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Sample records for canker fungus fusarium

  1. Visualization of wound periderm and hyphal profiles in pine stems inoculated with the pitch canker fungus Fusarium circinatum.

    PubMed

    Kim, Ki Woo; Lee, In Jung; Thoungchaleun, Vilakon; Kim, Chang Soo; Lee, Don Koo; Park, Eun Woo

    2009-12-01

    Postpenetration behavior of Fusarium circinatum in stems of pine species was investigated with light and transmission electron microscopy. Two-year-old stems of Pinus rigida and P. densiflora were wound-inoculated with the fungal conidial suspension and subjected to 25 degrees C for up to 30 days. It was common to observe the formation of wound periderm on each pine species, recovering wounded sites with newly formed tissues. The outermost thick layer of wound periderm was pink to red colored with the phloroglucinol-EtOH staining, indicating heavy deposition of lignin in wound periderm. The cork layers in the wound periderm of the two pine species consisted of cells that were mostly devoid of cellular contents in cytoplasm. The cork cells showed convoluted cell walls with different electron density (lamellations), which was seemingly more prevalent in P. densiflora than P. rigida. Hyphae of F. circinatum appeared normal with typical eucaryotic cytoplasm in P. rigida on ultrathin sections. Meanwhile, hyphae in P. densiflora were found to possess highly vacuolated cytoplasm, implying hyphal weakening and disintegration. Hyphal cytoplasm appeared to be a thin layer between the vacuole and the plasma membrane surrounded by cell wall. In addition, intrahyphal hyphae and concentric bodies were observed in hyphal cytoplasm. These results suggest that the architecture of wound periderm may be responsible for different responses of pine species to the invasion of F. circinatum.

  2. Adaptive Potential of Maritime Pine (Pinus pinaster) Populations to the Emerging Pitch Canker Pathogen, Fusarium circinatum

    PubMed Central

    Elvira-Recuenco, Margarita; Iturritxa, Eugenia; Majada, Juan; Alia, Ricardo; Raposo, Rosa

    2014-01-01

    There is a concern on how emerging pests and diseases will affect the distribution range and adaptability of their host species, especially due to different conditions derived from climate change and growing globalization. Fusarium circinatum, which causes pitch canker disease in Pinus species, is an exotic pathogen of recent introduction in Spain that threatens its maritime pine (P. pinaster) stands. To predict the impact this disease will have on the species, we examine host resistance traits and their genetic architecture. Resistance phenotyping was done in a clonal provenance/progeny trial, using three-year-old cuttings artificially inoculated with the pathogen and maintained under controlled environmental conditions. A total number of 670 ramets were assessed, distributed in 10 populations, with a total of 47 families, 2 to 5 half-sibs per family, and 3–7 ramets per clone. High genetic variation was found at the three hierarchical levels studied: population, family and clone, being both additive and non-additive effects important. Narrow-sense and broad-sense heritability estimates were relatively high, with respective values of 0.43–0.58 and 0.51–0.8, depending on the resistance traits measured (lesion length, lesion length rate, time to wilting, and survival). These values suggest the species' high capacity of evolutionary response to the F. circinatum pathogen. A population originated in Northern Spain was the most resistant, while another from Morocco was the most susceptible. The total number of plants that did not show lesion development or presented a small lesion (length<30 mm) was 224 out of 670, indicating a high proportion of resistant trees in the offspring within the analyzed populations. We found large differences among populations and considerable genetic variation within populations, which should allow, through natural or artificial selection, the successful adaptation of maritime pine to pitch canker disease. PMID:25500822

  3. Adaptive potential of maritime pine (Pinus pinaster) populations to the emerging pitch canker pathogen, Fusarium circinatum.

    PubMed

    Elvira-Recuenco, Margarita; Iturritxa, Eugenia; Majada, Juan; Alia, Ricardo; Raposo, Rosa

    2014-01-01

    There is a concern on how emerging pests and diseases will affect the distribution range and adaptability of their host species, especially due to different conditions derived from climate change and growing globalization. Fusarium circinatum, which causes pitch canker disease in Pinus species, is an exotic pathogen of recent introduction in Spain that threatens its maritime pine (P. pinaster) stands. To predict the impact this disease will have on the species, we examine host resistance traits and their genetic architecture. Resistance phenotyping was done in a clonal provenance/progeny trial, using three-year-old cuttings artificially inoculated with the pathogen and maintained under controlled environmental conditions. A total number of 670 ramets were assessed, distributed in 10 populations, with a total of 47 families, 2 to 5 half-sibs per family, and 3-7 ramets per clone. High genetic variation was found at the three hierarchical levels studied: population, family and clone, being both additive and non-additive effects important. Narrow-sense and broad-sense heritability estimates were relatively high, with respective values of 0.43-0.58 and 0.51-0.8, depending on the resistance traits measured (lesion length, lesion length rate, time to wilting, and survival). These values suggest the species' high capacity of evolutionary response to the F. circinatum pathogen. A population originated in Northern Spain was the most resistant, while another from Morocco was the most susceptible. The total number of plants that did not show lesion development or presented a small lesion (length<30 mm) was 224 out of 670, indicating a high proportion of resistant trees in the offspring within the analyzed populations. We found large differences among populations and considerable genetic variation within populations, which should allow, through natural or artificial selection, the successful adaptation of maritime pine to pitch canker disease.

  4. A novel Fusarium species causes a canker disease of the critically endangered conifer, Torreya taxifolia

    Technology Transfer Automated Retrieval System (TEKTRAN)

    A canker disease of Florida torreya (Torreya taxifolia), here designated CDFT, has been implicated in the decline of this critically endangered species in its native range of northern Florida and southeastern Georgia. In our current surveys of eight Florida torreya sites, cankers were present on all...

  5. Extracellular biosynthesis of silver nanoparticles using the fungus Fusarium semitectum

    SciTech Connect

    Basavaraja, S.; Balaji, S.D.; Lagashetty, Arunkumar; Rajasab, A.H.; Venkataraman, A.

    2008-05-06

    Development of environmental friendly procedures for the synthesis of metal nanoparticles through biological processes is evolving into an important branch of nanobiotechnology. In this paper, we report on the use of fungus 'Fusarium semitectum' for the extracellular synthesis of silver nanoparticles from silver nitrate solution (i.e. through the reduction of Ag{sup +} to Ag{sup 0}). Highly stable and crystalline silver nanoparticles are produced in solution by treating the filtrate of the fungus F. semitectum with the aqueous silver nitrate solution. The formations of nanoparticles are understood from the UV-vis and X-ray diffraction studies. Transmission electron microscopy of the silver particles indicated that they ranged in size from 10 to 60 nm and are mostly spherical in shape. Interestingly the colloidal suspensions of silver nanoparticles are stable for many weeks. Possible medicinal applications of these silver nanoparticles are envisaged.

  6. Complete Genome Sequence of a Novel Hypovirus from the Phytopathogenic Fungus Fusarium langsethiae

    PubMed Central

    Li, Pengfei; Chen, Xiaoguang; He, Hao; Qiu, Dewen

    2017-01-01

    ABSTRACT We describe a novel positive single-stranded RNA virus, termed Fusarium langsethiae hypovirus 1 (FlHV1), from the isolate AH32 of the phytopathogenic fungus Fusarium langsethiae. The properties of FlHV1 permit assignment to the genus Alphahypovirus in the family Hypoviridae. This is the first report of a mycovirus identified in F. langsethiae. PMID:28254984

  7. Npc1 is involved in sterol trafficking in the filamentous fungus Fusarium graminearum

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The ortholog of the human gene NPC1 was identified in the plant pathogenic, filamentous fungus Fusarium graminearum by shared amino acid sequence, protein domain structure and cellular localization of the mature fungal protein. The Fusarium Npc1 gene shares 34% amino acid sequence identity and 51% s...

  8. Functional characterization of candidate effector proteins identified from the wheat scab fungus Fusarium graminearum

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Fungal pathogens often produce certain small secreted cysteine-rich proteins (SSCPs) during pathogenesis that may function in triggering resistance or susceptibility in specific host plants. We have recently identified a total of 190 SSCPs encoded in the genome of the wheat scab fungus Fusarium gra...

  9. BIOTRANSFORMATION OF 2,4,6-TRINITROTOLUENE (TNT) BY A PLANT-ASSOCIATED FUNGUS FUSARIUM OXYSPORUM

    EPA Science Inventory

    The capability of a plant-associated fungus, Fusarium oxyvorum, to transform TNT in liquid cultures was investigated. TNT was transformed into 2-amino-4, 6-dinitrotoluene (2-A-DNT), 4-amino-2, 6-dinitrotoluene (4-A- DNT), and 2, 4-diamino-6-nitrotoluene (2, 4-DAT) via 2- and 4-hy...

  10. Functional analysis of the kinome of the wheat scab fungus Fusarium graminearum

    Technology Transfer Automated Retrieval System (TEKTRAN)

    As in many other eukaryotes, protein kinases play major regulatory roles in filamentous fungi. Although the genomes of numerous plant pathogenic fungi have been sequenced, systematic characterization of their kinomes has not been reported. The wheat scab fungus Fusarium graminearum has 116 putative ...

  11. Compartmentalized gene regulatory network of the pathogenic fungus Fusarium graminearum

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Head blight caused by Fusarium graminearum (Fg) is a major limiting factor of wheat production with both yield loss and mycotoxin contamination. Here we report a model for global Fg gene regulatory networks (GRNs) inferred from a large collection of transcriptomic data using a machine-learning appro...

  12. Characterization and host range of the symbiotic fungus Fusarium euwallaceae sp. nov., vectored by the invasive ambrosia beetle Euwallacea sp.

    Technology Transfer Automated Retrieval System (TEKTRAN)

    A novel symbiotic Fusarium euwallaceae fungus that serves as a specific nutritional source for the invasive Asian ambrosia beetle Euwallacea sp. (Coleoptera, Scolytinae, Xyleborini) is farmed in the galleries of host plants. This beetle-fungus complex, which has invaded Israel and California, is clo...

  13. Draft genome sequence of diaporthe aspalathi isolate ms-ssc91 a fungus causing stem canker in soybean

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Diaporthe aspalathi (formerly D. phaseolorum var. meridionalis) is the causal agent of the southern stem canker disease in soybean. This disease can kill plants from the middle to the end of the growing season resulting in severe yield loss. The mechanisms of disease development and pathogen invasi...

  14. Efficacy of female Culex quinquefasciatus with entomopathogenic fungus Fusarium pallidoroseum.

    PubMed

    Mohanty, Suman Sundar; Raghavendra, Kamaraju; Rai, Usha; Dash, Aditya Prasad

    2008-06-01

    This study was conducted to isolate and identify natural entomopathogenic fungi from female Culex quinquefasciatus and to test their adulticidal activity. Field-collected female C. quinquefasciatus died early and were placed on a Saboraud's dextrose agar plates for growth and isolation of natural entomopathogenic fungi. The plates were maintained in an incubator at 24+/-2 degrees C for 3 days. Four fungal species were isolated in two genera namely, Aspergillus and Fusarium. The identified fungal species were A. niger, A. flavus, A. nidulans var acristatus (ITCC-6327.04), and F. pallidoroseum (ITCC-6324.06). Adult bioassays were carried out using spore-impregnated paper in WHO-holding tubes. F. pallidoroseum was found to be more effective than the others. Exposure of C. quinquefasciatus to spores of A. flavus and A. niger for 4 h caused 5.53% and 5.51% mortality in the mosquitoes within a week, respectively. All the female C. quinquefasciatus were killed within 4 days of exposure to F. pallidoroseum at a concentration of 1.11 x 10(10) conidia per m2. Significant difference of longevity was observed between the F. pallidoroseum-treated C. quinquefasciatus and control mosquitoes. The LT50 of F. pallidoroseum was 2.08 days for 4 h exposure to C. quinquefasciatus. Results of the present study confirm that F. pallidoroseum is one of the alternative biological control agents of adult mosquitoes.

  15. The rhizosphere microbial community in a multiple parallel mineralization system suppresses the pathogenic fungus Fusarium oxysporum

    PubMed Central

    Fujiwara, Kazuki; Iida, Yuichiro; Iwai, Takashi; Aoyama, Chihiro; Inukai, Ryuya; Ando, Akinori; Ogawa, Jun; Ohnishi, Jun; Terami, Fumihiro; Takano, Masao; Shinohara, Makoto

    2013-01-01

    The rhizosphere microbial community in a hydroponics system with multiple parallel mineralization (MPM) can potentially suppress root-borne diseases. This study focused on revealing the biological nature of the suppression against Fusarium wilt disease, which is caused by the fungus Fusarium oxysporum, and describing the factors that may influence the fungal pathogen in the MPM system. We demonstrated that the rhizosphere microbiota that developed in the MPM system could suppress Fusarium wilt disease under in vitro and greenhouse conditions. The microbiological characteristics of the MPM system were able to control the population dynamics of F. oxysporum, but did not eradicate the fungal pathogen. The roles of the microbiological agents underlying the disease suppression and the magnitude of the disease suppression in the MPM system appear to depend on the microbial density. F. oxysporum that survived in the MPM system formed chlamydospores when exposed to the rhizosphere microbiota. These results suggest that the microbiota suppresses proliferation of F. oxysporum by controlling the pathogen's morphogenesis and by developing an ecosystem that permits coexistence with F. oxysporum. PMID:24311557

  16. The role of a dark septate endophytic fungus, Veronaeopsis simplex Y34, in Fusarium disease suppression in Chinese cabbage.

    PubMed

    Khastini, Rida O; Ohta, Hiroyuki; Narisawa, Kazuhiko

    2012-08-01

    The soil-inhabiting fungal pathogen Fusarium oxysporum has been an increasing threat to Chinese cabbage (Brassica campestris L.). A dark septate endophytic fungus, Veronaeopsis simplex Y34, isolated from Yaku Island, Japan, was evaluated in vitro for the ability to suppress Fusarium disease. Seedlings grown in the presence of the endophyte showed a 71% reduction in Fusarium wilt disease and still had good growth. The disease control was achieved through a synergetic effect involving a mechanical resistance created by a dense network of V. simplex Y34 hyphae, which colonized the host root, and siderophore production acting indirectly to induce a resistance mechanism in the plant. Changes in the relative abundance of the fungal communities in the soil as determined by fluorescently labelled T-RFs (terminal restriction fragments), appeared 3 weeks after application of the fungus. Results showed the dominance of V. simplex Y34, which became established in the rhizosphere and out-competed F. oxysporum.

  17. Molecular characterization of a novel hypovirus from the plant pathogenic fungus Fusarium graminearum.

    PubMed

    Li, Pengfei; Zhang, Hailong; Chen, Xiaoguang; Qiu, Dewen; Guo, Lihua

    2015-07-01

    A novel mycovirus, termed Fusarium graminearum Hypovirus 2 (FgHV2/JS16), isolated from a plant pathogenic fungus, Fusarium graminearum strain JS16, was molecularly and biologically characterized. The genome of FgHV2/JS16 is 12,800 nucleotides (nts) long, excluding the poly (A) tail. This genome has only one large putative open reading frame, which encodes a polyprotein containing three normal functional domains, papain-like protease, RNA-dependent RNA polymerase, RNA helicase, and a novel domain with homologous bacterial SMC (structural maintenance of chromosomes) chromosome segregation proteins. A defective RNA segment that is 4553-nts long, excluding the poly (A) tail, was also detected in strain JS16. The polyprotein shared significant aa identities with Cryphonectria hypovirus 1 (CHV1) (16.8%) and CHV2 (16.2%). Phylogenetic analyses based on multiple alignments of the polyprotein clearly divided the members of Hypoviridae into two major groups, suggesting that FgHV2/JS16 was a novel hypovirus of a newly proposed genus-Alphahypovirus-composed of the members of Group 1, including CHV1, CHV2, FgHV1 and Sclerotinia sclerotiorum hypovirus 2. FgHV2/JS16 was shown to be associated with hypovirulence phenotypes according to comparisons of the biological properties shared between FgHV2/JS16-infected and FgHV2/JS16-free isogenic strains. Furthermore, we demonstrated that FgHV2/JS16 infection activated the RNA interference pathway in Fusarium graminearum by relative quantitative real time RT-PCR.

  18. Fusaroside, a unique glycolipid from Fusarium sp., an endophytic fungus isolated from Melia azedarach.

    PubMed

    Yang, Sheng-Xiang; Wang, Hong-Peng; Gao, Jin-Ming; Zhang, Qiang; Laatsch, Hartmut; Kuang, Yi

    2012-01-28

    Fusaroside (1), a unique trehalose-containing glycolipid composed of the 4-hydroxyl group of a trehalose unit attached to the carboxylic carbon of a long-chain fatty acid, was isolated from the organic extract of fermentation broths of an endophytic fungus, Fusarium sp. LN-11 isolated from the leaves of Melia azedarach. Six known compounds, phalluside (2), (9R*,10R*,7E)-6, 9,10-trihydroxyoctadec-7-enoic acid (3), porrigenic acid (4), (9Z)-2,3-dihydroxypropyl octadeca-9-enoate (5), cerevisterol (6) and ergokonin B (7), were also isolated from this fungus. The glycolipid contains a rare branched long-chain fatty acid (C(20:4)) with a conjugated diene moiety and a conjugated ketone moiety. The structure of the new compound 1 was elucidated by spectroscopic methods (1D and 2D NMR experiments, MS) and chemical degradations. The metabolites 1-5 were shown to have moderate to weak active against the brine shrimp larvae. To our knowledge, this is the first report of isolation of the first representative of a new family of glycolipids from natural sources.

  19. Knock down of chitosanase expression in phytopathogenic fungus Fusarium solani and its effect on pathogenicity.

    PubMed

    Liu, Huaiwei; Zhang, Bo; Li, Changsong; Bao, Xiaoming

    2010-06-01

    Chitosanases are lytic enzymes involved in the degradation of chitosan, a component of fungal cell walls. The phytopathogenic fungus Fusarium solani produces an extracellular chitosanase, CSN1, the role of which in the physiology and virulence of the fungus remains to be expounded. Here, we studied the expression of the CSN1 gene through gene silencing and examined its effect on fungal pathogenicity. A vector construct encoding a hairpin RNA (hpRNA) of CSN1 was constructed and introduced into the F. solani 0114 strain. The results revealed that majority of the transformants exhibited a significant reduction in chitosanase activity compared with the wild-type strain. Further, transformants with silenced CSN1 exhibited no change in mycelial growth and spore formation. However, pea pod and seedling bioassays indicated that transformants with silenced CSN1 were more virulent compared with the wild-type strain, and in sharp contrast to strains in which overexpression of the CSN1 gene resulted in virulence reduction. Although the mechanism remains unclear, our findings did suggest that F. solani chitosanase has a negative effect on fungal pathogenicity.

  20. Pitch canker disease of pines.

    PubMed

    Gordon, T R

    2006-06-01

    ABSTRACT Pitch canker, caused by Fusarium circinatum, is a disease affecting pines in many locations throughout the world. The pathosystem was originally described in the southeastern (SE) United States and was identified in California in 1986. Limited vegetative compatibility group (VCG) diversity in the California population of F. circinatum, relative to the SE United States, suggests the former is a recently established and clonally propagating population. Although the much greater VCG diversity found in the SE United States is suggestive of out-crossing, molecular markers indicate that many vegetatively incompatible isolates are clonally related. This implies that VCG diversity may derive, at least in part, from somatic mutations rather than sexual reproduction. Pitch canker is damaging to many pine species and one at particular risk is Monterey pine (Pinus radiata), which is widely grown in plantations and is highly susceptible to pitch canker. However, some Monterey pines are resistant to pitch canker and some severely diseased trees have been observed to recover. The absence of new infections on these trees reflects the operation of systemic induced resistance, apparently in response to repeated infection by the pitch canker pathogen.

  1. Canker Sores

    MedlinePlus

    Canker sores are small, round sores in your mouth. They can be on the inside of your cheek, under your tongue, or in the back of your throat. They usually have a red edge and a gray center. They can be quite painful. They are ...

  2. Taxol production by an endophytic fungus, Fusarium redolens, isolated from Himalayan yew.

    PubMed

    Garyali, Sanjog; Kumar, Anil; Reddy, M Sudhakara

    2013-10-28

    Different endophytic fungi isolated from Himalayan Yew plants were tested for their ability to produce taxol. The BAPT gene (C-13 phenylpropanoid side chain-CoA acetyl transferase) involved in the taxol biosynthetic pathway was used as a molecular marker to screen taxol-producing endophytic fungi. Taxol extracted from fungal strain TBPJ-B was identified by HPLC and MS analysis. Strain TBPJ-B was identified as Fusarium redolens based on the morphology and internal transcribed spacer region of nrDNA analysis. HPLC quantification of fungal taxol showed that F. redolens was capable of producing 66 μg/l of taxol in fermentation broth. The antitumour activity of the fungal taxol was tested by potato disc tumor induction assay using Agrobacterium tumefaciens as the tumor induction agent. The present study results showed that PCR amplification of genes involved in taxol biosynthesis is an efficient and reliable method for prescreening taxol-producing fungi. We are reporting for the first time the production of taxol by F. redolens from Taxus baccata L. subsp. wallichiana (Zucc.) Pilger. This study offers important information and a new source for the production of the important anticancer drug taxol by endophytic fungus fermentation.

  3. First Record of Fusarium verticillioides as an Entomopathogenic Fungus of Grasshoppers

    PubMed Central

    Pelizza, SA; Stenglein, SA; Cabello, MN; Dinolfo, MI; Lange, CE

    2011-01-01

    Fusarium verticillioides (Saccardo) Nirenberg (Ascomycota: Hypocreales) is the most common fungus reported on infected corn kernels and vegetative tissues, but has not yet been documented as being entomopathogenic for grasshoppers. Grasshoppers and locusts represent a large group of insects that cause economic damage to forage and crops. Tropidacris collaris (Stoll) (Orthoptera: Acridoidea: Romaleidae) is a large and voracious grasshopper that in recent years has become an increasingly recurrent and widespread pest in progressively more greatly extended areas of some of in Argentina's northern provinces, with chemical insecticides being currently the only means of control. During February and March of 2008–09, nymphs and adults of T. collaris were collected with sweep nets in dense woodland vegetation at a site near Tres Estacas in western Chaco Province, Argentina, and kept in screened cages. F. verticillioides was isolated from insects that died within 10 days and was cultured in PGA medium. Pathogenicity tests were conducted and positive results recorded. Using traditional and molecular-biological methods, an isolate of F. verticillioides was obtained from T. collaris, and its pathogenecity in the laboratory was shown against another harmful grasshopper, Ronderosia bergi (Stål) (Acridoidea: Acrididae: Melanoplinae). The mortality caused by F. verticillioides on R. bergi reached 58 ± 6.53% by 10 days after inoculation. This is the first record of natural infection caused by F. verticillioides in grasshoppers. PMID:21867437

  4. First record of Fusarium verticillioides as an entomopathogenic fungus of grasshoppers.

    PubMed

    Pelizza, S A; Stenglein, S A; Cabello, M N; Dinolfo, M I; Lange, C E

    2011-01-01

    Fusarium verticillioides (Saccardo) Nirenberg (Ascomycota: Hypocreales) is the most common fungus reported on infected corn kernels and vegetative tissues, but has not yet been documented as being entomopathogenic for grasshoppers. Grasshoppers and locusts represent a large group of insects that cause economic damage to forage and crops. Tropidacris collaris (Stoll) (Orthoptera: Acridoidea: Romaleidae) is a large and voracious grasshopper that in recent years has become an increasingly recurrent and widespread pest in progressively more greatly extended areas of some of in Argentina's northern provinces, with chemical insecticides being currently the only means of control. During February and March of 2008-09, nymphs and adults of T. collaris were collected with sweep nets in dense woodland vegetation at a site near Tres Estacas in western Chaco Province, Argentina, and kept in screened cages. F. verticillioides was isolated from insects that died within 10 days and was cultured in PGA medium. Pathogenicity tests were conducted and positive results recorded. Using traditional and molecular-biological methods, an isolate of F. verticillioides was obtained from T. collaris, and its pathogenecity in the laboratory was shown against another harmful grasshopper, Ronderosia bergi (Stål) (Acridoidea: Acrididae: Melanoplinae). The mortality caused by F. verticillioides on R. bergi reached 58 ± 6.53% by 10 days after inoculation. This is the first record of natural infection caused by F. verticillioides in grasshoppers.

  5. Dynamics of Cryphonectria hypovirus infection in chestnut blight cankers.

    PubMed

    Bryner, Sarah Franziska; Prospero, Simone; Rigling, Daniel

    2014-09-01

    Virulent strains of the chestnut blight fungus Cryphonectria parasitica cause lethal bark cankers on chestnut trees. Infection of C. parasitica with Cryphonectria hypovirus 1 in Europe biologically controls this disease, leading to nonlethal and inactive cankers. Unexpectedly, virus-free C. parasitica strains have been isolated from inactive cankers. In this study, we compared the virulence of virus-infected and virus-free C. parasitica strains isolated from either inactive or active cankers on chestnut seedlings and sprouts. In the seedling experiment, we assessed canker growth and seedling mortality. In the sprout experiment, we also assessed canker growth and made fungal reisolations to determine virus infection and immigration of foreign vegetative compatibility (vc) types over a period of 13 years in a coppice forest. Overall, the virulence of virus-free C. parasitica strains isolated from inactive versus active cankers did not differ. Significant differences were only attributed to virus infection. Virus infection and fungal strain composition in cankers changed over time. Foreign vc types immigrated into cankers and virus-free cankers became virus-infected within a few years. Most of the cankers were callused over time and became inactive. However, we observed that the virus did not always persist in these cankers. This study demonstrates that virus spread occurs effectively in European chestnut forests and that this biocontrol system is highly dynamic.

  6. Two novel Fusarium species that cause canker disease of Sichuan pepper (Zanthoxylum bungeanum Maxim.) in northern China form a novel clade with F. torreyae

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Canker disease of prickly ash (Zanthoxylum bungeanum) has caused a decline in the production of this economically important spice in northern China in the past 25 y. To identify the etiological agent, 38 fungal isolates were recovered from symptomatic tissues from trees in five provinces in China. T...

  7. The Predicted Secretome of the Plant Pathogenic Fungus Fusarium graminearum: A Refined Comparative Analysis

    PubMed Central

    Brown, Neil A.; Antoniw, John; Hammond-Kosack, Kim E.

    2012-01-01

    The fungus Fusarium graminearum forms an intimate association with the host species wheat whilst infecting the floral tissues at anthesis. During the prolonged latent period of infection, extracellular communication between live pathogen and host cells must occur, implying a role for secreted fungal proteins. The wheat cells in contact with fungal hyphae subsequently die and intracellular hyphal colonisation results in the development of visible disease symptoms. Since the original genome annotation analysis was done in 2007, which predicted the secretome using TargetP, the F. graminearum gene call has changed considerably through the combined efforts of the BROAD and MIPS institutes. As a result of the modifications to the genome and the recent findings that suggested a role for secreted proteins in virulence, the F. graminearum secretome was revisited. In the current study, a refined F. graminearum secretome was predicted by combining several bioinformatic approaches. This strategy increased the probability of identifying truly secreted proteins. A secretome of 574 proteins was predicted of which 99% was supported by transcriptional evidence. The function of the annotated and unannotated secreted proteins was explored. The potential role(s) of the annotated proteins including, putative enzymes, phytotoxins and antifungals are discussed. Characterisation of the unannotated proteins included the analysis of Pfam domains and features associated with known fungal effectors, for example, small size, cysteine-rich and containing internal amino acid repeats. A comprehensive comparative genomic analysis involving 57 fungal and oomycete genomes revealed that only a small number of the predicted F. graminearum secreted proteins can be considered to be either species or sequenced strain specific. PMID:22493673

  8. Detoxification of the Fusarium toxin fusaric acid by the soil fungus Aspergillus

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The fungal pathogen Fusarium oxysporum f. sp. vasinfectum (Fov) causes Fusarium wilt in cotton (Gossypium hirsutum L.) and produces the toxin fusaric acid (FA). Previous research indicates that in the high producing strains of Fov, FA plays an important role in virulence. To address the problems o...

  9. Acid and neutral trehalase activities in mutants of the corn rot fungus Fusarium verticillioides

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Fusarium verticillioides is a fungal pathogen known to cause corn rot and other plant diseases and to contaminate grain with toxic metabolites. We are characterizing trehalose metabolism in F. verticillioides with the hope that this pathway might serve as a target for controlling Fusarium disease. T...

  10. The genome of the of the generalist plant pathogenic fungus Fusarium avenaceum is enriched with genes involved in redox, signaling and secondary metabolism

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Fusarium avenaceum is a fungus commonly isolated from soil and with a wide range of host plants. We present here three genome sequences of F. avenaceum, one isolated from barley in Finland and two from spring and winter wheat in Canada. The physical sizes of the three genomes range from 41.6-43.2 MB...

  11. Biological control of Cucurbita pepo var texana (Texas gourd) in cotton (Gossypium hirsutum) with the fungus Fusarium solani f sp Cucurbitae

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Experiments were conducted to evaluate various formulations and application methods of the fungus Fusarium solani f. sp. cucurbitae (FSC) for controlling Texas gourd (Cucurbita pepo var. texana) in cotton (Gosssypium hirsutum). In greenhouse tests, Texas gourd was controlled 93% and 96%, respective...

  12. Widespread occurrence of diverse human pathogenic types of the fungus Fusarium detected in plumbing drains.

    PubMed

    Short, Dylan P G; O'Donnell, Kerry; Zhang, Ning; Juba, Jean H; Geiser, David M

    2011-12-01

    It has been proposed that plumbing systems might serve as a significant environmental reservoir of human-pathogenic isolates of Fusarium. We tested this hypothesis by performing the first extensive multilocus sequence typing (MLST) survey of plumbing drain-associated Fusarium isolates and comparing the diversity observed to the known diversity of clinical Fusarium isolates. We sampled 471 drains, mostly in bathroom sinks, from 131 buildings in the United States using a swabbing method. We found that 66% of sinks and 80% of buildings surveyed yielded at least one Fusarium culture. A total of 297 isolates of Fusarium collected were subjected to MLST to identify the phylogenetic species and sequence types (STs) of these isolates. Our survey revealed that the six most common STs in sinks were identical to the six most frequently associated with human infections. We speculate that the most prevalent STs, by virtue of their ability to form and grow in biofilms, are well adapted to plumbing systems. Six major Fusarium STs were frequently isolated from plumbing drains within a broad geographic area and were identical to STs frequently associated with human infections.

  13. The fibrinolytic activity of a novel protease derived from a tempeh producing fungus, Fusarium sp. BLB.

    PubMed

    Sugimoto, Satoshi; Fujii, Tadashi; Morimiya, Tatsuo; Johdo, Osamu; Nakamura, Takumi

    2007-09-01

    Tempeh is a traditional Indonesian soybean-fermented food produced by filamentous fungi, Rhizopus sp. and Fusarium sp. We isolated and sequenced the genomic gene and a cDNA clone encoding a novel protease (FP) from Fusarium sp. BLB. The genomic gene was 856 bp in length and contained two introns. An isolated cDNA clone encoded a protein of 250 amino acids. The predicted amino acid sequence of FP showed highest homology, of 76%, with that of trypsin from Fusarium oxysporum. The hydrolysis activity of FP toward synthetic peptide was higher than that of any other protease tested, including Nattokinases. Furthermore, the thrombolytic activity of FP was about 2.1-fold higher than that of Nattokinase when the concentration of plasminogen was 24 units/ml. These results suggest that FP is superior to Nattokinases in dissolving fibrin when absorbed into the blood.

  14. Progress report on a contemporary survey of the Fusarium wilt fungus in the United States

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The last survey of Fusarium oxysporum f. sp. vasinfectum in the U.S. was conducted in 1985. Since that time, race 4, previously thought to occur only in Asia, appeared in California in 2001, causing significant problems for the San Joaquin Valley cotton industry. Also, the presence of race 8 has bee...

  15. Genome sequence of Fusarium oxysporum f. sp. melonis, a fungus causing wilt disease on melon

    Technology Transfer Automated Retrieval System (TEKTRAN)

    This manuscript reports the genome sequence of F. oxysporum f. sp. melonis, a fungal pathogen that causes Fusarium wilt disease on melon (Cucumis melo). The project is part of a large comparative study designed to explore the genetic composition and evolutionary origin of this group of horizontally ...

  16. Genome Sequence of Fusarium oxysporum f. sp. melonis, a fungus causing wilt disease on melon

    Technology Transfer Automated Retrieval System (TEKTRAN)

    This manuscript reports the genome sequence of F. oxysporum f. sp. melonis, a fungal pathogen that causes Fusarium wilt disease on melon (Cucumis melo). The project is part of a large comparative study designed to explore the genetic composition and evolutionary origin of this group of horizontally ...

  17. Draft Genome Sequence of Phytopathogenic Fungus Fusarium fujikuroi CF-295141, Isolated from Pinus sylvestris

    PubMed Central

    Bertoni-Mann, Michele; Sánchez-Hidalgo, Marina; González-Menéndez, Victor

    2016-01-01

    Here, we report the draft genome sequence of a new strain of Fusarium fujikuroi, isolated from Pinus sylvestris, which was also found to produce the mycotoxin beauvericin. The Illumina-based sequence analysis revealed an approximate genome size of 44.2 Mbp, containing 164 secondary metabolite biosynthetic clusters. PMID:27795279

  18. FgFlbD regulates hyphal differentiation required for sexual and asexual reproduction in the ascomycete fungus Fusarium graminearum.

    PubMed

    Son, Hokyoung; Kim, Myung-Gu; Chae, Suhn-Kee; Lee, Yin-Won

    2014-11-01

    Fusarium graminearum is a filamentous fungal plant pathogen that infects major cereal crops. The fungus produces both sexual and asexual spores in order to endure unfavorable environmental conditions and increase their numbers and distribution across plants. In a model filamentous fungus, Aspergillus nidulans, early induction of conidiogenesis is orchestrated by the fluffy genes. The objectives of this study were to characterize fluffy gene homologs involved in conidiogenesis and their mechanism of action in F. graminearum. We characterized five fluffy gene homologs in F. graminearum and found that FlbD is the only conserved regulator for conidiogenesis in A. nidulans and F. graminearum. Deletion of fgflbD prevented hyphal differentiation and the formation of perithecia. Successful interspecies complementation using A. nidulans flbD demonstrated that the molecular mechanisms responsible for FlbD functions are conserved in F. graminearum. Moreover, abaA-wetA pathway is positively regulated by FgFlbD during conidiogenesis in F. graminearum. Deleting fgflbD abolished morphological effects of abaA overexpression, which suggests that additional factors for FgFlbD or an AbaA-independent pathway for conidiogenesis are required for F. graminearum conidiation. Importantly, this study led to the construction of a genetic pathway of F. graminearum conidiogenesis and provides new insights into the genetics of conidiogenesis in fungi.

  19. Plant tissue colonization by the fungus race 1.2 of Fusarium oxysporum f.sp. melonis in resistant melon genotypes.

    PubMed

    Chikh-Rouhou, H; González-Torres, R; Alvarez, M

    2009-01-01

    Four melon accessions; 'Shiroubi Okayoma', 'C-211', 'K.N.M' and 'BG-5384', resistant to race 1.2 of Fusarium oxysporum f.sp. melonis and a susceptible one 'Piel de Sapo' were tested to see which hypocotyl regions were invaded by the fungus, and to examine the relationship between resistance and presence of the pathogen in the plant tissue. While the fungus was shown to colonize all stem segments (either the upper, middle, or lower hypocotyl) of the susceptible and resistant plant accession, colonization was markedly lower in the resistant plants.

  20. The Wor1-like Protein Fgp1 Regulates Pathogenicity, Toxin Synthesis and Reproduction in the Phytopathogenic Fungus Fusarium graminearum

    PubMed Central

    Jonkers, Wilfried; Dong, Yanhong; Broz, Karen; Corby Kistler, H.

    2012-01-01

    WOR1 is a gene for a conserved fungal regulatory protein controlling the dimorphic switch and pathogenicity determents in Candida albicans and its ortholog in the plant pathogen Fusarium oxysporum, called SGE1, is required for pathogenicity and expression of key plant effector proteins. F. graminearum, an important pathogen of cereals, is not known to employ switching and no effector proteins from F. graminearum have been found to date that are required for infection. In this study, the potential role of the WOR1-like gene in pathogenesis was tested in this toxigenic fungus. Deletion of the WOR1 ortholog (called FGP1) in F. graminearum results in greatly reduced pathogenicity and loss of trichothecene toxin accumulation in infected wheat plants and in vitro. The loss of toxin accumulation alone may be sufficient to explain the loss of pathogenicity to wheat. Under toxin-inducing conditions, expression of genes for trichothecene biosynthesis and many other genes are not detected or detected at lower levels in Δfgp1 strains. FGP1 is also involved in the developmental processes of conidium formation and sexual reproduction and modulates a morphological change that accompanies mycotoxin production in vitro. The Wor1-like proteins in Fusarium species have highly conserved N-terminal regions and remarkably divergent C-termini. Interchanging the N- and C- terminal portions of proteins from F. oxysporum and F. graminearum resulted in partial to complete loss of function. Wor1-like proteins are conserved but have evolved to regulate pathogenicity in a range of fungi, likely by adaptations to the C-terminal portion of the protein. PMID:22693448

  1. Hexacyclopeptides secreted by an endophytic fungus Fusarium solani N06 act as crosstalk molecules in Narcissus tazetta.

    PubMed

    Wang, Wen-Xuan; Kusari, Souvik; Sezgin, Selahaddin; Lamshöft, Marc; Kusari, Parijat; Kayser, Oliver; Spiteller, Michael

    2015-09-01

    The basis of chemical crosstalk in plants and associated endophytes lies in certain so-called communication molecules that are responsible for plant-microbe and microbe-microbe interactions. Consequently, elucidating the factors that affect the nature, distribution, and amount of these molecules and how they impact the interaction among endophytes and associated organisms is essential to understand the true potential of endophytes. In the present study, we report the discovery of nine hexacyclopeptides from an endophytic fungus, Fusarium solani, isolated from the bulb of Narcissus tazetta, and their selective accumulation by an endophytic bacterium, Achromobacter xylosoxidans isolated from the same tissue. We used matrix-assisted laser desorption ionization imaging high-resolution mass spectrometry (MALDI-imaging-HRMS) to firstly identify and visualize the spatial distribution of the hexacyclopeptides produced by endophytic F. solani. After culture condition optimization, their sequence was identified to be cyclo((Hyp or Dhp)-Xle-Xle-(Ala or Val)-Thr-Xle) (Dhp: dehydroproline) by the characteristic a, b, or y ions using liquid chromatography tandem mass spectrometry (LC-HRMS(n)). These hexacyclopeptides were confirmed to be fungal biosynthetic products by deuterium labeling experiments. Finally, in order to understand the plausible ecological relevance of one or more of the discovered hexacyclopeptides within the contexts of microbial "neighbor communication," we devised a dual-culture setup to visualize using MALDI-imaging-HRMS how the hexacyclopeptides released by the endophytic fungus are accumulated by another endophytic bacterium, A. xylosoxidans, isolated from the same bulb tissue. This work exemplifies the relevance of cyclopeptides in endophyte-endophyte interspecies neighbor communication occurring in nature. Such communication strategies are evolved by coexisting endophytes to survive and function in their distinct ecological niches.

  2. Enhancement of diosgenin production in Dioscorea zingiberensis cell cultures by oligosaccharides from its endophytic fungus Fusarium oxysporum Dzf17.

    PubMed

    Li, Peiqin; Mao, Ziling; Lou, Jingfeng; Li, Yan; Mou, Yan; Lu, Shiqiong; Peng, Youliang; Zhou, Ligang

    2011-12-19

    The effects of the oligosaccharides from the endophytic fungus Fusarium oxysporum Dzf17 as elicitors on diosgenin production in cell suspension cultures of its host Dioscorea zingiberensis were investigated. Three oligosaccharides, DP4, DP7 and DP10, were purified from the oligosaccharide fractions DP2-5, DP5-8 and DP8-12, respectively, which were prepared from the water-extracted mycelial polysaccharide of the endophytic fungus F. oxysporum Dzf17. When the cell cultures were treated with fraction DP5-8 at 20 mg/L on day 26 and harvested on day 32, the maximum diosgenin yield (2.187 mg/L) was achieved, which was 5.65-fold of control (0.387 mg/L). When oligosaccharides DP4, DP7 and DP10 were individually added to 26-day-old D. zingiberensis cell cultures at concentrations of 2, 4, 6, 8 and 10 mg/L in medium, DP7 at 6 mg/L was found to significantly enhance diosgenin production, with a yield of 3.202 mg/L, which was 8.27-fold of control. When the cell cultures were treated with DP7 twice on days 24 and 26, and harvested on day 30, both diosgenin content and yield were significantly increased and reached the maximums of 1.159 mg/g dw and 4.843 mg/L, both of which were higher than those of single elicitation, and were 9.19- and 12.38-fold of control, respectively.

  3. Extracellular biosynthesis of CdTe quantum dots by the fungus Fusarium oxysporum and their anti-bacterial activity

    NASA Astrophysics Data System (ADS)

    Syed, Asad; Ahmad, Absar

    2013-04-01

    The growing demand for semiconductor [quantum dots (Q-dots)] nanoparticles has fuelled significant research in developing strategies for their synthesis and characterization. They are extensively investigated by the chemical route; on the other hand, use of microbial sources for biosynthesis witnessed the highly stable, water dispersible nanoparticles formation. Here we report, for the first time, an efficient fungal-mediated synthesis of highly fluorescent CdTe quantum dots at ambient conditions by the fungus Fusarium oxysporum when reacted with a mixture of CdCl2 and TeCl4. Characterization of these biosynthesized nanoparticles was carried out by different techniques such as Ultraviolet-visible (UV-Vis) spectroscopy, Photoluminescence (PL), X-ray Diffraction (XRD), X-ray Photoelectron spectroscopy (XPS), Transmission Electron Microscopy (TEM) and Fourier Transformed Infrared Spectroscopy (FTIR) analysis. CdTe nanoparticles shows antibacterial activity against Gram positive and Gram negative bacteria. The fungal based fabrication provides an economical, green chemistry approach for production of highly fluorescent CdTe quantum dots.

  4. Extraction optimization of water-extracted mycelial polysaccharide from endophytic fungus Fusarium oxysporum Dzf17 by response surface methodology.

    PubMed

    Li, Peiqin; Lu, Shiqiong; Shan, Tijiang; Mou, Yan; Li, Yan; Sun, Weibo; Zhou, Ligang

    2012-01-01

    Water-extracted mycelial polysaccharide (WPS) from the endophytic fungus Fusarium oxysporum Dzf17 isolated from Dioscorea zingiberensis was found to be an efficient elicitor to enhance diosgenin accumulation in D. zingigerensis cultures, and also demonstrated antioxidant activity. In this study, response surface methodology (RSM) was employed to optimize the extraction process of WPS from F. oxysporum Dzf17 using Box-Behnken design (BBD). The ranges of the factors investigated were 1-3 h for extraction time (X(1)), 80-100 °C for extraction temperature (X(2)), and 20-40 (v/w) for ratio of water volume (mL) to raw material weight (g) (X(3)). The experimental data obtained were fitted to a second-order polynomial equation using multiple regression analysis. Statistical analysis showed that the polynomial regression model was in good agreement with the experimental results with the determination coefficient (R(2)) of 0.9978. By solving the regression equation and analyzing the response surface contour plots, the extraction parameters were optimized as 1.7 h for extraction time, 95 °C for extraction temperature, 39 (v/w) for ratio of water volume (mL) to raw material weight (g), and with 2 extractions. The maximum value (10.862%) of WPS yield was obtained when the WPS extraction process was conducted under the optimal conditions.

  5. Extraction Optimization of Water-Extracted Mycelial Polysaccharide from Endophytic Fungus Fusarium oxysporum Dzf17 by Response Surface Methodology

    PubMed Central

    Li, Peiqin; Lu, Shiqiong; Shan, Tijiang; Mou, Yan; Li, Yan; Sun, Weibo; Zhou, Ligang

    2012-01-01

    Water-extracted mycelial polysaccharide (WPS) from the endophytic fungus Fusarium oxysporum Dzf17 isolated from Dioscorea zingiberensis was found to be an efficient elicitor to enhance diosgenin accumulation in D. zingigerensis cultures, and also demonstrated antioxidant activity. In this study, response surface methodology (RSM) was employed to optimize the extraction process of WPS from F. oxysporum Dzf17 using Box-Behnken design (BBD). The ranges of the factors investigated were 1–3 h for extraction time (X1), 80–100 °C for extraction temperature (X2), and 20–40 (v/w) for ratio of water volume (mL) to raw material weight (g) (X3). The experimental data obtained were fitted to a second-order polynomial equation using multiple regression analysis. Statistical analysis showed that the polynomial regression model was in good agreement with the experimental results with the determination coefficient (R2) of 0.9978. By solving the regression equation and analyzing the response surface contour plots, the extraction parameters were optimized as 1.7 h for extraction time, 95 °C for extraction temperature, 39 (v/w) for ratio of water volume (mL) to raw material weight (g), and with 2 extractions. The maximum value (10.862%) of WPS yield was obtained when the WPS extraction process was conducted under the optimal conditions. PMID:22754306

  6. Silver nanoparticle production by the fungus Fusarium oxysporum: nanoparticle characterisation and analysis of antifungal activity against pathogenic yeasts

    PubMed Central

    Ishida, Kelly; Cipriano, Talita Ferreira; Rocha, Gustavo Miranda; Weissmüller, Gilberto; Gomes, Fabio; Miranda, Kildare; Rozental, Sonia

    2013-01-01

    The microbial synthesis of nanoparticles is a green chemistry approach that combines nanotechnology and microbial biotechnology. The aim of this study was to obtain silver nanoparticles (SNPs) using aqueous extract from the filamentous fungus Fusarium oxysporum as an alternative to chemical procedures and to evaluate its antifungal activity. SNPs production increased in a concentration-dependent way up to 1 mM silver nitrate until 30 days of reaction. Monodispersed and spherical SNPs were predominantly produced. After 60 days, it was possible to observe degenerated SNPs with in additional needle morphology. The SNPs showed a high antifungal activity against Candida and Cryptococcus , with minimum inhibitory concentration values ≤ 1.68 µg/mL for both genera. Morphological alterations of Cryptococcus neoformans treated with SNPs were observed such as disruption of the cell wall and cytoplasmic membrane and lost of the cytoplasm content. This work revealed that SNPs can be easily produced by F. oxysporum aqueous extracts and may be a feasible, low-cost, environmentally friendly method for generating stable and uniformly sized SNPs. Finally, we have demonstrated that these SNPs are active against pathogenic fungi, such as Candida and Cryptococcus . PMID:24714966

  7. Silver nanoparticle production by the fungus Fusarium oxysporum: nanoparticle characterisation and analysis of antifungal activity against pathogenic yeasts.

    PubMed

    Ishida, Kelly; Cipriano, Talita Ferreira; Rocha, Gustavo Miranda; Weissmüller, Gilberto; Gomes, Fabio; Miranda, Kildare; Rozental, Sonia

    2014-04-01

    The microbial synthesis of nanoparticles is a green chemistry approach that combines nanotechnology and microbial biotechnology. The aim of this study was to obtain silver nanoparticles (SNPs) using aqueous extract from the filamentous fungus Fusarium oxysporum as an alternative to chemical procedures and to evaluate its antifungal activity. SNPs production increased in a concentration-dependent way up to 1 mM silver nitrate until 30 days of reaction. Monodispersed and spherical SNPs were predominantly produced. After 60 days, it was possible to observe degenerated SNPs with in additional needle morphology. The SNPs showed a high antifungal activity against Candida and Cryptococcus , with minimum inhibitory concentration values ≤ 1.68 µg/mL for both genera. Morphological alterations of Cryptococcus neoformans treated with SNPs were observed such as disruption of the cell wall and cytoplasmic membrane and lost of the cytoplasm content. This work revealed that SNPs can be easily produced by F. oxysporum aqueous extracts and may be a feasible, low-cost, environmentally friendly method for generating stable and uniformly sized SNPs. Finally, we have demonstrated that these SNPs are active against pathogenic fungi, such as Candida and Cryptococcus.

  8. A MAP kinase of the vascular wilt fungus Fusarium oxysporum is essential for root penetration and pathogenesis.

    PubMed

    Di Pietro, A; García-MacEira, F I; Méglecz, E; Roncero, M I

    2001-03-01

    The soil-borne vascular wilt fungus Fusarium oxysporum infects a wide variety of plant species by directly penetrating roots, invading the cortex and colonizing the vascular tissue. We have identified fmk1, encoding a mitogen-activated protein kinase (MAPK) of F. oxysporum that belongs to the yeast and fungal extracellular signal-regulated kinase (YERK1) subfamily. Targeted mutants of F. oxysporum f. sp. lycopersici carrying an inactivated copy of fmk1 have lost pathogenicity on tomato plants but show normal vegetative growth and conidiation in culture. Colonies of the fmk1 mutants are easily wettable, and hyphae are impaired in breaching the liquid-air interface, suggesting defects in surface hydrophobicity. Fmk1 mutants also show reduced invasive growth on tomato fruit tissue and drastically reduced transcript levels of pl1 encoding the cell wall-degrading enzyme pectate lyase. Conidia of the mutants germinating in the tomato rhizosphere fail to differentiate penetration hyphae, resulting in greatly impaired root attachment. The orthologous MAPK gene Pmk1 from the rice leaf pathogen Magnaporthe grisea complements invasive growth and partially restores surface hydrophobicity, root attachment and pathogenicity in an fmk1 mutant. These results demonstrate that FMK1 controls several key steps in the pathogenesis of F. oxysporum and suggest a fundamentally conserved role for the corresponding MAPK pathway in soil-borne and foliar plant pathogens.

  9. Transcriptomic profiling to identify genes involved in Fusarium mycotoxin Deoxynivalenol and Zearalenone tolerance in the mycoparasitic fungus Clonostachys rosea

    PubMed Central

    2014-01-01

    Background Clonostachys rosea strain IK726 is a mycoparasitic fungus capable of controlling mycotoxin-producing Fusarium species, including F. graminearum and F. culmorum, known to produce Zearalenone (ZEA) and Deoxynivalenol (DON). DON is a type B trichothecene known to interfere with protein synthesis in eukaryotes. ZEA is a estrogenic-mimicing mycotoxin that exhibits antifungal growth. C. rosea produces the enzyme zearalenone hydrolase (ZHD101), which degrades ZEA. However, the molecular basis of resistance to DON in C. rosea is not understood. We have exploited a genome-wide transcriptomic approach to identify genes induced by DON and ZEA in order to investigate the molecular basis of mycotoxin resistance C. rosea. Results We generated DON- and ZEA-induced cDNA libraries based on suppression subtractive hybridization. A total of 443 and 446 sequenced clones (corresponding to 58 and 65 genes) from the DON- and ZEA-induced library, respectively, were analysed. DON-induced transcripts represented genes encoding metabolic enzymes such as cytochrome P450, cytochrome c oxidase and stress response proteins. In contrast, transcripts encoding the ZEA-detoxifying enzyme ZHD101 and those encoding a number of ATP-Binding Cassette (ABC) transporter transcripts were highly frequent in the ZEA-induced library. Subsequent bioinformatics analysis predicted that all transcripts with similarity to ABC transporters could be ascribed to only 2 ABC transporters genes, and phylogenetic analysis of the predicted ABC transporters suggested that they belong to group G (pleiotropic drug transporters) of the fungal ABC transporter gene family. This is the first report suggesting involvement of ABC transporters in ZEA tolerance. Expression patterns of a selected set of DON- and ZEA-induced genes were validated by the use of quantitative RT-PCR after exposure to the toxins. The qRT-PCR results obtained confirm the expression patterns suggested from the EST redundancy data. Conclusion The

  10. Canker Sores (For Parents)

    MedlinePlus

    ... Lessons? Visit KidsHealth in the Classroom What Other Parents Are Reading Your Child's Development (Birth to 3 Years) Feeding Your 1- to 3-Month-Old Feeding Your 4- to 7-Month-Old Feeding Your 8- to 12-Month-Old Feeding Your 1- to 2-Year-Old Canker ... > For Parents > Canker Sores Print A A A What's in ...

  11. RNA-seq Transcriptome Response of Flax (Linum usitatissimum L.) to the Pathogenic Fungus Fusarium oxysporum f. sp. lini

    PubMed Central

    Galindo-González, Leonardo; Deyholos, Michael K.

    2016-01-01

    Fusarium oxysporum f. sp. lini is a hemibiotrophic fungus that causes wilt in flax. Along with rust, fusarium wilt has become an important factor in flax production worldwide. Resistant flax cultivars have been used to manage the disease, but the resistance varies, depending on the interactions between specific cultivars and isolates of the pathogen. This interaction has a strong molecular basis, but no genomic information is available on how the plant responds to attempted infection, to inform breeding programs on potential candidate genes to evaluate or improve resistance across cultivars. In the current study, disease progression in two flax cultivars [Crop Development Center (CDC) Bethune and Lutea], showed earlier disease symptoms and higher susceptibility in the later cultivar. Chitinase gene expression was also divergent and demonstrated and earlier molecular response in Lutea. The most resistant cultivar (CDC Bethune) was used for a full RNA-seq transcriptome study through a time course at 2, 4, 8, and 18 days post-inoculation (DPI). While over 100 genes were significantly differentially expressed at both 4 and 8 DPI, the broadest deployment of plant defense responses was evident at 18 DPI with transcripts of more than 1,000 genes responding to the treatment. These genes evidenced a reception and transduction of pathogen signals, a large transcriptional reprogramming, induction of hormone signaling, activation of pathogenesis-related genes, and changes in secondary metabolism. Among these, several key genes that consistently appear in studies of plant-pathogen interactions, had increased transcript abundance in our study, and constitute suitable candidates for resistance breeding programs. These included: an induced RPMI-induced protein kinase; transcription factors WRKY3, WRKY70, WRKY75, MYB113, and MYB108; the ethylene response factors ERF1 and ERF14; two genes involved in auxin/glucosinolate precursor synthesis (CYP79B2 and CYP79B3); the flavonoid

  12. WetA Is Required for Conidiogenesis and Conidium Maturation in the Ascomycete Fungus Fusarium graminearum

    PubMed Central

    Son, Hokyoung; Kim, Myung-Gu; Min, Kyunghun; Lim, Jae Yun; Choi, Gyung Ja; Kim, Jin-Cheol; Chae, Suhn-Kee

    2014-01-01

    Fusarium graminearum, a prominent fungal pathogen that infects major cereal crops, primarily utilizes asexual spores to spread disease. To understand the molecular mechanisms underlying conidiogenesis in F. graminearum, we functionally characterized the F. graminearum ortholog of Aspergillus nidulans wetA, which has been shown to be involved in conidiogenesis and conidium maturation. Deletion of F. graminearum wetA did not alter mycelial growth, sexual development, or virulence, but the wetA deletion mutants produced longer conidia with fewer septa, and the conidia were sensitive to acute stresses, such as oxidative stress and heat stress. Furthermore, the survival rate of aged conidia from the F. graminearum wetA deletion mutants was reduced. The wetA deletion resulted in vigorous generation of single-celled conidia through autophagy-dependent microcycle conidiation, indicating that WetA functions to maintain conidial dormancy by suppressing microcycle conidiation in F. graminearum. Transcriptome analyses demonstrated that most of the putative conidiation-related genes are expressed constitutively and that only a few genes are specifically involved in F. graminearum conidiogenesis. The conserved and distinct roles identified for WetA in F. graminearum provide new insights into the genetics of conidiation in filamentous fungi. PMID:24186953

  13. How Phytohormones Shape Interactions between Plants and the Soil-Borne Fungus Fusarium oxysporum

    PubMed Central

    Di, Xiaotang; Takken, Frank L. W.; Tintor, Nico

    2016-01-01

    Plants interact with a huge variety of soil microbes, ranging from pathogenic to mutualistic. The Fusarium oxysporum (Fo) species complex consists of ubiquitous soil inhabiting fungi that can infect and cause disease in over 120 different plant species including tomato, banana, cotton, and Arabidopsis. However, in many cases Fo colonization remains symptomless or even has beneficial effects on plant growth and/or stress tolerance. Also in pathogenic interactions a lengthy asymptomatic phase usually precedes disease development. All this indicates a sophisticated and fine-tuned interaction between Fo and its host. The molecular mechanisms underlying this balance are poorly understood. Plant hormone signaling networks emerge as key regulators of plant-microbe interactions in general. In this review we summarize the effects of the major phytohormones on the interaction between Fo and its diverse hosts. Generally, Salicylic Acid (SA) signaling reduces plant susceptibility, whereas Jasmonic Acid (JA), Ethylene (ET), Abscisic Acid (ABA), and auxin have complex effects, and are potentially hijacked by Fo for host manipulation. Finally, we discuss how plant hormones and Fo effectors balance the interaction from beneficial to pathogenic and vice versa. PMID:26909099

  14. Biosynthesis of Gold Nanoparticles Using Fusarium oxysporum f. sp. cubense JT1, a Plant Pathogenic Fungus

    PubMed Central

    Thakker, Janki N.; Dalwadi, Pranay; Dhandhukia, Pinakin C.

    2013-01-01

    The development of reliable processes for the synthesis of gold nanoparticles is an important aspect of current nanotechnology research. Recently, reports are published on the extracellular as well as intracellular biosynthesis of gold nanoparticles using microorganisms. However, these methods of synthesis are rather slow. In present study, rapid and extracellular synthesis of gold nanoparticles using a plant pathogenic fungus F. oxysporum f. sp. cubense JT1 (FocJT1) is reported. Incubation of FocJT1 mycelium with auric chloride solution produces gold nanoparticles in 60 min. Gold nanoparticles were characterized by UV-Vis spectroscopy, FTIR, and particle size analysis. The particles synthesized were of 22 nm sized, capped by proteins, and posed antimicrobial activity against Pseudomonas sp. PMID:25969773

  15. Genome-wide exonic small interference RNA-mediated gene silencing regulates sexual reproduction in the homothallic fungus Fusarium graminearum

    PubMed Central

    Park, Ae Ran; Lim, Jae Yun; Shin, Chanseok

    2017-01-01

    Various ascomycete fungi possess sex-specific molecular mechanisms, such as repeat-induced point mutations, meiotic silencing by unpaired DNA, and unusual adenosine-to-inosine RNA editing, for genome defense or gene regulation. Using a combined analysis of functional genetics and deep sequencing of small noncoding RNA (sRNA), mRNA, and the degradome, we found that the sex-specifically induced exonic small interference RNA (ex-siRNA)-mediated RNA interference (RNAi) mechanism has an important role in fine-tuning the transcriptome during ascospore formation in the head blight fungus Fusarium graminearum. Approximately one-third of the total sRNAs were produced from the gene region, and sRNAs with an antisense direction or 5′-U were involved in post-transcriptional gene regulation by reducing the stability of the corresponding gene transcripts. Although both Dicers and Argonautes partially share their functions, the sex-specific RNAi pathway is primarily mediated by FgDicer1 and FgAgo2, while the constitutively expressed RNAi components FgDicer2 and FgAgo1 are responsible for hairpin-induced RNAi. Based on our results, we concluded that F. graminearum primarily utilizes ex-siRNA-mediated RNAi for ascosporogenesis but not for genome defenses and other developmental stages. Each fungal species appears to have evolved RNAi-based gene regulation for specific developmental stages or stress responses. This study provides new insights into the regulatory role of sRNAs in fungi and other lower eukaryotes. PMID:28146558

  16. Insights from the fungus Fusarium oxysporum point to high affinity glucose transporters as targets for enhancing ethanol production from lignocellulose.

    PubMed

    Ali, Shahin S; Nugent, Brian; Mullins, Ewen; Doohan, Fiona M

    2013-01-01

    Ethanol is the most-widely used biofuel in the world today. Lignocellulosic plant biomass derived from agricultural residue can be converted to ethanol via microbial bioprocessing. Fungi such as Fusarium oxysporum can simultaneously saccharify straw to sugars and ferment sugars to ethanol. But there are many bottlenecks that need to be overcome to increase the efficacy of microbial production of ethanol from straw, not least enhancement of the rate of fermentation of both hexose and pentose sugars. This research tested the hypothesis that the rate of sugar uptake by F. oxysporum would enhance the ethanol yields from lignocellulosic straw and that high affinity glucose transporters can enhance ethanol yields from this substrate. We characterized a novel hexose transporter (Hxt) from this fungus. The F. oxysporum Hxt represents a novel transporter with homology to yeast glucose signaling/transporter proteins Rgt2 and Snf3, but it lacks their C-terminal domain which is necessary for glucose signalling. Its expression level decreased with increasing glucose concentration in the medium and in a glucose uptake study the Km((glucose)) was 0.9 mM, which indicated that the protein is a high affinity glucose transporter. Post-translational gene silencing or over expression of the Hxt in F. oxysporum directly affected the glucose and xylose transport capacity and ethanol yielded by F. oxysporum from straw, glucose and xylose. Thus we conclude that this Hxt has the capacity to transport both C5 and C6 sugars and to enhance ethanol yields from lignocellulosic material. This study has confirmed that high affinity glucose transporters are ideal candidates for improving ethanol yields from lignocellulose because their activity and level of expression is high in low glucose concentrations, which is very common during the process of consolidated processing.

  17. Host extract modulates metabolism and fumonisin biosynthesis by the plant-pathogenic fungus Fusarium proliferatum.

    PubMed

    Stępień, Łukasz; Waśkiewicz, Agnieszka; Wilman, Karolina

    2015-01-16

    Fusarium proliferatum is a common pathogen able to infect a broad range of agriculturally important crops. Recently, some evidence for genetic variance among the species genotypes in relation to their plant origin has been reported. Mycotoxin contamination of plant tissues is the most important threat caused by F. proliferatum and fumonisins B (FBs) are the principal mycotoxins synthesized. The toxigenic potential of the pathogen genotypes is variable and also the reaction of different host plant species on the infection by pathogen is different. The objective of present study was to evaluate the impact of the extracts on the growth and fumonisin biosynthesis by 32 F. proliferatum strains originating from different host species (A-asparagus, M-maize, G-garlic, PS-pea and P-pineapple), and how it changes the secondary metabolism measured by fumonisin biosynthesis. The average strain dry weight was 65.2 mg for control conditions and it reached 180.7 mg, 100.5 mg, 76.6 mg, 126.2 mg and 51.1 mg when pineapple, asparagus, maize, garlic and pea extracts were added, respectively. In the second experiment the extracts were added after 5 days of culturing of the representative group of strains, displaying diverse reaction to the extract presence. Also, the influence of stationary vs. shaken culture was examined. Mean biomass amounts for shaken cultures of 15 chosen strains were as follows: 37.4 mg of dry weight for control culture (C), 219.6 mg (P), 113 mg (A), 93.6 mg (M), 62 mg (G) and 48 mg (PS), respectively. For stationary cultures, the means were as follows: C-57.4 mg, P-355.6 mg, A-291.6 mg, M-191.1 mg, G-171.1 mg and PS-58.9 mg. Few strains showed differential growth when stationary/shaken culture conditions were applied. Almost all strains synthesized moderate amounts of fumonisins in control conditions-less than 10 ng/μL, regardless of the origin and host species. Few strains were able to produce over 100 ng/μL of FBs when pineapple extract was added, twelve

  18. Studies on the management of root-knot nematode, Meloidogyne incognita-wilt fungus, Fusarium oxysporum disease complex of green gram, Vigna radiata cv ML-1108

    PubMed Central

    Haseeb, Akhtar; Sharma, Anita; Shukla, Prabhat Kuma

    2005-01-01

    Studies were conducted under pot conditions to determine the comparative efficacy of carbofuran at 1 mg a.i./kg soil, bavistin at 1 mg a.i./kg soil, neem (Azadirachta indica) seed powder at 50 mg/kg soil, green mould (Trichoderma harzianum) at 50.0 ml/kg soil, rhizobacteria (Pseudomonas fluorescens) at 50.0 ml/kg soil against root-knot nematode, Meloidogyne incognita–wilt fungus, Fusarium oxysporum disease complex on green gram, Vigna radiata cv ML-1108. All the treatments significantly improved the growth of the plants as compared to untreated inoculated plants. Analysis of data showed that carbofuran and A. indica seed powder increased plant growth and yield significantly more in comparison to bavistin and P. fluorescens. Carbofuran was highly effective against nematode, bavistin against fungus, A. indica seed powder against both the pathogens and both the bioagents were moderately effective against both the pathogens. PMID:16052706

  19. Genome Sequence of Fusarium oxysporum f. sp. melonis Strain NRRL 26406, a Fungus Causing Wilt Disease on Melon

    PubMed Central

    Shea, Terrance; Young, Sarah; Zeng, Qiandong; Kistler, H. Corby

    2014-01-01

    Horizontal chromosome transfer introduces host-specific pathogenicity among members of the Fusarium oxysporum species complex and is responsible for some of the most destructive and intractable plant diseases. This paper reports the genome sequence of F. oxysporum f. sp. melonis (NRRL 26406), a causal agent of Fusarium wilt disease on melon. PMID:25081257

  20. One Fungus, One Name: Defining the genus Fusarium in a scientifically robust way that preserves longstanding use

    Technology Transfer Automated Retrieval System (TEKTRAN)

    In this letter, we advocate recognizing the genus Fusarium as the sole name for a group that includes virtually all Fusarium species of importance in plant pathology, mycotoxicology, medicine and basic research. This phylogenetically-guided circumscription will free scientists from any obligation to...

