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BACKGROUND: Colorectal cancer is among the deadliest cancers in the world. Due to the occurrence of side effects related to current standard therapy, researchers are seeking better alternative treatments. For many years, herbs have been a promising source for discovering therapeutic compounds. Therefore, the primary objective of this research was to examine the distinctive apoptotic and anti-inflammatory properties exhibited by Levisticum officinale Koch (lovage) on HT-29 and Caco-2 cell lines. MATERIALS AND METHODS: The maceration method was used to prepare different extracts (ethanol, dichloromethane, petroleum, and residues) from the plant. These extracts were then tested on two colon cancer cell lines - HT-29 and Caco-2 - using the MTT assay to determine the half-maximal inhibitory concentration (IC50) values. In addition, we evaluated the expression levels of several inflammatory genes (IKKb, IKKa, and REIB) using real-time PCR. We also assessed Cox-2 protein expression using western blot analysis. The western blot was also used to analyze apoptosis-related proteins, including Caspase-3, BAX, and Bcl-2. RESULTS: The dichloromethane extract of Levisticum officin (DELO) exhibited a high cytotoxic effect on Caco-2 and HT-29 cell lines, with IC50 values of 106.0±2 µg/mL in HT-29 cells and 175.3±4 µg/mL in Caco-2 cells after 72 hours. None of the lovage extracts showed a significant cytotoxic effect on non-cancerous cells (3T3 cell line). Furthermore, the group treated with DELO showed a lower expression level of inflammatory genes and COX-2 protein compared to the control group. Notably, treatment with DELO resulted in an increase in Caspase-3 protein and BAX/Bcl-2 ratio in both HT-29 and Caco-2 cells. CONCLUSION: According to this study, DELO has the potential to act as an anti-inflammatory and anti-cancer agent. Further research on the compounds present in DELO and their effect on various signaling pathways could help in the development of new drugs for diseases where inflammation or cells escape from apoptosis play a crucial role.

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Rosa roxburghii Tratt is a rosaceous shrub originating from southwest China (Fu et al. 2020). From September to October 2022, R. roxburghii rot occurred in Guizhou Province, China, within a major R. roxburghii production area covering from 5 ha to 50 ha, with an incidence rate of 10 to 15%. Symptoms manifested as black and brown lesions on the fruit surface, which were concave, soft, foul-smelling, and surrounded by grayish-brown tissue. Three infected R. roxburghii shrubs were randomly collected from each household, placed in transparent plastic bags, and pathogen isolation was conducted in a laboratory. Infected R. roxburghii fruits were surface-sterilized with 0.5% NaOCl for 2 min, rinsed five times with sterile water, and dried. Symptomatic tissues from the margin between necrotic and healthy tissues were cut into 5 × 5 mm pieces, placed onto potato dextrose agar (PDA), and incubated at 28ºC in the dark for 5 days. Hyphal tips of fungi growing from the samples were transferred onto new PDA plates and incubated until they produced conidia. A total of five fungal isolates with similar morphological characteristics were obtained. The colony obtained by single-spore purification was light purple to dark purple with abundant aerial mycelium. Macroconidia were relatively slender with a curve and zero to three septate. Microconidia appeared obovoid to pyriform, with sizes of 5.2 to 17.2 × 2.1 to 3.3 µm (n = 50). The morphological characteristics were consistent with Fusarium annulatum (Yilmaz et al. 2021). Genomic DNA of two representative isolates (Zhaochanglin 1621 and 1622) was extracted using the DN14 cetyltrimethylammonium bromide rapid plant genome extraction kit (Aidlab Biotechnologies Co., Ltd, Beijing). The TEF1 and RPB2 gene were amplified by Polymerase Chain Reaction using primers EF1-983F/EF1-2218R (Rehner et al, 2005), bRPB2-6F/bRPB2-7.1R (Matheny et al, 2002), respectively. All sequences were deposited in GenBank (TEF1, PP236860, PP236861; RPB2, PP767864, PP767865). BLAST searches of the TEF1, and RPB2 sequences revealed the TEF1 sequences had 99.89% (937/938 bp) identity with F. annulatum isolate CBS 258.54; and the RPB2 sequences had 99.86% (737/738 bp) identity to isolate CBS 267.93. In the phylogenetic tree, the isolates (Zhaochanglin 1621 and 1622) clustered with the representative strains of F. annulatum. The morphology and multi-gene phylogenetic analysis indicated that is the isolates were F. annulatum. To complete Koch's postulates, five mature, healthy R. roxburghii fruits were surface disinfected with 1% NaClO solution for 1 min, rinsed with sterile water, and dried at 25℃ for 30 min. A conidial suspension (106 spores/ml) collected from two isolates (Zhaochanglin 1621 and 1622) was sprayed onto R. roxburghii fruits, and the control treatments were sprayed with sterile distilled water. All R. roxburghii fruits were incubated at 25 ºC with 80% relative humidity. The experiment had five replicates. After 7 days of incubation, all the inoculated fruits showed similar symptoms to those initially observed on the originally infected plants. The same pathogen was reisolated and identified by morphological character ization and molecular analysis, fulfilling Koch's postulates. Thus, the pathogen causing rot of R. roxburghii was determined to be F. annulatum (H. Zhang et al, 2024). To our knowledge, this is the first report of F. annulatum causing R. roxburghii rot disease in China. F.annulatum has a wide range of hosts and has been reported to infect a wide range of crops, fruits, and vegetables (Bacon and Nelson 1994). This study lays a foundation for further study and developing disease control methods and the improvement of the economic benefits of R. roxburghii.

