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Scientific Reports Jun 2024Sugarcane smut is the most damaging disease that is present almost across the globe, causing mild to severe yield losses depending upon the cultivar types, pathogen...
Sugarcane smut is the most damaging disease that is present almost across the globe, causing mild to severe yield losses depending upon the cultivar types, pathogen races and climatic conditions. Cultivation of smut-resistant cultivars is the most feasible and economical option to mitigate its damages. Previous investigations revealed that there is a scarcity of information on early detection and effective strategies to suppress etiological agents of smut disease due to the characteristics overlapping within species complexes. In this study, 104 sugarcane cultivars were screened by artificial inoculation with homogenate of all possible pathogen races of Sporisorium scitamineum during two consecutive growing seasons. The logistic smut growth pattern and the disease intrinsic rate were recorded by disease growth curve. Variable levels of disease incidence i.e., ranging from 0 to 54.10% were observed among these sugarcane cultivars. Besides, pathogen DNA in plant shoots of all the cultivars was successfully amplified by PCR method using smut-specific primers except 26 cultivars which showed an immune reaction in the field trial. Furthermore, the plant germination and tillering of susceptible sugarcane cultivars were greatly influenced by pathogen inoculation. In susceptible cultivars, S. scitamineum caused a significant reduction in setts germination, coupled with profuse tillering, resulting in fewer millable canes. Correlation analysis demonstrated that there was a positive relationship between reduction in setts germination and increase in the number of tillers. The present study would be helpful for the evaluation of smut resistance in a wide range of sugarcane germplasm, especially from the aspects of setts germination and tillers formation, and it also screened out several excellent germplasm for potential application in sugarcane breeding.
Topics: Saccharum; Plant Diseases; Germination; Disease Resistance; Ustilaginales
PubMed: 38918529
DOI: 10.1038/s41598-024-64810-1 -
Nature Communications Jun 2024Anaerobic digestion of organic waste into methane and carbon dioxide (biogas) is carried out by complex microbial communities. Here, we use full-length 16S rRNA gene...
Anaerobic digestion of organic waste into methane and carbon dioxide (biogas) is carried out by complex microbial communities. Here, we use full-length 16S rRNA gene sequencing of 285 full-scale anaerobic digesters (ADs) to expand our knowledge about diversity and function of the bacteria and archaea in ADs worldwide. The sequences are processed into full-length 16S rRNA amplicon sequence variants (FL-ASVs) and are used to expand the MiDAS 4 database for bacteria and archaea in wastewater treatment systems, creating MiDAS 5. The expansion of the MiDAS database increases the coverage for bacteria and archaea in ADs worldwide, leading to improved genus- and species-level classification. Using MiDAS 5, we carry out an amplicon-based, global-scale microbial community profiling of the sampled ADs using three common sets of primers targeting different regions of the 16S rRNA gene in bacteria and/or archaea. We reveal how environmental conditions and biogeography shape the AD microbiota. We also identify core and conditionally rare or abundant taxa, encompassing 692 genera and 1013 species. These represent 84-99% and 18-61% of the accumulated read abundance, respectively, across samples depending on the amplicon primers used. Finally, we examine the global diversity of functional groups with known importance for the anaerobic digestion process.
Topics: Archaea; RNA, Ribosomal, 16S; Anaerobiosis; Bacteria; Microbiota; Biodiversity; Phylogeny; Wastewater; Bioreactors; Methane; Sequence Analysis, DNA
PubMed: 38918384
DOI: 10.1038/s41467-024-49641-y -
Marine Environmental Research Jun 2024Marine phytoplankton are widely used to monitor the state of the water column due to their rapid changes in response to environmental conditions. In this study, we aimed...
Marine phytoplankton are widely used to monitor the state of the water column due to their rapid changes in response to environmental conditions. In this study, we aimed to investigate the coastal phytoplankton assemblages, including bloom-forming species using high-throughput sequencing of 18S rRNA genes targeting the V4 region and their relationship with environmental variables along the Istanbul coasts of the Sea of Marmara. A total of 118 genera belonging to six phyla were detected. Among them, Dinoflagellata (36) and Bacillariophyta (26) were represented with the highest number of genera. According to the relative abundance of DNA reads, the most abundant taxa were Dinoflagellata_phylum (18.1%), Emiliania (8.4%), Biecheleria (8.4), and Noctiluca (8.1%). The ANOSIM test showed that there was a significant temporal difference in the assemblages, while the driving environmental factors were pH, water temperature, and salinity. According to the TRIX index, the trophic state of the coasts was highly mesotrophic and eutrophic. In addition, 45 bloom-forming and HAB taxa were detected and two species of Noctiluca and Emiliania, which frequently cause blooms in the area, were recorded in high abundance. Our results provide insight into the phytoplankton assemblages along the urbanized coastlines by analysing the V4 region of 18S rRNA. This data can support future studies that use both traditional methods and metabarcoding, employing various primers and targeting different genes and regions.