  1. TaFROG Encodes a Pooideae Orphan Protein That Interacts with SnRK1 and Enhances Resistance to the Mycotoxigenic Fungus Fusarium graminearum.

    PubMed

    Perochon, Alexandre; Jianguang, Jia; Kahla, Amal; Arunachalam, Chanemougasoundharam; Scofield, Steven R; Bowden, Sarah; Wallington, Emma; Doohan, Fiona M

    2015-12-01

    All genomes encode taxonomically restricted orphan genes, and the vast majority are of unknown function. There is growing evidence that such genes play an important role in the environmental adaptation of taxa. We report the functional characterization of an orphan gene (Triticum aestivum Fusarium Resistance Orphan Gene [TaFROG]) as a component of resistance to the globally important wheat (T. aestivum) disease, Fusarium head blight. TaFROG is taxonomically restricted to the grass subfamily Pooideae. Gene expression studies showed that it is a component of the early wheat response to the mycotoxin deoxynivalenol (DON), which is a virulence factor produced by the causal fungal agent of Fusarium head blight, Fusarium graminearum. The temporal induction of TaFROG by F. graminearum in wheat spikelets correlated with the activation of the defense Triticum aestivum Pathogenesis-Related-1 (TaPR1) gene. But unlike TaPR1, TaFROG induction by F. graminearum was toxin dependent, as determined via comparative analysis of the effects of wild-type fungus and a DON minus mutant derivative. Using virus-induced gene silencing and overexpressing transgenic wheat lines, we present evidence that TaFROG contributes to host resistance to both DON and F. graminearum. TaFROG is an intrinsically disordered protein, and it localized to the nucleus. A wheat alpha subunit of the Sucrose Non-Fermenting1-Related Kinase1 was identified as a TaFROG-interacting protein based on a yeast two-hybrid study. In planta bimolecular fluorescence complementation assays confirmed the interaction. Thus, we conclude that TaFROG encodes a new Sucrose Non-Fermenting1-Related Kinase1-interacting protein and enhances biotic stress resistance.

  2. Different Culture Metabolites of the Red Sea Fungus Fusarium equiseti Optimize the Inhibition of Hepatitis C Virus NS3/4A Protease (HCV PR)

    PubMed Central

    Hawas, Usama W.; Al-Farawati, Radwan; Abou El-Kassem, Lamia T.; Turki, Adnan J.

    2016-01-01

    The endophytic fungus Fusarium equiseti was isolated from the brown alga Padina pavonica, collected from the Red Sea. The fungus was identified by its morphology and 18S rDNA. Cultivation of this fungal strain in biomalt-peptone medium led to isolation of 12 known metabolites of diketopeprazines and anthraquinones. The organic extract and isolated compounds were screened for their inhibition of hepatitis C virus NS3/4A protease (HCV PR). As a result, the fungal metabolites showed inhibition of HCV protease (IC50 from 19 to 77 μM), and the fungus was subjected to culture on Czapek’s (Cz) media, with a yield of nine metabolites with potent HCV protease inhibition ranging from IC50 10 to 37 μM. The Cz culture extract exhibited high-level inhibition of HCV protease (IC50 27.6 μg/mL) compared to the biomalt culture extract (IC50 56 μg/mL), and the most potent HCV PR isolated compound (Griseoxanthone C, IC50 19.8 μM) from the bio-malt culture extract showed less of an inhibitory effect compared to isolated ω-hydroxyemodin (IC50 10.7 μM) from the optimized Cz culture extract. Both HCV PR active inhibitors ω-hydroxyemodin and griseoxanthone C were considered as the lowest selective safe constituents against Trypsin inhibitory effect with IC50 48.5 and 51.3 μM, respectively. PMID:27775589

  3. Energy-dependent uptake of benzo[a]pyrene and its cytoskeleton-dependent intracellular transport by the telluric fungus Fusarium solani.

    PubMed

    Fayeulle, Antoine; Veignie, Etienne; Slomianny, Christian; Dewailly, Etienne; Munch, Jean-Charles; Rafin, Catherine

    2014-03-01

    In screening indigenous soil filamentous fungi for polycyclic aromatic hydrocarbons (PAHs) degradation, an isolate of the Fusarium solani was found to incorporate benzo[a]pyrene (BaP) into fungal hyphae before degradation and mineralization. The mechanisms involved in BaP uptake and intracellular transport remain unresolved. To address this, the incorporation of two PAHs, BaP, and phenanthrene (PHE) were studied in this fungus. The fungus incorporated more BaP into cells than PHE, despite the 400-fold higher aqueous solubility of PHE compared with BaP, indicating that PAH incorporation is not based on a simple diffusion mechanism. To identify the mechanism of BaP incorporation and transport, microscopic studies were undertaken with the fluorescence probes Congo Red, BODIPY®493/503, and FM®4-64, targeting different cell compartments respectively fungal cell walls, lipids, and endocytosis. The metabolic inhibitor sodium azide at 100 mM totally blocked BaP incorporation into fungal cells indicating an energy-requirement for PAH uptake into the mycelium. Cytochalasins also inhibited BaP uptake by the fungus and probably its intracellular transport into fungal hyphae. The perfect co-localization of BaP and BODIPY reveals that lipid bodies constitute the intracellular storage sites of BaP in F. solani. Our results demonstrate an energy-dependent uptake of BaP and its cytoskeleton-dependent intracellular transport by F. solani.

  4. Cytochrome p450nor, a novel class of mitochondrial cytochrome P450 involved in nitrate respiration in the fungus Fusarium oxysporum.

    PubMed

    Takaya, N; Suzuki, S; Kuwazaki, S; Shoun, H; Maruo, F; Yamaguchi, M; Takeo, K

    1999-12-15

    Fusarium oxysporum, an imperfect filamentous fungus performs nitrate respiration under limited oxygen. In the respiratory system, Cytochrome P450nor (P450nor) is thought to catalyze the last step; reduction of nitric oxide to nitrous oxide. We examined its intracellular localization using enzymatic, spectroscopic, and immunological analyses to show that P450nor is found in both the mitochondria and the cytosol. Translational fusions between the putative mitochondrial targeting signal on the amino terminus of P450nor and Escherichia coli beta-galactosidase resulted in significant beta-galactosidase activity in the mitochondrial fraction of nitrate-respiring cells, suggesting that one of the isoforms of P450nor (P450norA) is in anaerobic mitochondrion of F. oxysporum and acts as nitric oxide reductase. Furthermore, these findings suggest the involvement of P450nor in nitrate respiration in mitochondria.

  5. Fusarium euwallaceae sp. nov.—a symbiotic fungus of Euwallacea sp., an invasive ambrosia beetle in Israel and California

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The invasive Asian ambrosia beetle Euwallacea sp. (Coleoptera, Scolytinae, Xyleborini) and a novel Fusarium sp. that it farms in its galleries as a source of nutrition seriously damage over 20 species of live trees and pose a serious threat to avocado production (Persea americana) in Israel and Cali...

  6. The arbuscular mycorrhizal fungus, Glomus irregulare, controls the mycotoxin production of Fusarium sambucinum in the pathogenesis of potato

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Trichothecenes are an important family of mycotoxins produced by several species of the genus Fusarium. These fungi cause serious disease on infected plants and postharvest storage of crops and the toxins can cause health problems for humans and animals. Unfortunately, there are few methods for cont...

  7. The Wor1-like protein Fgp1 regulates pathogenicity, toxin synthesis and reproduction in the phytopathogenic fungus Fusarium graminearum

    Technology Transfer Automated Retrieval System (TEKTRAN)

    WOR1 is a gene for a conserved fungal regulatory protein controlling the dimorphic switch and pathogenicity in Candida albicans and its ortholog in the plant pathogen Fusarium oxysporum, called SGE1, is also required for pathogenicity and expression of plant effector proteins. F. graminearum, an imp...

  8. [Influence of antitumor preparations on the concentration of free radicals in cells of Fusarium bulbigenum var. blasticola fungus during primary and tumour-like secondary growth].

    PubMed

    Riabikin, Iu A; Nikitina, E T; Balgimbatva, A S; Zashkvara, O V; Shakiev, S Sh

    2007-01-01

    The fungus Fusarium bulbigenum var. blasticola in which secondary tumor-like formations appear under certain conditions in aging was used as a new test system to examine the action of antitumor preparations. Free radicals in the primary mycelium and tumor-like formations without introduction of preparations (control samples) and after the introduction of preparation into the cultivation medium of the fungus have been studied by EPR spectroscopy. The EPR spectra of the fungus represent single, somewhat asymmetrical lines with a width of deltaH = 0.4 divided by 0.6 mT and g = 2.0036 +/- 0.006, which enabled one to assign the paramagnetic centers observed to melanine radicals. It was found that the concentration of free radicals in tumor-like formations is always higher than in the primary mycelium, which may be related to intensive metabolism in tumor-like formations. It has been established that several antitumor preparations (fluorouracil, hydrea, methotrexat, and vepezide) completely inhibit the growth of tumor-like formations. Another group of preparations (cyclophosphanum, dacarbazin, adriablastin, and vinblastin), on the contrary, stimulate their growth, which is accompanied by an increase in the concentration of free radicals in cells of the primary mycelium and tumor-like formations. The preparations of the third group (mercaptopurine, lanvis, and farmorubicin), despite the increased level of free radicals in cells, have a weak inhibitory effect. It has been shown that, in the concentration range studied, vitamins B2, B12, C, and PP stimulate the growth of tumor-like formations, and, when used in combination with antitumor preparations, enhance or reduce the inhibitory properties of these preparations.

  9. Fusarium euwallaceae sp. nov.--a symbiotic fungus of Euwallacea sp., an invasive ambrosia beetle in Israel and California.

    PubMed

    Freeman, S; Sharon, M; Maymon, M; Mendel, Z; Protasov, A; Aoki, T; Eskalen, A; O'Donnell, K

    2013-01-01

    The invasive Asian ambrosia beetle Euwallacea sp. (Coleoptera, Scolytinae, Xyleborini) and a novel Fusarium sp. that it farms in its galleries as a source of nutrition causes serious damage to more than 20 species of live trees and pose a serious threat to avocado production (Persea americana) in Israel and California. Adult female beetles are equipped with mandibular mycangia in which its fungal symbiont is transported within and from the natal galleries. Damage caused to the xylem is associated with disease symptoms that include sugar or gum exudates, dieback, wilt and ultimately host tree mortality. In 2012 the beetle was recorded on more than 200 and 20 different urban landscape species in southern California and Israel respectively. Euwallacea sp. and its symbiont are closely related to the tea shot-hole borer (E. fornicatus) and its obligate symbiont, F. ambrosium occurring in Sri Lanka and India. To distinguish these beetles, hereafter the unnamed xyleborine in Israel and California will be referred to as Euwallacea sp. IS/CA. Both fusaria exhibit distinctive ecologies and produce clavate macroconidia, which we think might represent an adaption to the species-specific beetle partner. Both fusaria comprise a genealogically exclusive lineage within Clade 3 of the Fusarium solani species complex (FSSC) that can be differentiated with arbitrarily primed PCR. Currently these fusaria can be distinguished only phenotypically by the abundant production of blue to brownish macroconidia in the symbiont of Euwallacea sp. IS/CA and their rarity or absence in F. ambrosium. We speculate that obligate symbiosis of Euwallacea and Fusarium, might have driven ecological speciation in these mutualists. Thus, the purpose of this paper is to describe and illustrate the novel, economically destructive avocado pathogen as Fusarium euwallaceae sp. nov. S. Freeman et al.

  10. Multiple garlic (Allium sativum L.) microRNAs regulate the immunity against the basal rot fungus Fusarium oxysporum f. sp. Cepae.

    PubMed

    Chand, Subodh Kumar; Nanda, Satyabrata; Mishra, Rukmini; Joshi, Raj Kumar

    2017-04-01

    The basal plate rot fungus, Fusarium oxysporum f. sp. cepae (FOC), is the most devastating pathogen posing a serious threat to garlic (Allium sativum L.) production worldwide. MicroRNAs (miRNAs) are key modulators of gene expression related to development and defense responses in eukaryotes. However, the miRNA species associated with garlic immunity against FOC are yet to be explored. In the present study, a small RNA library developed from FOC infected resistant garlic line was sequenced to identify immune responsive miRNAs. Forty-five miRNAs representing 39 conserved and six novel sequences responsive to FOC were detected. qRT-PCR analyses further classified them into three classes based on their expression patterns in susceptible line CBT-As11 and in the resistant line CBT-As153. North-blot analyses of six selective miRNAs confirmed the qRT-PCR results. Expression studies on a selective set of target genes revealed a negative correlation with the complementary miRNAs. Furthermore, transgenic garlic plant overexpresing miR164a, miR168a and miR393 showed enhanced resistance to FOC, as revealed by decreased fungal growth and up-regulated expression of defense-responsive genes. These results indicate that multiple miRNAs are involved in garlic immunity against FOC and that the overexpression of miR164a, miR168a and miR393 can augment garlic resistance to Fusarium basal rot infection.

  11. Management of apple anthracnose canker

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Apple anthracnose (caused by Neofabraea malicorticis anamorph Cryptosporiopsis curvispora) is a fungal disease that causes cankers on trees and ‘Bull’s-eye rot’ on fruit. In western Washington, it is the canker phase of apple anthracnose that is considered most serious as it can result in death of ...

  12. Banana infecting fungus, Fusarium musae, is also an opportunistic human pathogen: are bananas potential carriers and source of fusariosis?

    PubMed

    Triest, David; Stubbe, Dirk; De Cremer, Koen; Piérard, Denis; Detandt, Monique; Hendrickx, Marijke

    2015-01-01

    During re-identification of Fusarium strains in the BCCM™/IHEM fungal collection by multilocus sequence-analysis we observed that five strains, previously identified as Fusarium verticillioides, were Fusarium musae, a species described in 2011 from banana fruits. Four strains were isolated from blood samples or biopsies of immune-suppressed patients and one was isolated from the clinical environment, all originating from different hospitals in Belgium or France, 2001-2008. The F. musae identity of our isolates was confirmed by phylogenetic analysis using reference sequences of type material. Absence of the gene cluster necessary for fumonisin biosynthesis, characteristic to F. musae, was also the case for our isolates. In vitro antifungal susceptibility testing revealed no important differences in their susceptibility compared to clinical F. verticillioides strains and terbinafine was the most effective drug. Additional clinical F. musae strains were searched by performing BLAST queries in GenBank. Eight strains were found, of which six were keratitis cases from the U.S. multistate contact lens-associated outbreak in 2005 and 2006. The two other strains were also from the U.S., causing either a skin infection or sinusitis. This report is the first to describe F. musae as causative agent of superficial and opportunistic, disseminated infections in humans. Imported bananas might act as carriers of F. musae spores and be a potential source of infection with F. musae in humans. An alternative hypothesis is that the natural distribution of F. musae is geographically a lot broader than originally suspected and F. musae is present on different plant hosts.

  13. Thorium(IV) removal from aqueous medium by citric acid treated mangrove endophytic fungus Fusarium sp. #ZZF51.

    PubMed

    Yang, S K; Tan, N; Yan, X M; Chen, F; Long, W; Lin, Y C

    2013-09-15

    Thorium(IV) biosorption is investigated by citric acid treated mangrove endophytic fungus Fussarium sp. #ZZF51 (CA-ZZF51) from South China Sea. The biosorption process was optimized at pH 4.5, equilibrium time 90 min, initial thorium(IV) concentration 50 mg L(-1) and adsorbent dose 0.6 g L(-1) with 90.87% of removal efficiency and 75.47 mg g(-1) of adsorption capacity, which is obviously greater than that (11.35 mg g(-1)) of the untreated fungus Fussarium sp. #ZZF51 for thorium(IV) biosorption under the condition of optimization. The experimental data are analyzed by using isotherm and kinetic models. Kinetic data follow the pseudo-second-order model and equilibrium data agree very well with the Langmuir model. In addition, FTIR analysis indicates that hydroxyl, amino, and carbonyl groups act as the important roles in the adsorption process.

  14. The CarO rhodopsin of the fungus Fusarium fujikuroi is a light-driven proton pump that retards spore germination

    PubMed Central

    García-Martínez, Jorge; Brunk, Michael; Avalos, Javier; Terpitz, Ulrich

    2015-01-01

    Rhodopsins are membrane-embedded photoreceptors found in all major taxonomic kingdoms using retinal as their chromophore. They play well-known functions in different biological systems, but their roles in fungi remain unknown. The filamentous fungus Fusarium fujikuroi contains two putative rhodopsins, CarO and OpsA. The gene carO is light-regulated, and the predicted polypeptide contains all conserved residues required for proton pumping. We aimed to elucidate the expression and cellular location of the fungal rhodopsin CarO, its presumed proton-pumping activity and the possible effect of such function on F. fujikuroi growth. In electrophysiology experiments we confirmed that CarO is a green-light driven proton pump. Visualization of fluorescent CarO-YFP expressed in F. fujikuroi under control of its native promoter revealed higher accumulation in spores (conidia) produced by light-exposed mycelia. Germination analyses of conidia from carO− mutant and carO+ control strains showed a faster development of light-exposed carO− germlings. In conclusion, CarO is an active proton pump, abundant in light-formed conidia, whose activity slows down early hyphal development under light. Interestingly, CarO-related rhodopsins are typically found in plant-associated fungi, where green light dominates the phyllosphere. Our data provide the first reliable clue on a possible biological role of a fungal rhodopsin. PMID:25589426

  15. Microbiological transformation of two 15α-hydroxy-ent-kaur-9(11),16-diene derivatives by the fungus Fusarium fujikuroi.

    PubMed

    Fraga, Braulio M; González-Vallejo, Victoria; Guillermo, Ricardo; Amaro-Luis, Juan M

    2013-05-01

    The incubation of 15α-hydroxy-ent-kaur-9(11),16-dien-19-oic acid (15α-hydroxy-grandiflorenic acid) with the fungus Fusarium fujikuroi gave as main metabolite its 3β,6β-dihydroxy derivative, which by an oxidative decarboxylation afforded a 19-nor compound with a 4,18-double bond. Other substances obtained were a 3α-hydroxy-19,6α-lactone, 3β-hydroxy-6β,7β-epoxy-ent-kaur-9(11),16-dien-19-oic acid and 3β-hydroxy-6-oxo-ent-kaur-9(11),16-dien-19-oic acid. Moreover, the biotransformation of 15α,18-dihydroxy-ent-kaur-9(11),16-diene led to the isolation of the corresponding 3β-, 6β-, 7α- and 12β-hydroxy derivatives. Two metabolites formed by 16β,17-epoxidation of the last compound and of the substrate were also obtained. These results indicated that the presence of the 9,11-double bond in the substrate impedes its 7β-hydroxylation, which is necessary for the formation of gibberellins and seco-ring B ent-kaurenoids. However, this 9,11-unsaturation does not hinder a 6,7-dehydrogenation and further 6β,7β-epoxidation, characteristic steps of the kaurenolide biosynthetic pathway.

  16. Tomato I2 Immune Receptor Can Be Engineered to Confer Partial Resistance to the Oomycete Phytophthora infestans in Addition to the Fungus Fusarium oxysporum.

    PubMed

    Giannakopoulou, Artemis; Steele, John F C; Segretin, Maria Eugenia; Bozkurt, Tolga O; Zhou, Ji; Robatzek, Silke; Banfield, Mark J; Pais, Marina; Kamoun, Sophien

    2015-12-01

    Plants and animals rely on immune receptors, known as nucleotide-binding domain and leucine-rich repeat (NLR)-containing proteins, to defend against invading pathogens and activate immune responses. How NLR receptors respond to pathogens is inadequately understood. We previously reported single-residue mutations that expand the response of the potato immune receptor R3a to AVR3a(EM), a stealthy effector from the late blight oomycete pathogen Phytophthora infestans. I2, another NLR that mediates resistance to the will-causing fungus Fusarium oxysporum f. sp. lycopersici, is the tomato ortholog of R3a. We transferred previously identified R3a mutations to I2 to assess the degree to which the resulting I2 mutants have an altered response. We discovered that wild-type I2 protein responds weakly to AVR3a. One mutant in the N-terminal coiled-coil domain, I2(I141N), appeared sensitized and displayed markedly increased response to AVR3a. Remarkably, I2(I141N) conferred partial resistance to P. infestans. Further, I2(I141N) has an expanded response spectrum to F. oxysporum f. sp. lycopersici effectors compared with the wild-type I2 protein. Our results suggest that synthetic immune receptors can be engineered to confer resistance to phylogenetically divergent pathogens and indicate that knowledge gathered for one NLR could be exploited to improve NLR from other plant species.

  17. Secretome analysis of the mycoparasitic fungus Trichoderma harzianum ALL 42 cultivated in different media supplemented with Fusarium solani cell wall or glucose.

    PubMed

    Ramada, Marcelo Henrique Soller; Steindorff, Andrei Stecca; Bloch, Carlos; Ulhoa, Cirano José

    2016-02-01

    Trichoderma harzianum is a fungus well known for its potential as a biocontrol agent against many fungal phytopathogens. The aim of this study was to characterize the proteins secreted by T. harzianum ALL42 when its spores were inoculated and incubated for 48 h in culture media supplemented with glucose (GLU) or with cell walls from Fusarium solani (FSCW), a phytopathogen that causes severe losses in common bean and soy crops in Brazil, as well as other crop diseases around the world. Trichoderma harzianum was able to grow in Trichoderma Liquid Enzyme Production medium (TLE) and Minimal medium (MM) supplemented with FSCW and in TLE+GLU, but was unable to grow in MM+GLU medium. Protein quantification showed that TLE+FSCW and MM+FSCW had 45- and 30- fold, respectively, higher protein concentration on supernatant when compared to TLE+GLU, and this difference was observable on 2D gel electrophoresis (2DE). A total of 94 out of 105 proteins excised from 2DE maps were identified. The only protein observed in all three conditions was epl1. In the media supplemented with FSCW, different hydrolases such as chitinases, β-1,3-glucanases, glucoamylases, α-1,3-glucanases and proteases were identified, along with other proteins with no known functions in mycoparasitism, such as npp1 and cys. Trichoderma harzianum showed a complex and diverse arsenal of proteins that are secreted in response to the presence of FSCW, with novel proteins not previously described in mycoparasitic-related studies.

  18. The Tomato Wilt Fungus Fusarium oxysporum f. sp. lycopersici shares Common Ancestors with Nonpathogenic F. oxysporum isolated from Wild Tomatoes in the Peruvian Andes

    PubMed Central

    Inami, Keigo; Kashiwa, Takeshi; Kawabe, Masato; Onokubo-Okabe, Akiko; Ishikawa, Nobuko; Pérez, Enrique Rodríguez; Hozumi, Takuo; Caballero, Liliana Aragón; de Baldarrago, Fatima Cáceres; Roco, Mauricio Jiménez; Madadi, Khalid A.; Peever, Tobin L.; Teraoka, Tohru; Kodama, Motoichiro; Arie, Tsutomu

    2014-01-01

    Fusarium oxysporum is an ascomycetous fungus that is well-known as a soilborne plant pathogen. In addition, a large population of nonpathogenic F. oxysporum (NPF) inhabits various environmental niches, including the phytosphere. To obtain an insight into the origin of plant pathogenic F. oxysporum, we focused on the tomato (Solanum lycopersicum) and its pathogenic F. oxysporum f. sp. lycopersici (FOL). We collected F. oxysporum from wild and transition Solanum spp. and modern cultivars of tomato in Chile, Ecuador, Peru, Mexico, Afghanistan, Italy, and Japan, evaluated the fungal isolates for pathogenicity, VCG, mating type, and distribution of SIX genes related to the pathogenicity of FOL, and constructed phylogenies based on ribosomal DNA intergenic spacer sequences. All F. oxysporum isolates sampled were genetically more diverse than FOL. They were not pathogenic to the tomato and did not carry SIX genes. Certain NPF isolates including those from wild Solanum spp. in Peru were grouped in FOL clades, whereas most of the NPF isolates were not. Our results suggested that the population of NPF isolates in FOL clades gave rise to FOL by gaining pathogenicity. PMID:24909710

  19. The CarO rhodopsin of the fungus Fusarium fujikuroi is a light-driven proton pump that retards spore germination.

    PubMed

    García-Martínez, Jorge; Brunk, Michael; Avalos, Javier; Terpitz, Ulrich

    2015-01-15

    Rhodopsins are membrane-embedded photoreceptors found in all major taxonomic kingdoms using retinal as their chromophore. They play well-known functions in different biological systems, but their roles in fungi remain unknown. The filamentous fungus Fusarium fujikuroi contains two putative rhodopsins, CarO and OpsA. The gene carO is light-regulated, and the predicted polypeptide contains all conserved residues required for proton pumping. We aimed to elucidate the expression and cellular location of the fungal rhodopsin CarO, its presumed proton-pumping activity and the possible effect of such function on F. fujikuroi growth. In electrophysiology experiments we confirmed that CarO is a green-light driven proton pump. Visualization of fluorescent CarO-YFP expressed in F. fujikuroi under control of its native promoter revealed higher accumulation in spores (conidia) produced by light-exposed mycelia. Germination analyses of conidia from carO(-) mutant and carO(+) control strains showed a faster development of light-exposed carO(-) germlings. In conclusion, CarO is an active proton pump, abundant in light-formed conidia, whose activity slows down early hyphal development under light. Interestingly, CarO-related rhodopsins are typically found in plant-associated fungi, where green light dominates the phyllosphere. Our data provide the first reliable clue on a possible biological role of a fungal rhodopsin.

  20. Biosynthesis of silver nanoparticles by the fungus Arthroderma fulvum and its antifungal activity against genera of Candida, Aspergillus and Fusarium.

    PubMed

    Xue, Baiji; He, Dan; Gao, Song; Wang, Dongyang; Yokoyama, Koji; Wang, Li

    2016-01-01

    The objective of this study was to find one or more fungal strains that could be utilized to biosynthesize antifungal silver nanoparticles (AgNPs). Using morphological and molecular methods, Arthroderma fulvum was identified as the most effective fungal strain for synthesizing AgNPs. The UV-visible range showed a single peak at 420 nm, which corresponded to the surface plasmon absorbance of AgNPs. X-ray diffraction and transmission electron microscopy demonstrated that the biosynthesized AgNPs were crystalline in nature with an average diameter of 15.5±2.5 nm. Numerous factors could potentially affect the process of biosynthesis, and the main factors are discussed here. Optimization results showed that substrate concentration of 1.5 mM, alkaline pH, reaction temperature of 55°C, and reaction time of 10 hours were the optimum conditions for AgNP biosynthesis. Biosynthesized AgNPs showed considerable activity against the tested fungal strains, including Candida spp., Aspergillus spp., and Fusarium spp., especially Candida spp.

  1. Biosynthesis of silver nanoparticles by the fungus Arthroderma fulvum and its antifungal activity against genera of Candida, Aspergillus and Fusarium

    PubMed Central

    Xue, Baiji; He, Dan; Gao, Song; Wang, Dongyang; Yokoyama, Koji; Wang, Li

    2016-01-01

    The objective of this study was to find one or more fungal strains that could be utilized to biosynthesize antifungal silver nanoparticles (AgNPs). Using morphological and molecular methods, Arthroderma fulvum was identified as the most effective fungal strain for synthesizing AgNPs. The UV–visible range showed a single peak at 420 nm, which corresponded to the surface plasmon absorbance of AgNPs. X-ray diffraction and transmission electron microscopy demonstrated that the biosynthesized AgNPs were crystalline in nature with an average diameter of 15.5±2.5 nm. Numerous factors could potentially affect the process of biosynthesis, and the main factors are discussed here. Optimization results showed that substrate concentration of 1.5 mM, alkaline pH, reaction temperature of 55°C, and reaction time of 10 hours were the optimum conditions for AgNP biosynthesis. Biosynthesized AgNPs showed considerable activity against the tested fungal strains, including Candida spp., Aspergillus spp., and Fusarium spp., especially Candida spp. PMID:27217752

  2. Antifungal efficiency of a lipopeptide biosurfactant derived from Bacillus subtilis SPB1 versus the phytopathogenic fungus, Fusarium solani.

    PubMed

    Mnif, Ines; Hammami, Ines; Triki, Mohamed Ali; Azabou, Manel Cheffi; Ellouze-Chaabouni, Semia; Ghribi, Dhouha

    2015-11-01

    Bacillus subtilis SPB1 lipopeptides were evaluated as a natural antifungal agent against Fusarium solani infestation. In vitro antifungal assay showed a minimal inhibitory concentration of about 3 mg/ml with a fungicidal mode of action. In fact, treatment of F. solani by SPB1 lipopeptides generated excessive lyses of the mycelium and caused polynucleation and destruction of the related spores together with a total inhibition of spore production. Furthermore, an inhibition of germination potency accompanied with a high spore blowing was observed. Moreover, in order to be applied in agricultural field, in vivo antifungal activity was proved against the dry rot potato tubers caused by F. solani. Preventive treatment appeared as the most promising as after 20 days of fungi inoculation, rot invasion was reduced by almost 78%, in comparison to that of non-treated one. When treating infected tomato plants, disease symptoms were reduced by almost 100% when applying the curative method. Results of this study are very promising as it enables the use of the crude lipopeptide preparation of B. subtilis SPB1 as a potent natural fungicide that could effectively control the infection of F. solani in tomato and potato tubers at a concentration similar to the commercial fungicide hymexazol and therefore prevent the damage of olive tree.

  3. Thousand cankers disease complex: a forest health issue across the U.S.

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Thousand Cankers Disease (TCD) is a disease complex wherein the fungus (Geosmithia morbida), is vectored by the walnut twig beetle (WTB, Pityophthorus juglandis). Disease causes mortality primarily of eastern black walnut (Juglans nigra), though other walnut species are also susceptible. Eastern bla...

  4. Fusarium wilt of lentil

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Fusarium wilt of lentil is caused by the soil borne fungus Fusaium oxysporum f. sp. lentis. The pathogen is widespread. The disease shows symptoms of wilting, and stunted plants. Other symptoms include wilting of top leaves resemble water deficiency, shrinking and curling of leaves from the lower...

  5. Widespread Distribution of Fungivorus Aphelenchoides spp. in Blight Cankers on American Chestnut Trees.

    PubMed

    Griffin, G J; Eisenback, J D; Oldham, K

    2012-12-01

    Previously we showed in laboratory studies that the fungivorus nematode, Aphelenchoides hylurgi, was attracted to and fed upon the chestnut blight fungus, Cryphonectria parasitica, from American chestnut bark cankers and was a carrier of biocontrol, white hypovirulent C. parasitica strains. In the present field study, we recovered Aphelenchoides spp. in almost all (97.0 %) of 133 blight canker tissue assays (three 5-g samples each) from four eastern states. High mean population densities (227 to 474 nematodes per 5 g tissue) of Aphelenchoides spp. were recovered from cankers in Virginia, West Virginia, and Tennessee but not from New Hampshire (mean = 75 nematodes per 5 g tissue). Overall, most canker assays yielded population densities less than 200 nematodes per 5 g tissue. All of 12 very small or young cankers yielded a few to many Aphelenchoides spp. Regression analysis indicated greatest recovery of Aphelenchoides spp. occurred in the month of May (r = 0.94). The results indicate that Aphelenchoides spp. appear to be widespread in blight cankers on American chestnut trees and could play a role in biocontrol of chestnut blight.

  6. Integrated Management of Citrus Canker

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Fruit losses due to citrus canker, caused by Xanthomonas citri subsp. citri (Xcc), vary each crop season depending on citrus variety, tree age, flushing condition, leafminer control, and coincidence of weather events with occurrence of susceptible fruit and foliage. In 2012, crop losses in Hamlin f...

  7. Draft Genome Sequence of Rhizobium sp. Strain TBD182, an Antagonist of the Plant-Pathogenic Fungus Fusarium oxysporum, Isolated from a Novel Hydroponics System Using Organic Fertilizer.

    PubMed

    Iida, Yuichiro; Fujiwara, Kazuki; Someya, Nobutaka; Shinohara, Makoto

    2017-03-16

    Rhizobium sp. strain TBD182, isolated from a novel hydroponics system, is an antagonistic bacterium that inhibits the mycelial growth of Fusarium oxysporum but does not eliminate the pathogen. We report the draft genome sequence of TBD182, which may contribute to elucidation of the molecular mechanisms of its fungistatic activity.

  8. TaFROG encodes a Pooideae orphan protein that interacts with SnRK1 and enhances resistance to the mycotoxigenic fungus fusarium graminearum.

    Technology Transfer Automated Retrieval System (TEKTRAN)

    All genomes encode taxonomically restricted ‘orphan’ genes, most of which are of unknown function. We report the functional characterization of the orphan gene TaFROG as a component of the wheat resistance to the globally important Fusarium head blight (FHB) disease. TaFROG is taxonomically restrict...

  9. Draft Genome Sequence of Rhizobium sp. Strain TBD182, an Antagonist of the Plant-Pathogenic Fungus Fusarium oxysporum, Isolated from a Novel Hydroponics System Using Organic Fertilizer

    PubMed Central

    Fujiwara, Kazuki; Someya, Nobutaka; Shinohara, Makoto

    2017-01-01

    ABSTRACT Rhizobium sp. strain TBD182, isolated from a novel hydroponics system, is an antagonistic bacterium that inhibits the mycelial growth of Fusarium oxysporum but does not eliminate the pathogen. We report the draft genome sequence of TBD182, which may contribute to elucidation of the molecular mechanisms of its fungistatic activity. PMID:28302768

  10. An Asian ambrosia beetle Euwallacea fornicatus and its novel symbiotic fungus Fusarium sp. pose a serious threat to the Israeli avocado industry

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The ambrosia beetle Euwallacea fornicatus Einchoff was first recorded in Israel in 2009. A novel unnamed symbiotic species within Clade 3 of the Fusarium solani species complex, carried in the mandibular mycangia of the beetle, is responsible for the typical wilt symptoms inflicted on avocado (Perse...

  11. Genetic structure of soil population of fungus Fusarium oxysporum Schlechtend.: Fr.: Molecular reidentification of the species and genetic differentiation of isolates using polymerase chain reaction technique with universal primers (UP-PCR)

    SciTech Connect

    Bulat, S.A.; Mironenko, N.V.; Zholkevich, Yu.G.

    1995-07-01

    The genetic structure of three soil populations of fungus Fusarium oxysporum was analyzed using polymerase chain reaction with universal primers (UP-PCR). Distinct UP-PCR variants revealed by means of cross-dot hybridization of amplified DNA and restriction analysis of nuclear ribosomal DNA represent subspecies or sibling species of F. oxysporum. The remaining isolates of F. oxysporum showed moderate UP-PCR polymorphism characterized by numerous types, whose relatedness was analyzed by computer treatment of the UP-PCR patterns. The genetic distance trees based on the UP-PCR patterns, which were obtained with different universal primers, demonstrated similar topology. This suggests that evolutionarily important genome rearrangements correlatively occur within the entire genome. Isolates representing different UP-PCR polymorphisms were encountered in all populations, being distributed asymmetrically in two of these. In general, soil populations of F. oxysporum were represented by numerous genetically isolated groups with a similar genome structure. The genetic heterogeneity of the isolates within these groups is likely to be caused by the parasexual process. The usefulness of the UP-PCR technique for population studies of F. oxysporum was demonstrated. 39 refs., 7 figs., 2 tabs.

  12. Immobilization of Fusarium verticillioides fungus on nano-silica (NSi-Fus): a novel and efficient biosorbent for water treatment and solid phase extraction of Mg(II) and Ca(II).

    PubMed

    Mahmoud, Mohamed E; Yakout, Amr A; Abdel-Aal, Hany; Osman, Maher M

    2013-04-01

    Biosorption and water treatment of Mg(II) and Ca(II) hardness was designed via surface loading of heat inactivated Fusarium verticillioides fungus (Fus) on nano-silica (NSi) for developing the (NSi-Fus) as a novel biosorbent. Surface characterization was confirmed by FT-IR and SEM analysis. The (NSi), (Fus) and (NSi-Fus) sorbents were investigated for removal of Mg(II) and Ca(II) by using the batch equilibrium technique under the influence of solution pH, contact time, sorbent dosage, initial metal concentration and interfering ion. The maximum magnesium capacity values were identified as 600.0, 933.3 and 1000.0 μmole g(-1) while, the maximum calcium values were 1066.7, 1800.0 and 1333.3 μmole g(-1) for (NSi), (Fus) and (NSi-Fus), respectively. Sorption equilibria were established in ∼20 min and the data were well described by both Langmuir and Freundlich models. The potential applications of these biosorbents for water-softening and extraction of magnesium and calcium from sea water samples were successfully accomplished.

  13. Biotransformation of ent-kaur-16-ene and ent-trachylobane 7β-acetoxy derivatives by the fungus Gibberella fujikuroi (Fusarium fujikuroi).

    PubMed

    Fraga, Braulio M; Bressa, Carlo; González-Vallejo, Victoria; González, Pedro; Guillermo, Ricardo

    2012-09-01

    Candol A (7β-hydroxy-ent-kaur-16-ene) (6) is efficiently transformed by Gibberella fujikuroi into the gibberellin plant hormones. In this work, the biotransformation of its acetate by this fungus has led to the formation of 7β-acetoxy-ent-kaur-16-en-19-oic acid (3), whose corresponding alcohol is a short-lived intermediate in the biosynthesis of gibberellins and seco-ring ent-kaurenoids in this fungus. Further biotransformation of this compound led to the hydroxylation of the 3β-positions to give 7β-acetoxy-3β-hydroxy-ent-kaur-16-en-19-oic acid (14), followed by a 2β- or 18-hydroxylation of this metabolite. The incubation of epicandicandiol 7β-monoacetate (7β-acetoxy-18-hydroxy-ent-kaur-16-ene) (10) produces also the 19-hydroxylation to form the 18,19 diol (20), which is oxidized to give the corresponding C-18 or C-19 acids. These results indicated that the presence of a 7β-acetoxy group does not inhibit the fungal oxidation of C-19 in 7β-acetoxy-ent-kaur-16-ene, but avoids the ring B contraction that leads to the gibberellins and the 6β-hydroxylation necessary for the formation of seco-ring B ent-kaurenoids. The biotransformation of 7β-acetoxy-ent-trachylobane (trachinol acetate) (27) only led to the formation of 7β-acetoxy-18-hydroxy-ent-trachylobane (33).

  14. Involvement of the salicylic acid signaling pathway in the systemic resistance induced in Arabidopsis by plant growth-promoting fungus Fusarium equiseti GF19-1.

    PubMed

    Kojima, Hanae; Hossain, Md Motaher; Kubota, Mayumi; Hyakumachi, Mitsuro

    2013-01-01

    Plant growth-promoting fungi (PGPF) are effective biocontrol agents for a number of soil-borne diseases and are known for their ability to trigger induced systemic resistance (ISR). In this study, we investigated the mechanisms triggered by PGPF Fusarium equiseti GF19-1, which is known to increase pathogen resistance in plants, by using GF19-1 spores and the culture filtrate (CF) to treat the roots of Arabidopsis thaliana. Subsequently, the leaves were challenged with Pseudomonas syringae pv tomato DC3000 (Pst) bacteria. Arabidopsis plants treated with GF19-1 spores or the CF elicited ISR against the Pst pathogen, resulting in a restriction of disease severity and suppression of pathogen proliferation. Examination of ISR in various signaling mutants and transgenic plants showed that GF19-1-induced protection was observed in the jasmonate response mutant jar1 and the ethylene response mutant etr1, whereas it was blocked in Arabidopsis plants expressing the NahG transgene or demonstrating a disruption of the NPR1 gene (npr1). Analysis of systemic gene expression revealed that GF19-1 modulates the expression of salicylic acid (SA)-responsive PR-1, PR-2, and PR-5 genes. Moreover, transient accumulation of SA was observed in GF19-1-treated plant, whereas the level was further enhanced after Pst infection of GF19-1-pretreated plants, indicating that accumulation of SA was potentiated when Arabidopsis plants were primed for disease resistance by GF19-1. In conclusion, these findings imply that the induced protective effect conferred by F. equiseti GF19-1 against the leaf pathogen Pst requires responsiveness to an SA-dependent pathway.

  15. Reasons for inconsistent citrus canker control

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Crop losses from citrus canker in 2014 for Hamlin due to premature fruit drop, or for grapefruit from unacceptable severity of fruit lesions, were highly variable due to periodic rains that in certain locations were coincident with grapefruit flushes in February-March or with early Hamlin fruit deve...

  16. Research progress for integrated canker management

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Fruit losses due to citrus canker, caused by Xanthomonas citri subsp. citri (Xcc), vary each crop season depending on citrus variety, tree age, flushing condition, leafminer control, and coincidence of weather events with occurrence of susceptible fruit and foliage. In 2013, crop losses in Hamlin f...

  17. Gnomoniopsis smithogilvyi causes chestnut canker symptoms in Castanea sativa shoots in Switzerland.

    PubMed

    Pasche, Sabrina; Calmin, Gautier; Auderset, Guy; Crovadore, Julien; Pelleteret, Pegah; Mauch-Mani, Brigitte; Barja, François; Paul, Bernard; Jermini, Mauro; Lefort, François

    2016-02-01

    A screening of Castanea sativa scions for grafting for the presence of endophytes showed that the opportunistic fungal pathogen Gnomoniopsis smithogilvyi was the most abundant member of the endophytic flora. This fungus is known as a pathogen affecting chestnut fruits in Italy and Australia. Here, we present evidence that it causes cankers very similar to the ones due to Cryphonectria parasitica infection on twigs and scions of chestnut trees. We found natural infections of G. smithogilvyi in healthy grafted plants as well as in scions from chestnut trees. The identity of the fungus isolated from asymptomatic tissues was verified by applying Koch's postulates and corroborated by DNA sequencing of four different gene regions. In contrast to C. parasitica that appears on the bark as yellow to orange pycnidia, stromata and slimy twisted tendrils, G. smithogilvyi forms orange to red and black pycnidia, gray stromata and cream-colored to beige slimy twisted tendrils on the bark. These Swiss strains are closely related to G. smithogilvyi strains from Australia and from New Zealand, Gnomoniopsis sp. and Gnomoniopsis castanea from New Zealand, Italy, France and Switzerland. While the strains from Ticino are genetically very close to G. smithogilvyi and G. castanea from Italy, the differences between the strains from Ticino and Geneva suggest two different origins. The present study supports the hypothesis that a single species named G. smithogilvyi, which is known to be the agent of chestnut rot, also causes wood cankers on chestnut.

  18. Fusicoccum arbuti sp. nov. causing cankers on pacific madrone in western North America with notes on Fusicoccum dimidiatum, the correct name for Scytalidium dimidiatum and Nattrassia mangiferae.

    PubMed

    Farr, David F; Elliott, Marianne; Rossman, Amy Y; Edmonds, Robert L

    2005-01-01

    Pacific madrone (Arbutus menziesii) is a broadleaf evergreen tree native to western North America that has been in decline for the past 30 years. A fungus has been isolated and was verified as the cause of cankers on dying trees. It was determined to belong in the genus Fusicoccum, an asexual state of Botryosphaeria. This genus in both its sexual and asexual states commonly causes canker diseases of deciduous woody plants. Using morphological and molecular data the fungus causing cankers on Pacific madrone is characterized, described and illustrated as a new species of Fusicoccum, F. arbuti D.F. Farr & M. Elliott sp. nov. No sexual state is known for F. arbuti. Evidence from the literature, cultures and specimens suggests that F. arbuti, often mistakenly identified as Nattrassia mangiferae, has been causing madrone canker since at least 1968. Authentic isolates of Nattrassia mangiferae as the synanamorph Scytalidium dimidiatum were sequenced and determined to be different from Fusicoccum arbuti and to belong in Botryosphaeria/Fusicoccum. In addition to molecular sequence data, the morphology of the pycnidial and arthric conidial states of Nattrassia mangiferae/ Scytalidium dimidiatum resembles that of Fusicoccum. Therefore the correct name for Nattrassia mangiferae and its numerous synonyms (Dothiorella mangiferae, Torula dimidata, Scytilidium dimidiatum, Fusicoccum eucalypti, Hendersonula toruloidea, H. cypria, Exosporina fawcetii, H. agathidia, and S. lignicola) is Fusicoccum dimidiatum (Penz.) D.F. Farr, comb. nov.

  19. Apple anthracnose canker life cycle and disease cycle

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Apple anthracnose [caused by Neofabraea malicorticis (H.S. Jacks) anamorph Cryptosporiopsis curvispora (Peck)] is a fungal disease that impacts apple production. The pathogen produces cankers on trees as well as a rot on the fruit known as ‘Bull’s-eye rot’. The cankers cause severe damage to trees...

  20. Research promises earlier warning for grapevine canker diseases

    Technology Transfer Automated Retrieval System (TEKTRAN)

    When it comes to detecting and treating vineyards for grapevine canker diseases (also called trunk diseases), like Botryosphaeria dieback (Bot canker), Esca, Eutypa dieback and Phomopsis dieback, the earlier the better, says plant pathologist Kendra Baumgartner, with the USDA’s Agricultural Research...

  1. Family disintegration: one fusarium verticillioides beta-lactamase at a time

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Fusarium verticillioides is a mycotoxigenic fungus found commonly on maize, where it primarily exhibits asymptomatic endophytic growth. The F. verticillioides genome possesses approximately 30 regions that potentially encode beta-lactamase enzymatic domains. These enzymes are classically involved ...

  2. Population genomics of Fusarium graminearum head blight pathogens in North America

    Technology Transfer Automated Retrieval System (TEKTRAN)

    In this study we utilized comparative genomics to identify candidate adaptive alleles in the fungus Fusarium graminearum, the primary pathogen of Fusarium head blight (FHB) in cereal crops. Recent epidemics of FHB have been economically devastating to agriculture, as F. graminearum reduces cereal yi...

  3. Insights into natural products biosynthesis from analysis of 490 polyketide synthases from Fusarium

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Species of the fungus Fusarium collectively cause disease on almost all crop plants and produce numerous natural products (NPs), including some of the mycotoxins of greatest concern to agriculture. Many Fusarium NPs are derived from polyketide synthases, large multi-domain enzymes that catalyze sequ...

  4. New tricks of an old enemy: isolates of Fusarium graminearum produce a type A trichothecene mycotoxin

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The ubiquitous filamentous fungus Fusarium graminearum causes the important disease Fusarium head blight on various species of cereals, leading to contamination of grains with mycotoxins. In a survey of F. graminearum (sensu stricto) on wheat in North America several novel strains were isolated, whi...

  5. Genetic transformation of Fusarium oxysporum f.sp. gladioli with Agrobacterium to study pathogenesis in Gladiolus

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Fusarium rot caused by Fusarium oxysporum f.sp. gladioli (Fog) is one of the most serious diseases of Gladiolus, both in the field and in stored bulbs. In order to study the pathogenesis of this fungus, we have transformed Fog with Agrobacterium tumefaciens binary vectors containing the hygromycin B...

  6. New tricks of an old enemy: Isolates of Fusarium graminearum produce a type A trichothecene mycotoxin

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The ubiquitous filamentous fungus Fusarium graminearum causes the important disease Fusarium head blight on various species of cereals, leading to contamination of grains with mycotoxins. In a survey of F. graminearum (sensu stricto) on wheat in North America several novel strains were isolated, whi...

  7. A major quantitative trait locus is associated with Fusarium Wilt Race 1 resistance in watermelon

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Fusarium wilt is a major disease of watermelon caused by the soil-borne fungus Fusarium oxysporum Schlechtend.:Fr. f. sp. niveum (E.F. Sm.) W.C. Snyder & H.N. Hans (Fon). A genetic population of 186 F3 families (24 plants in each family) exhibited continuous segregation for Fon race 1 response. Geno...

  8. Diallel analysis of resistance to fusarium ear rot and fumonisin contamination in maize

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The fungus Fusarium verticillioides infects maize ears and kernels, resulting in Fusarium ear rot disease, reduced grain yields, and contamination of grain with the mycotoxin fumonisin. Typical hybrid maize breeding programs involve selection for both favorable inbred and hybrid performance, and the...

  9. First Report on Fusarium Wilt of Zucchini Caused by Fusarium oxysporum, in Korea.

    PubMed

    Choi, In-Young; Kim, Ju-Hee; Lee, Wang-Hyu; Park, Ji-Hyun; Shin, Hyeon-Dong

    2015-06-01

    Fusarium wilt of zucchini in Jeonju, Korea, was first noticed in May 2013. Symptoms included wilting of the foliage, drying and withering of older leaves, and stunting of plants. Infected plants eventually died during growth. Based on morphological characteristics and phylogenetic analyses of the molecular markers (internal transcribed spacer rDNA and translation elongation factor 1α), the fungus was identified as Fusarium oxysporum. Pathogenicity of a representative isolate was demonstrated via artificial inoculation, and it satisfied Koch's postulates. To our knowledge, this is the first report of F. oxysporum causing wilt of zucchini in Korea.

  10. Labelling studies on the biosynthesis of terpenes in Fusarium fujikuroi.

    PubMed

    Citron, Christian A; Brock, Nelson L; Tudzynski, Bettina; Dickschat, Jeroen S

    2014-05-25

    Synthetic [2-(13)C]mevalonolactone was fed to the gibberellin producer Fusarium fujikuroi and its incorporation into four known terpenoids was investigated by (13)C NMR analysis of crude culture extracts. The experiments gave detailed insights into the mechanisms of terpene biosynthesis by this fungus.

  11. The depudecin cluster – a genetic curiosity in Fusarium langsethiae

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Fusarium langsethiae is a consistent fungal contaminant on oat cereals in the Nordic region, the UK, as well as other parts of Europe. Leaving few symptoms of disease on the plant, the fungus is, however, the main producer of T-2 and HT-2 mycotoxins which can be found contaminating food and feed der...

  12. Effector profiles distinguish formae speciales of Fusarium oxysporum

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Formae speciales (ff. spp.) of the fungus Fusarium oxysporum are often polyphyletic in their origin, meaning that strains that infect a particular plant species are not necessarily more closely related to each other than to strains that cause disease in another host. Nevertheless, since strains of t...

  13. Lignin Degradation by Fusarium solani f. sp. glycines

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Sudden death syndrome (SDS), caused by the soilborne fungal pathogen Fusarium solani f. sp. glycines, is one of the most important diseases of soybean. Lignin degradation may play a role in the infection, colonization, and survival of the fungus in root tissue . Lignin degradation by F. solani f. sp...

  14. Molecular Exploration of Beta-Lactamases in Fusarium verticillioides

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The mycotoxigenic fungus Fusarium verticillioides (Fv) is one of the most prevalent maize fungal pathogens. Fv mycotoxins are a significant food safety issue and have given rise to exposure concerns worldwide. The FDB1 locus, a beta-lactamase-containing Fv gene cluster, was previously shown to be in...

  15. Fusarium MLST database

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The CBS-KNAW Fungal Biodiversity Centre’s Fusarium MLST website (http://www.cbs.knaw.nl/Fusarium), and the corresponding Fusarium-ID site hosted at the Pennsylvania State University (http://isolate.fusariumdb.org; Geiser et al. 2004, Park et al. 2010) were constructed to facilitate identification of...

  16. Incorporating exposure to pitch canker disease to support management decisions of Pinus pinaster Ait. in the face of climate change.

    PubMed

    Serra-Varela, María Jesús; Alía, Ricardo; Pórtoles, Javier; Gonzalo, Julián; Soliño, Mario; Grivet, Delphine; Raposo, Rosa

    2017-01-01

    Climate change is gravely affecting forest ecosystems, resulting in large distribution shifts as well as in increasing infection diseases and biological invasions. Accordingly, forest management requires an evaluation of exposure to climate change that should integrate both its abiotic and biotic components. Here we address the implications of climate change in an emerging disease by analysing both the host species (Pinus pinaster, Maritime pine) and the pathogen's (Fusarium circinatum, pitch canker) environmental suitability i.e. estimating the host's risk of habitat loss and the disease`s future environmental range. We constrained our study area to the Spanish Iberian Peninsula, where accurate climate and pitch canker occurrence databases were available. While P. pinaster is widely distributed across the study area, the disease has only been detected in its north-central and north-western edges. We fitted species distribution models for the current distribution of the conifer and the disease. Then, these models were projected into nine Global Climate Models and two different climatic scenarios which totalled to 18 different future climate predictions representative of 2050. Based on the level of agreement among them, we created future suitability maps for the pine and for the disease independently, which were then used to assess exposure of current populations of P. pinaster to abiotic and biotic effects of climate change. Almost the entire distribution of P. pinaster in the Spanish Iberian Peninsula will be subjected to abiotic exposure likely to be driven by the predicted increase in drought events in the future. Furthermore, we detected a reduction in exposure to pitch canker that will be concentrated along the north-western edge of the study area. Setting up breeding programs is recommended in highly exposed and productive populations, while silvicultural methods and monitoring should be applied in those less productive, but still exposed, populations.

  17. Incorporating exposure to pitch canker disease to support management decisions of Pinus pinaster Ait. in the face of climate change

    PubMed Central

    Serra-Varela, María Jesús; Alía, Ricardo; Pórtoles, Javier; Gonzalo, Julián; Soliño, Mario; Grivet, Delphine; Raposo, Rosa

    2017-01-01

    Climate change is gravely affecting forest ecosystems, resulting in large distribution shifts as well as in increasing infection diseases and biological invasions. Accordingly, forest management requires an evaluation of exposure to climate change that should integrate both its abiotic and biotic components. Here we address the implications of climate change in an emerging disease by analysing both the host species (Pinus pinaster, Maritime pine) and the pathogen’s (Fusarium circinatum, pitch canker) environmental suitability i.e. estimating the host’s risk of habitat loss and the disease`s future environmental range. We constrained our study area to the Spanish Iberian Peninsula, where accurate climate and pitch canker occurrence databases were available. While P. pinaster is widely distributed across the study area, the disease has only been detected in its north-central and north-western edges. We fitted species distribution models for the current distribution of the conifer and the disease. Then, these models were projected into nine Global Climate Models and two different climatic scenarios which totalled to 18 different future climate predictions representative of 2050. Based on the level of agreement among them, we created future suitability maps for the pine and for the disease independently, which were then used to assess exposure of current populations of P. pinaster to abiotic and biotic effects of climate change. Almost the entire distribution of P. pinaster in the Spanish Iberian Peninsula will be subjected to abiotic exposure likely to be driven by the predicted increase in drought events in the future. Furthermore, we detected a reduction in exposure to pitch canker that will be concentrated along the north-western edge of the study area. Setting up breeding programs is recommended in highly exposed and productive populations, while silvicultural methods and monitoring should be applied in those less productive, but still exposed, populations

  18. Analyses of the Xylem Sap Proteomes Identified Candidate Fusarium virguliforme Proteinacious Toxins

    PubMed Central

    Abeysekara, Nilwala S.; Bhattacharyya, Madan K.

    2014-01-01

    Background Sudden death syndrome (SDS) caused by the ascomycete fungus, Fusarium virguliforme, exhibits root necrosis and leaf scorch or foliar SDS. The pathogen has never been identified from the above ground diseased foliar tissues. Foliar SDS is believed to be caused by host selective toxins, including FvTox1, secreted by the fungus. This study investigated if the xylem sap of F. virguliforme-infected soybean plants contains secreted F. virguliforme-proteins, some of which could cause foliar SDS development. Results Xylem sap samples were collected from five biological replications of F. virguliforme-infected and uninfected soybean plants under controlled conditions. We identified five F. virguliforme proteins from the xylem sap of the F. virguliforme-infected soybean plants by conducting LC-ESI-MS/MS analysis. These five proteins were also present in the excreted proteome of the pathogen in culture filtrates. One of these proteins showed high sequence identity to cerato-platanin, a phytotoxin produced by Ceratocystis fimbriata f. sp. platani to cause canker stain disease in the plane tree. Of over 500 soybean proteins identified in this study, 112 were present in at least 80% of the sap samples collected from F. virguliforme-infected and -uninfected control plants. We have identified four soybean defense proteins from the xylem sap of F. virguliforme-infected soybean plants. The data have been deposited to the ProteomeXchange with identifier PXD000873. Conclusion This study confirms that a few F. virguliforme proteins travel through the xylem, some of which could be involved in foliar SDS development. We have identified five candidate proteinaceous toxins, one of which showed high similarity to a previously characterized phytotoxin. We have also shown the presence of four soybean defense proteins in the xylem sap of F. virguliforme-infected soybean plants. This study laid the foundation for studying the molecular basis of foliar SDS development in soybean and

  19. Inhibition of Fusarium graminiarum growth in flour gel cultures by hexane soluble compounds from oat (Avena sativa L.) flour

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Fusarium head blight, caused by the fungus Fusarium graminearum, primarily affects wheat (Triticum aestivum) and barley (Hordeum vulgarum) while oat (Avena sativa) appears to be more resistant. Although this has generally been attributed to the open panicle of oats, we hypothesized that a chemical c...

  20. Quantification of Fusarium virguliforme in soybean roots of partially resistant and susceptible genotypes using quantitative polymerase chain reaction

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Soybean sudden death syndrome, caused by Fusarium virguliforme (syn. Fusarium solani f. sp. glycines), was first reported in 1971, in Arkansas. Since then, the fungus has spread to the northern United States, causing significant soybean yield losses. Soybean resistance to F. virguliforme is consider...

  1. Copper Sprays and Windbreaks for Control of Citrus Canker on Young Orange Trees in Southern Brazil

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The benefit of windbreaks and copper sprays for control of citrus canker caused by Xanthomonas axonopodis pv. citri was investigated in a commercial citrus orchard located in a citrus canker endemic area in southern Brazil. Control of canker was evaluated as incidence and severity of lesions on foli...

  2. Horsfall-Barratt recalibration and replicated severity estimates of citrus canker

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Citrus canker is a serious disease of citrus in tropical and subtropical citrus growing regions. Accurate and precise assessment of citrus canker and other plant pathogens is needed to obtain good quality data. Citrus canker assessment data were used to ascertain some of the mechanics of the Horsfal...

  3. Ethanol attracts scolytid beetles to Phytophthora ramorum cankers on coast live oak

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Technical abstract: Ethanol in sapwood was analyzed along vertical transects, through small spot cankers and larger basal cankers, of Phytophthora ramorum-infected stems of Quercus agrifolia at three sites in California. Trees with large basal cankers, known to attract scolytid beetles, had a 4.3 ti...

  4. Novel taxa in the Fusarium fujikuroi species complex from Pinus spp.

    PubMed Central

    Herron, D.A.; Wingfield, M.J.; Wingfield, B.D.; Rodas, C.A.; Marincowitz, S.; Steenkamp, E.T.

    2015-01-01

    The pitch canker pathogen Fusarium circinatum has caused devastation to Pinus spp. in natural forests and non-natives in commercially managed plantations. This has drawn attention to the potential importance of Fusarium species as pathogens of forest trees. In this study, we explored the diversity of Fusarium species associated with diseased Pinus patula, P. tecunumanii, P. kesiya and P. maximinoi in Colombian plantations and nurseries. Plants displaying symptoms associated with a F. circinatum-like infection (i.e., stem cankers and branch die-back on trees in plantations and root or collar rot of seedlings) were sampled. A total of 57 isolates were collected and characterised based on DNA sequence data for the translation elongation factor 1-α and β-tubulin gene regions. Phylogenetic analyses of these data allowed for the identification of more than 10 Fusarium species. These included F. circinatum, F. oxysporum, species within the Fusarium solani species complex and seven novel species in the Fusarium fujikuroi species complex (formerly the Gibberella fujikuroi species complex), five of which are described here as new. Selected isolates of the new species were tested for their pathogenicity on Pinus patula and compared with that of F. circinatum. Of these, F. marasasianum, F. parvisorum and F. sororula displayed levels of pathogenicity to P. patula that were comparable with that of F. circinatum. These apparently emerging pathogens thus pose a significant risk to forestry in Colombia and other parts of the world. PMID:26955193

  5. The transcription cofactor FgSwi6 plays a role in growth and development, carbendazim sensitivity, cellulose utilization, lithium tolerance, deoxynivalenol production and virulence in the filamentous fungus Fusarium graminearum.

    PubMed

    Liu, Ningning; Fan, Feiyu; Qiu, Dewen; Jiang, Linghuo

    2013-01-01

    Fusarium head blight (FHB) is a worldwide devastating disease of wheat, barley and other small grain cereals and caused primarily by Fusarium graminearum. Carbendazim (MBC) is one of the fungicides widely used to control FHB in China. In the present study, we have identified the F. graminearum locus FGSG_04220 as the sequence homolog for Saccharomyces cerevisiae ScSWI6, named FgSWI6 hereafter. Deletion of FgSWI6 causes mycelium of F. graminearum become sensitive to MBC in liquid medium. In addition, deletion of FgSWI6 reduces mycelial growth as well as production and development of conidia. F. graminearum cells lacking FgSWI6 show reduced production efficiency and sizes of perithecia as well as a defect in the production of ascus and ascospore. FgSWI6 is required for the cellulose utilization, lithium tolerance and deoxynivalenol (DON) production of this pathogen. Furthermore, deletion of FgSWI6 significantly attenuates the virulence of F. graminearum on wheat. Therefore, FgSwi6p plays an important role in growth and development of the economically important fungal pathogen F. graminearum as well as its resistance to MBC.

  6. Inhibition of HMG-CoA reductase by MFS, a purified extract from the fermentation of marine fungus Fusarium solani FG319, and optimization of MFS production using response surface methodology.

    PubMed

    Zhou, Yu; Wu, Wen-Hui; Zhao, Qing-Bo; Wang, Xiao-Yu; Bao, Bin

    2015-05-01

    The present study was designed to isolate and characterize a purified extract from Fusarium solani FG319, termed MFS (Metabolite of Fusarium solani FG319) that showed anti-atherosclerosis activity by inhibiting 3-hydroxy-3-methylglutaryl coenzyme A (HMG-CoA) reductase. Response surface methodology (RSM) was employed to achieve an improved yield from the fermentation medium. The inhibiting effect of the isolate, MFS, on HMG-CoA reductase was greater than that of the positive control, lovastatin. The average recovery of MFS and the relative standard deviation (RSD) ranged between 99.75% to 101.18%, and 0.31% to 0.74%, respectively. The RSDs intra- and inter-assay of the three samples ranged from 0.288% to 2.438%, and from 0.934% to 2.383%, respectively. From the RSM, the concentration of inducer, cultivation time, and culture temperatures had significant effects on the MFS production, with the effect of inducer concentration being more pronounced that other factors. In conclusion, the optimal conditions for the MFS production were achieved using RSM and that MFS could be explored as an anti-atherosclerosis agent based on its ability to inhibit HMG-CoA reductase.

  7. Multi-gene phylogenies and phenotypic characters distinguish two species within the Colletogloeopsis zuluensis complex associated with Eucalyptus stem cankers

    PubMed Central

    Cortinas, Maria-Noel; Crous, Pedro W.; Wingfield, Brenda D.; Wingfield, Michael J.

    2006-01-01

    Colletogloeopsis zuluensis, previously known as Coniothyrium zuluense, causes a serious stem canker disease on Eucalyptus spp. grown as non-natives in many tropical and sub-tropical countries. This stem canker disease was first reported from South Africa and it has subsequently been found on various species and hybrids of Eucalyptus in other African countries as well as in countries of South America and South-East Asia. In previous studies, phylogenetic analyses based on DNA sequence data of the ITS region suggested that all material of C. zuluensis was monophyletic. However, the occurrence of the fungus in a greater number of countries, and analyses of DNA sequences with additional isolates has challenged the notion that a single species is involved with Coniothyrium canker. The aim of this study was to consider the phylogenetic relationships amongst C. zuluensis isolates from all available locations and to support these analyses with phenotypic and morphological comparisons. Individual and combined phylogenies were constructed using DNA sequences from the ITS region, exons 3 through 6 of the β-tubulin gene, the intron of the translation elongation factor 1-α gene, and a partial sequence of the mitochondrial ATPase 6 gene. Both phylogenetic data and morphological characteristics showed clearly that isolates of C. zuluensis represent at least two taxa. One of these is C. zuluensis as it was originally described from South Africa, and we provide an epitype for it. The second species occurs in Argentina and Uruguay, and is newly described as C. gauchensis. Both fungi are serious pathogens resulting in identical symptoms. Recognising them as different species has important quarantine consequences. PMID:18490975

  8. A meiotic drive element in the maize pathogen Fusarium verticillioides is located within a 102-kb region of chromosome V

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Fusarium verticillioides is an agriculturally important fungus because of its association with maize and its propensity to contaminate grain with toxic compounds. Some isolates of the fungus harbor a meiotic drive element known as Spore killer (SkK) that causes nearly all surviving meiotic progeny f...

