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Fusarium spp. Associated with Dendrobium officinale Dieback Disease in China

Institute of Biotechnology, Zhejiang University, Hangzhou 310058, China
Kearney Agricultural Research and Extension Center, University of California Davis, 9240 South Riverbend Ave, Parlier, CA 93648, USA
Author to whom correspondence should be addressed.
J. Fungi 2022, 8(9), 919;
Submission received: 21 July 2022 / Revised: 26 August 2022 / Accepted: 27 August 2022 / Published: 29 August 2022
(This article belongs to the Special Issue Polyphasic Identification of Fungi 2.0)


A rare plant species of the Orchidaceae family, Dendrobium officinale is considered among the top ten Chinese medicinal herbs for its polysaccharide. Since 2021, when the dieback disease of D. officinale was first reported in Yueqing City, Zhejiang Province, China, Fusarium isolates (number = 152) were obtained from 70 plants in commercial greenhouses. The disease incidence ranged from 40% to 60% in the surveyed areas. Multilocus sequence analysis (MLSA) coupled with morphological characterization revealed that the collected isolates belonged to five species (sp.), viz., Fusarium concentricum, F. fujikuroi, F. nirenbergiae, F. curvatum, and F. stilboides, with isolation frequencies of 34.6%, 22.3%, 18.4%, 13.8%, and 10.5%, respectively. Notably, at least two Fusarium species were simultaneously isolated and identified from the infected plants. Finally, the pathogenicity test results demonstrated that such species were responsible for the dieback disease of D. officinale. However, F. concentricum and F. fujikuroi were more invasive compared to the other species in this study. To the best of the authors’ knowledge, this study was the first report of F. concentricum, F. curvatum, F. fujikuroi, F. nirenbergiae, and F. stilboides causing the dieback disease of D. officinale in China and worldwide. This work provides valuable data about the diversity and pathogenicity of Fusarium populations, which will help in formulating effective strategies and policies for better control of the dieback disease.

1. Introduction

Commonly known as Tiepishihu, Dendrobium officinale (Kimura and Migo) is an epiphytic, herbaceous, flowering, insect-pollinated, and perennial plant with a cylindrical-fibrous stem that is mostly utilized for pharmaceutical purposes in traditional Chinese medicine (TCM) [1,2,3]. Thus far, it has been demonstrated that several bioactive constituents, comprising polysaccharides, alkaloids, phenanthrenes, bibenzyls, saccharides, glycosides, lignans, phenolic acids, and phenylpropanoids, possess a wide variety of pharmacological properties, including antioxidant, antitumor, and hypolipidemic activities, as well as anti-fatigue, hypoglycemic, anti-fibrotic, hepatoprotective effect, and immuno-enhancement enhancement effects, along with outcomes for rheumatoid arthritis and diabetes [1,3,4].
Tiepishihu is extensively cropped in several provinces of China including Zhejiang, Anhui, Fujian, Guizhou, Guangxi, Sichuan, and Yunnan, with a total cultivation area of nearly 4000 hectares [3,4,5], and it is valued between $450 and $3100 per kg. Recently, micropropagation and greenhouse farming technologies have been utilized to enhance the rate of low natural regeneration of this plant species [2,3,5]. The seedlings derived from tissue cultures are thus transplanted from March to May in greenhouses to produce tillers, and the flowers emerge about 15 months later, between May and July. The stems are further harvested from the fields from the end of October to the beginning of March, approximately 31 months after planting. For three years after the first harvest, the plant can also produce commercial yields (i.e., stems) annually.
Currently, D. officinale production is seriously threatened by a number of fungal genera such as Alternaria alternata, Ceratobasidium sp. (species), Cladosporium cladosporioides, Colletotorichum gloeosporioides, C. fructicola, Epicoccum sorghinum, Fusarium equiseti, F. kyushuense, F. oxysporum, Neopestalotiopsis clavispora, Phoma multirostrata, and Sclerotium delphinii [6,7,8,9,10,11,12]. Among them, F. equiseti causes the dieback disease, which was initially identified in Fujian Province, China [8]. The pathogen results in considerable losses of approximately 50%. The infected plants exhibit wilting and dieback on apical meristem leaves, followed by drying and death of the tips [8].
Phytopathologists and clinical microbiologists have now devoted much attention to Fusarium (Wollenweber and Reinkin; Gibberella as sexual morphs) as a species-rich, heterogeneous, and ubiquitous genus of filamentous fungi [13,14,15]. In addition, the fusarioid taxa are able to adapt to a variety of climatic zones and colonize a wide range of ecosystems and hosts [13,16]. To date, this agriculturally and clinically important genus is estimated to be composed of over 400 phylogenetically distinct species, 23 monophyletic species complexes, and quite a few monotypic lineages [13,15,17]. The F. buharicum species complex (FBSC), F. fujikuroi species complex (FFSC), F. incarnatum-equiseti species complex (FIESC), F. lateritium species complex (FLSC), F. oxysporum species complex (FOSC), F. redolens species complex (FRSC), F. sambucinum species complex (FSaSC), and F. solani species complex (FSSC) have been accordingly reported to cause devastating plant diseases over the years [13,17,18,19]. Moreover, it has been difficult to discriminate closely related Fusarium species through macro-/microscopic characteristics due to the high morphological variability inter-/intra-species. Nowadays, several new species have been further delineated within the Fusarium spp. complexes by applying a polyphasic approach to taxonomy that combines morphology-based identification and genealogical concordance among portions of multiple phylogenetically informative genes (i.e., genealogical concordance phylogenetic species recognition: GCPSR sensu). This technique has thus led to a major improvement in the Fusarioid fungi taxonomy and nomenclature [13,16,17,18,19,20].
The dieback disease is spreading in different Tiepishihu plantation areas, but there are no effective and eco-friendly control measures available. In this context, integrated disease management strategies, including biological control agents, biofertilizers, chemical fungicides, cultural practices, resistant varieties, forecasting models, and sanitation methods are required to minimize the incidence rate of plant pathogens and maintain profitable, sustainable Tiepishihu production [21,22].
Hitherto, little has been known about the species, or about the population structure and phenotypic characters of Fusarium species causing the dieback disease of D. officinale, neither in China nor elsewhere in the world. Against this background, this study aimed to identify and characterize the Fusarium spp. diversity, and then to assess the virulence of the disease for Tiepishihu.

