Low-temperature exposure during the early stage of seed imbibition markedly constrains seedling emergence in direct-seeded crops. Recalcitrant seeds are commonly accepted to be highly sensitive to low temperatures. Although Panax notoginseng seeds are characterized by recalcitrance, physiological and molecular responses to low temperature remain poorly defined. Herein, P. notoginseng seeds from three-year-old plants were treated at 0, 4, 10, and 25 °C for 24 or 48 h and analyzed by the method of integrated physiological biochemistry, transcriptomics, and lipidomics. Relative to other temperatures at 48 h, the 0 °C treatment significantly delayed germination, whereas neither 0–4 °C reduced the final germination rate. At 4 °C, reactive oxygen species (ROS) levels exceeded those at 0 °C at 24 h and 48 h, accompanied by increased catalase (CAT) activity. Compared with the 25 °C treatment at 24 h and 48 h, both the 0 °C and 4 °C treatment suppressed phospholipase D (PLD) activity, with a significant inhibition at 0 °C treatment. PLD is a membrane-associated phospholipase that contributes to stress-induced phospholipid hydrolysis. Suppressed PLD activity at 0 °C and 4 °C suggests tighter restriction of membrane lipid catabolism, consistent with enhanced membrane integrity under low temperature. Transcriptome profiling showed that relative to the 25 °C treatment for 48 h, both the 0 °C and 4 °C treatment consistently enriched pathways for unsaturated fatty-acid biosynthesis and elongation, mitogen-activated protein kinase (MAPK) signaling, abscisic acid (ABA) pathway, and phosphatidylinositol signaling. Lipidomics further revealed temperature-specific remodeling: lysophosphatidylcholine, LPC (16:0) accumulated specifically at the 0 °C treatment, whereas phosphatidylcholine, PC (34:1), phosphatidic acid, PA (34:1), and the glycerolipids diacylglycerol (DG) and triacylglycerol (TG) accumulated at 4 °C treatment. Integrative analysis revealed that both PA and LPC are associated with transport and signaling genes. This study also identified the ABA core module centered on pyrabactin resistance 1-like proteins (PYLs) and protein phosphatase 2Cs (PP2Cs) whose module eigengene was negatively correlated with electrolyte conductivity and negatively correlated with phospholipase D activity. This inverse relationship suggests that ABA signaling helps maintain membrane integrity. It may reduce electrolyte leakage and limit PLD-driven lipid hydrolysis. In conclusion, recalcitrant P. notoginseng seeds appear insensitive to low temperature at 0 °C and 4 °C. Changes in the membrane-lipid microenvironment initiate an integrated signaling mechanism that transduces signals via the core ABA pathway. This integrated mechanism ultimately converges on NAM, ATAF1/2, and CUC2 (NAC) transcription factors and dehydration-responsive element-binding protein (DREB) transcription factors to coordinate stress responses.

Introduction:Paris polyphylla is an endangered medicinal herb valued for its steroidal saponins, yet the phenotypic stability, genetic diversity, and quality differentiation of cultivated populations remain insufficiently understood. Methods:In this study, 28 representative populations from Yunnan Province were evaluated under common-garden conditions using morphological, molecular, cytogenetic, genomic and phytochemical analyses. Results:The populations showed generally synchronized phenological development but differed significantly in several agronomic traits. DNA barcoding based on ITS and trnL-trnF sequences achieved high amplification and sequencing success. Among the representative sequences examined, ITS exhibited greater haplotype richness and sequence variation than trnL-trnF. However, because each population was represented by only one consensus sequence, within-population variation and a conventional DNA barcode gap could not be evaluated. Flow cytometry and chromosome counting confirmed that all populations were diploid, although substantial variation in genome size and karyotype characteristics was observed. HPLC analysis further revealed marked differences in steroidal saponin composition and content among populations.Correlation analyses linked saponin variation to multiple agronomic traits, karyotypic features, and genome size. Exploratory partial least squares path modeling showed that temperature was positively associated with plant growth, whereas plant growth was negatively associated with the composite saponin profile. The model explained a limited proportion of the variation in the endogenous constructs, and the identified paths were interpreted as statistical associations rather than causal effects. Discussion:Overall, this study clarifies the genetic and ecological drivers of saponin variation in cultivated P. polyphylla, providing an integrated framework for germplasm identification, quality evaluation, and sustainable utilization of cultivated resources.

