Nicotinamide mononucleotide (NMN), a precursor in nicotinamide adenine dinucleotide (NAD) biosynthesis, has long been recognized for its pivotal role in medicine. Recent investigations have suggested its potential as a plant immunity inducer for controlling fungal diseases. However, whether NMN confers plant broad-spectrum resistance against diverse phytopathogens, and its underlying mechanisms remain ambiguous. In this study, we investigate the effect of NMN against multiple phytopathogens in tobacco. Our results demonstrate that tobacco pretreated with NMN exhibits enhanced resistance against Rastonia solanacearum CQPS-1, Pseudomonas syringae DC3000 ∆hopQ1-1, Phytophthora parasitica, and tobacco mosaic virus (TMV). NMN displays effectiveness within the concentration range of 50-600 μM, with 75 μM NMN exhibiting the most pronounced effect. The impact of NMN pretreatment could persist for up to 10 days. Beyond tobacco, NMN pretreatment enhances disease resistance in tomato and pepper plants against diverse pathogens, underscoring NMN's capacity to confer broad-spectrum disease resistance in crops. Moreover, RT-qPCR analysis reveals that NMN significantly upregulates the expression of the pattern-triggered immunity (PTI) marker gene NbCYP71D20 and salicylic acid (SA) marker gene NbPR1a. This suggests that NMN enhances plant resistance by inducing both PTI and SA-mediated immunity. Interestingly, the positive impact of NMN on plant disease resistance is not significantly compromised in both NMN adenylyltransferase (NMNAT)-silenced plants and NAD receptor mutant lecrk-I.8, suggesting the existence of NAD-independent signaling pathways for NMN-induced plant immunity. In conclusion, our study establishes that the bioactive molecule NMN imparts broad-spectrum disease resistance in plants, offering a simple, environmental-friendly, and promising strategy for safeguarding crops against diverse phytopathogens. These findings also provide valuable insights for future in-depth studies into the functional mechanisms of NMN.

In the Shangluo region of China, Salvia miltiorrhiza plants have been observed with black-brown necrosis on the aerial parts, while the roots retain an intact epidermis but display internal rot that can be easily crushed by hand. A pathogen was consistently isolated from the diseased roots and, based on colony morphology, was identified as a member of the genus Phytopythium. Molecular identification based on partial sequences of four gene regions—the nuclear ribosomal internal transcribed spacer (ITS), mitochondrial cytochrome c oxidase subunits I and II (cox I and cox II), and β-tubulin—confirmed the morphological classification and revealed that the isolate represents a previously undescribed Phytopythium species, designated Phytopythium shangluoense after its geographic origin. Detached root inoculation assays demonstrated that P. shangluoense could cause complete root rot of S. miltiorrhiza within 15 days. Within the temperature range of 13–28 °C, seedling disease incidence reached 100% within three days after inoculation. Additionally, a set of genus-specific primers based on the ITS region was designed and validated, allowing sensitive and accurate discrimination of Phytopythium spp. from other known root pathogens of S. miltiorrhiza. Furthermore, dual culture assays and subsequent pot assays demonstrated that Streptomyces fungicidicus strain FYA1 exhibits significant inhibitory effects against P. shangluoense, achieving an efficacy of 80% against root rot caused by this pathogen. This study provides the first confirmed evidence of the isolation and designation of P. shangluoense and demonstrates that it is an aggressive oomycete plant pathogen capable of independently causing root rot and plant death in S. miltiorrhiza, offering critical insights for early diagnosis and integrated disease management.