PubMed: 38917660
DOI: 10.1016/j.marenvres.2024.106623 -
Plant Disease Jun 2024The Chinese quince (Chaenomeles sinensis (Thouin) Koehne), belongs to the Rosaceae family, is widely distributed throughout Asia, including Republic of Korea. It is used...
The Chinese quince (Chaenomeles sinensis (Thouin) Koehne), belongs to the Rosaceae family, is widely distributed throughout Asia, including Republic of Korea. It is used as a traditional treatment for asthma, common cold, and dry pharynx. Numerous recent pharmacological studies on antiinfluenza, antioxidant, and antidiabetic properties have confirmed the medicinal properties of the Chinese quince fruit (Chun et al., 2012). In March 2022, leaf spots on Chinese quince, resulting in defoliation, were observed in Andong, Gyeongsangbuk Province, Korea (Fig. 1A). The disease symptoms are dark brown spots on leaves. Later, the chlorophyll is lost, causing the entire leaf to become wilted and fell off (Fig. 1B). To identify the pathogen, symptomatic leaves were brought to the laboratory, cut into small pieces, and surface-disinfected in 70% ethanol for 15 s and rinsed with sterile distilled water (SDW). The specimens were then treated with 1% NaOCl for 15 s, followed by rinsing with SDW. Thus, surface-disinfected tissues were placed onto potato dextrose agar (PDA) plates and incubated at 25°C for 7 d. A total of four isolates were obtained from the infected leaves. The colonies were transferred onto freshly prepared PDA plates by the single spore method for further purification. GYUN-10746 isolate was selected as the representative strain among the four isolates and deposited in the Korean Agricultural Culture Collection (KACC 410367). They initially produced white mycelia, which turned dark brown or pale brown at the center and beige at the periphery after 7 d (Fig. 1C and D). Conidiophores were pyriform, sometimes ovoid, or ellipsoidal and brown, measuring 30.8 ± 0.49 × 12.9 ± 0.26 µm (length × width) (n=100) (Fig. 1E). The morphological characteristics were consistent with those of Alternaria alternata (Woudenberg et al. 2015). For molecular identification, DNA was amplified using the following primers: ITS1/ITS4 (White et al. 1990), EF1-728F/EF1-986R (Carbone et al. 1999), Gpd-R/Gpd-F (Berbee et al. 1999), Alt a1-F/Alt a1-R (Hong et al. 2005) and rpb2F/rpb2R (Liu et al. 1999) by PCR. DNA sequences from all 4 isolates (GYUN-10746, GYUN-11193, GYUN-11194 and GYUN-11195) were identical. The ITS (OP594615), TEF1-α (OR327062), GAPDH (OR372157), Alt a 1 (OR327061), and RPB2 (OR352741) sequences from the representative isolate GYUN-10746 were 100% identical to those of previously identified A. alternate isolates. A phylogenetic tree was constructed using sequences of ITS, TEF1-α, GAPDH, Alt a l, and RPB2 to illustrate their relationship with A. alternata and related Alternaria species (Fig. 2). For the pathogenicity test, healthy Chinese quince branch containing leaves were inoculated with 7-day-old mycelial plugs of A. alternata, while leaves on a branch inoculated with PDA plugs alone served as a control group. Thus inoculated branches were incubated at 25°C for 7 d. Disease symptoms were developed on leaves of the branches inoculated with mycelial plugs of the fungal pathogen (Fig. 1F), while no symptoms developed on control group. The resulting leaf spots resembled those on the original infected plants. To confirm Koch's postulates, the pathogen was re-isolated from inoculated leaves with identical morphological and molecular characteristics. To the best of our knowledge, this is the first report of leaf spot caused by A. alternata in C. sinensis in Korea. The identification of the pathogen may provide pertinent information for the development of disease controlling strategies.