  9. Variation in Host and Pathogen in the Neonectria/Malus Interaction; toward an Understanding of the Genetic Basis of Resistance to European Canker

    PubMed Central

    Gómez-Cortecero, Antonio; Saville, Robert J.; Scheper, Reiny W. A.; Bowen, Joanna K.; Agripino De Medeiros, Hugo; Kingsnorth, Jennifer; Xu, Xiangming; Harrison, Richard J.

    2016-01-01

    Apple canker caused by the phytopathogenic fungus Neonectria ditissima is an economically important disease, which has spread in recent years to almost all pome-producing regions of the world. N. ditissima is able to cross-infect a wide range of apple varieties and causes branch and trunk lesions, known as cankers. Most modern apple varieties are susceptible and in extreme cases suffer from high mortality (up to 50%) in the early phase of orchard establishment. There is no known race structure of the pathogen and the global level of genetic diversity of the pathogen population is unknown. Resistance breeding is underway in many global breeding programmes, but nevertheless, a total resistance to canker has not yet been demonstrated. Here we present preliminary data from a survey of the phylogenetic relationships between global isolates of N. ditissima which reveals only slight evidence for population structure. In addition we report the results of four rapid screening tests to assess the response to N. ditissima in different apple scion and rootstock varieties, which reveals abundant variation in resistance responses in both cultivar and rootstock material. Further seedling tests show that the segregation patterns of resistance and susceptibility vary widely between crosses. We discuss inconsistencies in test performance with field observations and discuss future research opportunities in this area. PMID:27695463

  10. Fungus Amongus

    ERIC Educational Resources Information Center

    Wakeley, Deidra

    2005-01-01

    This role-playing simulation is designed to help teach middle level students about the typical lifecycle of a fungus. In this interactive simulation, students assume the roles of fungi, spores, living and dead organisms, bacteria, and rain. As they move around a playing field collecting food and water chips, they discover how the organisms…

  11. Pruning for prevention and management of canker diseases

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Trunk diseases (wood-canker diseases) threaten all California vineyards due to widespread distribution of the fungal pathogens. The infections are chronic and occur each year. Trunk diseases in mature vineyards reduce yields and increase management costs to the point where the vineyard is no longer ...

  12. 76 FR 81359 - European Larch Canker; Expansion of Regulated Areas

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-12-28

    ... From the Federal Register Online via the Government Publishing Office DEPARTMENT OF AGRICULTURE Animal and Plant Health Inspection Service 7 CFR Part 301 European Larch Canker; Expansion of Regulated Areas AGENCY: Animal and Plant Health Inspection Service, USDA. ACTION: Affirmation of interim rule...

  13. 76 FR 52543 - European Larch Canker; Expansion of Regulated Areas

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-08-23

    ... From the Federal Register Online via the Government Publishing Office DEPARTMENT OF AGRICULTURE Animal and Plant Health Inspection Service 7 CFR Part 301 European Larch Canker; Expansion of Regulated Areas AGENCY: Animal and Plant Health Inspection Service, USDA. ACTION: Interim rule and request...

  14. Citrus diseases with global ramifications including citrus canker and huanglongbing

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Although there are a number of diseases that plague citrus production worldwide, two bacterial diseases are particularly problematic. Both are of Asian origin and currently cause severe economic damage: Asiatic citrus canker (ACC) and citrus huanglongbing (HLB). Although ACC has been found in the ...

  15. Developing Transgenic Citrus for Resistance to Huanglongbing and Citrus Canker

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Huanglongbing (HLB) and Citrus Bacterial Canker (CBC) are serious threats to citrus production, and resistant transgenic citrus is desirable. Genes for antimicrobial peptides (AMPs) with diverse promoters have been used to generate thousands of rootstock and scion transformants. D35S::D4E1 transfor...

  16. Agrobacterium tumefaciens-mediated transformation of the causative agent of Valsa canker of apple tree Valsa mali var. mali.

    PubMed

    Hu, Yang; Dai, Qingqing; Liu, Yangyang; Yang, Zhe; Song, Na; Gao, Xiaoning; Voegele, Ralf Thomas; Kang, Zhensheng; Huang, Lili

    2014-06-01

    Valsa mali var. mali (Vmm), which is the causative agent of Valsa canker of apple tree, causes heavy damage to apple production in eastern Asia. In this article, we report Agrobacterium tumefaciens-mediated transformation (ATMT) of Vmm and expression of gfp (green fluorescent protein) in this fungus. The transformation system was optimized to a transformation efficiency of approximately 150 transformants/10(6) conidia, and a library containing over 4,000 transformants was generated. The tested transformants were mitotically stable. One hundred percent hph (hygromycin B phosphotransferase) integration into Vmm was identified by PCR and five single-copy integration of T-DNA was detected in the eighteen transformants by Southern blot. To our knowledge, this is the first report of ATMT of Vmm. Furthermore, this library has been used to identify genes involved in the virulence of the pathogen, and the transformation system may also be useful to the transformation of other species of the genus Valsa.

  17. Fusarium Wilt of Orchids

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Fusarium wilt of orchids is highly destructive and economically limiting to the production of quality orchids that has steadily increased in many production facilities. Important crops such as phalaenopsis, cattleyas, and oncidiums appear to be especially susceptible to certain Fusarium species. Fu...

  18. Disruption of ceramide biosynthesis and accumulation of sphingoid bases and sphingoid base 1-phosphates: A mechanism for Fusarium verticillioides effects in maize-seedling disease.

    Technology Transfer Automated Retrieval System (TEKTRAN)

    In sweet corn at the seedling and seed maturation stages, Fusarium can be a serious field problem. The fungus Fusarium verticillioides infects maize and produces fumonisins, inhibitors of ceramide synthase. To determine the role of fumonisins in maize seedling disease, seeds were inoculated with fu...

  19. Dynamic regions within and horizontal transfer of an otherwise stable gene cluster responsible for synthesis of the Fusarium mycotoxin fusaric acid

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The Fusarium mycotoxin fusaric acid is toxic to plants as well as animals, but its function in the biology of the fungus is not known. Here, we used genome sequencing to survey multiple species in 18 lineages (species complexes) of Fusarium for the presence of the fusaric acid biosynthetic gene (FUB...

  20. Diagnosis of Fusarium keratitis in an animal model using the polymerase chain reaction

    PubMed Central

    Alexandrakis, G.; Jalali, S.; Gloor, P.

    1998-01-01

    AIMS/BACKGROUND—The purpose of this study was apply the polymerase chain reaction (PCR) to develop a sensitive, specific, and rapid test to diagnose Fusarium keratitis. Fusarium is the most common cause of fungal corneal infection in some parts of the world. It is often difficult to establish that a keratitis is due to fungal infection.
METHODS—Fusarium solani keratitis was induced in three eyes of three rabbits by injection of a suspension of the fungus into the anterior corneal stroma. In one rabbit the contralateral eye served as a control. From four to 28 days after inoculation, the corneas were scraped for culture, then scraped and swabbed for PCR analysis. The PCR was performed with primers directed against a portion of the Fusarium cutinase gene, and the presence or absence of this amplified target sequence was determined by agarose gel.
RESULTS—The amplified DNA sequence was detected in 25 of 28 samples from the corneas infected with Fusarium, for a sensitivity of 89%. Only three of the 14 samples from these eyes with Fusarium keratitis were positive by culture, for a sensitivity of 21%. Seven of eight control samples were negative by the PCR based test, for a specificity of 88%.
CONCLUSION—This PCR based test holds promise of being an effective method of diagnosing Fusarium keratitis as well as Fusarium infections at other sites.

 Keywords: keratitis; Fusarium; ulcer; cornea; polymerase chain reaction PMID:9602631

  1. Evaluation of two methods for direct detection of Fusarium spp. in water.

    PubMed

    Graça, Mariana G; van der Heijden, Inneke M; Perdigão, Lauro; Taira, Cleison; Costa, Silvia F; Levin, Anna S

    2016-04-01

    Fusarium is a waterborne fungus that causes severe infections especially in patients with prolonged neutropenia. Traditionally, the detection of Fusarium in water is done by culturing which is difficult and time consuming. A faster method is necessary to prevent exposure of susceptible patients to contaminated water. The objective of this study was to develop a molecular technique for direct detection of Fusarium in water. A direct DNA extraction method from water was developed and coupled to a genus-specific PCR, to detect 3 species of Fusarium (verticillioides, oxysporum and solani). The detection limits were 10 cells/L and 1 cell/L for the molecular and culture methods, respectively. To our knowledge, this is the first method developed to detect Fusarium directly from water.

  2. Biological control of Fusarium moniliforme in maize.

    PubMed Central

    Bacon, C W; Yates, I E; Hinton, D M; Meredith, F

    2001-01-01

    Fusarium moniliforme Sheldon, a biological species of the mating populations within the (italic)Gibberella fujikuroi species complex, i.e., population A [= G. moniliformis (Sheld.) Wineland], is an example of a facultative fungal endophyte. During the biotrophic endophytic association with maize, as well as during saprophytic growth, F. moniliforme produces the fumonisins. The fungus is transmitted vertically and horizontally to the next generation of plants via clonal infection of seeds and plant debris. Horizontal infection is the manner by which this fungus is spread contagiously and through which infection occurs from the outside that can be reduced by application of certain fungicides. The endophytic phase is vertically transmitted. This type infection is important because it is not controlled by seed applications of fungicides, and it remains the reservoir from which infection and toxin biosynthesis takes place in each generation of plants. Thus, vertical transmission of this fungus is just as important as horizontal transmission. A biological control system using an endophytic bacterium, Bacillus subtilis, has been developed that shows great promise for reducing mycotoxin accumulation during the endophytic (vertical transmission) growth phase. Because this bacterium occupies the identical ecological niche within the plant, it is considered an ecological homologue to F. moniliforme, and the inhibitory mechanism, regardless of the mode of action, operates on the competitive exclusion principle. In addition to this bacterium, an isolate of a species of the fungus Trichoderma shows promise in the postharvest control of the growth and toxin accumulation from F. moniliforme on corn in storage. PMID:11359703

  3. The influence of environmental factors on growth and interactions between Embellisia allii and Fusarium oxysporum f. sp. cepae isolated from garlic.

    PubMed

    Lee, Hyang Burm; Magan, Naresh

    2010-04-15

    Embellisia allii results in the formation of a bulb canker and black soot on the surface of different alliums and it has been frequently detected on garlic bulbs together with the spoilage fungus, Fusarium oxysporum f. sp. cepae, which causes bulb basal plate rot. In this study, the influence of water activity (a(w)) and temperature on mycelial growth of E. allii and F. oxysporum f. sp. cepae, conidial size and sporulation of E. allii, interactions between E. allii and F. oxysporum f. sp. cepae, Index of Dominance (I(D)), and in situ virulence on garlic were examined. Mycelial growth of E. allii was optimal (5.97 mm/day) at 0.995 a(w) and 25 degrees C, slower at 30 degrees C. However, almost no growth occurred at 0.937 a(w)/30 degrees C. F. oxysporum f. sp. cepae grew faster than E. allii, (6.3-7.4mm/day) at 30 degrees C. Interactions between E. allii and F. oxysporum f. sp. cepae were influenced by a(w) and temperature. Sporulation of E. allii was more abundant on PDA than on MEA, especially at high a(w) (0.995) and low temperature (20 degrees C), but almost no sporulation occurred at 30 degrees C regardless of nutritional medium or a(w) level. The spore length of E. allii was longer on PDA than MEA, and was significantly influenced by water availability. F. oxysporum f. sp. cepae was competitive against E. allii and had a higher I(D) value in comparison with E. allii especially at a higher temperature (30 degrees C). In situ virulence tests showed that E. allii was weakly virulent on the garlic bulb cloves while that of F. oxysporum f. sp. cepae was highly dependent on a(w).

  4. Sensitive detection of Fusarium circinatum in pine seed by combining an enrichment procedure with a real-time polymerase chain reaction using dual-labeled probe chemistry.

    PubMed

    Ioos, Renaud; Fourrier, Céline; Iancu, Gabriela; Gordon, Thomas R

    2009-05-01

    Fusarium circinatum is the causal agent of pitch canker disease on numerous Pinus spp. This aggressive fungus may infect pine seed cryptically and, therefore, can easily be spread long distances by the seed trade. F. circinatum has recently been listed as a quarantine organism in numerous countries throughout the world, which prompted the development of a specific and sensitive tool for the detection of this pathogen in conifer seed. A new detection protocol for F. circinatum based on a biological enrichment step followed by a real-time polymerase chain reaction (PCR) assay was developed. Several enrichment protocols were compared and a 72-h incubation of the seed with potato dextrose broth was the most efficient technique to increase F. circinatum biomass before DNA extraction. The relative accuracy, specificity, and sensitivity of the real-time PCR assay was evaluated in comparison with a previously published conventional PCR test on 420 seed DNA extracts. The real-time PCR described here proved to be highly specific and significantly more sensitive than the conventional PCR, and enabled the detection of F. circinatum in samples artificially contaminated with less than 1/1,000 infected seed, as well as in naturally infected samples. Last, in order to routinely check the quality of the seed DNA extracts, a primer-probe combination that targets a highly conserved region within the 18S ribosomal DNA in plants or fungi was successfully developed. This assay allows for quick and reliable detection of F. circinatum in seed, which can help to prevent long-distance spread of the pathogen via contaminated seed lots.

  5. Insights into natural products biosynthesis from analysis of 490 polyketide synthases from Fusarium.

    PubMed

    Brown, Daren W; Proctor, Robert H

    2016-04-01

    Species of the fungus Fusarium collectively cause disease on almost all crop plants and produce numerous natural products (NPs), including some of the mycotoxins of greatest concern to agriculture. Many Fusarium NPs are derived from polyketide synthases (PKSs), large multi-domain enzymes that catalyze sequential condensation of simple carboxylic acids to form polyketides. To gain insight into the biosynthesis of polyketide-derived NPs in Fusarium, we retrieved 488 PKS gene sequences from genome sequences of 31 species of the fungus. In addition to these apparently functional PKS genes, the genomes collectively included 81 pseudogenized PKS genes. Phylogenetic analysis resolved the PKS genes into 67 clades, and based on multiple lines of evidence, we propose that homologs in each clade are responsible for synthesis of a polyketide that is distinct from those synthesized by PKSs in other clades. The presence and absence of PKS genes among the species examined indicated marked differences in distribution of PKS homologs. Comparisons of Fusarium PKS genes and genes flanking them to those from other Ascomycetes provided evidence that Fusarium has the genetic potential to synthesize multiple NPs that are the same or similar to those reported in other fungi, but that have not yet been reported in Fusarium. The results also highlight ways in which such analyses can help guide identification of novel Fusarium NPs and differences in NP biosynthetic capabilities that exist among fungi.

  6. Suppression of Fusarium wilt of cucumber by ammonia gas fumigation via reduction of Fusarium population in the field.

    PubMed

    Zhao, Jun; Mei, Zhong; Zhang, Xu; Xue, Chao; Zhang, Chenzhi; Ma, Tengfei; Zhang, Shusheng

    2017-02-23

    Cucumber plants subjected to consecutive monoculture for 9 years were found to suffer from severe Fusarium wilt disease, caused by the soil-borne fungus Fusarium oxysporum f. sp. Cucumerinum J. H. Owen. In the present study, greenhouse experiments were performed to evaluate the influence of ammonia gas fumigation on Fusarium wilt suppression, fungal abundance and fungal community composition. Results showed that ammonia gas fumigation remarkably reduced disease incidence from 80% to 27%, resulting in a four-fold increase in yield, compared to the control. Total fungal abundance declined dramatically after fumigation and reached the lowest level at day 32, at 243 times lower than the control. Moreover, fumigation significantly increased soil fungal diversity, though it also decreased considerably coinciding with cucumber growth. Fumigation also significantly altered soil fungal community composition, relative to the control. Fusarium was strongly inhibited by fumigation in both relative abundance (3.8 times lower) and targeted quantification (a decrease of 167 fold). Collectively, the application of ammonia gas fumigation to control Fusarium wilt of cucumber resulted in a re-assembly of the fungal community to resemble that of a non-disease conducive consortium. Additional strategies, such as bioorganic fertilizer application, may still be required to develop sustainable disease suppression following fumigation.

  7. Suppression of Fusarium wilt of cucumber by ammonia gas fumigation via reduction of Fusarium population in the field

    PubMed Central

    Zhao, Jun; Mei, Zhong; Zhang, Xu; Xue, Chao; Zhang, Chenzhi; Ma, Tengfei; Zhang, Shusheng

    2017-01-01

    Cucumber plants subjected to consecutive monoculture for 9 years were found to suffer from severe Fusarium wilt disease, caused by the soil-borne fungus Fusarium oxysporum f. sp. Cucumerinum J. H. Owen. In the present study, greenhouse experiments were performed to evaluate the influence of ammonia gas fumigation on Fusarium wilt suppression, fungal abundance and fungal community composition. Results showed that ammonia gas fumigation remarkably reduced disease incidence from 80% to 27%, resulting in a four-fold increase in yield, compared to the control. Total fungal abundance declined dramatically after fumigation and reached the lowest level at day 32, at 243 times lower than the control. Moreover, fumigation significantly increased soil fungal diversity, though it also decreased considerably coinciding with cucumber growth. Fumigation also significantly altered soil fungal community composition, relative to the control. Fusarium was strongly inhibited by fumigation in both relative abundance (3.8 times lower) and targeted quantification (a decrease of 167 fold). Collectively, the application of ammonia gas fumigation to control Fusarium wilt of cucumber resulted in a re-assembly of the fungal community to resemble that of a non-disease conducive consortium. Additional strategies, such as bioorganic fertilizer application, may still be required to develop sustainable disease suppression following fumigation. PMID:28230182

  8. DNA barcoding, MALDI-TOF, and AFLP data support Fusarium ficicrescens as a distinct species within the Fusarium fujikuroi species complex.

    PubMed

    Al-Hatmi, Abdullah M S; Mirabolfathy, Mansoureh; Hagen, Ferry; Normand, Anne-Cécile; Stielow, J Benjamin; Karami-Osbo, Rouhollah; van Diepeningen, Anne D; Meis, Jacques F; de Hoog, G Sybren

    2016-02-01

    The Fusarium fujikuroi species complex (FFSC) is one of the most common groups of fusaria associated with plant diseases, mycotoxin production and traumatic and disseminated human infections. Here we present the description and taxonomy of a new taxon, Fusarium ficicrescens sp. nov., collected from contaminated fig fruits in Iran. Initially this species was identified as Fusarium andiyazi by morphology. In the present study the species was studied by multilocus sequence analysis, amplified fragment length polymorphism (AFLP), matrix-assisted laser desorption ionization time-of-flight mass spectrometry (MALDI-TOF MS) and phenotypic characters. Multilocus analyses were based on translation elongation factor 1α (TEF1), RNA polymerase subunit (RPB2) and beta-tubulin (BT2) and proved F. ficicrescens as a member of the FFSC. Phylogenetic analysis showed that the fungus is closely related to Fusarium lactis, Fusarium ramigenum, and Fusarium napiforme; known plant pathogens, mycotoxin producers, and occasionally occurring multidrug resistant opportunists. The new species differed by being able to grow at 37 °C and by the absence of mycotoxin production. TEF1 was confirmed as an essential barcode for identifying Fusarium species. In addition to TEF1, we evaluated BT2 and RPB2 in order to provide sufficient genetic and species boundaries information for recognition of the novel species.

  9. Seed treatment with live or dead Fusarium verticillioides equivalently reduces the severity of subsequent stalk rot

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Fusarium verticillioides is a widely distributed fungus that can associate with maize as a deleterious pathogen and an advantageous endophyte. Here, we show that seed treatment with live F.verticillioides enhances maize resistance to secondary stalk rot infection, and demonstrate that dead F.vertici...

  10. Exploring the role of trehalose metabolism in resistance to oxidative and desiccation stress in Fusarium verticillioides

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Fusarium verticillioides is a pathogenic filamentous fungus that primarily affects maize. We are exploring stress response mechanisms in F. verticillioides, particularly the role of trehalose, a disaccharide known to be involved in the ability of several organisms to withstand desiccation or drought...

  11. EBR1 genomic expansion and its role in virulence of Fusarium species

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Genome sequencing of Fusarium oxysporum revealed that pathogenic forms of this fungus harbor supernumerary chromosomes with a wide variety of genes, many of which likely encode traits required for pathogenicity or niche specialization. Specific transcription factor (TF) gene families are expanded on...

  12. Food Fight: Fungal Foe Frustration (Fusarium verticillioides vs. the world of xenobiotics)

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Fusarium verticillioides infects maize and produces the fumonisin mycotoxins. The genome of the fungus encodes approximately 30 proteins containing beta-lactamase domains that are roughly evenly split between two families, metallo beta-lactamases and cephalosporinases. In bacteria beta-lactamases ar...

  13. Comparative genomics and transcriptomics of sexual development in a nematode-associated strain of Fusarium neocosmosporiellum

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Fusarium neocosmosporiellum (formerly Neocosmospora vasinfecta) is a ubiquitous saprobic fungus that has been isolated from plants, fungi, nematodes, dung and soil. This homothallic species is nested in a clade within the F. solani species complex near a lineage of fusaria farmed by ambrosia beetles...

  14. Nitric oxide detoxification by Fusarium verticillioides flavohemoglobin and role in pathogenicity of maize

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Fusarium verticillioides is a non-obligate plant pathogen of maize causing a number of specific diseases, including root rot, kernel rot, seed rot, stalk rot, and seedling blight. The saprophytic nature of this fungus, its production of the mycotoxin fumonisin, and complex relationship maize puts t...

  15. Genes, Gene Clusters, and Biosynthesis of Trichothecenes and Fumonisins in Fusarium

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Trichothecenes and fumonisins are mycotoxins produced by Fusarium, a filamentous fungus that can cause disease on some crop plants, including corn, rice, and wheat. Research on the genetics and biochemistry of trichothecene and fumonisin biosynthesis has provided important insights into the genetic...

  16. Candidate effector proteins of the necrotrophic apple canker pathogen Valsa mali can suppress BAX-induced PCD

    PubMed Central

    Li, Zhengpeng; Yin, Zhiyuan; Fan, Yanyun; Xu, Ming; Kang, Zhensheng; Huang, Lili

    2015-01-01

    Canker caused by the Ascomycete Valsa mali is the most destructive disease of apple in Eastern Asia, resulting in yield losses of up to 100%. This necrotrophic fungus induces severe necrosis on apple, eventually leading to the death of the whole tree. Identification of necrosis inducing factors may help to unravel the molecular bases for colonization of apple trees by V. mali. As a first step toward this goal, we identified and characterized the V. mali repertoire of candidate effector proteins (CEPs). In total, 193 secreted proteins with no known function were predicted from genomic data, of which 101 were V. mali-specific. Compared to non-CEPs predicted for the V. mali secretome, CEPs have shorter sequence length and a higher content of cysteine residues. Based on transient over-expression in Nicotiana benthamiana performed for 70 randomly selected CEPs, seven V. mali Effector Proteins (VmEPs) were shown to significantly suppress BAX-induced PCD. Furthermore, targeted deletion of VmEP1 resulted in a significant reduction of virulence. These results suggest that V. mali expresses secreted proteins that can suppress PCD usually associated with effector-triggered immunity (ETI). ETI in turn may play an important role in the V. mali–apple interaction. The ability of V. mali to suppress plant ETI sheds a new light onto the interaction of a necrotrophic fungus with its host plant. PMID:26284095

  17. 78 FR 58992 - Notice of Request for Extension of Approval of an Information Collection; Citrus Canker...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-09-25

    ... Collection; Citrus Canker; Interstate Movement of Regulated Nursery Stock and Fruit From Quarantined Areas... nursery stock and fruit from quarantined areas to prevent the spread of citrus canker. DATES: We will...: For information on the regulations for the interstate movement of regulated nursery stock and...

  18. Phomopsis stem canker: a re-emerging threat to sunflowers (Helianthus annuus) in the United States

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Phomopsis stem canker frequently causes yield reductions on sunflowers (Helianthus annuus L.) on several continents, including Australia, Russia, Europe and North America. Between 2001 and 2012, the incidence of Phomopsis stem canker has increased 16 fold in the Northern Great Plains of the United...

  19. Phomopsis Stem Canker: A Reemerging Threat to Sunflower (Helianthus annuus) in the United States

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Phomopsis stem canker causes yield reductions on sunflower (Helianthus annuus L.) on several continents, including Australia, Europe, and North America. In the United States, Phomopsis stem canker incidence has increased 16-fold in the Northern Great Plains between 2001 and 2012. Although Diaporthe ...

  20. Effect of windbreaks on wind speed and canker incidence and severity on grapefruit

    Technology Transfer Automated Retrieval System (TEKTRAN)

    For fresh grapefruit the goal is to maximize pack-out by minimizing canker lesions on fruit. The objective of these trials was to determine the relationship between wind speed and incidence and severity of canker on 5 to 7 yr-old Ruby Red grapefruit trees located in two trial blocks (~4.5 ha) surrou...

  1. Effect of windbreaks on wind speed and citrus canker incidence on grapefruit

    Technology Transfer Automated Retrieval System (TEKTRAN)

    For fresh grapefruit the goal is to maximize pack-out by minimizing canker lesions on fruit. The objective of these trials was to determine the relationship between wind speed and incidence and severity of citrus canker on 5 to 7 yr-old ‘Ruby Red’ grapefruit trees located in two trial blocks (~4.5 h...

  2. First report of citrus canker caused by Xanthomonas citri in Somalia

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Xanthomonas citri, causal agent of citrus canker, has been reported in several countries in Africa, but not Somalia. During 2006 and 2007, hyperplasia-type lesions, often surrounded by a water-soaked margin and yellow halo, typical of citrus canker caused by X. citri, were found on 8-10 year-old gr...

  3. Identification of Fusarium solani species complex from infected zebrafish (Danio rerio).

    PubMed

    Ke, Xiaoli; Lu, Maixin; Wang, Jianguo

    2016-11-01

    Although Fusarium sp. infections have been reported in aquatic invertebrates, studies of Fusarium spp. as fish pathogens remain very limited. In our study, a fungus was isolated from diseased zebrafish (Danio rerio). DNA sequence analysis of the fungus, based on a partial region of the translation elongation factor 1α gene (EF-1α), the internal transcribed spacer region and domains D1 and D2 of the large subunit of the ribosomal RNA gene (ITS plus LSU), and the RNA polymerase II subunit gene (RPB2), showed 99.9-100% homology to Fusarium solani species complex sequences. Multilocus sequence typing analysis based on 3-locus haplotypes (EF-1α, ITS plus LSU, and RPB2) suggests that the isolated strain was type 3+4-P. Challenge experiments showed that this organism could be pathogenic to zebrafish, but usually does not infect healthy subjects under normal circumstances.

  4. Cutinase of Fusarium solani F. sp. pisi: mechanism of induction and relatedness to other Fusarium species

    SciTech Connect

    Woloshuk, C.P.

    1986-01-01

    Three studies were made on the extracellular cutinase of the phytopathogenic fungus Fusarium solani f. sp. pisi. I. The production of cutinase was found to be induced in spores of F. solani f. sp. pisi, strain T-8, by cutin and cutin hydrolysate. Fractionation and analysis of the cutin hydrolysate indicated that dihydroxy-C/sub 16/ acid and trihydroxy-C/sub 18/ acid were the cutin monomers most active for inducing cutinase. Measurement of cutinase-specific RNA levels by dot-blot hybridization with a (/sup 32/P)-labeled cutinase cDNA showed that the cutinase gene transcripts could be detected within 15 min after addition of the inducers. The results indicated that the fungal spores have the capacity to recognize the unique monomer components of the plant cuticle and rapidly respond by the synthesis of cutinase. II. Analysis of the genomic DNA's of seven strains of F. solani f. sp. pisi indicated that both high and low cutinase-producing strains contain at least one copy of the cutinase structural gene and a homologous promoter region. The data suggest a different promoter sequence exists in these additional copies. III. Relatedness of five phytopathogenic Fusarium species to F. solani f. sp. pisi was determined by their cutinase antigenic properties and gene homologies of cutinase cDNA from F. solani f. sp. pisi. The results suggest that formae specialis of F. solani are phylogenetically identical and that F. solani is quite distinct from the other Fusarium species tested.

  5. A major QTL associated with Fusarium oxysporum race 1 resistance identified in genetic populations derived from closely related watermelon lines using selective genotyping and genotyping-by-sequencing for SNP discovery

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Fusarium wilt is a major soil-borne disease of watermelon caused by the fungus Fusarium oxysporum Schlechtend.:Fr. f. sp. niveum (E.F. Sm.) W.C. Snyder & H.N. Hans (Fon). In this study, a genetic population of 186 F3 families (24 plants in each family) exhibited continuous distribution for Fon race ...

  6. A nonpathogenic Fusarium oxysporum strain enhances phytoextraction of heavy metals by the hyperaccumulator Sedum alfredii Hance.

    PubMed

    Zhang, Xincheng; Lin, Li; Chen, Mingyue; Zhu, Zhiqiang; Yang, Weidong; Chen, Bao; Yang, Xiaoe; An, Qianli

    2012-08-30

    Low biomass and shallow root systems limit the application of heavy metal phytoextraction by hyperaccumulators. Plant growth-promoting microbes may enhance hyperaccumulators'phytoextraction. A heavy metal-resistant fungus belonged to the Fusarium oxysporum complex was isolated from the Zn/Cd co-hyperaccumulator Sedum alfredii Hance grown in a Pb/Zn mined area. This Fusarium fungus was not pathogenic to plants but promoted host growth. Hydroponic experiments showed that 500 μM Zn(2+) or 50 μM Cd(2+) combined with the fungus increased root length, branches, and surface areas, enhanced nutrient uptake and chlorophyll synthesis, leading to more vigorous hyperaccumulators with greater root systems. Soil experiments showed that the fungus increased root and shoot biomass and S. alfredii-mediated heavy metal availabilities, uptake, translocation or concentrations, and thus increased phytoextraction of Zn (144% and 44%), Cd (139% and 55%), Pb (84% and 85%) and Cu (63% and 77%) from the original Pb/Zn mined soil and a multi-metal contaminated paddy soil. Together, the nonpathogenic Fusarium fungus was able to increase S. alfredii root systems and function, metal availability and accumulation, plant biomass, and thus phytoextraction efficiency. This study showed a great application potential for culturable indigenous fungi other than symbiotic mycorrhizas to enhance the phytoextraction by hyperaccumulators.

  7. [Equine exudative canker: an (auto-)immune disease?].

    PubMed

    Jongbloets, A M C; Sloet van Oldruitenborgh-Oosterbaan, M M; Meeus, P J H M; Back, W

    2005-02-15

    Equine canker is a chronic, hyperplastic, exudative pododermatitis affecting one or more feet. Although many causes and treatments have been suggested, the cause of the disease is still unknown and most probably multifactorial. Local treatments include radical surgical debridement of the diseased hoof tissue and application of caustic substances, antibiotics, and pressure bandaging. Nevertheless, the number of recurrences is high (45%). This article presents a 3-year-old New Forest pony-cross mare in which all horny structures (frogs, coronets, spurs, chestnuts) of all feet were affected. Bacteriological and fungal cultures of the frogs were found negative for the pathogens tested. Papilloma virus was not found. Clinical findings raised the hypothesis that the non-specific hyperplastic inflammation of these horn-like structures might have been caused by an (auto-)immune reaction. On the basis of the clinical findings, the pony was treated with surgical debridement of the frogs of a diagonal pair of feet and oral administration of prednisolone (1 mg/kg sid). The frogs, coronets, spurs, and chestnuts of all four feet healed completely within 8 weeks, thus making an (auto-)immune reaction more likely. In conclusion, this case report raised the hypothesis that an aspecific, hyperplastic inflammation of all four feet ('equine canker') and other horny structures may be caused by an (auto-)immune reaction, and that corticosteroids (prednisolone 1 mg/kg sid per os) are effective as treatment.

  8. Fusarium Wilt of Banana.

    PubMed

    Ploetz, Randy C

    2015-12-01

    Banana (Musa spp.) is one of the world's most important fruits. In 2011, 145 million metric tons, worth an estimated $44 billion, were produced in over 130 countries. Fusarium wilt (also known as Panama disease) is one of the most destructive diseases of this crop. It devastated the 'Gros Michel'-based export trades before the mid-1900s, and threatens the Cavendish cultivars that were used to replace it; in total, the latter cultivars are now responsible for approximately 45% of all production. An overview of the disease and its causal agent, Fusarium oxysporum f. sp. cubense, is presented below. Despite a substantial positive literature on biological, chemical, or cultural measures, management is largely restricted to excluding F. oxysporum f. sp. cubense from noninfested areas and using resistant cultivars where the pathogen has established. Resistance to Fusarium wilt is poor in several breeding targets, including important dessert and cooking cultivars. Better resistance to this and other diseases is needed. The history and impact of Fusarium wilt is summarized with an emphasis on tropical race 4 (TR4), a 'Cavendish'-killing variant of the pathogen that has spread dramatically in the Eastern Hemisphere.

  9. Inhibition of Fusarium graminearum growth in flour gel cultures by hexane-soluble compounds from oat (Avena sativa L.) flour.

    PubMed

    Doehlert, Douglas C; Rayas-Duarte, Patricia; McMullen, Michael S

    2011-12-01

    Fusarium head blight, incited by the fungus Fusarium graminearum, primarily affects wheat (Triticum aestivum) and barley (Hordeum vulgarum), while oat (Avena sativa) appears to be more resistant. Although this has generally been attributed to the open panicle of oats, we hypothesized that a chemical component of oats might contribute to this resistance. To test this hypothesis, we created culture media made of wheat, barley, and oat flour gels (6 g of flour in 20 ml of water, gelled by autoclaving) and inoculated these with plugs of F. graminearum from actively growing cultures. Fusarium growth was measured from the diameter of the fungal plaque. Plaque diameter was significantly smaller on oat flour cultures than on wheat or barley cultures after 40 to 80 h of growth. Ergosterol concentration was also significantly lower in oat cultures than in wheat cultures after growth. A hexane extract from oats added to wheat flour also inhibited Fusarium growth, and Fusarium grew better on hexane-defatted oat flour. The growth of Fusarium on oat flour was significantly and negatively affected by the oil concentration in the oat, in a linear relationship. A hexane-soluble chemical in oat flour appears to inhibit Fusarium growth and might contribute to oat's resistance to Fusarium head blight. Oxygenated fatty acids, including hydroxy, dihydroxy, and epoxy fatty acids, were identified in the hexane extracts and are likely candidates for causing the inhibition.

  10. Development of a qPCR technique to screen for resistance to Asiatic citrus canker

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Asiatic citrus canker (Acc) (causal organism Xanthomonas citri subspc. citri (Xcc) is threatening sustainability of the Florida citrus industry. Resistant cultivars, whether developed through conventional breeding or genetic transformation, will be he best solution for dealint with Acc. In Florida...

  11. Mechanistic aspects of biosynthesis of silver nanoparticles by several Fusarium oxysporum strains

    PubMed Central

    Durán, Nelson; Marcato, Priscyla D; Alves, Oswaldo L; De Souza, Gabriel IH; Esposito, Elisa

    2005-01-01

    Extracellular production of metal nanoparticles by several strains of the fungus Fusarium oxysporum was carried out. It was found that aqueous silver ions when exposed to several Fusarium oxysporum strains are reduced in solution, thereby leading to the formation of silver hydrosol. The silver nanoparticles were in the range of 20–50 nm in dimensions. The reduction of the metal ions occurs by a nitrate-dependent reductase and a shuttle quinone extracellular process. The potentialities of this nanotechnological design based in fugal biosynthesis of nanoparticles for several technical applications are important, including their high potential as antibacterial material. PMID:16014167

  12. He said, she said: mRNA sequencing identifies specificity in metabolic response to Bacillus mojavensis lipopeptides in Fusarium verticillioides

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Fusarium verticillioides is a mycotoxigenic fungus capable of both pathogenic and asymptomatic endophytic lifestyles in maize; such intimate association renders efficient chemical control cost-prohibitive. Bacillus mojavensis RRC101 is a maize endophyte demonstrating both in vitro antagonism of F. v...

  13. Discovery and toxicity assessment of a novel type A trichothecene produced by US isolates of Fusarium graminearum

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The filamentous fungus Fusarium graminearum shows a widespread occurrence across temperate regions of the world and can produce several mycotoxins on almost every cereal. A large-scale survey of F. graminearum (sensu stricto) on wheat in the northern United States was conducted to investigate the po...

  14. Genome-wide analysis and functional characterization of candidate effector proteins potentially involved in Fusarium graminearum-wheat interactions

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Fungal pathogens often produce certain small secreted cysteine-rich proteins (SSCPs) during pathogenesis that may function in triggering resistance or susceptibility in specific host plants. We have identified a total of 190 SSCPs encoded in the genome of the wheat scab fungus Fusarium graminearum a...

  15. Gene clusters FDB1 and FDB2 in Fusarium verticillioides were acquired through multiple horizontal gene transfer events

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The corn pathogen Fusarium verticillioides is of significant importance because of its deleterious effects on plant and animal health and on the quality of their products due to mycotoxin contamination. The fungus is known to metabolize antimicrobial compounds produced by corn using genes within t...

  16. Genotype Response of Soybean (Glycine max) Whole Plants and Hairy Roots to Fusarium solani f. sp. glycines Infection

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Fusarium solani f. sp. Glycines, a soilborne fungus, infects soybean roots and causes sudden death syndrome. The response of 13 soybean genotypes to the pathogen infection was tested with potted greenhouse grown plants and with cultured hairy roots. The taproots of all genotypes grown plants measure...

  17. Genetic differentiation and spatial structure of Geosmithia morbida, the causal agent of thousand cankers disease in black walnut (Juglans nigra).

    PubMed

    Hadziabdic, Denita; Vito, Lisa M; Windham, Mark T; Pscheidt, Jay W; Trigiano, Robert N; Kolarik, Miroslav

    2014-05-01

    The main objectives of this study were to evaluate genetic composition of Geosmithia morbida populations in the native range of black walnut and provide a better understanding regarding demography of the pathogen. The fungus G. morbida, and the walnut twig beetle, Pityophthorus juglandis, have been associated with a disease complex of black walnut (Juglans nigra) known as thousand cankers disease (TCD). The disease is manifested as branch dieback and canopy loss, eventually resulting in tree death. In 2010, the disease was detected in black walnut in Tennessee, and subsequently in Virginia and Pennsylvania in 2011 and North Carolina in 2012. These were the first incidences of TCD east of Colorado, where the disease has been established for more than a decade on indigenous walnut species. A genetic diversity and population structure study of 62 G. morbida isolates from Tennessee, Pennsylvania, North Carolina and Oregon was completed using 15 polymorphic microsatellite loci. The results revealed high haploid genetic diversity among seven G. morbida populations with evidence of gene flow, and significant differentiation among two identified genetic clusters. There was a significant correlation between geographic and genetic distance. Understanding the genetic composition and demography of G. morbida can provide valuable insight into recognizing factors affecting the persistence and spread of an invasive pathogen, disease progression, and future infestation predictions. Overall, these data support the hypotheses of two separate, highly diverse pathogen introductions into the native range of black walnut.

  18. Contribution of the endogeic earthworm species Aporrectodea caliginosa to the degradation of deoxynivalenol and Fusarium biomass in wheat straw.

    PubMed

    Wolfarth, Friederike; Schrader, Stefan; Oldenburg, Elisabeth; Weinert, Joachim

    2011-08-01

    In arable fields managed by conservation tillage combined with crop residue mulching, plant pathogen repression is an important ecosystem service to prevent cultivated plants from fungal diseases and mycotoxin contamination. A laboratory microcosm study was conducted to investigate the contribution of the endogeic, geophagous earthworm species Aporrectodea caliginosa as a secondary decomposer to the reduction of the phytopathogenic fungus Fusarium culmorum and its mycotoxin deoxynivalenol (DON) in wheat straw residues. After 5 weeks experimental time, the Fusarium biomass and the DON concentration in aboveground straw were reduced considerably to the same extent both in presence and absence of A. caliginosa. Another substantial reduction of Fusarium biomass and DON concentration was found in belowground straw, which A. caliginosa had buried into the soil. Thus, we conclude that the particular contribution of secondary decomposers like A. caliginosa to the degradation of phytopathogenic fungi like Fusarium species and their mycotoxins like DON in the soil systems has to be assessed as minor.

  19. Isolation and characterization of two mitoviruses and a putative alphapartitivirus from Fusarium spp.

    PubMed

    Osaki, Hideki; Sasaki, Atsuko; Nomiyama, Koji; Sekiguchi, Hiroyuki; Tomioka, Keisuke; Takehara, Toshiaki

    2015-06-01

    The filamentous fungus Fusarium spp. includes several important plant pathogens. We attempted to reveal presence of double-stranded (ds) RNAs in the genus. Thirty-seven Fusarium spp. at the MAFF collection were analyzed. In the strains of Fusarium coeruleum, Fusarium globosum and Fusarium solani f. sp. pisi, single dsRNA bands were detected. The strains of F. coeruleum and F. solani f. sp. pisi cause potato dry rot and mulberry twig blight, respectively. Sequence analyses revealed that dsRNAs in F. coeruleum and F. globosum consisted of 2423 and 2414 bp, respectively. Using the fungal mitochondrial translation table, the positive strands of these cDNAs were found to contain single open reading frames with the potential to encode a protein of putative 757 and 717 amino acids (molecular mass 88.5 and 84.0 kDa, respectively), similar to RNA-dependent RNA polymerases of members of the genus Mitovirus. These dsRNAs in F. coeruleum and F. globosum were assigned to the genus Mitovirus (family Narnaviridae), and these two mitoviruses were designated as Fusarium coeruleum mitovirus 1 and Fusarium globosum mitovirus 1. On the other hand, a positive strand of cDNA (1950 bp) from dsRNA in F. solani f. sp. pisi contained an ORF potentially encoding a putative RdRp of 608 amino acids (72.0 kDa). The putative RdRp was shown to be related to those of members of the genus of Alphapartitivirus (family Partitiviridae). We coined the name Fusarium solani partitivirus 2 for dsRNA in F. solani f. sp. pisi.

  20. A RALDH-like enzyme involved in Fusarium verticillioides development.

    PubMed

    Díaz-Sánchez, Violeta; Limón, M Carmen; Schaub, Patrick; Al-Babili, Salim; Avalos, Javier

    2016-01-01

    Retinaldehyde dehydrogenases (RALDHs) convert retinal to retinoic acid, an important chordate morphogen. Retinal also occurs in some fungi, such as Fusarium and Ustilago spp., evidenced by the presence of rhodopsins and β-carotene cleaving, retinal-forming dioxygenases. Based on the assumption that retinoic acid may also be formed in fungi, we searched the Fusarium protein databases for RALDHs homologs, focusing on Fusarium verticillioides. Using crude lysates of Escherichia coli cells expressing the corresponding cDNAs, we checked the capability of best matches to convert retinal into retinoic acid in vitro. Thereby, we identified an aldehyde dehydrogenase, termed CarY, as a retinoic acid-forming enzyme, an activity that was also exerted by purified CarY. Targeted mutation of the carY gene in F. verticillioides resulted in alterations of mycelia development and conidia morphology in agar cultures, and reduced capacity to produce perithecia as a female in sexual crosses. Complementation of the mutant with a wild-type carY allele demonstrated that these alterations are caused by the lackof CarY. However, retinoic acid could not be detected by LC-MS analysis either in the wild type or the complemented carY strain in vivo, making elusive the connection between CarY enzymatic activity and retinoic acid formation in the fungus.

  1. Oak Tree Canker Disease Supports Arthropod Diversity in a Natural Ecosystem

    PubMed Central

    Lee, Yong-Bok; An, Su Jung; Park, Chung Gyoo; Kim, Jinwoo; Han, Sangjo; Kwak, Youn-Sig

    2014-01-01

    Microorganisms have many roles in nature. They may act as decomposers that obtain nutrients from dead materials, while some are pathogens that cause diseases in animals, insects, and plants. Some are symbionts that enhance plant growth, such as arbuscular mycorrhizae and nitrogen fixation bacteria. However, roles of plant pathogens and diseases in natural ecosystems are still poorly understood. Thus, the current study addressed this deficiency by investigating possible roles of plant diseases in natural ecosystems, particularly, their positive effects on arthropod diversity. In this study, the model system was the oak tree (Quercus spp.) and the canker disease caused by Annulohypoxylon truncatum, and its effects on arthropod diversity. The oak tree site contained 44 oak trees; 31 had canker disease symptoms while 13 were disease-free. A total of 370 individual arthropods were detected at the site during the survey period. The arthropods belonged to 25 species, 17 families, and seven orders. Interestingly, the cankered trees had significantly higher biodiversity and richness compared with the canker-free trees. This study clearly demonstrated that arthropod diversity was supported by the oak tree canker disease. PMID:25288984

  2. Oak tree canker disease supports arthropod diversity in a natural ecosystem.

    PubMed

    Lee, Yong-Bok; An, Su Jung; Park, Chung Gyoo; Kim, Jinwoo; Han, Sangjo; Kwak, Youn-Sig

    2014-03-01

    Microorganisms have many roles in nature. They may act as decomposers that obtain nutrients from dead materials, while some are pathogens that cause diseases in animals, insects, and plants. Some are symbionts that enhance plant growth, such as arbuscular mycorrhizae and nitrogen fixation bacteria. However, roles of plant pathogens and diseases in natural ecosystems are still poorly understood. Thus, the current study addressed this deficiency by investigating possible roles of plant diseases in natural ecosystems, particularly, their positive effects on arthropod diversity. In this study, the model system was the oak tree (Quercus spp.) and the canker disease caused by Annulohypoxylon truncatum, and its effects on arthropod diversity. The oak tree site contained 44 oak trees; 31 had canker disease symptoms while 13 were disease-free. A total of 370 individual arthropods were detected at the site during the survey period. The arthropods belonged to 25 species, 17 families, and seven orders. Interestingly, the cankered trees had significantly higher biodiversity and richness compared with the canker-free trees. This study clearly demonstrated that arthropod diversity was supported by the oak tree canker disease.

  3. Development and validation of standard area diagrams as assessment aids for estimating the severity of citrus canker on unripe oranges

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Canker (caused by Xanthomonas citri subsp. citri) is an important disease of citrus in Brazil and elsewhere in the world, and can cause severe disease on the fruit. The severity of citrus canker of fruit must often be estimated visually. The objective of this research was to construct and validate s...

  4. Water balance altered in cucumber plants infected with Fusarium oxysporum f. sp. cucumerinum

    PubMed Central

    Wang, Min; Sun, Yuming; Sun, Guomei; Liu, Xiaokang; Zhai, Luchong; Shen, Qirong; Guo, Shiwei

    2015-01-01

    Fusarium wilt is caused by the infection and growth of the fungus Fusarium oxysporum in the xylem of host plants. The physiological responses of cucumbers that are infected with Fusarium oxysporum f. sp. cucumerinum (FOC) was studied in pot and hydroponic experiments in a greenhouse. The results showed that although water absorption and stem hydraulic conductance decreased markedly in infected plants, large amounts of red ink accumulated in the leaves of infected cucumber plants. The transpiration rate (E) and stomatal conductance (gs) of the infected plants were significantly reduced, but the E/gs was higher than healthy plants. We further found that there was a positive correlation between leaf membrane injury and E/gs, indicating that the leaf cell membrane injury increased the non-stomatal water loss from infected plants. The fusaric acid (FA), which was detected in the infected plant, resulted in damage to the leaf cell membranes and an increase in E/gs, suggesting that FA plays an important role in non-stomatal water loss. In conclusion, leaf cell membrane injury in the soil-borne Fusarium wilt of cucumber plants induced uncontrolled water loss from damaged cells. FA plays a critical role in accelerating the development of Fusarium wilt in cucumber plants. PMID:25579504

  5. Toxicity of abiotic stressors to Fusarium species: differences in hydrogen peroxide and fungicide tolerance.

    PubMed

    Nagygyörgy, Emese D; Kovács, Barbara; Leiter, Eva; Miskei, Márton; Pócsi, István; Hornok, László; Adám, Attila L

    2014-06-01

    Stress sensitivity of three related phytopathogenic Fusarium species (Fusarium graminearum, Fusarium oxysporum and Fusarium verticillioides) to different oxidative, osmotic, cell wall, membrane, fungicide stressors and an antifungal protein (PAF) were studied in vitro. The most prominent and significant differences were found in oxidative stress tolerance: all the three F. graminearum strains showed much higher sensitivity to hydrogen peroxide and, to a lesser extent, to menadione than the other two species. High sensitivity of F. verticillioides strains was also detectable to an azole drug, Ketoconazole. Surprisingly, no or limited differences were observed in response to other oxidative, osmotic and cell wall stressors. These results indicate that fungal oxidative stress response and especially the response to hydrogen peroxide (this compound is involved in a wide range of plant-fungus interactions) might be modified on niche-specific manner in these phylogenetically related Fusarium species depending on their pathogenic strategy. Supporting the increased hydrogen peroxide sensitivity of F. graminearum, genome-wide analysis of stress signal transduction pathways revealed the absence one CatC-type catalase gene in F. graminearum in comparison to the other two species.

  6. Water balance altered in cucumber plants infected with Fusarium oxysporum f. sp. cucumerinum.

    PubMed

    Wang, Min; Sun, Yuming; Sun, Guomei; Liu, Xiaokang; Zhai, Luchong; Shen, Qirong; Guo, Shiwei

    2015-01-12

    Fusarium wilt is caused by the infection and growth of the fungus Fusarium oxysporum in the xylem of host plants. The physiological responses of cucumbers that are infected with Fusarium oxysporum f. sp. cucumerinum (FOC) was studied in pot and hydroponic experiments in a greenhouse. The results showed that although water absorption and stem hydraulic conductance decreased markedly in infected plants, large amounts of red ink accumulated in the leaves of infected cucumber plants. The transpiration rate (E) and stomatal conductance (gs) of the infected plants were significantly reduced, but the E/gs was higher than healthy plants. We further found that there was a positive correlation between leaf membrane injury and E/gs, indicating that the leaf cell membrane injury increased the non-stomatal water loss from infected plants. The fusaric acid (FA), which was detected in the infected plant, resulted in damage to the leaf cell membranes and an increase in E/gs, suggesting that FA plays an important role in non-stomatal water loss. In conclusion, leaf cell membrane injury in the soil-borne Fusarium wilt of cucumber plants induced uncontrolled water loss from damaged cells. FA plays a critical role in accelerating the development of Fusarium wilt in cucumber plants.

  7. Detection of citrus canker and Huanglongbing using fluorescence imaging spectroscopy and support vector machine technique.

    PubMed

    Wetterich, Caio Bruno; Felipe de Oliveira Neves, Ruan; Belasque, José; Marcassa, Luis Gustavo

    2016-01-10

    Citrus canker and Huanglongbing (HLB) are citrus diseases that represent a serious threat to the citrus production worldwide and may cause large economic losses. In this work, we combined fluorescence imaging spectroscopy (FIS) and a machine learning technique to discriminate between these diseases and other ordinary citrus conditions that may be present at citrus orchards, such as citrus scab and zinc deficiency. Our classification results are highly accurate when discriminating citrus canker from citrus scab (97.8%), and HLB from zinc deficiency (95%). These results show that it is possible to accurately identify citrus diseases that present similar symptoms.

  8. Ethanol attracts scolytid beetles to Phytophthora ramorum cankers on coast live oak.

    PubMed

    Kelsey, Rick G; Beh, Maia M; Shaw, David C; Manter, Daniel K

    2013-04-01

    Ethanol in sapwood was analyzed along vertical transects, through small spot cankers and larger basal cankers, of Phytophthora ramorum-infected stems of Quercus agrifolia at three sites in California. Trees with large basal cankers, known to attract scolytid beetles, had a 4.3 times higher ethanol level than trees with spot cankers that attract fewer beetles. Ethanol concentrations inside cankers, where scolytid beetles preferentially attack, varied by about four orders of magnitude among samples, with a median level of 16.0 μg.g(-1) fresh mass. This concentration was 4.3 and 15.5 times greater, respectively, than the concentrations at 1 cm or 15-30 cm outside the canker boundaries. In the laboratory, we demonstrated that ethanol escaped through the bark of a Q. garryana log just 3 days after it was added to the sapwood. At the three study sites, traps baited with ethanol captured more Xyleborinus saxesenii, Pseudopityophthorus pubipennis, and Monarthrum dentiger (all Coleoptera: Curculionidae: Scolytinae) than traps baited with ethanol plus (-)-α-pinene, or ethanol plus 4-allylanisole (4AA). Logs of Q. agrifolia with a 50 % ethanol solution added to the sapwood were placed at the study sites, with or without additional bark treatments above the ethanol. The number of scolytid beetle gallery holes above the ethanol-infused sapwood was 4.4 times greater than that on the opposite side of the log where no ethanol was added. Attachment of ultra-high release (-)-α-pinene pouches to the bark surface above the 50 % ethanol solution reduced scolytid attacks to a density of 19.1 % that of logs without this treatment. We conclude that ethanol in P. ramorum cankers functions as a primary host attractant for scolytid beetles and is an important link in colonization of these cankers and accelerated mortality of Q. agrifolia. The results of this research shed light on the chemical ecology behind the focused scolytid attacks on P. ramorum-infected coast live oaks, and lay the

  9. Ecological distribution of Fusarium solani and its opportunistic action related to mycotic keratitis in Cali, Colombia.

    PubMed Central

    Cuero, R G

    1980-01-01

    Corneal ulcera in patients treated at the University Hospital Cali, Colombia have been attributed to the fungus Fusarium solani, which was isolated from patients' eyes by deep scraping. The fungus, which was characterized by culture and morphology, was found to grow well at 37 degrees C in Sabouraud and potato dextrose agars and in liquid asparagine medium, in which it produced very few spores; at 40 degrees C, it survived for 3 weeks. Different levels of pathogenicity were shown by the fungus when 3-week-old bean, corn, and tomato plants were inoculated. Controlled experiments in which an inoculum of F. solani was instilled in rabbit eyes were also carried out; it evoked a clinical reaction producing irritation and erythema. The F. solani isolated from eyes was the same species as that isolated by an agar plate method with Fusarium-selective medium from sugar cane, bean, tomato, or corn fields throughout December 1976 to November 1977. Nonfarming areas and urban sites were also air sampled, but only a few (less than 1%) colonies of F. solani were isolated at one of four sites. A preliminary attempt to identify the physiologically active substance of the fungus was carried out through chemical extraction, thin-layer chromatography, and ultraviolet and infrared spectra analysis. Images PMID:7217337

  10. Agrobacterium-mediated transformation of Fusarium proliferatum.

    PubMed

    Bernardi-Wenzel, J; Quecine, M C; Azevedo, J L; Pamphile, J A

    2016-06-03

    Fusarium proliferatum is an important pathogen that is associated with plant diseases and primarily affects aerial plant parts by producing different mycotoxins, which are toxic to humans and animals. Within the last decade, this fungus has also been described as one of the causes of red root rot or sudden death syndrome in soybean, which causes extensive damage to this crop. This study describes the Agrobacterium tumefaciens-mediated transformation of F. proliferatum as a tool for the disruption of pathogenicity genes. The genetic transformation was performed using two binary vectors (pCAMDsRed and pFAT-GFP) containing the hph (hygromycin B resistance) gene as a selection marker and red and green fluorescence, respectively. The presence of acetosyringone and the use of filter paper or nitrocellulose membrane were evaluated for their effect on the transformation efficiency. A mean processing rate of 94% was obtained with 96 h of co-cultivation only in the presence of acetosyringone and the use of filter paper or nitrocellulose membrane did not affect the transformation process. Hygromycin B resistance and the presence of the hph gene were confirmed by PCR, and fluorescence due to the expression of GFP and DsRed protein was monitored in the transformants. A high rate of mitotic stability (95%) was observed. The efficiency of Agrobacterium-mediated transformation of F. proliferatum allows the technique to be used for random insertional mutagenesis studies and to analyze fungal genes involved in the infection process.

  11. Fungus Infections: Tinea

    MedlinePlus

    ... Share: Yes No, Keep Private Fungus Infections Share | Tinea is the name given to a fungal skin ... Sometime the susceptibility will run in the family. Tinea Pedis (Athlete's foot) This is the most common ...

  12. Fungus Infections: Preventing Recurrence

    MedlinePlus

    ... place for these spores to collect is in shoes. Therefore, after effective treatment, a fungus may recur ... feet clean, cool and dry. Change socks. Wear shoes that "breathe" like leather, rather than plastic. Make ...

  13. Optimizing conditions of a cell-free toxic filtrate stem cutting assay to evaluate soybean genotype responses to Fusarium species that cause sudden death syndrome

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Cell-free toxic culture filtrates from Fusarium virguliforme, the causal fungus of soybean sudden death syndrome (SDS), cause foliar symptoms on soybean stem-cuttings similar to those obtained from root inoculations in whole plants and those observed in production fields. The objectives of this stud...

  14. Registration of five pima cotton germplasm lines (SJ-FR05 - FR09) with improved resistance to fusarium wilt race 4 and good lint yield and fiber quality

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Cotton breeders continue to need alternative sources of cotton breeding lines for improving Fusarium wilt (FOV race 4) resistance in Pima cotton in California. FOV race 4 is a fungus that has impacted cotton yields in the San Joaquin Valley (SJV) for the last 12 years. For this purpose, the Agricult...

  15. Quantification of Fusarium solani f. sp. glycines Isolates in Soybean Roots by Colony-forming Unit Assays and Real-time Quantitative PCR

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Fusarium solani f. sp. glycines (FSG; syn. F. virguliforme Akoi, O’Donnell, Homma & Lattanzi) is a soil-borne fungus that infects soybean roots and causes sudden death syndrome (SDS) a widespread and destructive soybean disease. The goal of this study was to develop and used a real-time quantitative...

  16. Surfactin A production and isoforms characterizations in strains of Bacillus mojavensis for control of a maize pathogen, Fusarium verticillioides

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The endophytic bacterium, Bacillus mojavensis, RRC 101 controls fungal diseases in maize and other plants. The bacterium and its cultural extracts have been shown to be antagonistic to the pathogenic and mycotoxic fungus, Fusarium verticillioides. An antifungal cyclic lipopeptide produced by B. moj...

  17. Enhancement of trichothecene production in Fusarium graminearum by cobalt chloride.

    PubMed

    Tsuyuki, Rie; Yoshinari, Tomoya; Sakamoto, Naoko; Nagasawa, Hiromichi; Sakuda, Shohei

    2011-03-09

    The effects of cobalt chloride on the production of trichothecene and ergosterol in Fusarium graminearum were examined. Incorporation experiments with (13)C-labeled acetate and leucine confirmed that both 3-acetyldeoxynivalenol and ergosterol were biosynthesized via a mevalonate pathway by the fungus, although hydroxymethyl-glutaryl CoA (HMG-CoA) from intact leucine was able to be partially used for ergosterol production. Addition of cobalt chloride at concentrations of 3-30 μM into liquid culture strongly enhanced 3-acetyldeoxynivalenol production by the fungus, whereas the amount of ergosterol and the mycelial weight of the fungus did not change. The mRNA levels of genes encoding trichothecene biosynthetic proteins (TRI4 and TRI6), ergosterol biosynthetic enzymes (ERG3 and ERG25), and enzymes involved in the mevalonate pathway (HMG-CoA synthase (HMGS) and HMG-CoA reductase (HMGR)) were all strongly up-regulated in the presence of cobalt chloride. Precocene II, a specific trichothecene production inhibitor, suppressed the effects of cobalt chloride on Tri4, Tri6, HMGS, and HMGR, but did not affect erg3 and erg25. These results indicate that cobalt chloride is useful for investigating regulatory mechanisms of trichothecene and ergosterol production in F. graminearum.

  18. Different Transcriptional Response to Xanthomonas citri subsp. citri between Kumquat and Sweet Orange with Contrasting Canker Tolerance

    PubMed Central

    Fu, Xing-Zheng; Gong, Xiao-Qing; Zhang, Yue-Xin; Wang, Yin; Liu, Ji-Hong

    2012-01-01

    Citrus canker disease caused by Xanthomonas citri subsp. citri (Xcc) is one of the most devastating biotic stresses affecting the citrus industry. Meiwa kumquat (Fortunella crassifolia) is canker-resistant, while Newhall navel orange (Citrus sinensis Osbeck) is canker-sensitive. To understand the molecular mechanisms underlying the differences in responses to Xcc, transcriptomic profiles of these two genotypes following Xcc attack were compared by using the Affymetrix citrus genome GeneChip. A total of 794 and 1324 differentially expressed genes (DEGs) were identified as canker-responsive genes in Meiwa and Newhall, respectively. Of these, 230 genes were expressed in common between both genotypes, while 564 and 1094 genes were only significantly expressed in either Meiwa or Newhall. Gene ontology (GO) annotation and Singular Enrichment Analysis (SEA) of the DEGs showed that genes related to the cell wall and polysaccharide metabolism were induced for basic defense in both Meiwa and Newhall, such as chitinase, glucanase and thaumatin-like protein. Moreover, apart from inducing basic defense, Meiwa showed specially upregulated expression of several genes involved in the response to biotic stimulus, defense response, and cation binding as comparing with Newhall. And in Newhall, abundant photosynthesis-related genes were significantly down-regulated, which may be in order to ensure the basic defense. This study revealed different molecular responses to canker disease in Meiwa and Newhall, affording insight into the response to canker and providing valuable information for the identification of potential genes for engineering canker tolerance in the future. PMID:22848606

  19. Phylogeography of the Walnut Twig Beetle, Pityophthorus juglandis, the Vector of Thousand Cankers Disease in North American Walnut Trees

    PubMed Central

    Rugman-Jones, Paul F.; Seybold, Steven J.; Graves, Andrew D.; Stouthamer, Richard

    2015-01-01

    Thousand cankers disease (TCD) of walnut trees (Juglans spp.) results from aggressive feeding in the phloem by the walnut twig beetle (WTB), Pityophthorus juglandis, accompanied by inoculation of its galleries with a pathogenic fungus, Geosmithia morbida. In 1960, WTB was only known from four U.S. counties (in Arizona, California, and New Mexico), but the species has now (2014) invaded over 115 counties, representing much of the western USA, and at least six states in the eastern USA. The eastern expansion places TCD in direct proximity to highly valuable (> $500 billion) native timber stands of eastern black walnut, Juglans nigra. Using mitochondrial DNA sequences, from nearly 1100 individuals, we examined variation among 77 samples of WTB populations across its extended range in the USA, revealing high levels of polymorphism and evidence of two divergent lineages. The highest level of genetic diversity for the different lineages was found in the neighboring Madrean Sky Island and Western New Mexico regions, respectively. Despite their proximity, there was little evidence of mixing between these regions, with only a single migrant detected among 179 beetles tested. Indeed, geographic overlap of the two lineages was only common in parts of Colorado and Utah. Just two haplotypes, from the same lineage, predominated over the vast majority of the recently expanded range. Tests for Wolbachia proved negative suggesting it plays no role in "driving" the spread of particular haplotypes, or in maintaining deep levels of intraspecific divergence in WTB. Genotyping of ribosomal RNA corroborated the mitochondrial lineages, but also revealed evidence of hybridization between them. Hybridization was particularly prevalent in the sympatric areas, also apparent in all invaded areas, but absent from the most haplotype-rich area of each mitochondrial lineage. Hypotheses about the specific status of WTB, its recent expansion, and potential evolutionary origins of TCD are discussed

  20. Phylogeography of the walnut twig beetle, Pityophthorus juglandis, the vector of thousand cankers disease in North American walnut trees.

    PubMed

    Rugman-Jones, Paul F; Seybold, Steven J; Graves, Andrew D; Stouthamer, Richard

    2015-01-01

    Thousand cankers disease (TCD) of walnut trees (Juglans spp.) results from aggressive feeding in the phloem by the walnut twig beetle (WTB), Pityophthorus juglandis, accompanied by inoculation of its galleries with a pathogenic fungus, Geosmithia morbida. In 1960, WTB was only known from four U.S. counties (in Arizona, California, and New Mexico), but the species has now (2014) invaded over 115 counties, representing much of the western USA, and at least six states in the eastern USA. The eastern expansion places TCD in direct proximity to highly valuable (> $500 billion) native timber stands of eastern black walnut, Juglans nigra. Using mitochondrial DNA sequences, from nearly 1100 individuals, we examined variation among 77 samples of WTB populations across its extended range in the USA, revealing high levels of polymorphism and evidence of two divergent lineages. The highest level of genetic diversity for the different lineages was found in the neighboring Madrean Sky Island and Western New Mexico regions, respectively. Despite their proximity, there was little evidence of mixing between these regions, with only a single migrant detected among 179 beetles tested. Indeed, geographic overlap of the two lineages was only common in parts of Colorado and Utah. Just two haplotypes, from the same lineage, predominated over the vast majority of the recently expanded range. Tests for Wolbachia proved negative suggesting it plays no role in "driving" the spread of particular haplotypes, or in maintaining deep levels of intraspecific divergence in WTB. Genotyping of ribosomal RNA corroborated the mitochondrial lineages, but also revealed evidence of hybridization between them. Hybridization was particularly prevalent in the sympatric areas, also apparent in all invaded areas, but absent from the most haplotype-rich area of each mitochondrial lineage. Hypotheses about the specific status of WTB, its recent expansion, and potential evolutionary origins of TCD are discussed.