Scutellaria baicalensis Georgi is a perennial medicinal plant, but the relationships between root flavonoid accumulation and abiotic factors, including geography, climate, and soil, as well as biotic factors such as rhizosphere fungi, remain poorly understood. In this study, S. baicalensis plants and their rhizosphere soils were collected from 50 regions across China to examine the associations of geographic, climatic, and soil factors, together with rhizosphere fungi, with eight flavonoid compounds. Flavonoid contents varied significantly among production areas, whereas flavonoid composition was not significantly correlated with geographic distance. Redundancy analysis identified six climatic variables, seven soil variables, and eight rhizosphere fungal taxa as significant factors associated with flavonoid composition. Based on correlation patterns, the eight flavonoids were classified into two clusters. Canonical analysis further showed that variation in total flavonoids and in the two clusters was associated with both environmental factors and rhizosphere fungi. Partial least squares path modeling showed that climatic factors had the strongest positive direct associations with total flavonoids and Cluster 2, whereas soil factors showed the strongest positive direct association with Cluster 1. Rhizosphere fungal beta-diversity also showed positive direct associations with both clusters. These findings suggest that coordinated flavonoid modules are associated with distinct environmental and microbial factors. Overall, these results provide a basis for developing quality-oriented cultivation strategies for S. baicalensis.

Fritillaria taipaiensis is a commercially important medicinal herb, the bulbs of which are a valued source of steroidal alkaloids with potent antitussive and expectorant properties. However, the mechanisms underlying the tissue-specific biosynthesis of these bioactive compounds remain poorly understood, limiting strategies for their enhanced production. This study, we integrated UPLC-MS/MS-based metabolomics with multi-tissue transcriptomics to elucidate the steroidal alkaloid biosynthetic pathway in F. taipaiensis. Comparative metabolomic profiling revealed distinct tissue-specific accumulation patterns, with bulbs serving as the primary site for therapeutically relevant steroidal alkaloids such as peimisine, edpetiline, and delafrine. Transcriptomic analysis unveiled metabolic compartmentalization, characterized by the bulb-specific upregulation of mevalonate (MVA) pathway genes, contrasting with leaf-predominant expression of methylerythritol phosphate (MEP) pathway components. This indicates a tissue-specific partitioning of precursor supply. Of note, we identified bulb-specific isoforms FrtSSR1 (encoding a Δ²⁴(²⁵)-reductase) and FrtSMO1-1 (encoding a C-4 demethylase), which were highly expressed and are proposed to pivotal roles in redirecting metabolic flux toward cholesterol biosynthesis. Furthermore, the coordinated induction of cytochrome P450 enzymes in bulbs suggests their involvement in mediating structural diversification of the steroidal skeleton. Our findings systematically unravel the molecular basis of bulb-specific steroidal alkaloid accumulation, highlighting pathway specialization, enzyme subfunctionalization, and CYP450-mediated modification. This study provides a genetic foundation and key candidate genes for future metabolic engineering and molecular breeding strategies aimed at improving the yield of high-value steroidal alkaloids in Fritillaria species.

Scutellaria baicalensis Georgi is a perennial medicinal plant, but the relationships between root flavonoid accumulation and abiotic factors (geography, climate, and soil) as well as biotic factors such as rhizosphere fungi remain poorly understood. In this study, S. baicalensis plants and their rhizosphere soils were collected from 50 regions across China to examine the associations of geographic, climatic, and soil factors, together with rhizosphere fungi, with eight flavonoid compounds. Flavonoid contents varied significantly among production areas, whereas their spatial distribution was not significantly correlated with geographic distance. Redundancy analysis identified six climatic variables, seven soil variables, and eight rhizosphere fungal taxa as significant factors associated with flavonoid composition. Based on correlation patterns, the eight flavonoids were classified into two clusters. Canonical analysis further showed that total flavonoid concentration and the concentration of each cluster were significantly correlated with both environmental factors and rhizosphere fungi. Partial least squares path modeling revealed that climatic factors exerted the strongest direct effects on total flavonoids and Cluster 2, whereas soil factors had the strongest effect on Cluster 1. Rhizosphere fungal beta diversity also had significant direct effects on both clusters. These findings indicate that coordinated flavonoid modules are shaped by distinct environmental drivers. Climatic conditions were more strongly associated with Cluster 2, whereas the soil microenvironment had a greater influence on Cluster 1. Overall, these results provide a basis for quality-oriented cultivation strategies for S. baicalensis.