PubMed: 38916907
DOI: 10.1094/PDIS-05-24-0984-PDN -
Plant Disease Jun 2024Cigar tobacco (Nicotiana tabacum L.) is widely planted in Yunnan, which is becoming an important economic crop in China. In March 2023, root rot of cigar tobacco (cv....
Cigar tobacco (Nicotiana tabacum L.) is widely planted in Yunnan, which is becoming an important economic crop in China. In March 2023, root rot of cigar tobacco (cv. Yunxue 38) was observed in Baoshan (98°51'E, 24°58'N), and in July 2022 root rot of tobacco (cv. Yunyan 87) was observed in Dali (99°54'E, 26°30'N), Yunnan Province, China. The average disease incidences surveyed in the fields reached 10%. At the early stage, the bottom leaves showed wilting and turned yellow, and the roots became brown. Following the disease development, the color of roots turned to dark brown and ultimately necrosis. To isolate the causal agent, small pieces (5×5 mm) of diseased root from 6 symptomatic plant samples (three samples of cv. Yunxue 38 and three samples of cv. Yunyan 87) were cut. Pieces were surface-sterilized by dipping in 75% ethanol for 30 s, rinsed three times with sterile distilled water, then transferred to potato dextrose agar (PDA) medium and incubated at 28°C in the dark. Six fungal isolates cultured for 14 days were obtained. They were morphologically similar, so a representative isolate was selected for the following experiment. The colonies grew slowly on PDA, and their color were light pink initially, then changed to amaranth. Hyphae were hyaline and septate. Microconidia were hardly produced on PDA plates. After 14 days of culture on V8 juice agar, the colonies showed white aerial mycelia, and ellipsoidal and transparent conidia were observed, which measured 6.5 to 8.3 × 3.4 to 5.0 μm (n=20). Also, the pycnidia were measured 150 to 220 μm, that were subglobose in dark brown with brown setae. These morphological characteristics of 22DL91 were identical to S. terrestris (Boerema et al. 2004). For molecular identification, DNA was extracted and the PCR products of ITS region and polymerase II second largest subunit (RPB2), amplified with the primers ITS1/ITS4 and RPB2-5F/RPB2-7cR, were sequenced. By BLASTn analysis, the obtained ITS sequences showed 100% homology and the RPB2 sequences showed 95% homology with S. terrestris strains in GenBank (accession ON006851 and OM417590). The sequences were deposited in NCBI with accession numbers OR539491 (ITS) and OR554276 (RPB2), respectively. Based on the morphology and phylogenetic analysis, the isolate was 22DL91 identified as S. terrestris. Pathogenicity was evaluated on 50-day-old cigar tobacco seedlings (cv. Yunxue 38) and tobacco seedlings (cv. Yunyan 87). Ten plants were inoculated with 20 mL of conidial suspension of 105 conidia/mL poured onto the roots and ten control seedlings dipped in sterile water as controls (Luo et al. 2023). After 14 days, all inoculated seedlings showed the symptoms with leaves yellowing and root rot, whereas the control seedlings had no symptoms. Moreover, the fungus S. terrestris was reisolated from the infected roots, fulfilling Koch's postulates. This fungus was previously known to cause pink root on garlic in China (Zhang et al. 2019). To our knowledge, this is the first report of S. terrestris causing root rot of Nicotiana tabacum in China. Therefore, this finding will provide valuable information for prevention and management of root rot on tobacco.
PubMed: 38916905
DOI: 10.1094/PDIS-04-24-0721-PDN -
Plant Disease Jun 2024In August 2023, butterhead lettuce ( L.) presented wilting, chlorosis, and about 2 cm of reddish-tan internal discoloration in the crown from a commercial greenhouse in...