  1. Fusarium subglutinans: A new eumycetoma agent.

    PubMed

    Campos-Macías, Pablo; Arenas-Guzmán, Roberto; Hernández-Hernández, Francisca

    2013-07-09

    Eumycetoma is a chronic subcutaneous mycosis mainly caused by Madurella spp. Fusarium opportunistic infections in humans are often caused by Fusarium solani and Fusarium oxysporum. We report a case of eumycetoma by F. subglutinans, diagnosed by clinical aspect and culture, and confirmed by PCR sequencing. The patient was successfully treated with oral itraconazole. To our knowledge, this is the second report of human infection and the first case of mycetoma by Fusarium subglutinans.

  2. Fusarium subglutinans: A new eumycetoma agent☆

    PubMed Central

    Campos-Macías, Pablo; Arenas-Guzmán, Roberto; Hernández-Hernández, Francisca

    2013-01-01

    Eumycetoma is a chronic subcutaneous mycosis mainly caused by Madurella spp. Fusarium opportunistic infections in humans are often caused by Fusarium solani and Fusarium oxysporum. We report a case of eumycetoma by F. subglutinans, diagnosed by clinical aspect and culture, and confirmed by PCR sequencing. The patient was successfully treated with oral itraconazole. To our knowledge, this is the second report of human infection and the first case of mycetoma by Fusarium subglutinans. PMID:24432236

  3. Vinegar residue compost as a growth substrate enhances cucumber resistance against the Fusarium wilt pathogen Fusarium oxysporum by regulating physiological and biochemical responses.

    PubMed

    Shi, Lu; Du, Nanshan; Yuan, Yinghui; Shu, Sheng; Sun, Jin; Guo, Shirong

    2016-09-01

    Fusarium wilt caused by the fungus Fusarium oxysporum f. sp. cucumerinum (FOC) is the most severe soil-borne disease attacking cucumber. To assess the positive effects of vinegar residue substrate (VRS) on the growth and incidence of Fusarium wilt on cucumber, we determined the cucumber growth parameters, disease severity, defense-related enzyme and pathogenesis-related (PR) protein activities, and stress-related gene expression levels. In in vitro and pot experiments, we demonstrated the following results: (i) the VRS extract exhibited a higher biocontrol activity than that of peat against FOC, and significantly improved the growth inhibition of FOC, with values of 48.3 %; (ii) in response to a FOC challenge, antioxidant enzymes and the key enzymes of phenylpropanoid metabolic activities, as well as the PR protein activities in the roots of cucumber, were significantly increased. Moreover, the activities of these proteins were higher in VRS than in peat; (iii) the expression levels of stress-related genes (including glu, pal, and ethylene receptor) elicited responses to the pathogens inoculated in cucumber leaves; and (iv) the FOC treatment significantly inhibited the growth of cucumber seedlings. Moreover, all of the growth indices of plants grown in VRS were significantly higher than those grown in peat. These results offer a new strategy to control cucumber Fusarium wilt, by upregulating the activity levels of defense-related enzymes and PR proteins and adjusting gene expression levels. They also provide a theoretical basis for VRS applications.

  4. Complete DNA Sequence of Pseudomonas syringae pv. actinidiae, the Causal Agent of Kiwifruit Canker Disease.

    PubMed

    Templeton, Matthew D; Warren, Benjamin A; Andersen, Mark T; Rikkerink, Erik H A; Fineran, Peter C

    2015-09-17

    Pseudomonas syringae pv. actinidiae is the causal agent of bacterial canker of kiwifruit, a disease that has rapidly spread worldwide. We have fully sequenced and assembled the chromosomal and plasmid DNA from P. syringae pv. actinidiae ICMP 18884 using the PacBio RS II platform.

  5. Rapid screening for citrus canker resistance employing pattern-triggered immunity (PTI) responses

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Citrus canker, caused by the bacterial pathogen Xanthomonas citri ssp. citri (Xcc), has been attributed to millions of dollars in loss or damage to commercial citrus crops in subtropical production areas of the world. Since identification of resistant plants is one of the most effective methods of d...

  6. Optimal strategies for the eradication of Asiatic citrus canker in heterogeneous host landscapes

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The eradication of non-native plant pathogens is a key challenge in plant disease epidemiology. Asiatic citrus canker is an economically significant disease of citrus caused by the bacterial plant pathogen Xanthomonas citri subsp. citri. The pathogen is a major exotic disease problem in many citru...

  7. Wind speed and wind-associated leaf injury affect severity of citrus canker on Swingle citrumelo

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Citrus canker (caused by the bacterial pathogen Xanthomonas citri subsp. citri, Xcc) can cause severe damage to citrus. It is endemic in Florida, and occurs in other citrus growing regions. The bacterium is dispersed predominantly in rain splash. To simulate dispersal in splash, and to investigate t...

  8. Commercial postharvest practices used to handle fresh citrus fruit with canker symptoms

    Technology Transfer Automated Retrieval System (TEKTRAN)

    To assist in developing best postharvest practices for handling fruit with canker lesions, a survey was distributed in summers of 2008 and 2009 to better understand current practices. Approximately 60% of the surveys were returned each year representing about 55% of total fresh fruit shipments. As e...

  9. Evaluation of resistance to asiatic citrus canker among selections of pera sweet orange (Citrus sinensis)

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Asiatic citrus canker (ACC, caused by the bacterium Xanthomonas citri subsp. citri) is a destructive disease of citrus in Brazil and in several other citrus-producing countries. ACC management is problematic, and bactericides such as copper can be reasonably efficacious but do not completely control...

  10. Phomopsis Stem Canker: A Reemerging Threat to Sunflower (Helianthus annuus) in the United States.

    PubMed

    Mathew, Febina M; Alananbeh, Kholoud M; Jordahl, James G; Meyer, Scott M; Castlebury, Lisa A; Gulya, Thomas J; Markell, Samuel G

    2015-07-01

    Phomopsis stem canker causes yield reductions on sunflower (Helianthus annuus L.) on several continents, including Australia, Europe, and North America. In the United States, Phomopsis stem canker incidence has increased 16-fold in the Northern Great Plains between 2001 and 2012. Although Diaporthe helianthi was assumed to be the sole causal agent in the United States, a newly described species, D. gulyae, was found to be the primary cause of Phomopsis stem canker in Australia. To determine the identity of Diaporthe spp. causing Phomopsis stem canker in the Northern Great Plains, 275 infected stems were collected between 2010 and 2012. Phylogenetic analyses of sequences of the ribosomal DNA internal transcribed spacer region, elongation factor subunit 1-α, and actin gene regions of representative isolates, in comparison with those of type specimens, confirmed two species (D. helianthi and D. gulyae) in the United States. Differences in aggressiveness between the two species were determined using the stem-wound method in the greenhouse; overall, D. helianthi and D. gulyae did not vary significantly (P≤0.05) in their aggressiveness at 10 and 14 days after inoculation. These findings indicate that both Diaporthe spp. have emerged as sunflower pathogens in the United States, and have implications on the management of this disease.

  11. New canker disease of Incense-cedar in Oregon caused by Phaeobotryon cupressi.

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Incense-cedar (Calocedrus decurrens) is a native tree occurring in Oregon and California. Since the early 2000’s, a new canker disease has been observed with increasing frequency on ornamental and windbreak trees planted in the Willamette Valley of Oregon. Symptoms appear as dead, flagging, small-di...

  12. Resistance evaluation of Pera (Citrus sinensis) genotypes to citrus canker in greenhouse conditions

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Citrus canker, caused by the bacterium Xanthomonas citri subsp. citri results in serious yield losses and phytoregulation penalties. The use of resistant genotypes is recognized as an important tool to facilitate control of the pathogen. Studies have show that artificial inoculation results in typic...

  13. Exacerbation of citrus canker by citrus leafminer, Phyllocnistis citrella in Florida

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Citrus canker (caused by Xanthomonas citri subsp. citri, Xcc) is an important bacterial disease of citrus that is spread naturally by rain and wind. Damage to citrus leaves by the citrus leafminer (CLM) , Phyllocnistis citrella Stainton (Lepidoptera: Gracillariidae), has been shown to promote infect...

  14. Canker and twig dieback of blueberry caused by Pestalotiopsis spp. and a Truncatella sp. in Chile

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Blueberry (Vaccinium spp.) has great economic importance in Chile, currently with about 8,500 ha being cultivated. Recently, the presence of canker and dieback symptoms has been observed along the productive blueberry zone of Chile extending from the V Region (32º49´ South lat.) in the north to the ...

  15. First report of Phaeobotryon cupressi causing canker of Calocedrus decurrens in Oregon.

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Since the early 2000’s a canker disease has been noticed with increasing frequency on landscape specimens of native incense cedar (Calocedrus decurrens) planted throughout the Willamette Valley (from Portland south to Eugene) in western Oregon. Symptoms initially appear as dead and flagging small-di...

  16. Overexpression of a Modified Plant Thionin Enhances Disease Resistance to Citrus Canker and Huanglongbing (HLB).

    PubMed

    Hao, Guixia; Stover, Ed; Gupta, Goutam

    2016-01-01

    Huanglongbing (HLB or citrus greening disease) caused by Candidatus Liberibacter asiaticus (Las) is a great threat to the US citrus industry. There are no proven strategies to eliminate HLB disease and no cultivar has been identified with strong HLB resistance. Citrus canker is also an economically important disease associated with a bacterial pathogen (Xanthomonas citri). In this study, we characterized endogenous citrus thionins and investigated their expression in different citrus tissues. Since no HLB-resistant citrus cultivars have been identified, we attempted to develop citrus resistant to both HLB and citrus canker through overexpression of a modified plant thionin. To improve effectiveness for disease resistance, we modified and synthesized the sequence encoding a plant thionin and cloned into the binary vector pBinPlus/ARS. The construct was then introduced into Agrobacterium strain EHA105 for citrus transformation. Transgenic Carrizo plants expressing the modified plant thionin were generated by Agrobacterium-mediated transformation. Successful transformation and transgene gene expression was confirmed by molecular analysis. Transgenic Carrizo plants expressing the modified thionin gene were challenged with X. citri 3213 at a range of concentrations, and a significant reduction in canker symptoms and a decrease in bacterial growth were demonstrated compared to nontransgenic plants. Furthermore, the transgenic citrus plants were challenged with HLB via graft inoculation. Our results showed significant Las titer reduction in roots of transgenic Carrizo compared with control plants and reduced scion Las titer 12 months after graft inoculation. These data provide promise for engineering citrus disease resistance against HLB and canker.

  17. Production of transgenic citrus resistant to citrus canker and Huanglongbing diseases

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Huanglongbing (HLB or citrus greening disease) caused by Candidatus Liberibacter asiaticus (Las) is a great threat to the U.S. citrus industry. There are no proven strategies to eliminate HLB disease and no cultivars identified with strong HLB resistance. Citrus canker is also an economically import...

  18. Overexpression of a modified plant thionin enhances disease resistance to citrus canker and Huanglongbing (HLB)

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Huanglongbing (HLB or citrus greening disease) caused by Candidatus Liberibacter asiaticus (Las) is a great threat to the United States citrus industry. There are no proven strategies to eliminate HLB disease and no cultivar has been identified with strong HLB resistance. Citrus canker is also an ec...

  19. Fusarium temperatum and Fusarium subglutinans isolated from maize in Argentina.

    PubMed

    Fumero, María Verónica; Reynoso, María Marta; Chulze, Sofía

    2015-04-16

    Fusarium temperatum and Fusarium subglutinans isolated from the Northwest region (NOA region) of Argentina were characterized using a polyphasic approach based on morphological, biological and molecular markers. Some interfertility between the species was observed. The phylogenetic analysis showed that the two species represented two clades strongly supported by bootstrap values. The toxigenic profile of the strains was also determined. F. temperatum strains were fusaproliferin and beauvericin producers, and only some strains were fumonisin B1 producers. All F. subglutinans strains produced fusaproliferin but none produced beauvericin, indicating a potential toxicological risk from maize harvested in the NOA region of Argentina. This study provides new information about F. temperatum isolated from maize in Argentina.

  20. Hyperspectral reflectance imaging for detecting citrus canker based on dual-band ratio image classification method

    NASA Astrophysics Data System (ADS)

    Li, Jiangbo; Rao, Xiuqin; Guo, Junxian; Ying, Yibin

    2010-10-01

    Citrus are one of the major fruit produced in China. Most of this production is exported to Europe for fresh consumption, where consumers increasingly demand best quality. Citrus canker is one of the most devastating diseases that threaten peel of most commercial citrus varieties. The aim of this research was to investigate the potential of using hyperspectral imaging technique for detecting canker lesions on citrus fruit. Navel oranges with cankerous, normal and various common diseased skin conditions including wind scar, thrips scarring, scale insect, dehiscent fruit, phytotoxicity, heterochromatic stripe, and insect damage were studied. The imaging system (400-1000 nm) was established to acquire reflectance images from samples. Region of interest (ROI) spectral feature of various diseased peel areas was analyzed and characteristic wavebands (630, 685, and 720 nm) were extracted. The dual-band reflectance ratio (such as Q720/685) algorithm was performed on the hyperspectral images of navel oranges for differentiating canker from normal fruit skin and other surface diseases. The overall classification success rate was 96.84% regardless of the presence of other confounding diseases. The presented processing approach overcame the presence of stem/navel on navel oranges that typically has been a problematic source for false positives in the detection of defects. Because of the limited sample size, delineation of an optimal detection scheme is beyond the scope of the current study. However, the results showed that two-band ratio (Q685/630) along with the use of a simple threshold value segmentation method for discriminating canker on navel oranges from other peel diseases may be feasible.

  1. Fusarochromanone production by Fusarium isolates.

    PubMed Central

    Wu, W D; Nelson, P E; Cook, M E; Smalley, E B

    1990-01-01

    Sixty two Fusarium isolates representing nine species from many parts of the world were screened for fusarochromanone production. A simplified method for the detection of fusarochromanone in culture filtrates or grain cultures was used. Under UV irradiation (364 nm) the chloroform phase from fusarochromanone-positive culture extracts fluoresced a characteristic bright blue color. Results were confirmed by thin-layer-chromatography comparison with pure fusarochromanone standards. Detection was possible in cultures as young as 1 week old. Biosynthesis of fusarochromanone was rare in Fusarium spp. and was only detected in three isolates of Fusarium equiseti, namely R-4482 (barley [Federal Republic of Germany]), R-6137 (barley [Alaska]), and R-8508 (potato [Denmark]), among all the isolates tested from various geographic sources. Images PMID:2285312

  2. Fusion proteins comprising a Fusarium-specific antibody linked to antifungal peptides protect plants against a fungal pathogen.

    PubMed

    Peschen, Dieter; Li, He-Ping; Fischer, Rainer; Kreuzaler, Fritz; Liao, Yu-Cai

    2004-06-01

    In planta expression of recombinant antibodies recognizing pathogen-specific antigens has been proposed as a strategy for crop protection. We report the expression of fusion proteins comprising a Fusarium-specific recombinant antibody linked to one of three antifungal peptides (AFPs) as a method for protecting plants against fungal diseases. A chicken-derived single-chain antibody specific to antigens displayed on the Fusarium cell surface was isolated from a pooled immunocompetent phage display library. This recombinant antibody inhibited fungal growth in vitro when fused to any of the three AFPs. Expression of the fusion proteins in transgenic Arabidopsis thaliana plants conferred high levels of protection against Fusarium oxysporum f.sp. matthiolae, whereas plants expressing either the fungus-specific antibody or AFPs alone exhibited only moderate resistance. Our results demonstrate that antibody fusion proteins may be used as effective and versatile tools for the protection of crop plants against fungal infection.

  3. Deoxynivalenol: A Major Player in the Multifaceted Response of Fusarium to Its Environment

    PubMed Central

    Audenaert, Kris; Vanheule, Adriaan; Höfte, Monica; Haesaert, Geert

    2013-01-01

    The mycotoxin deoxynivalenol (DON), produced by several Fusarium spp., acts as a virulence factor and is essential for symptom development after initial wheat infection. Accumulating evidence shows that the production of this secondary metabolite can be triggered by diverse environmental and cellular signals, implying that it might have additional roles during the life cycle of the fungus. Here, we review data that position DON in the saprophytic fitness of Fusarium, in defense and in the primary C and N metabolism of the plant and the fungus. We combine the available information in speculative models on the role of DON throughout the interaction with the host, providing working hypotheses that await experimental validation. We also highlight the possible impact of control measures in the field on DON production and summarize the influence of abiotic factors during processing and storage of food and feed matrices. Altogether, we can conclude that DON is a very important compound for Fusarium to cope with a changing environment and to assure its growth, survival, and production of toxic metabolites in diverse situations. PMID:24451843

  4. Identification and regulation of fusA, the polyketide synthase gene responsible for fusarin production in Fusarium fujikuroi.

    PubMed

    Díaz-Sánchez, Violeta; Avalos, Javier; Limón, M Carmen

    2012-10-01

    Fusarins are a class of mycotoxins of the polyketide family produced by different Fusarium species, including the gibberellin-producing fungus Fusarium fujikuroi. Based on sequence comparisons between polyketide synthase (PKS) enzymes for fusarin production in other Fusarium strains, we have identified the F. fujikuroi orthologue, called fusA. The participation of fusA in fusarin biosynthesis was demonstrated by targeted mutagenesis. Fusarin production is transiently stimulated by nitrogen availability in this fungus, a regulation paralleled by the fusA mRNA levels in the cell. Illumination of the cultures results in a reduction of the fusarin content, an effect partially explained by a high sensitivity of these compounds to light. Mutants of the fusA gene exhibit no external phenotypic alterations, including morphology and conidiation, except for a lack of the characteristic yellow and/or orange pigmentation of fusarins. Moreover, the fusA mutants are less efficient than the wild type at degrading cellophane on agar cultures, a trait associated with pathogenesis functions in Fusarium oxysporum. The fusA mutants, however, are not affected in their capacities to grow on plant tissues.

  5. Fusarium graminearum forms mycotoxin producing infection structures on wheat

    PubMed Central

    2011-01-01

    Background The mycotoxin producing fungal pathogen Fusarium graminearum is the causal agent of Fusarium head blight (FHB) of small grain cereals in fields worldwide. Although F. graminearum is highly investigated by means of molecular genetics, detailed studies about hyphal development during initial infection stages are rare. In addition, the role of mycotoxins during initial infection stages of FHB is still unknown. Therefore, we investigated the infection strategy of the fungus on different floral organs of wheat (Triticum aestivum L.) under real time conditions by constitutive expression of the dsRed reporter gene in a TRI5prom::GFP mutant. Additionally, trichothecene induction during infection was visualised with a green fluorescent protein (GFP) coupled TRI5 promoter. A tissue specific infection pattern and TRI5 induction were tested by using different floral organs of wheat. Through combination of bioimaging and electron microscopy infection structures were identified and characterised. In addition, the role of trichothecene production for initial infection was elucidated by a ΔTRI5-GFP reporter strain. Results The present investigation demonstrates the formation of foot structures and compound appressoria by F. graminearum. All infection structures developed from epiphytic runner hyphae. Compound appressoria including lobate appressoria and infection cushions were observed on inoculated caryopses, paleas, lemmas, and glumes of susceptible and resistant wheat cultivars. A specific trichothecene induction in infection structures was demonstrated by different imaging techniques. Interestingly, a ΔTRI5-GFP mutant formed the same infection structures and exhibited a similar symptom development compared to the wild type and the TRI5prom::GFP mutant. Conclusions The different specialised infection structures of F. graminearum on wheat florets, as described in this study, indicate that the penetration strategy of this fungus is far more complex than postulated to

  6. Cytospora species associated with walnut canker disease in China, with description of a new species C. gigalocus.

    PubMed

    Fan, Xinlei; Hyde, Kevin D; Liu, Min; Liang, Yingmei; Tian, Chengming

    2015-05-01

    Cytospora species associated with canker disease are presently difficult to identify because of lack of ex-types cultures with molecular data, few distinguishable characters, and only Internal transcribed spacer (ITS) sequence data is available for most Cytospora strains in GenBank. We report on Cytospora species from the walnut tree in China. Collections were subjected to morphological and phylogenetic study. The relatedness of species associated with walnut canker were established using combined ITS, nrLSU, β-tubulin, and actin gene sequence data. Cytospora atrocirrhata, Cytospora chrysosperma, Cytospora sacculus, and a new species, Cytospora gigalocus, were identified causing canker disease of walnut. Cytospora gigalocus is formally described and compared with most similar species. Cytospora chrysosperma and C. sacculus have previously been recorded from walnut, whereas C. atrocirrhata is reported as associated with walnut canker for the first time. This is the first study that has established the Cytospora species causing walnut canker in China using a multi-phasic approach. All species are recorded as being associated with walnut canker disease in China for the first time.

  7. Fusarium foetens, a new species pathogenic to begonia elatior hybrids (Begonia x hiemalis) and the sister taxon of the Fusarium oxysporum species complex.

    PubMed

    Schroers, H-J; Baayen, R P; Meffert, J P; de Gruyter, J; Hooftman, M; O'Donnell, K

    2004-01-01

    A new disease recently was discovered in begonia elatior hybrid (Begonia × hiemalis) nurseries in The Netherlands. Diseased plants showed a combination of basal rot, vein yellowing and wilting and the base of collapsing plants was covered by unusually large masses of Fusarium macroconidia. A species of Fusarium was isolated consistently from the discolored veins of leaves and stems. It differed morphologically from F. begoniae, a known agent of begonia flower, leaf and stem blight. The Fusarium species resembled members of the F. oxysporum species complex in producing short monophialides on the aerial mycelium and abundant chlamydospores. Other phenotypic characters such as polyphialides formed occasionally in at least some strains, relatively long monophialides intermingled with the short monophialides formed on the aerial mycelium, distinct sporodochial conidiomata, and distinct pungent colony odor distinguished it from the F. oxysporum species complex. Phylogenetic analyses of partial sequences of the mitochondrial small subunit of the ribosomal DNA (mtSSU rDNA), nuclear translation elongation factor 1α (EF-1α) and β-tubulin gene exons and introns indicate that the Fusarium species represents a sister group of the F. oxysporum species complex. Begonia × hiemalis cultivars Bazan, Bellona and Netja Dark proved to be highly susceptible to the new species. Inoculated plants developed tracheomycosis within 4 wk, and most died within 8 wk. The new taxon was not pathogenic to Euphorbia pulcherrima, Impatiens walleriana and Saintpaulia ionantha that commonly are grown in nurseries along with B. × hiemalis. Inoculated plants of Cyclamen persicum did not develop the disease but had discolored vessels from which the inoculated fungus was isolated. Given that the newly discovered begonia pathogen is distinct in pathogenicity, morphology and phylogeny from other fusaria, it is described here as a new species, Fusarium foetens.

  8. Draft Genome Sequences of Pectobacterium carotovorum subsp. actinidiae ICMP 19971 and ICMP 19972, Two Strains Isolated from Actinidia chinensis with Symptoms of Summer Canker in South Korea.

    PubMed

    Visnovsky, Sandra B; Panda, Preetinanda; Taylor, Robert; Pitman, Andrew R

    2017-04-06

    Pectobacterium carotovorum subsp. actinidiae is the causal agent of summer canker in kiwifruit plants in South Korea. We report here the draft genome sequences of two P. carotovorum subsp. actinidiae strains, ICMP 19971 and ICMP 19972, which were originally isolated from Actinidia chinensis with symptoms of summer canker. These genome sequences will aid in the identification of genetic traits associated with their unusual capacity to cause canker and help understanding of the threat these exotic enterobacteria pose to the New Zealand kiwifruit industry.

  9. First Report and Characterization of Pestalotiopsis ellipsospora Causing Canker on Acanthopanax divaricatus

    PubMed Central

    Yun, Yeo Hong; Ahn, Geum Ran

    2015-01-01

    Acanthopanax divaricatus, a member of the Araliaceae family, has been used as an invigorant in traditional Korean medicine. During disease monitoring, a stem with small, irregular, brown lesions was sampled at a farm in Cheonan in 2011. The symptoms seen were sunken cankers and reddish-brown needles on the infected twig. The isolated fungal colonies were whitish, having crenated edges and aerial mycelium on the surface, and with black gregarious fruiting bodies. The reverse plate was creamy white. Conidia were 17~22 × 3.5~4.2 µm, fusiform, 4-septate, and straight to slightly curved. The nucleotide sequence of the partial translation elongation factor 1 alpha gene of the fungal isolate, shares 99% sequence identity with that of known Pestalotiopsis ellipsospora. Based on the results of the morphological and molecular analyses, the fungal isolate was identified as P. ellipsospora. In Korea, this is the first report of canker on A. divaricatus. PMID:26539058

  10. Challenges in Fusarium, a Trans-Kingdom Pathogen.

    PubMed

    van Diepeningen, Anne D; de Hoog, G Sybren

    2016-04-01

    Fusarium species are emerging human pathogens, next to being plant pathogens. Problems with Fusarium are in their diagnostics and in their difficult treatment, but also in what are actual Fusarium species or rather Fusarium-like species. In this issue Guevara-Suarez et al. (Mycopathologia. doi: 10.1007/s11046-016-9983-9 , 2016) characterized 89 isolates of Fusarium from Colombia showing especially lineages within the Fusarium solani and oxysporum species complexes to be responsible for onychomycosis.

  11. Overexpression of a Modified Plant Thionin Enhances Disease Resistance to Citrus Canker and Huanglongbing (HLB)

    PubMed Central

    Hao, Guixia; Stover, Ed; Gupta, Goutam

    2016-01-01

    Huanglongbing (HLB or citrus greening disease) caused by Candidatus Liberibacter asiaticus (Las) is a great threat to the US citrus industry. There are no proven strategies to eliminate HLB disease and no cultivar has been identified with strong HLB resistance. Citrus canker is also an economically important disease associated with a bacterial pathogen (Xanthomonas citri). In this study, we characterized endogenous citrus thionins and investigated their expression in different citrus tissues. Since no HLB-resistant citrus cultivars have been identified, we attempted to develop citrus resistant to both HLB and citrus canker through overexpression of a modified plant thionin. To improve effectiveness for disease resistance, we modified and synthesized the sequence encoding a plant thionin and cloned into the binary vector pBinPlus/ARS. The construct was then introduced into Agrobacterium strain EHA105 for citrus transformation. Transgenic Carrizo plants expressing the modified plant thionin were generated by Agrobacterium-mediated transformation. Successful transformation and transgene gene expression was confirmed by molecular analysis. Transgenic Carrizo plants expressing the modified thionin gene were challenged with X. citri 3213 at a range of concentrations, and a significant reduction in canker symptoms and a decrease in bacterial growth were demonstrated compared to nontransgenic plants. Furthermore, the transgenic citrus plants were challenged with HLB via graft inoculation. Our results showed significant Las titer reduction in roots of transgenic Carrizo compared with control plants and reduced scion Las titer 12 months after graft inoculation. These data provide promise for engineering citrus disease resistance against HLB and canker. PMID:27499757

  12. In vitro generation of somaclonal variant plants of sugarcane for tolerance to Fusarium sacchari.

    PubMed

    Mahlanza, Tendekai; Rutherford, R Stuart; Snyman, Sandy J; Watt, M Paula

    2013-02-01

    KEY MESSAGE : A combination of in vitro culture and mutagenesis using ethyl methanesulfonate (EMS) followed by culture filtrate-mediated selection produced variant sugarcane plants tolerant and resistant to Fusarium sacchari. Eldana saccharina is a destructive pest of the sugarcane crop in South Africa. Fusarium sacchari PNG40 (a fungal strain harmful to E. saccharina) has the potential to be an endophytic biological control agent of the stalk borer. However, the fungus causes Fusarium stalk rot in sugarcane. In the current study, sugarcane plants tolerant and resistant to F. sacchari PNG40 were produced by exposing embryogenic calli to the chemical mutagen ethyl methanesulfonate (EMS), followed by in vitro selection during somatic embryogenesis and plantlet regeneration on media containing F. sacchari culture filtrates (CF). The incorporation of 100 ppm CF in the culture media at the embryo maturation stage, at germination, or at both, resulted in callus necrosis and consequent reduced plantlet yield. Subsequent trimming of the roots of regenerated plants and their exposure to 1,500 ppm CF served as a further selection treatment. Plants produced from EMS-treated calli displayed improved root re-growth in the presence of CF pressure compared with those from non-treated calli. The tolerance of CF-selected plants was confirmed in greenhouse tests by inoculation with F. sacchari PNG40, re-isolation of Fusarium spp. from undamaged tissue of asymptomatic plants and establishment of the identity of fungal isolates as PNG40 using molecular analysis. The restriction of PNG40 presence to the inoculation lesion in some plants suggested their resistance to the fungus. Genotypes exhibiting symptomless endophytic colonization by PNG40 were identified and will be utilised for testing biological control strategies against E. saccharina.

  13. Biofilm formation, epiphytic fitness, and canker development in Xanthomonas axonopodis pv. citri.

    PubMed

    Rigano, Luciano A; Siciliano, Florencia; Enrique, Ramón; Sendín, Lorena; Filippone, Paula; Torres, Pablo S; Qüesta, Julia; Dow, J Maxwell; Castagnaro, Atilio P; Vojnov, Adrián A; Marano, María Rosa

    2007-10-01

    The phytopathogenic bacterium Xanthomonas axonopodis pv. citri is responsible for the canker disease affecting citrus plants throughout the world. Here, we have evaluated the role of bacterial attachment and biofilm formation in leaf colonization during canker development on lemon leaves. Crystal violet staining and confocal laser scanning microscopy analysis of X. axonopodis pv. citri strains expressing the green fluorescent protein were used to evaluate attachment and biofilm formation on abiotic and biotic (leaf) surfaces. Wild-type X. axonopodis pv. citri attached to and formed a complex, structured biofilm on glass in minimal medium containing glucose. Similar attachment and structured biofilm formation also were seen on lemon leaves. An X. axonopodis pv. citri gumB mutant strain, defective in production of the extracellular polysaccharide xanthan, did not form a structured biofilm on either abiotic or biotic surfaces. In addition, the X. axonopodis pv. citri gumB showed reduced growth and survival on leaf surfaces and reduced disease symptoms. These findings suggest an important role for formation of biofilms in the epiphytic survival of X. axonopodis pv. citri prior to development of canker disease.

  14. Rapid screening for citrus canker resistance employing pathogen-associated molecular pattern-triggered immunity responses

    PubMed Central

    Pitino, Marco; Armstrong, Cheryl M; Duan, Yongping

    2015-01-01

    Citrus canker, caused by the bacterial pathogen Xanthomonas citri ssp. citri (Xcc), has been attributed to millions of dollars in loss or damage to commercial citrus crops in subtropical production areas of the world. Since identification of resistant plants is one of the most effective methods of disease management, the ability to screen for resistant seedlings plays a key role in the production of a long-term solution to canker. Here, an inverse correlation between reactive oxygen species (ROS) production by the plant and the ability of Xcc to grow and form lesions on infected plants is reported. Based on this information, a novel screening method that can rapidly identify citrus seedlings that are less susceptible to early infection by Xcc was devised by measuring ROS accumulation triggered by a 22-amino acid sequence of the conserved N-terminal part of flagellin (flg22) from X. citri ssp. citri (Xcc-flg22). In addition to limiting disease symptoms, ROS production was also correlated with the expression of basal defense-related genes such as the pattern recognition receptors LRR8 and FLS2, the leucine-rich repeat receptor-like protein RLP12, and the defense-related gene PR1, indicating an important role for pathogen-associated molecular pattern-triggered immunity (PTI) in determining resistance to citrus canker. Moreover, the differential expression patterns observed amongst the citrus seedlings demonstrated the existence of genetic variations in the PTI response among citrus species/varieties. PMID:26504581

  15. Microbial transformation of the diterpene 7-epi-foliol by Fusarium fujikuroi.

    PubMed

    Fraga, Braulio M; Bressa, Carlo; González, Pedro; Guillermo, Ricardo

    2014-08-01

    The incubation of 3alpha,7alpha,18-trihydroxy-ent-kaur-16-ene (7-epi-foliol) with the fungus Fusarium fujikuroi gave 3alpha,7alpha,18-trihydroxy-ent-kaur-16-en-18-al as the sole product. The biotransformation of other 7alpha- or 7beta-hydroxy derivatives had led to the oxidation of C-19, which is a main step in the biosynthesis of gibberellins and kaurenolides. Now, the presence of the 3alpha-hydroxyl impedes that oxidation, which is directed to the adjacent C-18 hydroxymethyl forming the corresponding aldehyde.

  16. Analysis of carbohydrates in Fusarium verticillioides using size-exclusion HPLC – DRI and direct analysis in real time ionization – time-of-flight – mass spectrometry (DART-MS)

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Direct analysis in real time ionization – time-of-flight – mass spectrometry (DART-MS) and size-exclusion HPLC – DRI are used, respectively, to qualitatively and quantitatively determine the carbohydrates extracted from the corn rot fungus Fusarium verticillioides. In situ permethylation in the DART...

  17. Isolation screening and characterisation of local beneficial rhizobacteria based upon their ability to suppress the growth of Fusarium oxysporum f. sp. radicis-lycopersici and tomato foot and root rot

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Tomato crown and root rot or tomato foot and root rot (TFRR) is caused by the phytopathogenic fungus Fusarium oxysporum f. sp. radicis-lycopersici (Forl). The disease occurs in both greenhouse and outdoor tomato cultivations and cannot be treated efficiently with the existing fungicides. We conducte...

  18. The Fusarium Graminearum Genome Reveals a Link Between Localized Polymorphism and Pathogen Specialization

    SciTech Connect

    Cuomo, Christina A.; Guldener, Ulrich; Xu, Jin Rong; Trail, Frances; Turgeon, Barbara G.; Di Pietro, Antonio; Walton, Johnathan D.; Ma, Li Jun; Baker, Scott E.; Rep, Martijn; Adam, Gerhard; Antoniw, John; Baldwin, Thomas; Calvo, Sarah; Chang, Yueh Long; DeCaprio, David; Gale, Liane R.; Gnerre, Sante; Goswami, Rubella S.; Hammond-Kossack, Kim; Harris, Linda J.; Hilburn, Karen; Kennell, John C.; Kroken, Scott; Magnuson, Jon K.; Mannhaupt, Gertrud; Mauceli, Evan; Mewes, Hans Werner; Mitterbauer, Rudolf; Muehlbauer, Gary; Munsterkotter, Martin; Nelson, David; O'Donnell, Kerry; Ouellet, Therese; Qi, Weihong; Quesneville, Hadi; Roncero, M. Isabel; Seong, Kye Yong; Tetko, Igor V.; Urban, Martin; Waalwijk, Cees; Ward, Todd J.; Yao, Jiqiang; Birren, Bruce W.; Kistler, H. Corby

    2007-09-07

    We sequenced and annotated the genome of the filamentous fungus Fusarium graminearum, a major pathogen of cultivated cereals. Very few repetitive sequences were detected, and the process of repeat-induced point mutation, in which duplicated sequences are subject to extensive mutation, may partially account for the reduced repeat content and apparent low number of paralogous (ancestrally duplicated) genes. A second strain of F. graminearum contained more than 10,000 single-nucleotide polymorphisms, which were frequently located near telomeres and within other discrete chromosomal segments. Many highly polymorphic regions contained sets of genes implicated in plant-fungus interactions and were unusually divergent, with higher rates of recombination. These regions of genome innovation may result from selection due to interactions of F. graminearum with its plant hosts.

  19. Bioconversion of olive-mill dry residue by Fusarium lateritium and subsequent impact on its phytotoxicity.

    PubMed

    Sampedro, I; D'Annibale, A; Ocampo, J A; Stazi, S R; García-Romera, I

    2005-09-01

    The present study investigated the ability of the non-pathogenic fungus Fusarium lateritium to either degrade or modify aromatic substances in olive-mill dry residue (DOR) and to reduce its phytotoxicity. The 80% reduction of ethylacetate extractable phenols in DOR colonized by the fungus for 20 weeks appeared to be due to polymerization reactions of phenol molecules as suggested by mass-balance ultrafiltration and size-exclusion chromatography experiments. Several lignin-modifying oxidases, including laccase, Mn-peroxidase and Mn-inhibited peroxidase were detected in F. lateritium solid-state cultures. Tests performed with tomato seedlings in soils containing 6% (w/w) sterilized non-inoculated DOR showed that the waste was highly phytotoxic. By contract, F. lateritium growth on DOR for 20 weeks led to a complete removal of the waste toxicity and to a higher shoot dry weight of tomato plants than that obtained in the absence of DOR.

  20. [Peptide-containing fraction from a culture medium of Fusarium sambucinum: composition and biological effects].

    PubMed

    Bogdanov, V V; Fatkulina, É F; Berezin, B B; Il'ina, A P; Iamskova, V P; Iamskov, I A

    2014-01-01

    The culture fluid of the fungus Fusarium sambucinum was investigated for the presence of new peptide-containing bioregulators, previously identified in various mammalian and plant tissues. A fraction containing peptides with molecular weights from 1000 to 2000 Da, which exhibited specific membranotropic activity and a number of physical and chemical properties characteristic of this group of bioregulators, was obtained. The effects of this fraction on the model roller organotypic cultivation of liver tissue of the Pleurodeles waltl newt in vitro were investigated for the first time. This fraction caused the additional activation of pigmented liver cells of newt (analogues to Kupffer cells of the liver of mammals) and provided the maintenance of cell-cell adhesive interactions in tissues. The results show that a new group of peptide bioregulators was present in the culture medium of the fungus F. sambucinum.

  1. The Nuclear Protein Sge1 of Fusarium oxysporum Is Required for Parasitic Growth

    PubMed Central

    Reijnen, Linda; Manders, Erik M. M.; Boas, Sonja; Olivain, Chantal; Alabouvette, Claude; Rep, Martijn

    2009-01-01

    Dimorphism or morphogenic conversion is exploited by several pathogenic fungi and is required for tissue invasion and/or survival in the host. We have identified a homolog of a master regulator of this morphological switch in the plant pathogenic fungus Fusarium oxysporum f. sp. lycopersici. This non-dimorphic fungus causes vascular wilt disease in tomato by penetrating the plant roots and colonizing the vascular tissue. Gene knock-out and complementation studies established that the gene for this putative regulator, SGE1 (SIX Gene Expression 1), is essential for pathogenicity. In addition, microscopic analysis using fluorescent proteins revealed that Sge1 is localized in the nucleus, is not required for root colonization and penetration, but is required for parasitic growth. Furthermore, Sge1 is required for expression of genes encoding effectors that are secreted during infection. We propose that Sge1 is required in F. oxysporum and other non-dimorphic (plant) pathogenic fungi for parasitic growth. PMID:19851506

  2. Proteomic analysis of conidia germination in Fusarium oxysporum f. sp. cubense tropical race 4 reveals new targets in ergosterol biosynthesis pathway for controlling Fusarium wilt of banana.

    PubMed

    Deng, Gui-Ming; Yang, Qiao-Song; He, Wei-Di; Li, Chun-Yu; Yang, Jing; Zuo, Cun-Wu; Gao, Jie; Sheng, Ou; Lu, Shao-Yun; Zhang, Sheng; Yi, Gan-Jun

    2015-09-01

    Conidial germination is a crucial step of the soilborne fungus Fusarium oxysporum f. sp. cubense tropical race 4 (Foc TR4), a most important lethal disease of banana. In this study, a total of 3659 proteins were identified by isobaric tags for relative and absolute quantitation (iTRAQ)-based comparative proteomic approach, of which 1009 were differentially expressed during conidial germination of the fungus at 0, 3, 7, and 11 h. Functional classification and bioinformatics analysis revealed that the majority of the differentially expressed proteins are involved in six metabolic pathways. Particularly, all differential proteins involved in the ergosterol biosynthesis pathway were significantly upregulated, indicating the importance of the ergosterol biosynthesis pathway to the conidial germination of Foc TR4. Quantitative RT-PCR, western blotting, and in vitro growth inhibition assay by several categories of fungicides on the Foc TR4 were used to validate the proteomics results. Four enzymes, C-24 sterol methyltransferase (ERG6), cytochrome P450 lanosterol C-14α-demethylase (EGR11), hydroxymethylglutaryl-CoA synthase (ERG13), and C-4 sterol methyl oxidase (ERG25), in the ergosterol biosynthesis pathway were identified and verified, and they hold great promise as new targets for effective inhibition of Foc TR4 early growth in controlling Fusarium wilt of banana. To the best of our knowledge, this report represents the first comprehensive study on proteomics profiling of conidia germination in Foc TR4. It provides new insights into a better understanding of the developmental processes of Foc TR4 spores. More importantly, by host plant-induced gene silencing (HIGS) technology, the new targets reported in this work allow us to develop novel transgenic banana leading to high protection from Fusarium wilt and to explore more effective antifungal drugs against either individual or multiple target proteins of Foc TR4.

  3. The effect of wind on dispersal of splash-borne Xanthomonas citri subsp citri at different heights and distances downwind of canker-infected grapefruit trees

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Xanthomonas citri subsp citri (Xcc), which causes citrus canker, is a major pathogen of grapefruit and other canker-susceptible citrus species and cultivars grown in Florida and elsewhere. It is dispersed by rain splash, and wind promotes the dispersal of the pathogen. The aim of this study was to e...

  4. Fate of Fusarium Toxins during Brewing.

    PubMed

    Habler, Katharina; Geissinger, Cajetan; Hofer, Katharina; Schüler, Jan; Moghari, Sarah; Hess, Michael; Gastl, Martina; Rychlik, Michael

    2017-01-11

    Some information is available about the fate of Fusarium toxins during the brewing process, but only little is known about the single processing steps in detail. In our study we produced beer from two different barley cultivars inoculated with three different Fusarium species, namely, Fusarium culmorum, Fusarium sporotrichioides, and Fusarium avenaceum, producing a wide range of mycotoxins such as type B trichothecenes, type A trichothecenes, and enniatins. By the use of multi-mycotoxin LC-MS/MS stable isotope dilution methods we were able to follow the fate of Fusarium toxins during the entire brewing process. In particular, the type B trichothecenes deoxynivalenol, 3-acetyldeoxynivalenol, and 15-acetyldeoxynivalenol showed similar behaviors. Between 35 and 52% of those toxins remained in the beer after filtration. The contents of the potentially hazardous deoxynivalenol-3-glucoside and the type A trichothecenes increased during mashing, but a rapid decrease of deoxynivalenol-3-glucoside content was found during the following steps of lautering and wort boiling. The concentration of enniatins greatly decreased with the discarding of spent grains or finally with the hot break. The results of our study show the retention of diverse Fusarium toxins during the brewing process and allow for assessing the food safety of beer regarding the monitored Fusarium mycotoxins.

  5. Resistance to Fusarium wilt in chickpea

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Fusarium wilt of chickpea, caused by the fungal pathogen Fusarium oxysporum f. sp. ciceris (Foc), is a destructive disease and is distributed in almost all chickpea producing regions of the world. Foc has eight physiological races designated as 0, 1A, 1B/C, 2, 3, 4, 5 and 6. The races are different...

  6. Bacterial canker of plum trees, caused by Pseudomonas syringae pathovars, as a serious threat for plum production in the Netherlands.

    PubMed

    Wenneker, M; Janse, J D; De Bruine, J A

    2011-01-01

    In the Netherlands, bacterial canker in plum trees (Prunus domestica) is a serious and recent problem in plum production. It is caused by Pseudomonas syringae pathovars syringae and morsprunorum. The trunks of the affected plum trees are girdled by bacterial cankers resulting in sudden death of infected trees in 3-4 years after planting. Disease incidences can be very high, and sometimes complete orchards have to be removed. Recently, plum cultivation in the Netherlands has changed from a relatively extensive into an intensive cultivation. However, due to the risks of losses of trees due to bacterial canker, growers are reluctant to plant new plum orchards. In general nurseries and fruit growers are not familiar with bacterial diseases and lack knowledge in order to prevent infections. Therefore, control strategies to manage plum decline have to be developed.

  7. Fungus Resistant XM205 Nonmetallic Cartridge Case,

    DTIC Science & Technology

    CARTRIDGE CASES, *FUNGICIDES, FUNGUS PROOFING, FUNGUS DETERIORATION, RESISTANCE, NITROCELLULOSE, POLYMERS, FIBERS, SYNTHETIC FIBERS, MATERIALS, ZINC COMPOUNDS, ORGANIC COMPOUNDS, ORGANIC SULFUR COMPOUNDS.

  8. IDENTIFICATION OF DIFFERENT FUSARIUM SPP. IN ALLIUM SPP. IN GERMANY.

    PubMed

    Boehnke, B; Karlovsky, P; Pfohl, K; Gamliel, A; Isack, Y; Dehne, H W

    2015-01-01

    In 2013 Allium cepa bulbs from different fields in Northern and Southern Germany, seeds and sets from onion breeders were analysed for infestation with Fusarium species. The same investigation was done in 2014 with different edible Allium spp. from local markets. Different Fusarium spp. were isolated and identified by morphological characterisation. 24 different Fusarium spp. were identified. The diversity of Fusarium spp. and the intensity of infestation was higher on edible bulbs compared to the younger sets and seeds. The analysed onions and other edible Allium spp. from local markets showed also high contents of different Fusarium species. The most prevalent identified Fusarium sp. in the analysed Allium spp. in Germany was Fusarium oxysporum which can cause the Fusarium Basal Rot, followed by Fusarium solani. Fusarium proliferatum, which can cause the Fusarium Salmon Blotch in onions, could be detected in about half of the sampled onion fields and in approximately 10% of all analysed onions from fields. Also in the onion sets, on the surface of the seeds and in other edible Allium spp. F. proliferatum could be identified. Besides F. proliferatum, further mycotoxin producing Fusarium spp. like Fusarium equiseti or Fusarium tricinctum were identified. Other Fusarium spp. like Fusarium sporotrichioides and Fusarium poae were first described in Allium sp. in this study. The two most prevalent Fusarium spp. F. oxysporum and F. solani are able to produce mycotoxins like enniatins, fumonisins, moniliformin and T-2 toxins. Fusarium sp. like F. proliferatum, F. equiseti and F. tricinctum are able to produce additional toxins like beauvericins, zearalenone and diacetoscirpenol. This high number of Fusarium spp., which are able to produce a broad spectrum of different mycotoxins, could be a potential health risk for human beings and livestock.

  9. Amplification of DNA of Xanthomonas axonopodis pv. citri from historic citrus canker herbarium specimens.

    PubMed

    Li, Wenbin; Brlansky, Ronald H; Hartung, John S

    2006-05-01

    Herbaria are important resources for the study of the origins and dispersal of plant pathogens, particularly bacterial plant pathogens that incite local lesions in which large numbers of pathogen genomes are concentrated. Xanthomonas axonopodis pv. citri (Xac), the causal agent of citrus bacterial canker disease, is a notable example of such a pathogen. The appearance of novel strains of the pathogen in Florida and elsewhere make it increasingly important to understand the relationships among strains of this pathogen. USDA-ARS at Beltsville, Maryland maintains approximately 700 herbarium specimens with citrus canker disease lesions up to 90 years old, originally collected from all over the world, and so is an important resource for phytogeographic studies of this bacterium. Unfortunately, DNA in herbarium specimens is degraded and may contain high levels of inhibitors of PCR. In this study, we compared a total of 23 DNA isolation techniques in combination with 31 novel primer pairs in order to develop an efficient protocol for the analysis of Xac DNA in herbarium specimens. We identified the most reliable extraction method, identified in terms of successful amplification by our panel of 31 primer pairs. We also identified the most robust primer pairs, identified as successful in the largest number of extracts prepared by different methods. We amplified Xac genomic sequences up to 542 bp long from herbarium samples up to 89 years old. Primers varied in effectiveness, with some primer pairs amplifying Xac DNA from a 1/10,000 dilution of extract from a single lesion from a citrus canker herbarium specimen. Our methodology will be useful to identify pathogens and perform molecular analyses of bacterial and possibly fungal genomes from herbarium specimens.

  10. Positive selection is the main driving force for evolution of citrus canker-causing Xanthomonas.

    PubMed

    Zhang, Yunzeng; Jalan, Neha; Zhou, Xiaofeng; Goss, Erica; Jones, Jeffrey B; Setubal, João C; Deng, Xiaoling; Wang, Nian

    2015-10-01

    Understanding the evolutionary history and potential of bacterial pathogens is critical to prevent the emergence of new infectious bacterial diseases. Xanthomonas axonopodis subsp. citri (Xac) (synonym X. citri subsp. citri), which causes citrus canker, is one of the hardest-fought plant bacterial pathogens in US history. Here, we sequenced 21 Xac strains (14 XacA, 3 XacA* and 4 XacA(w)) with different host ranges from North America and Asia and conducted comparative genomic and evolutionary analyses. Our analyses suggest that acquisition of beneficial genes and loss of detrimental genes most likely allowed XacA to infect a broader range of hosts as compared with XacA(w) and XacA*. Recombination was found to have occurred frequently on the relative ancient branches, but rarely on the young branches of the clonal genealogy. The ratio of recombination/mutation ρ/θ was 0.0790±0.0005, implying that the Xac population was clonal in structure. Positive selection has affected 14% (395 out of 2822) of core genes of the citrus canker-causing Xanthomonas. The genes affected are enriched in 'carbohydrate transport and metabolism' and 'DNA replication, recombination and repair' genes (P<0.05). Many genes related to virulence, especially genes involved in the type III secretion system and effectors, are affected by positive selection, further highlighting the contribution of positive selection to the evolution of citrus canker-causing Xanthomonas. Our results suggest that both metabolism and virulence genes provide advantages to endow XacA with higher virulence and a wider host range. Our analysis advances our understanding of the genomic basis of specialization by positive selection in bacterial evolution.

  11. Pseudomonas protegens CS1 from the lemon phyllosphere as a candidate for citrus canker biocontrol agent.

    PubMed

    Michavila, G; Adler, C; De Gregorio, P R; Lami, M J; Caram Di Santo, M C; Zenoff, A M; de Cristobal, R E; Vincent, P A

    2017-02-14

    Citrus canker is a worldwide-distributed disease caused by Xanthomonas citri subsp. citri. One of the most used strategies to control the disease is centred on copper-based compounds that cause environmental problems. Therefore, it is of interest to develop new strategies to manage the disease. Previously, we reported the ability of the siderophore pyochelin, produced by the opportunistic human pathogen Pseudomonas aeruginosa, to inhibit in vitro several bacterial species, including X. citri subsp. citri. The action mechanism, addressed with the model bacterium Escherichia coli, was connected to the generation of reactive oxygen species (ROS). This work aimed to find a non-pathogenic strain from the lemon phyllosphere that would produce pyochelin and therefore serve in canker biocontrol. An isolate that retained its capacity to colonise the lemon phyllosphere and inhibit X. citri subsp. citri was selected and characterised as Pseudomonas protegens CS1. From a liquid culture of this strain, the active compound was purified and identified as the pyochelin enantiomer, enantio-pyochelin. Using the producing strain and the pure compound, both in vitro and in vivo, we determined that the action mechanism of X. citri subsp. citri inhibition also involved the generation of ROS. Finally, the potential application of P. protegens CS1 was evaluated by spraying the bacterium in a model that mimics the natural X. citri subsp. citri infection. The ability of P. protegens CS1 to reduce canker formation makes this strain an interesting candidate as a biocontrol agent.

  12. Analysis of Quality-Related Parameters in Mature Kernels of Polygalacturonase Inhibiting Protein (PGIP) Transgenic Bread Wheat Infected with Fusarium graminearum.

    PubMed

    Masci, Stefania; Laino, Paolo; Janni, Michela; Botticella, Ermelinda; Di Carli, Mariasole; Benvenuto, Eugenio; Danieli, Pier Paolo; Lilley, Kathryn S; Lafiandra, Domenico; D'Ovidio, Renato

    2015-04-22

    Fusarium head blight, caused by the fungus Fusarium graminearum, has a detrimental effect on both productivity and qualitative properties of wheat. To evaluate its impact on wheat flour, we compared its effect on quality-related parameters between a transgenic bread wheat line expressing a bean polygalacturonase inhibiting protein (PGIP) and its control line. We have compared metabolic proteins, the amounts of gluten proteins and their relative ratios, starch content, yield, extent of pathogen contamination, and deoxynivalenol (DON) accumulation. These comparisons showed that Fusarium significantly decreases the amount of starch in infected control plants, but not in infected PGIP plants. The flour of PGIP plants contained also a lower amount of pathogen biomass and DON accumulation. Conversely, both gluten and metabolic proteins were not significantly influenced either by the transgene or by fungal infection. These results indicate that the transgenic PGIP expression reduces the level of infection, without changing significantly the wheat seed proteome and other quality-related parameters.

  13. Draft genome sequence and chemical profiling of Fusarium langsethiae, an emerging producer of type A trichothecenes.

    PubMed

    Lysøe, Erik; Frandsen, Rasmus J N; Divon, Hege H; Terzi, Valeria; Orrù, Luigi; Lamontanara, Antonella; Kolseth, Anna-Karin; Nielsen, Kristian F; Thrane, Ulf

    2016-03-16

    Fusarium langsethiae is a widespread pathogen of small grain cereals, causing problems with T-2 and HT-2 toxin contamination in grains every year. In an effort to better understand the biology of this fungus, we present a draft genome sequence of F. langsethiae Fl201059 isolated from oats in Norway. The assembly was fragmented, but reveals a genome of approximately 37.5 Mb, with a GC content around 48%, and 12,232 predicted protein-coding genes. Focusing on secondary metabolism we identified candidate genes for 12 polyketide synthases, 13 non-ribosomal peptide synthetases, and 22 genes for terpene/isoprenoid biosynthesis. Some of these were found to be unique compared to sequence databases. The identified putative Tri5 cluster was highly syntenic to the cluster reported in F. sporotrichioides. Fusarium langsethiae Fl201059 produces a high number of secondary metabolites on Yeast Extract Sucrose (YES) agar medium, dominated by type A trichothecenes. Interestingly we found production of glucosylated HT-2 toxin (Glu-HT-2), previously suggested to be formed by the host plant and not by the fungus itself. In greenhouse inoculations of F. langsethiae Fl201059 on barley and oats, we detected the type A trichothecenes: neosolaniol, HT-2 toxin, T-2 toxin, Glu-HT-2 and numerous derivatives of these.

  14. Interactions of Bacillus mojavensis and Fusarium verticillioides with a benzoxazolinone (BOA) and its transformation product, APO.

    PubMed

    Bacon, Charles W; Hinton, Dorothy M; Glenn, Anthony E; Macías, Francisco A; Marin, David

    2007-10-01

    The benzoxazolinones, specifically benzoxazolin-2(3H)-one (BOA), are important transformation products of the benzoxazinones that can serve as allelochemicals providing resistance to maize from pathogenic bacteria, fungi, and insects. However, maize pathogens such as Fusarium verticillioides are capable of detoxifying the benzoxazolinones to 2-aminophenol (AP), which is converted to the less toxic N-(2-hydroxyphenyl) malonamic acid (HPMA) and 2-acetamidophenol (HPAA). As biocontrol strategies that utilize a species of endophytic bacterium, Bacillus mojavensis, are considered efficacious as a control of this Fusarium species, the in vitro transformation and effects of BOA on growth of this bacterium was examined relative to its interaction with strains of F. verticillioides. The results showed that a red pigment was produced and accumulated only on BOA-amended media when wild type and the progeny of genetic crosses of F. verticillioides are cultured in the presence of the bacterium. The pigment was identified as 2-amino-3H-phenoxazin-3-one (APO), which is a stable product. The results indicate that the bacterium interacts with the fungus preventing the usual transformation of AP to the nontoxic HPMA, resulting in the accumulation of higher amounts of APO than when the fungus is cultured alone. APO is highly toxic to F. verticillioides and other organisms. Thus, an enhanced biocontrol is suggested by this in vitro study.

  15. Diversity of the exoproteome of Fusarium graminearum grown on plant cell wall.

    PubMed

    Phalip, Vincent; Delalande, François; Carapito, Christine; Goubet, Florence; Hatsch, Didier; Leize-Wagner, Emmanuelle; Dupree, Paul; Dorsselaer, Alain Van; Jeltsch, Jean-Marc

    2005-12-01

    The exoproteome of the fungus Fusarium graminearum grown on glucose and on hop (Humulus lupulus, L.) cell wall has been investigated. The culture medium was found to contain a higher quantity of proteins and the proteins are more diverse when the fungus is grown on cell wall. Using both 1D and 2D electrophoresis followed by mass spectrometry analysis and protein identification based on similarity searches, 84 unique proteins were identified in the cell wall-grown fungal exoproteome. Many are putatively implicated in carbohydrate metabolism, mainly in cell wall polysaccharide degradation. The predicted carbohydrate-active enzymes fell into 24 different enzymes classes, and up to eight different proteins within a same class are secreted. This indicates that fungal metabolism becomes oriented towards synthesis and secretion of a whole arsenal of enzymes able to digest almost the complete plant cell wall. Cellobiohydrolase is one of the only four proteins found both after growth on glucose and on plant cell wall and we propose that this enzyme could act as a sensor of the extracellular environment. Extensive knowledge of this very diverse F. graminearum exoproteome is an important step towards the full understanding of Fusarium/plants interactions.

  16. Identification and characterization of gushing-active hydrophobins from Fusarium graminearum and related species.

    PubMed

    Sarlin, Tuija; Kivioja, Teemu; Kalkkinen, Nisse; Linder, Markus B; Nakari-Setälä, Tiina

    2012-04-01

    Fungal infection of barley and malt, particularly by the Fusarium species, is a direct cause of spontaneous overfoaming of beer, referred to as gushing. We have shown previously that small fungal proteins, hydrophobins, act as gushing-inducing factors in beer. The aim of our present study was to isolate and characterize hydrophobins from a gushing-active fungus, Fusarium graminearum (teleomorph Gibberella zeae) and related species. We generated profile hidden Markov models (profile HMMs) for the hydrophobin classes Ia, Ib and II from the multiple sequence alignments of their known members available in public domain databases. We searched the published Fusarium graminearum genome with the Markov models. The best matching sequences and the corresponding genes were isolated from F. graminearum and the related species F. culmorum and F. poae by PCR and characterized. One each of the putative F. graminearum and F. poae hydrophobin genes were expressed in the heterologous host Trichoderma reesei. The proteins corresponding to the genes were purified and identified as hydrophobins and named GzHYD5 and FpHYD5, respectively. Concentrations of 0.003 ppm of these hydrophobins were observed to induce vigorous beer gushing.

  17. Fusarium solani onychomycosis of the thumbnail coinfected with Pseudomonas aeruginosa: report of two cases.

    PubMed

    Yang, Yun-Seok; Ahn, Jae-Jun; Shin, Min-Kyung; Lee, Mu-Hyoung

    2011-03-01

    Fusarium species are non-dermatophytic moulds, which are commonly known soil saprophytes and important plant pathogens, and have been frequently reported to be aetiological agents of opportunistic infections in humans. The prevalence of onychomycosis caused by Fusarium species varies in the literature because of geographical differences in mould distribution and diagnostic methods. Onychomycosis caused by Fusarium species is considered rare in Korea, and only four cases have been described to date. Pseudomonas aeruginosa also can infect nails and cause green nail syndrome, and recent research has shown that fungal infection may potentiate the colonisation or growth of P. aeruginosa within a nail. Furthermore, such coinfection with P. aeruginosa can prevent the isolation of the fungus because of bacterial overgrowth in culture. The authors report the cases of two immunocompetent patients with F. solani onychomycosis coinfected with P. aeruginosa. Both presented with a greenish/yellowish discolouration and thickening of a thumbnail, and were treated with systemic ciprofloxacin in combination with itraconazole or terbinafine.

  18. Molecular identification of Fusarium species isolated from transgenic insect-resistant cotton plants in Mexicali valley, Baja California.

    PubMed

    Gonzalez-Soto, T; González-Mendoza, D; Troncoso-Rojas, R; Morales-Trejo, A; Ceceña-Duran, C; Garcia-Lopez, A; Grimaldo-Juarez, O

    2015-10-02

    Cotton production in the Mexicali valley is adversely affected by wilt and root rot disease associated with Fusarium species. In the present study, we sought to isolate and identify the Fusarium species in the rhizosphere of transgenic insect-resistant cotton plants grown in the Mexicali valley. Our analyses isolated four native fungi from the rhizosphere of cotton plants, namely, T-ICA01, T-ICA03, T-ICA04, and T-ICA08. These fungal isolates were categorized as belonging to Fusarium solani using their phenotypic characteristics and ITS region sequence data. Examination of the infection index showed that T-ICA03 and T-ICA04 caused systemic colonization (90%) of seeds followed by the occurrence of radicle and coleoptile decay. In contrast, T-ICA08 strain was less pathogenic against seed tissues (40%) in comparison to the other strains isolated. Our study showed that in transgenic insect-resistant cotton the disease "Fusarium wilt" is caused by the fungus, F. solani. Future studies are necessary to characterize the F. solani populations to determine whether phenological stages might influence the genetic diversity of the fungal populations present.

  19. An Endohyphal Bacterium (Chitinophaga, Bacteroidetes) Alters Carbon Source Use by Fusarium keratoplasticum (F. solani Species Complex, Nectriaceae)

    PubMed Central

    Shaffer, Justin P.; U'Ren, Jana M.; Gallery, Rachel E.; Baltrus, David A.; Arnold, A. Elizabeth

    2017-01-01

    Bacterial endosymbionts occur in diverse fungi, including members of many lineages of Ascomycota that inhabit living plants. These endosymbiotic bacteria (endohyphal bacteria, EHB) often can be removed from living fungi by antibiotic treatment, providing an opportunity to assess their effects on functional traits of their fungal hosts. We examined the effects of an endohyphal bacterium (Chitinophaga sp., Bacteroidetes) on substrate use by its host, a seed-associated strain of the fungus Fusarium keratoplasticum, by comparing growth between naturally infected and cured fungal strains across 95 carbon sources with a Biolog® phenotypic microarray. Across the majority of substrates (62%), the strain harboring the bacterium significantly outperformed the cured strain as measured by respiration and hyphal density. These substrates included many that are important for plant- and seed-fungus interactions, such as D-trehalose, myo-inositol, and sucrose, highlighting the potential influence of EHB on the breadth and efficiency of substrate use by an important Fusarium species. Cases in which the cured strain outperformed the strain harboring the bacterium were observed in only 5% of substrates. We propose that additive or synergistic substrate use by the fungus-bacterium pair enhances fungal growth in this association. More generally, alteration of the breadth or efficiency of substrate use by dispensable EHB may change fungal niches in short timeframes, potentially shaping fungal ecology and the outcomes of fungal-host interactions. PMID:28382021

  20. Unconventional Recombination in the Mating Type Locus of Heterothallic Apple Canker Pathogen Valsa mali

    PubMed Central

    Yin, Zhiyuan; Ke, Xiwang; Li, Zhengpeng; Chen, Jiliang; Gao, Xiaoning; Huang, Lili

    2017-01-01

    Sexual reproduction in filamentous ascomycetes is controlled by the mating type (MAT) locus, including two idiomorphs MAT1-1 and MAT1-2. Understanding the MAT locus can provide clues for unveiling the sexual development and virulence factors for fungal pathogens. The genus Valsa (Sordariomycetes, Diaporthales) contains many tree pathogens responsible for destructive canker diseases. The sexual stage of these ascomycetes is occasionally observed in nature, and no MAT locus has been reported to date. Here, we identified the MAT locus of the apple canker pathogen Valsa mali, which causes extensive damage, and even death, to trees. V. mali is heterothallic in that each isolate carries either the MAT1-1 or MAT1-2 idiomorph. However, the MAT structure is distinct from that of many other heterothallic fungi in the Sordariomycetes. Two flanking genes, COX13 and APN2, were coopted into the MAT locus, possibly by intrachromosomal rearrangement. After the acquisition of foreign genes, unequal recombination occurred between MAT1-1/2 idiomorphs, resulting in a reverse insertion in the MAT1-2 idiomorph. Evolutionary analysis showed that the three complete MAT1-1-2, COX13, and APN2 genes in this region diverged independently due to different selection pressure. Null hypothesis tests of a 1:1 MAT ratio of 86 V. mali isolates from four different provinces showed a relatively balanced distribution of the two idiomorphs in the fields. These results provide insights into the evolution of the mating systems in Sordariomycetes. PMID:28228472

  1. Occurrence of shallow bark canker of walnut (Juglans regia) in southern provinces of Iran.

    PubMed

    Yousefikopaei, F; Taghavi, S M; Banihashemi, Z

    2007-05-01

    From April 2001 to November 2002, samples of walnut branches and trunks with symptoms of shallow bark canker were collected from Fars and Kohgiluyeh-va-Boyerahmad provinces. Symptoms of the disease were small cracks in the bark of the trunk and scaffold branches of mature trees with dark watery exudates which stained the affected trunk or limb. By removal of phelloderm, extensive necrosis of the underlying tissues was observed. In some cases, necrosis extended to cambium and outer xylem. Sixty-one strains of a bacterium were isolated from infected tissues using EMB and YDC media. On the basis of standard biochemical and physiological tests the bacterium was identified as Brenneria nigrifluens. The pathogen was found to be wide-spread in the provinces. Isolates were compared by physiological and biochemical characters, antibiotic sensitivity and protein electrophoretic pattern. Most of the strains were fairly similar in phenotypic features and electrophoretic profiles ofwhole-cell proteins were similar to each other and to reference strain (B. nigrifluens 5D313). Inoculation of 1-2 years-old walnut seedlings in May and June produced blackening symptoms and the bacterium survived for long period in infected tissues. This is the first report of the shallow bark canker of walnut in southern Iran.