Simultaneously enhancing plant growth and disease resistance is an ideal goal in Agriculture. Significant efforts have been made to promote plant growth or immunity through the use of biological reagents, such as the application of beneficial microbes and plant immunity inducers. However, balancing plant immunity and growth remains a challenging task. In this study, we engineered the plant growth-promoting bacterium Bacillus subtilis OKB105 to express a secreted microbial pattern, flg22, and accessed its activity in enhancing both plant growth and disease resistance. The OKB105 (flg22) strain exhibited plant growth-promoting activity similar to the OKB105 strain containing an empty vector, OKB105 (EV). Furthermore, the OKB105 (flg22) strain significantly enhanced plant resistance against two distinct pathogens, Pseudomonas syringae DC3000 ΔhopQ1-1 and Phytophthora parasitica, compared to OKB105 (EV), confirming that the engineered OKB105 (flg22) effectively enhances plant disease resistance. Interestingly, root irrigation with OKB105 (flg22) also markedly boosted the plant’s aboveground resistance to pathogens compared to OKB105 (EV). We further demonstrated that OKB105 (flg22) can be applied to confer resistance to pathogens in other plants that recognize flg22. Finally, RNA-Seq and qRT-PCR analyses illustrated that OKB105 (flg22) effectively induced the expression of defense-related genes in pattern-triggered immunity. Our results prove that employing an engineered beneficial microbe expressing a microbial pattern is a promising strategy for simultaneously enhancing plant growth and immunity.

Na and Cu in rhizosphere soil, along with endophytic fungi such as Plectosphaerella and Hannaella, are positively correlated with the total content of 35 alkaloids in Fuzi. The relationships among geographical and climatic factors, soil nutrients, endophytic fungi, and alkaloids in Fuzi (Aconitum carmichaelii Debx.), as well as which factor predominantly affects alkaloid accumulation, remain insufficiently understood. To elucidate these interactions and optimize alkaloid production, we collected Fuzi plants and rhizosphere soil from 26 regions across China. Alkaloid profiles were analyzed using UPLC-Q–TOF–MS/MS, endophytic fungal communities by amplicon sequencing, and soil properties through standard chemical analysis. Redundancy analysis, random forest modeling, and canonical correspondence analysis revealed that geographic distance, climatic factors including average temperature and precipitation during the wettest and warmest months, and soil nutrients including available P, exchangeable Al, Cu, and Na, along with endophytic fungi such as Gibberella and Acremonium significantly influenced alkaloid composition. The total alkaloid content was positively correlated with endophytes Plectosphaerella, Hannaella, and Gibellulopsis, and with rhizosphere soil exchangeable Cu and Na, but negatively associated with Ilyonectria and exchangeable Mn. Canonical analysis showed that endophytic fungi explained 42.9

The distribution patterns of antibiotic resistomes in biological soil crusts (biocrusts) and the underlying factors influencing them remain poorly understood. Here, metagenomic sequencing was used to profile antibiotic resistomes in biocrusts of urban green space soils in 54 cities across China. The biocrust samples harbored ARGs associated with resistance against 21 classes of antibiotics such as betalactams, quinolones, aminoglycosides, and tetracyclines. Total ARG abundance was positively correlated with total phosphorus, available phosphorus, and lignin concentrations in biocrusts. The geographic factors, environmental factors, and DOM components only explained 18.1 % of the total variation of resistome in 54 samples, whereas the bacterial and mobile genetic element (MGE) communities explained 59.3 % of the total variation. In contrast with deterministic processes, stochastic processes played a more dominant role in shaping the resistomes across different samples (average stochasticity: 81.2 %) and were correlated with MGE communities. Findings of the present study demonstrate the ecological distribution of antibiotic resistomes in biocrusts of urban green spaces under different biotic and abiotic conditions over a continental scale.