The development of under-forest economy within agroforestry systems can enhance the efficiency of land and forest resource utilization, protect the ecological environment, and promote the sustainable development of forests. Forest understory American ginseng (Panax quinquefolius L.) often experiences spatial variability in light availability. However, the impact of light intensity under reduced spatial heterogeneity on soil microenvironments and the regulation of plant physiological traits to promote P. quinquefolius growth remains insufficiently explored. This study adopts field experiments in forest ecosystems to explore how light intensity influences P. quinquefolius physiology, soil biochemical properties, and microbial communities under reduced light spatial heterogeneity. The results indicate that, under reduced spatial heterogeneity with a light transmittance of 13.1

In plants, certain small chemical molecules can elicit immune responses that enable them to enhance resistance against pathogen invasion. To develop a safe and efficient strategy for controlling Paris polyphylla root rot, this study systematically evaluated the resistance-inducing effects and underlying molecular mechanisms of exogenous thiamine and nano-silicon. In vitro assays showed that thiamine and nano-silicon markedly inhibited Fusarium oxysporum mycelial growth and spore germination, with maximum inhibition rates of 30.25 % and 14.03 %, respectively. Pot experiments revealed that 15 mmol & sdot;L 1 thiamine and 150 mg & sdot;L 1 nano-silicon achieved control efficacies of 92.66 % and 88.32 %, respectively, against root rot. Physiological analyses indicated that both elicitors enhanced phenylalanine ammonia-lyase (PAL) and catalase (CAT) activities, promoted the accumulation of total phenolics, and elevated salicylic acid (SA) and jasmonic acid (JA) levels, thereby activating systemic acquired resistance (SAR). Transcriptomic profiling revealed that thiamine treatment was associated with the upregulation of genes involved in SA-and JA-related defence responses, including pathogen perception, MAPK-WRKY signalling, and phenylpropanoid metabolism, whereas nano-silicon treatment showed transcriptional signatures related to ROS regulation, antioxidant enzymes, and multiple hormone-associated pathways. Notably, the combined application of thiamine and nano-silicon did not display synergistic effects. Collectively, both thiamine and nano-silicon induced multilayered defence signalling that conferred systemic resistance of P. polyphylla to Fusarium infection, of which nano-silicon exhibited superior disease control potential and practical applicability. These findings provide new theoretical and practical insights into the eco-friendly management of root rot in P. polyphylla.

Seed dehydration tolerance is a critical physiological trait determining post-harvest survival and species dispersal. While methionine (Met) enhances plant stress adaptation, its role in seed dehydration tolerance remains poorly defined. This study employed integrated transcriptomic and metabolomics analyses to compare Met metabolism during seed development in dehydration-tolerant Panax vietnamensis var. fuscidiscus and dehydration-sensitive Panax notoginseng, sister species exhibiting similar morphology but divergent dehydration tolerance despite equivalent maturity timing. Present study identified significantly higher (P < 0.01) Met accumulation in tolerant seeds at maturity. This divergence was driven by developmentally upregulated expression of key Met biosynthesis enzymes-cystathionine gamma-synthase (CGS), methionine synthase (MS), and Sadenosylmethionine synthetase (SAMS) in P. vietnamensis var. fuscidiscus, contrasting with downregulation in P. notoginseng. Consequently, tolerant seeds exhibited superior antioxidant enzyme (SOD, POD, CAT) activity and glutathione-mediated reactive oxygen species (ROS) scavenging capacity during dehydration. Crucially, exogenous application of the Met synthesis inhibitor DL-propargylglycine (PAG) to tolerant P. vietnamensis var. fuscidiscus seeds suppressed Met accumulation, reduced antioxidant enzyme activity, impaired glutathione system function, compromised membrane integrity (increased electrolyte leakage), and diminished seed vigor and germination under dehydration stress. These results demonstrate that developmentally regulated Met metabolism, mediated by CGS, MS, and SAMS, critically governs seed dehydration tolerance. Met acts as a critical metabolite, enhancing tolerance primarily by bolstering redox homeostasis (via elevated antioxidant and glutathione system activity) and contributing to osmotic adjustment. This study elucidates a key molecular mechanism underlying dehydration tolerance variation in seeds and provides a theoretical foundation for improving storage strategies, particularly for recalcitrant species.