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The manuscript disputes the exclusive mono-infectious way of thinking, which presumes that for every infection only one pathogen is responsible and sufficient, when infectious vectors, close contact and reduced immunity meet. In situations involving heavily colonized anatomical sites such an approach often ends in insoluble contradictions. Upon critical reflection and evaluation of 20 years research on spatial organization of vaginal microbiota it is apparent, that in some situations, pathogens may act and operate in permanent, structurally organized consortia, whereas its individual components may be innocuous and innocent, failing to express any pathogenic effect. In these cases, consortia are the true pathogens responsible for many infectious conditions, which usually remain unrecognized as long as improperly diagnosed. The structure of such consortia can be unraveled using ribosomal fluorescence in situ hybridization (FISH). FISH methodology, that not only offers an ex vivo opportunity to recognize bacterial species, but provides unique physical insight into their specific role in the pathogenesis of polymicrobial infections. Ribosomal FISH technique applied to both, women with bacterial vaginosis (BV) and their male partners, has added significantly to our understanding of the pathogenesis of this condition and contributed to appreciating the mechanisms of polymicrobial, community-based infection, potentially leading to therapeutic advances.

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In order to determine the appropriate harvesting period of Carya illinoinensis planted in Nanjing city of China, this study analyzed the phenotypic characteristics and inclusions, including single fruit quality, fruit transverse and vertical diameter, kernel rate, water content, color, respiratory strength, crude fat, soluble sugar, soluble protein, and total phenols, of two cultivars 'Pawnee' and 'Wichita' during September and October, respectively. Results showed that the respiration intensity and IAD values of pecan fruits decreased as the harvest date was delayed. 'Pawnee' fruits exhibited the highest seed kernel fullness, ∆E value, fruit transverse diameter, shape index, kernel yield, crude fat, and total phenolic content in late September and early October, while the quality of 'Wichita' fruits reached its peak in late October. The appropriate harvest period is conducive to the material accumulation of Carya illinoinensis, which is of great practical significance for improving the commodity value of pecans. The optimal harvesting period for 'Pawnee' in Nanjing is from the end of September to the beginning of October, and the optimal harvesting period for 'Wichita' is from mid- to late-October to the end of October.