Bulb rot in Fritillaria taipaiensis P. Y. Li, caused by Fusarium spp., is a destructive soil-borne disease that severely affects the yield and quality of F. taipaiensis. Chemical fungicides are currently the primary means of controlling this disease; however, their use poses risks to human health and the environment. Biological control is thus a preferable alternative to counteract the threats associated with pathogens. In this study, an endophytic bacterium, designated SJ22, was isolated from bulb tissue of F. taipaiensis, and it exhibited significant antagonism against Fusarium spp., with inhibition rates on plates ranging from 84.35% to 89.96% and a control rate of 73.38% in pot experiments. Morphological observations and phylogenetic analyses identified the isolate SJ22 as Bacillus velezensis. Furthermore, the antifungal mechanisms of SJ22 include the inhibition of spore germination, alteration of hyphal morphology, and disruption of cell membrane integrity. Its volatile organic compounds exhibited broad-spectrum antifungal activity in vitro, with an inhibition rate of 28.36% to 59.12%, and demonstrated significant control efficacy in vivo. Transcriptome analysis revealed that SJ22 induced systemic resistance in F. taipaiensis by upregulating defense-related genes, primarily through enhancing the phenylpropanoid biosynthesis pathway and promoting the salicylic acid/ethylene signaling pathway to induce the production of pathogenesis-related proteins and increase the activity of defense-related enzymes. In summary, we isolated an endophytic bacterium that exerts its biocontrol function through both inhibiting pathogen growth and inducing resistance.

The ability to efficiently screen plant pathogen effectors is crucial for understanding plant-pathogen interactions and developing disease-resistant crops. Traditional methods are often labor-intensive and time-consuming. Here, we present a robust, high-throughput screening assay using the tobacco mosaic virus-green fluorescent protein (TMV-GFP) vector system. The screening system combines the TMV-GFP vector and Agrobacterium-mediated transient expression in the model plant Nicotiana benthamiana. This system enables the rapid identification of effectors that interfere with plant immunity (both activation and suppression). The biological function of these effectors can be easily evaluated within six days by observing the GFP fluorescence signal using a UV lamp. This protocol significantly reduces the time required for screening and increases the throughput, making it suitable for large-scale studies. The method is versatile, cost-effective, and can be adapted to effectors with immune interference activity from various pathogens. Key features • A robust, cost-effective, and high-throughput functional screening system for plant pathogen effectors. • Utilizes the TMV-GFP vector for rapid monitoring of effector activity. • Evaluates the function of effectors within a few days using just a UV lamp. • Adaptable to both apoplastic and cytoplasmic effectors from various phytopathogens.

Chinese herbal medicines have become a new green feed additive in the aquaculture industry. The aim of this study is to investigate the effects of traditional Chinese herbal medicines (Isatidis radix, Forsythia suspensa, and Schisandra chinensis) on the growth performance, antioxidant capacity, and intestinal microbiota of hybrid snakehead (Channa maculata ♀ × Channa argus ♂). A total of 600 fish (mean weight: 15.85 ± 0.15 g) were randomly assigned to five groups, including the control group (CG), I. radix extract group (IRE), F. suspensa extract group (FSE), S. chinensis extract group (SCE), and the Chinese herbal medicine mixture group (CHMM; a mixture of extracts of I. radix, F. suspensa, and S. chinensis at the ratio of 1:1:1) for 6 weeks. The results show that the IRE-supplemented diet improved the survival rate (SR), feed efficiency ratio (FE), and condition factor (CF) compared to others. Compared to the control group, the activity of superoxide dismutase (SOD) in plasma and intestine was significantly increased in the FSE and CHMM groups, whereas the content of malondialdehyde (MDA) in plasma and liver was significantly reduced in the SCE group. A 16s rRNA analysis indicates that dietary supplementation with FSE significantly promoted the proliferation of Fusobacteriota, while IRE supplementation increased the alpha diversity of intestinal bacteria. In conclusion, the addition of I. radix to the diet of hybrid snakehead improves growth, antioxidant capacity, and liver and intestine health, and modulates the intestinal microbiota of snakehead positively.