2. Materials and Methods

2.1. Sample Collection, Fungal Isolation, and Morphological Characterization

The D. officinale plants (70) with dieback symptoms were initially sampled from commercial greenhouses in Yueqing (28.07° N, 120.57° E), Zhejiang Province, China. The incidence rate of the disease was assessed by visual observations, and then calculated for the presence or absence of symptomatic plants in the surveyed greenhouses. Afterward, the symptomatic stem tips were cut with a sterilized scalpel, superficially disinfected with a 2% solution of sodium hypochlorite (0.1% active ingredient of chlorine; [23]) for 1 min and 75% ethanol for 30 s, rinsed thrice with sterile distilled water, air dried on sterile filter papers under aseptic conditions, and finally placed onto potato dextrose agar (PDA) medium. The plates were subsequently incubated at 25 °C in the dark, and the colonies were purified by the hyphal tip method and then sub-cultured on the PDA and carnation leaf agar (CLA) media for morphological observation [13,24]. The conidial morphology and sporulation of the pure fungal colonies were finally examined under a Nikon Eclipse microscope (Japan).

2.2. DNA Sequencing and Molecular Phylogeny

DNA was extracted from the mycelia of 7-day-old cultures of the representative isolates using the Plant Genomic DNA kit (Tiangen, China) according to the manufacturer’s instructions. The fragments of the translation elongation factor 1-alpha (tef1), second largest subunit of RNA polymerase II gene (rpb2), and β-tubulin (tub2) genes were then amplified by the primers EF-1/EF-2, RPB2-5f2/RPB2-7cr, and Tub2F/Tub2R, respectively [13,23]. The polymerase chain reaction (PCR) was also performed in 25 μL volumes, containing 1 µL of genomic DNA, 12.5 μL 2 × Phanta® Flash Master Mix Dye Plus (Vazyme, Nanjing, China), 9.5 μL of DNase-free water, and 1 μL of each forward and reverse primer (10 μM). Notably, the cycling conditions included the initial denaturation of 30 s at 98 °C, followed by 30 cycles of denaturation at 98 °C for 10 s, the annealing at 52 (tef1), 59 (rpb2), and 55 (tub2) for 10 s, the extension of 10 s at 72 °C, as well as the final extension at 72 °C for 1 min. The PCR products were first visualized on a 1% (w/v) agarose gel, and then Sanger sequencing was conducted by Sangon Biotech Co., Ltd. (Shanghai, China) for both directions to ensure high accuracy. The accession number of all generated sequences in this study was further obtained from the GenBank, as listed in Table 1. The aligned sequences of the novel isolates were also subjected to the Basic Local Alignment Search Tool (BLAST) to collect related sequences for inclusion in phylogenetic analysis. The BLASTN searches were fulfilled using the rpb2, tef1, and tub2 sequences against the Nucleotide collection (nr/nt) database by restricting the material type. Multiple sequence alignments were correspondingly inferred in Molecular Evolutionary Genetics Analysis (MEGA) X software version 10.2.4 [25] using the MUSCLE (multiple sequence comparison by log-expectation) program [26] and refined manually if necessary. To generate concatenated datasets, single-gene sequences (tef1, rpb2, and tub2) were manually combined utilizing the BioEdit version 7.1 [27]. The phylogenetic trees were further constructed based on the individual and concatenated sequences (rpb2, tef1, and tub2) using the MEGA X software. The maximum likelihood (ML) and neighbor-joining (NJ) methods were also employed to approximate the distances and complete bootstrapping. As well as the general time reversible model assuming a discrete gamma distribution and invariant sites (GTR+I+G) for the combined aligned dataset, the Tamura-Nei model with gamma-distributed (TN93+G) for rpb2 and the Kimura two parameter model (K2+G) for tef1 were applied as the best evolutionary models for the phylogenetic analyses [25]. The topological support was then determined by 1000 bootstrap replicates. The sequences from the Fusarium spp. type strains, initially identified as closely related to the sequences here, were finally included by the preliminary BLAST searches (Table 1).

2.3. Pathogenicity Studies

To reproduce the dieback disease symptoms, the fungal isolates were tested for pathogenicity on the original host. A small, excised wound was accordingly made on the tip of each intact stem after being swabbed with ethanol 75% and washed with sterile water, then a mycelial agar disc (5 mm diameter) from each of the 7-day-old cultures of the fungal isolates was placed onto the surfaces of each stem tip and wrapped with Parafilm [8]. Afterward, the incubated plants were placed in a growth chamber at 25 °C and 75% relative humidity (RH) and maintained for 14 days. In contrast, the control plants received non-colonized agar plugs. Of note, the test was independently replicated thrice. All inoculated plants were visually assessed on a daily basis for up to two weeks. To fulfill Koch’s postulates, the same fungal isolates were re-isolated and their identity was confirmed by the tef1 sequence data. To evaluate the disease severity, pear fruits (Pyrus pyrifolia) were also sterilized with 75% ethanol (3 min) and washed with sterile distilled water. Next, a mycelial agar disc (9 mm diameter) was placed on the fruit surface and covered with Parafilm to maintain high humidity [28]. All inoculated fruits were incubated under the same condition as mentioned above for one week. The fresh PDA agar plugs were further used as a negative control. The fruit rot diameter was finally measured by an electronic caliper seven days post inoculation (DPI). Each treatment included three replicates, and the experiment was independently repeated at least twice for both tests.

3. Results

3.1. Field Survey, Disease Symptoms, and Pathogen Isolations

In September 2021, symptoms of the dieback disease on D. officinale emerged in Yueqing, Zhejiang Province, China. According to the field observations, high temperature, high humidity, and poor ventilation would accelerate the incidence rate of this condition, which was at about 40–60% based on the number of plants with dieback disease symptoms recorded in 30 rows randomly picked. The symptoms appeared as chlorotic, blighted, and wilted leaves of the apical meristem with the shoot tip showing dark brown necrosis, dieback, and eventually shoot death (Figure 1). A total of 152 Fusarium-like isolates were also recovered from 70 infected plants, and 20 representative isolates were selected for further analysis (Table 2). Each isolate was recovered from different infected stems. Consistent with their morphological traits as well as molecular methods, the isolated fungi belonged to five genera, encompassing F. concentricum, F. curvatum, F. fujikuroi, F. nirenbergiae, and F. stilboides. Comparing the isolation frequency accordingly revealed that F. concentricum was the most abundant species, followed by F. curvatum, F. fujikuroi, and F. nirenbergiae, while F. stilboides was found the least (Table 2). Interestingly, two, and occasionally more than two, different Fusarium spp. were simultaneously isolated from some samples, and finally confirmed by the tef1 and rpb2 sequence analyses.