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Triply Periodic Minimal Surfaces (TPMS), such as Gyroid, are widely accepted for bone tissue engineering due to their interconnected porous structures with tunable properties that enable high surface area to volume ratios, energy absorption, and relative strength. Among these topologies, the Fischer-Koch-S (FKS) has also been suggested for compact bone scaffolds, but few studies have investigated these structures beyond computer simulations. FKS scaffolds have been fabricated in metal and polymer, but to date none have been fabricated in a ceramic used in bone tissue engineering (BTE) scaffolds. This study is the first to fabricate ceramic FKS scaffolds and compare them with the more common Gyroid topology. Results showed that FKS scaffolds were 32% stronger, absorbed 49% more energy, and had only 11% lower permeability than Gyroid scaffolds when manufactured at high porosity (70%). Both FKS and Gyroid scaffolds displayed strength and permeability in the low range of trabecular long bones with high reliability (Weibull failure probability) in the normal direction. Fracture modes were further investigated to explicate the quasi-brittle failure exhibited by both scaffold topologies, exploring stress-strain relationships along with scanning electron microscopy for failure analysis. Considering the physical aspects of successful bone tissue engineering scaffolds, FKS scaffolds appear to be more promising for further study as bone regeneration scaffolds than Gyroid due to their higher compressive strength and reliability, at only a small penalty to permeability. In the context of BTE, FKS scaffolds may be better suited than Gyroids to applications where denser bone and strength is prioritized over permeability, as suggested by earlier simulation studies.

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Intestinal microbiome contains several times of functional genes compared to the host and mediates the generation of multiple metabolic products, and therefore it is called "second genome" for host. Crustaceans rank second among the largest subphylum of aquaculture animals that are considered potentially satisfy global substantial food and nutrition security, among which the Pacific white shrimp (Litopenaeus vannamei) ranks the first in the production. Currently, increasing evidences show that outbreaks of some most devastating diseases in shrimp, including white feces syndrome (WFS) and acute hepatopancreatic necrosis disease (AHPND), are related to intestinal microbiota dysbiosis. Importantly, the intestine microbial composition can be altered by environmental stress, diet, and age. In this review, we overview the progress of intestinal microbiota dysbiosis and WFS or ANPHD in shrimp, and how the microbial composition is altered by external factors. Hence, developing suitable microbial micro-ecological prevention and control strategy to maintain intestinal balance may be a feasible solution to reduce the risk of disease outbreaks. Moreover, we highlight that defining the "healthy intestine microbiota" and evaluating the causality of intestinal microbiota dysbiosis and diseases following the logic of "Microecological Koch's postulates" should be the key goal in future shrimp intestinal field, which help to guide disease diagnosis and prevent disease outbreaks in shrimp farming. KEY POINTS: • Intestinal microbiota dysbiosis is relevant to multiple shrimp diseases. • Microecological Koch's postulates help to evaluate the causality of shrimp diseases.

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Tsukamurella, a group of multi-drug resistant, Gram-positive, aerobic, and partially acid-fast bacteria, are emerging causes of bacterial conjunctivitis and keratitis. However, the pathogenesis of Tsukamurella keratitis is largely unknown. To address this, we used New Zealand White rabbits to develop the first eye infection model and conducted in vitro tests to study the pathogenesis mechanisms of Tsukamurella. There is increasing evidence that biofilms play a significant role in ocular infections, leading us to hypothesize that biofilm formation is crucial for effective Tsukamurella infection. In order to look for potential candidate genes which are important in biofilm formation and Tsukamurella keratitis. We performed genome sequencing of two ocular isolates, T. pulmonis-PW1004 and T. tyrosinosolvens-PW899, to identify potential virulence factors. Through in vitro and in vivo studies, we characterized their biological roles in mediating Tsukamurella keratitis. Our findings confirmed that Tsukamurella is an ocular pathogen by fulfilling Koch's postulates, and using genome sequence data, we identified tmytC, encoding a mycolyltransferase, as a crucial gene in biofilm formation and causing Tsukamurella keratitis in the rabbit model. This is the first report demonstrating the novel role of mycolyltransferase in causing ocular infections. Overall, our findings contribute to a better understanding of Tsukamurella pathogenesis and provide a potential target for treatment. Specific inhibitors targeting TmytC could serve as an effective treatment option for Tsukamurella infections.