Taibai Beimu (Fritillaria taipaiensis P. Y. Li) is a traditional Chinese herb renowned for its use in alleviating respiratory ailments. In June of 2022 and 2023, an incidence 10 to 20% of foliage symptoms, including yellowing and wilting, was observed in a 10-hectare Taibai Beimu field located in Shangluo, Shaanxi Province (33.64° N, 106.72° E). The middle and stem-adjacent areas of the infected bulbs had brown to black lesions that rotted entirely in severe cases. Fifty symptomatic bulbs were cut into 4 × 4 mm pieces at the junction of the diseased and healthy parts. These pieces were sterilized in 2% sodium hypochlorite for 2 min, followed by 75% ethanol for 30 s, and then rinsed with sterile water. The segments were placed on potato dextrose agar (PDA) and incubated at 28℃ for 5 days in darkness. The morphological characteristics were observed on PDA and synthetic low-nutrient agar (SNA). Sixteen isolates showing similar morphological characteristics were obtained. Representative isolate FTC1 was selected for further analysis. After five days, the mycelial colony on PDA was covered with tomentose aerial mycelia in white or light red. On SNA, the microconidia were oval or rod-shaped, measuring 5.9 to 11.0 × 1.4 to 2.9 µm (average 8.5 × 2.2 µm, n = 50), while the macroconidia were falcate, slender, and curved with an elongated apical cell, usually 1 to 3 septa and ranged from 22.0 to 78.2 × 1.4 to 2.9 µm (average 50.2 × 2.4 µm, n = 50). The morphology was consistent with a previous description of Fusarium avenaceum (Sun et al. 2022). The internal transcribed spacer (ITS) region, translation elongation factor 1-α (EF-1α), RNA polymerase II largest subunit (RPB1), and RNA polymerase II second largest subunit (RPB2), were amplified from extracted genomic DNA with the primer pairs ITS1/ITS4 (White et al. 1990), EF1/EF2 (O'Donnell et al. 1998), RPB1U/RPB1R (Ponts et al. 2020), and 5F2/7cR (Reeb et al. 2004), respectively. BLASTn queries of NCBI GenBank revealed a 100%, 99.7%, 99.6% and 99.1% homology with F. avenaceum (MH864972, MZ153160, MW024696 and MZ078939), respectively. The sequences were deposited in GenBank (ITS, PP879197; EF-1α, PQ106669; RPB1, PQ106668; RPB2, PP554893). The phylogenetic analysis of the multilocus sequences of the isolate FTC1 was conducted using the maximum likelihood method with MEGA11.0 (Tamura et al. 2007). The isolate FTC1 was grouped with F. avenaceum strains NRRL 54939, NRRL 53729 and NRRL 26911; therefore, the isolate FTC1 was identified as F. avenaceum. To fulfill Koch's postulates, fresh FTC1 hyphae were inoculated in 250 ml of potato dextrose broth (PDB) on a shaker at 180 rpm and 28℃ for three days. The spores were filtered through four layers of gauze and adjusted to 1 × 106 spores/ml with sterilized water. Five healthy five-year-old plants were inoculated with 20 ml of spore suspensions, while PDB was used as a control. The inoculation involved pouring the spore suspension over a bulb and covering it with sterile nutrient soil. All plants were grown in sterile nutrient soil in artificial climate chambers (MRC-1100C, Ningbo Prandt Instrument, China) set to 20℃, 80% relative humidity, under a 12-h photoperiod. After 21 days, the plants inoculated with the pathogen exhibited symptoms identical to those observed in the field, while all control plants remained healthy. The pathogen was re-isolated from the symptomatic bulbs, which was confirmed both morphologically and molecularly, as described earlier. F. avenaceum has been reported as a pathogen of Chinese medicinal herbs, such as Polygonatum cyrtonema (Xu et al. 2019) and Coptis chinensis (Mei et al. 2021). To our knowledge, this is the first report of F. avenaceum infecting Taibai Beimu in China, posing threats to its production.