  2. Isolation and Characterization of Bacteriophages Against Pseudomonas syringae pv. actinidiae Causing Bacterial Canker Disease in Kiwifruit.

    PubMed

    Yu, Ji-Gang; Lim, Jeong-A; Song, Yu-Rim; Heu, Sunggi; Kim, Gyoung Hee; Koh, Young Jin; Oh, Chang-Sik

    2016-02-01

    Pseudomonas syringae pv. actinidiae causes bacterial canker disease in kiwifruit. Owing to the prohibition of agricultural antibiotic use in major kiwifruit-cultivating countries, alternative methods need to be developed to manage this disease. Bacteriophages are viruses that specifically infect target bacteria and have recently been reconsidered as potential biological control agents for bacterial pathogens owing to their specificity in terms of host range. In this study, we isolated bacteriophages against P. syringae pv. actinidiae from soils collected from kiwifruit orchards in Korea and selected seven bacteriophages for further characterization based on restriction enzyme digestion patterns of genomic DNA. Among the studied bacteriophages, two belong to the Myoviridae family and three belong to the Podoviridae family, based on morphology observed by transmission electron microscopy. The host range of the selected bacteriophages was confirmed using 18 strains of P. syringae pv. actinidiae, including the Psa2 and Psa3 groups, and some were also effective against other P. syringae pathovars. Lytic activity of the selected bacteriophages was sustained in vitro until 80 h, and their activity remained stable up to 50°C, at pH 11, and under UV-B light. These results indicate that the isolated bacteriophages are specific to P. syringae species and are resistant to various environmental factors, implying their potential use in control of bacterial canker disease in kiwifruits.

  3. Additive roles of PthAs in bacterial growth and pathogenicity associated with nucleotide polymorphisms in effector-binding elements of citrus canker susceptibility genes.

    PubMed

    Abe, Valeria Yukari; Benedetti, Celso Eduardo

    2016-10-01

    Citrus canker, caused by Xanthomonas citri, affects most commercial citrus varieties. All X. citri strains possess at least one transcription activator-like effector of the PthA family that activates host disease susceptibility (S) genes. The X. citri strain 306 encodes four PthA effectors; nevertheless, only PthA4 is known to elicit cankers on citrus. As none of the PthAs act as avirulence factors on citrus, we hypothesized that PthAs 1-3 might also contribute to pathogenicity on certain hosts. Here, we show that, although PthA4 is indispensable for canker formation in six Brazilian citrus varieties, PthAs 1 and 3 contribute to canker development in 'Pera' sweet orange, but not in 'Tahiti' lemon. Deletions in two or more pthA genes reduce bacterial growth in planta more pronouncedly than single deletions, suggesting an additive role of PthAs in pathogenicity and bacterial fitness. The contribution of PthAs 1 and 3 in canker formation in 'Pera' plants does not correlate with the activation of the canker S gene, LOB1 (LATERAL ORGAN BOUNDARIES 1), but with the induction of other PthA targets, including LOB2 and citrus dioxygenase (DIOX). LOB1, LOB2 and DIOX show differential PthA-dependent expression between 'Pera' and 'Tahiti' plants that appears to be associated with nucleotide polymorphisms found at or near PthA-binding sites. We also present evidence that LOB1 activation alone is not sufficient to elicit cankers on citrus, and that DIOX acts as a canker S gene in 'Pera', but not 'Tahiti', plants. Our results suggest that the activation of multiple S genes, such as LOB1 and DIOX, is necessary for full canker development.

  4. The HPLC-Fluorescence Detection of Coumarins in ‘Hamlin’ Sweet Orange and ‘Marsh’ Grapefruit Leaf Cankers

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Canker is a devastating disease for the citrus fresh fruit market and is caused by the pathogenic bacterium Xanthomonas citri var. citri (Xcc). Infection occurs by bacterial penetration through physical damage of leaves, peel and stems, and also by bacterial entry through the stomates of these photo...

  5. Transcriptional Profiling of Canker-Resistant Transgenic Sweet Orange (Citrus sinensis Osbeck) Constitutively Overexpressing a Spermidine Synthase Gene

    PubMed Central

    Fu, Xing-Zheng; Liu, Ji-Hong

    2013-01-01

    Citrus canker disease caused by Xanthomonas citri subsp. citri (Xcc) is one of the most devastating diseases affecting the citrus industry worldwide. In our previous study, the canker-resistant transgenic sweet orange (Citrus sinensis Osbeck) plants were produced via constitutively overexpressing a spermidine synthase. To unravel the molecular mechanisms underlying Xcc resistance of the transgenic plants, in the present study global transcriptional profiling was compared between untransformed line (WT) and the transgenic line (TG9) by hybridizing with Affymetrix Citrus GeneChip. In total, 666 differentially expressed genes (DEGs) were identified, 448 upregulated, and 218 downregulated. The DEGs were classified into 33 categories after Gene ontology (GO) annotation, in which 68 genes are in response to stimulus and involved in immune system process, 12 genes are related to cell wall, and 13 genes belong to transcription factors. These genes and those related to starch and sucrose metabolism, glutathione metabolism, biosynthesis of phenylpropanoids, and plant hormones were hypothesized to play major roles in the canker resistance of TG9. Semiquantitative RT-PCR analysis showed that the transcript levels of several candidate genes in TG9 were significantly higher than in WT both before and after Xcc inoculation, indicating their potential association with canker disease. PMID:23509803

  6. Characteristics of the perception of different severity measures of citrus canker and the relations between the various symptom types

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Citrus canker is a disease of citrus and is caused by the bacterial pathogen Xanthomonas axonopodis pv citri (Xac). Ways of managing the disease are being sought, and accurate, precise, reproducible disease assessment is needed for monitoring epidemics. The objective of this study was to investigate...

  7. Visual rating and the use of image analysis for assessing different symptoms of citrus canker on grapefruit leaves

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Citrus canker is caused by the bacterial pathogen Xanthomonas axonopodis pv citri (Xac) and infects several citrus species in wet tropical and subtropical citrus growing regions. Accurate, precise and reproducible disease assessment is needed for monitoring epidemics and disease response in breeding...

  8. Overexpression of a modified plant thionin enhances disease resistance to citrus canker and huanglongbing (HLB, citrus greening)

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Huanglongbing (HLB or citrus greening disease) caused by Candidatus Liberibacter asiaticus (Las) is a great threat to the United States citrus industry. Citrus canker is also an economically important disease associated with a bacterial pathogen (Xanthomonas citri). In this study, we characterized e...

  9. Under severe HLB and citrus canker pressure, 'Triumph' and 'Jackson' perform better than 'Flame' and 'Marsh' grapefruit

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Huanglongbing (HLB) and Citrus Canker (CC) threaten the viability of Florida grapefruit production. ‘Triumph’ (T), reportedly a grapefruit/sweet orange hybrid, is similar to seedy white grapefruit with earlier maturity and lower bitterness. ‘Jackson’ (J) is a low-seeded budsport of ‘Triumph’. Tree h...

  10. Under severe citrus canker and HLB (Huanglongbing) pressure, Triumph and Jackson perform better than Flame and Marsh grapefruit

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Huanglongbing (HLB) and Citrus Canker (CC) threaten the viability of Florida grapefruit production. Triumph (T), reportedly a grapefruit/sweet orange hybrid, is similar to seedy white grapefruit with earlier maturity and lower bitterness. Jackson (J) is a low-seeded budsport of Triumph. Tree health ...

  11. Transcriptional profiling of canker-resistant transgenic sweet orange (Citrus sinensis Osbeck) constitutively overexpressing a spermidine synthase gene.

    PubMed

    Fu, Xing-Zheng; Liu, Ji-Hong

    2013-01-01

    Citrus canker disease caused by Xanthomonas citri subsp. citri (Xcc) is one of the most devastating diseases affecting the citrus industry worldwide. In our previous study, the canker-resistant transgenic sweet orange (Citrus sinensis Osbeck) plants were produced via constitutively overexpressing a spermidine synthase. To unravel the molecular mechanisms underlying Xcc resistance of the transgenic plants, in the present study global transcriptional profiling was compared between untransformed line (WT) and the transgenic line (TG9) by hybridizing with Affymetrix Citrus GeneChip. In total, 666 differentially expressed genes (DEGs) were identified, 448 upregulated, and 218 downregulated. The DEGs were classified into 33 categories after Gene ontology (GO) annotation, in which 68 genes are in response to stimulus and involved in immune system process, 12 genes are related to cell wall, and 13 genes belong to transcription factors. These genes and those related to starch and sucrose metabolism, glutathione metabolism, biosynthesis of phenylpropanoids, and plant hormones were hypothesized to play major roles in the canker resistance of TG9. Semiquantitative RT-PCR analysis showed that the transcript levels of several candidate genes in TG9 were significantly higher than in WT both before and after Xcc inoculation, indicating their potential association with canker disease.

  12. Brachypodium distachyon: a new pathosystem to study Fusarium head blight and other Fusarium diseases of wheat

    PubMed Central

    2011-01-01

    Background Fusarium species cause Fusarium head blight (FHB) and other important diseases of cereals. The causal agents produce trichothecene mycotoxins such as deoxynivalenol (DON). The dicotyledonous model species Arabidopsis thaliana has been used to study Fusarium-host interactions but it is not ideal for model-to-crop translation. Brachypodium distachyon (Bd) has been proposed as a new monocotyledonous model species for functional genomic studies in grass species. This study aims to assess the interaction between the most prevalent FHB-causing Fusarium species and Bd in order to develop and exploit Bd as a genetic model for FHB and other Fusarium diseases of wheat. Results The ability of Fusarium graminearum and Fusarium culmorum to infect a range of Bd tissues was examined in various bioassays which showed that both species can infect all Bd tissues examined, including intact foliar tissues. DON accumulated in infected spike tissues at levels similar to those of infected wheat spikes. Histological studies revealed details of infection, colonisation and host response and indicate that hair cells are important sites of infection. Susceptibility to Fusarium and DON was assessed in two Bd ecotypes and revealed variation in resistance between ecotypes. Conclusions Bd exhibits characteristics of susceptibility highly similar to those of wheat, including susceptibility to spread of disease in the spikelets. Bd is the first reported plant species to allow successful infection on intact foliar tissues by FHB-causing Fusarium species. DON appears to function as a virulence factor in Bd as it does in wheat. Bd is proposed as a valuable model for undertaking studies of Fusarium head blight and other Fusarium diseases of wheat. PMID:21639892

  13. Draft Genome Sequences of Pectobacterium carotovorum subsp. actinidiae ICMP 19971 and ICMP 19972, Two Strains Isolated from Actinidia chinensis with Symptoms of Summer Canker in South Korea

    PubMed Central

    Panda, Preetinanda; Taylor, Robert; Pitman, Andrew R.

    2017-01-01

    ABSTRACT Pectobacterium carotovorum subsp. actinidiae is the causal agent of summer canker in kiwifruit plants in South Korea. We report here the draft genome sequences of two P. carotovorum subsp. actinidiae strains, ICMP 19971 and ICMP 19972, which were originally isolated from Actinidia chinensis with symptoms of summer canker. These genome sequences will aid in the identification of genetic traits associated with their unusual capacity to cause canker and help understanding of the threat these exotic enterobacteria pose to the New Zealand kiwifruit industry. PMID:28385839

  14. Efficacy of sludge and manure compost amendments against Fusarium wilt of cucumber.

    PubMed

    Huang, Xiao; Shi, Dezhi; Sun, Faqian; Lu, Haohao; Liu, Jingjing; Wu, Weixiang

    2012-11-01

    Fusarium wilt of cucumber caused by the fungus, Fusarium oxysporum, is one of the most destructive soilborne diseases and can result in serious economic loss. No efficient fungicide is currently available to control the disease. The aim of this study was to examine the disease suppression ability of pig manure and sludge composts in peat-based container media and explore the possible disease suppression mechanisms. Pig manure and sewage sludge compost were made in laboratory-scale tanks. Plant growth media were formulated with peat mixture and compost (or 60 °C heated compost) in a 4:1 ratio (v/v). Cucumber seedlings were artificially inoculated with F. oxysporum conidia (5 × 10(5) conidia mL(-1)) by the root-dip method. Cucumber Fusarium wilt was effectively suppressed in sludge compost-amended media, while the disease suppression effect of pig manure compost was limited. The ammonia levels in the manure compost-amended media were significantly higher than those of sludge compost-amended media, which could explain its lower disease suppression ability. Heated composts behaved similarly with respect to disease suppression. Adding composts increased microbial biomass, microbial activity, and the microbial diversity of the growth media. PCR-DGGE results indicated that the fungal community had a significant correlation to the disease severity. The artificially inoculated pathogen was retrieved in all treatments and one possible biocontrol agent was identified as a strain of F. oxysporum by phylogenetic analyses. The results indicated that the sludge compost used in this study could be applied as a method for biocontrol of cucumber Fusarium wilt.

  15. Zirconia enrichment in zircon sand by selective fungus-mediated bioleaching of silica.

    PubMed

    Bansal, Vipul; Syed, Asad; Bhargava, Suresh K; Ahmad, Absar; Sastry, Murali

    2007-04-24

    One of the important routes for the production of zirconia is by chemical treatment and removal of silica from zircon sand (ZrSixOy). We present here a completely green chemistry approach toward enrichment of zirconia in zircon sand; this is based on the reaction of the fungus Fusarium oxysporum with zircon sand by a process of selective extracellular bioleaching of silica nanoparticles. Since this reaction does not result in zirconia being simultaneously leached out from the sand, there is a consequent enrichment of the zirconia component in zircon sand. We believe that fungal enzymes specifically hydrolyze the silicates present in the sand to form silicic acid, which on condensation by certain other fungal enzymes results in room-temperature synthesis of silica nanoparticles. This fungus-mediated twofold approach might have vast commercial implications in low-cost, ecofriendly, room-temperature syntheses of technologically important oxide nanomaterials from potentially cheap naturally available raw materials like zircon sand.

  16. Diplopyrone, a new phytotoxic tetrahydropyranpyran-2-one produced by Diplodia mutila, a fungus pathogen of cork oak.

    PubMed

    Evidente, Antonio; Maddau, Lucia; Spanu, Emanuela; Franceschini, Antonio; Lazzaroni, Silvia; Motta, Andrea

    2003-02-01

    A new phytotoxic monosubstituted tetrahydropyranpyran-2-one, named diplopyrone (1), was isolated from the liquid culture filtrates of Diplodia mutila, a plant pathogenic fungus causing a form of canker disease of cork oak (Quercus suber). Diplopyrone was characterized, using spectroscopic and chemical methods, as 6-[(1S)-1-hydroxyethyl]-2,4a,6,8a-tetrahydropyran[3,2-b]pyran-2-one. The absolute stereochemistry of the chiral secondary hydroxylated carbon (C-9), determined by application of Mosher's method, proved to be S. Diplopyrone assayed at a 0.01-0.1 mg/mL concentration range caused necrosis and wilting on cork oak cuttings. On a nonhost plant, tomato, diplopyrone caused brown discoloration or stewing on the stem.

  17. IAA-producing Penicillium sp. NICS01 triggers plant growth and suppresses Fusarium sp.-induced oxidative stress in sesame (Sesamum indicum L.).

    PubMed

    Radhakrishnan, Ramalingam; Shim, Kang-Bo; Lee, Byeong-Won; Hwang, Chung-Dong; Pae, Suk-Bok; Park, Chang-Hwan; Kim, Sung-Up; Lee, Choon-Ki; Baek, In-Youl

    2013-06-28

    Application of rhizospheric fungi is an effective and environmentally friendly method of improving plant growth and controlling many plant diseases. The current study was aimed to identify phytohormone-producing fungi from soil, to understand their roles in sesame plant growth, and to control Fusarium disease. Three predominant fungi (PNF1, PNF2, and PNF3) isolated from the rhizospheric soil of peanut plants were screened for their growth-promoting efficiency on sesame seedlings. Among these isolates, PNF2 significantly increased the shoot length and fresh weight of seedlings compared with controls. Analysis of the fungal culture filtrate showed a higher concentration of indole acetic acid in PNF2 than in the other isolates. PNF2 was identified as Penicillium sp. on the basis of phylogenetic analysis of ITS sequence similarity. The in vitro biocontrol activity of Penicillium sp. against Fusarium sp. was exhibited by a 49% inhibition of mycelial growth in a dual culture bioassay and by hyphal injuries as observed by scanning electron microscopy. In addition, greenhouse experiments revealed that Fusarium inhibited growth in sesame plants by damaging lipid membranes and reducing protein content. Co-cultivation with Penicillium sp. mitigated Fusarium-induced oxidative stress in sesame plants by limiting membrane lipid peroxidation, and by increasing the protein concentration, levels of antioxidants such as total polyphenols, and peroxidase and polyphenoloxidase activities. Thus, our findings suggest that Penicillium sp. is a potent plant growthpromoting fungus that has the ability to ameliorate damage caused by Fusarium infection in sesame cultivation.

  18. Genome editing of the disease susceptibility gene CsLOB1 in citrus confers resistance to citrus canker.

    PubMed

    Jia, Hongge; Zhang, Yunzeng; Orbović, Vladimir; Xu, Jin; White, Frank F; Jones, Jeffrey B; Wang, Nian

    2016-12-09

    Citrus is a highly valued tree crop worldwide, while, at the same time, citrus production faces many biotic challenges, including bacterial canker and Huanglongbing (HLB). Breeding for disease-resistant varieties is the most efficient and sustainable approach to control plant diseases. Traditional breeding of citrus varieties is challenging due to multiple limitations, including polyploidy, polyembryony, extended juvenility and long crossing cycles. Targeted genome editing technology has the potential to shorten varietal development for some traits, including disease resistance. Here, we used CRISPR/Cas9/sgRNA technology to modify the canker susceptibility gene CsLOB1 in Duncan grapefruit. Six independent lines, DLOB 2, DLOB 3, DLOB 9, DLOB 10, DLOB 11 and DLOB 12, were generated. Targeted next-generation sequencing of the six lines showed the mutation rate was 31.58%, 23.80%, 89.36%, 88.79%, 46.91% and 51.12% for DLOB 2, DLOB 3, DLOB 9, DLOB 10, DLOB 11 and DLOB 12, respectively, of the cells in each line. DLOB 2 and DLOB 3 showed canker symptoms similar to wild-type grapefruit, when inoculated with the pathogen Xanthomonas citri subsp. citri (Xcc). No canker symptoms were observed on DLOB 9, DLOB 10, DLOB 11 and DLOB 12 at 4 days postinoculation (DPI) with Xcc. Pustules caused by Xcc were observed on DLOB 9, DLOB 10, DLOB 11 and DLOB 12 in later stages, which were much reduced compared to that on wild-type grapefruit. The pustules on DLOB 9 and DLOB 10 did not develop into typical canker symptoms. No side effects and off-target mutations were detected in the mutated plants. This study indicates that genome editing using CRISPR technology will provide a promising pathway to generate disease-resistant citrus varieties.

  19. Fusarium-damaged kernels and deoxynivalenol in Fusarium-infected U.S. Winter Wheat

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Fusarium head blight (FHB) is a devastating disease that threatens wheat (Triticum aestivum L.) production in many areas worldwide. FHB infection results in Fusarium-damaged kernels (FDK) and deoxynivalenol (DON) that dramatically reduce grain yield and quality. More effective and accurate disease e...

  20. Fungus-Mediated Preferential Bioleaching of Waste Material Such as Fly - Ash as a Means of Producing Extracellular, Protein Capped, Fluorescent and Water Soluble Silica Nanoparticles

    PubMed Central

    Khan, Shadab Ali; Uddin, Imran; Moeez, Sana; Ahmad, Absar

    2014-01-01

    In this paper, we for the first time show the ability of the mesophilic fungus Fusarium oxysporum in the bioleaching of waste material such as Fly-ash for the extracellular production of highly crystalline and highly stable, protein capped, fluorescent and water soluble silica nanoparticles at ambient conditions. When the fungus Fusarium oxysporum is exposed to Fly-ash, it is capable of selectively leaching out silica nanoparticles of quasi-spherical morphology within 24 h of reaction. These silica nanoparticles have been completely characterized by UV-vis spectroscopy, Photoluminescence (PL), Transmission electron microscopy (TEM), X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR) and Energy dispersive analysis of X-rays (EDAX). PMID:25244567

  1. DNA Fingerprinting and Analysis of Population Structure in the Chestnut Blight Fungus, Cryphonectria Parasitica

    PubMed Central

    Milgroom, M. G.; Lipari, S. E.; Powell, W. A.

    1992-01-01

    We analyzed DNA fingerprints in the chestnut blight fungus, Cryphonectria parasitica, for stability, inheritance, linkage and variability in a natural population. DNA fingerprints resulting from hybridization with a dispersed moderately repetitive DNA sequence of C. parasitica in plasmid pMS5.1 hybridized to 6-17 restriction fragments per individual isolate. In a laboratory cross and from progeny from a single perithecium collected from a field population, the presence/absence of 11 fragments in the laboratory cross and 12 fragments in the field progeny set segregated in 1:1 ratios. Two fragments in each progeny set cosegregated; no other linkage was detected among the segregating fragments. Mutations, identified by missing bands, were detected for only one fragment in which 4 of 43 progeny lacked a band present in both parents; no novel fragments were detected in any progeny. All other fragments appeared to be stably inherited. Hybridization patterns did not change during vegetative growth or sporulation. However, fingerprint patterns of single conidial isolates of strains EP155 and EP67 were found to be heterogenous due to mutations that occurred during culturing in the laboratory since these strains were first isolated in 1976-1977. In a population sample of 39 C. parasitica isolates, we found 33 different fingerprint patterns with pMS5.1. Most isolates differed from all other isolates by the presence or absence of several fragments. Six fingerprint patterns each occurred twice. Isolates with identical fingerprints occurred in cankers on the same chestnut stems three times; isolates within the other three pairs were isolated from cankers more than 5 m apart. The null hypothesis of random mating in this population could not be rejected if the six putative clones were removed from the analysis. Thus, a rough estimate of the clonal fraction of this population is 6 in 39 isolates (15.4%). PMID:1353735

  2. Extracellular mycosynthesis of gold nanoparticles using Fusarium solani

    NASA Astrophysics Data System (ADS)

    Gopinath, K.; Arumugam, A.

    2014-08-01

    The development of eco-friendly methods for the synthesis of nanomaterial shape and size is an important area of research in the field of nanotechnology. The present investigation deals with the extracellular rapid biosynthesis of gold nanoparticles using Fusarium solani culture filtrate. The UV-vis spectra of the fungal culture filtrate medium containing gold ion showed peak at 527 nm corresponding to the plasmon absorbance of gold nanoparticles. FTIR spectra provide an evidence for the presence of heterocyclic compound in the culture filtrate, which increases the stability of the synthesized gold nanoparticles. The X-ray analysis respects the Bragg's law and confirmed the crystalline nature of the gold nanoparticles. AFM analysis showed the results of particle sizes (41 nm). Transmission electron microscopy (TEM) showed that the gold nanoparticles are spherical in shape with the size range from 20 to 50 nm. The use of F. solani will offer several advantages since it is considered as a non-human pathogenic organism. The fungus F. solani has a fast growth rate, rapid capacity of metallic ions reduction, NPs stabilization and facile and economical biomass handling. Extracellular biosynthesis of gold nanoparticles could be highly advantageous from the point of view of synthesis in large quantities, time consumption, eco-friendly, non-toxic and easy downstream processing.

  3. Extracellular peptidases of the cereal pathogen Fusarium graminearum

    PubMed Central

    Lowe, Rohan G. T.; McCorkelle, Owen; Bleackley, Mark; Collins, Christine; Faou, Pierre; Mathivanan, Suresh; Anderson, Marilyn

    2015-01-01

    The plant pathogenic fungus Fusarium graminearum (Fgr) creates economic and health risks in cereals agriculture. Fgr causes head blight (or scab) of wheat and stalk rot of corn, reducing yield, degrading grain quality, and polluting downstream food products with mycotoxins. Fungal plant pathogens must secrete proteases to access nutrition and to breakdown the structural protein component of the plant cell wall. Research into the proteolytic activity of Fgr is hindered by the complex nature of the suite of proteases secreted. We used a systems biology approach comprising genome analysis, transcriptomics and label-free quantitative proteomics to characterize the peptidases deployed by Fgr during growth. A combined analysis of published microarray transcriptome datasets revealed seven transcriptional groupings of peptidases based on in vitro growth, in planta growth, and sporulation behaviors. A high resolution mass spectrometry-based proteomics analysis defined the extracellular proteases secreted by F. graminearum. A meta-classification based on sequence characters and transcriptional/translational activity in planta and in vitro provides a platform to develop control strategies that target Fgr peptidases. PMID:26635820

  4. Optimization of Biological Synthesis of Silver Nanoparticles using Fusarium oxysporum

    PubMed Central

    Korbekandi, Hassan; Ashari, Zeynab; Iravani, Siavash; Abbasi, Sajjad

    2013-01-01

    Silver nanoparticles are increasingly used in various fields of biotechnology and applications in the medicine. Objectives of this study were optimization of production of silver nanoparticles using biotransformations by Fusarium oxysporum, and a further study on the location of nanoparticles synthesis in this microorganism. The reaction mixture contained the following ingredients (final concentrations): AgNO3 (1-10 mM) as the biotransformation substrate, biomass as the biocatalyst, glucose (560 mM) as the electron donor, and phosphate buffer (pH= 7, 100 mM). The samples were taken from the reaction mixtures at different times, and the absorbance (430 nm) of the colloidal suspensions of silver nanoparticles hydrosols was read freshly (without freezing) and immediately after dilution (1:40). SEM and TEM analyses were performed on selected samples. The presence of AgNO3 (0.1 mM) in the culture as enzyme inducer, and glucose (560 mM) as electron donor had positive effects on nanoparticle production. In SEM micrographs, silver nanoparticles were almost spherical, single (25-50 nm) or in aggregates (100 nm), attached to the surface of biomass. The reaction mixture was successfully optimized to increase the yield of silver nanoparticles production. More details of the location of nanoparticles production by this fungus were revealed, which support the hypothesis that silver nanoparticles are synthesized intracellularly and not extracellularly. PMID:24250635

  5. Pathogenicity of Conidiobolus coronatus and Fusarium solani in mouse models.

    PubMed

    Li, Yadi; Fang, Xiangang; Zhou, Xiaoqian; Geng, Suying; Wang, Yuxin; Yang, Xiumin

    2017-02-27

    To study the pathogenicity of Conidiobolus coronatus (C. coronatus) and Fusarium solani (F. solani) in animal models. Immunocompromised mice were treated with cyclophosphamide and prednisolone via intraperitoneal injection before and after inoculation. According to pathogenic characteristics of different fungi, C. coronatus was used to infect mice via intravenous inoculation, intraperitoneal inoculation, gastrointestinal infusion and intradermal inoculation methods. And F. solani was used to infect mice by inoculation via the abraded or normal skin. In the group of immunocompromised mice, C. coronatus was isolated from the lung tissues of one mouse on day 7 and another on day 10 respectively. The corresponding histopathology revealed infiltration of local inflammatory cells in the lung tissue. Pathogenic lesions were observed in all normal and immunocompromised mice infected with F. solani via abraded skin. The lesions in the immunocompromised mice were more severe and persisted longer than those in the normal mice. Moreover, hyphae were mostly observed in the histopathological examination and fungal culture from the immunocompromised mouse. The pathogenicity of C. coronatus was relatively weak as it did not induce local infections and did not disseminate the disease in immunocompetent and immunocompromised mice. Therefore, F. solani is a type of opportunistic pathogenic fungus, and abraded skin is one of the causative routes of infection.

  6. Gene expression in Fusarium graminearum grown on plant cell wall.

    PubMed

    Carapito, Raphaël; Hatsch, Didier; Vorwerk, Sonja; Petkovski, Elizabet; Jeltsch, Jean-Marc; Phalip, Vincent

    2008-05-01

    Fusarium graminearum is a phytopathogenic filamentous fungus attacking a wide range of plants including Humulus lupulus (hop). Transcriptional analysis of F. graminearum grown on minimal media containing hop cell wall or glucose as the sole carbon source was performed by applying a highly stringent method combining microarrays and a subtracted cDNA library. In addition to genes coding for various cell wall degrading enzymes (CWDE), several metabolic pathways were induced in response to the plant cell wall substrate. Many genes participating in these pathways are probably involved in cellular transport. But the most interesting was that all the genes composing the 4-aminobutyrate-shunt (GABA-shunt) were also up-regulated in the presence of plant cell wall material and were present in the cDNA library. This study provides a description of a part of the fungal gene expression profile when it is in contact with raw biological materials, and helps in understanding the plant cell wall degradation and the infection process.

  7. Extracellular peptidases of the cereal pathogen Fusarium graminearum.

    PubMed

    Lowe, Rohan G T; McCorkelle, Owen; Bleackley, Mark; Collins, Christine; Faou, Pierre; Mathivanan, Suresh; Anderson, Marilyn

    2015-01-01

    The plant pathogenic fungus Fusarium graminearum (Fgr) creates economic and health risks in cereals agriculture. Fgr causes head blight (or scab) of wheat and stalk rot of corn, reducing yield, degrading grain quality, and polluting downstream food products with mycotoxins. Fungal plant pathogens must secrete proteases to access nutrition and to breakdown the structural protein component of the plant cell wall. Research into the proteolytic activity of Fgr is hindered by the complex nature of the suite of proteases secreted. We used a systems biology approach comprising genome analysis, transcriptomics and label-free quantitative proteomics to characterize the peptidases deployed by Fgr during growth. A combined analysis of published microarray transcriptome datasets revealed seven transcriptional groupings of peptidases based on in vitro growth, in planta growth, and sporulation behaviors. A high resolution mass spectrometry-based proteomics analysis defined the extracellular proteases secreted by F. graminearum. A meta-classification based on sequence characters and transcriptional/translational activity in planta and in vitro provides a platform to develop control strategies that target Fgr peptidases.

  8. Occurrence of fungi and fungus-like organisms in the Horodnianka River in the vicinity of Białystok, Poland.

    PubMed

    Kiziewicz, Bozena; Zdrojkowska, Ewa; Gajo, Bernadetta; Godlewska, Anna; Muszyńska, Elzbieta; Mazalska, Bozenna

    2011-01-01

    Studies of fungi and fungus- like organisms in the northeastern Poland have mainly concentrated on running waters in the vicinity of Białystok, including the Horodnianka River. The main objective was to investigate biodiversity of fungi and fungus-like organisms which take part in decomposition of organic matter commonly found in inland waters. To obtain a complete picture of species composition of fungi and fungus-like organisms in running waters we decided to explore representative sites of the Horodnianka River such as Olmonty, Hryniewicze and Horodniany with close localization of landfill. Fungal species were isolated using baiting technique. Baits of onion skin (Alium cepa), hemp-seeds (Cannabis sativa), impregnated cellophane and snake skin (Natrix natrix) were applied to isolate fungi from water of the Horodnianka River. The fungal community consists of 26 species, 10 species of fungi belonging to class Chytridiomycetes (3), anamorphic fungi (6), and Zygomycetes (1). 16 species belong to fungus-like organisms from class Oomycetes. Most of the recognized species have already been found in other running waters. From all the examined habitats the fungi belonging to 26 species of 18 genera Achlya, Alternaria, Aphanomyces, Aspergillus, Catenophlyctis, Dictyuchus, Fusarium, Karlingia, Lagenidium, Leptomitus, Olpidiopsis, Penicillium, Phlyctochytrium, Pythium, Saprolegnia, Scoliognia, Thraustotheca and Zoophagus were obtained. Certain fungal species like Aphanomyces laevis, Fusarium aqueductum, F. moniliforme, F. oxysporum, Leptomitus lacteus, Saprolegnia feax and S. parasitica were found at all the study sites. Among fungi potentially pathogenic and allergogenic for humans the genera Alternaria, Aspergillus, Fusarium, Lagenidium and Penicillium have already been described. However, the species Lagenidium giganteum and Achlya androgyna are new in the fungal biota of Poland. The greatest number of fungal species occurred in Olmonty (24), the smallest in Horodniany

  9. Tissue-specific and pathogen-inducible expression of a fusion protein containing a Fusarium-specific antibody and a fungal chitinase protects wheat against Fusarium pathogens and mycotoxins.

    PubMed

    Cheng, Wei; Li, He-Ping; Zhang, Jing-Bo; Du, Hong-Jie; Wei, Qi-Yong; Huang, Tao; Yang, Peng; Kong, Xian-Wei; Liao, Yu-Cai

    2015-06-01

    Fusarium head blight (FHB) in wheat and other small grain cereals is a globally devastating disease caused by toxigenic Fusarium pathogens. Controlling FHB is a challenge because germplasm that is naturally resistant against these pathogens is inadequate. Current control measures rely on fungicides. Here, an antibody fusion comprised of the Fusarium spp.-specific recombinant antibody gene CWP2 derived from chicken, and the endochitinase gene Ech42 from the biocontrol fungus Trichoderma atroviride was introduced into the elite wheat cultivar Zhengmai9023 by particle bombardment. Expression of this fusion gene was regulated by the lemma/palea-specific promoter Lem2 derived from barley; its expression was confirmed as lemma/palea-specific in transgenic wheat. Single-floret inoculation of independent transgenic wheat lines of the T3 to T6 generations revealed significant resistance (type II) to fungal spreading, and natural infection assays in the field showed significant resistance (type I) to initial infection. Gas chromatography-mass spectrometry analysis revealed marked reduction of mycotoxins in the grains of the transgenic wheat lines. Progenies of crosses between the transgenic lines and the FHB-susceptible cultivar Huamai13 also showed significantly enhanced FHB resistance. Quantitative real-time PCR analysis revealed that the tissue-specific expression of the antibody fusion was induced by salicylic acid drenching and induced to a greater extent by F. graminearum infection. Histochemical analysis showed substantial restriction of mycelial growth in the lemma tissues of the transgenic plants. Thus, the combined tissue-specific and pathogen-inducible expression of this Fusarium-specific antibody fusion can effectively protect wheat against Fusarium pathogens and reduce mycotoxin content in grain.

  10. Host-induced silencing of Fusarium culmorum genes protects wheat from infection

    PubMed Central

    Chen, Wanxin; Kastner, Christine; Nowara, Daniela; Oliveira-Garcia, Ely; Rutten, Twan; Zhao, Yusheng; Deising, Holger B.; Kumlehn, Jochen; Schweizer, Patrick

    2016-01-01

    Plants producing antisense or double-stranded RNA molecules that target specific genes of eukaryotic pests or pathogens can become protected from their attack. This beneficial effect was also reported for plant–fungus interactions and is believed to reflect uptake of the RNAs by the fungus via an as yet unknown mechanism, followed by target gene silencing. Here we report that wheat plants pre-infected with Barley stripe mosaic virus (BSMV) strains containing antisense sequences against target genes of the Fusarium head blight (FHB) fungus F. culmorum caused a reduction of corresponding transcript levels in the pathogen and reduced disease symptoms. Stable transgenic wheat plants carrying an RNAi hairpin construct against the β-1, 3-glucan synthase gene FcGls1 of F. culmorum or a triple combination of FcGls1 with two additional, pre-tested target genes also showed enhanced FHB resistance in leaf and spike inoculation assays under greenhouse and near-field conditions, respectively. Microscopic evaluation of F. culmorum development in plants transiently or stably expressing FcGls1 silencing constructs revealed aberrant, swollen fungal hyphae, indicating severe hyphal cell wall defects. The results lead us to propose host-induced gene silencing (HIGS) as a plant protection approach that may also be applicable to highly FHB-susceptible wheat genotypes. PMID:27540093

  11. Fusarium Infection in Lung Transplant Patients

    PubMed Central

    Carneiro, Herman A.; Coleman, Jeffrey J.; Restrepo, Alejandro; Mylonakis, Eleftherios

    2013-01-01

    Fusarium is a fungal pathogen of immunosuppressed lung transplant patients associated with a high mortality in those with severe and persistent neutropenia. The principle portal of entry for Fusarium species is the airways, and lung involvement almost always occurs among lung transplant patients with disseminated infection. In these patients, the immunoprotective mechanisms of the transplanted lungs are impaired, and they are, therefore, more vulnerable to Fusarium infection. As a result, fusariosis occurs in up to 32% of lung transplant patients. We studied fusariosis in 6 patients following lung transplantation who were treated at Massachusetts General Hospital during an 8-year period and reviewed 3 published cases in the literature. Cases were identified by the microbiology laboratory and through discharge summaries. Patients presented with dyspnea, fever, nonproductive cough, hemoptysis, and headache. Blood tests showed elevated white blood cell counts with granulocytosis and elevated inflammatory markers. Cultures of Fusarium were isolated from bronchoalveolar lavage, blood, and sputum specimens. Treatments included amphotericin B, liposomal amphotericin B, caspofungin, voriconazole, and posaconazole, either alone or in combination. Lung involvement occurred in all patients with disseminated disease and it was associated with a poor outcome. The mortality rate in this group of patients was high (67%), and of those who survived, 1 patient was treated with a combination of amphotericin B and voriconazole, 1 patient with amphotericin B, and 1 patient with posaconazole. Recommended empirical treatment includes voriconazole, amphotericin B or liposomal amphotericin B first-line, and posaconazole for refractory disease. High-dose amphotericin B is recommended for treatment of most cases of fusariosis. The echinocandins (for example, caspofungin, micafungin, anidulafungin) are generally avoided because Fusarium species have intrinsic resistance to them. Treatment

  12. Novel insights into the genomic basis of citrus canker based on the genome sequences of two strains of Xanthomonas fuscans subsp. aurantifolii

    PubMed Central

    2010-01-01

    Background Citrus canker is a disease that has severe economic impact on the citrus industry worldwide. There are three types of canker, called A, B, and C. The three types have different phenotypes and affect different citrus species. The causative agent for type A is Xanthomonas citri subsp. citri, whose genome sequence was made available in 2002. Xanthomonas fuscans subsp. aurantifolii strain B causes canker B and Xanthomonas fuscans subsp. aurantifolii strain C causes canker C. Results We have sequenced the genomes of strains B and C to draft status. We have compared their genomic content to X. citri subsp. citri and to other Xanthomonas genomes, with special emphasis on type III secreted effector repertoires. In addition to pthA, already known to be present in all three citrus canker strains, two additional effector genes, xopE3 and xopAI, are also present in all three strains and are both located on the same putative genomic island. These two effector genes, along with one other effector-like gene in the same region, are thus good candidates for being pathogenicity factors on citrus. Numerous gene content differences also exist between the three cankers strains, which can be correlated with their different virulence and host range. Particular attention was placed on the analysis of genes involved in biofilm formation and quorum sensing, type IV secretion, flagellum synthesis and motility, lipopolysacharide synthesis, and on the gene xacPNP, which codes for a natriuretic protein. Conclusion We have uncovered numerous commonalities and differences in gene content between the genomes of the pathogenic agents causing citrus canker A, B, and C and other Xanthomonas genomes. Molecular genetics can now be employed to determine the role of these genes in plant-microbe interactions. The gained knowledge will be instrumental for improving citrus canker control. PMID:20388224

  13. The HEX1 gene of Fusarium graminearum is required for fungal asexual reproduction and pathogenesis and for efficient viral RNA accumulation of Fusarium graminearum virus 1.

    PubMed

    Son, Moonil; Lee, Kyung-Mi; Yu, Jisuk; Kang, Minji; Park, Jin Man; Kwon, Sun-Jung; Kim, Kook-Hyung

    2013-09-01

    The accumulation of viral RNA depends on many host cellular factors. The hexagonal peroxisome (Hex1) protein is a fungal protein that is highly expressed when the DK21 strain of Fusarium graminearum virus 1 (FgV1) infects its host, and Hex1 affects the accumulation of FgV1 RNA. The Hex1 protein is the major constituent of the Woronin body (WB), which is a peroxisome-derived electron-dense core organelle that seals the septal pore in response to hyphal wounding. To clarify the role of Hex1 and the WB in the relationship between FgV1 and Fusarium graminearum, we generated targeted gene deletion and overexpression mutants. Although neither HEX1 gene deletion nor overexpression substantially affected vegetative growth, both changes reduced the production of asexual spores and reduced virulence on wheat spikelets in the absence of FgV1 infection. However, the vegetative growth of deletion and overexpression mutants was increased and decreased, respectively, upon FgV1 infection compared to that of an FgV1-infected wild-type isolate. Viral RNA accumulation was significantly decreased in deletion mutants but was significantly increased in overexpression mutants compared to the viral RNA accumulation in the virus-infected wild-type control. Overall, these data indicate that the HEX1 gene plays a direct role in the asexual reproduction and virulence of F. graminearum and facilitates viral RNA accumulation in the FgV1-infected host fungus.

  14. Selection of Small Synthetic Antimicrobial Peptides Inhibiting Xanthomonas citri subsp. citri Causing Citrus Canker

    PubMed Central

    Choi, Jeahyuk; Park, Euiho; Lee, Se-Weon; Hyun, Jae-Wook; Baek, Kwang-Hyun

    2017-01-01

    Citrus canker disease decreases the fruit quality and yield significantly, furthermore, emerging of streptomycin-resistant pathogens threatens the citrus industry seriously because of a lack of proper control agents. Small synthetic antimicrobial peptides (AMPs) could be a promising alternative. Fourteen hexapeptides were selected by using positional scanning of synthetic peptide combinatorial libraries. Each hexapeptide showed different antimicrobial spectrum against Bacillus, Pseudomonas, Xanthomonas, and Candida species. Intriguingly, BHC10 showed bactericidal activity exclusively on Xanthomonas citri subsp. citri (Xcc), while BHC7 was none-active exclusively against two Pseudomonas spp. at concentration of 100 μg/ml suggesting potential selectivity constrained in hexapeptide frame. Three hexapeptides, BHC02, 06 and 11, showed bactericidal activities against various Xcc strains at concentration of 10 μg/ml. When they were co-infiltrated with pathogens into citrus leaves the disease progress was suppressed significantly. Further study would be needed to confirm the actual disease control capacity of the selected hexapeptides. PMID:28167892

  15. Lonsdalea quercina subsp. populi subsp. nov., isolated from bark canker of poplar trees.

    PubMed

    Tóth, Tímea; Lakatos, Tamás; Koltay, András

    2013-06-01

    Seven Gram-negative bacterial strains were isolated from oozing bark canker of poplar (Populus × euramericana) trees in Hungary. They showed high (>98.3%) 16S rRNA gene sequence similarity to Lonsdalea quercina; however, they differed from this species in several phenotypic characteristics. Multilocus sequence analysis based on three housekeeping genes (gyrB, atpD and infB) revealed, and DNA-DNA hybridization analysis confirmed, that this group of bacterial strains forms a distinct lineage within the species Lonsdalea quercina. A detailed study of phenotypic and physiological characteristics confirmed the separation of isolates from poplars from other subspecies of L. quercina; therefore, a novel subspecies, Lonsdalea quercina subsp. populi, type strain NY060(T) (=DSM 25466(T)=NCAIM B 02483(T)), is proposed.

  16. Extracellular polysaccharides of a bacterium associated with a fungal canker disease of Eucalyptus sp.

    PubMed

    Yang, Byung Yun; Ding, Qiong; Montgomery, Rex

    2002-04-17

    Extracellular polysaccharides (EPSs) produced by an Erwinia sp associated with a fungal canker disease of Eucalyptus were fractionated into one polysaccharide that was identified with that produced by Erwinia chrysanthemi strains SR260, Ech1, and Ech9, and the other distinctively different from any other EPS produced by E. chrysanthemi strains so far studied. Their structures were determined using a combination of chemical and physical techniques including methylation analysis, low pressure gel-filtration, and anion-exchange chromatographies, high-pH anion-exchange chromatography, mass spectrometry and 1D and 2D 1H NMR spectroscopy. The new polysaccharide, identified as EPS Teranera, has the following structure: [structure: see text] The molecular weights of the polysaccharides range from 3.2-6.2 x 10(5) and their hydrodynamic properties are those of polydisperse, polyanionic biopolymers with pseudoplastic, non-thixotropic flow characteristics in aqueous solutions.

  17. Adaptive expression of host cell wall degrading enzymes in fungal disease: an example from Fusarium root rot of medicinal Coleus.

    PubMed

    Bhattacharya, A

    2013-12-15

    Quantity of extracellular proteins and activities two cell wall degrading enzymes pectinase and cellulase were determined in the culture filtrate of Fusarium solani, the causal organism of root rot of Coleus forskohlii. Substitution of carbon source in the medium with either pectin or carboxymethyl cellulose led to the increased production of extracellular proteins by the fungus. Pectinase and cellulase activity in the culture filtrate was detected only when the growth medium contained substituted carbon source in the form of pectin and CMC, respectively. Pectinase activity was highest after 5 days incubation and then decreased gradually with time but cellulase activity showed a steady time dependent increase. In vitro virulence study showed the requirement of both the enzymes for complete expression of rot symptoms on Coleus plants. Thus the present study established the adaptive, substrate dependent expression of the two enzymes by the fungus and also their involvement in the root rot disease of Coleus forskohlii.

  18. Diversity of the Fusarium complex on French maize

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Ear rot caused by Fusarium species is a major threat to maize production worldwide, causing yield reduction and poor grain quality. In addition, various species of the genus Fusarium can produce mycotoxins, which accumulate in the grain. The distribution and predominance of the different Fusarium sp...

  19. Fusarium stalk blight and rot in sugar beet

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Fusarium stalk blight of sugar beet can cause reductions or complete loss of seed production. The causal agent is Fusarium oxysporum. In addition, Fusarium solani has been demonstrated to cause a rot of sugar beet seed stalk, and other species have been reported associated with sugar beet fruit, but...

  20. Canker Sores

    MedlinePlus

    ... Birth Control Family HealthInfants and Toddlers Kids and Teens Pregnancy and Childbirth Women Men SeniorsIn The NewsYour Health ... Birth Control Family HealthInfants and Toddlers Kids and Teens Pregnancy and Childbirth Women Men SeniorsIn The NewsYour Health ...

  1. Canker Sores

    MedlinePlus

    ... and Vision Leadership Executive Committee Board of Trustees Governance Past Presidents Staff/Contact History Awards Our Partners ... tell the difference? A: The location is a good clue. Your doctor may recommend performing culture testing ...

  2. Canker sore

    MedlinePlus

    ... which can irritate the area more.) Apply a mixture of half hydrogen peroxide and half water directly ... times a day. Rinse your mouth with a mixture of half Milk of Magnesia and half Benadryl ...

  3. Canker Sore

    MedlinePlus

    ... Policy Notice of Privacy Practices Notice of Nondiscrimination Advertising Mayo Clinic is a not-for-profit organization and proceeds from Web advertising help support our mission. Mayo Clinic does not ...

  4. Canker Sores

    MedlinePlus

    ... SLS is a foaming agent found in most toothpastes and mouthwashes. Finally, not getting the right nutrition, ... you brush your teeth . Brush and rinse with toothpastes and mouthwashes that don't contain sodium lauryl ...

  5. Temperature effects on the interactions of sugar beet Fusarium yellows caused by Fusarium oxysporum f. sp. betae

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Fusarium yellows of sugar beet (Beta vulgaris L.), caused by Fusarium oxysporum f. sp. betae, causes a significant reduction in root yield, sucrose percentage, and juice purity. The environmental or agronomic factors that contribute to development and severity of Fusarium yellows have not been desc...

  6. Comparative genomic analysis of duplicated homoeologous regions involved in the resistance of Brassica napus to stem canker.

    PubMed

    Fopa Fomeju, Berline; Falentin, Cyril; Lassalle, Gilles; Manzanares-Dauleux, Maria J; Delourme, Régine

    2015-01-01

    All crop species are current or ancient polyploids. Following whole genome duplication, structural and functional modifications result in differential gene content or regulation in the duplicated regions, which can play a fundamental role in the diversification of genes underlying complex traits. We have investigated this issue in Brassica napus, a species with a highly duplicated genome, with the aim of studying the structural and functional organization of duplicated regions involved in quantitative resistance to stem canker, a disease caused by the fungal pathogen Leptosphaeria maculans. Genome-wide association analysis on two oilseed rape panels confirmed that duplicated regions of ancestral blocks E, J, R, U, and W were involved in resistance to stem canker. The structural analysis of the duplicated genomic regions showed a higher gene density on the A genome than on the C genome and a better collinearity between homoeologous regions than paralogous regions, as overall in the whole B. napus genome. The three ancestral sub-genomes were involved in the resistance to stem canker and the fractionation profile of the duplicated regions corresponded to what was expected from results on the B. napus progenitors. About 60% of the genes identified in these duplicated regions were single-copy genes while less than 5% were retained in all the duplicated copies of a given ancestral block. Genes retained in several copies were mainly involved in response to stress, signaling, or transcription regulation. Genes with resistance-associated markers were mainly retained in more than two copies. These results suggested that some genes underlying quantitative resistance to stem canker might be duplicated genes. Genes with a hydrolase activity that were retained in one copy or R-like genes might also account for resistance in some regions. Further analyses need to be conducted to indicate to what extent duplicated genes contribute to the expression of the resistance phenotype.

  7. Assessing quantitative resistance against Leptosphaeria maculans (phoma stem canker) in Brassica napus (oilseed rape) in young plants.

    PubMed

    Huang, Yong-Ju; Qi, Aiming; King, Graham J; Fitt, Bruce D L

    2014-01-01

    Quantitative resistance against Leptosphaeria maculans in Brassica napus is difficult to assess in young plants due to the long period of symptomless growth of the pathogen from the appearance of leaf lesions to the appearance of canker symptoms on the stem. By using doubled haploid (DH) lines A30 (susceptible) and C119 (with quantitative resistance), quantitative resistance against L. maculans was assessed in young plants in controlled environments at two stages: stage 1, growth of the pathogen along leaf veins/petioles towards the stem by leaf lamina inoculation; stage 2, growth in stem tissues to produce stem canker symptoms by leaf petiole inoculation. Two types of inoculum (ascospores; conidia) and three assessment methods (extent of visible necrosis; symptomless pathogen growth visualised using the GFP reporter gene; amount of pathogen DNA quantified by PCR) were used. In stage 1 assessments, significant differences were observed between lines A30 and C119 in area of leaf lesions, distance grown along veins/petioles assessed by visible necrosis or by viewing GFP and amount of L. maculans DNA in leaf petioles. In stage 2 assessments, significant differences were observed between lines A30 and C119 in severity of stem canker and amount of L. maculans DNA in stem tissues. GFP-labelled L. maculans spread more quickly from the stem cortex to the stem pith in A30 than in C119. Stem canker symptoms were produced more rapidly by using ascospore inoculum than by using conidial inoculum. These results suggest that quantitative resistance against L. maculans in B. napus can be assessed in young plants in controlled conditions. Development of methods to phenotype quantitative resistance against plant pathogens in young plants in controlled environments will help identification of stable quantitative resistance for control of crop diseases.

  8. Assessing Quantitative Resistance against Leptosphaeria maculans (Phoma Stem Canker) in Brassica napus (Oilseed Rape) in Young Plants

    PubMed Central

    Huang, Yong-Ju; Qi, Aiming; King, Graham J.; Fitt, Bruce D. L.

    2014-01-01

    Quantitative resistance against Leptosphaeria maculans in Brassica napus is difficult to assess in young plants due to the long period of symptomless growth of the pathogen from the appearance of leaf lesions to the appearance of canker symptoms on the stem. By using doubled haploid (DH) lines A30 (susceptible) and C119 (with quantitative resistance), quantitative resistance against L. maculans was assessed in young plants in controlled environments at two stages: stage 1, growth of the pathogen along leaf veins/petioles towards the stem by leaf lamina inoculation; stage 2, growth in stem tissues to produce stem canker symptoms by leaf petiole inoculation. Two types of inoculum (ascospores; conidia) and three assessment methods (extent of visible necrosis; symptomless pathogen growth visualised using the GFP reporter gene; amount of pathogen DNA quantified by PCR) were used. In stage 1 assessments, significant differences were observed between lines A30 and C119 in area of leaf lesions, distance grown along veins/petioles assessed by visible necrosis or by viewing GFP and amount of L. maculans DNA in leaf petioles. In stage 2 assessments, significant differences were observed between lines A30 and C119 in severity of stem canker and amount of L. maculans DNA in stem tissues. GFP-labelled L. maculans spread more quickly from the stem cortex to the stem pith in A30 than in C119. Stem canker symptoms were produced more rapidly by using ascospore inoculum than by using conidial inoculum. These results suggest that quantitative resistance against L. maculans in B. napus can be assessed in young plants in controlled conditions. Development of methods to phenotype quantitative resistance against plant pathogens in young plants in controlled environments will help identification of stable quantitative resistance for control of crop diseases. PMID:24454767

  9. Effect of X-irradiation on Citrus Canker Pathogen Xanthomonas citri subsp. citri of Satsuma Mandarin Fruits

    PubMed Central

    Song, Min-A; Park, Jae Sin; Kim, Ki Deok; Jeun, Yong Chull

    2015-01-01

    Citrus canker caused by Xanthomonas citri subsp. citri (Xcc) is one of the most important bacterial diseases of citrus. Because citrus canker is not found in many countries including European Union and Australia, Xcc is strictly regulated in order to prevent its spread. In this study, the effects of X-irradiation on Xcc growth either in the suspension or on the surface of citrus fruits were investigated. The suspension containing 1×107 cfu/ml of Xcc was irradiated with different absorbed doses of X-irradiation ranging from 50 to 400 Gy. The results showed that Xcc was fully dead at 400 Gy of X-irradiation. To determine the effect of X-irradiation on quarantine, the Xcc-inoculated citrus fruits were irradiated with different X-ray doses at which Xcc was completely inhibited by an irradiation dose of 250 Gy. The D10 value for Xcc on citrus fruits was found to be 97 Gy, indicating the possibility of direct application on citrus quarantine without any side sterilizer. Beside, presence of Xcc on the surface of asymptomatic citrus fruits obtained from citrus canker-infected orchards was noted. It indicated that the exporting citrus fruits need any treatment so that Xcc on the citrus fruits should be completely eliminated. Based on these results, ionizing radiation can be considered as an alternative method of eradicating Xcc for export of citrus fruits. PMID:26672670

  10. Inhibitory effects of antimicrobial agents against Fusarium species.

    PubMed

    Kawakami, Hideaki; Inuzuka, Hiroko; Hori, Nobuhide; Takahashi, Nobumichi; Ishida, Kyoko; Mochizuki, Kiyofumi; Ohkusu, Kiyofumi; Muraosa, Yasunori; Watanabe, Akira; Kamei, Katsuhiko

    2015-08-01

    We investigated the inhibitory effects of antibacterial, biocidal, and antifungal agents against Fusarium spp. Seven Fusarium spp: four F. falciforme (Fusarium solani species complex), one Fusarium spp, one Fusarium spp. (Fusarium incarnatum-equiseti species complex), and one F. napiforme (Gibberella fujikuroi species complex), isolated from eyes with fungal keratitis were used in this study. Their susceptibility to antibacterial agents: flomoxef, imipenem, gatifloxacin, levofloxacin, moxifloxacin, gentamicin, tobramycin, and Tobracin® (contained 3,000 μg/ml of tobramycin and 25 μg/ml of benzalkonium chloride (BAK), a biocidal agent: BAK, and antifungal agents: amphotericin B, pimaricin (natamycin), fluconazole, itraconazole, miconazole, voriconazole, and micafungin, was determined by broth microdilution tests. The half-maximal inhibitory concentration (IC50), 100% inhibitory concentration (IC100), and minimum inhibitory concentration (MIC) against the Fusarium isolates were determined. BAK had the highest activity against the Fusarium spp. except for the antifungal agents. Three fluoroquinolones and two aminoglycosides had inhibitory effects against the Fusarium spp. at relatively high concentrations. Tobracin® had a higher inhibitory effect against Fusarium spp. than tobramycin alone. Amphotericin B had the highest inhibitory effect against the Fusarium spp, although it had different degrees of activity against each isolate. Our findings showed that fluoroquinolones, aminoglycosides, and BAK had some degree of inhibitory effect against the seven Fusarium isolates, although these agents had considerably lower effect than amphotericin B. However, the inhibitory effects of amphotericin B against the Fusarium spp. varied for the different isolates. Further studies for more effective medications against Fusarium, such as different combinations of antibacterial, biocidal, and antifungal agents are needed.

  11. Feed Refusal Factors in Pure Cultures of Fusarium roseum ”graminearum”

    PubMed Central

    Kotsonis, Frank N.; Smalley, Eugene B.; Ellison, Robert A.; Gale, Carol M.

    1975-01-01

    Isolations from 1972 Wisconsin feed refusal corn yielded predominantly cultures of Fusarium roseum ”graminearum.” With one possible exception, none of the selected isolates of this fungus induced emesis in pigeons, whereas six of nine isolates produced feed refusal responses in all test animals. A single isolate of F. roseum ”equiseti” also induced a severe refusal response and possibly slight emesis. None of the other fungi isolated from this corn (F. moniliforme, Acremoniella atra) or controls caused either emesis or feed refusal. Zearalenone was detected in all isolates and was shown to be partially responsible for refusal activity. The remaining activity was ascribed to one or more nonvolatile, neutral, relatively polar molecules. T-2 toxin, although not detected in these isolates, was shown to have dramatic refusal activity in rats. PMID:1237267

  12. The production of β-glucosidases by Fusarium proliferatum NBRC109045 isolated from Vietnamese forest

    PubMed Central

    2012-01-01

    Fusarium proliferatum NBRC109045 is a filamentous fungus isolated from Vietnamese forest due to high production of β-glucosidases. Production of the enzyme was studied on varied carbon source based mediums. The highest activity was obtained in medium containing 1% corn stover + 1% wheat bran (3.31 ± 0.14 U/ml). It is interesting to note that glucose (0.69 ± 0.02 U/ml) gave higher activity and just followed by cellobiose among the di- and mono-saccharides, which is generally regarded as a universal repressor of hydrolases. We improved the zymogram method to prove that in response to various carbon sources, F. proliferatum could express various β-glucosidases. One of the β-glucosidases produced by F. proliferatum growing in corn stover + wheat bran based medium was partially purified and proved to have high catalytic ability. PMID:22974424

  13. The effect of nanosilver on pigments production by Fusarium culmorum (W. G. Sm.) Sacc.

    PubMed

    Kasprowicz, Marek J; Gorczyca, Anna; Frandsen, Rasmus J N

    2013-01-01

    A disk-diffusion method experiment assessed the impact of nanosilver on production of secondary metabolites (pigments) by the Fusarium culmorum fungus. Nanosilver colloidal particles in water have been obtained by the use of a method based on high voltage electric arcs between silver electrodes. The silver nanoparticles size in colloid ranged between 15 and 100 nm and 7, 35 and 70 ppm concentration. Nanosilver modifies the metabolism of the researched F. culmorum strain. Coming into contact with nanosilver colloids induces more intensive mycelia pigmentation correlated with nanosilver concentration levels. The performed analysis of metabolites indicates that under the influence of nanosilver fungi biosynthesise aurofusarin more intensively and the conversion of rubrofusarin to aurofusarin is intensified as compared to the control culture. Under the influence of nanosilver F. culmorum intensively biosynthesises an unidentified dye which shares structural features with aurofusarin but which is not produced by fungi in standard cultures.

  14. [Development and relations of Fusarium culmorum and Pseudomonas fluorescens in soil].

    PubMed

    Strunnikova, O K; Shakhnazarova, V Iu; Vishnevskaia, N A; Chebotar', V K; Tikhonovich, I A

    2007-01-01

    The development of Fusarium culmorum and Pseudomonas fluorescens in soil, and the relations between them, were studied using membrane filters containing the fungus, the bacterium, or both microorganisms; the filters were incubated in soil. F. culmorum was identified by indirect immunofluorescence: the GUS-labeled strain was used to visualize P. fluorescens. It was found that F. culmorum introduced in soil can develop as a saprotroph, with the formation of mycelium, macroconidia, and a small amount of chlamydospores. Introduction of glucose and cellulose resulted in increased density of the F. culmorum mycelium and macroconidia. P. fluorescens suppressed development of F. culmorum mycelium in soil but stimulated formation of fungal chlamydospores. Decreased mycelial density in the presence of P. fluorescens was more pronounced in unsupplemented soil and less pronounced when glucose or cellulose was intiodaced. F. culmorum had no significant effect on P. fluorescens growth in soil.

  15. Occurrence of Fusarium verticillioides and Fusarium musae on banana fruits marketed in Hungary.

    PubMed

    Molnár, Orsolya; Bartók, Tibor; Szécsi, Árpád

    2015-06-01

    Fusarium strains were isolated from rotten banana fruit imported into Hungary from some African and some Neotropical countries. The strains were identified using morphological features, 2-benzoxazolinone tolerance, translation elongation factor (EF-1α) sequences and inter simple sequence repeat (ISSR) analysis. All strains from Africa proved to be F. verticillioides whereas the strains from the Neotropics are Fusarium musae. According to the PCR proof and the fumonisin toxin measurement F. musae strains cannot produce any fumonisins (FB1-4).

  16. Natural occurrence of Fusarium species, fumonisin production by toxigenic strains, and concentrations of fumonisins B1, and B2 in conventional and organic maize grown in Spain.

    PubMed

    Ariño, Agustín; Juan, Teresa; Estopañan, Gloria; González-Cabo, José F

    2007-01-01

    Sixty samples of corn from both conventional and organic farms were tested for internal fungal contamination. Molds were identified to genus, and those belonging to the genus Fusarium were identified to species. Twenty isolates of Fusarium verticillioides were tested with a high-performance liquid chromatography-naphthalene dicarboxaldehyde-fluorescence method for their ability to produce fumonisins B1 and B2. The internal fungal infection in organic maize (63.20%) was significantly higher than that in conventional maize (40.27%) (P < 0.05). However, the distribution of fungal genera indicated a significantly higher prevalence of Fusarium in conventional (34.93%) than in organic (18.15%) maize, making Fusarium the predominant fungus in conventional maize. This difference in mold distribution between organic and conventional maize was attributed to the difference in cultivation system. The dominant Fusarium species in both conventional and organic samples was F. verticillioides. There were no significant differences in the ability of 20 selected isolates of F. verticillioides to produce fumonisins on conventional or organic corn. Up to 13.3% of the conventional corn samples contained fumonisins B1 and B2 at mean concentrations of 43 and 22 ng/g, respectively. Organic corn samples had somewhat lower levels of contamination: 35 ng/g fumonisin B1 and 19 ng/g fumonisin B2 (P > 0.05). The organic farming system, with well-balanced crop rotation, tillage, and compost fertilization, produced corn that was less likely to be contaminated with Fusarium species, although no significant difference in fumonisin concentrations was found between the two types of contaminated corn.

  17. Antifungal Attributes of Lactobacillus plantarum MYS6 against Fumonisin Producing Fusarium proliferatum Associated with Poultry Feeds.