3.2. Morphological Identification

The phenotypic criteria of the representative isolates obtained from the symptomatic stem tips matched with the descriptions of F. concentricum, F. fujikuroi, F. nirenbergiae, F. curvatum, and F. stilboides morphology.
In this regard, F. concentricum showed yellow-white, abundant, densely lanose to velutinous aerial hyphae with concentric rings on the PDA. Also, the colonies produced mainly 3-5-septate, naviculate to fusiform, slender macroconidia (Sporodochial conidia) with beaked apical and foot-shaped basal cells. Microconidia (aerial conidia) were also obovoid to fusoid, predominantly with no septa, but occasionally with 1 septum, and borne on mono or poly-phialides found in the aerial mycelia. However, chlamydospores were not observed. On the CLA, orange sporodochia were found (Figure 2).
On the PDA, F. curvatum formed abundant floccose aerial mycelium with pale rosy white hue. Microconidia were also hyaline, ellipsoidal to falcate, 0-1-septate, and bore forming small false heads (i.e., short unbranded conidiophores) on the tips of the phialides. Besides, macroconidia were hyaline, 2-4-septate, banana-shaped, with blunt to papillate apical and blunt basal cells. Also, chlamydospores were not observed, and orange sporodochia formed on the carnation leave (Figure 2).
The F. fujikuroi colonies on the PDA consisted of floccose white aerial mycelia that became gray-violet or magenta with age, lacking chlamydospores. Notably, some swollen cells could develop in the hyphae and superficially appear chlamydospores or pseudochlamydospores. Aerial conidia were also oval-shaped with a flattened base and 0-1-septate on the CLA. The long, slender, usually 3–6-septate macroconidia further proliferated on the monophialides of the branched conidiophores in the sporodochia. Moreover, the pale orange sporodochia was sparsely produced on the CLA (Figure 2).
The F. nirenbergiae colonies were pale vinaceous to burly-wood color, with abundant flocculent aerial hyphae on the PDA. Sporodochial conidia also formed small false heads on the tips of the phialides, lucid, oval to falcate with 0-1-septa. As well, macroconidia were hyaline, generally 3-septate, and in the shape of crescents or sickles with an attenuated to semi-papillate, curved apical and foot-shaped basal cells. The globose to spherical, aseptate chlamydospores were further produced terminally or intercalary. The aerial mycelium also formed abundantly bright orange sporodochia on the CLA (Figure 2).
The aerial mycelia of F. stilboides strains were cottony, velvety, reddish orange to maroon on the PDA. The aerial conidia were also long, cylindrical, smooth-walled, 3-5-septate, straight to almost slightly flexuous in the center and sharpened at the apices with marked foot-shaped cells. Moreover, formation of orange sporodochia was observed on CLA. The microconidia were typically obovoid to elliptical and 0-1-septate, and chlamydospores were present (Figure 2).

3.3. Molecular Identification and Phylogenetic Analyses

The PCR amplified partial sequences of the genes tef1, rpb2, and tub2, yielded 651, 718, and 481 bp fragments, respectively. The BLASTN searches against all Fusarium sequences in the GenBank additionally showed that the 20 representative isolates included in this study shared 99–100% similarity with type-strains of five Fusarium spp., namely, F. concentricum, F. fujikuroi, F. nirenbergiae, F. curvatum, and F. stilboides, which supported previous efforts for the identification of these pathogens based on the macro and micro-morphological characteristics. To clarify the phylogenetic relations, the phylogenetic trees were built here from the single genes tef1 and rpb2. These trees included several sequences from the new isolates, Fusarium type strains, plus a few non-type strains. The given trees further supported the identification of the D. officinale isolates (Supplementary Figure S1). The partial tub2 sequences also displayed close similarity with the Fusarium species but provided an insufficient resolution to identify them. For further molecular verification, multilocus phylogenetic analysis (MLSA) was further performed based on 1850 nucleotide positions among 91 in-group taxa, including clades corresponding to FOSC, FFSC, FLSC, and FIESC. The MLSA tree accordingly indicated that the D. officinale isolates in the present study clustered unambiguously with F. concentricum, F. fujikuroi, F. nirenbergiae, F. curvatum, and F. stilboides type strains with the bootstrap values of 99%, 99%, 96%, 95%, and 99%, respectively (Figure 3). The topologies of the trees obtained from each individual gene also resembled each other and were, above all, similar to the MLSA tree (Supplementary Figure S1). Nonetheless, the concatenated dataset, in addition to all the individual phylogenies, clearly determined the phylogenetic relationship and taxonomy of Tiepishihu isolates in the Fusariod taxa. Moreover, the F. equiseti strain DFS, as a pathogen of the dieback disease of D. officinale in China, fell strongly with the F. equiseti clade, which belonged to the FIESC (Supplementary Figure S1).

3.4. Pathogenicity Assays

Two weeks after inoculation, the pathogenicity test results revealed that the isolates from five Fusarium spp. had the typical black brown necrosis and the dieback symptoms on the tip of D. officinale (tie-pie variety) stems, which were congruent with the field observations, while no symptoms developed on the control plants inoculated with the agar media. All these fungal species were also re-isolated from the inoculated plants, and identified using the tef1 locus, thereby fulfilling Koch’s postulates (Figure 4A). Notably, the dieback disease symptoms incited by each pathogen were indistinguishable in the field. As such, all Fusarium spp. isolates were pathogenic on Tiepishihu and caused the dieback disease in these inoculation studies. Furthermore, F. concentricum and F. fujikuroi, among the assayed isolates, indicated higher virulence on pears than the others, followed by F. nirenbergiae and F. curvatum, which had relatively similar disease severity, whereas F. stilboides showed the lowest virulence in this respect (Figure 4B; Table 3).