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Ramularia mali Videira & Crous is an emerging postharvest pathogen on apple (Malus × domestica Borkh.) in Italy and other apple producing countries (Prencipe et al. 2023). After 3 to 6 months of cold storage at 1 - 2 °C and low oxygen levels of 0.5 - 2 %, lenticels show black-brown speckled dry rot of 1 mm - 5 mm in diameter, without colonizing underlying tissue. The most affected cultivar (cv.) in South Tyrol (northern Italy) is Golden Delicious and postharvest losses due to characteristic lenticel spots range from 10 % to above 50 %. Four symptomatic fruits, originating from two orchards (Latsch/Laces and Bozen/Bolzano; South Tyrol, Italy), respectively, were sampled after cold storage (= ultra-low oxygen; 0.5 % O2 and 1 °C). After surface disinfection with 70 % EtOH for 1 min, sixteen explants from lenticel spots were cultivated on potato dextrose agar (PDA) at 25 °C. Two isolates, morphologically identified as Ramularia sp., were sequenced and showed high identities to R. mali type culture CBS 129581: 100 % and 99.31 % identity for ITS region (MH865432); 94.66 % and 91.41 % for TEF-1α (KJ504693); 97.22% and 97.40% for RpbII (KJ504649). Isolates were cultivated at 25 °C for 2 weeks and conidia were harvested with 3.0 mL 0.05 % Tween®20. Inoculation was performed in triplicate on 5-month cold stored fruits cv. Golden Delicious. After surface disinfection for 1 min with cotton swabs, which were immersed in 70 % EtOH, 10 µL spore suspension of each isolate (8.50 × 107 spores mL-1 in 0.05 % Tween®20) were injected horizontally beneath the epidermis with a syringe (Hamilton® model 710N). Also, a mixture of both isolates was used. Controls were carried out with 0.05 % Tween®20 only. Apples were stored either at 9 °C in the dark or at 1°C and 0.5 % oxygen for 4 months. First symptoms were observed for both spore concentrations after 2 weeks at 9 °C. The injection pathway changed to a brownish color, whereas the control did not show any change (Fig. 1). Final evaluation was carried out after 4 months, but the fruits did not show further symptom development. Fruits stored at 1°C for 5 months were simultaneously evaluated, confirming that the pathogen invaded the tissue surrounding the injection site, without penetrating deeper into the fruit flesh. (Fig. 2). Reisolation from artificially infected apples was successfully achieved, and sequence analysis was performed on the DNA extracts from the obtained isolates. Concatenated sequences of ITS (deposited to GenBank under the accession numbers: PP439643 -PP439647), TEF-1α (PP480231-PP480235), and RbpII (PP480226-PP480230) were subjected to multi-locus sequence analysis. References sequences of R. nyssicola CBS 127665, R. collo-cygni CBS 101181, R. vizellae CBS 115981, R. eucalypti CBS 120726, R. hydrangeae-macrophyllae CBS 122272, R. glennii CBS 129441 and R. mali CBS 129581 included and aligned by the CLUSTALW algorithm within the software Geneious® 11.1.5 (Biomatters Inc., New Zealand). Phylogeny was reconstructed with MEGAX (Version 10.2.6) (Kumar et al. 2018) based on the Maximum Likelihood (ML) algorithm (Fig. 3). Isolates from artificially infected fruit clustered with the R. mali type culture. Although Gianetti et al. (2012) and Lindner (2013), respectively, first described Ramularia sp. as a postharvest pathogen on apple, the present study demonstrated the reproduction of lenticel dry rot symptoms by R. mali.

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BACKGROUND: Cobweb disease is a fungal disease that commonly affects the cultivation and production of edible mushrooms, leading to serious yield and economic losses. It is considered a major fungal disease in the realm of edible mushrooms. The symptoms of cobweb disease were found during the cultivation of Lyophyllum decastes. This study aimed to identify the causative pathogen of cobweb disease and evaluate effective fungicides, providing valuable insights for field control and management of L. decastes cobweb disease. RESULTS: The causal agent of cobweb disease was isolated from samples infected and identified as Cladobotryum mycophilum based on morphological and cultural characteristics, as well as multi-locus phylogeny analysis (ITS, RPB1, RPB2, and TEF1-α). Pathogenicity tests further confirmed C. mycophilum as the responsible pathogen for this condition. Among the selected fungicides, Prochloraz-manganese chloride complex, Trifloxystrobin, tebuconazole, and Difenoconazole exhibited significant inhibitory effects on the pathogen's mycelium, with EC50 values of 0.076 µg/mL, 0.173 µg/mL, and 0.364 µg/mL, respectively. These fungicides can serve as references for future field control of cobweb disease in L. decastes. CONCLUSION: This study is the first report of C. mycophilum as the causing agent of cobweb disease in L. decastes in China. Notably, Prochloraz-manganese chloride complex demonstrated the strongest inhibitory efficacy against C. mycophilum.