Insomnia compromises both physical and psychological well-being, significantly diminishing quality of life and underscoring the demand for safe, functional foods. This study developed a sleep-enhancing solid beverage utilizing the typically discarded stems and leaves of Panax notoginseng (SLPN). The optimized extract was enriched with bioactive compounds—including saponins, polyphenols, polysaccharides, and key somnogenic amino acids—and exhibited robust antioxidant activity alongside effective α-glucosidase inhibition. In a zebrafish insomnia model, the beverage significantly improved sleep disturbances, evidenced by reduced locomotor activity and upregulated levels of GABA and melatonin. These findings demonstrate that SLPN is a valuable, sustainable resource for the development of sleep-supporting functional foods.

Agriforestry systems are essential for improving the quality of medicinal herbs and ensuring the sustainable management of forests. Forest soil acidification inhibits the growth of medicinal plants. The application of novel dolomite-loaded vermicompost (DOVC) is considered a potential method for promoting plants growth. However, the mechanisms by which it promotes the growth of medicinal plants are poorly understood. This study combined observational analysis and field experimentation, to first elucidate the correlation between under-forest soil pH and root dry weight of American ginseng (Panax quinquefolius L.). Subsequently, the mechanisms by which DOVC promotes the growth of P. quinquefolius were analyzed from the perspectives of plant physiology and soil microbiome. The results indicate: (1) Field survey results demonstrated when the pH was between 5.28 and 5.99, the root dry weight of P. quinquefolius gradually increased with increasing soil pH. (2) Compared with Control, DOVC increased the soil pH by 1.48 units and promoted the growth of P. quinquefolius, with a net photosynthetic rate increase of 60.26%, malondialdehyde content decrease of 71.07%, and root dry weight increase of 50.33%. (3) Compared with Control, DOVC enhanced bacterial community diversity, with Ace and Chao 1 indices increasing significantly by 33.88% and 25.18%, respectively; and increased the relative abundance of Chloroflexi and Basidiomycota. (4) Partial Least Squares Path Modeling revealed that DOVC positively influenced P. quinquefolius growth via the improvement of soil health index and microbial community diversity. The development of this novel soil amendment offers a new approach to improving soil health in agroforestry systems.

Background Panax notoginseng, a traditional Chinese medicinal herb, holds significant historical and clinical value due to its ability to promote blood circulation, alleviate blood stasis, and provide neuroprotective effects. The primary bioactive constituents of this herb are P. notoginseng saponins (PNS). However, the mechanisms underlying the biosynthesis and regulation of PNS remain inadequately understood. Methods The contents of notoginsenoside R1, ginsenosides Rg1, Re, Rb1, and Rd in P. notoginseng roots were determined using high-performance liquid chromatography. The protein composition of P. notoginseng roots was digested and labeled by tandem mass tags, and high pH reverse phase separation, analyzed using low pH nano high performance liquid chromatography-mass spectrometry (pH nano-HPLC-MS/MS) analysis system. Key protein data and regulatory pathways in the roots of P. notoginseng were analyzed to identify the essential enzymes and their corresponding genes involved in ginsenoside synthesis. Results A total of 7578 proteins were identified, among which 252 differentially expressed proteins (DEPs) were characterized. Specifically, 155 were found to be downregulated, while 93 were upregulated in the comparison of high to low (H/L) ginsenoside content. The DEPs were primarily associated with biological processes, molecular functions, and cellular components, as classified by Gene Ontology. Additionally, Kyoto encyclopedia of genes and genomes pathway enrichment analysis revealed a significant involvement of the ribosomal pathway. Notably, 19 enzymes identified among the DEPs are linked to ginsenoside biosynthesis. Conclusions This study analyzed the differences in the content of five major ginsenosides in P. notoginseng roots and identified the key proteins (enzymes) involved in regulating ginsenoside synthesis. The findings highlight the regulatory roles of the cytochrome P450 (CYP450) and UDP-glycosyltransferase (UGT) enzyme families in the biosynthetic pathways of secondary metabolites, providing valuable insights into the biosynthesis of the active medicinal components in P. notoginseng.