    PubMed

    Deepthi, B V; Poornachandra Rao, K; Chennapa, G; Naik, M K; Chandrashekara, K T; Sreenivasa, M Y

    2016-01-01

    Fumonisins, being common in occurrence in maize-based feeds, pose a great threat to animal and human health. The present study is aimed at determining the antifungal activity of Lactobacillus plantarum MYS6 against a fumonisin producing fungus, Fusarium proliferatum MYS9. The isolate was subjected to standard tests for determining its probiotic attributes and antifungal properties. L. plantarum MYS6 thrived well at pH 3.0 and 6.0, and exhibited strong resistance up to 3% bile. The isolate showed a high degree of cell surface hydrophobicity corresponding to its strong adhesion to chicken crop epithelial cells. Co-inoculation with the fungus on modified de Man Rogosa Sharpe medium revealed the inhibitory effect of L. plantarum MYS6 on fungal growth and biomass. Observation using scanning electron microscopy showed distortion of hyphal structures, swollen tips and disrupted conidia. Conidia germination inhibition assay restrained germination and showed deformed hyphae. The bioprotective feature of the isolate was evident by the inhibition of fungal development in maize-kernel treated with the cell free supernatant of L. plantarum MYS6. Both the isolate and its extracellular metabolites lowered fumonisin content in feed model up to 0.505 mg/Kg of feed and 0.3125 mg/Kg of feed respectively when compared to the level of 0.870 mg/Kg of feed in control. The major antifungal compounds produced by the isolate were 10-Octadecenoic acid, methyl ester; palmitic acid, methyl ester; heptadecanoic acid, 16-methyl ester; stearic acid and lauric acid. L. plantarum MYS6 reduced 61.7% of fumonisin possibly by a binding mechanism. These findings suggest the application of L. plantarum MYS6 as an efficient probiotic additive and biocontrol agent in feed used in poultry industry. Additionally, the antifungal metabolites pose a conspicuous inhibition of Fusarium growth and fumonisin production.

  18. Antifungal Attributes of Lactobacillus plantarum MYS6 against Fumonisin Producing Fusarium proliferatum Associated with Poultry Feeds

    PubMed Central

    Deepthi, B. V.; Poornachandra Rao, K.; Chennapa, G.; Naik, M. K.; Chandrashekara, K. T.; Sreenivasa, M. Y.

    2016-01-01

    Fumonisins, being common in occurrence in maize-based feeds, pose a great threat to animal and human health. The present study is aimed at determining the antifungal activity of Lactobacillus plantarum MYS6 against a fumonisin producing fungus, Fusarium proliferatum MYS9. The isolate was subjected to standard tests for determining its probiotic attributes and antifungal properties. L. plantarum MYS6 thrived well at pH 3.0 and 6.0, and exhibited strong resistance up to 3% bile. The isolate showed a high degree of cell surface hydrophobicity corresponding to its strong adhesion to chicken crop epithelial cells. Co-inoculation with the fungus on modified de Man Rogosa Sharpe medium revealed the inhibitory effect of L. plantarum MYS6 on fungal growth and biomass. Observation using scanning electron microscopy showed distortion of hyphal structures, swollen tips and disrupted conidia. Conidia germination inhibition assay restrained germination and showed deformed hyphae. The bioprotective feature of the isolate was evident by the inhibition of fungal development in maize-kernel treated with the cell free supernatant of L. plantarum MYS6. Both the isolate and its extracellular metabolites lowered fumonisin content in feed model up to 0.505 mg/Kg of feed and 0.3125 mg/Kg of feed respectively when compared to the level of 0.870 mg/Kg of feed in control. The major antifungal compounds produced by the isolate were 10-Octadecenoic acid, methyl ester; palmitic acid, methyl ester; heptadecanoic acid, 16-methyl ester; stearic acid and lauric acid. L. plantarum MYS6 reduced 61.7% of fumonisin possibly by a binding mechanism. These findings suggest the application of L. plantarum MYS6 as an efficient probiotic additive and biocontrol agent in feed used in poultry industry. Additionally, the antifungal metabolites pose a conspicuous inhibition of Fusarium growth and fumonisin production. PMID:27285317

  19. Genome-Based Selection and Characterization of Fusarium circinatum-Specific Sequences

    PubMed Central

    Maphosa, Mkhululi N.; Steenkamp, Emma T.; Wingfield, Brenda D.

    2016-01-01

    Fusarium circinatum is an important pathogen of pine trees and its management in the commercial forestry environment relies largely on early detection, particularly in seedling nurseries. The fact that the entire genome of this pathogen is available opens new avenues for the development of diagnostic tools for this fungus. In this study we identified open reading frames (ORFs) unique to F. circinatum and determined that they were specific to the pathogen. The ORF identification process involved bioinformatics-based screening of all the putative F. circinatum ORFs against public databases. This was followed by functional characterization of ORFs found to be unique to F. circinatum. We used PCR- and hybridization-based approaches to confirm the presence of selected unique genes in different strains of F. circinatum and their absence from other Fusarium species for which genome sequence data are not yet available. These included species that are closely related to F. circinatum as well as those that are commonly encountered in the forestry environment. Thirty-six ORFs were identified as potentially unique to F. circinatum. Nineteen of these encode proteins with known domains while the other 17 encode proteins of unknown function. The results of our PCR analyses and hybridization assays showed that three of the selected genes were present in all of the strains of F. circinatum tested and absent from the other Fusarium species screened. These data thus indicate that the selected genes are common and unique to F. circinatum. These genes thus could be good candidates for use in rapid, in-the-field diagnostic assays specific to F. circinatum. Our study further demonstrates how genome sequence information can be mined for the identification of new diagnostic markers for the detection of plant pathogens. PMID:26888868

  20. Two Novel Relative Double-Stranded RNA Mycoviruses Infecting Fusarium poae Strain SX63

    PubMed Central

    Wang, Luan; Zhang, Jingze; Zhang, Hailong; Qiu, Dewen; Guo, Lihua

    2016-01-01

    Two novel double-stranded RNA (dsRNA) mycoviruses, termed Fusarium poae dsRNA virus 2 (FpV2) and Fusarium poae dsRNA virus 3 (FpV3), were isolated from the plant pathogenic fungus, Fusarium poae strain SX63, and molecularly characterized. FpV2 and FpV3, with respective genome sequences of 9518 and 9419 base pairs (bps), are both predicted to contain two discontinuous open reading frames (ORFs), ORF1 and ORF2. A hypothetical polypeptide (P1) and a RNA-dependent RNA polymerase (RdRp) are encoded by ORF1 and ORF2, respectively. Phytoreo_S7 domain (pfam07236) homologs were detected downstream of the RdRp domain (RdRp_4; pfam02123) of the ORF2-coded proteins of both FpV2 and FpV3. The same shifty heptamers (GGAAAAC) were both found immediately before the stop codon UAG of ORF1 in FpV2 and FpV3, which could mediate programmed –1 ribosomal frameshifting (–1 PRF). Phylogenetic analysis based on RdRp sequences clearly place FpV2 and FpV3 in a taxonomically unassigned dsRNA mycovirus group. Together, with a comparison of genome organization, a new taxonomic family termed Fusagraviridae is proposed to be created to include FpV2- and FpV3-related dsRNA mycoviruses, within which FpV2 and FpV3 would represent two distinct virus species. PMID:27144564

  1. Contamination of Bananas with Beauvericin and Fusaric Acid Produced by Fusarium oxysporum f. sp. cubense

    PubMed Central

    Kuang, Ruibin; Yang, Qiaosong; Hu, Chunhua; Sheng, Ou; Zhang, Sheng; Ma, Lijun; Wei, Yuerong; Yang, Jing; Liu, Siwen; Biswas, Manosh Kumar; Viljoen, Altus; Yi, Ganjun

    2013-01-01

    Background Fusarium wilt, caused by the fungal pathogen Fusarium oxysporum f. sp. cubense (Foc), is one of the most destructive diseases of banana. Toxins produced by Foc have been proposed to play an important role during the pathogenic process. The objectives of this study were to investigate the contamination of banana with toxins produced by Foc, and to elucidate their role in pathogenesis. Methodology/Principal Findings Twenty isolates of Foc representing races 1 and 4 were isolated from diseased bananas in five Chinese provinces. Two toxins were consistently associated with Foc, fusaric acid (FA) and beauvericin (BEA). Cytotoxicity of the two toxins on banana protoplast was determined using the Alamar Blue assay. The virulence of 20 Foc isolates was further tested by inoculating tissue culture banana plantlets, and the contents of toxins determined in banana roots, pseudostems and leaves. Virulence of Foc isolates correlated well with toxin deposition in the host plant. To determine the natural occurrence of the two toxins in banana plants with Fusarium wilt symptoms, samples were collected before harvest from the pseudostems, fruit and leaves from 10 Pisang Awak ‘Guangfen #1’ and 10 Cavendish ‘Brazilian’ plants. Fusaric acid and BEA were detected in all the tissues, including the fruits. Conclusions/Signficance The current study provides the first investigation of toxins produced by Foc in banana. The toxins produced by Foc, and their levels of contamination of banana fruits, however, were too low to be of concern to human and animal health. Rather, these toxins appear to contribute to the pathogenicity of the fungus during infection of banana plants. PMID:23922960

  2. The Sch9 Kinase Regulates Conidium Size, Stress Responses, and Pathogenesis in Fusarium graminearum

    PubMed Central

    Zhou, Xiaoying; Wang, Yulin; Xu, Jin-Rong

    2014-01-01

    Fusarium head blight caused by Fusarium graminearum is an important disease of wheat and barley worldwide. In a previous study on functional characterization of the F. graminearum kinome, one protein kinase gene important for virulence is orthologous to SCH9 that is functionally related to the cAMP-PKA and TOR pathways in the budding yeast. In this study, we further characterized the functions of FgSCH9 in F. graminearum and its ortholog in Magnaporthe oryzae. The ΔFgsch9 mutant was slightly reduced in growth rate but significantly reduced in conidiation, DON production, and virulence on wheat heads and corn silks. It had increased tolerance to elevated temperatures but became hypersensitive to oxidative, hyperosmotic, cell wall, and membrane stresses. The ΔFgsch9 deletion also had conidium morphology defects and produced smaller conidia. These results suggest that FgSCH9 is important for stress responses, DON production, conidiogenesis, and pathogenesis in F. graminearum. In the rice blast fungus Magnaporthe oryzae, the ΔMosch9 mutant also was defective in conidiogenesis and pathogenesis. Interestingly, it also produced smaller conidia and appressoria. Taken together, our data indicate that the SCH9 kinase gene may have a conserved role in regulating conidium size and plant infection in phytopathogenic ascomycetes. PMID:25144230

  3. A fungal symbiont of plant-roots modulates mycotoxin gene expression in the pathogen Fusarium sambucinum.

    PubMed

    Ismail, Youssef; McCormick, Susan; Hijri, Mohamed

    2011-03-24

    Fusarium trichothecenes are fungal toxins that cause disease on infected plants and, more importantly, health problems for humans and animals that consume infected fruits or vegetables. Unfortunately, there are few methods for controlling mycotoxin production by fungal pathogens. In this study, we isolated and characterized sixteen Fusarium strains from naturally infected potato plants in the field. Pathogenicity tests were carried out in the greenhouse to evaluate the virulence of the strains on potato plants as well as their trichothecene production capacity, and the most aggressive strain was selected for further studies. This strain, identified as F. sambucinum, was used to determine if trichothecene gene expression was affected by the symbiotic Arbuscular mycorrhizal fungus (AMF) Glomus irregulare. AMF form symbioses with plant roots, in particular by improving their mineral nutrient uptake and protecting plants against soil-borne pathogens. We found that that G. irregulare significantly inhibits F. sambucinum growth. We also found, using RT-PCR assays to assess the relative expression of trichothecene genes, that in the presence of the AMF G. irregulare, F. sambucinum genes TRI5 and TRI6 were up-regulated, while TRI4, TRI13 and TRI101 were down-regulated. We conclude that AMF can modulate mycotoxin gene expression by a plant fungal pathogen. This previously undescribed effect may be an important mechanism for biological control and has fascinating implications for advancing our knowledge of plant-microbe interactions and controlling plant pathogens.

  4. Involvement of Fungal Pectin Methylesterase Activity in the Interaction Between Fusarium graminearum and Wheat.

    PubMed

    Sella, Luca; Castiglioni, Carla; Paccanaro, Maria Chiara; Janni, Michela; Schäfer, Wilhelm; D'Ovidio, Renato; Favaron, Francesco

    2016-04-01

    The genome of Fusarium graminearum, the causal agent of Fusarium head blight of wheat, contains two putative pectin methylesterase (PME)-encoding genes. However, when grown in liquid culture containing pectin, F. graminearum produces only a single PME, which was purified and identified. Its encoding gene, expressed during wheat spike infection, was disrupted by targeted homologous recombination. Two Δpme mutant strains lacked PME activity but were still able to grow on highly methyl-esterified pectin even though their polygalacturonase (PG) activity showed a reduced capacity to depolymerize this substrate. The enzymatic assays performed with purified F. graminearum PG and PME demonstrated an increase in PG activity in the presence of PME on highly methyl-esterified pectin. The virulence of the mutant strains was tested on Triticum aestivum and Triticum durum spikes, and a significant reduction in the percentage of symptomatic spikelets was observed between 7 and 12 days postinfection compared with wild type, demonstrating that the F. graminearum PME contributes to fungal virulence on wheat by promoting spike colonization in the initial and middle stages of infection. In contrast, transgenic wheat plants with increased levels of pectin methyl esterification did not show any increase in resistance to the Δpme mutant, indicating that the infectivity of the fungus relies only to a certain degree on pectin degradation.

  5. [Clusters of Fusarium solani infection in juvenile captive born Caretta caretta sea turtles].

    PubMed

    Garcia-Hartmann, M; Hennequin, C; Catteau, S; Béatini, C; Blanc, V

    2017-03-01

    Various yeasts and filamentous fungi are described as the cause of infection in sea turtles. Among them, Fusarium solani is responsible both for superficial and invasive infection in weakened adults (capture, stranding), and wild nest contamination, causing massive losses during hatching. We illustrate the pathogenicity of this fungus in sea turtles, through our experience with the species Caretta caretta (loggerhead turtle) and its reproduction, which was obtained for the first time in 2010 at the marine park Marineland, Antibes and renewed in 2011 and 2013. The first generation (6 viable newborns e.g. 0.9% of the nest) was severely affected by an infectious agent causing skin and multifocal organ lesions. Microbiological samples allowed to establish F. solani as the etiological agent. Antifungal therapy with posaconazole cured 2 (33%) of the brood. Epidemiological investigations, infection control and hygiene measures as well as diagnosis criteria, preemptive and curative treatment procedures allowed better prevention and cure and finally higher survival rates in subsequent broods, in 2011 and 2013 (80 viable newborns e.g. 6.6% of the nest and 50% survival rate). F. solani appears as a major threat for the successful reproduction of sea turtles in the wild. As observed, this threat is also of concern during captive breeding. The conditions of transmission and pathogenicity of Fusarium spp. in these animals are discussed in light of the literature cases that occurred in adult sea turtles and in wild nests, and of our breeding experience.

  6. The Membrane Mucin Msb2 Regulates Invasive Growth and Plant Infection in Fusarium oxysporum[W

    PubMed Central

    Pérez-Nadales, Elena; Di Pietro, Antonio

    2011-01-01

    Fungal pathogenicity in plants requires a conserved mitogen-activated protein kinase (MAPK) cascade homologous to the yeast filamentous growth pathway. How this signaling cascade is activated during infection remains poorly understood. In the soil-borne vascular wilt fungus Fusarium oxysporum, the orthologous MAPK Fmk1 (Fusarium MAPK1) is essential for root penetration and pathogenicity in tomato (Solanum lycopersicum) plants. Here, we show that Msb2, a highly glycosylated transmembrane protein, is required for surface-induced phosphorylation of Fmk1 and contributes to a subset of Fmk1-regulated functions related to invasive growth and virulence. Mutants lacking Msb2 share characteristic phenotypes with the Δfmk1 mutant, including defects in cellophane invasion, penetration of the root surface, and induction of vascular wilt symptoms in tomato plants. In contrast with Δfmk1, Δmsb2 mutants were hypersensitive to cell wall targeting compounds, a phenotype that was exacerbated in a Δmsb2 Δfmk1 double mutant. These results suggest that the membrane mucin Msb2 promotes invasive growth and plant infection upstream of Fmk1 while contributing to cell integrity through a distinct pathway. PMID:21441438

  7. New tricks of an old enemy: isolates of Fusarium graminearum produce a type A trichothecene mycotoxin.

    PubMed

    Varga, Elisabeth; Wiesenberger, Gerlinde; Hametner, Christian; Ward, Todd J; Dong, Yanhong; Schöfbeck, Denise; McCormick, Susan; Broz, Karen; Stückler, Romana; Schuhmacher, Rainer; Krska, Rudolf; Kistler, H Corby; Berthiller, Franz; Adam, Gerhard

    2015-08-01

    The ubiquitous filamentous fungus Fusarium graminearum causes the important disease Fusarium head blight on various species of cereals, leading to contamination of grains with mycotoxins. In a survey of F. graminearum (sensu stricto) on wheat in North America several novel strains were isolated, which produced none of the known trichothecene mycotoxins despite causing normal disease symptoms. In rice cultures, a new trichothecene mycotoxin (named NX-2) was characterized by liquid chromatography-tandem mass spectrometry. Nuclear magnetic resonance measurements identified NX-2 as 3α-acetoxy-7α,15-dihydroxy-12,13-epoxytrichothec-9-ene. Compared with the well-known 3-acetyl-deoxynivalenol (3-ADON), it lacks the keto group at C-8 and hence is a type A trichothecene. Wheat ears inoculated with the isolated strains revealed a 10-fold higher contamination with its deacetylated form, named NX-3, (up to 540 mg kg(-1) ) compared with NX-2. The toxicities of the novel mycotoxins were evaluated utilizing two in vitro translation assays and the alga Chlamydomonas reinhardtii. NX-3 inhibits protein biosynthesis to almost the same extent as the prominent mycotoxin deoxynivalenol, while NX-2 is far less toxic, similar to 3-ADON. Genetic analysis revealed a different TRI1 allele in the N-isolates, which was verified to be responsible for the difference in hydroxylation at C-8.

  8. Fusarium and other opportunistic hyaline fungi

    Technology Transfer Automated Retrieval System (TEKTRAN)

    This chapter focuses on those fungi that grow in tissue in the form of hyaline or lightly colored septate hyphae. These fungi include Fusarium and other hyaline fungi. Disease caused by hyaline fungi is referred to as hyalohyphomycosis. Hyaline fungi described in this chapter include the anamorphic,...

  9. Production of fusaric acid by Fusarium species.

    PubMed Central

    Bacon, C W; Porter, J K; Norred, W P; Leslie, J F

    1996-01-01

    Fusaric acid is a mycotoxin with low to moderate toxicity, which is of concern since it might be synergistic with other cooccurring mycotoxins. Fusaric acid is widespread on corn and corn-based food and feeds and is frequently found in grain, where Fusarium spp. are also isolated. We surveyed 78 strains of Fusarium moniliforme, F. crookwellense, F. subglutinans, F. sambucinum, F. napiforme, F. heterosporum, F. oxysporum, F. solani, and F. proliferatum for their ability to produce fusaric acid. Strains in Fusarium section Liseola also were assigned to mating population of the Gibberella fujikuroi species complex. The fungi could be divided into three classes, low (< 100 micrograms/g), moderate (100 to 500 micrograms/g), and high (> 500 micrograms/g), based on the amounts of this mycotoxin produced in culture on autoclaved corn. Strains of mating populations C from rice consistently produced moderate to high concentrations of fusaric acid. Two isolates, one each from mating populations C and D, produced fusaric acid in excess of 1,000 micrograms/g of corn. No isolates of any of the Fusarium species examined were negative for the production of fusaric acid on autoclaved corn. PMID:8899996

  10. Investigating Spore killer of Fusarium verticillioides

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Maize is one of the most important crops in the world. Fusarium verticillioides may colonize maize as an endophyte or as a pathogen, causing disease at any life stage of the plant. During growth on maize, F. verticillioides can synthesis a number of mycotoxins including fumonisins, which have been l...

  11. Volatile organic compounds: a potential direct long-distance mechanism for antagonistic action of Fusarium oxysporum strain MSA 35.

    PubMed

    Minerdi, Daniela; Bossi, Simone; Gullino, Maria Lodovica; Garibaldi, Angelo

    2009-04-01

    Fusarium oxysporum MSA35 [wild-type (WT) strain] is an antagonistic Fusarium that lives in association with a consortium of bacteria belonging to the genera Serratia, Achromobacter, Bacillus and Stenotrophomonas in an Italian soil suppressive to Fusarium wilt. Typing experiments and virulence tests provided evidence that the F. oxysporum isolate when cured of the bacterial symbionts [the cured (CU) form], is pathogenic, causing wilt symptoms identical to those caused by F. oxysporum f. sp. lactucae. Here, we demonstrate that small volatile organic compounds (VOCs) emitted from the WT strain negatively influence the mycelial growth of different formae speciales of F. oxysporum. Furthermore, these VOCs repress gene expression of two putative virulence genes in F. oxysporum lactucae strain Fuslat10, a fungus against which the WT strain MSA 35 has antagonistic activity. The VOC profile of the WT and CU fungus shows different compositions. Sesquiterpenes, mainly caryophyllene, were present in the headspace only of WT MSA 35. No sesquiterpenes were found in the volatiles of ectosymbiotic Serratia sp. strain DM1 and Achromobacter sp. strain MM1. Bacterial volatiles had no effects on the growth of the different ff. spp. of F. oxysporum examined. Hyphae grownwithVOCfrom WT F. oxysporum f. sp. lactucae strain MSA 35 were hydrophobic whereas those grown without VOCs were not, suggesting a correlation between the presence of volatiles in the atmosphere and the phenotype of the mycelium. This is the first report of VOC production by antagonistic F. oxysporum MSA35 and their effects on pathogenic F. oxysporum. The results obtained in this work led us to propose a new potential direct long-distance mechanism for antagonism by F. oxysporum MSA 35 mediated by VOCs. Antagonism could be the consequence of both reduction of pathogen mycelial growth and inhibition of pathogen virulence gene expression.

  12. Identification of Ina proteins from Fusarium acuminatum

    NASA Astrophysics Data System (ADS)

    Scheel, Jan Frederik; Kunert, Anna Theresa; Pöschl, Ulrich; Fröhlich-Nowoisky, Janine

    2015-04-01

    Freezing of water above -36° C is based on ice nucleation activity (INA) mediated by ice nucleators (IN) which can be of various origins. Beside mineral IN, biological particles are a potentially important source of atmospheric IN. The best-known biological IN are common plant-associated bacteria. The IN activity of these bacteria is induced by a surface protein on the outer cell membrane, which is fully characterized. In contrast, much less is known about the nature of fungal IN. The fungal genus Fusarium is widely spread throughout the earth. It belongs to the Ascomycota and is one of the most severe fungal pathogens. It can affect a variety of organisms from plants to animals including humans. INA of Fusarium was already described about 30 years ago and INA of Fusarium as well as other fungal genera is assumed to be mediated by proteins or at least to contain a proteinaceous compound. Although many efforts were made the precise INA machinery of Fusarium and other fungal species including the proteins and their corresponding genes remain unidentified. In this study preparations from living fungal samples of F. acuminatum were fractionated by liquid chromatography and IN active fractions were identified by freezing assays. SDS-page and de novo sequencing by mass spectrometry were used to identify the primary structure of the protein. Preliminary results show that the INA protein of F. acuminatum is contained in the early size exclusion chromatography fractions indicating a high molecular size. Moreover we could identify a single protein band from IN active fractions at 130-145 kDa corresponding to sizes of IN proteins from bacterial species. To our knowledge this is for the first time an isolation of a single protein from in vivo samples, which can be assigned as IN active from Fusarium.

  13. De novo genome assembly of Geosmithia morbida, the causal agent of thousand cankers disease

    PubMed Central

    Westbrook, Anthony; Woeste, Keith

    2016-01-01

    Geosmithia morbida is a filamentous ascomycete that causes thousand cankers disease in the eastern black walnut tree. This pathogen is commonly found in the western U.S.; however, recently the disease was also detected in several eastern states where the black walnut lumber industry is concentrated. G. morbida is one of two known phytopathogens within the genus Geosmithia, and it is vectored into the host tree via the walnut twig beetle. We present the first de novo draft genome of G. morbida. It is 26.5 Mbp in length and contains less than 1% repetitive elements. The genome possesses an estimated 6,273 genes, 277 of which are predicted to encode proteins with unknown functions. Approximately 31.5% of the proteins in G. morbida are homologous to proteins involved in pathogenicity, and 5.6% of the proteins contain signal peptides that indicate these proteins are secreted. Several studies have investigated the evolution of pathogenicity in pathogens of agricultural crops; forest fungal pathogens are often neglected because research efforts are focused on food crops. G. morbida is one of the few tree phytopathogens to be sequenced, assembled and annotated. The first draft genome of G. morbida serves as a valuable tool for comprehending the underlying molecular and evolutionary mechanisms behind pathogenesis within the Geosmithia genus. PMID:27168971

  14. The Xanthomonas axonopodis pv. citri flagellum is required for mature biofilm and canker development.

    PubMed

    Malamud, Florencia; Torres, Pablo S; Roeschlin, Roxana; Rigano, Luciano A; Enrique, Ramón; Bonomi, Hernán R; Castagnaro, Atilio P; Marano, María Rosa; Vojnov, Adrián A

    2011-03-01

    Xanthomonas axonopodis pv. citri (Xac) is the causative agent of citrus canker. This bacterium develops a characteristic biofilm on both biotic and abiotic surfaces. To evaluate the participation of the single flagellum of Xac in biofilm formation, mutants in the fliC (flagellin) and the flgE (hook) genes were generated. Swimming motility, assessed on 0.25 % agar plates, was markedly reduced in fliC and flgE mutants. However, the fliC and flgE mutants exhibited a flagellar-independent surface translocation on 0.5 % agar plates. Mutation of either the rpfF or the rpfC gene, which both encode proteins involved in cell-cell signalling mediated by diffusible signal factor (DSF), led to a reduction in both flagellar-dependent and flagellar-independent surface translocation, indicating a regulatory role for DSF in both types of motility. Confocal laser scanning microscopy of biofilms produced in static culture demonstrated that the flagellum is also involved in the formation of mushroom-shaped structures and water channels, and in the dispersion of biofilms. The presence of the flagellum was required for mature biofilm development on lemon leaf surfaces. The absence of flagellin produced a slight reduction in Xac pathogenicity and this reduction was more severe when the complete flagellum structure was absent.

  15. Description of Acinetobacter populi sp. nov. isolated from symptomatic bark of Populus x euramericana canker.

    PubMed

    Li, Yong; Chang, Jupu; Guo, Li-min; Wang, Hai-Ming; Xie, Shou-jiang; Piao, Chun-gen; He, Wei

    2015-12-01

    Five Gram-negative, non-motile, rod-shaped bacterial strains were isolated from cankers of Populus x euramericana collected from different locations in Puyang city, Henan Province, China. The five strains were characterized by nutritional and physiological testing and DNA sequence analysis. Haemolysis was not observed on agar media supplemented with sheep erythrocytes. The strains could be distinguished from members of most species of the genus Acinetobacter by their inability to assimilate L-arginine and benzoate. The five strains formed a single branch in phylogenetic trees based on 16S rRNA, gyrB and rpoB individual gene sequence analysis,indicating that they all belonged to a single taxon within the genus Acinetobacter. DNA-DNA hybridization results indicated that the five isolates represented to a single species that was separate from Acinetobacter puyangensis. On the basis of the phenotypic, genotypic and phylogenetic characteristics, the five strains are considered to represent a novel species of the genus Acinetobacter, for which the name Acinetobacter populi sp. nov. is proposed. The typestrain of A. populi sp. nov. is PBJ7T (CFCC 11170T=KCTC 42272T).

  16. Distribution of disease symptoms and mycotoxins in maize ears infected by Fusarium culmorum and Fusarium graminearum.

    PubMed

    Oldenburg, Elisabeth; Ellner, Frank

    2015-08-01

    Red ear rot an important disease of maize cultivated in Europe is caused by toxigenic Fusarium species like Fusarium graminearum and Fusarium culmorum. To get detailed information on the time course of the infection process leading to the accumulation of Fusarium mycotoxins in maize ears, a field study was conducted over 2 years with two maize varieties, which were inoculated with F. culmorum or F. graminearum isolates at the stage of female flowering. Every fortnight after inoculation, infection and contamination progress in the ears was followed by visually evaluating disease signs and analysing Fusarium toxin concentrations in the infected ear tissues. In principle, infection and mycotoxin distribution were similar in respect of pathogens, varieties, and years. External infection symptoms showing some small pale or brown-marbled kernels with dark brown pedicels were mainly seen at the ear tip, whereas internal infection symptoms on the rachis were much more pronounced and spread in the upper half showing greyish brownish or pink discoloration of the pith. Well correlated with disease symptoms, a top-down gradient from high to low toxin levels within the ear with considerably higher concentrations in the rachis compared with the kernels was observed. It is suggested that both Fusarium pathogens primarily infect the rachis from the tip toward the bottom, whereas the kernels are subsequently infected via the rachillae connected to the rachis. A special focus on the pronounced disease symptoms visible in the rachis may be an approach to improve the evaluation of maize-genotype susceptibility against red ear rot pathogens. It has to be underlined that the accumulation of Fusarium mycotoxins in the rachis greatly accelerated 6 weeks after inoculation; therefore, highest contamination risk is indicated for feedstuffs containing large amounts of rachis (e.g., corn cob mix), especially when cut late in growing season.

  17. Fungus mediated biosynthesis and characterization of zinc oxide nanorods

    NASA Astrophysics Data System (ADS)

    Venkatesh, K. S.; Palani, N. S.; Krishnamoorthi, S. R.; Thirumal, V.; Ilangovan, R.

    2013-06-01

    Recently nanomaterials have been synthesized through biological approach due to its biocompatibility, inexpensive, eco friendly and it offers easiest experimental protocol and so on. ZnO can be potentially used in various applications. This present study reports the fungus mediated extra-cellular bio synthesis of ZnO nanorods using Fusarium Solani. The dried powder was calcined at 350°C for 1 hour in air. The thermal property of the as synthesized ZnO nanopowder was analyzed through Thermo gravimetric /Differential Thermo gravimetric (TGA / DTG) analysis. The structural and morphological properties of the calcined ZnO nanopowder were studied by XRD and SEM analysis respectively. X ray diffraction result revealed that a peak located at 2θ = 36.2° with (101) plane confirms the presence of Zinc oxide with Hexagonal crystal system. The morphology of the calcined ZnO powder was analyzed by Scanning Electron Microscopy and it clearly indicates the presence of ZnO nanorods. The diameter of the nanorods is in the range of 60 to 95 nm.

  18. Fate of Fusarium Toxins during the Malting Process.

    PubMed

    Habler, Katharina; Hofer, Katharina; Geißinger, Cajetan; Schüler, Jan; Hückelhoven, Ralph; Hess, Michael; Gastl, Martina; Rychlik, Michael

    2016-02-17

    Little is known about the fate of Fusarium mycotoxins during the barley malting process. To determine the fungal DNA and mycotoxin concentrations during malting, we used barley grain harvested from field plots that we had inoculated with Fusarium species that produce type A or type B trichothecenes or enniatins. Using a recently developed multimycotoxin liquid chromatography-tandem mass stable isotope dilution method, we identified Fusarium-species-specific behaviors of mycotoxins in grain and malt extracts and compared toxin concentrations to amounts of fungal DNA in the same samples. In particular, the type B trichothecenes and Fusarium culmorum DNA contents were increased dramatically up to 5400% after kilning. By contrast, the concentrations of type A trichothecenes and Fusarium sporotrichioides DNA decreased during the malting process. These data suggest that specific Fusarium species that contaminate the raw grain material might have different impacts on malt quality.

  19. Identification of an Endophytic Antifungal Bacterial Strain Isolated from the Rubber Tree and Its Application in the Biological Control of Banana Fusarium Wilt.

    PubMed

    Tan, Deguan; Fu, Lili; Han, Bingyin; Sun, Xuepiao; Zheng, Peng; Zhang, Jiaming

    2015-01-01

    Banana Fusarium wilt (also known as Panama disease) is one of the most disastrous plant diseases. Effective control methods are still under exploring. The endophytic bacterial strain ITBB B5-1 was isolated from the rubber tree, and identified as Serratia marcescens by morphological, biochemical, and phylogenetic analyses. This strain exhibited a high potential for biological control against the banana Fusarium disease. Visual agar plate assay showed that ITBB B5-1 restricted the mycelial growth of the pathogenic fungus Fusarium oxysporum f. sp. cubense race 4 (FOC4). Microscopic observation revealed that the cell wall of the FOC4 mycelium close to the co-cultured bacterium was partially decomposed, and the conidial formation was prohibited. The inhibition ratio of the culture fluid of ITBB B5-1 against the pathogenic fungus was 95.4% as estimated by tip culture assay. Chitinase and glucanase activity was detected in the culture fluid, and the highest activity was obtained at Day 2 and Day 3 of incubation for chitinase and glucanase, respectively. The filtrated cell-free culture fluid degraded the cell wall of FOC4 mycelium. These results indicated that chitinase and glucanase were involved in the antifungal mechanism of ITBB B5-1. The potted banana plants that were inoculated with ITBB B5-1 before infection with FOC4 showed 78.7% reduction in the disease severity index in the green house experiments. In the field trials, ITBB B5-1 showed a control effect of approximately 70.0% against the disease. Therefore, the endophytic bacterial strain ITBB B5-1 could be applied in the biological control of banana Fusarium wilt.

  20. Identification of an Endophytic Antifungal Bacterial Strain Isolated from the Rubber Tree and Its Application in the Biological Control of Banana Fusarium Wilt

    PubMed Central

    Sun, Xuepiao; Zheng, Peng; Zhang, Jiaming

    2015-01-01

    Banana Fusarium wilt (also known as Panama disease) is one of the most disastrous plant diseases. Effective control methods are still under exploring. The endophytic bacterial strain ITBB B5-1 was isolated from the rubber tree, and identified as Serratia marcescens by morphological, biochemical, and phylogenetic analyses. This strain exhibited a high potential for biological control against the banana Fusarium disease. Visual agar plate assay showed that ITBB B5-1 restricted the mycelial growth of the pathogenic fungus Fusarium oxysporum f. sp. cubense race 4 (FOC4). Microscopic observation revealed that the cell wall of the FOC4 mycelium close to the co-cultured bacterium was partially decomposed, and the conidial formation was prohibited. The inhibition ratio of the culture fluid of ITBB B5-1 against the pathogenic fungus was 95.4% as estimated by tip culture assay. Chitinase and glucanase activity was detected in the culture fluid, and the highest activity was obtained at Day 2 and Day 3 of incubation for chitinase and glucanase, respectively. The filtrated cell-free culture fluid degraded the cell wall of FOC4 mycelium. These results indicated that chitinase and glucanase were involved in the antifungal mechanism of ITBB B5-1. The potted banana plants that were inoculated with ITBB B5-1 before infection with FOC4 showed 78.7% reduction in the disease severity index in the green house experiments. In the field trials, ITBB B5-1 showed a control effect of approximately 70.0% against the disease. Therefore, the endophytic bacterial strain ITBB B5-1 could be applied in the biological control of banana Fusarium wilt. PMID:26133557

  1. Structure of Oxalacetate Acetylhydrolase, a Virulence Factor of the Chestnut Blight Fungus

    SciTech Connect

    Chen, Chen; Sun, Qihong; Narayanan, Buvaneswari; Nuss, Donald L.; Herzberg, Osnat

    2010-11-15

    Oxalacetate acetylhydrolase (OAH), a member of the phosphoenolpyruvate mutase/isocitrate lyase superfamily, catalyzes the hydrolysis of oxalacetate to oxalic acid and acetate. This study shows that knock-out of the oah gene in Cryphonectria parasitica, the chestnut blight fungus, reduces the ability of the fungus to form cankers on chestnut trees, suggesting that OAH plays a key role in virulence. OAH was produced in Escherichia coli and purified, and its catalytic rates were determined. Oxalacetate is the main OAH substrate, but the enzyme also acts as a lyase of (2R,3S)-dimethyl malate with {approx}1000-fold lower efficacy. The crystal structure of OAH was determined alone, in complex with a mechanism-based inhibitor, 3,3-difluorooxalacetate (DFOA), and in complex with the reaction product, oxalate, to a resolution limit of 1.30, 1.55, and 1.65 {angstrom}, respectively. OAH assembles into a dimer of dimers with each subunit exhibiting an ({alpha}/{beta})8 barrel fold and each pair swapping the 8th {alpha}-helix. An active site 'gating loop' exhibits conformational disorder in the ligand-free structure. To obtain the structures of the OAH {center_dot} ligand complexes, the ligand-free OAH crystals were soaked briefly with DFOA or oxalacetate. DFOA binding leads to ordering of the gating loop in a conformation that sequesters the ligand from the solvent. DFOA binds in a gem-diol form analogous to the oxalacetate intermediate/transition state. Oxalate binds in a planar conformation, but the gating loop is largely disordered. Comparison between the OAH structure and that of the closely related enzyme, 2,3-dimethylmalate lyase, suggests potential determinants of substrate preference.

  2. Hyperkeratotic Warty Skin Lesion of Foot Caused by Fusarium oxysporum

    PubMed Central

    Kaur, Ravinder; Maheshwari, Megha

    2013-01-01

    Fusarium species are common soil-inhabiting organisms and plant pathogens. Human infections are usually precipitated by local or systemic predisposing factors, and disseminated infection is associated with impaired immune responses. Skin infections caused by Fusarium spp. include keratitis, onychomycosis, mycetoma, painful discrete erythematous nodules. Hyperkeratotic skin lesions caused by Fusarium spp. are, however, rarely reported. We report a case of hyperkeratotic verrucous warty skin lesion in the foot of a 50-year-old immunocompetent male, farmer by occupation. PMID:23716829

  3. Heterologous expression of transaldolase gene Tal from Saccharomyces cerevisiae in Fusarium oxysporum for enhanced bioethanol production.

    PubMed

    Fan, Jin-Xia; Yang, Xiao-Xue; Song, Jin-Zhu; Huang, Xiao-Mei; Cheng, Zhong-Xiang; Yao, Lin; Juba, Olivia S; Liang, Qing; Yang, Qian; Odeph, Margaret; Sun, Yan; Wang, Yun

    2011-08-01

    The filamentous fungus Fusarium oxysporum is known for its ability to ferment xylose-producing ethanol. However, efficiency of xylose utilization and ethanol yield was low. In this study, the transaldolase gene from Saccharomyces cerevisiae has been successfully expressed in F. oxysporum by an Agrobacterium tumefaciens-mediated transformation method. The enzymatic activity of the recombinant fungus (cs28pCAM-Sctal4) was 0.195 times higher than that of the wild-type strain (cs28). The recombinant strain also exhibited a 28.83% increase in ethanol yield on xylose media compared to the parental strain. Enhanced ethanol production and a reduction in the biomass were observed during xylose fermentation. Ethanol yield from rice straw by simultaneous saccharification and fermentation with cs28pCAM-Sctal4 was 0.25 g g⁻¹ of rice straw. The transgenic strain of F. oxysporum cs28pCAM-Sctal4 might therefore have potential applications in industrial bioenergy production.

  4. Metabolic Engineering of Fusarium oxysporum to Improve Its Ethanol-Producing Capability

    PubMed Central

    Anasontzis, George E.; Kourtoglou, Elisavet; Villas-Boâs, Silas G.; Hatzinikolaou, Dimitris G.; Christakopoulos, Paul

    2016-01-01

    Fusarium oxysporum is one of the few filamentous fungi capable of fermenting ethanol directly from plant cell wall biomass. It has the enzymatic toolbox necessary to break down biomass to its monosaccharides and, under anaerobic and microaerobic conditions, ferments them to ethanol. Although these traits could enable its use in consolidated processes and thus bypass some of the bottlenecks encountered in ethanol production from lignocellulosic material when Saccharomyces cerevisiae is used—namely its inability to degrade lignocellulose and to consume pentoses—two major disadvantages of F. oxysporum compared to the yeast—its low growth rate and low ethanol productivity—hinder the further development of this process. We had previously identified phosphoglucomutase and transaldolase, two major enzymes of glucose catabolism and the pentose phosphate pathway, as possible bottlenecks in the metabolism of the fungus and we had reported the effect of their constitutive production on the growth characteristics of the fungus. In this study, we investigated the effect of their constitutive production on ethanol productivity under anaerobic conditions. We report an increase in ethanol yield and a concomitant decrease in acetic acid production. Metabolomics analysis revealed that the genetic modifications applied did not simply accelerate the metabolic rate of the microorganism; they also affected the relative concentrations of the various metabolites suggesting an increased channeling toward the chorismate pathway, an activation of the γ-aminobutyric acid shunt, and an excess in NADPH regeneration. PMID:27199958

  5. Metabolic Engineering of Fusarium oxysporum to Improve Its Ethanol-Producing Capability.

    PubMed

    Anasontzis, George E; Kourtoglou, Elisavet; Villas-Boâs, Silas G; Hatzinikolaou, Dimitris G; Christakopoulos, Paul

    2016-01-01

    Fusarium oxysporum is one of the few filamentous fungi capable of fermenting ethanol directly from plant cell wall biomass. It has the enzymatic toolbox necessary to break down biomass to its monosaccharides and, under anaerobic and microaerobic conditions, ferments them to ethanol. Although these traits could enable its use in consolidated processes and thus bypass some of the bottlenecks encountered in ethanol production from lignocellulosic material when Saccharomyces cerevisiae is used-namely its inability to degrade lignocellulose and to consume pentoses-two major disadvantages of F. oxysporum compared to the yeast-its low growth rate and low ethanol productivity-hinder the further development of this process. We had previously identified phosphoglucomutase and transaldolase, two major enzymes of glucose catabolism and the pentose phosphate pathway, as possible bottlenecks in the metabolism of the fungus and we had reported the effect of their constitutive production on the growth characteristics of the fungus. In this study, we investigated the effect of their constitutive production on ethanol productivity under anaerobic conditions. We report an increase in ethanol yield and a concomitant decrease in acetic acid production. Metabolomics analysis revealed that the genetic modifications applied did not simply accelerate the metabolic rate of the microorganism; they also affected the relative concentrations of the various metabolites suggesting an increased channeling toward the chorismate pathway, an activation of the γ-aminobutyric acid shunt, and an excess in NADPH regeneration.

  6. Investigations on Fusarium spp. and their mycotoxins causing Fusarium ear rot of maize in Kosovo.

    PubMed

    Shala-Mayrhofer, Vitore; Varga, Elisabeth; Marjakaj, Robert; Berthiller, Franz; Musolli, Agim; Berisha, Defrime; Kelmendi, Bakir; Lemmens, Marc

    2013-01-01

    After wheat, maize (Zea mays L.) is the second most important cereal crop in Kosovo and a major component of animal feed. The purpose of this study was to analyse the incidence and identity of the Fusarium species isolated from naturally infected maize kernels in Kosovo in 2009 and 2010, as well as the mycotoxin contamination. The disease incidence of Fusarium ear rot (from 0.7% to 40% diseased ears) on maize in Kosovo is high. The most frequently Fusarium spp. identified on maize kernels were Fusarium subglutinans, F. verticillioides/F. proliferatum and F. graminearum. Maize kernel samples were analysed by LC-MS/MS and found to be contaminated with deoxynivalenol (DON), DON-3-glucoside, 3-acetyl-DON, 15-acetyl-DON, zearalenone, zearalenone-14-sulphate, moniliformin, fumonisin B1 and fumonisin B2. This is the first report on the incidence and identification of Fusarium species isolated from naturally infected maize as well as the mycotoxin contamination in Kosovo.

  7. Endophytic Fusarium spp. from Roots of Lawn Grass (Axonopus compressus)

    PubMed Central

    Zakaria, Latiffah; Ning, Chua Harn

    2013-01-01

    Fungal endophytes are found inside host plants but do not produce any noticeable disease symptoms in their host. In the present study, endophytic Fusarium species were isolated from roots of lawn grass (Axonopus compressus). A total of 51 isolates were recovered from 100 root segments. Two Fusarium species, F. oxysporum (53%) and F. solani (47%), were identified based on macroconidia and conidiogenous cell morphology. The detection of endophytic F. oxysporum and F. solani in the roots of lawn grass contributes to the knowledge of both the distribution of the two Fusarium species and the importance of roots as endophytic niches for Fusarium species. PMID:24575251

  8. Antifungal activity of Bacillus coagulans against Fusarium sp.

    PubMed

    Czaczyk, Katarzyna; Trojanowska, Krystyna; Mueller, Anna

    2002-01-01

    The antifungal activity of Bacillus coagulans against three pathogenic species of Fusarium was examined. Fungal growth was determined by colony forming units, dry matter and ergosterol level. Biosynthesis of Fusarium mycotoxins was also investigated. The strongest inhibition of fungal growth was noticed when Bacillus coagulans was co-inoculated at the beginning of culture. Estimation of ergosterol level as a determinant of fungal growth showed the greatest degree of Fusarium sp. inhibition. Addition of Bacillus coagulans to Fusarium culmorum culture inhibits the DON (deoxynivalenol) production.

  9. Eugenol oil nanoemulsion: antifungal activity against Fusarium oxysporum f. sp. vasinfectum and phytotoxicity on cottonseeds

    NASA Astrophysics Data System (ADS)

    Abd-Elsalam, Kamel A.; Khokhlov, Alexei R.

    2015-02-01

    The current research deals with the formulation and characterization of bio-based oil-in-water nanoemulsion. The formulated eugenol oil nanoemulsion was characterized by dynamic light scattering, stability test, transmission electron microscopy and thin layer chromatography. The nanoemulsion droplets were found to have a Z-average diameter of 80 nm and TEM study reveals the spherical shape of eugenol oil nanoemulsion (EON). The size of the nanoemulsion was found to be physically stable up to more than 1-month when it was kept at room temperature (25 °C). The TEM micrograph showed that the EON was spherical in shape and moderately mono or di-dispersed and was in the range of 50-110 nm. Three concentrations of the nanoformulation were used to evalute the anti-fusarium activity both in vitro and in vivo experiments. SDS-PAGE results of total protein from the Fusarium oxysporum f. sp. vasinfectum (FOV) isolate before and after treatment with eugenol oil nanoemulsion indicate that the content of extra cellular soluble small molecular proteins decreased significantly in EON-treated fungus. Light micrographs of mycelia and spores treated with EON showed the disruption of the fungal structures. The analysis of variance (ANOVA) for Fusarium wilt incidence indicated highly significant ( p = 0.000) effects of concentration, genotype, and their interaction. The difference in wilt incidence between concentrations and control was not the same for each genotype, that is, the genotypes responded differently to concentrations. Effects of three EON concentration on germination percentage, and radicle length, were determined in the laboratory. One very interesting finding in the current study is that cotton genotypes was the most important factors in determining wilt incidence as it accounted for 93.18 % of the explained (model) variation. In vitro experiments were conducted to evaluate the potential phytotoxic effect of three EON concentrations. Concentration, genotype and

  10. A framework to gauge the epidemic potential of plant pathogens in environmental reservoirs: the example of kiwifruit canker.

    PubMed

    Bartoli, Claudia; Lamichhane, Jay Ram; Berge, Odile; Guilbaud, Caroline; Varvaro, Leonardo; Balestra, Giorgio M; Vinatzer, Boris A; Morris, Cindy E

    2015-02-01

    New economically important diseases on crops and forest trees emerge recurrently. An understanding of where new pathogenic lines come from and how they evolve is fundamental for the deployment of accurate surveillance methods. We used kiwifruit bacterial canker as a model to assess the importance of potential reservoirs of new pathogenic lineages. The current kiwifruit canker epidemic is at least the fourth outbreak of the disease on kiwifruit caused by Pseudomonas syringae in the mere 50 years in which this crop has been cultivated worldwide, with each outbreak being caused by different genetic lines of the bacterium. Here, we ask whether strains in natural (non-agricultural) environments could cause future epidemics of canker on kiwifruit. To answer this question, we evaluated the pathogenicity, endophytic colonization capacity and competitiveness on kiwifruit of P. syringae strains genetically similar to epidemic strains and originally isolated from aquatic and subalpine habitats. All environmental strains possessing an operon involved in the degradation of aromatic compounds via the catechol pathway grew endophytically and caused symptoms in kiwifruit vascular tissue. Environmental and epidemic strains showed a wide host range, revealing their potential as future pathogens of a variety of hosts. Environmental strains co-existed endophytically with CFBP 7286, an epidemic strain, and shared about 20 virulence genes, but were missing six virulence genes found in all epidemic strains. By identifying the specific gene content in genetic backgrounds similar to known epidemic strains, we developed criteria to assess the epidemic potential and to survey for such strains as a means of forecasting and managing disease emergence.

  11. DNA Polymorphisms and Biocontrol of Bacillus Antagonistic to Citrus Bacterial Canker with Indication of the Interference of Phyllosphere Biofilms

    PubMed Central

    Huang, Tzu-Pi; Tzeng, Dean Der-Syh; Wong, Amy C. L.; Chen, Chun-Han; Lu, Kuan-Min; Lee, Ya-Huei; Huang, Wen-Di; Hwang, Bing-Fang; Tzeng, Kuo-Ching

    2012-01-01

    Citrus bacterial canker caused by Xanthomonas axonopodis pv. citri is a devastating disease resulting in significant crop losses in various citrus cultivars worldwide. A biocontrol agent has not been recommended for this disease. To explore the potential of bacilli native to Taiwan to control this disease, Bacillus species with a broad spectrum of antagonistic activity against various phytopathogens were isolated from plant potting mixes, organic compost and the rhizosphere soil. Seven strains TKS1-1, OF3-16, SP4-17, HSP1, WG6-14, TLB7-7, and WP8-12 showing superior antagonistic activity were chosen for biopesticide development. The genetic identity based on 16S rDNA sequences indicated that all seven native strains were close relatives of the B. subtilis group and appeared to be discrete from the B. cereus group. DNA polymorphisms in strains WG6-14, SP4-17, TKS1-1, and WP8-12, as revealed by repetitive sequence-based PCR with the BOXA1R primers were similar to each other, but different from those of the respective Bacillus type strains. However, molecular typing of the strains using either tDNA-intergenic spacer regions or 16S–23S intergenic transcribed spacer regions was unable to differentiate the strains at the species level. Strains TKS1-1 and WG6-14 attenuated symptom development of citrus bacterial canker, which was found to be correlated with a reduction in colonization and biofilm formation by X. axonopodis pv. citri on leaf surfaces. The application of a Bacillus strain TKS1-1 endospore formulation to the leaf surfaces of citrus reduced the incidence of citrus bacterial canker and could prevent development of the disease. PMID:22848728

  12. Outbreak and Spread of Bacterial Canker of Kiwifruit Caused by Pseudomonas syringae pv. actinidiae Biovar 3 in Korea

    PubMed Central

    Kim, Gyoung Hee; Kim, Kwang-Hyung; Son, Kyeong In; Choi, Eu Ddeum; Lee, Young Sun; Jung, Jae Sung; Koh, Young Jin

    2016-01-01

    A bacterial pathogen, Pseudomonas syringae pv. actinidiae (Psa), is a causal agent of kiwifruit bacterial canker worldwide. Psa biovar 3 (Psa3) was first detected in 2011 at an orchard in Dodeok-myeon, Goheunggun, Jeonnam Province in Korea. In this study, we present the results of an epidemiological study regarding Psa3 occurrence on kiwifruit orchards in Korea for the period of 2013 to 2015. Since the first detection of Psa3 in 2011, there was no further case reported by 2013. However, Psa3 was rapidly spreading to 33 orchards in 2014; except for three orchards in Sacheonsi, Gyeongnam Province, most cases were reported in Jeju Island. Entering 2015, bacterial canker by Psa3 became a pandemic in Korea, spreading to 72 orchards in Jeju Island, Jeonnam, and Gyeongnam Provinces. Our epidemiological study indicated that the first Psa3 incidence in 2011 might result from an introduction of Psa3 through imported seedlings from China in 2006. Apart from this, it was estimated that most Psa3 outbreaks from 2014 to 2015 were caused by pollens imported from New Zealand and China for artificial pollination. Most kiwifruit cultivars growing in Korea were infected with Psa3; yellow-fleshed cultivars (Yellow-king, Hort16A, Enza-gold, Zecy-gold, and Haegeum), red-fleshed cultivars (Hongyang and Enza-Red), green-fleshed cultivars (Hayward and Daeheung), and even a kiwiberry (Skinny-green). However, susceptibility to canker differed among cultivars; yellow- and red-fleshed cultivars showed much more severe symptoms compared to the green-fleshed cultivars of kiwifruit and a kiwiberry. PMID:27904461

  13. Engineering canker-resistant plants through CRISPR/Cas9-targeted editing of the susceptibility gene CsLOB1 promoter in citrus.

    PubMed

    Peng, Aihong; Chen, Shanchun; Lei, Tiangang; Xu, Lanzhen; He, Yongrui; Wu, Liu; Yao, Lixiao; Zou, Xiuping

    2017-03-29

    Citrus canker, caused by Xanthomonas citri subsp. citri (Xcc), is severely damaging to the global citrus industry. Targeted editing of host disease-susceptibility genes represents an interesting and potentially durable alternative in plant breeding for resistance. Here, we report improvement of citrus canker resistance through CRISPR/Cas9-targeted modification of the susceptibility gene CsLOB1 promoter in citrus. Wanjincheng orange (Citrus sinensis Osbeck) harbors at least three copies of the CsLOB1(G) allele and one copy of the CsLOB1(-) allele. The promoter of both alleles contains the effector binding element (EBEPthA4 ), which is recognized by the main effector PthA4 of Xcc to activate CsLOB1 expression to promote citrus canker development. Five pCas9/CsLOB1sgRNA constructs were designed to modify the EBEPthA4 of the CsLOB1 promoter in Wanjincheng orange. Among these constructs, mutation rates were 11.5% to 64.7%. Homozygous mutants were generated directly from citrus explants. Sixteen lines that harbored EBEPthA4 modifications were identified from 38 mutant plants. Four mutation lines (S2-5, S2-6, S2-12 and S5-13), in which promoter editing disrupted CsLOB1 induction in response to Xcc infection, showed enhanced resistance to citrus canker compared with the wild type. No canker symptoms were observed in the S2-6 and S5-13 lines. Promoter editing of CsLOB1(G) alone was sufficient to enhance citrus canker resistance in Wanjincheng orange. Deletion of the entire EBEPthA4 sequence from both CsLOB1 alleles conferred a high degree of resistance to citrus canker. The results demonstrate that CRISPR/Cas9-mediated promoter editing of CsLOB1 is an efficient strategy for generation of canker-resistant citrus cultivars. This article is protected by copyright. All rights reserved.

  14. Deoxynivalenol and other selected Fusarium toxins in Swedish oats--occurrence and correlation to specific Fusarium species.

    PubMed

    Fredlund, Elisabeth; Gidlund, Ann; Sulyok, Michael; Börjesson, Thomas; Krska, Rudolf; Olsen, Monica; Lindblad, Mats

    2013-10-15

    Fusarium moulds frequently contaminate oats and other cereals world-wide, including those grown in Northern Europe. To investigate the presence of toxigenic Fusarium species and their toxins in oats, samples were taken during 2010 and 2011 in three geographical regions of Sweden (east, west, south). The samples were analysed by real-time PCR for the specific infection level of seven Fusarium species associated with oats and other cereals (Fusarium poae, Fusarium graminearum, Fusarium langsethiae, Fusarium culmorum, Fusarium tricinctum, Fusarium sporotrichioides and Fusarium avenaceum) and with a multi-mycotoxin method based on liquid chromatography/electrospray ionisation-tandem mass spectrometry (HPLC/ESI-MS/MS) for the detection of many fungal metabolites, including deoxynivalenol (DON), zearalenone (ZEA), nivalenol (NIV), T-2 toxin, HT-2 toxins, moniliformin (MON), beauvericin (BEA) and enniatins (ENNs). Most samples contained at least four of the seven Fusarium species analysed and F. poae, F. langsethiae and F. avenaceum were present in approximately 90-100% of all samples. The most common toxins detected were DON, NIV, BEA and ENNs, which were present in more than 90% of samples. Most Fusarium species and their toxins occurred in higher concentrations in 2010 than in 2011, with the exception of DON and its main producer F. graminearum. Significant regional differences were detected for some moulds and mycotoxins, with higher levels of F. graminearum, DON and ZEA in western Sweden than in the east (P<0.05) and higher levels of F. tricinctum and MON in the south (P<0.05). Correlation analysis showed significant correlations between many Fusarium species and toxin levels. For example, F. tricinctum was significantly correlated to F. avenaceum (r = 0.72, P<0.001), DON to ZEA (r = 0.52, P<0.001), DON to F. graminearum (r = 0.77, P<0.001) and the sum of T-2 and HT-2 to F. langsethiae (r = 0.77, P<0.001). The multi-toxin approach employed allowed simultaneous

  15. Identification of putative TAL effector targets of the citrus canker pathogens shows functional convergence underlying disease development and defense response

    PubMed Central

    2014-01-01

    Background Transcriptional activator-like (TAL) effectors, formerly known as the AvrBs3/PthA protein family, are DNA-binding effectors broadly found in Xanthomonas spp. that transactivate host genes upon injection via the bacterial type three-secretion system. Biologically relevant targets of TAL effectors, i.e. host genes whose induction is vital to establish a compatible interaction, have been reported for xanthomonads that colonize rice and pepper; however, citrus genes modulated by the TAL effectors PthA“s” and PthC“s” of the citrus canker bacteria Xanthomonas citri (Xc) and Xanthomonas aurantifolii pathotype C (XaC), respectively, are poorly characterized. Of particular interest, XaC causes canker disease in its host lemon (Citrus aurantifolia), but triggers a defense response in sweet orange. Results Based on, 1) the TAL effector-DNA binding code, 2) gene expression data of Xc and XaC-infiltrated sweet orange leaves, and 3) citrus hypocotyls transformed with PthA2, PthA4 or PthC1, we have identified a collection of Citrus sinensis genes potentially targeted by Xc and XaC TAL effectors. Our results suggest that similar with other strains of Xanthomonas TAL effectors, PthA2 and PthA4, and PthC1 to some extent, functionally converge. In particular, towards induction of genes involved in the auxin and gibberellin synthesis and response, cell division, and defense response. We also present evidence indicating that the TAL effectors act as transcriptional repressors and that the best scoring predicted DNA targets of PthA“s” and PthC“s” in citrus promoters predominantly overlap with or localize near to TATA boxes of core promoters, supporting the idea that TAL effectors interact with the host basal transcriptional machinery to recruit the RNA pol II and start transcription. Conclusions The identification of PthA“s” and PthC“s” targets, such as the LOB (LATERAL ORGAN BOUNDARY) and CCNBS genes that we report here, is key for the understanding

  16. Rapid and sensitive detection of Citrus Bacterial Canker by loop-mediated isothermal amplification combined with simple visual evaluation methods

    PubMed Central

    2010-01-01

    Background Citrus Bacterial Canker (CBC) is a major, highly contagious disease of citrus plants present in many countries in Asia, Africa and America, but not in the Mediterranean area. There are three types of Citrus Bacterial Canker, named A, B, and C that have different genotypes and posses variation in host range within citrus species. The causative agent for type A CBC is Xanthomonas citri subsp. citri, while Xanthomonas fuscans subsp. aurantifolii, strain B causes type B CBC and Xanthomonas fuscans subsp. aurantifolii strain C causes CBC type C. The early and accurate identification of those bacteria is essential for the protection of the citrus industry. Detection methods based on bacterial isolation, antibodies or polymerase chain reaction (PCR) have been developed previously; however, these approaches may be time consuming, laborious and, in the case of PCR, it requires expensive laboratory equipment. Loop-mediated isothermal amplification (LAMP), which is a novel isothermal DNA amplification technique, is sensitive, specific, fast and requires no specialized laboratory equipment. Results A loop-mediated isothermal amplification assay for the diagnosis of Citrus Bacterial Canker (CBC-LAMP) was developed and evaluated. DNA samples were obtained from infected plants or cultured bacteria. A typical ladder-like pattern on gel electrophoresis was observed in all positive samples in contrast to the negative controls. In addition, amplification products were detected by visual inspection using SYBRGreen and using a lateral flow dipstick, eliminating the need for gel electrophoresis. The sensitivity and specificity of the assay were evaluated in different conditions and using several sample sources which included purified DNA, bacterium culture and infected plant tissue. The sensitivity of the CBC-LAMP was 10 fg of pure Xcc DNA, 5 CFU in culture samples and 18 CFU in samples of infected plant tissue. No cross reaction was observed with DNA of other phytopathogenic

  17. Chemotactic signal transduction and phosphate metabolism as adaptive strategies during citrus canker induction by Xanthomonas citri.

    PubMed

    Moreira, Leandro Marcio; Facincani, Agda Paula; Ferreira, Cristiano Barbalho; Ferreira, Rafael Marine; Ferro, Maria Inês Tiraboshi; Gozzo, Fabio Cesar; de Oliveira, Julio Cezar Franco; Ferro, Jesus Aparecido; Soares, Márcia Regina

    2015-03-01

    The genome of Xanthomonas citri subsp. Citri strain 306 pathotype A (Xac) was completely sequenced more than 10 years; to date, few studies involving functional genomics Xac and its host compatible have been developed, specially related to adaptive events that allow the survival of Xac within the plant. Proteomic analysis of Xac showed that the processes of chemotactic signal transduction and phosphate metabolism are key adaptive strategies during the interaction of a pathogenic bacterium with its plant host. The results also indicate the importance of a group of proteins that may not be directly related to the classical virulence factors, but that are likely fundamental to the success of the initial stages of the infection, such as methyl-accepting chemotaxis protein (Mcp) and phosphate specific transport (Pst). Furthermore, the analysis of the mutant of the gene pstB which codifies to an ABC phosphate transporter subunit revealed a complete absence of citrus canker symptoms when inoculated in compatible hosts. We also conducted an in silico analysis which established the possible network of genes regulated by two-component systems PhoPQ and PhoBR (related to phosphate metabolism), and possible transcriptional factor binding site (TFBS) motifs of regulatory proteins PhoB and PhoP, detaching high degree of conservation of PhoB TFBS in 84 genes of Xac genome. This is the first time that chemotaxis signal transduction and phosphate metabolism were therefore indicated to be fundamental to the process of colonization of plant tissue during the induction of disease associated with Xanthomonas genus bacteria.

  18. Lateral organ boundaries 1 is a disease susceptibility gene for citrus bacterial canker disease.

    PubMed

    Hu, Yang; Zhang, Junli; Jia, Hongge; Sosso, Davide; Li, Ting; Frommer, Wolf B; Yang, Bing; White, Frank F; Wang, Nian; Jones, Jeffrey B

    2014-01-28

    Citrus bacterial canker (CBC) disease occurs worldwide and incurs considerable costs both from control measures and yield losses. Bacteria that cause CBC require one of six known type III transcription activator-like (TAL) effector genes for the characteristic pustule formation at the site of infection. Here, we show that Xanthomonas citri subspecies citri strain Xcc306, with the type III TAL effector gene pthA4 or with the distinct yet biologically equivalent gene pthAw from strain XccA(w), induces two host genes, CsLOB1 and CsSWEET1, in a TAL effector-dependent manner. CsLOB1 is a member of the Lateral Organ Boundaries (LOB) gene family of transcription factors, and CsSWEET1 is a homolog of the SWEET sugar transporter and rice disease susceptibility gene. Both TAL effectors drive expression of CsLOB1 and CsSWEET1 promoter reporter gene fusions when coexpressed in citrus or Nicotiana benthamiana. Artificially designed TAL effectors directed to sequences in the CsLOB1 promoter region, but not the CsSWEET1 promoter, promoted pustule formation and higher bacterial leaf populations. Three additional distinct TAL effector genes, pthA*, pthB, and pthC, also direct pustule formation and expression of CsLOB1. Unlike pthA4 and pthAw, pthB and pthC do not promote the expression of CsSWEET1. CsLOB1 expression was associated with the expression of genes associated with cell expansion. The results indicate that CBC-inciting species of Xanthomonas exploit a single host disease susceptibility gene by altering the expression of an otherwise developmentally regulated gene using any one of a diverse set of TAL effector genes in the pathogen populations.

  19. Lateral organ boundaries 1 is a disease susceptibility gene for citrus bacterial canker disease

    PubMed Central

    Hu, Yang; Zhang, Junli; Jia, Hongge; Sosso, Davide; Li, Ting; Frommer, Wolf B.; Yang, Bing; White, Frank F.; Wang, Nian; Jones, Jeffrey B.