Sporocarps of macrofungi support other diverse fungal species that are termed fungicolous fungi. However, a pipeline for the simultaneous processing and analysis of macrofungi and their fungicolous fungi, in addition to the external environmental factors that affect the diversity and composition of fungicolous fungal communities, remains largely unknown. In this study, a novel specialized pipeline was constructed to automatically analyze the sequence diversity of host macrofungi along with their associated fungicolous fungi. Moreover, the alpha and beta diversities of fungicolous fungal communities residing in host macrofungi from diverse habitats in the Qinling Mountains were analyzed, revealing that the diversity and composition of fungicolous fungal communities varied with host growth month and habitats. Furthermore, saprophytic fungi had greater abundances of cell wall degrading enzymes than parasitic and symbiotic fungi, potentially explaining why saprophytic fungi grew more abundant on wood, and revealing the formation mechanism of “small islands” growing on wood.

Sporocarps of macrofungi support other diverse fungal species that are termed fungicolous fungi. However, the external environmental factors that affect the diversity and composition of fungicolous fungal communities remains largely unknown. In this study, the diversities, composition, and trophic modes of fungicolous fungal communities residing in host macrofungi from diverse habitats in the Qinling Mountains were analyzed. Additionally, the number of carbohydrate-active enzymes (CAZymes) encoded by saprophytic, pathogenic, and symbiotic fungi was also quantified and compared. The results revealed that the diversity and composition of fungicolous fungal communities varied with months of collection and the habitats of host fungi, and saprophytic fungi were more abundant on wood than on the ground. Meanwhile, it was also found that saprophytic fungi possessed higher abundances of cell-wall-degrading enzymes than pathogenic or symbiotic fungi. Based on the above findings, it was hypothesized that the greater abundance of saprophytic fungi on wood compared to the ground may be due to their possession of a more diverse array of enzymes capable of degrading wood cell walls, thereby allowing for more efficient nutrient acquisition from decaying wood.

Aconitum carmichaeli Debx. (Ranunculaceae) is a traditional Chinese medicine with large-scale artificial cultivation in China. Potassium fertilizer is commonly supplemented to increase the yield of lateral roots of A. carmichaeli. This study aims to reveal the effect of inorganic potassium fertilizer on rhizosphere microbial communities and the dissolved organic matters (DOMs). Furthermore, the relationship between DOMs and microbial community variation is studied. A pot cultivation experiment of A. carmichaeli in a greenhouse was conducted. The low, medium, and high amounts of potassium sulfate, potassium chloride, and potassium humate were supplemented for each treatment. The yield of A. carmichaeli lateral roots was weighed, and the alkaloids’ contents were measured. Soil properties, DOMs, and soil microorganisms communities were analyzed. The yield of A. carmichaeli lateral roots was enhanced in PHM (medium amount of potassium humate) and PCM (medium amount of potassium chloride). The dissolved organic carbon contents in the PSM (medium amount of potassium sulfate), PSH (high amount of potassium sulfate), PCL (low amount of potassium chloride), and PCH (high amount of potassium chloride) were 7.24 ± 0.32 g·Kg− 1, 7.68 ± 0.50 g·Kg− 1, 8.54 ± 0.22 g·Kg− 1 and 8.58 ± 0.38 g·Kg− 1 respectively, which were significantly decreased compared to the control. The Shannon index of the fungal community increased in PHL (low amount of potassium humate), reaching 7.42 ± 0.17, 7.07 ± 0.44, and 7.52 ± 0.12, respectively. Besides, it was decreased in PCL (5.69 ± 1.58), PCM (6.41 ± 0.82), and PSL (low amount of potassium sulfate) (6.78 ± 0.90). The proportions of Acidobacteria were reduced in the PSL (10.29