Ulcerative colitis (UC) prevalence is increasing in Asia, with limited treatment options. Increasing treatment needs for UC warrant exploration of ethnopharmacological resources. This study validated the ethnopharmacological application of the bark of Zanthoxylum myriacanthum var. pubescens (Maqian) (MQEB) for gastrointestinal inflammation by evaluating its dual mechanisms against UC pathogenesis. In vitro analyses employed lipopolysaccharide (LPS)-stimulated RAW 264.7 macrophages and Caco-2 intestinal epithelial cells treated with MQEB (10-40 mu g/mL), quantifying cytokine profiles via enzyme-linked immunosorbent assay (ELISA). In vivo studies utilized dextran sulfate sodium (DSS)-induced colitis in C57BL/6 mice administered oral MQEB (125, 250, or 500 mg/kg) or salicylazosulfapyridine (SAL, 300 mg/kg), with assessments of disease activity index (DAI), histopathology, tight junction protein expression, and toll-like receptor 4 (TLR4)/nuclear factor-kappa B (NF-kappa B) pathway modulation. MQEB significantly attenuated colitis severity through dose-dependent suppression of pro-inflammatory cytokines (tumor necrosis factor-alpha (TNF-alpha), interleukin-1 beta (IL-1(3), IL-6, IL-17), inhibition of TLR4/NF-kappa B signaling, and restoration of intestinal barrier integrity via upregulation of tight junction proteins (zona occludens-1 (ZO-1), Claudin5). Safety assessments confirmed absence of hepatorenal toxicity, supporting MQEB as a multi-target botanical therapeutic for UC.

Plant-derived polysaccharides are increasingly recognized as promising anti-aging agents due to their potent bioactivities and low toxicity. As the principal bioactive constituents of Polygonati Rhizoma (PR), polysaccharides undergo defined structural transformations during the traditional "Nine Steaming-Nine Sun-Drying" processing. This study first reveals two novel polysaccharides: RPR-N2 (5.5 kDa) from raw PR, featuring a unique fructan backbone [→1)-β-D-Fruf-(2→] anchored to a →6)-α-D-Glcp-(1→ core with →1,6)-β-D-Fruf-(2→ branches, and PPR-N2 (10.5 kDa) from processed PR, which evolves into a branched galactan with →4)-β-D-Galp-(1→ main chains, →4,6)-β-D-Galp-(1→ linkages, and side chains. A β-fructan (RPR-N2) from raw PR was transformed into a branched β-galactan (PPRN2) after processing. Both polysaccharides significantly attenuated H₂O₂-induced senescence in MRC-5 fibroblasts through multiple mechanisms: (1) reducing senescence-associated β-galactosidase (SA-β-Gal) activity; (2) enhancing proliferation and antioxidant defenses; (3) mitigating G₁-phase cell cycle arrest; (4) restoration of mitochondrial membrane potential; and (5) suppressing senescence-associated secretory phenotype (SASP) factor secretion. This study investigated the structural evolution of PR polysaccharides during processing and established their potential as nutraceutical agents for aging modulation. The results provide a scientific foundation for the optimization of traditional processing methods.

Photosynthesis plays a critical role in plant growth and development, with light intensity being a primary factor in optimizing photosynthetic efficiency and the biosynthesis of secondary metabolites. Succinic acid, an active ingredient in the medicinal plant Pinellia ternata with analgesic effects, exhibits light-dependent accumulation patterns, potentially regulated by the HY5 transcription factor through photosynthetic-TCA cycle crosstalk. Comparative analyses of photosynthetic capacity, succinic acid content, and gene expression under full light (100 %FL) and shaded conditions (55 %FL) revealed that 55 %FL enhanced chlorophyll content by 873.74 μg g-2 and photosynthetic rates by 33 %, accompanied by HY5-mediated upregulation of light-harvesting genes. Improved leaf area and mesophyll structure under shading facilitated light absorption and CO2 diffusion, whereas 100 %FL suppressed photosynthetic genes and electron transport, reducing succinic acid content by 27 %. Transcriptomic profiling identified light intensity-dependent metabolic shifts, with HY5-associated downregulation of TCA cycle genes (SDH1-1/SDH2-1) correlating negatively with succinic acid accumulation. These findings demonstrate that moderate shading promotes growth and bioactive compound synthesis in P. ternata through HY5-coordinated optimization of photosynthetic and respiratory pathways. This study highlights the potential of leveraging HY5-driven light signaling in agricultural practices to enhance medicinal plant quality, offering precision strategies for cultivation optimization through targeted light regulation.

