) > 70% significantly enhances PM_2.5 adsorption, wind speeds of 1.5–3.0 m s⁻¹ are optimal for PM_2.5 deposition, and temperatures > 30 °C generally inhibit plant uptake of both pollutants (n = 7). (3) Functional traits strongly correlate with purification efficacy: species with high leaf roughness (R² = 0.8), high stomatal conductance, and low BVOC emissions (e.g., Ginkgo biloba, Platycladus orientalis) exhibit optimal synergistic purification potential. Species with high BVOC emissions (Populus przewalskii, Eucalyptus robusta) can increase daily net O₃ pollution equivalents by up to 86 g and must be strictly avoided. Based on quantitative evidence, a green space planning decision matrix indexed by climate zone and pollution type was developed, specifying vegetation configuration patterns, functional group selection, and key design parameters (canopy closure, green belt width, etc.) for different scenarios. This study provides an actionable scientific basis for precision planning and climate-adaptive management of urban green infrastructure. Full article

Ginkgolic acids (GAs), the principal toxic constituents in Ginkgo biloba, pose health risks including cytotoxicity, allergenicity, and pro-inflammatory effects, limiting the application of Ginkgo resources in the food and health product industries. Developing efficient and environmentally friendly removal methods is essential. The endophytic fungus Fusarium sp. DLT-118, isolated from Ginkgo biloba, degraded 96.47% of GAs in Ginkgo biloba leaf extract (GE) at an initial concentration of 1 mg/mL within 7 days at 28 °C, while concurrently enhancing the antioxidant activity of GE, as indicated by a reduction in the 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical scavenging IC₅₀ from 755.7 μg/mL to 544.6 μg/mL. Morphological and oxidative stress analyses showed critical cellular adaptations and stress responses under degradation conditions. Integrated multi-omics analysis indicated that GE stress induced the remodeling of fungal amino acid, lipid, and energy metabolism, as well as the adjustment of membrane and transport functions, to facilitate GAs detoxification. Cytotoxicity assays indicated no significant cytotoxicity of the degradation products towards human normal lung epithelial cells (Beas-2B) and gastric mucosal epithelial cells (GES-1). These findings highlight Fusarium sp. DLT-118 as a promising agent for the efficient removal of GAs, offering a potential strategy for the production of GA-reduced Ginkgo-based food and health products. Full article

Ginkgo biloba L. plays an important role in biodiversity conservation. Accurate identification of Ginkgo in forest environments remains challenging due to its visual similarity to other broad-leaved species during the green-leaf period and to species with yellow foliage during autumn. In this study, we propose a novel two-stage segment-then-classify (STC) strategy to improve the accuracy of Ginkgo identification from unmanned aerial vehicle (UAV) imagery. First, the Segment Anything Model (SAM) was fine-tuned for canopy segmentation across the green-leaf stage and the yellow-leaf stage. A post-processing pipeline was developed to optimize mask quality, ensuring independent and complete tree crown segmentation. Subsequently, a ResNet-101-based classification model was trained to distinguish Ginkgo from other tree species. The experimental results showed that the STC strategy achieved significant improvements compared to the YOLOv8 model. In the yellow-leaf stage, it reached an F1-score of 92.96%, improving by 24.50 percentage points over YOLOv8. In the more challenging green-leaf stage, the F1-score improved by 31.27 percentage points, surpassing YOLOv8’s best performance in the yellow-leaf stage. These findings demonstrate that the STC framework provides a reliable solution for high-precision identification of Ginkgo in forest ecosystems, offering valuable support for biodiversity monitoring and forest management. Full article

This study established an efficient in vitro regeneration system using stem nodes from root collar suckers as explants. Subsequently, regenerated shoots were used to establish an in vitro medicinal production protocol that achieved ginkgolic acid production. The self-developed Ginkgo biloba medium (GBM), first reported in this study, was pivotal to system establishment. The plantlet propagation system showed that the bases of stem nodes dipped in GBM with 2 mg·L⁻¹ 6-benzyladenine (BA) and 0.2 mg·L⁻¹ 1-naphthaleneacetic acid (NAA) achieved near-complete axillary bud induction (99.56%). Adventitious shoot induction reached 82.22% (3.5 shoots/explant) using GBM with 0.2 mg·L⁻¹ BA, 0.02 mg·L⁻¹ kinetin (Kin) and 0.2 g·L⁻¹ proline (Pro). Maximum adventitious shoot elongation (92.22%, average 3.35 cm) was observed on GBM containing 0.1 mg·L⁻¹ zeatin (ZT) and 0.01 mg·L⁻¹ BA. After 3-week preculture with 15 mg·L⁻¹ phloroglucinol (PG), treatment with 0.6 mg·L⁻¹ indole-3-butyric acid (IBA) and 0.2% activated carbon (AC) yielded 96.67% rooting (6.19 roots/explant) and 85% acclimatization survival. For medicinal resource production, bud cluster induction at 94.44% (20.89 buds/explant) on GBM with 1 mg·L⁻¹ BA, 0.03 mg·L⁻¹ Kin, and 0.2 g·L⁻¹ Pro. Leaf organs in GBM with 0.3 mg·L⁻¹ BA, 0.01 mg·L⁻¹ Kin, 0.01 mg·L⁻¹ IBA, 0.3 g·L⁻¹ Pro, and 0.01 mg·L⁻¹ glutamine (Gln) accumulated 20.64 g fresh weight and 41.910 mg·g⁻¹ DW ginkgolic acids, representing a 4.93-fold increase over mother plants. This system enables large-scale Ginkgo biloba L. propagation and provides an in vitro strategy for producing medicinal compounds in endangered plants. Full article