In August 2023, butterhead lettuce ( L.) presented wilting, chlorosis, and about 2 cm of reddish-tan internal discoloration in the crown from a commercial greenhouse in Orange County, North Carolina. Plant collapse beginning with the outer leaves near the soil surface was observed with 25% disease incidence. Symptomatic lettuce plants were submitted to North Carolina State University's Plant Disease and Insect Clinic. Vascular tissue from symptomatic crowns were cut into pieces, and surface-sterilized in 10% NaOCl for two minutes. The tissue was rinsed in sterile deionized water three times, blotted dry, and placed on acidified potato dextrose agar (APDA). Three isolates, each from a different symptomatic plant, were transferred to APDA and Spezieller Nährstoffarmer agar (SNA) with pieces of sterile filter paper on the surface of the SNA media and incubated for 14 days at 23°C in the dark. Each isolate produced micro and macroconidia consistent with the morphological description of Schlechtendahl emend. Snyder & Hansen (Leslie and Summerell 2006). DNA was extracted from 15-day-old fungal colonies grown on APDA media using the DNeasy Plant Mini Kit (Qiagen, Germantown, MD, U.S.A.). The intergenic spacer locus was amplified using two primer pairs, iNL11/CNSa and iCNS1/NLa, and sequences were aligned together to form a single contig (O'Donnell et al., 2009). Primers EF1/EF2 were used to amplify the elongation factor 1-alpha region (O'Donnell et al., 1998). Each isolate was deposited into GenBank with accession numbers PP216479, PP216480, PP216481, PP235836, PP235837, and PP235838. Individual isolates revealed a 100% query cover and identity match with sequences of f. sp. (FOL) and >99% identity with CBS 144134 type material accessions in GenBank using BLASTn. A comparison with previously described lettuce isolates showed a homologous match with FOL race 1 isolates from California (MH412701), Arizona (DQ837658), and Greece (OQ466116), and race 4 isolates from Italy (MK801787) and Spain (OP903519). Each isolate was verified as FOL using specific primers FLA0001F/FLA0001R for FOL based on sequence tagged site markers designed by Shimazu et al. (2005). To confirm Koch's postulates, fifteen 21-day-old lettuce cv. Red Tide plants were inoculated with FOL (isolate FOLNC_660). During transplanting, lettuce roots were submerged in a 1 × 10 conidia/mL suspension for five minutes, following an inoculation protocol from Schmale and Gordon (2003). The lettuce plants were placed separately in 8.9 × 8.3 cm pots containing potting soil and maintained in a greenhouse with 31°C daytime and 25°C nighttime temperature, relative humidity of 60%, and 12-hour photoperiod. After 15 days, 80% and 86.7% of infected plants exhibited wilting, chlorosis, and vascular discoloration. The fifteen control plants remained symptomless for both experimental runs. FOL was recovered from the vascular tissue of all symptomatic plants. To our knowledge, this constitutes the first report of FOL infecting lettuce in North Carolina. Fusarium wilt of lettuce has been reported in California (Hubbard and Gerik 1993), Arizona (Matheron and Koike 2003), and most recently in Florida (Murray et al., 2020). The presence of FOL in North Carolina may result in significant crop loss for commercial growers. One of the most effective management strategies is to plant lettuce cultivars that are resistant against FOL.
PubMed: 38916903
DOI: 10.1094/PDIS-02-24-0364-PDN -
International Journal of... Apr 2024Environmental mycobacteria are involved in several infections ranging from lung to skin infections. In Côte d'Ivoire, apart from Mycobacterium ulcerans and...
BACKGROUND
Environmental mycobacteria are involved in several infections ranging from lung to skin infections. In Côte d'Ivoire, apart from Mycobacterium ulcerans and Mycobacterium tuberculosis, little information exists on other species. The culture of these species, a real challenge, especially in developing countries like Cote d'Ivoire, limits their identification. However, there are reports in literature of infections caused by these mycobacteria, and few species have never been described in human or animal infections. These are difficult cases to treat because of their resistance to most antituberculosis antibiotics. The aim of our work was to study the diversity of potentially pathogenic mycobacterial species in wastewater drainage channels in different townships and in two hospital effluents in the city of Abidjan.
METHODS
Wastewater samples were cultured, followed by conventional polymerase chain reaction (PCR) targeting mycobacterial 16S ribonucleic acid (16S RNA) using PA/MSHA primers. 16 S RNA identified were sequenced by Sanger techniques. Sequences obtained were analyzed, and a phylogenic tree was built.
RESULTS
Fast-growing mycobacteria, including Mycobacterium fortuitum, Mycobacterium phocaicum, Mycobacterium sp., and others presence, were confirmed both by culture and molecular techniques. M. fortuitum strain was the same in effluents of the Treichville University Hospital and in the wastewater of the township of Koumassi. New species never isolated in Côte d'Ivoire, such as M. phocaicum, have been identified in wastewater of the township of Yopougon.
CONCLUSION
This study showed that the sewer network in the city of Abidjan is colonized by both potentially pathogenic mycobacteria and saprophytic environmental mycobacteria.