DNA methylation plays a crucial role in regulating fruit ripening and seed development. It remains unknown about the dynamic characteristics of DNA methylation and its regulation mechanisms in morpho-physiological dormancy (MPD)-typed seeds with recalcitrant characteristics. The P. notoginseng seeds are defined by the MPD and are characterized by a strong sensitivity to dehydration during the after-ripening process. We performed DNA methylomes, siRNA profiles, and transcriptomes of embryo and endosperm in P. notoginseng seeds at different after-ripening stages. Herein, we find that the CHH hyper-methylation contributes to the global increase in DNA methylation during the after-ripening process of P. notoginseng seeds. The endosperm genome is hyper-methylated compared to the embryo genome. The CHH hyper-methylation is caused by the high expression level of DNA methyltransferase PnCMT2 in the embryo, and PnDRM2 in the endosperm, respectively. The CHH hyper-methylation alters gene transcription levels to regulate the after-ripening and dormancy of recalcitrant seeds. For example, it inhibits the expression of genes in embryo development to make seeds maintain a dormant status, whereas it activates the expression of genes in the hormone-mediated signaling pathway, and energy metabolism to accomplish the MPD-typed seed after-ripening process. Together, our findings reveal a global increase in DNA methylation and its vital driver in gene expression, and thus elucidate how global CHH hyper-methylation regulates the after-ripening in recalcitrant MPD-typed seeds. This work establishes a key role for epigenetics in regulating the dormancy of MPD-typed seeds with recalcitrant characteristics.

Four new compounds, dimethyl 3,5-bis(4-hydroxyphenyl)-1H-pyrrole-2,4-dicarboxylate (1), dimethyl 3,5-bis(4-hydroxyphenyl)-1H-furan-2,4-dicarboxylate (2), 5α-hydroxy-6β-methoxy-ergosta-7,22E-dien-3-one (3), and 6-methoxy-strophasterol E (4), together with sixteen known compounds (5-20), were isolated from the fruiting bodies of Lanmaoa asiatica. The structures of new compounds were elucidated by extensive spectroscopic analysis and electronic circular dichroism (ECD) calculation. Among them, compounds 2, 4, 7, and 9 exhibited anti-inflammatory activity by suppressing NO production in lipopolysaccharide-stimulated RAW264.7 macrophages with IC50 values ranging from 20.3 to 47.3 μM.

Prolonged continuous cropping has the potential to negatively impact soil health, leading to a disruption in the natural succession of Panax notoginseng. Sustainable agricultural practices, such as crop rotation and the application of biological agents, have been shown to enhance soil health and productivity. However, there is a paucity of information on the efficacy of combining these strategies for enhancing soil health. This study pioneered the use of Perilla frutescens rotation in plots with P. notoginseng continuous cropping soil. After crushing the harvested perilla and returning it to the plots, Trichoderma harzianum Rifai strain TH7 was applied. Fallow and continuous P. notoginseng cultivating plots served as controls. One - year - old P. notoginseng seedlings were then transplanted. The mechanism of perilla residues and T. harzianum application in shaping soil microbial communities was also analyzed. Results showed that the perilla aqueous extract with T. harzianum effectively controlled key P. notoginseng pathogens like Fusarium solani, Fusarium oxysporum, and Cylindrocarpon destructans, without inhibiting TH7 growth. The soil quality index (SQI) of fallow soil exhibited a significant increase of 149.16 % compared to that of continuously cropped soil. By contrast, the SQI increased by 161.70 % following perilla rotation, residue return, and subsequent application of T. harzianum. The survival rate of replanted P. notoginseng was about 19 % after fallow or perilla rotation, versus 5.38 % under continuous cropping. However, it rose to 29.23 % with T. harzianum application post- perilla rotation and residue return. These results highlight the effectiveness of integrated agricultural practices in restoring soil health and productivity. This approach of applying T. harzianum post-perilla rotation and incorporating perilla residues significantly improved soil health, enhancing microbial activity and nutrient availability. It also greatly boosted the survival rate of replanted P. notoginseng, offering a new strategy to overcome P. notoginseng continuous cropping obstacles and being highly significant for sustainable agricultural development. The combined effects of crop rotation and biological agent application not only address the immediate challenges of soil degradation but also promote long-term soil fertility and resilience. This integrated strategy represents a promising advancement in sustainable farming practices, particularly for high-value crops like P. notoginseng that are sensitive to soilborne diseases and nutrient imbalances.