Ginkgo biloba is one of the most consumed medicinal plants and broadly included as an ingredient in plant food supplements (PFS) and herbal infusions, being potential targets for economically motivated adulteration. This work aimed at comparing the use of DNA and phytochemical markers to authenticate the botanical origin of ginkgo-leaf extracts and PFS. Quantitative real-time PCR was used to detect ginkgo DNA, while ultra-high performance liquid chromatography with tandem mass spectrometry detection (UHPLC-MS/MS) determined its main phytochemicals (terpene lactones and flavonol aglycones). DNA was detected in all ginkgo leaf extracts, mainly water, while the highest levels of phytochemicals were obtained using ethanol or acetone as solvents. The results suggested that 4 out of a total of 19 PFS samples were adulterated, with two samples evidencing the addition of quercetin from sources other than ginkgo. The other two samples showed low amounts of ginkgo phytochemicals, which was corroborated by low DNA content, suggesting the use of reduced amounts of G. biloba leaf material. Full article

Ginkgo biloba leaf flavonoids, while demonstrating antioxidant potential, remain underexplored as natural stabilizers for frying oils under thermo-oxidative stress. This study assessed Ginkgo biloba leaf flavonoids efficacy against synthetic tertiary-butylhydroquinone (0.02%). Ginkgo biloba leaf flavonoids were extracted via optimized ultrasonic-assisted methods (15 mL/g solvent, 80% ethanol, 45 °C, 120 s). Frying stability in flaxseed and soybean oils over 6 days (24 cycles/day) was evaluated using multi-indicator kinetic analysis. Ginkgo biloba leaf flavonoids significantly outperformed tertiary-butylhydroquinone in reducing oxidation markers after 6 days. In flaxseed oil, Ginkgo biloba leaf flavonoids reduced acid value (18.4%), peroxide value (33.79%), and polar compounds (52.03%); reductions in soybean oil reached 61.34% for polar compounds. Ginkgo biloba leaf flavonoids better preserved γ-tocopherol in flaxseed oil (increased 2.09% retention) and key tocopherols in soybean oil. Critically, it mitigated unsaturated fatty acid losses (flaxseed C18:3: 2.72% higher; soybean C18:2: 4.4% higher) and limited saturated fatty acid increases. Optimized Ginkgo biloba leaf flavonoid extraction facilitates its application as a promising natural candidate for high-temperature frying, where its matrix-specific stabilization effect shows potential in commercial functional oil formulations. Full article

Climate change poses significant threats to urban tree health and survival worldwide. This study evaluates climate suitability risks for 12 common tree species in Wuhan, a Chinese metropolis facing escalating climate challenges. We analyzed risk dynamics and interspecific variations across three periods, the baseline (1981–2022), near future (2023–2050), and distant future (2051–2100), quantifying climate risk as differences between local climate conditions and species’ climatic niches. We further examined how species’ geographic distribution and functional traits influence these climate risks. The results revealed significant warming trends in Wuhan during the baseline period (p < 0.05), with projected increases in temperature and precipitation under future scenarios (p < 0.05). The most prominent risk factors included the precipitation of the driest month (PDM), annual mean temperature (AMT), and maximum temperature of the warmest month (MTWM), indicating intensifying drought–heat stress in this region. Among the studied species, Cedrus deodara (Roxb.) G. Don, Platanus acerifolia (Aiton) Willd., Metasequoia glyptostroboides Hu & W.C.Cheng, and Ginkgo biloba L. faced significantly higher hydrothermal risks (p < 0.05), whereas Koelreuteria bipinnata Franch. and Osmanthus fragrans (Thunb.) Lour. exhibited lower current risks but notable future risk increases (p < 0.05). Regarding the factors driving these interspecific variation patterns, the latitude of species’ distribution centroids showed significant negative correlations with the risk values of the minimum temperature of the coldest month (MTCM) (p < 0.05). Among functional traits, the wood density (WD) and xylem vulnerability threshold (P50) were negatively correlated with precipitation-related risks (p < 0.05), while the leaf dry matter content (LDMC) and specific leaf area (SLA) were positively associated with temperature-related risks (p < 0.05). These findings provide scientific foundations for developing climate-adaptive species selection and management strategies that enhance urban forest resilience under climate change in central China. Full article