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The germ theory states that pathogenic microorganisms are responsible for causing infectious diseases. The theory is inherently microbe-centric and does not account for variability in disease severity among individuals and asymptomatic carriership-two phenomena indicating an important role for host variability in infection outcome. The basic tenet of the germ theory was recently challenged, and a radically host-centric paradigm referred to as the "full-blown host theory" was proposed. According to this view, the pathogen is reduced to a passive environmental trigger, and the development of disease is instead due to pre-existing immunodeficiencies of the host. Here, we consider the factors that determine disease severity using established knowledge concerning evolutionary biology, microbial pathogenesis, and host-pathogen interactions. We note that the available data support a noncentric view that recognizes key roles for both the causative microbe and the host in dictating infection outcome.

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This recommendation of the Commission for Hospital Hygiene and Infection Prevention (KRINKO) addresses not only hospitals, but also outpatient health care facilities and compiles current evidence. The following criteria are the basis for the indications for cleaning and disinfection: Infectious bioburden and tenacity of potential pathogens on surfaces and their transmission routes, influence of disinfecting surface cleaning on the rate of nosocomial infections, interruption of cross infections due to multidrug-resistant organisms, and outbreak control by disinfecting cleaning within bundles. The criteria for the selection of disinfectants are determined by the requirements for effectiveness, the efficacy spectrum, the compatibility for humans and the environment, as well as the risk potential for the development of tolerance and resistance. Detailed instructions on the organization and implementation of cleaning and disinfection measures, including structural and equipment requirements, serve as the basis for their implementation. Since the agents for surface disinfection and disinfecting surface cleaning have been classified as biocides in Europe since 2013, the regulatory consequences are explained. As possible addition to surface disinfection, probiotic cleaning, is pointed out. In an informative appendix (only in German), the pathogen characteristics for their acquisition of surfaces, such as tenacity, infectious dose and biofilm formation, and the toxicological and ecotoxicological characteristics of microbicidal agents as the basis for their selection are explained, and methods for the evaluation of the resulting quality of cleaning or disinfecting surface cleaning are presented.

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In 2015 and 2016, two Barramundi (Lates calcarifer) farms in Singapore reported a disease outbreak characterized by lethargic behavior, pronounced inappetence, generalized skin lesions, erosions of the fins and tail, and ultimately high mortality in their fish. Next-generation sequencing and PCR confirmed presence of a novel virus belonging to the Alloherpesviridae family, Lates calcarifer herpesvirus (LCHV), which was subsequently isolated and cultured. We characterize, for the first time, the complete genome of two cultured LCHV isolates. The genome contains a long unique region of approximately 105,000 bp flanked by terminal repeats of approximately 24,800 bp, of which the first 8.2 kb do not show any similarity to described genomes in the Alloherpesviridae family. The two cultured isolates share 89% nucleotide identity, and their closest relatives are the viruses belonging to the genus Ictalurivirus. Experimental infections using one of the cultured LCHV isolates resulted in identical clinical signs as originally described in the index farm, both in intraperitoneal-injection infected fish and cohabitant fish, with mortality in both groups. Histopathological analysis showed pronounced abnormalities in the gills. Virus culture and PCR analysis confirmed the replication of LCHV in the infected fish, and thus Koch's postulates were fulfilled.

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INTRODUCTION: The optimal slow pathway (SP) ablation site in cases with an inferiorly located His bundle (HIS) remains unclear. METHODS AND RESULTS: In 45 patients with atrioventricular nodal reentrant tachycardia, the relationship between the HIS location and successful SP ablation site was assessed in electroanatomical maps. We assessed the location of the SP ablation site relative to the bottom of the coronary sinus ostium in the superior-to-inferior (SPSI), anterior-to-posterior (SPAP), and right-to-left (SPRL) directions. The HIS location was assessed in the same manner. The HIS location in the superior-to-inferior direction (HISSI), SPSI, SPAP, and SPRL were 17.7 ± 6.4, 1.7 ± 6.4, 13.6 ± 12.3, and -1.0 ± 13.0 mm, respectively. The HISSI was positively correlated with SPSI (R2 = 0.62; P < .01) and SPAP (R2 = 0.22; P < .01), whereas it was not correlated with SPRL (R2 = 0.01; P = .65). The distance between the HIS and SP ablation site was 17.7 ± 6.4 mm and was not affected by the location of HIS. The ratio of the amplitudes of atrial and ventricular potential recorded at the SP ablation site did not differ between the high HIS group (HISSI ≥ 13 mm) and low HIS group (HISSI < 13 mm) (0.10 ± 0.06 vs. 0.10 ± 0.06; P = .38). CONCLUSION: In cases with an inferiorly located HIS, SP ablation should be performed at a lower and more posterior site than in typical cases.