Dendrobium officinale flowers possess anti-aging and nourishing properties for the skin; however, there is a notable deficiency in pharmacological research concerning chronic obstructive pulmonary disease (COPD). To investigate the effects of Dendrobium officinale flower extract (DOFE) on the amelioration of COPD, 29 flavonoids present in DOFE were identified and quantified, which demonstrate antioxidant and anti-inflammatory properties. Pathological observation, RNA-Seq and ScRNA-seq analysis revealed that DOFE treatment decreased the up-expression of genes caused by cigarette smoke (CS), which includes receptors (TLR, TNFR, and NOD), transcription factors (AP-1, STAT1), and key proteins (HSP90, A20, MKP) that contribute to the generation of reactive oxygen species and activation of the NF-kappa B and NLRP inflammasomes. This resulted in a decrease in secretion of IL-1R, IL-5, MIP-1 alpha, and MIP-1R in neutrophils and macrophages, suppressed the increase in alveolar macrophages. Together, DOFE alleviated pulmonary inflammation, restored antioxidant capacity, and prevented COPD induced by CS.

Planting vegetation under forests in agroforestry systems fosters sustainable agricultural development. However, Limited availability of biostimulants for agroforestry and unclear mechanisms of plant growth promotion. This study synthesized and evaluated a novel biostimulant, nanosilicon-based vermicompost leachate (NSVCL), using Panax quinquefolius L. as the research plant species for forest cultivation. Trichoderma harzianum (TH) was chosen to represent a biostimulant with broad-spectrum properties, and its application effects were compared with NSVCL. The regulatory effects of both on the physiological characteristics and rhizosphere soil microenvironment of P. quinquefolius were investigated, with untreated plants serving as controls. Compared to the control, NSVCL and TH increased the dry weight of P. quinquefolius roots 129.33 % and 23.50 %, respectively. NSVCL was applied more effectively than TH. Additionally, NSVCL markedly improved leaf anatomical traits, including palisade and spongy tissue thickness, overall leaf thickness, chloroplast number, and cuticle thickness. Application of NSVCL and TH significantly elevated the net photosynthetic rate (Pn) by 86.55 % and 60.92 %, respectively, and increased total chlorophyll content (TChl) by 24.91 % and 11.76 %. Biostimulants facilitated nutrient uptake and boosted antioxidant enzyme activity in P. quinquefolius. Partial least squares path modeling (PLS-PM) further demonstrated that both NSVCL and TH promoted plant growth by enhancing soil enzyme activity in forest environments. These findings underscore NSVCL's efficacy in improving P. quinquefolius growth under forest conditions and provide a practical foundation for advancing organic forest cultivation and sustainable forest-medicine integration.

Increasing planting density is an effective strategy for enhancing the yield potential of summer maize; however, it substantially elevates the risk of lodging under adverse weather conditions such as heavy rainfall and strong winds. Under these circumstances, potassium fertilizer plays a progressively critical role in improving lodging resistance. Previous studies have primarily focused on the individual effects of planting density and potassium fertilizer application rate on maize lodging resistance and yield, with less emphasis on their integrative effects in the lodging resistance process. In this study, two maize varieties differing in lodging resistance—Denghai 605 (DH605, lodging-resistant) and Xianyu 335 (XY335, lodging-susceptible)—were used as experimental materials. Three treatments were established: T1 (density, 67,500 plants ha−1; K2O, 180 kg ha−1), T2 (density, 82,500 plants ha−1; K2O, 180 kg ha−1), and T3 (density, 82,500 plants ha−1; K2O, 270 kg ha−1), to examine the mechanism through which concurrent increases in planting density and potassium fertilizer application rate affect lodging resistance and yield formation of summer maize. In terms of yield improvement, the T3 treatment demonstrated a significant advantage, increasing the two-year average yield of DH605 and XY335 by 18.65 and 16.05%, respectively, compared to T1, and by 7.25 and 14.36% relative to T2. In terms of lodging resistance, T3 promoted stem thickening and root system expansion while enhancing the activity of lignin biosynthesis-related enzymes (PAL, TAL, and CAD) in both stems and brace roots. This facilitated increased synthesis and accumulation of lignin, thereby strengthening mechanical properties. Consequently, the T3 treatment reduced lodging rate by 30.45% (DH605) and 29.42% (XY335) compared to T1, and by 51.21 and 55.90% compared to T2. Overall, concurrent increases in planting density and potassium fertilizer application rate achieved dual improvements in both yield and lodging resistance in summer maize. This approach provides a crucial reference for mitigating lodging risks under projected extreme weather events and ensuring high and stable production of summer maize.