    2014-01-01

    Citrus bacterial canker (CBC) disease occurs worldwide and incurs considerable costs both from control measures and yield losses. Bacteria that cause CBC require one of six known type III transcription activator-like (TAL) effector genes for the characteristic pustule formation at the site of infection. Here, we show that Xanthomonas citri subspecies citri strain Xcc306, with the type III TAL effector gene pthA4 or with the distinct yet biologically equivalent gene pthAw from strain XccAw, induces two host genes, CsLOB1 and CsSWEET1, in a TAL effector-dependent manner. CsLOB1 is a member of the Lateral Organ Boundaries (LOB) gene family of transcription factors, and CsSWEET1 is a homolog of the SWEET sugar transporter and rice disease susceptibility gene. Both TAL effectors drive expression of CsLOB1 and CsSWEET1 promoter reporter gene fusions when coexpressed in citrus or Nicotiana benthamiana. Artificially designed TAL effectors directed to sequences in the CsLOB1 promoter region, but not the CsSWEET1 promoter, promoted pustule formation and higher bacterial leaf populations. Three additional distinct TAL effector genes, pthA*, pthB, and pthC, also direct pustule formation and expression of CsLOB1. Unlike pthA4 and pthAw, pthB and pthC do not promote the expression of CsSWEET1. CsLOB1 expression was associated with the expression of genes associated with cell expansion. The results indicate that CBC-inciting species of Xanthomonas exploit a single host disease susceptibility gene by altering the expression of an otherwise developmentally regulated gene using any one of a diverse set of TAL effector genes in the pathogen populations. PMID:24474801

  20. Bayesian analysis for inference of an emerging epidemic: citrus canker in urban landscapes.

    PubMed

    Neri, Franco M; Cook, Alex R; Gibson, Gavin J; Gottwald, Tim R; Gilligan, Christopher A

    2014-04-01

    Outbreaks of infectious diseases require a rapid response from policy makers. The choice of an adequate level of response relies upon available knowledge of the spatial and temporal parameters governing pathogen spread, affecting, amongst others, the predicted severity of the epidemic. Yet, when a new pathogen is introduced into an alien environment, such information is often lacking or of no use, and epidemiological parameters must be estimated from the first observations of the epidemic. This poses a challenge to epidemiologists: how quickly can the parameters of an emerging disease be estimated? How soon can the future progress of the epidemic be reliably predicted? We investigate these issues using a unique, spatially and temporally resolved dataset for the invasion of a plant disease, Asiatic citrus canker in urban Miami. We use epidemiological models, Bayesian Markov-chain Monte Carlo, and advanced spatial statistical methods to analyse rates and extent of spread of the disease. A rich and complex epidemic behaviour is revealed. The spatial scale of spread is approximately constant over time and can be estimated rapidly with great precision (although the evidence for long-range transmission is inconclusive). In contrast, the rate of infection is characterised by strong monthly fluctuations that we associate with extreme weather events. Uninformed predictions from the early stages of the epidemic, assuming complete ignorance of the future environmental drivers, fail because of the unpredictable variability of the infection rate. Conversely, predictions improve dramatically if we assume prior knowledge of either the main environmental trend, or the main environmental events. A contrast emerges between the high detail attained by modelling in the spatiotemporal description of the epidemic and the bottleneck imposed on epidemic prediction by the limits of meteorological predictability. We argue that identifying such bottlenecks will be a fundamental step in

  1. Bayesian Analysis for Inference of an Emerging Epidemic: Citrus Canker in Urban Landscapes

    PubMed Central

    Neri, Franco M.; Cook, Alex R.; Gibson, Gavin J.; Gottwald, Tim R.; Gilligan, Christopher A.

    2014-01-01

    Outbreaks of infectious diseases require a rapid response from policy makers. The choice of an adequate level of response relies upon available knowledge of the spatial and temporal parameters governing pathogen spread, affecting, amongst others, the predicted severity of the epidemic. Yet, when a new pathogen is introduced into an alien environment, such information is often lacking or of no use, and epidemiological parameters must be estimated from the first observations of the epidemic. This poses a challenge to epidemiologists: how quickly can the parameters of an emerging disease be estimated? How soon can the future progress of the epidemic be reliably predicted? We investigate these issues using a unique, spatially and temporally resolved dataset for the invasion of a plant disease, Asiatic citrus canker in urban Miami. We use epidemiological models, Bayesian Markov-chain Monte Carlo, and advanced spatial statistical methods to analyse rates and extent of spread of the disease. A rich and complex epidemic behaviour is revealed. The spatial scale of spread is approximately constant over time and can be estimated rapidly with great precision (although the evidence for long-range transmission is inconclusive). In contrast, the rate of infection is characterised by strong monthly fluctuations that we associate with extreme weather events. Uninformed predictions from the early stages of the epidemic, assuming complete ignorance of the future environmental drivers, fail because of the unpredictable variability of the infection rate. Conversely, predictions improve dramatically if we assume prior knowledge of either the main environmental trend, or the main environmental events. A contrast emerges between the high detail attained by modelling in the spatiotemporal description of the epidemic and the bottleneck imposed on epidemic prediction by the limits of meteorological predictability. We argue that identifying such bottlenecks will be a fundamental step in

  2. Etiology and Epidemiological Conditions Promoting Fusarium Root Rot in Sweetpotato.

    PubMed

    Scruggs, A C; Quesada-Ocampo, L M

    2016-08-01

    Sweetpotato production in the United States is limited by several postharvest diseases, and one of the most common is Fusarium root rot. Although Fusarium solani is believed to be the primary causal agent of disease, numerous other Fusarium spp. have been reported to infect sweetpotato. However, the diversity of Fusarium spp. infecting sweetpotato in North Carolina is unknown. In addition, the lack of labeled and effective fungicides for control of Fusarium root rot in sweetpotato creates the need for integrated strategies to control disease. Nonetheless, epidemiological factors that promote Fusarium root rot in sweetpotato remain unexplored. A survey of Fusarium spp. infecting sweetpotato in North Carolina identified six species contributing to disease, with F. solani as the primary causal agent. The effects of storage temperature (13, 18, 23, 29, and 35°C), relative humidity (80, 90, and 100%), and initial inoculum level (3-, 5-, and 7-mm-diameter mycelia plug) were examined for progression of Fusarium root rot caused by F. solani and F. proliferatum on 'Covington' sweetpotato. Fusarium root rot was significantly reduced (P < 0.05) at lower temperatures (13°C), low relative humidity levels (80%), and low initial inoculum levels for both pathogens. Sporulation of F. proliferatum was also reduced under the same conditions. Qualitative mycotoxin analysis of roots infected with one of five Fusarium spp. revealed the production of fumonisin B1 by F. proliferatum when infecting sweetpotato. This study is a step toward characterizing the etiology and epidemiology of Fusarium root rot in sweetpotato, which allows for improved disease management recommendations to limit postharvest losses to this disease.

  3. Diversity of Fusarium Species from Highland Areas in Malaysia

    PubMed Central

    Manshor, Nurhazrati; Rosli, Hafizi; Ismail, Nor Azliza; Salleh, Baharuddin; Zakaria, Latiffah

    2012-01-01

    Fusarium is a cosmopolitan and highly diversified genus of saprophytic, phytopathogenic and toxigenic fungi. However, the existence and diversity of a few species of Fusarium are restricted to a certain area or climatic condition. The present study was conducted to determine the occurrence and diversity of Fusarium species in tropical highland areas in Malaysia and to compare with those in temperate and subtropical regions. A series of sampling was carried out in 2005 to 2009 at several tropical highland areas in Malaysia that is: Cameron Highlands, Fraser Hills and Genting Highlands in Pahang; Penang Hill in Penang; Gunung Jerai in Kedah; Kundasang and Kinabalu Park in Sabah; Kubah National Park and Begunan Hill in Sarawak. Sampling was done randomly from various hosts and substrates. Isolation of Fusarium isolates was done by using pentachloronitrobenzene (PCNB) agar and 1449 isolates of Fusarium were successfully recovered. Based on morphological characteristics, 20 species of Fusarium were identified. The most prevalent species occurring on the highlands areas was F. solani (66.1%) followed by F. graminearum (8.5%), F. oxysporum (7.8%), F. semitectum (5.7%), F. subglutinans (3.5%) and F. proliferatum (3.4%). Other Fusarium species, namely F. avenaceum, F. camptoceras, F. chlamydosporum, F. compactum, F. crookwellense, F. culmorum, F. decemcellulare, F. equiseti, F. nygamai, F. poae, F. proliferatum, F. sacchari, F. sporotrichioides, F. sterilihyphosum and F. verticillioides accounted for 1% recoveries. The present study was the first report on the occurrences of Fusarium species on highland areas in Malaysia. PMID:24575229

  4. NIRS method for precise identification of Fusarium damaged wheat kernels

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Development of scab resistant wheat varieties may be enhanced by non-destructive evaluation of kernels for Fusarium damaged kernels (FDKs) and deoxynivalenol (DON) levels. Fusarium infection generally affects kernel appearance, but insect damage and other fungi can cause similar symptoms. Also, some...

  5. High speed sorting of Fusarium-damaged wheat kernels

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Recent studies have found that resistance to Fusarium fungal infection can be inherited in wheat from one generation to another. However, there is not yet available a cost effective method to separate Fusarium-damaged wheat kernels from undamaged kernels so that wheat breeders can take advantage of...

  6. Diversity of the Fusarium graminearum species complex on French cereals

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Fusarium graminearum is an important pathogen causing Fusarium head blight (FHB) on wheat and barley and Gibberella ear rot (GER) on maize, and harvested grains often are contaminated with trichothecenes such as deoxynivalenol (DON) and nivalenol (NIV) that are a major health and food safety concern...

  7. Metabolomic studies for the interaction Glycine max- Fusarium tucumaniae

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Sudden-death syndrome (SDS) of soybean can be caused in Argentina by 4 different Fusarium species: F. brasiliense, F. crassistipitatum, F. tucumaniae and F. virguliforme. Fusarium tucumaniae and F. virguliforme are the primary etiological agents of soybean SDS in Argentina and United States, respect...

  8. Exploring Fusarium head blight disease control by RNA interference

    Technology Transfer Automated Retrieval System (TEKTRAN)

    RNA interference (RNAi) technology provides a novel tool to study gene function and plant protection strategies. Fusarium graminearum is the causal agent of Fusarium head blight (FHB), which reduces crop yield and quality by producing trichothecene mycotoxins including 3-acetyl deoxynivalenol (3-ADO...

  9. Genomics and evolution of secondary metabolism in Fusarium

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Fusarium is a species-rich genus that causes disease on virtually all plant crops and produces diverse secondary metabolites (SMs), including pigments, plant hormones, and some of the mycotoxins of greatest concern to food and feed safety. To better understand the potential SM diversity in Fusarium ...

  10. A diagnostic guide for Fusarium Root Rot of pea

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Fusarium root rot, caused by Fusarium solani f. sp. pisi, is a major root rot pathogen in pea production areas worldwide. Here we provide a diagnostic guide that describes: the taxonomy of the pathogen, signs and symptoms of the pathogen, host range, geographic distribution, methods used to isolate ...

  11. Genome, Proteome and Structure of a T7-Like Bacteriophage of the Kiwifruit Canker Phytopathogen Pseudomonas syringae pv. actinidiae.

    PubMed

    Frampton, Rebekah A; Acedo, Elena Lopez; Young, Vivienne L; Chen, Danni; Tong, Brian; Taylor, Corinda; Easingwood, Richard A; Pitman, Andrew R; Kleffmann, Torsten; Bostina, Mihnea; Fineran, Peter C

    2015-06-24

    Pseudomonas syringae pv. actinidiae is an economically significant pathogen responsible for severe bacterial canker of kiwifruit (Actinidia sp.). Bacteriophages infecting this phytopathogen have potential as biocontrol agents as part of an integrated approach to the management of bacterial canker, and for use as molecular tools to study this bacterium. A variety of bacteriophages were previously isolated that infect P. syringae pv. actinidiae, and their basic properties were characterized to provide a framework for formulation of these phages as biocontrol agents. Here, we have examined in more detail φPsa17, a phage with the capacity to infect a broad range of P. syringae pv. actinidiae strains and the only member of the Podoviridae in this collection. Particle morphology was visualized using cryo-electron microscopy, the genome was sequenced, and its structural proteins were analysed using shotgun proteomics. These studies demonstrated that φPsa17 has a 40,525 bp genome, is a member of the T7likevirus genus and is closely related to the pseudomonad phages φPSA2 and gh-1. Eleven structural proteins (one scaffolding) were detected by proteomics and φPsa17 has a capsid of approximately 60 nm in diameter. No genes indicative of a lysogenic lifecycle were identified, suggesting the phage is obligately lytic. These features indicate that φPsa17 may be suitable for formulation as a biocontrol agent of P. syringae pv. actinidiae.

  12. Variables Associated with Severity of Bacterial Canker and Wilt Caused by Clavibacter michiganensis subsp. michiganensis in Tomato Greenhouses.

    PubMed

    Blank, L; Cohen, Y; Borenstein, M; Shulhani, R; Lofthouse, M; Sofer, M; Shtienberg, D

    2016-03-01

    Clavibacter michiganensis subsp. michiganensis, the causal agent of bacterial canker and wilt of tomato, is considered to be one of the most important bacterial pathogens worldwide. In the year 2000 there was an increase in the number of infected greenhouses and in the severity of the disease in Israel. As part of the effort to cope with the disease, a comprehensive survey was conducted. Scouts recorded disease severity monthly in 681 production units. At the end of the season the scouts met with the growers and together recorded relevant details about the crop and cultural practices employed. The results suggested an absence of anisotropy pattern in the study region. Global Moran's I analysis showed that disease severity had significant spatial autocorrelation. The strongest spatial autocorrelation occurred within a 1,500 m neighborhood, which is comparable to the distance between production units maintained by one grower (Farm). Next, we tested three groups of variables including or excluding the Farm as a variable. When the Farm was included the explained variation increased in all the studied models. Overall, results of this study demonstrate that the most influential factor on bacterial canker severity was the Farm. This variable probably encompasses variation in experience, differences in agricultural practices between growers, and the quality of implementation of management practices.

  13. Exogenous treatment with salicylic acid attenuates occurrence of citrus canker in susceptible navel orange (Citrus sinensis Osbeck).

    PubMed

    Wang, Yin; Liu, Ji-Hong

    2012-08-15

    Citrus canker caused by Xanthomonas axonopodis pv. citri (Xac) is a devastating bacterial disease threatening the citrus industry. Salicylic acid (SA) plays a key role in plant defense response to biotic stress, but information is scarce concerning the application of SA to enhancing Xac resistance. In the present research attempts were made to investigate how exogenous application of SA influenced canker disease outbreak in navel orange (Citrus sinensis). Exogenously applied SA at 0.25 mM significantly enhanced the endogenous free and bound SA, particularly the latter. Upon exposure to Xac, lower disease incidence rate and smaller lesion sites were observed in the samples pre-treated with SA, accompanied by repression of bacterial growth at the lesion sites. Concurrent with the augmented disease resistance, SA-treated leaves had higher H₂O₂ level and smaller stomata apertures before or after Xac infection when compared with their counterparts pre-treated with water (control). SA treatment elevated the activities of phenylalanine ammonia-lyase and β-1,3-glucanase, but only the latter was higher in the SA-treated samples after Xac infection. In addition, mRNA levels of two pathogenesis-related genes, CsCHI and CsPR4A, were higher in the SA-treated samples relative to the control. Taken together, our results strongly suggest that the exogenously applied SA has evoked a cascade of physiological and molecular events that function singly or in concert to confer resistance to Xac invasion.

  14. Release of pea germplasm with Fusarium resistance combined with desirable yield and anti-lodging traits

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Fusarium root rot caused by Fusarium solani f. sp. pisi (Fsp) and Fusarium wilt caused by Fusarium oxysporum f. sp. pisi (Fop) races 1, 2 and 5, negatively impact the pea industry worldwide. Limited pea germplasm with agronomically acceptable characteristics combined with resistance to these disease...

  15. Adventitious sporulation in Fusarium: The yeast that were not

    PubMed Central

    Lockwood, Matthew B.; Crescencio, Juan Carlos Rico

    2015-01-01

    In immunocompromised patients, Fusarium species cause infections that lead to high mortality. Our case report describes a case of disseminated fusariosis in a neutropenic patient with AML after myelosuppressive chemotherapy, and a neutropenic multiple myeloma patient with Fusarium fungemia awaiting stem cell collection. Both cases highlight the fact that Fusarium can grow as yeast-like structures in the blood causing a delay in diagnosis, and that Fusarium has a tendency to be a resistant organism. Fusarium was only susceptible to amphotericin B in both cases, but we chose to continue treatment with voriconazole in the first case with disseminated infection, despite culture results, in view of his good clinical response. Despite high mortality rates in disseminated infection, our two patients had good outcomes. PMID:26793480

  16. Soybean SDS in South Africa is caused by Fusarium brasiliense and a novel undescribed Fusarium sp.

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Soybean sudden death syndrome (SDS) was detected in South Africa for the first time during pathogen surveys conducted in 2013-2014. The primary objective of this study was to characterize the 16 slow-growing Fusarium strains that were isolated from the roots of symptomatic plants. Molecular phylogen...

  17. In Vitro Antifungal Susceptibility and Molecular Characterization of Clinical Isolates of Fusarium verticillioides (F. moniliforme) and Fusarium thapsinum▿

    PubMed Central

    Azor, Mónica; Gené, Josepa; Cano, Josep; Sutton, Deanna A.; Fothergill, Annette W.; Rinaldi, Michael G.; Guarro, Josep

    2008-01-01

    A microdilution method was used to test 11 antifungal drugs against clinical isolates of Fusarium thapsinum and three different phylogenetic clades of Fusarium verticillioides that were characterized by sequencing a region of the β-tubulin gene. Terbinafine was the most-active drug against both species, followed by posaconazole against F. verticillioides. PMID:18391027

  18. Wind speed effects on the quantity of Xanthomonas citri subsp. citri dispersed downwind from canopies of grapefruit trees infected with citrus canker

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The epidemic of citrus canker (Xanthomonas citri subsp. citri, Xcc) in Florida continues to expand since termination of the eradication program in 2006. Storms are known to be associated with disease spread, but little information exists on the interaction of fundamental physical and biological proc...

  19. Characterization of Cytospora isolates from wood cankers of declining grapevine in North America, with the descriptions of two new Cytospora species

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Cytospora species are ubiquitous pathogens of woody plants, causing dieback and wood cankers in numerous perennial hosts, including agronomic crops (e.g., Prunus), timber trees (e.g., Eucalyptus), and riparian hosts (e.g., Salix). Cytospora chrysosperma, C. cincta, and C. leucostoma have been report...

  20. Processess involved in the dispersal of Xanthomonas citri pv. citri from canker-infected citrus canopies, and in the infection of citrus foliage

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Citrus canker (Xanthomonas citri subsp. citri, Xcc) is now considered endemic in Florida, and epidemics result in yield loss and market penalties both in Florida and elsewhere, where the pathogen occurs and susceptible citrus is cultivated. The bacterium is dispersed in rain splash, and storms with...

  1. Processes involved in the dispersal of Xanthomonas citri pv. citri from canker-infectd citrus canopies, and in the infection of citrus foliage

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Citrus canker (Xanthomonas citri subsp. citri, Xcc) is now considered endemic in Florida, and epidemics result in yield loss and market penalties both in Florida, and elsewhere where the pathogen occurs, and susceptible citrus is cultivated. The bacterium is dispersed in rain splash, and storms wit...

  2. Complete Genome Sequences of Six Copper-Resistant Xanthomonas citri pv. citri Strains Causing Asiatic Citrus Canker, Obtained Using Long-Read Technology

    PubMed Central

    Richard, Damien; Boyer, Claudine; Vernière, Christian; Canteros, Blanca I.; Lefeuvre, Pierre

    2017-01-01

    ABSTRACT The gammaproteobacterium Xanthomonas citri pv. citri causes Asiatic citrus canker. Pathotype A strains have a broad host range, which includes most commercial citrus species, and they cause important economic losses worldwide. Control often relies on frequent copper sprays. We present here the complete genomes of six X. citri pv. citri copper-resistant strains. PMID:28336584

  3. Development of consumer-friendly transgenic citrus plants with potential broad spectrum resistance to HLB, Citrus canker, Phytopthora and other exotic diseases

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The second year of this CRB funded project has started, which is focused on the development of citrus cultivars that exhibit disease resistance to multiple pathogens such as HLB, Phytophthora and citrus canker diseases. We are using precise genetic engineering to introduce into disease susceptible ...

  4. The epidemiological significance of post-packinghouse survival of Xanthomonas citri ssp. citri for dissemination of Asiatic citrus canker via infected fruit

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The risk of introduction of Xanthomonas citri spp. citri (Xcc) to new, unaffected citrus producing areas is a major concern for those citrus industries attempting to remain free of citrus canker. Citrus fruit, as a potential pathway for Xcc to enter and become established in these areas, is assumed...

  5. Inducible expression of Bs2 R gene from Capsicum chacoense in sweet orange (Citrus sinensis L. Osbeck) confers enhanced resistance to citrus canker disease.

    PubMed

    Sendín, Lorena Noelia; Orce, Ingrid Georgina; Gómez, Rocío Liliana; Enrique, Ramón; Grellet Bournonville, Carlos Froilán; Noguera, Aldo Sergio; Vojnov, Adrián Alberto; Marano, María Rosa; Castagnaro, Atilio Pedro; Filippone, María Paula

    2017-04-01

    Transgenic expression of the pepper Bs2 gene confers resistance to Xanthomonas campestris pv. vesicatoria (Xcv) pathogenic strains which contain the avrBs2 avirulence gene in susceptible pepper and tomato varieties. The avrBs2 gene is highly conserved among members of the Xanthomonas genus, and the avrBs2 of Xcv shares 96% homology with the avrBs2 of Xanthomonas citri subsp. citri (Xcc), the causal agent of citrus canker disease. A previous study showed that the transient expression of pepper Bs2 in lemon leaves reduced canker formation and induced plant defence mechanisms. In this work, the effect of the stable expression of Bs2 gene on citrus canker resistance was evaluated in transgenic plants of Citrus sinensis cv. Pineapple. Interestingly, Agrobacterium-mediated transformation of epicotyls was unsuccessful when a constitutive promoter (2× CaMV 35S) was used in the plasmid construction, but seven transgenic lines were obtained with a genetic construction harbouring Bs2 under the control of a pathogen-inducible promoter, from glutathione S-transferase gene from potato. A reduction of disease symptoms of up to 70% was observed in transgenic lines expressing Bs2 with respect to non-transformed control plants. This reduction was directly dependent on the Xcc avrBs2 gene since no effect was observed when a mutant strain of Xcc with a disruption in avrBs2 gene was used for inoculations. Additionally, a canker symptom reduction was correlated with levels of the Bs2 expression in transgenic plants, as assessed by real-time qPCR, and accompanied by the production of reactive oxygen species. These results indicate that the pepper Bs2 resistance gene is also functional in a family other than the Solanaceae, and could be considered for canker control.

  6. Responsiveness of different citrus genotypes to the Xanthomonas citri ssp. citri-derived pathogen-associated molecular pattern (PAMP) flg22 correlates with resistance to citrus canker.

    PubMed

    Shi, Qingchun; Febres, Vicente J; Jones, Jeffrey B; Moore, Gloria A

    2015-06-01

    The bacterial agent of citrus canker disease (Xanthomonas citri ssp. citri, Xcc) has caused tremendous economic losses to the citrus industry around the world. Pathogen-associated molecular pattern (PAMP)-triggered immunity (PTI) is important to plant immunity. In this study, we compared the defence responses of citrus canker-resistant and citrus canker-susceptible genotypes to the Xcc-derived PAMP flg22 (Xflg22) by analysing the expression of 20 citrus defence-associated genes. We showed that, in the most resistant genotype, 'Nagami' kumquat, there was significant induction of several defence genes (EDS1, NDR1, PBS1, RAR1, SGT1, PAL1, NPR2 and NPR3) as early as 6 h and up to 72 h after Xflg22 treatment. At the other end of the spectrum, highly susceptible 'Duncan' grapefruit showed no induction of the same defence genes, even 120 h after treatment. Citrus genotypes with partial levels of resistance showed intermediate levels of transcriptional reprogramming that correlated with their resistance level. Xflg22 also triggered a rapid oxidative burst in all genotypes which was higher and accompanied by the induction of PTI marker genes (WRKY22 and GST1) only in the more resistant genotypes. Pretreatment with Xflg22 prior to Xcc inoculation inhibited bacterial growth in kumquat, but not in grapefruit. A flagellin-deficient Xcc strain (XccΔfliC) showed greater growth increase relative to wild-type Xcc in kumquat than in grapefruit. Taken together, our results indicate that Xflg22 initiates strong PTI in canker-resistant genotypes, but not in susceptible ones, and that a robust induction of PTI is an important component of citrus resistance to canker.

  7. Use of a climatic rule and fuzzy sets to model geographic distribution of climatic risk for European canker (Neonectria galligena) of apple.

    PubMed

    Kim, Kwang Soo; Beresford, Robert M

    2012-02-01

    A rule-based model was developed to assess climatic risk of European canker (Neonectria galligena), which is a major disease of apple in some temperate zones. A descriptive rule was derived from published observations on climatic conditions favorable for European canker development. Fuzzy set theory was used to evaluate the descriptive rule quantitatively. The amount and frequency of rainfall and the average number of hours between 11 and 16°C/day were used as input variables whose values were matched with terms in the rule, e.g., 'high' or 'low'. The degree of a term, e.g., the state of being high or low, to a given input value was determined using a membership function that converts an input value to a number between 0 and 1. The rule was evaluated by combining the degree of the terms associated with monthly climate data. Monthly risk index values derived using the rule were combined for pairs of consecutive months over 12 months. The annual risk of European canker development was represented by the maximum risk index value for 2 months combined. The membership function parameters were adjusted iteratively to achieve a specified level of risk at Talca (Chile), Loughgall (Northern Ireland), East Malling (UK), and Sebastopol (USA), where European canker risk was known. The rule-based model was validated with data collected from Canada, Ecuador, Denmark, Germany, Norway, Poland, Sweden, the Netherlands, New Zealand, and the Pacific Northwest (USA), where European canker has been reported to occur. In these validation areas, the model's risk prediction agreed with reports of disease occurrence. The rule-based model also predicted high risk areas more reliably than the climate matching model, CLIMEX, which relies on correlations between the spatial distribution of a species and climatic conditions. The combination of a climatic rule and fuzzy sets could be used for other applications where prediction of the geographic distribution of organisms is required for

  8. Systemic Infection of Maize, Sorghum, Rice, and Beet Seedlings with Fumonisin-Producing and Nonproducing Fusarium verticillioides Strains

    PubMed Central

    Dastjerdi, Raana; Karlovsky, Petr

    2015-01-01

    Two fumonisin-nonproducing strains of Fusarium verticillioides and their fumonisin producing progenitors were tested for aggressiveness toward maize, sorghum, rice, and beetroot seedlings grown under greenhouse conditions. None of the plants showed obvious disease symptoms after root dip inoculation. Fungal biomass was determined by species-specific real-time PCR. No significant (P = 0.05) differences in systemic colonization were detected between the wild type strains and mutants not producing fumonisins. F. verticillioides was not detected in any of the non-inoculated control plants. The fungus grew from roots to the first two internodes/leaves of maize, rice and beet regardless of fumonisin production. The systemic growth of F. verticillioides in sorghum was limited. The results showed that fumonisin production was not required for the infection of roots of maize, rice and beet by F. verticillioides. PMID:26672472

  9. Biocontrol of tomato plant diseases caused by Fusarium solani using a new isolated Aspergillus tubingensis CTM 507 glucose oxidase.

    PubMed

    Kriaa, Mouna; Hammami, Inès; Sahnoun, Mouna; Azebou, Manel Cheffi; Triki, Mohamed Ali; Kammoun, Radhouane

    2015-10-01

    The present study focuses on the potential of glucose oxidase (GOD) as a promising biocontrol agent for fungal plant pathogens. In fact, a new GOD producing fungus was isolated and identified as an Aspergillus tubingensis. GOD (125 AU) has been found to inhibit Fusarium solani growth and spore production. Indeed, GOD caused the reduction of spores, the formation of chlamydospores, the induction of mycelial cords and the vacuolization of mycelium. In vivo assays, GOD acted as a curative treatment capable of protecting the tomato plants against F. solani diseases. In fact, the incidence was null in the curative treatment with GOD and it is around 45% for the preventive treatment. The optimization of media composition and culture conditions led to a 2.6-fold enhancement in enzyme activity, reaching 81.48U/mL. This study has demonstrated that GOD is a potent antifungal agent that could be used as a new biofungicide to protect plants from diseases.

  10. Molecular and pathological characterization of Fusarium solani species complex infection in the head and lateral line system of Sphyrna lewini.

    PubMed

    Pirarat, Nopadon; Sahatrakul, Komsil; Lacharoje, Sitthichok; Lombardini, Eric; Chansue, Nantarika; Techangamsuwan, Somporn

    2016-08-09

    A severe fungal infection affecting the head and lateral line system was diagnosed in 7 captive scalloped hammerhead sharks Sphyrna lewini in an aquarium in Thailand. Extensive and severe necrotizing cellulitis was consistently observed microscopically along the cephalic and lateral line canals in conjunction with positive fungal cultures for Fusarium sp. Molecular phylogenetic analysis was performed from 3 isolates based on the nucleotide sequences containing internally transcribed spacer (ITS) and a portion of 5.8S and 28S rDNA. The fungus was highly homologous (100%) and closely related to F. solani species complex 2 (FSSC 2), which belongs to Clade 3 of the FSSC. Our results illustrate the histopathological findings and expand upon our knowledge of the prevalence of invasive fusariosis in the head and lateral line system of hammerhead sharks.

  11. Pathogenicity of Fusarium semitectum against crop pests and its biosafety to non-target organisms.

    PubMed

    Mikunthan, G; Manjunatha, M

    2006-01-01

    Microbial control is receiving more attention, since these alternative tactics, compared to chemical control methods, are energy saving, non polluting, ecologically sound and sustainable. A mycopathogen, Fusarium semitectum Berk. and Rav. (ARSEF 7233) was isolated from diseased cadavers of aphid (Aphis gossypii) and cultured in Saboraud Maltose Agar supplemented with Yeast extract medium (SMAY). Being isolated first time from the chilli ecosystem its potential was evaluated. Experiments were conducted to understand its pathogenicity against crop pests as well as to ensure its safety to non target organisms such as silk worm (Bombyx mor), honey bee (Apis indica) and earthworm (Eisenia foetida). A paper-thrips-paper sandwich method for thrips and detached-leaf bioassay method for mites were used. Test insects and mites either reared in laboratory or obtained from the field were topically applied with spore suspension of F. semitectum (1x10(9) spores/ml). Mortality was recorded and dead animals were surface sterilized with 0.5% NaOCl and placed in SMAY medium to confirm pathogenicity. Mulberry leaves sprayed with the fungal suspension were fed to larvae of B. mori and reared. Newly emerged A. indica were topically applied with fungus. The fungus grown in cow dung for two weeks was used to assess the composting ability of E. foetida. F. semitectum produced mycosis and caused mortality to sucking pests such as chilli thrips (Scirtothrips dorsalis), broad mite (Polyphagotarsonemus latus), sugarcane wooly aphid (Ceratavacuna lanigera), spiraling whitefly (Aleyrodicus disperses), whitefly (Bemisia tabaci, A. gossypii and coconut mite (Aceria guerroronis). The fungus did not cause mortality on larvae of lepidopteran insect pests and ladybird beetle (Menochilus sexmaculatus), predatory mite (Amblysius ovalis) and larval parasitoid (Goniozus nephantidis). F. semitectum failed to infect the larvae of B. mori and newly emerged A. indica and its brood. The mycopathogen had no

  12. Variations in grain lipophilic phytochemicals, proteins and resistance to Fusarium spp. growth during grain storage as affected by biological plant protection with Aureobasidium pullulans (de Bary).

    PubMed

    Wachowska, Urszula; Tańska, Małgorzata; Konopka, Iwona

    2016-06-16

    Modern agriculture relies on an integrated approach, where chemical treatment is reduced to a minimum and replaced by biological control that involves the use of active microorganisms. The effect of the antagonistic yeast-like fungus Aureobasidium pullulans on proteins and bioactive compounds (alkylresorcinols, sterols, tocols and carotenoids) in winter wheat grain and on the colonization of wheat kernels by fungal microbiota, mainly Fusarium spp. pathogens, was investigated. Biological treatment contributed to a slight increase contents of tocols, alkylresorcinols and sterols in grain. At the same time, the variation of wheat grain proteins was low and not significant. Application of A. pullulans enhanced the natural yeast colonization after six months of grain storage and inhibited growth of F. culmorum pathogens penetrating wheat kernel. This study demonstrated that an integrated approach of wheat grain protection with the use of the yeast-like fungus A. pullulans reduced kernel colonization by Fusarium spp. pathogens and increased the content of nutritionally beneficial phytochemicals in wheat grain without a loss of gluten proteins responsible for baking value.

  13. Assessment of inhibitory potential of essential oils on natural mycoflora and Fusarium mycotoxins production in wheat

    PubMed Central

    2013-01-01

    Background In the last years essential oils from different plants were used in the prevention of fungi and mycotoxins accumulation in cereals. The most attractive aspect derived from using of essential oils as seed grains protectants is due to their non-toxicity. This study was focused on assessment the inhibitory effect of some essential oils: Melissa officinalis (O1), Salvia officinalis (O2), Coriandrum sativum (O3), Thymus vulgaris (O4) Mentha piperita (O5) and Cinnamomum zeylanicum (O6) against natural mycoflora and Fusarium mycotoxins production correlated with their antioxidants properties. Results All essential oils showed inhibitory effect on fungal contamination of wheat seeds. This ability was dose-dependent. The highest inhibitory effect on Fusarium and Aspergillus fungi was recorded after 5 days of treatment. Fungi such as yeast (Pichia, Saccharomyces and Hyphopichia) were predominantly on seeds mycoflora after 22 days. Each treatment had a selective inhibitory effect on frequency of fungus genera. After 5 days of treatment the most fungicidal effect was recorder for O4, followed by O1. In terms of essential oils effect on mycotoxins development, the best control on fumonisins (FUMO) production was recorded for O6. The antioxidant properties of essential oils decreased in order: O4 > O1 > O6 > O5 > O2 > O3. Also, our data suggested that there is a significant negative correlation between antioxidant properties and seed contamination index (SCI), but there was not recorded a good correlation between antioxidant properties and FUMO content. Conclusions Based on proven antifungal and antimycotoxin effects as well as their antioxidant properties, the essential oils could be recommended as natural preservatives for stored cereals. The highest inhibition of fungal growth was noted after 5 days of treatment and decreased after 22 days. PMID:23409841

  14. Bacterial endophytes from wild maize suppress Fusarium graminearum in modern maize and inhibit mycotoxin accumulation

    PubMed Central

    Mousa, Walaa K.; Shearer, Charles R.; Limay-Rios, Victor; Zhou, Ting; Raizada, Manish N.

    2015-01-01

    Wild maize (teosinte) has been reported to be less susceptible to pests than their modern maize (corn) relatives. Endophytes, defined as microbes that inhabit plants without causing disease, are known for their ability to antagonize plant pests and pathogens. We hypothesized that the wild relatives of modern maize may host endophytes that combat pathogens. Fusarium graminearum is the fungus that causes Gibberella Ear Rot (GER) in modern maize and produces the mycotoxin, deoxynivalenol (DON). In this study, 215 bacterial endophytes, previously isolated from diverse maize genotypes including wild teosintes, traditional landraces and modern varieties, were tested for their ability to antagonize F. graminearum in vitro. Candidate endophytes were then tested for their ability to suppress GER in modern maize in independent greenhouse trials. The results revealed that three candidate endophytes derived from wild teosintes were most potent in suppressing F. graminearum in vitro and GER in a modern maize hybrid. These wild teosinte endophytes could suppress a broad spectrum of fungal pathogens of modern crops in vitro. The teosinte endophytes also suppressed DON mycotoxin during storage to below acceptable safety threshold levels. A fourth, less robust anti-fungal strain was isolated from a modern maize hybrid. Three of the anti-fungal endophytes were predicted to be Paenibacillus polymyxa, along with one strain of Citrobacter. Microscopy studies suggested a fungicidal mode of action by all four strains. Molecular and biochemical studies showed that the P. polymyxa strains produced the previously characterized anti-Fusarium compound, fusaricidin. Our results suggest that the wild relatives of modern crops may serve as a valuable reservoir for endophytes in the ongoing fight against serious threats to modern agriculture. We discuss the possible impact of crop evolution and domestication on endophytes in the context of plant defense. PMID:26500660

  15. Risk Levels of Invasive Fusarium oxysporum f. sp. in Areas Suitable for Date Palm (Phoenix dactylifera) Cultivation under Various Climate Change Projections

    PubMed Central

    Shabani, Farzin; Kumar, Lalit

    2013-01-01

    Global climate model outputs involve uncertainties in prediction, which could be reduced by identifying agreements between the output results of different models, covering all assumptions included in each. Fusarium oxysporum f.sp. is an invasive pathogen that poses risk to date palm cultivation, among other crops. Therefore, in this study, the future distribution of invasive Fusarium oxysporum f.sp., confirmed by CSIRO-Mk3.0 (CS) and MIROC-H (MR) GCMs, was modeled and combined with the future distribution of date palm predicted by the same GCMs, to identify areas suitable for date palm cultivation with different risk levels of invasive Fusarium oxysporum f.sp., for 2030, 2050, 2070 and 2100. Results showed that 40%, 37%, 33% and 28% areas projected to become highly conducive to date palm are under high risk of its lethal fungus, compared with 37%, 39%, 43% and 42% under low risk, for the chosen years respectively. Our study also indicates that areas with marginal risk will be limited to 231, 212, 186 and 172 million hectares by 2030, 2050, 2070 and 2100. The study further demonstrates that CLIMEX outputs refined by a combination of different GCMs results of different species that have symbiosis or parasite relationship, ensure that the predictions become robust, rather than producing hypothetical findings, limited purely to publication. PMID:24340100

  16. Molecular Characterization of Fusarium oxysporum and Fusarium commune Isolates from a Conifer Nursery.

    PubMed

    Stewart, Jane E; Kim, Mee-Sook; James, Robert L; Dumroese, R Kasten; Klopfenstein, Ned B

    2006-10-01

    ABSTRACT Fusarium species can cause severe root disease and damping-off in conifer nurseries. Fusarium inoculum is commonly found in most container and bareroot nurseries on healthy and diseased seedlings, in nursery soils, and on conifer seeds. Isolates of Fusarium spp. can differ in virulence; however, virulence and colony morphology are not correlated. Forty-one isolates of Fusarium spp., morphologically indistinguishable from F. oxysporum, were collected from nursery samples (soils, healthy seedlings, and diseased seedlings). These isolates were characterized by amplified fragment length polymorphism (AFLP) and DNA sequencing of nuclear rDNA (internal transcribed spacer including 5.8S rDNA), mitochon-drial rDNA (small subunit [mtSSU]), and nuclear translation elongation factor 1-alpha. Each isolate had a unique AFLP phenotype. Out of 121 loci, 111 (92%) were polymorphic; 30 alleles were unique to only highly virulent isolates and 33 alleles were unique to only isolates nonpathogenic on conifers. Maximum parsimony and Bayesian analyses of DNA sequences from all three regions and the combined data set showed that all highly virulent isolates clearly separated into a common clade that contained F. commune, which was recently distinguished from its sister taxon, F. oxysporum. Interestingly, all but one of the nonpathogenic isolates grouped into a common clade and were genetically similar to F. oxysporum. The AFLP cladograms had similar topologies when compared with the DNA-based phylograms. Although all tested isolates were morphologically indistinguishable from F. oxysporum based on currently available monographs, some morphological traits can be plastic and unreliable for identification of Fusarium spp. We consider the highly virulent isolates to be F. commune based on strong genetic evidence. To our knowledge, this is the first reported evidence that shows F. commune is a cause of Fusarium disease (root rot and dampingoff) on Douglas-fir seedlings. Furthermore

  17. Transformation of sweet orange [Citrus sinensis (L.) Osbeck] with pthA-nls for acquiring resistance to citrus canker disease.

    PubMed

    Yang, Li; Hu, Chunhua; Li, Na; Zhang, Jiayin; Yan, Jiawen; Deng, Ziniu

    2011-01-01

    The COOH terminal of pthA encoding three nuclear localizing signals (NLS) was amplified by polymerase chain reaction (PCR) from the plasmid of Xanthomonas axonopodis pv. citri, the pathogen of citrus canker disease. Then the sense and antisense strands of the nls were cloned into pBI121 vector. pthA-nls driven by the CaMV35 s promoter was transferred into sweet orange via Agrobacterium -mediated transformation. Successful integration was confirmed by PCR and Southern blotting, and 12 sense-nls (nls (+)) and 9 antisense-nls (nls (-)) transgenic clones were obtained. The expression of nls fragment was analyzed by RT-PCR, Real time q-PCR and Western blotting, in which the specific NLS protein was detected only in nls (+) transgenic clones. In an in vitro assay, when pin-puncture inoculation was performed with 2.5 × 10(7) cfu/ml of bacterial solution, the nls (+) transgenic clones showed no typical lesion development, while typical symptoms were observed in the wild types and the nls (-) transgenic clones. In vivo assay results indicated that the nls (+) transgenic clones showed less disease incidence, in comparison with the wild types and the nls (-) transgenic clones, when pin-puncture inoculation was performed with 10(4)-10(5) cfu/ml. The minimum disease incidence was 23.3% for 'Sucarri' sweet orange and 33.3% for 'Bingtang' sweet orange. When 10(4)-10(7) cfu/ml of pathogen was spray inoculated, the nls (+) transgenic clones did not show any symptom, and even the concentration raised to 10(9) cfu/ml, the disease incidence was 20-80%, while the wild types and the nls (-) transgenic clones had 100% disease development with whatever concentration of inoculum. Two transgenic clones were confirmed to be resistant to citrus canker disease in the repeated inoculation. The results suggested that the transformation of nls sense strands may offer an effective way to acquire resistance to citrus canker disease.

  18. Volatile Substances Produced by Fusarium oxysporum from Coffee Rhizosphere and Other Microbes affect Meloidogyne incognita and Arthrobotrys conoides

    PubMed Central

    Freire, E. S.; Campos, V. P.; Pinho, R. S. C.; Oliveira, D. F.; Faria, M. R.; Pohlit, A. M.; Noberto, N. P.; Rezende, E. L.; Pfenning, L. H.; Silva, J. R. C.

    2012-01-01

    Microorganisms produce volatile organic compounds (VOCs) which mediate interactions with other organisms and may be the basis for the development of new methods to control plant-parasitic nematodes that damage coffee plants. In the present work, 35 fungal isolates were isolated from coffee plant rhizosphere, Meloidogyne exigua eggs and egg masses. Most of the fungal isolates belonged to the genus Fusarium and presented in vitro antagonism classified as mutual exclusion and parasitism against the nematode-predator fungus Arthrobotrys conoides (isolated from coffee roots). These results and the stronger activity of VOCs against this fungus by 12 endophytic bacteria may account for the failure of A. conoides to reduce plant-parasitic nematodes in coffee fields. VOCs from 13 fungal isolates caused more than 40% immobility to Meloidogyne incognita second stage juveniles (J2), and those of three isolates (two Fusarium oxysporum isolates and an F. solani isolate) also led to 88-96% J2 mortality. M. incognita J2 infectivity decreased as a function of increased exposure time to F. oxysporum isolate 21 VOCs. Gas chromatography-mass spectrometry (GC-MS) analysis lead to the detection of 38 VOCs produced by F. oxysporum is. 21 culture. Only five were present in amounts above 1% of the total: dioctyl disulfide (it may also be 2-propyldecan-1-ol or 1-(2-hydroxyethoxy) tridecane); caryophyllene; 4-methyl-2,6-di-tert-butylphenol; and acoradiene. One of them was not identified. Volatiles toxic to nematodes make a difference among interacting microorganisms in coffee rhizosphere defining an additional attribute of a biocontrol agent against plant-parasitic nematodes. PMID:23482720

  19. ISOLATION AND IDENTIFICATION OF AN ENDOPHYTIC FUNGUS PRODUCING PACLITAXEL FROM TAXUS WALLICHIANA VAR MAIREI.

    PubMed

    Zaiyou, Jian; Hongsheng, Wang; Ning, Wang; Li, Meng; Guifang, Xu

    2015-12-01

    The objective of this study was to isolate endophytic fungi producing paclitaxel from yew for the purpose of paclitaxel manufacture. Surface sterilized bark of Taxus wallichiana var. mairei was used as source material and potato dextrose agar culture medium was used in isolation of endophytic fungi. Fungal cultures were extracted with a mixture of chloroform / methanol (1:1, v/v) and the paclitaxel in the extracts was determined and authenticated with LC-MS. An endophytic fungus that produced paclitaxel was identified by ITS rDNA and 26S D1/D2 rDNA sequencing. The results showed that a total of 435 endophytic fungal strains were isolated from T. wallichiana var. mairei and purified. Only one of these strains produced paclitaxel and it belongs to Fusarium. The paclitaxel productivity in whole PDB culture and that in spent culture medium from this strain is 0.0153 mg/L and 0.0119 mg/L respectively. The paclitaxel content in dry mycelium is 0.27 mg/kg. This isolated endophytic fungus produced paclitaxel at a considerable level and shows potentiality as a producing strain for paclitaxel manufacture after strain improvement.

  20. Active pharmaceutical ingredient (api) from an estuarine fungus, Microdochium nivale (Fr.).

    PubMed

    Bhosale, S H; Patil, K B; Parameswaran, P S; Naik, C G; Jagtap, T G

    2011-09-01

    Various marine habitats sustain variety of bio-sources of ecological and biotech potentials. Pharmaceutical potential compound Cyclosporine A was reported from marine fungus Microdochium nivale associated with Porteresia coarctata, a marine salt marsh grass from mangrove environment distributed along the Central West Coast (CWC) of India. This study involves association of M. nivale with P. coarctata plant, fermentation conditions, purification of Cyclosporine A, chemical characterization etc. Its antifungal inhibition and MIC (Minimum inhibitory concentration) against Aspergillus strains (A. niger, A. japonicus, A. fresenii), yeasts and dermatophytes (Candida sp., Cryptococcus neoformans, Trichophyton mentagrophytes, T. tonsurans, T. violaceum, Microsporium gypsum and Fusarium sp.) were evaluated. However, the MIC against A. japonicus, C. neoformans, Candida sp. and T. tonsurans were confirmed to be as low as 12.5-25 mg disc(-1). The antifungal properties of Cyclosporine A against Aspergillus species, yeast and dermatophytes revealed that CyclosporineAwould be a potential compound for life threatening diseases caused by above fungi in both human and animals. Furthermore, we have reported herewith another source of Cyclosporin Aderived from filamentous fungus, M. nivale. occurring in marine environment.

  1. Species-Specific Detection and Identification of Fusarium Species Complex, the Causal Agent of Sugarcane Pokkah Boeng in China

    PubMed Central

    Que, Youxiong; Wang, Jihua; Comstock, Jack C.; Wei, Jinjin; McCord, Per H.; Chen, Baoshan; Chen, Rukai; Zhang, Muqing

    2014-01-01

    Background Pokkah boeng disease caused by the Fusarium species complex results in significant yield losses in sugarcane. Thus, the rapid and accurate detection and identification of the pathogen is urgently required to manage and prevent the spreading of sugarcane pokkah boeng. Methods A total of 101 isolates were recovered from the pokkah boeng samples collected from five major sugarcane production areas in China throughout 2012 and 2013. The causal pathogen was identified by morphological observation, pathogenicity test, and phylogenetic analysis based on the fungus-conserved rDNA-ITS. Species-specific TaqMan real-time PCR and conventional PCR methods were developed for rapid and accurate detection of the causal agent of sugarcane pokkah boeng. The specificity and sensitivity of PCR assay were also evaluated on a total of 84 isolates of Fusarium from China and several isolates from other fungal pathogens of Sporisorium scitamineum and Phoma sp. and sugarcane endophyte of Acremonium sp. Result Two Fusarium species (F. verticillioides and F. proliferatum) that caused sugarcane pokahh boeng were identified by morphological observation, pathogenicity test, and phylogenetic analysis. Species-specific TaqMan PCR and conventional PCR were designed and optimized to target their rDNA-ITS regions. The sensitivity of the TaqMan PCR was approximately 10 pg of fungal DNA input, which was 1,000-fold over conventional PCR, and successfully detected pokkah boeng in the field-grown sugarcane. Conclusions/Significance This study was the first to identify two species, F. verticillioides and F. proliferatum, that were causal pathogens of sugarcane pokkah boeng in China. It also described the development of a species-specific PCR assay to detect and confirm these pathogens in sugarcane plants from mainland China. This method will be very useful for a broad range of research endeavors as well as the regulatory response and management of sugarcane pokkah boeng. PMID:25141192

  2. Trichoderma harzianum and Glomus intraradices modify the hormone disruption induced by Fusarium oxysporum infection in melon plants.

    PubMed

    Martínez-Medina, Ainhoa; Pascual, Jose Antonio; Pérez-Alfocea, Francisco; Albacete, Alfonso; Roldán, Antonio

    2010-07-01

    The plant hormones salicylic acid (SA), jasmonic acid (JA), ethylene (ET), and abscisic acid (ABA) are known to play crucial roles in plant disease and pest resistance. Changes in the concentrations of these plant hormones in melon plant shoots, as a consequence of the interaction between the plant, the pathogen Fusarium oxysporum, the antagonistic microorganism Trichoderma harzianum, and the arbuscular mycorrhizal fungus Glomus intraradices were investigated. Attack by F. oxysporum activated a defensive response in the plant, mediated by the plant hormones SA, JA, ET, and ABA, similar to the one produced by T. harzianum. When inoculated with the pathogen, both T. harzianum and G. intraradices attenuated the plant response mediated by the hormones ABA and ET elicited by the pathogen attack. T. harzianum was also able to attenuate the SA-mediated response. In the three-way interaction (F. oxysporum-T. harzianum-G. intraradices), although a synergistic effect in reducing disease incidence was found, no synergistic effect on the modulation of the hormone disruption induced by the pathogen was observed. These results suggest that the induction of plant basal resistance and the attenuation of the hormonal disruption caused by F. oxysporum are both mechanisms by which T. harzianum can control Fusarium wilt in melon plants; while the mechanisms involving G. intraradices seem to be independent of SA and JA signaling.

  3. Down-regulation of Fusarium oxysporum endogenous genes by Host-Delivered RNA interference enhances disease resistance

    NASA Astrophysics Data System (ADS)

    Hu, Zongli; Parekh, Urvi; Maruta, Natsumi; Trusov, Yuri; Botella, Jimmy

    2015-01-01

    Fusarium oxysporum is a devastating pathogen causing extensive yield losses in a variety of crops and development of sustainable, environmentally friendly methods to improve crop resistance is crucial. We have used Host-Derived RNA interference (HD-RNAi) technology to partially silence three different genes (FOW2, FRP1 and OPR) in the hemi-biotrophic fungus Fusarium oxysporum f. sp. conglutinans. Expression of double stranded RNA molecules targeting fungal pathogen genes was achieved in a number of transgenic Arabidopsis lines. F. oxysporum infecting the transgenic lines displayed substantially reduced mRNA levels on all three targeted genes, with an average of 75%, 83% and 72% reduction for FOW2, FRP1 and OPR respectively. The silencing of pathogen genes had a clear positive effect on the ability of the transgenic lines to fight infection. All transgenic lines displayed enhanced resistance to F. oxysporum with delayed disease symptom development, especially FRP1 and OPR lines. Survival rates after fungal infection were higher in the transgenic lines compared to control wild type plants which consistently showed survival rates of 10%, with FOW2 lines showing 25% survival; FRP1 lines 30-50% survival and FOW2 between 45-70% survival. The down-regulation effect was specific for the targeted genes without unintended effects in related genes. In addition to producing resistant crops, HD-RNAi can provide a useful tool to rapidly screen candidate fungal pathogenicity genes without the need to produce fungal knockout mutants.

  4. Influence of Butylated Hydroxyanisole on the Growth, Hyphal Morphology, and the Biosynthesis of Fumonisins in Fusarium proliferatum

    PubMed Central

    Li, Taotao; Jian, Qijie; Chen, Feng; Wang, Yong; Gong, Liang; Duan, Xuewu; Yang, Bao; Jiang, Yueming

    2016-01-01

    Fusarium proliferatum as a common fungus pathogen in foods can produce toxic fumonisins, which can cause animal diseases and increase risks of human cancers. On contrary, butylated hydroxyanisole (BHA) as a synthetic antioxidant offers a clue for preventing growth of fungal species and inhibiting production of mycotoxins. Unfortunately, information of the inhibitory mechanism of BHA on Fusarium species is still limited. In this study, influence of BHA treatment on growth and inhibition of fumonisin production in relation to the expression of the fumonisin biosynthesis-related genes of the F. proliferatum ZYF was investigated, which revealed that BHA had a negative influence on growth and fumonisin production of F. proliferatum. To further elucidate the mechanism of BHA on the growth of F. proliferatum, scanning electron microscopy (SEM) and transmission electron microscopy (TEM) were used to examine the F. proliferatum hyphae. The BHA treatment induced the loss of cytoplasm and cellular constituents, as well as distortion of mycelia, but it did not directly degrade the fumonisin. Furthermore, the BHA treatment markedly inhibited the expressions of FUM1 (a polyketide synthase encoding gene) and FUM8 (an aminotransferase encoding gene) genes, which resulted in the depression of metabolic pathway of F. proliferatum. The transcriptional analyses of the FUM1 and FUM8 genes confirmed a correlation between the fumonisin production and its gene expression. This study provided some insights into mechanisms of production of fumonisin and feasible prevention to reduce fumonisin contamination in favor of human and animal health. PMID:27468276

  5. Identification and evaluation of two diagnostic markers linked to Fusarium wilt resistance (race 4) in banana (Musa spp.).

    PubMed

    Wang, Wei; Hu, Yulin; Sun, Dequan; Staehelin, Christian; Xin, Dawei; Xie, Jianghui

    2012-01-01

    Fusarium wilt caused by the fungus Fusarium oxysporum f. sp. cubense race 4 (FOC4) results in vascular tissue damage and ultimately death of banana (Musa spp.) plants. Somaclonal variants of in vitro micropropagated banana can hamper success in propagation of genotypes resistant to FOC4. Early identification of FOC4 resistance in micropropagated banana plantlets is difficult, however. In this study, we identified sequence-characterized amplified region (SCAR) markers of banana associated with resistance to FOC4. Using pooled DNA from resistant or susceptible genotypes and 500 arbitrary 10-mer oligonucleotide primers, 24 random amplified polymorphic DNA (RAPD) products were identified. Two of these RAPD markers were successfully converted to SCAR markers, called ScaU1001 (GenBank accession number HQ613949) and ScaS0901 (GenBank accession number HQ613950). ScaS0901 and ScaU1001 could be amplified in FOC4-resistant banana genotypes ("Williams 8818-1" and Goldfinger), but not in five tested banana cultivars susceptible to FOC4. The two SCAR markers were then used to identify a somaclonal variant of the genotype "Williams 8818-1", which lost resistance to FOC4. Hence, the identified SCAR markers can be applied for a rapid quality control of FOC4-resistant banana plantlets immediately after the in vitro micropropagation stage. Furthermore, ScaU1001 and ScaS0901 will facilitate marker-assisted selection of new banana cultivars resistant to FOC4.

  6. An Evaluation Method for the Suppression of Pathogenic Fusarium oxysporum by Soil Microorganisms Using the Dilution Plate Technique

    PubMed Central

    Mitsuboshi, Masahiro; Kioka, Yuuzou; Noguchi, Katsunori; Asakawa, Susumu

    2016-01-01

    Soil-borne diseases caused by pathogenic microorganisms are one of the main factors responsible for the decline in crop yields in farmlands. Pathogenic Fusarium oxysporum causes serious damage to various crops, and, thus, a feasible diagnostic method for soil-borne diseases is required. We herein examined a simple method to evaluate the suppressiveness of soil microorganisms against a pathogen by co-cultivating indigenous soil microorganisms and a pathogenic fungus (F. oxysporum f. sp. spinaciae). We inoculated F. oxysporum onto the center of agar medium plates mixed with a dilution series of a suspension of organic fertilizers or soil. After an approximately one-week cultivation, the growth degree of F. oxysporum was estimated based on the size of the colonies that formed on the plates. The growth degree of F. oxysporum significantly differed among the organic fertilizers tested, indicating the usefulness of the method for evaluating suppressiveness by organic fertilizers. Differences in the growth degrees of F. oxysporum were associated with the incidence of disease in spinach on soil treated with organic fertilizers and inoculated with a pathogenic F. oxysporum strain. These results suggested that this method provides some useful information on the suppressiveness of organic fertilizers and soil against Fusarium wilt. PMID:27558588

  7. Members of Gammaproteobacteria as indicator species of healthy banana plants on Fusarium wilt-infested fields in Central America

    PubMed Central

    Köberl, Martina; Dita, Miguel; Martinuz, Alfonso; Staver, Charles; Berg, Gabriele

    2017-01-01

    Culminating in the 1950’s, bananas, the world’s most extensive perennial monoculture, suffered one of the most devastating disease epidemics in history. In Latin America and the Caribbean, Fusarium wilt (FW) caused by the soil-borne fungus Fusarium oxysporum f. sp. cubense (FOC), forced the abandonment of the Gros Michel-based export banana industry. Comparative microbiome analyses performed between healthy and diseased Gros Michel plants on FW-infested farms in Nicaragua and Costa Rica revealed significant shifts in the gammaproteobacterial microbiome. Although we found substantial differences in the banana microbiome between both countries and a higher impact of FOC on farms in Costa Rica than in Nicaragua, the composition especially in the endophytic microhabitats was similar and the general microbiome response to FW followed similar rules. Gammaproteobacterial diversity and community members were identified as potential health indicators. Healthy plants revealed an increase in potentially plant-beneficial Pseudomonas and Stenotrophomonas, while diseased plants showed a preferential occurrence of Enterobacteriaceae known for their plant-degrading capacity. Significantly higher microbial rhizosphere diversity found in healthy plants could be indicative of pathogen suppression events preventing or minimizing disease expression. This first study examining banana microbiome shifts caused by FW under natural field conditions opens new perspectives for its biological control. PMID:28345666

  8. An Evaluation Method for the Suppression of Pathogenic Fusarium oxysporum by Soil Microorganisms Using the Dilution Plate Technique.

    PubMed

    Mitsuboshi, Masahiro; Kioka, Yuuzou; Noguchi, Katsunori; Asakawa, Susumu

    2016-09-29

    Soil-borne diseases caused by pathogenic microorganisms are one of the main factors responsible for the decline in crop yields in farmlands. Pathogenic Fusarium oxysporum causes serious damage to various crops, and, thus, a feasible diagnostic method for soil-borne diseases is required. We herein examined a simple method to evaluate the suppressiveness of soil microorganisms against a pathogen by co-cultivating indigenous soil microorganisms and a pathogenic fungus (F. oxysporum f. sp. spinaciae). We inoculated F. oxysporum onto the center of agar medium plates mixed with a dilution series of a suspension of organic fertilizers or soil. After an approximately one-week cultivation, the growth degree of F. oxysporum was estimated based on the size of the colonies that formed on the plates. The growth degree of F. oxysporum significantly differed among the organic fertilizers tested, indicating the usefulness of the method for evaluating suppressiveness by organic fertilizers. Differences in the growth degrees of F. oxysporum were associated with the incidence of disease in spinach on soil treated with organic fertilizers and inoculated with a pathogenic F. oxysporum strain. These results suggested that this method provides some useful information on the suppressiveness of organic fertilizers and soil against Fusarium wilt.

  9. Pathogenicity of seed transmittedFusarium spp. to triticale seedlings.

    PubMed

    Arseniuk, E; Scharen, A L; Czembor, H J

    1991-09-01

    In the conducted studies 13 species ofFusarium were isolated into pure culture from triticale seed. Their pathogenicity was assessed under laboratory and greenhouse conditions. Most of the species studied were highly pathogenic to the first leaf see-dlings of triticale 'Grado' and 'Lasko' under both sets of conditions. It was shown, that seed-transmitted Fusarium spp. considerably reduced the ability of seeds to germinate and incited seedling blight. On average, triticale 'Lasko' was more resistant toFusarium spp. than 'Grado', but in some instances a reverse reaction was observed.

  10. Entomology: A Bee Farming a Fungus.

    PubMed

    Oldroyd, Benjamin P; Aanen, Duur K

    2015-11-16

    Farming is done not only by humans, but also by some ant, beetle and termite species. With the discovery of a stingless bee farming a fungus that provides benefits to its larvae, bees can be added to this list.

  11. Environmental Influences on Pigeonpea-Fusarium udum Interactions and Stability of Genotypes to Fusarium Wilt

    PubMed Central

    Sharma, Mamta; Ghosh, Raju; Telangre, Rameshwar; Rathore, Abhishek; Saifulla, Muhammad; Mahalinga, Dayananda M.; Saxena, Deep R.; Jain, Yogendra K.

    2016-01-01

    Fusarium wilt (Fusarium udum Butler) is an important biotic constraint to pigeonpea (Cajanus cajan L.) production worldwide. Breeding for fusarium wilt resistance continues to be an integral part of genetic improvement of pigeonpea. Therefore, the study was aimed at identifying and validating resistant genotypes to fusarium wilt and determining the magnitude of genotype × environment (G × E) interactions through multi-environment and multi-year screening. A total of 976 genotypes including germplasm and breeding lines were screened against wilt using wilt sick plot at Patancheru, India. Ninety two genotypes resistant to wilt were tested for a further two years using wilt sick plot at Patancheru. A Pigeonpea Wilt Nursery (PWN) comprising of 29 genotypes was then established. PWN was evaluated at nine locations representing different agro-climatic zones of India for wilt resistance during two crop seasons 2007/08 and 2008/09. Genotypes (G), environment (E), and G × E interactions were examined by biplot which partitioned the main effect into G, E, and G × E interactions with significant levels (p ≤ 0.001) being obtained for wilt incidence. The genotype contributed 36.51% of resistance variation followed by the environment (29.32%). A GGE biplot integrated with a boxplot and multiple comparison tests enabled us to identify seven stable genotypes (ICPL 20109, ICPL 20096, ICPL 20115, ICPL 20116, ICPL 20102, ICPL 20106, and ICPL 20094) based on their performance across diverse environments. These genotypes have broad based resistance and can be exploited in pigeonpea breeding programs. PMID:27014287

  12. Environmental Influences on Pigeonpea-Fusarium udum Interactions and Stability of Genotypes to Fusarium Wilt.

    PubMed

    Sharma, Mamta; Ghosh, Raju; Telangre, Rameshwar; Rathore, Abhishek; Saifulla, Muhammad; Mahalinga, Dayananda M; Saxena, Deep R; Jain, Yogendra K

    2016-01-01

    Fusarium wilt (Fusarium udum Butler) is an important biotic constraint to pigeonpea (Cajanus cajan L.) production worldwide. Breeding for fusarium wilt resistance continues to be an integral part of genetic improvement of pigeonpea. Therefore, the study was aimed at identifying and validating resistant genotypes to fusarium wilt and determining the magnitude of genotype × environment (G × E) interactions through multi-environment and multi-year screening. A total of 976 genotypes including germplasm and breeding lines were screened against wilt using wilt sick plot at Patancheru, India. Ninety two genotypes resistant to wilt were tested for a further two years using wilt sick plot at Patancheru. A Pigeonpea Wilt Nursery (PWN) comprising of 29 genotypes was then established. PWN was evaluated at nine locations representing different agro-climatic zones of India for wilt resistance during two crop seasons 2007/08 and 2008/09. Genotypes (G), environment (E), and G × E interactions were examined by biplot which partitioned the main effect into G, E, and G × E interactions with significant levels (p ≤ 0.001) being obtained for wilt incidence. The genotype contributed 36.51% of resistance variation followed by the environment (29.32%). A GGE biplot integrated with a boxplot and multiple comparison tests enabled us to identify seven stable genotypes (ICPL 20109, ICPL 20096, ICPL 20115, ICPL 20116, ICPL 20102, ICPL 20106, and ICPL 20094) based on their performance across diverse environments. These genotypes have broad based resistance and can be exploited in pigeonpea breeding programs.

  13. Modifications of Xanthomonas axonopodis pv. citri lipopolysaccharide affect the basal response and the virulence process during citrus canker.

    PubMed

    Petrocelli, Silvana; Tondo, María Laura; Daurelio, Lucas D; Orellano, Elena G

    2012-01-01

    Xanthomonas axonopodis pv. citri (Xac) is the phytopathogen responsible for citrus canker, one of the most devastating citrus diseases in the world. A broad range of pathogens is recognized by plants through so-called pathogen-associated molecular patterns (PAMPs), which are highly conserved fragments of pathogenic molecules. In plant pathogenic bacteria, lipopolisaccharyde (LPS) is considered a virulence factor and it is being recognized as a PAMP. The study of the participation of Xac LPS in citrus canker establishment could help to understand the molecular bases of this disease. In the present work we investigated the role of Xac LPS in bacterial virulence and in basal defense during the interaction with host and non host plants. We analyzed physiological features of Xac mutants in LPS biosynthesis genes (wzt and rfb303) and the effect of these mutations on the interaction with orange and tobacco plants. Xac mutants showed an increased sensitivity to external stresses and differences in bacterial motilities, in vivo and in vitro adhesion and biofilm formation. Changes in the expression levels of the LPS biosynthesis genes were observed in a medium that mimics the plant environment. Xacwzt exhibited reduced virulence in host plants compared to Xac wild-type and Xacrfb303. However, both mutant strains produced a lower increase in the expression levels of host plant defense-related genes respect to the parental strain. In addition, Xac LPS mutants were not able to generate HR during the incompatible interaction with tobacco plants. Our findings indicate that the structural modifications of Xac LPS impinge on other physiological attributes and lead to a reduction in bacterial virulence. On the other hand, Xac LPS has a role in the activation of basal defense in host and non host plants.