4. Discussion

The dieback disease has already plagued the D. officinale industry with a high incidence rate in Zhejiang Province, China. On the basis of the MLSA supported by morphological observations in this study, five distinct taxa, viz., F. concentricum, F. fujikuroi, F. nirenbergiae, F. curvatum, and F. stilboides, causing the dieback disease on Tiepishihu, were diagnosed. The study findings also suggested that the Fusarium species associated with this condition on Tiepishihu were more diverse than the ones previously recorded [8]. The Koch’s postulates correspondingly showed that the Fusarium spp. Isolates were infective in nature, with slight variations in virulence.
The newly inflicted Fusarium spp. On D. officinale have been also found as plant pathogens and innocuous saprophytes, e.g., F. concentricum causing fruit blotch on Hibiscus sabdariffa, stem rot on Paris polyphylla, fruit rot on pepper and banana, leaf spot on mango, wilt on Podocarpus macrophyllus, and ear rot on maize, originally named by Nirenberg and O’Donnell [24,29,30,31,32]. F. curvatum has been also described as a new taxon by Lombard et al. [16], originally named F. oxysporum (matthiolae and meniscoideum formae speciales), which was regarded as a FOSC member. However, little is known about this species, and it has been reported as a pathogen on yam [13,16,24,33]. In addition, F. fujikuroi is a well-studied taxon with sexual stage, Gibberella fujikuroi (Sawada), which is known as a pathogen on various host plants including cotton, Echinochloa sp., grapes, maize, Macleaya cordata, Reineckia carnea, rice, soybean, strawberries, sugarcane, wheat, and Zanthoxylum armatum [24,32,34]. Moreover, F. nirenbergiae was recently resolved from the FOSC and included several formae speciales of F. oxysporum (viz., dianthi, chrysanthemi, bouvardiae, adices-lycopersici, cubense, lycopersici, and passiflorae) and clinically relevant strains [13,16,24]. This pathogen has been further associated with multiple diseases such as saffron corm rot, wilt on Acer negundo, Dipladenia sp., and passion fruit [16,35,36,37]. Fusarium stilboides is an FLSC member that has been recorded as a pathogen on bamboo, Capsicum annuum, carnation, coffee, and passion fruit [13,38,39,40,41].
Although macro- and micro-morphological observations alone may be insufficient, several critical characteristics can provide useful information for discriminating the Fusarium species [13,14,15,16]. Hence, the detailed and close morphological examinations form an important part in the classification of this genus. In this line, F. curvatum produces high curvature macroconidia and aerial polyphialidic conidiogenous cells, differentiating it from F. nirenbergiae and other species [13,14,16]. Moreover, chlamydospores are readily present in F. nirenbergiae, while this feature is not known for F. concentricum, F. fujikuroi, and F. curvatum [16,17,18,19,20,21,22,23,24]. However, F. stilboides can produce chlamydospores even though this trait is not taxonomically useful [24]. Additionally, F. nirenbergiae cannot form polyphialides, and resembles F. oxysporum in this respect [16,17,18,19,20,21,22,23,24]. Morphologically, both F. fujikuroi and F. concentricum proliferate microconidia in false heads or chains, whereas the conidiophores of the aerial mycelium are only sparsely branched in F. concentricum with only a few polyphialides, and conidia in F. fujikuroi conidia are from polyphialides, and less often from monophialides [24,30,32].
The validity of morphological identification in this study was thus confirmed by the phylogenetic analyses derived from the molecular results. The tef1, rpb2, and tub2 genetic barcodes were thus selected for this purpose because they consisted of phylogenetically informative sequences for the differentiation and classification of Fusarium species [13,16,19,20].
The tef1 phylogeny accordingly demonstrated better resolution at the species level in comparison with rpb2 and tub2. For the concatenated gene analyses, the topologies of the trees inferred for individual genes were also evaluated visually to establish that the overall tree topology of the single locus datasets were similar to each other and to that of the tree acquired from the combined dataset alignment. In the MLSA tree, the Fusarium isolates from D. officinale in the present study were phylogenetically different from each other and were situated within the FOSC, FFSC, and FLSC clades with F. concentricum CBS 450.97, F. curvatum CBS 238.94, F. fujikuroi CBS 221.76, F. nirenbergiae CBS 840.88, and F. stilboides CBS 746.79 type strains, while none of them fell in the FBSC, FRSC, and FsaSC clades. Even if F. nirenbergiae and F. curvatum were placed in the same clade, they formed two distinct well-supported subclades, which correlated with clade VIII resolved by Lombard et al. [16]. Furthermore, the tree topology of the concatenated dataset in this study was closely similar to the trees developed by Lombard et al. [16], Crous et al. [13], and Yilmaz et al. [19].
Interestingly, it has been concluded that the dieback is a disease complex, induced by one or more Fusarium spp. (viz., F. concentricum, F. curvatum, F. fujikuroi, F. nirenbergiae, and F. stilboides), as observed in manifold crops [33,42,43,44]. For instance, eight species including F. asiaticum, F. equiseti, F. fujikuroi, F. graminearum, F. meridionale, F. oxysporum, F. proliferatum, and F. verticillioides, have been evidenced to incite corn sheath rot in Sichuan Province, China [44]. Similarly, ten Fusarium species, viz., F. asiaticum, F. commune, F. cugenangense, F. curvatum, F. fujikuroi, F. gossypinum, F. nirenbergiae, F. odoratissimum, F. solani and F. verticillioides, have been detected to cause wilt on yam [33].
Despite much effort, there was no success in defining the pathogen-specific diagnostic criteria for these five taxa, which induced the dieback disease on D. officinale. Further surveys are thus required to establish the species-specific symptoms of this condition. Additionally, the symptoms on some stem tips may slightly differ in respect of intensity or color, suggesting that such symptoms may have been due to secondary infections by saprophytic microbes or affected by environmental conditions, such as high humidity or unfavorable ventilation, as documented in previous research [21,22,35,45,46,47,48,49,50].

5. Conclusions

In sum, the study data here confirmed that the losses in D. officinale yields were caused by F. concentricum, F. curvatum, F. fujikuroi, F. nirenbergiae, and F. stilboides. Notably, the incidence rate of these local outbreaks could be triggered by environmental factors, and it is expected to increase in the future because of both climate change and susceptible cultivars. Regarding the significance of this study, it provided information on the biodiversity and epidemiology of Fusarium spp. associated with the dieback disease, which can contribute to the development of breeding programs and disease management strategies.

Supplementary Materials

The following supporting information can be downloaded at:, Figure S1: Phylogenetic tree of the Fusarium species resulting from maximum likelihood based on the sequence of tef1 gene. Bootstrap support values were given at the nodes. Isolates isolated in this study are shown by a black circle (●), while F. equiseti strain DFS is indicated by a black square (■).

Author Contributions

Conceptualization, design of the experiments, methodology, bioinformatic analysis, interpretation of the data, and writing the original manuscript, S.A.M.; editing the manuscript, T.M.; advising on the experiments and providing resources, W.C.; validation, funding acquisition, supervision, B.M. All authors have read and agreed to the published version of the manuscript.


This work was funded by Key Research and Development Projects in Zhejiang Province (No. 2018C02034).

Institutional Review Board Statement

Not applicable.

Informed Consent Statement

Not applicable.