Panax notoginseng are attacked by several pathogens that cause root rot disease. Under pathogen infection, PR proteins accumulate to protect plants and enhance systemic acquired resistance. Studies have shown that PR genes in P. notoginseng are crucial for root rot resistance. However, genome-wide identification of PR genes in P. notoginseng remains limited. We identified 152 PR genes from the PR1, PR2, PR3, PR4, PR5, PR10, PR12, PR15, and PR17 families through conserved domain analysis. Transcriptomic and weighted gene co-expression network analysis revealed that PR genes play a crucial role in defense against Ilyonectria destructans infection. Furthermore, nine of these genes were consistently upregulated after infection and exhibited distinct expression patterns following treatments with salicylic acid and methyl jasmonate. PnPR4 was significantly upregulated after I. destructans infection, as well as after salicylic acid and methyl jasmonate treatments. When expressed in tobacco, PnPR4 enhanced resistance to Fusarium oxysporum. This suggests that PnPR4 confers broad-spectrum resistance in P. notoginseng, playing a key role in defense against root rot pathogens.

Background:This study aimed to examine the effects of intensive cultivation practices on the rhizosphere microecology of Panax notoginseng. Additionally, we sought to compare these practices with an understory cultivation model that was intended to mimic native growth conditions, with the objective of improving the quality of Radix Notoginseng. Methods:The total saponin and active ingredient content in both cultivation methods were quantified using high-performance liquid chromatography (HPLC). The nutrients of the rhizosphere soils associated with both cultivation methods (understory cultivated P. notoginseng rhizosphere soil [UCPS] and intensive cultivated P. notoginseng rhizosphere soil [ICPS]) were analyzed. The microbial communities present in UCPS and ICPS were characterized using metagenomic sequencing. Results:The underground biomass accounted for 71.21 % and 74.00 % of the total biomass in understory cultivated P. notoginseng (UCPn) and intensively cultivated P. notoginseng (ICPn), respectively. The total saponin content in the main root of UCPn was found to be 109.24 ± 3.40 mg/g, compared to 91.31 ± 5.82 mg/g in ICPn. The concentration of medicinal ingredients (ginsenoside Rb1 + ginsenoside Rg1 + notoginsenoside R1) in UCPn was 10.83 %, while ICPn exhibited a higher concentration of 13.39 %. Microbial biomarkers identified in UCPS include Bradyrhizobium, Pseudomonas, and Paraburkholderia, which are associated with nitrogen cycling processes. In contrast, Variovorax and Sphingobium were predominant in ICPS, contributing to phosphorus metabolism. Conclusion:Rhizosphere soil microbial biomarkers influence soil carbon nutrition, which directly impacts the quality of UCPn. The quality of ICPn is primarily determined by phosphorus-related biomarkers, with indirect influences from carbon and nitrogen nutrition.

IntroductionThe deep application of controlled-release urea (CRU) offers potential advantages for crops with extended growth periods. However, its effects on P. notoginseng yield and quality, a medicinal plant with a prolonged nutrient acquisition duration, remain unclear.MethodsIn this study, we conducted a two-year field plot experiment to investigate the effect of CRU on P. notoginseng with three placement depths (0, 6, and 12 cm denoted as R0, R6, and R12, respectively) at an application dosage of 250 kg N ha-1 with biochar addition (R6B) and 20% N reduction (R6R) based on the R6, with conventional fertilization (250 kg N ha-1, common urea) serving as the control (CK).ResultsOur results indicated that yields increased by 27.1–37.6% with R0, R6, R12, and R6B, while remaining stable with R6R compared to CK. Simultaneously, the total saponin content in the roots of R6, R6B, and R6R was improved by 14.3–38.1%, compared to CK. The distribution depth of soil NO3⁻-N and plant roots increased with the depth of CRU application, with a high overlap in time and space, indicating P. notoginseng N uptake peaked when CRU was applied at a depth of 6 cm (R6). Structural equation modeling indicated that soil NO3⁻-N supply in specific microareas directly affected the N uptake and increased total saponin content by increasing root length and surface area, thus boosting yield.ConclusionThis study identifies that the deep application of CRU at a depth of 6 cm has the potential to enhance both yield and quality of P. notoginseng and highlights that the spatial-temporal matching of soil NO₃⁻-N and plant roots was the key to applying CRU to ensure high yield and quality.