The pharmacological properties of the dried root of Scutellaria baicalensis Georgi, a Chinese medicinal herb, include antioxidant, antibacterial, and antiviral effects. In S. baicalensis quality assessment, concentrations of baicalin, wogonoside, baicalein, and wogonin in the root are crucial. Drought stress commonly affects the biomass and build-up of active compounds in medicinal sections of medicinal plants and thus their quality. The molecular mechanisms underlying the response of S. baicalensis to drought stress remain unexplored. To delve into the impacts of drought stress on the growth and metabolic processes of S. baicalensis, as well as to unravel the underlying molecular mechanisms. We found prolonged and intensified drought treatment causes an initial surge in its fresh weight, plant height, and stem diameter followed by a gradual slowdown, while malondialdehyde (MDA) content rises; while the fresh weight, length, superoxide dismutase (SOD), and catalase (CAT) activities peak before declining, and the root’s diameter continuously narrows. In this study, flavonoid index ingredient levels in S. baicalensis initially decreased, then rose as the drought duration extended, followed by a notable post-rehydration increase in baicalin, wogonoside, and baicalein content and decrease in levels of wogonin and oroxylin A. Transcriptome sequencing and KEGG analysis revealed a significant enrichment of DEGs involved in phenylpropanoid biosynthesis and plant hormone signal transduction pathways. The expression levels of SbPAL, SbCCL, Sb4CL, SbCHI, SbFNSII, SbF6H, and SbUGT genes in the flavonoid biosynthetic pathway and PYR/PYL, PP2C, ABF, and SnRK2 genes in the abscisic acid signal transduction pathway were significantly changed. Drought responsive SbWRKY34 was selected for the subsequent investigation. SbWRKY34 showed the highest level in stems, and the encoding protein was localized in the nucleus. Overexpression of SbWRKY34 in Arabidopsis thaliana (OE-SbWRKY34 lines) resulted in increased sensitivity to drought stress, with considerably reduced MDA content and elevated SOD and CAT activities. Concurrently, the expression levels of AtCAT3, AtDREB, AtRD22, AtRD29A, and AtRD29B were significantly reduced in these lines, suggesting that SbWRKY34 functions to negatively regulate drought resistance in A. thaliana.

Fritillaria taipaiensis P. Y. Li (F. taipaiensis) is a traditional Chinese herbal medicine that has been used for over two millennia to treat cough and expectoration. However, the increasing cultivation of F. taipaiensis has led to the spread of bulb rot diseases. In this study, pathogens were isolated from rotten F. taipaiensis bulbs. Through molecular identification, pathogenicity testing, morphological assessment, and microscopy, Fusarium solani was identified as the pathogen causing bulb rot in F. taipaiensis. The colonization of F. solani in the bulbs was investigated through microscopic observation. The rapid and accurate detection of this pathogen will contribute to better disease monitoring and control. Loop-mediated isothermal amplification (LAMP) and qPCR methods were established to quickly and specifically identify this pathogen. These results provide valuable insights for further research on the prediction, rapid detection, and effective prevention and control of bulb rot in F. taipaiensis.

This study systematically explored the copigmentation effects of lignan extracts, lignan eluent fractions, and individual lignans from Schisandra sphenathera and Schisandra chinensis fruits on the anthocyanins enriched with petunidin-3-O-glucoside. The results showed that two ethanol extracts contained higher levels of lignans and were more effective in copigmentation reactions than their water counterparts. The isolation of ethanol extracts on macroporous resin rendered a large proportion of lignans enriched in 95% EtOH eluent fractions, one of which from S. sphenathera exhibited the strongest ability to stabilize the color. Meanwhile, correlational analyses suggested that six lignans, namely, schisandrol A, schisandrol B, schisantherin A, schisantherin B, schisandrin A, and schisandrin B, were the major active copigments that thermodynamically stabilize the target anthocyanins, with schisandrin B being the best one. Moreover, the structure-function relationships of these compounds revealed that the biaryl backbone was essential for copigmentation, which can be enhanced by the aromatic methylenedioxy groups.