Data Availability Statement

Sequences have been deposited in GenBank (Table 1). The data presented in this study are openly available in NCBI. Publicly available datasets were analyzed in this study. These data can be found here: (accessed on 2 April 2022).

Conflicts of Interest

The authors declare no conflict of interest.


  1. Nie, S.; Cui, S.W.; Xie, M. Glucomannans from Dendrobium officinale and aloe. Bio. Poly. 2018, 6, 295–347. [Google Scholar] [CrossRef]
  2. Cheng, J.; Dang, P.P.; Zhao, Z.; Yuan, L.C.; Zhou, Z.H.; Wolf, D. An assessment of the Chinese medicinal Dendrobium industry: Supply, demand and sustainability. J. Ethnopharma. 2019, 229, 81–88. [Google Scholar] [CrossRef] [PubMed]
  3. Sarsaiya, S.; Jain, A.; Jia, Q.; Fan, X.; Shu, F.; Chen, Z. Molecular identification of endophytic fungi and their pathogenicity evaluation against Dendrobium nobile and Dendrobium officinale. Inter. J. Mole. Sci. 2020, 21, 316. [Google Scholar] [CrossRef]
  4. Shan, T.; Zhou, L.; Li, B.; Chen, X.; Guo, S.; Wang, A. The plant growth-promoting fungus MF23 (Mycena sp.) increases production of Dendrobium officinale (Orchidaceae) by affecting nitrogen uptake and NH4+ assimilation. Front. Plant Sci. 2021, 12, 693561. [Google Scholar] [CrossRef] [PubMed]
  5. Teoh, E.S. Dwelling on rocks (Shihu). In Orchids as Aphrodisiac, Medicine or Food; Springer: Berlin/Heidelberg, Germany, 2019; Volume 4, pp. 69–86. [Google Scholar] [CrossRef]
  6. Zhang, Y.Q.; Lin, B.Y.; Zou, M.Y.; Liang, J.X.; Hu, H.Q. First report of Fusarium wilt of Dendrobium officinale caused by Fusarium oxysporum in China. Plant Dis. 2017, 101, 1039. [Google Scholar] [CrossRef]
  7. Xie, Y.Y.; Wang, L.P.; Fang, L.; Wang, H.R. First report of leaf spot caused by Phoma multirostrata var. microspora on Dendrobium officinale in Zhejiang Province of China. Plant Dis. 2018, 102, 1655. [Google Scholar] [CrossRef]
  8. Guo, M.; Li, B.; Wang, R.; Liu, P.; Chen, Q. Occurrence of dieback disease caused by Fusarium equiseti on Dendrobium officinale in China. Crop Prot. 2020, 137, 105209. [Google Scholar] [CrossRef]
  9. Xiao, C.; Li, R.; Song, X.; Tian, X.; Zhao, Q. First report of soft rot on Dendrobium officinale caused by Epicoccum sorghinum in China. Plant Dis. 2021, 1063. [Google Scholar] [CrossRef]
  10. Xiao, C.; Li, R. Detection and control of Fusarium oxysporum from soft rot in Dendrobium officinale by Loop-Mediated isothermal amplification assays. Biology 2021, 10, 1136. [Google Scholar] [CrossRef]
  11. Cao, P.; Zheng, Z.; Fang, Y.; Han, X.; Zou, H.; Yan, X. First report of stem rot caused by Fusarium kyushuense on Dendrobium officinale in China. Plant Dis. 2022, 31, 2257. [Google Scholar] [CrossRef]
  12. Cao, P.; Zheng, Z.; Han, X.; Zou, H.; Yan, X. Occurrence of Neopestalotiopsis clavispora causing leaf spot on Dendrobium officinale in China. Plant Dis. 2022, 12, 1761. [Google Scholar] [CrossRef] [PubMed]
  13. Crous, P.W.; Lombard, L.; Sandoval-Denis, M.; Seifert, K.A.; Schroers, H.J.; Chaverri, P.; Gené, J.; Guarro, J.; Hirooka, Y.; Bensch, K.; et al. Fusarium: More than a node or a foot-shaped basal cell. Stud. Mycol. 2021, 98, 100116. [Google Scholar] [CrossRef] [PubMed]
  14. Kumar, S. Molecular taxonomy, diversity, and potential applications of genus Fusarium. In Industrially Important Fungi for Sustainable Development; Springer: Berlin/Heidelberg, Germany, 2021; pp. 277–293. [Google Scholar] [CrossRef]
  15. O’Donnell, K.; Whitaker, B.; Laraba, I.; Proctor, R.; Brown, D.; Broders, K.; Kim, H.S.; McCormick, S.P.; Busman, M.; Aoki, T.; et al. DNA sequence-based identification of Fusarium: A work in progress. Plant Dis. 2021, 106, 1597–1609. [Google Scholar] [CrossRef] [PubMed]
  16. Lombard, L.; Sandoval-Denis, M.; Lamprecht, S.C.; Crous, P.W. Epitypification of Fusarium oxysporum: Clearing the taxonomic chaos. Persoonia 2019, 43, 1–47. [Google Scholar] [CrossRef] [PubMed]
  17. Crous, P.W.; Hernández-Restrepo, M.; van Iperen, A.L.; Starink-Willemse, M.; Sandoval-Denis, M.; Groenewald, J.Z. Citizen science project reveals novel Fusarioid fungi (Nectriaceae, Sordariomycetes) from urban soils. Fungal Sys. Evol. 2021, 8, 101–127. [Google Scholar] [CrossRef] [PubMed]
  18. Nucci, M.; Ramos, J.F. Fusarium and Fusariosis, reference module in biomedical sciences. In Reference Module in Biomedical Sciences; Elsevier: Amsterdam, The Netherlands, 2021. [Google Scholar] [CrossRef]
  19. Yilmaz, N.; Sandoval-Denis, M.; Lombard, L.; Visagie1, C.M.; Wingfield1, B.D.; Crous, P.W. Redefining species limits in the Fusarium fujikuroi species complex. Persoonia 2021, 46, 129–162. [Google Scholar] [CrossRef] [PubMed]
  20. McTaggart, A.R.; James, T.Y.; Shivas, R.G.; Drenth, A.; Wingfield, B.D.; Summerell, B.A. Population genomics reveals historical and ongoing recombination in the Fusarium oxysporum species complex. Stud. Mycol. 2021, 99, 100132. [Google Scholar] [CrossRef]
  21. Hay, F.; Stricker, S.; Gossen, B.D.; McDonald, M.R.; Heck, D.; Hoepting, C.; Sharma, S.; Pethybridge, S. Stemphylium Leaf blight: A re-emerging threat to onion production in eastern north America. Plant Dis. 2021, 12, 3780–3794. [Google Scholar] [CrossRef]