Topics: Cote d'Ivoire; Phylogeny; RNA, Ribosomal, 16S; Humans; Nontuberculous Mycobacteria; Wastewater; Polymerase Chain Reaction; DNA, Bacterial; Mycobacterium
PubMed: 38916386
DOI: 10.4103/ijmy.ijmy_96_24 -
Methods in Molecular Biology (Clifton,... 2024Single-cell RNA sequencing supports the isolation of individual cells and barcoding of cDNA, specific to each cell of origin. Subsequent sequencing of the generated...
Single-cell RNA sequencing supports the isolation of individual cells and barcoding of cDNA, specific to each cell of origin. Subsequent sequencing of the generated library yields both the gene expression sequences and the cellular barcode, allowing distinction of gene expression patterns across individual cells. The 10X Genomics 3' HT assay uses a droplet-based method to isolate individual cells within oil emulsions, combined with a gel bead coated in uniquely barcoded primers, specific to each bead. The high-throughput, HT, assay is similar to its predecessor (3' v3.1) in reaction chemistry but utilizes (a) higher numbers of cellular barcodes, (b) a new, proprietary chip designed to target up to 60,000 cells per lane, and (c) captures up to 16 samples per run. The 3' HT assay supports whole cells and nuclei as input, with an approximate 60% capture rate. Here we describe the methods for sample quality control (QC) assays, loading and operation of the Chromium X instrument for cell capture, and cDNA synthesis and library preparation for downstream Illumina sequencing.
Topics: Humans; High-Throughput Nucleotide Sequencing; Genomics; Gene Library; Single-Cell Analysis; Sequence Analysis, RNA; Gene Expression Profiling; DNA, Complementary
PubMed: 38907921
DOI: 10.1007/978-1-0716-3918-4_15 -
Plant Disease Jun 2024Coptis (Coptis chinensis) belongs to the Ranunculaceae family, the rhizomes used in traditional Chinese medicine. Since 2021, an uncommon stem and leaf wilt disease,...
Coptis (Coptis chinensis) belongs to the Ranunculaceae family, the rhizomes used in traditional Chinese medicine. Since 2021, an uncommon stem and leaf wilt disease, with an average disease incidence of 70%~90%, has been observed in Guangdong and Guangxi provinces. The early wilt symptoms were observed on older leaves and stems, and the whole seedling wilted and died. The rhizome of the diseased seedlings changed in color, became necrotic, and rotted. Symptomatic roots and stems were surface-sterilized with 70% ethanol for 30 s, followed by 0.2% NaClO for 2-3 min, rinsed in sterile water three times, and then placed on potato dextrose agar (PDA) at 25℃for 14 days. Fungal growth was observed, and six isolates with similar morphology were obtained. The 14-day-old colonies on PDA were buff with few aerial hyphae and slimy surfaces. Aerial hyphae were sparse with simple or branched conidiophores. Conidia were hyaline, smooth, ovoid, septate or aseptate, and 5.77 to 9.53 × 2.15 to 3.32 µm (n = 50). Three of the six isolates were subjected to further analysis. The genomic DNA of three isolates (CCF1-1, CCF1-2, CCF1-3) was extracted using Axygen MAG-FRAG- I-50 (Axygen Bio-Tek) for molecular identification. Partial sequences of the internal transcribed spacer of rDNA (ITS) and large subunit rDNA (LSU) were amplified using the primers ITS1/4 and LR5F/LROR, respectively (Vilgalys and Hester 1990). Their sequences were aligned by MEGA X (Kumar et al., 2018), and the sequences of each region showed 100% sequence similarity among our isolates. A BLAST search of ITS and LSU sequences (accession nos. ON377369, ON428244) showed that both regions had the highest nucleotide similarities (99.43 to 99.89%) to the Plectosphaerella cucumerina strains. Based on morphological and molecular analyses, the isolates were identified as P. cucumerina (Palm et al. 1995). The pathogenicity of our isolates CCF1-1, CCF1-2, CCF1-3 was tested on ten 2-month-old healthy seedlings of coptis, respectively. For the seedlings, 30 ml of fungal conidial suspension (1×106 conidia/ml) or sterile water, as control, were poured into their root area. Conidia suspension were prepared from 14-day-old cultures on PDA by eluting with sterilized water. The seedlings were incubated at 25°C and 75% relative humidity under a 12-h/12-h light/dark cycle. The test was repeated three times. After 20 days, only seedlings inoculated with P. cucumerina exhibited symptoms similar to those diseased seedlings in the field. The control seedling had no symptoms. The morphologically similar fungus was re-isolated from the tested seedlings, thus fulfilling Koch's postulates. Based on molecular, morphological, and pathogenic properties, P. cucumerina is the causal fungal pathogen of coptis wilt disease. Previously, P. cucumerina has been related to wilt disease in strawberry and Chinese cabbage (Yang et al. 2023; Gao et al. 2022), but to our knowledge, this is the first report of P. cucumerina causing wilt disease on coptis in China. Coptis wilt disease tends to occur in a warm and rainy environment, and strengthening the detection and quarantine of seedlings is the key to preventing the occurrence and spread of the disease.