Understanding species-specific mechanisms governing symbiotic fungal responses to plant traits and soil factors is critical for optimizing urban tree “plant-soil-fungus” systems under pollution stress. To address this gap, we combined δ¹³C/δ¹⁵N isotope analysis and ITS sequencing for three common street trees in Beijing: Sophora japonica, Ginkgo biloba, and Populus tomentosa. In S. japonica, symbiotic fungal abundance was positively associated with leaf δ¹⁵N, indicating root exudate-mediated “plant-microbe” interactions during atmospheric NO_x assimilation. G. biloba, with weak NO_x assimilation, exhibited a negative correlation between fungal abundance and soil available N/P, suggesting mycorrhizal nutrient compensation under low fertility. P. tomentosa showed decreased fungal abundance with increasing soil N/P ratios and specific leaf area, reflecting carbon allocation trade-offs that limit mycorrhizal investment. These results demonstrate that symbiotic fungi respond to atmospheric and edaphic drivers in a tree species-dependent manner. Urban greening strategies should prioritize S. japonica for its NO_x mitigation potential and optimize fertilization for G. biloba (nutrient-sensitive fungi) and P. tomentosa (nutrient balance sensitivity). Strategic mixed planting of P. tomentosa with S. japonica could synergistically enhance ecosystem services through complementary resource acquisition patterns. This study provides mechanism-based strategies for optimizing urban tree management under atmospheric pollution stress. Full article

Nitrogen nutrition monitoring is crucial in agriculture and forestry. With the development of Unmanned Aerial Vehicle (UAV) imaging technology, its application in nitrogen nutrition monitoring has gained attention. Traditional regression methods often struggle to accurately capture the nonlinear relationships between image features and nitrogen nutrition parameters. This study introduces Gaussian regression models to better model the relationship between UAV image features and nitrogen nutrition in Ginkgo. UAV RGB imagery of three-year-old Ginkgo biloba L. seedlings was used to extract nitrogen-related image features. Gaussian regression models were employed to select and model these features, creating regression models for nitrogen accumulation and nitrogen content in Ginkgo. The accuracy of the models was validated. Results indicated that the optimal canopy type for monitoring nitrogen accumulation in Ginkgo was the shadowed canopy, with the color feature BMR being the most important feature. For monitoring nitrogen content, sunlight and shadow canopy types were suitable, with BMR and b* being the key features. Gaussian regression demonstrated superior accuracy and robustness compared to traditional regression models. This study emphasizes the potential of Gaussian regression models to improve nitrogen monitoring through UAV imagery, offering valuable applications in precision agriculture and forestry management, particularly in supporting nitrogen fertilization and nutrition management for Ginkgo. Full article

Drought stress is one of the key environmental factors restricting the germination of alfalfa seeds (Medicago sativa L.). Nanopriming is an innovative seed-priming technology able to meet economic, agronomic, and environmental needs in agriculture. However, the use of conventional nanomaterials is hampered by high costs, environmental risks, and biotoxicity. In this study, we synthesized iron oxide nanoparticles (Fe₃O₄NPs) using seasonal Ginkgo biloba leaf extracts (collected from August to November) obtained via an enzymatic ultrasonic-assisted method. The synthesized Fe₃O₄NPs were characterized using SEM, EDS, DLS, FTIR, UV-Vis, and XRD. To investigate the effects of Fe₃O₄NP priming on alfalfa seed germination under drought stress, germination and pot experiments were conducted with five Fe₃O₄NP priming concentrations (unprimed, 0, 20, 40, and 60 mg/L) and three PEG-6000 concentrations (0%, 10%, and 15%) to simulate normal, moderate, and severe drought conditions. The results showed that leaf extracts collected in November exhibited the highest flavonoid content (12.8 mg/g), successfully yielding bioactive-capped spherical Fe₃O₄NPs with a particle size of 369.5 ± 100.6 nm. Germination experiments revealed that under severe drought stress (15% PEG-6000), the 40 mg/L Fe₃O₄NP treatment most effectively enhanced seed vigor, increasing the germination rate, vigor index, and α-amylase activity by 22.1%, 189.4%, and 35.5% (p < 0.05), respectively, compared to controls. Under moderate drought stress (10% PEG-6000), the 20 mg/L Fe₃O₄NP treatment optimally improved germination traits, increasing the germination rate by 25.5% and seedling elongation by 115.6%. The pot experiments demonstrated morphological adaptations in alfalfa seedlings: under moderate drought stress, the 40 mg/L Fe₃O₄NPs significantly increased lateral root numbers, while under severe drought stress, the 60 mg/L Fe₃O₄NPs increased the root surface area by 20.5% and preserved the roots’ structural integrity compared to controls. These findings highlight that Fe₃O₄NPs synthesized via Ginkgo leaf extracts and enzymatic ultrasonic methods exhibit promising agricultural potential. The optimal Fe₃O₄NP priming concentrations enhanced seed vigor, germination traits, and drought resistance by modulating root morphology, with concentration-specific efficacy under varying drought intensities. Full article