  22. Riseh, R.S.; Skorik, Y.A.; Thakur, V.K.; Pour, M.M.; Tamanadar, E.; Noghabi, S.S. Encapsulation of plant biocontrol bacteria with alginate as a main polymer material. Int. J. Mol. Sci. 2021, 22, 11165. [Google Scholar] [CrossRef]
  23. Copes, W.E.; Ojiambo, P.S. Efficacy of hypochlorite in disinfesting nonfungal plant pathogens in agricultural and horticultural plant production: A Meta-Analysis. Plant Dis. 2021, 105, 4084–4094. [Google Scholar] [CrossRef]
  24. Leslie, J.F.; Summerell, B.A. The Fusarium Laboratory Manual; John Wiley & Sons: Hoboken, NJ, USA, 2006. [Google Scholar] [CrossRef]
  25. Kumar, S.; Stecher, G.; Knyaz, M.; Li, C.; Tamura, K. MEGA X: Molecular evolutionary genetics analysis across computing platforms. Mol. Biol. Evol. 2018, 35, 1547–1549. [Google Scholar] [CrossRef] [PubMed]
  26. Edgar, R.C. MUSCLE: Multiple sequence alignment with high accuracy and high throughput. Nucleic Acids Res. 2004, 32, 1792–1797. [Google Scholar] [CrossRef] [PubMed]
  27. Raza, M.; Zhang, Z.F.; Hyde, K.D.; Diao, Y.Z.; Cai, L. Culturable plant pathogenic fungi associated with sugarcane in southern China. Fungal Divers. 2019, 99, 1–104. [Google Scholar] [CrossRef]
  28. Liu, F.; Tang, G.; Zheng, X.; Li, Y.; Sun, X.; Qi, X. Molecular and phenotypic characterization of Colletotrichum species associated with anthracnose disease in peppers from Sichuan Province, China. Sci. Rep. 2016, 6, 32761. [Google Scholar] [CrossRef] [PubMed]
  29. Nirenberg, H.I.; O’Donnell, K. New Fusarium species and combinations within the Gibberella fujikuroi species complex. Mycologia 1998, 90, 434–458. [Google Scholar] [CrossRef]
  30. Du, Q.; Duan, C.X.; Li, S.C.; Tang, Z.L.; Luo, J.Y. First report of maize ear rot caused by Fusarium concentricum in China. Plant Dis. 2020, 104, 1539. [Google Scholar] [CrossRef]
  31. Huda-Shakirah, A.R.; Nur-Salsabila, K.; Mohd, M.H. First report of Fusarium concentricum causing fruit blotch on roselle (Hibiscus sabdariffa). Aust. Plant Dis. 2020, 15, 15. [Google Scholar] [CrossRef]
  32. Qin, D.; Jiang, Y.; Zhang, R.; Ali, E.; Huo, J.; Li, Y. First report of Fusarium concentricum causing wilt on Podocarpus macrophyllus in China. Plant Dis. 2021, 18. [Google Scholar] [CrossRef]
  33. Dongzhen, F.; Xilin, L.; Xiaorong, C.; Wenwu, Y.; Yunlu, H.; Yi, C.; Jia, C.; Zhimin, L.; Litao, G.; Tuhong, W.; et al. Fusarium species and Fusarium oxysporum species complex genotypes associated with yam wilt in south-central China. Front. Microbiol. 2020, 11, 1964. [Google Scholar] [CrossRef]
  34. Zhu, Y.; Abdelraheem, A.; Wedegaertner, T.; Nichols, R.; Zhang, J.F. First report of Fusarium fujikuroi causing wilt on Pima cotton (Gossypium barbadense) seedlings in New Mexico, USA. Plant Dis. 2021, 105, 228. [Google Scholar] [CrossRef]
  35. Mirghasempour, S.A.; Studholme, D.J.; Chen, W.; Cui, D.; Mao, B. Identification and characterization of Fusarium nirenbergiae associated with saffron corm rot disease. Plant Dis. 2022, 106, 486–495. [Google Scholar] [CrossRef] [PubMed]
  36. Aiello, D.; Fiorenza, A.; Leonardi, G.R.; Vitale, A.; Polizzi, G. Fusarium nirenbergiae (Fusarium oxysporum species complex) causing the wilting of passion fruit in Italy. Plants 2021, 10, 2011. [Google Scholar] [CrossRef]
  37. Aiello, D.; Gusella, G.; Vitale, A.; Polizzi, G. Characterization of Fusarium nirenbergiae and F. elaeidis causing diseases on Dipladenia and Grevillea plants. Eur. J. Plant Pathol. 2022, 14, 885–896. [Google Scholar] [CrossRef]
  38. Mirkova, E.; Karadjova, Y. New species of Fusarium in glasshouse carnations in Bulgaria. Biotechnol. Biotechnol. Equip. 1994, 8, 8–12. [Google Scholar] [CrossRef]
  39. Hurley, B.P.; Govender, P.; Coutinho, T.A.; Wingfield, B.D.; Wingfield, M.J. Fungus gnats and other Diptera in South African forestry nurseries and their possible association with the pitch canker fungus. S. Afr. J. Sci. 2007, 103, 43–46. [Google Scholar]
  40. Sandoval-Chávez, R.A.; Martínez-Peniche, R.Á.; Hernández-Iturriaga, M.; Fernández-Escartín, E.; Arvizu-Medrano, S.; Soto-Muñoz, L. Postharvest biological and chemical control of Fusarium stilboides on bell pepper (Capsicum annuum L.) Revista Chapingo. Serie Horticul. 2011, 17, 161–172. [Google Scholar] [CrossRef]
  41. Tshilenge-Djim, P.; Muengula-Manyi, M.; Kingunza-Mawanga, K.; Ngombo-Nzokwani, A.; Tshilenge-Lukanda, L.; Kalonji-Mbuyi, A. Field assessment of th e potential role of Fusarium species in the pathogenesis of coffee wilt diseas e in democratic republic of congo. Asian Res. J. Agric. 2016, 2, 1–7. [Google Scholar] [CrossRef]
  42. López-Moral, A.; Lovera, M.; Raya, M.D.C.; Cortés-Cosano, N.; Arquero, O.; Trapero, A.; Agustí-Brisach, C. Etiology of branch bieback and shoot blight of english walnut caused by Botryosphaeriaceae and Diaporthe species in southern Spain. Plant Dis. 2020, 104, 533–550. [Google Scholar] [CrossRef]
  43. Guo, Z.; Yu, Z.; Li, Q.; Tang, L.; Guo, T.; Huang, S.; Mo, J.; Hsiang, T.; Luo, S. Fusarium species associated with leaf spots of mango in China. Microb. Pathog. 2021, 150, 104736. [Google Scholar] [CrossRef]
  44. Wang, W.; Wang, B.; Sun, X.; Qi, X.; Zhao, C.; Chang, X. Symptoms and pathogens diversity of corn Fusarium sheath rot in Sichuan Province, China. Sci. Rep. 2021, 11, 2835. [Google Scholar] [CrossRef]