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Cytotoxicity-guided purification of Juniperus polycarpos K. Koch leaves (Cupressaceae) led to the isolation of a new labdane diterpenoid, 3-(acetyloxy)-acetylisocupressic acid (1), together with isocupressic acid (2), 3,4-dimethoxycinnamoyl alcohol (3) and deoxypodophyllotoxin (4). The chemical structures of 1-4 were established by detailed 1D and 2D NMR, HRFAB-MS and LRESI-MS, as well as by comparing the spectral data with those reported in the literature. Compound 1 was ineffective against HepG2 cells and protease enzyme, while 2 showed potent cytotoxicity against HepG2 cells (IC50 of 3.73 µg/mL) compared to cisplatin (IC50 of 12.65 µg/mL). Computational analyses with CDK1 protein (a prominent protein in the cell cycle of HepG2 cells) revealed the binding affinity of 2 (-31.86 kcal/mol) was better than 1 (-19.70 kcal/mol) because the acetoxy groups did not allow binding deeply to the ATP binding site. Compounds 2 and 4 moderately inhibited the protease activity (IC50 = 52.7 and 63.0 µg/mL, respectively). Further in vitro and in vivo studies on the plant are strongly recommended.

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Leaf-blight disease caused by the Fusarium oxysporum is an emerging problem in Dendrobium chrysotoxum production in China. Symptoms of leaf blight were observed on seedlings of D. chrysotoxum cultivated in a nursery in Ruili City, Yunnan Province, China. In this study, we isolated the Fusarium sp. associated with leaf-blight disease of D. chrysotoxum from the diseased seedlings. A pathogenicity test was performed to fulfill Koch's postulates to confirm the pathogenicity of isolated strains and identified using morphological and molecular techniques. The results revealed that all four isolated Fusarium sp. isolates (DHRL-01~04) produced typical blight symptoms followed by marginal necrosis of leaves on the D. chrysotoxum plants. On the PDA medium, the fungal colony appeared as a white to purplish color with cottony mycelium growth. Microconidia are oval-shaped, whereas macroconidia are sickle-shaped, tapering at both ends with 2-4 septations. The phylogenetic trees were construed based on internal transcribed spacer (ITS), translation elongation factor (EF-1α), and RNA polymerase subunit genes RPB1 and RPB2 genes, respectively, and blasted against the NCBI database for species confirmation. Based on the NCBI database's blast results, the isolates showed that more than 99% identify with Fusarium oxysporum. To our knowledge, this is the first comprehensive report on the identification of Fusarium oxysporum as the causal agent of Dendrobium chrysotoxum leaf blight in Yunnan Province, China, based on morphological and molecular characteristics.