In order to clarify the natural habitat characteristics of Schisandra sphenanthera in Qinling Mountains and its response to different light conditions, the methodology of community quantitative analysis was applied to categorize and rank the natural clusters of S. sphenanthera. At the same time, the ecological niche width of S. sphenanthera and the degree of niche overlap with the main shrub species were measured.Furthermore, the rapid chlorophyll fluorescence induction curves of leaves under different light conditions were measured as well. The results show that the habitats of S. sphenanthera in the Qinling Mountains could be divided into four categories: northern subtropical coniferous forest; warm temperate coniferous and broadleaved mixed forest; warm temperate deciduous and broad-leaved mixed forest, and evergreen, deciduous and broad-leaved mixed forest. Among the shrub layers of the four habitats, S. sphenanthera is ranked the top 20% in the importance value, and is one of the main species of understory shrubs. The forward selection and Mente Carlo test were performed on seven environmental factors, and finally, two ecological factors, canopy closure and slope position, were screened out, and a total of 79% of the environmental information was extracted.Among the various habitats, S. sphenanthera has a wider niche width and a larger niche overlap with other understory shrubs, indicating that it has strong interspecific competition with understory shrub species. Under full-light condition without shading, the specific leaf area（SLA） and the maximum photochemical quantum yield of PSII both decrease, and there is an obvious K point in the chlorophyll fluorescence fast kinetic curve（OJIP）. It indicates that the strong light inhibits the photosynthetic efficiency of leaves and may affect the energy distribution pattern of the plant. All four types of natural habitats of S. sphenanthera are shaded under the canopy, and excessive light can lead to a decrease in its photosynthetic efficiency. It is suggested that the natural habitat should be simulated as much as possible in artificial ecological cultivation, and appropriate shade should be provided.

Rationale and objectives: Fuzi, the dried root of Aconitum carmichaelii Debx, is one of the widely used traditional Chinese medicines. Fuzi polysaccharides are considered the most bioactive compounds with immunomodulatory functions, however, the mechanisms have not been evaluated. This study aims to systematically investigate the effects of Fuzi polysaccharides on the gut microbiota and immune function using a mouse model immunosuppressed with cyclophosphamide. Methods: The short-chain fatty acid levels in cecal contents were measured by gas chromatography-mass spectrometry. The gut microbiota 16S rRNA gene were sequenced by next generation sequencing. The mRNA expression levels of NF-κB, IL-6, TNF-α, iNOS and COX-2 were measured using quantitative real-time polymerase chain reaction. The protein expression of occludin and zonula occludens-1 were analyzed by Western blot. The white blood cells were counted using automated hematology analyzer, and CD4+FOXP3+/CD4+ ratio was measured by flow cytometry. Results and Conclusions: Fuzi polysaccharides had the function of elevating the concentration of acetic acid, propionic acid, isobutyric acid, and n-butyric acid in the cecum. Meanwhile, Fuzi polysaccharides could decrease the relative abundance of Helicobacter, Anaerotruncus, Faecalibacterium, Lachnospira, Erysipelotrichaceae_UCG-003, Mucispirillum, and Mycoplasma, and increase the relative abundance of Rhodospirillales, Ruminococcaceae_UCG-013, Mollicutes_RF39, Ruminococcus_1, Christensenellaceae_R-7_group, and Muribaculaceae in the gut. Furthermore, Fuzi polysaccharides exhibited the function of increasing spleen and thymus indices and number of white blood cells and lymphocytes. Fuzi polysaccharides could reverse the decreased mRNA expression of NF-кB, IL-6, and iNOS, differentiation of CD4+FOXP3+ regulatory T cells as well as protein expression of occludin and zonula occludens-1 induced by cyclophosphamide. In addition, the mRNA and protein expression of cytokines were significantly correlated with the abundance of gut microbiota under Fuzi polysaccharides treatment. Collectively, the above results demonstrated that Fuzi polysaccharides could regulate inflammatory cytokines and gut microbiota composition of immunosuppressive mice to improve immunity, thereby shedding light on revealing the molecular mechanism of polysaccharides of traditional Chinese medicines in the future.