  45. Yu, J.; Babadoost, M. Occurrence of Fusarium commune and F. oxysporum in horseradish roots. Plant Dis. 2013, 97, 453–460. [Google Scholar] [CrossRef] [PubMed]
  46. Asselin, J.; Bonasera, J.M.; Beer, S.V. PCR primers for detection of Pantoea ananatis, Burkholderia spp., and Enterobacter sp. from onion. Plant Dis. 2016, 100, 836–846. [Google Scholar] [CrossRef] [PubMed]
  47. Swett, C.L.; Science, P.; Architecture, L.; Park, C.; Sharon, C. Evidence for a hemibiotrophic association of the pitch canker pathogen Fusarium circinatum with Pinus radiata. Plant Dis. 2016, 100, 79–84. [Google Scholar] [CrossRef] [PubMed]
  48. Degani, O.; Movshowitz, D.; Dor, S.; Meerson, A.; Goldblat, Y.; Rabinovitz, O. Evaluating azoxystrobin seed coating against maize late wilt disease using a sensitive qPCR-based method. Plant Dis. 2019, 103, 238–248. [Google Scholar] [CrossRef]
  49. Mayorquin, J.S.; Nouri, M.T.; Peacock, B.B.; Trouillas, F.P.; Douhan, G.W.; Kallsen, C. Identification, pathogenicity, and spore trapping of Colletotrichum karstii associated with twig and shoot dieback in California. Plant Dis. 2019, 103, 1464–1473. [Google Scholar] [CrossRef] [PubMed]
  50. Bock, C.H.; Barbedo, J.G.A.; Del Ponte, E.M.; Bohnenkamp, D.; Mahlein, A.K. From visual estimates to fully automated sensor-based measurements of plant disease severity: Status and challenges for improving accuracy. Phytopathol. Res. 2020, 2, 9. [Google Scholar] [CrossRef] [Green Version]
Figure 1. Natural symptoms on Dendrobium officinale tissue associated with Fusarium spp. (A) Healthy plant; (B) typical dieback on the stem.
Figure 1. Natural symptoms on Dendrobium officinale tissue associated with Fusarium spp. (A) Healthy plant; (B) typical dieback on the stem.
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Figure 2. Morphological characteristics of Fusarium species isolated from infected Dendrobium officinale stems. (A) Front side on PDA; (B) Reverse side on PDA; (C) Sporodochia on Carnation Leaf Agar; (D) Macroconidia; (E) Microconidia. Scale bars: D–E = 10 µm.
Figure 2. Morphological characteristics of Fusarium species isolated from infected Dendrobium officinale stems. (A) Front side on PDA; (B) Reverse side on PDA; (C) Sporodochia on Carnation Leaf Agar; (D) Macroconidia; (E) Microconidia. Scale bars: D–E = 10 µm.
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Figure 3. Multilocus phylogenetic tree resulting from maximum likelihood analysis of concatenated rpb2, tef1, and tub2 sequences. The tree shows the phylogenetic relationships of Fusarium spp. causing dieback disease in Dendrobium officinale. Isolates recovered from Tiepishihu in this study are indicated by a black circle (●). Clades including isolates obtained from D. officinale are shaded in color. The tree is rooted to Macroconia leptosphaeriae CBS 100001. Bootstrap values are shown above the branches. Subdivision of the Fusarium clade represents the recognized species complexes.
Figure 3. Multilocus phylogenetic tree resulting from maximum likelihood analysis of concatenated rpb2, tef1, and tub2 sequences. The tree shows the phylogenetic relationships of Fusarium spp. causing dieback disease in Dendrobium officinale. Isolates recovered from Tiepishihu in this study are indicated by a black circle (●). Clades including isolates obtained from D. officinale are shaded in color. The tree is rooted to Macroconia leptosphaeriae CBS 100001. Bootstrap values are shown above the branches. Subdivision of the Fusarium clade represents the recognized species complexes.
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Figure 4. Artificial symptoms on tip of Dendrobium officinale stems (A), and Pyrus pyrifolia fruits (B) after inoculation with Fusarium species.
Figure 4. Artificial symptoms on tip of Dendrobium officinale stems (A), and Pyrus pyrifolia fruits (B) after inoculation with Fusarium species.
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Table 1. GenBank accession numbers of Fusarium strains used in the phylogenetic analyses.
Table 1. GenBank accession numbers of Fusarium strains used in the phylogenetic analyses.
SpeciesCulture Collection No./IsolateGenBank Accession
Fusarium carminascensCPC 144738 TMH484937MH485028MH485119
F. contaminatumCBS 111552 TMH484901MH484992MH485083
F. pharetrumCBS 144751 TMH484952MH485043MH485134
F. veterinariumCBS 109898 TMH484899MH484990MH485081
F. cugenangenseCBS 620.72MH484879MH484970MH485061
F. curvatumCBS 238.94 TMH484893MH484984MH485075
F. fabacearumCPC 25802 TMH484939MH485030MH485121
F. glycinesCBS 144746 TMH484942MH485033MH485124
F. gossypinumCBS 116613 TMH484909MH485000MH485091
F. languescensCBS 645.78 TMH484880MH484971MH485062
F. libertatisCPC 28465 TMH484944MH485035MH485126
F. nirenbergiaeCBS 840.88 TMH484887MH484978MH485069
F. oxysporumCBS 144134 ETMH484953MH485044MH485135
F. hoodiaeCBS 132474 TMH484929MH485020MH485111
F. duoseptatumCBS 102026 TMH484896MH484987MH485078
F. callistephiCBS 187.53 TMH484875MH484966MH485057
F. triseptatumCBS 258.50 TMH484910MH485001MH485055
F. languescensCBS 645.78 TMH484880MH484971MH485062
F. elaeidisCBS 217.49MH484870MH484961MH485052