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Spider mites (Acari: Tetranychidae) are polyphagous pests of economic importance in agriculture, among which the two-spotted spider mite Tetranychus urticae Koch has spread widely worldwide as an invasive species, posing a serious threat to fruit tree production in China, including Beijing. The hawthorn spider mite, Amphitetranychus viennensis Zacher, is also a worldwide pest of fruit trees and woody ornamental plants. The cassava mite, Tetranychus truncatus Ehara, is mainly found in Asian countries, including China, Korea and Japan, and mainly affects fruit trees and agricultural crops. These three species of spider mites are widespread and serious fruit tree pests in Beijing. Rapid and accurate identification of spider mites is essential for effective pest and plant quarantine in Beijing orchard fields. The identification of spider mite species is difficult due to their limited morphological characteristics. Although the identification of insect and mite species based on PCR and real-time polymerase chain reaction TaqMan is becoming increasingly common, DNA extraction is difficult, expensive and time-consuming due to the minute size of spider mites. Therefore, the objective of this study was to establish a direct multiplex PCR method for the simultaneous identification of three common species of spider mites in orchards, A. viennensis, T. truncatus and T. urticae, to provide technical support for the differentiation of spider mite species and phytosanitary measures in orchards in Beijing. Based on the mitochondrial cytochrome c oxidase subunit I (COI) of the two-spotted spider mite and the cassava mite and the 18S gene sequence of the hawthorn spider mite as the amplification target, three pairs of specific primers were designed, and the primer concentrations were optimized to establish a direct multiplex PCR system for the rapid and accurate discrimination of the three spider mites without the need for DNA extraction and purification. The method showed a high sensitivity of 0.047 ng for T. truncatus and T. urticae DNA and 0.0002 ng for A. viennensis. This method eliminates the DNA extraction and sequencing procedures of spider mite samples, offers a possibility for rapid monitoring of multiple spider mites in an integrated microarray laboratory system, reducing the time and cost of leaf mite identification and quarantine monitoring in the field.

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Background: Leaf spot disease severely impacts Ginkgo biloba (G. biloba) yield and quality. While microbial agents offer effective and non-toxic biological control for plant diseases, research on controlling leaf spot disease in G. biloba is notably scarce. Methods: The pathogenic fungi were isolated and purified from diseased and healthy leaves of G. biloba, Subsequent examinations included morphological observations and molecular identification via PCR techniques. A phylogenetic tree was constructed to facilitate the analysis of these pathogenic fungi, and Koch's postulates were subsequently employed to reaffirm their pathogenic nature. The antagonistic experiment was employed to select biocontrol bacteria, and subsequently, the isolated biocontrol bacteria and pathogenic fungi were inoculated onto healthy leaves to assess the inhibitory effects of the biocontrol bacteria. Results: Two pathologies responsible for the leaf spot disease on G. biloba were identified as Botryosphaeria dothidea and Neofusicoccum parvum via the analysis of phylogenetic tree and the application of Koch's Postulates. Additionally, we isolated two strains of biocontrol bacteria, namely Bacillus velezensis and Bacillus amyloliquefaciens. Their average inhibitory zones were measured at 4.78 cm and 3.46 cm, respectively. The inhibition zone of B. velezensis against N. parvum was 4 cm. B. velezensis showed a stronger inhibitory effect compared to B. amyloliquefaciens on the development of lesions caused by B. dothidea via leaf culture experiment. Conclusion: This research reports, for the first time, the presence of B. dothidea as a pathogenic fungus affecting G. biloba. Moreover, the biocontrol bacteria, B. velezensis and B. amyloliquefaciens, exhibited the capability to effectively inhibit the growth and reproduction of B. dothidea, indicating their promising potential as environmentally friendly biocontrol resources.

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Auricularia cornea is an important edible mushroom crop in China but the occurrence of cobweb disease has cause significance economic loss in its production. The rate of disease occurrence is 16.65% all over the country. In the present study, a new pathogen Hypomyces cornea sp. nov. was found to cause the cobweb disease. In July 2021, three strains of fungal pathogen were isolated from infected fruiting bodies and identified as H. cornea based on morphological studies and molecular phylogenetic analysis of internal transcribed spacer (ITS) of nuclear ribosomal DNA, mitochondrial large subunit (LSU) of rRNA and the partial translation elongation factor 1-alpha genes. The representative isolates of the pathogenic Hypomyces species used to perform pathogenicity test with spore suspension that caused similar symptoms as those observed in the cultivated field, and same pathogens could be re-isolated, which fulfill Koch's postulates. The typical biological characterization was examined of the serious pathogen to determine its favorable growth conditions, including suitable temperature, pH, carbon, nitrogen sources and light conditions. The findings revealed an optimum temperature of 25 °C, pH of 6, and soluble starch and peptone as the preferred carbon and nitrogen sources, respectively. The hyphal growth inhibition method was used for primary in vitro screening test of seven common fungicides, and the most suitable fungicide is Prochloraz manganese chloride complex, the EC50 values of cobweb pathogen and mushrooms were 0.085 µg/mL and 2.452 µg/mL, respectively. The results of our research provide an evidence-based basis for the effective prevention and treatment of A. cornea cobweb disease.

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