PubMed: 38907519
DOI: 10.1094/PDIS-03-24-0677-PDN -
Plant Disease Jun 2024Cathaya argyrophylla [Chun & Kuang.] is an ancient relict plant and its embryonic development is similar to that of Pinus species. This has important scientific value...
Cathaya argyrophylla [Chun & Kuang.] is an ancient relict plant and its embryonic development is similar to that of Pinus species. This has important scientific value for studying the phylogeny of Pinaceae (Wu et al. 2023). In July 2022, root rot was detected in the seedling cultivation base of C. argyrophylla in Daozhen County, Guizhou Province, China (28.89 °N, 107.6 °E). The incidence of the disease was 30% (n = 100); the susceptible plants wilted, leaves withered, and roots showed brown-to-black lesions and rot. Ten root tissues were randomly collected from the edges of the lesions of six symptomatic susceptible plants. The tissues were sterilized with 75% alcohol for 30 seconds, followed by 2-minute immersion in 3% sodium hypochlorite. After washing with sterile water, the tissues were incubated on potato dextrose agar (PDA; BoWei, Shanghai) at 28 ℃ for five days. Four single-spore cultures were obtained using a single-spore isolation method (Gong et al., 2010). Single-spore cultures grew rapidly on PDA. After five days of incubation, the colonies were white and pink, indicating a large amount of aerial mycelia. Microconidia were ovate or ellipsoid, measuring 5.0-10.0 × 1.5-3.0 μm (n = 50); Macroconidia were falcate, slightly curved or straight, measuring 19.5-28.5 × 2.0-6.0 μm (n = 50). Based on morphological features, the pathogen was considered to be Fusarium spp. (Leslie and Summerell 2006). Three representative strains, GF5, GF6, and GF7, were selected for molecular identification, and genomic DNA was extracted to confirm morphological diagnosis. The internal transcribed spacer (ITS) (White et al. 1990) was amplified using primers ITS1/ITS4, and the β-tubulin gene (Varga et al. 2011) was amplified using primers Bt2a/Bt2b. The ITS and β-tubulin sequences were aligned with GenBank, and amplification of the genes from the three isolates was consistent. The ITS (OP482273) and β-tubulin (OR825353) sequences of GF5 were stored in GenBank, and their homology with Fusarium oxysporum HC131(accession numbers MW600442 and MW670451) was 99 to 100%. Maximum likelihood analysis using MEGA 11.0 showed that isolate GF5 belongs to F. oxysporum. The reconstructed phylogenetic tree confirmed the phylogenetic position of the isolate GF5. The pathogenicity test was carried out using GF5 and GF6 isolates. The taproots of ten 3-year-old C. argyrophylla plants were washed, and then the roots were immersed in a 2 × 106/mL conidial suspension for one hour. Ten plants with sterile water were used as controls. After planting in pots (30 × 25 cm) with sterilized forest soil, the plants were cultured in a greenhouse (25 ℃ and 12-hour photoperiod). Thirty days after inoculation, all plants inoculated with the isolated pathogen showed wilting symptoms, and the roots showed typical root rot symptoms, whereas the control group showed no symptoms. The pathogens re-isolated from all inoculated plants were morphologically identical and had ITS sequences identical to F. oxysporum, validating Koch's hypothesis. The pathogenicity test was repeated twice and similar results were obtained. Although this fungus has been previously reported to cause root diseases in hosts, such as Musa nana Lour. and Pinus massoniana Lamb. (He et al. 2010; Luo et al. 2020), to our knowledge, this is the first report of F. oxysporum causing root rot in C. argyrophylla. These findings provide a basis for the development of management strategies for C. argyrophylla infection.
PubMed: 38902878
DOI: 10.1094/PDIS-04-24-0723-PDN