F.acutatumCBS 402.97 TMW402768MW402125MW402323
F. agapanthiNRRL 54463 TKU900625KU900630KU900635
F. ananatumCBS 118516 TLT996137LT996091MN534089
F. andiyaziCBS 119857 TLT996138MN193854LT996113
F. annulatumCBS 258.54 TMT010983MT010994MT011041
F. anthophilumCBS 222.76 ETMW402811MW402114MW402312
F.bactridioidesCBS 100057 TMN534235MN533993MN534112
F. begoniaeCBS 452.97 TMN534243MN533994MN534101
F. brevicatenulatumCBS 404.97 TMN534295MN533995MN534063
F. bulbicolaCBS 220.76 TMW402767KF466415KF466437
F. chinhoyienseNRRL 25221 TMN534262MN534050MN534082
F. subglutinansCBS 747.97 NTMW402773MW402150MW402351
F. circinatumCBS 405.97 TMN534252MN533997MN534097
F. coicisNRRL 66233 TKP083274KP083251LT996115
F. concentricumCBS 450.97 TJF741086AF160282MW402334
F. globosumCBS 428.97 TKF466406KF466417MN534124
F. guttiformeCBS 409.97 TMT010967MT010999MT011048
F. konzumCBS 119849 TMW402733LT996098MN534095
F. lactisCBS 411.97 ETMN534275MN193862MN534077
F. longicornicolaNRRL 52706 TJF741114JF740788MW402360
F. denticulatumCBS 407.97 TMN534274MN534000MN534068
F. dlaminiiCBS 119860 TKU171701MW401995MW402195
F. fujikuroiCBS 221.76 TKU604255MN534010MN534130
F.madaenseCBS 146669 TMW402764MW402098MW402297
F.mangiferaeCBS 120994 TMN534271MN534017MN534128
F.mexicanumNRRL 53147 TMN724973GU737282GU737494
F.mundagurraRGB5717 TKP083276KP083256MN534146
F.musaeCBS 624.87 TMW402772FN552086FN545368
F. napiformeCBS 748.97 TMN534291MN193863MN534085
F. nygamaiCBS 749.97 TEF470114MW402151MW402352
F. phyllophilumCBS 216.76 TKF466410MN193864KF466443
F. pilosicolaNRRL 29124 TMN534248MN534055MN534099
F. proliferatumCBS 480.96 ETMN534272MN534059MN534129
F. pseudonygamaiCBS 417.97 TMN534285AF160263MN534066
F. ramigenumCBS 418.97 TKF466412KF466423MN534145
F. sacchariCBS 223.76 ETJX171580MW402115MW402313
F.siculiCBS 142222 TLT746327LT746214LT746346
F.succisaeCBS 219.76 ETMW402766AF160291U34419
F.sudanenseCBS 454.97 TMN534278MN534037MN534073
F.terricolaCBS 483.94 TLT996156MN534042MN534076
F.thapsinumCBS 776.96 TMN534289MN534044MN534080
F.tjaetabaNRRL 66243 TKP083275KP083263GU737296
F. tupienseNRRL 53984LR792619GU737404GU737296
F. prieskaenseCBS 146498 TMW834006MW834274MW834302
F. foetensCBS 110286 TMW928825MT011001MT011049
F. hostaeNRRL 29889 TMT409446MT409456AY329042
F. udumNRRL 25199 ETKY498875KY498862KY498892
F. stilboidesCBS 746.79 TMW928832MW928843-
F. buharicumNRRL 25488KX302928KX302912-
F. equisetiNRRL 26419-GQ505599-
NRRL 20697-GQ505594-
NRRL 13405 TGQ915491GQ915507GQ915441
F.peruvianumCBS 511.75-MN120767-
F. sarcochroumCBS 745.79JX171586MW834278-
F. inflexumNRRL 20433JX171583AF008479U34435
F. sublunatumNRRL 20897KX302935KX302919-
F. convolutansCBS 144207 TLT996141LT996094-
F. sarcochroumCBS 745.79-MW834278-
Macroconia leptosphaeriaeCBS 100001HQ728164KM231959KM232097
CBS: Westerdijk Fungal Biodiversity Institute (WIFB), Utrecht, The Netherlands. NRRL (Northern Regional Research Laboratory): Agricultural Research Service Culture Collection Database, Peoria, USA. CMW: The working collection of FABI (Forestry and Agricultural Biotechnology Institute), University of Pretoria, South Africa. BBA: Julius Kühn-Institute, Institute for Epidemiology and Pathogen Diagnostics, Berlin and Braunschweig, Germany. CPC: Collection of P.W. Crous. T: Ex-type specimen. NT: Neotype specimen. ET: Ex-epitype specimen. Accession numbers in bold belong to newly determined Dendrobium officinale isolates of Fusarium spp.
Table 2. Sampling details, number of isolates collected, and frequency of fungal species identified in the present study.
Table 2. Sampling details, number of isolates collected, and frequency of fungal species identified in the present study.
Geographic OriginSpeciesNo. IsolateIsolation Frequency (%)
Zhejiang Province (Yueqing City)F. concentricum5334.6
F. curvatum3422.3
F. fujikuroi2818.4
F. nirenbergiae2113.8
F. stilboides1610.5
Table 3. Virulence testing of Fusarium species on Pyrus pyrifolia.
Table 3. Virulence testing of Fusarium species on Pyrus pyrifolia.
SpeciesMean Lesion Size (mm) ± SD
F. concentricum45.30 a ± 3.19
F. fujikuroi41.83 b ± 1.84
F. nirenbergiae39.85 c ± 1.64
F. curvatum34.8 d ± 1.66
F. stilboides28.92 e ± 2.00
Note: The severity of the isolates was assessed by measuring the length of the fruit rot on P. pyrifolia at 7 DPI in two perpendicular directions. Data are mean ± SE. The mean values followed by different letters represent significantly different values at p < 0.05 among species using the least significant difference test (LSD).
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Mirghasempour, S.A.; Michailides, T.; Chen, W.; Mao, B. Fusarium spp. Associated with Dendrobium officinale Dieback Disease in China. J. Fungi 2022, 8, 919.

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Mirghasempour SA, Michailides T, Chen W, Mao B. Fusarium spp. Associated with Dendrobium officinale Dieback Disease in China. Journal of Fungi. 2022; 8(9):919.

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Mirghasempour, Seyed Ali, Themis Michailides, Weiliang Chen, and Bizeng Mao. 2022. "Fusarium spp. Associated with Dendrobium officinale Dieback Disease in China" Journal of Fungi 8, no. 9: 919.

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