  14. Effect of climate change on sporulation of the teleomorphs of Leptosphaeria species causing stem canker of brassicas.

    PubMed

    Kaczmarek, Joanna; Kedziora, Andrzej; Brachaczek, Andrzej; Latunde-Dada, Akinwunmi O; Dakowska, Sylwia; Karg, Grzegorz; Jedryczka, Małgorzata

    Leptosphaeria maculans and L. biglobosa are closely related sibling fungal pathogens that cause phoma leaf spotting, stem canker (blackleg) and stem necrosis of oilseed rape (Brassica napus). The disease is distributed worldwide, and it is one of the main causes of considerable decrease in seed yield and quality. Information about the time of ascospore release at a particular location provides important data for decision making in plant protection, thereby enabling fungicides to be used only when necessary and at optimal times and doses. Although the pathogens have been studied very extensively, the effect of climate change on the frequencies and distributions of their aerially dispersed primary inoculum has not been reported to date. We have collected a large dataset of spore counts from Poznan, located in central-west part of Poland, and studied the relationships between climate and the daily concentrations of airborne propagules over a period of 17 years (1998-2014). The average air temperature and precipitation for the time of development of pseudothecia and ascospore release (July-November), increased during the years under study at the rates of 0.1 °C and 6.3 mm per year. The day of the year (DOY) for the first detection of spores, as well as the date with maximum of spores, shifted from 270 to 248 DOY, and from 315 to 265 DOY, respectively. The acceleration of the former parameter by 22 days and the latter by 50 days has great influence on the severity of stem canker of oilseed rape.

  15. Analysis of miRNAs targeting transcription factors in Persicaria minor induced by Fusarium oxysporum

    NASA Astrophysics Data System (ADS)

    Samad, Abdul Fatah A.; Ali, Nazaruddin Muhammad; Ismail, Ismanizan; Murad, Abdul Munir Abdul

    2016-11-01

    A recent discovery showed small non-coding RNA known as microRNA has a crucial role in plant development and plant survival in extreme condition. In the past few years, researchers have managed to identify the various families of transcription factors that play a crucial role in regulating plant development and plant responses to stresses. This study focuses on the expression pattern of miRNA targeted transcription factor under biotic stress in a plant rich with secondary metabolite, Persicaria minor. A pathogenic fungus, Fusarium oxysporum was used in the biotic stress treatment since the previous study revealed this fungus could trigger plant defense system. Two small RNA libraries were constructed which consist of control and treated samples. In order to identify the potential target, psRobot target prediction software was used for each miRNA that shows significant change due to the infection. The result showed miR156b/c, miR172a, miR319, miR858, and miR894 were found to be targeting a wide range of transcription factors that involve in plant development and plant response towards stresses. The expression of miR156b/c and miR172 were up-regulated while the expression of miR319, miR858, and miR894 was found to be down-regulated. These results may provide a certain level of networking between those two regulatory molecules in plant genetic system under biotic stress.

  16. Nitrate Assimilation in Fusarium fujikuroi Is Controlled by Multiple Levels of Regulation.

    PubMed

    Pfannmüller, Andreas; Boysen, Jana M; Tudzynski, Bettina

    2017-01-01

    Secondary metabolite production of the phytopathogenic ascomycete fungus Fusarium fujikuroi is greatly influenced by the availability of nitrogen. While favored nitrogen sources such as glutamine and ammonium are used preferentially, the uptake and utilization of nitrate is subject to a regulatory mechanism called nitrogen metabolite repression (NMR). In Aspergillus nidulans, the transcriptional control of the nitrate assimilatory system is carried out by the synergistic action of the nitrate-specific transcription factor NirA and the major nitrogen-responsive regulator AreA. In this study, we identified the main components of the nitrate assimilation system in F. fujikuroi and studied the role of each of them regarding the regulation of the remaining components. We analyzed mutants with deletions of the nitrate-specific activator NirA, the nitrate reductase (NR), the nitrite reductase (NiR) and the nitrate transporter NrtA. We show that NirA controls the transcription of the nitrate assimilatory genes NIAD, NIIA, and NRTA in the presence of nitrate, and that the global nitrogen regulator AreA is obligatory for expression of most, but not all NirA target genes (NIAD). By transforming a NirA-GFP fusion construct into the ΔNIAD, ΔNRTA, and ΔAREA mutant backgrounds we revealed that NirA was dispersed in the cytosol when grown in the presence of glutamine, but rapidly sorted to the nucleus when nitrate was added. Interestingly, the rapid and nitrate-induced nuclear translocation of NirA was observed also in the ΔAREA and ΔNRTA mutants, but not in ΔNIAD, suggesting that the fungus is able to directly sense nitrate in an AreA- and NrtA-independent, but NR-dependent manner.

  17. Nitrate Assimilation in Fusarium fujikuroi Is Controlled by Multiple Levels of Regulation

    PubMed Central

    Pfannmüller, Andreas; Boysen, Jana M.; Tudzynski, Bettina

    2017-01-01

    Secondary metabolite production of the phytopathogenic ascomycete fungus Fusarium fujikuroi is greatly influenced by the availability of nitrogen. While favored nitrogen sources such as glutamine and ammonium are used preferentially, the uptake and utilization of nitrate is subject to a regulatory mechanism called nitrogen metabolite repression (NMR). In Aspergillus nidulans, the transcriptional control of the nitrate assimilatory system is carried out by the synergistic action of the nitrate-specific transcription factor NirA and the major nitrogen-responsive regulator AreA. In this study, we identified the main components of the nitrate assimilation system in F. fujikuroi and studied the role of each of them regarding the regulation of the remaining components. We analyzed mutants with deletions of the nitrate-specific activator NirA, the nitrate reductase (NR), the nitrite reductase (NiR) and the nitrate transporter NrtA. We show that NirA controls the transcription of the nitrate assimilatory genes NIAD, NIIA, and NRTA in the presence of nitrate, and that the global nitrogen regulator AreA is obligatory for expression of most, but not all NirA target genes (NIAD). By transforming a NirA-GFP fusion construct into the ΔNIAD, ΔNRTA, and ΔAREA mutant backgrounds we revealed that NirA was dispersed in the cytosol when grown in the presence of glutamine, but rapidly sorted to the nucleus when nitrate was added. Interestingly, the rapid and nitrate-induced nuclear translocation of NirA was observed also in the ΔAREA and ΔNRTA mutants, but not in ΔNIAD, suggesting that the fungus is able to directly sense nitrate in an AreA- and NrtA-independent, but NR-dependent manner. PMID:28352253

  18. Deciphering the Cryptic Genome: Genome-wide Analyses of the Rice Pathogen Fusarium fujikuroi Reveal Complex Regulation of Secondary Metabolism and Novel Metabolites

    PubMed Central

    Studt, Lena; Niehaus, Eva-Maria; Espino, Jose J.; Huß, Kathleen; Michielse, Caroline B.; Albermann, Sabine; Wagner, Dominik; Bergner, Sonja V.; Connolly, Lanelle R.; Fischer, Andreas; Reuter, Gunter; Kleigrewe, Karin; Bald, Till; Wingfield, Brenda D.; Ophir, Ron; Freeman, Stanley; Hippler, Michael; Smith, Kristina M.; Brown, Daren W.; Proctor, Robert H.; Münsterkötter, Martin; Freitag, Michael; Humpf, Hans-Ulrich; Güldener, Ulrich; Tudzynski, Bettina

    2013-01-01

    The fungus Fusarium fujikuroi causes “bakanae” disease of rice due to its ability to produce gibberellins (GAs), but it is also known for producing harmful mycotoxins. However, the genetic capacity for the whole arsenal of natural compounds and their role in the fungus' interaction with rice remained unknown. Here, we present a high-quality genome sequence of F. fujikuroi that was assembled into 12 scaffolds corresponding to the 12 chromosomes described for the fungus. We used the genome sequence along with ChIP-seq, transcriptome, proteome, and HPLC-FTMS-based metabolome analyses to identify the potential secondary metabolite biosynthetic gene clusters and to examine their regulation in response to nitrogen availability and plant signals. The results indicate that expression of most but not all gene clusters correlate with proteome and ChIP-seq data. Comparison of the F. fujikuroi genome to those of six other fusaria revealed that only a small number of gene clusters are conserved among these species, thus providing new insights into the divergence of secondary metabolism in the genus Fusarium. Noteworthy, GA biosynthetic genes are present in some related species, but GA biosynthesis is limited to F. fujikuroi, suggesting that this provides a selective advantage during infection of the preferred host plant rice. Among the genome sequences analyzed, one cluster that includes a polyketide synthase gene (PKS19) and another that includes a non-ribosomal peptide synthetase gene (NRPS31) are unique to F. fujikuroi. The metabolites derived from these clusters were identified by HPLC-FTMS-based analyses of engineered F. fujikuroi strains overexpressing cluster genes. In planta expression studies suggest a specific role for the PKS19-derived product during rice infection. Thus, our results indicate that combined comparative genomics and genome-wide experimental analyses identified novel genes and secondary metabolites that contribute to the evolutionary success of F

  19. Evaluating Fumonisin Gene Expression in Fusarium verticillioides.

    PubMed

    Scala, Valeria; Visentin, Ivan; Cardinale, Francesca

    2017-01-01

    Transcript levels of key genes in a biosynthetic pathway are often taken as a proxy for metabolite production. This is the case of FUM1, encoding the first dedicated enzyme in the metabolic pathway leading to the production of the mycotoxins Fumonisins by fungal species belonging to the genus Fusarium. FUM1 expression can be quantified by different methods; here, we detail a protocol based on quantitative reverse transcriptase polymerase chain reaction (RT-qPCR), by which relative or absolute transcript abundance can be estimated in Fusaria grown in vitro or in planta. As very seldom commercial kits for RNA extraction and cDNA synthesis are optimized for fungal samples, we developed a protocol tailored for these organisms, which stands alone but can be also easily integrated with specific reagents and kits commercially available.

  20. Production of Alanine by Fusarium moniliforme

    PubMed Central

    Carito, Sebastian L.; Pisano, Michael A.

    1966-01-01

    Fusarium moniliforme grown in a chemically defined medium in submerged culture accumulated amino acids extracellularly. Alanine and glutamic acid were present in greatest amounts, with traces of glycine, lysine, threonine, and valine detectable. Increasing the glucose and urea concentrations of the medium increased yields of alanine. Further increases in alanine production occurred with elevated levels of mineral salts in the medium, whereas the addition of a vitamin mixture proved to be inhibitory. Chemical changes resulting from the growth of F. moniliforme in the final fermentation medium disclosed maximal alanine production, mycelial weight, and glucose consumption after 72 hr of incubation at 28.5 C. Total soluble nitrogen, by contrast, was minimal at the same time period. The pH remained in the alkaline range throughout the fermentation. PMID:5914495

  1. Bioactive dihydronaphthoquinone derivatives from Fusarium solani.

    PubMed

    Takemoto, Kenji; Kamisuki, Shinji; Chia, Pei Thing; Kuriyama, Isoko; Mizushina, Yoshiyuki; Sugawara, Fumio

    2014-09-26

    New dihydronaphthoquinone derivatives, karuquinone A (1), karuquinone B (2), and karuquinone C (3), were isolated from a fungal culture broth of Fusarium solani. The structures were determined by interpretation of spectroscopic data (1D/2D NMR, MS, and IR). Three known compounds, javanicin (4), 2,3-dihydro-5-hydroxy-8-methoxy-2,4-dimethylnaphtho[1,2-b]furan-6,9-dione (5), and 5-hydroxydihydrofusarubin C (6), were also isolated. The six isolated compounds were tested for cytotoxicity against three human cancer cell lines and a human umbilical vein endothelial cell (HUVEC) line. Of these, karuquinone A exhibited the strongest cytotoxic activity. Karuquinone B did not affect the proliferation of the cancer cell lines but did inhibit the proliferation of HUVEC. Additionally, we demonstrated that karuquinone A induces apoptosis in cancer cells through the generation of reactive oxygen species (ROS).

  2. Genome wide transcriptome profiling of Fusarium oxysporum f sp. ciceris conidial germination reveals new insights into infection-related genes

    PubMed Central

    Sharma, Mamta; Sengupta, Anindita; Ghosh, Raju; Agarwal, Gaurav; Tarafdar, Avijit; Nagavardhini, A; Pande, Suresh; Varshney, Rajeev K

    2016-01-01

    Vascular wilt caused by Fusarium oxysporum f. sp. ciceris (Foc) is a serious disease of chickpea (Cicer arietinum L.) accounting for approximately 10–15% annual crop loss. The fungus invades the plant via roots, colonizes the xylem vessels and prevents the upward translocation of water and nutrients. Infection is initiated by conidia that invade the host tissue often by penetration of intact epidermal cells. Here, we report the characterization of the transcriptome of Foc sequenced using Illumina Hiseq technology during its conidial germination at different time points. Genome-wide expression profiling revealed that genes linked to fungal development are transcribed in successive ways. Analysis showed that Foc have large sets of germination-related genes and families of genes encoding secreted effectors, cell wall/pectin-degrading enzymes, metabolism related enzymes, transporters and peptidases. We found that metabolism related enzymes are up-regulated at early time point whereas most transporters and secondary metabolites important for tissue colonization and pathogenicity are up-regulated later as evident from the qRT-PCR. The study demonstrated that early conidial germination in Foc is accompanied by rapid shifts in gene expression that prepare the fungus for germ tube outgrowth, host cell invasion and pathogenesis. This work lays the foundation for facilitating further research towards understanding this host-pathogen interaction. PMID:27853284

  3. Shifts in banana root exudate profiles after colonization with the non-pathogenic Fusarium oxysporum strain Fo162.

    PubMed

    Kurtz, Andreas; Schouten, Alexander

    2009-01-01

    The non-pathogenic fungus Fusorium oxysporum strain Fo162 can efficiently colonize banana roots and reduce infecting by the burrowing nematode Radopholus similis. It is assumed that the fungus triggers a systemic reaction in the plant, which is affecting the biochemical composition of the root exudates and is thus causing the reduction in nematode colonization. To characterize these shifts, a continuous flow experiment was set up to collect root metabolites on a matrix (XAD-4). Based on HPLC analysis, the extracts, collected from the XAD-4, showed no differences in the composition of the root exudates between plants colonized by the endophyte and the controls. However, the accumulation of several compounds differed significantly. When these extracts were used in a bioassay with Radopholus similis none of the sample-treatment combinations had a significant attracting or repelling effect on the nematodes. This experiment shows that non-pathogenic Fusarium oxysporum strain Fo162 is able to upregulate the synthesis of at least some, so far unidentified compounds released by banana roots under hydroponic conditions. Further studies and optimization of the experimental setup are required to determine whether or not increase in metabolite concentration can affect nematode responses in vitro and ultimately in vivo.

  4. Higher Fusarium Toxin Accumulation in Grain of Winter Triticale Lines Inoculated with Fusarium culmorum as Compared with Wheat †

    PubMed Central

    Góral, Tomasz; Wiśniewska, Halina; Ochodzki, Piotr; Walentyn-Góral, Dorota

    2016-01-01

    Resistance to Fusarium head blight in 32 winter triticale and 34 winter wheat accessions was evaluated. Triticale and wheat were sown in field experiments in two locations. At the time of flowering, heads were inoculated with three Fusarium culmorum isolates. Fusarium head blight index was scored and after the harvest percentage of Fusarium damaged kernels was assessed. Grain was analysed for type B trichothecenes (deoxynivalenol and derivatives, nivalenol) and zearalenone (ZEN) content. The average Fusarium head blight indexes were 28.0% for wheat and 19.2% for triticale accessions. The percentage of Fusarium damaged kernels was also higher for wheat and came to 55.6%, while for triticale this figure was 40.2%. The average content of deoxynivalenol (DON) for wheat amounted to 11.65 mg/kg and was lower than the result for triticale which was 14.12 mg/kg. The average contents of nivalenol were similar in both cereals: 4.13 mg/kg and 5.19 mg/kg for wheat and triticale respectively. Considerable amounts of DON derivatives in the cereals were also detected. The ZEN content in the grain was 0.60 mg/kg for wheat and 0.66 mg/kg for triticale. Relationships between Fusarium head blight index, Fusarium damaged kernels and mycotoxin contents were statistically significant for wheat and mostly insignificant for triticale. Triticale proved to have less infected heads and kernels than wheat. However, the content of type B trichothecenes was higher in triticale grain than in wheat grain. PMID:27763547

  5. Genus-Specific Primers for Study of Fusarium Communities in Field Samples.

    PubMed

    Karlsson, Ida; Edel-Hermann, Véronique; Gautheron, Nadine; Durling, Mikael Brandström; Kolseth, Anna-Karin; Steinberg, Christian; Persson, Paula; Friberg, Hanna

    2015-10-30

    Fusarium is a large and diverse genus of fungi of great agricultural and economic importance, containing many plant pathogens and mycotoxin producers. To date, high-throughput sequencing of Fusarium communities has been limited by the lack of genus-specific primers targeting regions with high discriminatory power at the species level. In the present study, we evaluated two Fusarium-specific primer pairs targeting translation elongation factor 1 (TEF1). We also present the new primer pair Fa+7/Ra+6. Mock Fusarium communities reflecting phylogenetic diversity were used to evaluate the accuracy of the primers in reflecting the relative abundance of the species. TEF1 amplicons were subjected to 454 high-throughput sequencing to characterize Fusarium communities. Field samples from soil and wheat kernels were included to test the method on more-complex material. For kernel samples, a single PCR was sufficient, while for soil samples, nested PCR was necessary. The newly developed primer pairs Fa+7/Ra+6 and Fa/Ra accurately reflected Fusarium species composition in mock DNA communities. In field samples, 47 Fusarium operational taxonomic units were identified, with the highest Fusarium diversity in soil. The Fusarium community in soil was dominated by members of the Fusarium incarnatum-Fusarium equiseti species complex, contradicting findings in previous studies. The method was successfully applied to analyze Fusarium communities in soil and plant material and can facilitate further studies of Fusarium ecology.

  6. Genus-Specific Primers for Study of Fusarium Communities in Field Samples

    PubMed Central

    Edel-Hermann, Véronique; Gautheron, Nadine; Durling, Mikael Brandström; Kolseth, Anna-Karin; Steinberg, Christian; Persson, Paula; Friberg, Hanna

    2015-01-01

    Fusarium is a large and diverse genus of fungi of great agricultural and economic importance, containing many plant pathogens and mycotoxin producers. To date, high-throughput sequencing of Fusarium communities has been limited by the lack of genus-specific primers targeting regions with high discriminatory power at the species level. In the present study, we evaluated two Fusarium-specific primer pairs targeting translation elongation factor 1 (TEF1). We also present the new primer pair Fa+7/Ra+6. Mock Fusarium communities reflecting phylogenetic diversity were used to evaluate the accuracy of the primers in reflecting the relative abundance of the species. TEF1 amplicons were subjected to 454 high-throughput sequencing to characterize Fusarium communities. Field samples from soil and wheat kernels were included to test the method on more-complex material. For kernel samples, a single PCR was sufficient, while for soil samples, nested PCR was necessary. The newly developed primer pairs Fa+7/Ra+6 and Fa/Ra accurately reflected Fusarium species composition in mock DNA communities. In field samples, 47 Fusarium operational taxonomic units were identified, with the highest Fusarium diversity in soil. The Fusarium community in soil was dominated by members of the Fusarium incarnatum-Fusarium equiseti species complex, contradicting findings in previous studies. The method was successfully applied to analyze Fusarium communities in soil and plant material and can facilitate further studies of Fusarium ecology. PMID:26519387

  7. Antibacterial Activity of Cinnamaldehyde and Estragole Extracted from Plant Essential Oils against Pseudomonas syringae pv. actinidiae Causing Bacterial Canker Disease in Kiwifruit

    PubMed Central

    Song, Yu-Rim; Choi, Min-Seon; Choi, Geun-Won; Park, Il-Kwon; Oh, Chang-Sik

    2016-01-01

    Pseudomonas syringae pv. actinidiae (Psa) causes bacterial canker disease in kiwifruit. Antibacterial activity of plant essential oils (PEOs) originating from 49 plant species were tested against Psa by a vapor diffusion and a liquid culture assays. The five PEOs from Pimenta racemosa, P. dioica, Melaleuca linariifolia, M. cajuputii, and Cinnamomum cassia efficiently inhibited Psa growth by either assays. Among their major components, estragole, eugenol, and methyl eugenol showed significant antibacterial activity by only the liquid culture assay, while cinnamaldehyde exhibited antibacterial activity by both assays. The minimum inhibitory concentrations (MICs) of estragole and cinnamaldehyde by the liquid culture assay were 1,250 and 2,500 ppm, respectively. The MIC of cinnamaldehyde by the vapor diffusion assay was 5,000 ppm. Based on the formation of clear zones or the decrease of optical density caused by these compounds, they might kill the bacterial cells and this feature might be useful for managing the bacterial canker disease in kiwifruit. PMID:27493612

  8. Effects of the deletion and over-expression of Fusarium graminearum gene FgHal2 on host response to mycovirus Fusarium graminearum virus 1.

    PubMed

    Yu, Jisuk; Lee, Kyung-Mi; Son, Moonil; Kim, Kook-Hyung

    2015-09-01

    The mycovirus Fusarium graminearum virus 1 (FgV1) is associated with reduced virulence (hypovirulence) of Fusarium graminearum. Transcriptomic and proteomic expression profiling have shown that many F. graminearum genes are differentially expressed as a consequence of FgV1 infection. Several of these genes may be related to the maintenance of the virus life cycle. The host gene, FgHal2, which has a highly conserved 3'-phosphoadenosine 5'-phosphatase (PAP phosphatase-like) domain or inositol monophosphatase (IMPase) superfamily domain, shows reduced expression in response to FgV1 infection. We generated targeted gene deletion and over-expression mutants to clarify the possible function(s) of FgHal2 and its relationship to FgV1. The gene deletion mutant showed retarded growth, reduced aerial mycelia formation and reduced pigmentation, whereas over-expression mutants were morphologically similar to the wild-type (WT). Furthermore, compared with the WT, the gene deletion mutant produced fewer conidia and these showed abnormal morphology. The FgHal2 expression level was decreased by FgV1 infection at 120 h post-inoculation (hpi), whereas the levels were nine-fold greater for both the virus-free and virus-infected over-expression mutant than for the WT. FgV1 RNA accumulation was decreased in the deletion mutant at 48, 72 and 120 hpi. FgV1 RNA accumulation in the over-expression mutant was reduced relative to that of the WT at 48 and 120 hpi, but was similar to that of the WT at 72 hpi. The vertical transmission rate of FgV1 in the gene deletion mutant was low, suggesting that FgHal2 may be required for the maintenance of FgV1 in the host cell. Together, these results indicate that the putative 3'(2'),5'-bisphosphate nucleotidase gene, FgHal2, has diverse biological functions in the host fungus and may affect the viral RNA accumulation and transmission of FgV1.

  9. Methyl Salicylate Level Increase in Flax after Fusarium oxysporum Infection Is Associated with Phenylpropanoid Pathway Activation

    PubMed Central

    Boba, Aleksandra; Kostyn, Kamil; Kostyn, Anna; Wojtasik, Wioleta; Dziadas, Mariusz; Preisner, Marta; Szopa, Jan; Kulma, Anna

    2017-01-01

    Flax (Linum usitatissimum) is a crop plant valued for its oil and fiber. Unfortunately, large losses in cultivation of this plant are caused by fungal infections, with Fusarium oxysporum being one of its most dangerous pathogens. Among the plant's defense strategies, changes in the expression of genes of the shikimate/phenylpropanoid/benzoate pathway and thus in phenolic contents occur. Among the benzoates, salicylic acid, and its methylated form methyl salicylate play an important role in regulating plants' response to stress conditions. Upon treatment of flax plants with the fungus we found that methyl salicylate content increased (4.8-fold of the control) and the expression profiles of the analyzed genes suggest that it is produced most likely from cinnamic acid, through the β-oxidative route. At the same time activation of some genes involved in lignin and flavonoid biosynthesis was observed. We suggest that increased methyl salicylate biosynthesis during flax response to F. oxysporum infection may be associated with phenylpropanoid pathway activation. PMID:28163709

  10. Real-time imaging of hydrogen peroxide dynamics in vegetative and pathogenic hyphae of Fusarium graminearum

    PubMed Central

    Mentges, Michael; Bormann, Jörg

    2015-01-01

    Balanced dynamics of reactive oxygen species in the phytopathogenic fungus Fusarium graminearum play key roles for development and infection. To monitor those dynamics, ratiometric analysis using the novel hydrogen peroxide (H2O2) sensitive fluorescent indicator protein HyPer-2 was established for the first time in phytopathogenic fungi. H2O2 changes the excitation spectrum of HyPer-2 with an excitation maximum at 405 nm for the reduced and 488 nm for the oxidized state, facilitating ratiometric readouts with maximum emission at 516 nm. HyPer-2 analyses were performed using a microtiter fluorometer and confocal laser scanning microscopy (CLSM). Addition of external H2O2 to mycelia caused a steep and transient increase in fluorescence excited at 488 nm. This can be reversed by the addition of the reducing agent dithiothreitol. HyPer-2 in F. graminearum is highly sensitive and specific to H2O2 even in tiny amounts. Hyperosmotic treatment elicited a transient internal H2O2 burst. Hence, HyPer-2 is suitable to monitor the intracellular redox balance. Using CLSM, developmental processes like nuclear division, tip growth, septation, and infection structure development were analyzed. The latter two processes imply marked accumulations of intracellular H2O2. Taken together, HyPer-2 is a valuable and reliable tool for the analysis of environmental conditions, cellular development, and pathogenicity. PMID:26446493

  11. Fusarium Oxysporum Volatiles Enhance Plant Growth Via Affecting Auxin Transport and Signaling.

    PubMed

    Bitas, Vasileios; McCartney, Nathaniel; Li, Ningxiao; Demers, Jill; Kim, Jung-Eun; Kim, Hye-Seon; Brown, Kathleen M; Kang, Seogchan

    2015-01-01

    Volatile organic compounds (VOCs) have well-documented roles in plant-plant communication and directing animal behavior. In this study, we examine the less understood roles of VOCs in plant-fungal relationships. Phylogenetically and ecologically diverse strains of Fusarium oxysporum, a fungal species complex that often resides in the rhizosphere of assorted plants, produce volatile compounds that augment shoot and root growth of Arabidopsis thaliana and tobacco. Growth responses of A. thaliana hormone signaling mutants and expression patterns of a GUS reporter gene under the auxin-responsive DR5 promoter supported the involvement of auxin signaling in F. oxysporum volatile-mediated growth enhancement. In addition, 1-naphthylthalamic acid, an inhibitor of auxin efflux, negated F. oxysporum volatile-mediated growth enhancement in both plants. Comparison of the profiles of volatile compounds produced by F. oxysporum strains that differentially affected plant growth suggests that the relative compositions of both growth inhibitory and stimulatory compounds may determine the degree of plant growth enhancement. Volatile-mediated signaling between fungi and plants may represent a potentially conserved, yet mostly overlooked, mechanism underpinning plant-fungus interactions and fungal niche adaption.

  12. Transcriptome-Based Discovery of Fusarium graminearum Stress Responses to FgHV1 Infection

    PubMed Central

    Wang, Shuangchao; Zhang, Jingze; Li, Pengfei; Qiu, Dewen; Guo, Lihua

    2016-01-01

    Fusarium graminearum hypovirus 1 (FgHV1), which is phylogenetically related to Cryphonectria hypovirus 1 (CHV1), is a virus in the family Hypoviridae that infects the plant pathogenic fungus F. graminearum. Although hypovirus FgHV1 infection does not attenuate the virulence of the host (hypovirulence), it results in defects in mycelial growth and spore production. We now report that the vertical transmission rate of FgHV1 through asexual spores reached 100%. Using RNA deep sequencing, we performed genome-wide expression analysis to reveal phenotype-related genes with expression changes in response to FgHV1 infection. A total of 378 genes were differentially expressed, suggesting that hypovirus infection causes a significant alteration of fungal gene expression. Nearly two times as many genes were up-regulated as were down-regulated. A differentially expressed gene enrichment analysis identified a number of important pathways. Metabolic processes, the ubiquitination system, and especially cellular redox regulation were the most affected categories in F. graminearum challenged with FgHV1. The p20, encoded by FgHV1 could induce H2O2 accumulation and hypersensitive response in Nicotiana benthamiana leaves. Moreover, hypovirus FgHV1 may regulate transcription factors and trigger the RNA silencing pathway in F. graminearum. PMID:27869679

  13. Transcriptome-Based Discovery of Fusarium graminearum Stress Responses to FgHV1 Infection.

    PubMed

    Wang, Shuangchao; Zhang, Jingze; Li, Pengfei; Qiu, Dewen; Guo, Lihua

    2016-11-17

    Fusarium graminearum hypovirus 1 (FgHV1), which is phylogenetically related to Cryphonectria hypovirus 1 (CHV1), is a virus in the family Hypoviridae that infects the plant pathogenic fungus F. graminearum. Although hypovirus FgHV1 infection does not attenuate the virulence of the host (hypovirulence), it results in defects in mycelial growth and spore production. We now report that the vertical transmission rate of FgHV1 through asexual spores reached 100%. Using RNA deep sequencing, we performed genome-wide expression analysis to reveal phenotype-related genes with expression changes in response to FgHV1 infection. A total of 378 genes were differentially expressed, suggesting that hypovirus infection causes a significant alteration of fungal gene expression. Nearly two times as many genes were up-regulated as were down-regulated. A differentially expressed gene enrichment analysis identified a number of important pathways. Metabolic processes, the ubiquitination system, and especially cellular redox regulation were the most affected categories in F. graminearum challenged with FgHV1. The p20, encoded by FgHV1 could induce H₂O₂ accumulation and hypersensitive response in Nicotiana benthamiana leaves. Moreover, hypovirus FgHV1 may regulate transcription factors and trigger the RNA silencing pathway in F. graminearum.

  14. Transcription factor RFX1 is crucial for maintenance of genome integrity in Fusarium graminearum.

    PubMed

    Min, Kyunghun; Son, Hokyoung; Lim, Jae Yun; Choi, Gyung Ja; Kim, Jin-Cheol; Harris, Steven D; Lee, Yin-Won

    2014-03-01

    The survival of cellular organisms depends on the faithful replication and transmission of DNA. Regulatory factor X (RFX) transcription factors are well conserved in animals and fungi, but their functions are diverse, ranging from the DNA damage response to ciliary gene regulation. We investigated the role of the sole RFX transcription factor, RFX1, in the plant-pathogenic fungus Fusarium graminearum. Deletion of rfx1 resulted in multiple defects in hyphal growth, conidiation, virulence, and sexual development. Deletion mutants of rfx1 were more sensitive to various types of DNA damage than the wild-type strain. Septum formation was inhibited and micronuclei were produced in the rfx1 deletion mutants. The results of the neutral comet assay demonstrated that disruption of rfx1 function caused spontaneous DNA double-strand breaks (DSBs). The transcript levels of genes involved in DNA DSB repair were upregulated in the rfx1 deletion mutants. DNA DSBs produced micronuclei and delayed septum formation in F. graminearum. Green fluorescent protein (GFP)-tagged RFX1 localized in nuclei and exhibited high expression levels in growing hyphae and conidiophores, where nuclear division was actively occurring. RNA-sequencing-based transcriptomic analysis revealed that RFX1 suppressed the expression of many genes, including those required for the repair of DNA damage. Taken together, these findings indicate that the transcriptional repressor rfx1 performs crucial roles during normal cell growth by maintaining genome integrity.

  15. Purification and characterization of 4-N-trimethylamino-1-butanol dehydrogenase from Fusarium merismoides var. acetilereum.

    PubMed

    Fujimitsu, Hiroshi; Taniyama, Yuko; Tajima, Sae; Mohamed Ahmed, Isam A; Arima, Jiro; Mori, Nobuhiro

    2016-09-01

    From investigation of 60 filamentous fungi, we identified Fusarium merismoides var. acetilereum, which uses 4-N-trimethylamino-1-butanol (TMA-butanol) as the sole source of carbon and nitrogen. The fungus produced NAD(+)-dependent TMA-butanol dehydrogenase (DH) when it was cultivated in medium containing TMA-butanol. The enzyme showed molecular mass of 40 kDa by SDS-PAGE and 160 kDa by gel filtration, suggesting that it is a homotetramer. TMA-butanol DH is stable at pH 7.5-9.0. It exhibits moderate stability with respect to temperature (up to 30 °C). Additionally, it has optimum activity at 45 °C and at pH 9.5. The enzyme has broad specificity to various alkyl alcohols and amino alkyl alcohols, and the carbon chains of which are longer than butanol. Moreover, the activity is strongly inhibited by oxidizing agents, carbonyl and thiol modulators, and chelating agents. This report is the first study examining TMA-butanol DH from eukaryotic microbes.

  16. Microbiological Aspects in the Hydroxylation of Estrogens by Fusarium moniliforme1

    PubMed Central

    Casas-Campillo, C.; Bautista, M.

    1965-01-01

    A strain of Fusarium moniliforme (IH4), isolated from soil, showed outstanding enzymatic abilities to hydroxylate a number of estrogens. Estrone and estradiol were transformed into the 15α-hydroxy derivatives, and estradiol 3-methyl ether was transformed into the corresponding 6β-hydroxy derivative. Δ6-Estrone was not hydroxylated. The accumulation of 15α-hydroxyestrone was influenced by the nutritional conditions of the fungus. Maximal yield was obtained when the organism grew in Czapek solution supplemented with yeast extract, although good conversion was also found in a peptone-corn molasses medium. Substitution of NO3-N in Czapek medium with NH4-N, lactalbumin hydrolysate, Casitone, or Casamino Acids resulted in limited hydroxylation of estrone. A remarkable strain specificity was demonstrated in this conversion. Of 13 strains of F. moniliforme and Gibberella fujikuroi under investigation, only 2 strains (IH4 and ATCC 9851) accumulated substantial amounts of the 15α-hydroxylated product. However, marked quantitative variations were observed which are attributable to a different ability of the organisms to degrade the steroid nucleus. Biochemical instabilities were also found through the appearance of spontaneous variants lacking steroid-hydroxylating activity. Replacement culture studies revealed that 15α-hydroxylation of estrone was dependent on the supply of external phosphate; exogenous nitrogen or energy sources were not required. Most of the enzymatic activity was confined to the mycelia. Microconidia showed a very limited hydroxylating activity, even in the presence of supplements or energy sources. Images Fig. 2 PMID:5866044

  17. Identification and synthesis of three cyclodidepsipeptides as potential precursors of enniatin B in Fusarium sporotrichioides

    NASA Astrophysics Data System (ADS)

    Smelcerovic, Andrija; Yancheva, Denitsa; Cherneva, Emiliya; Petronijevic, Zivomir; Lamshoeft, Marc; Herebian, Diran

    2011-01-01

    A pathogenic fungus, Fusarium sporotrichioides Sherb., was isolated from Hypericum barbatum Jacq. The volatile compounds of broth and mycelium were analyzed using GC-MS and three cyclodidepsipeptides (dioxomorpholines), 3,6-di(propan-2-yl)-4-methyl-morpholine-2,5-dione, 3-(2-methylpropyl)-6-(propan-2-yl)-4-methyl-morpholine-2,5-dione and 3-(butan-2-yl)-6-(propan-2-yl)-4-methyl-morpholine-2,5-dione, were found for the first time in the natural products. The structures of the compounds were confirmed by comparison of the analytical data for the natural products with samples obtained via synthetic methods. The conformational features and vibrational spectra of the three cyclodidepsipeptides were characterized by density functional theory (DFT) calculations and IR spectroscopy. The cyclic hexadepsipeptide enniatin B was identified by a LC-MS/MS analysis of the non-volatile products of broth and mycelium. The above-mentioned three cyclodidepsipeptides are probably synthesized using similar biosynthetic ways to enniatin B involving a nonribosomal mechanism.

  18. Molecular Keys to the Janthinobacterium and Duganella spp. Interaction with the Plant Pathogen Fusarium graminearum.

    PubMed

    Haack, Frederike S; Poehlein, Anja; Kröger, Cathrin; Voigt, Christian A; Piepenbring, Meike; Bode, Helge B; Daniel, Rolf; Schäfer, Wilhelm; Streit, Wolfgang R

    2016-01-01

    Janthinobacterium and Duganella are well-known for their antifungal effects. Surprisingly, almost nothing is known on molecular aspects involved in the close bacterium-fungus interaction. To better understand this interaction, we established the genomes of 11 Janthinobacterium and Duganella isolates in combination with phylogenetic and functional analyses of all publicly available genomes. Thereby, we identified a core and pan genome of 1058 and 23,628 genes. All strains encoded secondary metabolite gene clusters and chitinases, both possibly involved in fungal growth suppression. All but one strain carried a single gene cluster involved in the biosynthesis of alpha-hydroxyketone-like autoinducer molecules, designated JAI-1. Genome-wide RNA-seq studies employing the background of two isolates and the corresponding JAI-1 deficient strains identified a set of 45 QS-regulated genes in both isolates. Most regulated genes are characterized by a conserved sequence motif within the promoter region. Among the most strongly regulated genes were secondary metabolite and type VI secretion system gene clusters. Most intriguing, co-incubation studies of J. sp. HH102 or its corresponding JAI-1 synthase deletion mutant with the plant pathogen Fusarium graminearum provided first evidence of a QS-dependent interaction with this pathogen.

  19. Fusarium verticillioides and fumonisin contamination in Bt and non-Bt maize cultivated in Brazil.

    PubMed

    Barroso, Vinícius M; Rocha, Liliana O; Reis, Tatiana A; Reis, Gabriela M; Duarte, Aildson P; Michelotto, Marcos D; Correa, Benedito

    2017-03-06

    Fusarium verticillioides is one of the main pathogens of maize, causing ear and stalk rots. This fungus is also able to produce high levels of fumonisins, which have been linked to various illnesses in humans and animals. Previous studies have shown that maize hybrids genetically modified with the cry genes from the bacterium Bacillus thuringiensis (Bt) presented lower incidence of F. verticillioides and fumonisin levels, presumably through the reduction of insects, which could act as vectors of fungi. The aim of this study was to assess the incidence of F. verticillioides and the concentration of fumonisins in Bt and isogenic non-Bt hybrids (2B710Hx, 30F35YG, 2B710, and 30F35, respectively). The samples of 2B710Hx and 30F35YG presented lower F. verticillioides frequency than 2B710 and 30F35 samples. However, there was no statistical difference between fumonisin contamination when Bt and non-Bt samples were compared (P > 0.05). The results suggest that other environmental parameters could possibly trigger fumonisin production during plant development in the field; consequently, other management strategies should be applied to aid controlling fumonisin contamination in maize.

  20. Fusarium Oxysporum Volatiles Enhance Plant Growth Via Affecting Auxin Transport and Signaling

    PubMed Central

    Bitas, Vasileios; McCartney, Nathaniel; Li, Ningxiao; Demers, Jill; Kim, Jung-Eun; Kim, Hye-Seon; Brown, Kathleen M.; Kang, Seogchan

    2015-01-01

    Volatile organic compounds (VOCs) have well-documented roles in plant-plant communication and directing animal behavior. In this study, we examine the less understood roles of VOCs in plant-fungal relationships. Phylogenetically and ecologically diverse strains of Fusarium oxysporum, a fungal species complex that often resides in the rhizosphere of assorted plants, produce volatile compounds that augment shoot and root growth of Arabidopsis thaliana and tobacco. Growth responses of A. thaliana hormone signaling mutants and expression patterns of a GUS reporter gene under the auxin-responsive DR5 promoter supported the involvement of auxin signaling in F. oxysporum volatile-mediated growth enhancement. In addition, 1-naphthylthalamic acid, an inhibitor of auxin efflux, negated F. oxysporum volatile-mediated growth enhancement in both plants. Comparison of the profiles of volatile compounds produced by F. oxysporum strains that differentially affected plant growth suggests that the relative compositions of both growth inhibitory and stimulatory compounds may determine the degree of plant growth enhancement. Volatile-mediated signaling between fungi and plants may represent a potentially conserved, yet mostly overlooked, mechanism underpinning plant-fungus interactions and fungal niche adaption. PMID:26617587

  1. The effector repertoire of Fusarium oxysporum determines the tomato xylem proteome composition following infection

    PubMed Central

    Gawehns, Fleur; Ma, Lisong; Bruning, Oskar; Houterman, Petra M.; Boeren, Sjef; Cornelissen, Ben J. C.; Rep, Martijn; Takken, Frank L. W.

    2015-01-01

    Plant pathogens secrete small proteins, of which some are effectors that promote infection. During colonization of the tomato xylem vessels the fungus Fusarium oxysporum f.sp. lycopersici (Fol) secretes small proteins that are referred to as SIX (Secreted In Xylem) proteins. Of these, Six1 (Avr3), Six3 (Avr2), Six5, and Six6 are required for full virulence, denoting them as effectors. To investigate their activities in the plant, the xylem sap proteome of plants inoculated with Fol wild-type or either AVR2, AVR3, SIX2, SIX5, or SIX6 knockout strains was analyzed with nano-Liquid Chromatography-Mass Spectrometry (nLC-MSMS). Compared to mock-inoculated sap 12 additional plant proteins appeared while 45 proteins were no longer detectable in the xylem sap of Fol-infected plants. Of the 285 proteins found in both uninfected and infected plants the abundance of 258 proteins changed significantly following infection. The xylem sap proteome of plants infected with four Fol effector knockout strains differed significantly from plants infected with wild-type Fol, while that of the SIX2-knockout inoculated plants remained unchanged. Besides an altered abundance of a core set of 24 differentially accumulated proteins (DAPs), each of the four effector knockout strains affected specifically the abundance of a subset of DAPs. Hence, Fol effectors have both unique and shared effects on the composition of the tomato xylem sap proteome. PMID:26583031

  2. Molecular Keys to the Janthinobacterium and Duganella spp. Interaction with the Plant Pathogen Fusarium graminearum

    PubMed Central

    Haack, Frederike S.; Poehlein, Anja; Kröger, Cathrin; Voigt, Christian A.; Piepenbring, Meike; Bode, Helge B.; Daniel, Rolf; Schäfer, Wilhelm; Streit, Wolfgang R.

    2016-01-01

    Janthinobacterium and Duganella are well-known for their antifungal effects. Surprisingly, almost nothing is known on molecular aspects involved in the close bacterium-fungus interaction. To better understand this interaction, we established the genomes of 11 Janthinobacterium and Duganella isolates in combination with phylogenetic and functional analyses of all publicly available genomes. Thereby, we identified a core and pan genome of 1058 and 23,628 genes. All strains encoded secondary metabolite gene clusters and chitinases, both possibly involved in fungal growth suppression. All but one strain carried a single gene cluster involved in the biosynthesis of alpha-hydroxyketone-like autoinducer molecules, designated JAI-1. Genome-wide RNA-seq studies employing the background of two isolates and the corresponding JAI-1 deficient strains identified a set of 45 QS-regulated genes in both isolates. Most regulated genes are characterized by a conserved sequence motif within the promoter region. Among the most strongly regulated genes were secondary metabolite and type VI secretion system gene clusters. Most intriguing, co-incubation studies of J. sp. HH102 or its corresponding JAI-1 synthase deletion mutant with the plant pathogen Fusarium graminearum provided first evidence of a QS-dependent interaction with this pathogen. PMID:27833590

  3. Transcriptional analysis of the sweet orange interaction with the citrus canker pathogens Xanthomonas axonopodis pv. citri and Xanthomonas axonopodis pv. aurantifolii.

    PubMed

    Cernadas, Raúl Andrés; Camillo, Luciana Rodrigues; Benedetti, Celso Eduardo

    2008-09-01

    Xanthomonas axonopodis pv. citri (Xac) and Xanthomonas axonopodis pv. aurantifolii pathotype C (Xaa) are responsible for citrus canker disease; however, while Xac causes canker on all citrus varieties, Xaa is restricted to Mexican lime, and in sweet oranges it triggers a defence response. To gain insights into the differential pathogenicity exhibited by Xac and Xaa and to survey the early molecular events leading to canker development, a detailed transcriptional analysis of sweet orange plants infected with the pathogens was performed. Using differential display, suppressed subtractive hybridization and microarrays, we identified changes in transcript levels in approximately 2.0% of the approximately 32,000 citrus genes examined. Genes with altered expression in response to Xac/Xaa surveyed at 6 and 48 h post-infection (hpi) were associated with cell-wall modifications, cell division and expansion, vesicle trafficking, disease resistance, carbon and nitrogen metabolism, and responses to hormones auxin, gibberellin and ethylene. Most of the genes that were commonly modulated by Xac and Xaa were associated with basal defences triggered by pathogen-associated molecular patterns, including those involved in reactive oxygen species production and lignification. Significantly, we detected clear changes in the transcriptional profiles of defence, cell-wall, vesicle trafficking and cell growth-related genes in Xac-infected leaves between 6 and 48 hpi. This is consistent with the notion that Xac suppresses host defences early during infection and simultaneously changes the physiological status of the host cells, reprogramming them for division and growth. Notably, brefeldin A, an inhibitor of vesicle trafficking, retarded canker development. In contrast, Xaa triggered a mitogen-activated protein kinase signalling pathway involving WRKY and ethylene-responsive transcriptional factors known to activate downstream defence genes.

  4. Fungus-insect gall of Phlebopus portentosus.

    PubMed

    Zhang, Chun-Xia; He, Ming-Xia; Cao, Yang; Liu, Jing; Gao, Feng; Wang, Wen-Bing; Ji, Kai-Ping; Shao, Shi-Cheng; Wang, Yun

    2015-01-01

    Phlebopus portentosus is a popular edible wild mushroom found in the tropical Yunnan, China, and northern Thailand. In its natural habitats, a gall often has been found on some plant roots, around which fungal fruiting bodies are produced. The galls are different from common insect galls in that their cavity walls are not made from plant tissue but rather from the hyphae of P. portentosus. Therefore we have termed this phenomenon "fungus-insect gall". Thus far six root mealy bug species in the family Pseudococcidae that form fungus-insect galls with P. portentosus have been identified: Formicococcus polysperes, Geococcus satellitum, Planococcus minor, Pseudococcus cryptus, Paraputo banzigeri and Rastrococcus invadens. Fungus-insect galls were found on the roots of more than 21 plant species, including Delonix regia, Citrus maxima, Coffea arabica and Artocarpus heterophyllus. Greenhouse inoculation trials showed that fungus-insect galls were found on the roots of A. heterophyllus 1 mo after inoculation. The galls were subglobose to globose, fulvous when young and became dark brown at maturation. Each gall harbored one or more mealy bugs and had a chimney-like vent for ventilation and access to the gall. The cavity wall had three layers. Various shaped mealy bug wax deposits were found inside the wall. Fungal hyphae invaded the epidermis of plant roots and sometimes even the cortical cells during the late stage of gall development. The identity of the fungus inside the cavity was confirmed by molecular methods.

  5. D-PSA-K: A Model for Estimating the Accumulated Potential Damage on Kiwifruit Canes Caused by Bacterial Canker during the Growing and Overwintering Seasons

    PubMed Central

    Do, Ki Seok; Chung, Bong Nam; Joa, Jae Ho

    2016-01-01

    We developed a model, termed D-PSA-K, to estimate the accumulated potential damage on kiwifruit canes caused by bacterial canker during the growing and overwintering seasons. The model consisted of three parts including estimation of the amount of necrotic lesion in a non-frozen environment, the rate of necrosis increase in a freezing environment during the overwintering season, and the amount of necrotic lesion on kiwifruit canes caused by bacterial canker during the overwintering and growing seasons. We evaluated the model’s accuracy by comparing the observed maximum disease incidence on kiwifruit canes against the damage estimated using weather and disease data collected at Wando during 1994–1997 and at Seogwipo during 2014–2015. For the Hayward cultivar, D-PSA-K estimated the accumulated damage as approximately nine times the observed maximum disease incidence. For the Hort16A cultivar, the accumulated damage estimated by D-PSA-K was high when the observed disease incidence was high. D-PSA-K could assist kiwifruit growers in selecting optimal sites for kiwifruit cultivation and establishing improved production plans by predicting the loss in kiwifruit production due to bacterial canker, using past weather or future climate change data. PMID:27904460

  6. D-PSA-K: A Model for Estimating the Accumulated Potential Damage on Kiwifruit Canes Caused by Bacterial Canker during the Growing and Overwintering Seasons.

    PubMed

    Do, Ki Seok; Chung, Bong Nam; Joa, Jae Ho

    2016-12-01

    We developed a model, termed D-PSA-K, to estimate the accumulated potential damage on kiwifruit canes caused by bacterial canker during the growing and overwintering seasons. The model consisted of three parts including estimation of the amount of necrotic lesion in a non-frozen environment, the rate of necrosis increase in a freezing environment during the overwintering season, and the amount of necrotic lesion on kiwifruit canes caused by bacterial canker during the overwintering and growing seasons. We evaluated the model's accuracy by comparing the observed maximum disease incidence on kiwifruit canes against the damage estimated using weather and disease data collected at Wando during 1994-1997 and at Seogwipo during 2014-2015. For the Hayward cultivar, D-PSA-K estimated the accumulated damage as approximately nine times the observed maximum disease incidence. For the Hort16A cultivar, the accumulated damage estimated by D-PSA-K was high when the observed disease incidence was high. D-PSA-K could assist kiwifruit growers in selecting optimal sites for kiwifruit cultivation and establishing improved production plans by predicting the loss in kiwifruit production due to bacterial canker, using past weather or future climate change data.

  7. Botryosphaeriaceae species associated with dieback and canker disease of bay laurel in northern California with the description of Dothiorella californica sp. nov.

    PubMed

    Lawrence, Daniel P; Peduto Hand, Francesca; Gubler, W Douglas; Trouillas, Florent P

    2017-04-01

    Members of the Botryosphaeriaceae are cosmopolitan fungi that may exist as seemingly innocuous endophytes or as destructive pathogens of numerous woody hosts, including fruit and nut crops, urban ornamental trees and shrubs, and forest trees. Surveys of bay laurel in northern California have revealed symptoms of dieback and branch canker of unknown aetiology. The goals of this study were to identify and clarify the species of Botryosphaeriaceae associated with these symptoms and to confirm their pathogenicity. To understand the role of members of the Botryosphaeriaceae in the dieback and canker disease of bay laurel, 23 isolates were isolated from symptomatic wood. Phylogenetic analyses of ITS, translation elongation factor 1-α, and beta-tubulin revealed three species: Botryosphaeria dothidea, Neofusicoccum nonquaesitum, and the newly described and typified species Dothiorella californica sp. nov. When select isolates were inoculated to 2- to 3-year-old branches of Umbellularia californica in a natural forest, both B. dothidea and N. nonquaesitum were pathogenic with N. nonquaesitum producing the largest lesions at 12- and 18-months post inoculation, respectively, while Do. californica did not cause wood lesions significantly greater than the mock-inoculated controls. This study represents the first attempt to identify and test the pathogenicity of Botryosphaeriaceae species associated with dieback and canker disease of bay laurel in a northern California forest.

  8. INOCULATION METHODS TO ASSAY WHEAT SEEDLINGS FOR RESISTANCE TO FUSARIUM CROWN ROT IN A CONTROLLED ENVIRONMENT

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Adequate Fusarium screening systems must be established to appropriately phenotype mapping populations for accurate QTL identification. The objective of this research was to find an inoculation method with the greatest consistency and least variation for identifying QTL. Two Fusarium pseudograminear...

  9. Near-infrared versus visual sorting of Fusarium-damaged kernels in winter wheat

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Fusarium head blight of wheat, caused by Fusarium graminearum, often results in shriveled and/or discolored kernels referred to as Fusarium-damaged kernels (FDK). FDK is one of the major grain grading factors and therefore is routinely determined for purposes of quality assurance. Determination o...

  10. Comparative genomics of the Fusarium fujikuroi species complex: biosynthetic pathways metabolite production and plant pathogenicity

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Fusarium is a huge genus of filamentous fungi causing plant diseases in a wide range of host plants that result in high economic losses to world agriculture every year. Phylogenetic studies have shown that the genus Fusarium consists of different species complexes. One of them is the “Fusarium fujik...

  11. Wildly Growing Asparagus (Asparagus officinalis L.) Hosts Pathogenic Fusarium Species and Accumulates Their Mycotoxins.

    PubMed

    Stępień, Łukasz; Waśkiewicz, Agnieszka; Urbaniak, Monika

    2016-05-01

    Asparagus officinalis L. is an important crop in many European countries, likely infected by a number of Fusarium species. Most of them produce mycotoxins in plant tissues, thus affecting the physiology of the host plant. However, there is lack of information on Fusarium communities in wild asparagus, where they would definitely have considerable environmental significance. Therefore, the main scientific aim of this study was to identify the Fusarium species and quantify their typical mycotoxins present in wild asparagus plants collected at four time points of the season. Forty-four Fusarium strains of eight species--Fusarium acuminatum, Fusarium avenaceum, Fusarium culmorum, Fusarium equiseti, Fusarium oxysporum, Fusarium proliferatum, Fusarium sporotrichioides, and Fusarium tricinctum--were isolated from nine wild asparagus plants in 2013 season. It is the first report of F. sporotrichioides isolated from this particular host. Fumonisin B1 was the most abundant mycotoxin, and the highest concentrations of fumonisins B1-B3 and beauvericin were found in the spears collected in May. Moniliformin and enniatins were quantified at lower concentrations. Mycotoxins synthesized by individual strains obtained from infected asparagus tissues were assessed using in vitro cultures on sterile rice grain. Most of the F. sporotrichioides strains synthesized HT-2 toxin and F. equiseti strains were found to be effective zearalenone producers.

  12. First report of Fusarium redolens causing crown rot of wheat (Triticum spp.) in Turkey

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Fusarium crown rot, caused by a complex of Fusarium spp., is a yield-limiting disease of wheat world-wide, especially in dry Mediterranean climates. In order to identify Fusarium species associated with crown rot of wheat, a survey was conducted in summer 2013 in the major wheat growing regions of T...

  13. Fusarium Osteomyelitis in a Patient With Pearson Syndrome: Case Report and Review of the Literature

    PubMed Central

    Hiebert, Rachael M.; Welliver, Robert C.; Yu, Zhongxin

    2016-01-01

    Fusarium species are ubiquitous fungi causing a wide array of infections, including invasive disease in the immunosuppressed. We present a fusarium bone infection in a child with Pearson syndrome and review the literature. Ten cases of fusarium osteomyelitis were reported in the past 40 years, and we review the treatments. PMID:27757410

  14. Effect of soil biochar amendment on grain crop resistance to Fusarium mycotoxin contamination

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Mycotoxin contamination of food and feed is among the top food safety concerns. Fusarium spp. cause serious diseases in cereal crops reducing yield and contaminating grain with mycotoxins that can be deleterious to human and animal health. Fusarium graminearum and Fusarium verticillioides infect whe...

  15. Elite-upland cotton germplasm-pool assessment of Fusarium wilt resistance in California

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Host-plant resistance is currently the most economic and effective strategy for managing Fusarium wilt [Fusarium oxysporum f. sp. vasinfectum (FOV)] disease. Over the past nine years, a new race of Fusarium (FOV race 4) has increasingly impacted cotton (Gossypium spp.) in production fields in the Sa...

  16. Metabolites from Aspergillus fumigatus, an endophytic fungus associated with Melia azedarach, and their antifungal, antifeedant, and toxic activities.

    PubMed

    Li, Xiao-Jun; Zhang, Qiang; Zhang, An-Ling; Gao, Jin-Ming

    2012-04-04

    Thirty-nine fungal metabolites 1-39, including two new alkaloids, 12β-hydroxy-13α-methoxyverruculogen TR-2 (6) and 3-hydroxyfumiquinazoline A (16), were isolated from the fermentation broth of Aspergillus fumigatus LN-4, an endophytic fungus isolated from the stem bark of Melia azedarach. Their structures were elucidated on the basis of detailed spectroscopic analysis (mass spectrometry and one- and two-dimensional NMR experiments) and by comparison of their NMR data with those reported in the literature. These isolated compounds were evaluated for in vitro antifungal activities against some phytopathogenic fungi, toxicity against brine shrimps, and antifeedant activities against armyworm larvae (Mythimna separata Walker). Among them, sixteen compounds showed potent antifungal activities against phytopathogenic fungi (Botrytis cinerea, Alternaria solani, Alternaria alternata, Colletotrichum gloeosporioides, Fusarium solani, Fusarium oxysporum f. sp. niveum, Fusarium oxysporum f. sp. vasinfectum, and Gibberella saubinettii), and four of them, 12β-hydroxy-13α-methoxyverruculogen TR-2 (6), fumitremorgin B (7), verruculogen (8), and helvolic acid (39), exhibited antifungal activities with MIC values of 6.25-50 μg/mL, which were comparable to the two positive controls carbendazim and hymexazol. In addition, of eighteen that exerted moderate lethality toward brine shrimps, compounds 7 and 8 both showed significant toxicities with median lethal concentration (LC(50)) values of 13.6 and 15.8 μg/mL, respectively. Furthermore, among nine metabolites that were found to possess antifeedant activity against armyworm larvae, compounds 7 and 8 gave the best activity with antifeedant indexes (AFI) of 50.0% and 55.0%, respectively. Structure-activity relationships of the metabolites were also discussed.

  17. Dentigerumycin: a bacterial mediator of an ant-fungus symbiosis.

    PubMed

    Oh, Dong-Chan; Poulsen, Michael; Currie, Cameron R; Clardy, Jon

    2009-06-01

    Fungus-growing ants engage in mutualistic associations with both the fungus they cultivate for food and actinobacteria (Pseudonocardia spp.) that produce selective antibiotics to defend that fungus from specialized fungal parasites. We have analyzed one such system at the molecular level and found that the bacterium associated with the ant Apterostigma dentigerum produces dentigerumycin, a cyclic depsipeptide with highly modified amino acids, to selectively inhibit the associated parasitic fungus (Escovopsis sp.).

  18. Taxonomy, biology, and clinical aspects of Fusarium species.

    PubMed Central

    Nelson, P E; Dignani, M C; Anaissie, E J

    1994-01-01

    There are several taxonomic systems available for identifying Fusarium species. The philosophy used in each taxonomic system is discussed as well as problems encountered in working with Fusarium species in culture. Fusarium species are toxigenic, and the mycotoxins produced by these organisms are often associated with animal and human diseases. The implications for the association of the carcinogens, fumonisins, produced by Fusarium moniliforme and other Fusarium species with human diseases are discussed. Foreign-body-associated fusarial infection such as keratitis in contact lens wearers, onychomycosis, skin infections, and disseminated multiorgan infections are discussed. Disseminated fusarial hyalohyphomycosis has emerged as a significant, usually fatal infection in the immunocompromised host. Successful outcome is determined by the degree of immunosuppression, the extent of the infection, and the presence of a removable focus such as an indwelling central venous catheter. These infections may be clinically suspected on the basis of a constellation of clinical and laboratory findings, which should lead to prompt therapy, probably with one of the newer antifungal agents. Perhaps the use of such agents or the use of colony-stimulating factors may improve the outcome of this devastating infection. However, until new approaches for treatment develop, effective preventive measures are urgently needed. Images PMID:7834602

  19. Structural and Functional Characterization of the TRI101 Trichothecene 3-O-Acetyltransferase from Fusarium sporotrichioides and Fusarium graminearum: KINETIC INSIGHTS TO COMBATING FUSARIUM HEAD BLIGHT

    SciTech Connect

    Garvey, Graeme S.; McCormick, Susan P.; Rayment, Ivan

    2008-06-30

    Fusarium head blight (FHB) is a plant disease with serious economic and health impacts. It is caused by fungal species belonging to the genus Fusarium and the mycotoxins they produce. Although it has proved difficult to combat this disease, one strategy that has been examined is the introduction of an indigenous fungal protective gene into cereals such as wheat barley and rice. Thus far the gene of choice has been tri101 whose gene product catalyzes the transfer of an acetyl group from acetyl coenzyme A to the C3 hydroxyl moiety of several trichothecene mycotoxins. In vitro this has been shown to reduce the toxicity of the toxins by {approx}100-fold but has demonstrated limited resistance to FHB in transgenic cereal. To understand the molecular basis for the differences between in vitro and in vivo resistance the three-dimensional structures and kinetic properties of two TRI101 orthologs isolated from Fusarium sporotrichioides and Fusarium graminearum have been determined. The kinetic results reveal important differences in activity of these enzymes toward B-type trichothecenes such as deoxynivalenol. These differences in activity can be explained in part by the three-dimensional structures for the ternary complexes for both of these enzymes with coenzyme A and trichothecene mycotoxins. The structural and kinetic results together emphasize that the choice of an enzymatic resistance gene in transgenic crop protection strategies must take into account the kinetic profile of the selected protein.

  20. Photodynamic treatment with phenothiazinium photosensitizers kills both ungerminated and germinated microconidia of the pathogenic fungi Fusarium oxysporum, Fusarium moniliforme and Fusarium solani.

    PubMed

    de Menezes, Henrique Dantas; Tonani, Ludmilla; Bachmann, Luciano; Wainwright, Mark; Braga, Gilberto Úbida Leite; von Zeska Kress, Marcia Regina

    2016-11-01

    The search for alternatives to control microorganisms is necessary both in clinical and agricultural areas. Antimicrobial photodynamic treatment (APDT) is a promising light-based approach that can be used to control both human and plant pathogenic fungi. In the present study, we evaluated the effects of photodynamic treatment with red light and four phenothiazinium photosensitizers (PS): methylene blue (MB), toluidine blue O (TBO), new methylene blue N (NMBN) and the phenothiazinium derivative S137 on ungerminated and germinated microconidia of Fusarium oxysporum, F. moniliforme, and F. solani. APDT with each PS killed efficiently both the quiescent ungerminated microconidia and metabolically active germinated microconidia of the three Fusarium species. Washing away the unbound PS from the microconidia (both ungerminated and germinated) before red light exposure reduced but did not prevent the effect of APDT. Subcelullar localization of PS in ungerminated and germinated microconidia and the effects of photodynamic treatment on cell membranes were also evaluated in the three Fusarium species. APDT with MB, TBO, NMBN or S137 increased the membrane permeability in microconidia and APDT with NMBN or S137 increased the lipids peroxidation in microconidia of the three Fusarium species. These findings expand the understanding of photodynamic inactivation of filamentous fungi with phenothiazinium PS.

  1. Antagonistic Activities of Novel Peptides from Bacillus amyloliquefaciens PT14 against Fusarium solani and Fusarium oxysporum.

    PubMed

    Kim, Young Gwon; Kang, Hee Kyoung; Kwon, Kee-Deok; Seo, Chang Ho; Lee, Hyang Burm; Park, Yoonkyung

    2015-12-09

    Bacillus species have recently drawn attention due to their potential use in the biological control of fungal diseases. This paper reports on the antifungal activity of novel peptides isolated from Bacillus amyloliquefaciens PT14. Reverse-phase high-performance liquid chromatography revealed that B. amyloliquefaciens PT14 produces five peptides (PT14-1, -2, -3, -4a, and -4b) that exhibit antifungal activity but are inactive against bacterial strains. In particular, PT14-3 and PT14-4a showed broad-spectrum antifungal activity against Fusarium solani and Fusarium oxysporum. The PT14-4a N-terminal amino acid sequence was identified through Edman degradation, and a BLAST homology analysis showed it not to be identical to any other protein or peptide. PT14-4a displayed strong fungicidal activity with minimal inhibitory concentrations of 3.12 mg/L (F. solani) and 6.25 mg/L (F. oxysporum), inducing severe morphological deformation in the conidia and hyphae. On the other hand, PT14-4a had no detectable hemolytic activity. This suggests PT14-4a has the potential to serve as an antifungal agent in clinical therapeutic and crop-protection applications.

  2. Characterization of Fusarium secorum, a new species causing Fusarium yellowing decline of sugar beet in north central USA.

    PubMed

    Secor, Gary A; Rivera-Varas, Viviana; Christ, Daniela S; Mathew, Febina M; Khan, Mohamed F R; Varrelmann, Mark; Bolton, Melvin D

    2014-01-01

    This study characterized a novel sugar beet (Beta vulgaris L.) pathogen from the Red River Valley in north central USA, which was formally named Fusarium secorum. Molecular phylogenetic analyses of three loci (translation elongation factor1α, calmodulin, mitochondrial small subunit) and phenotypic data strongly supported the inclusion of F. secorum in the Fusarium fujikuroi species complex (FFSC). Phylogenetic analyses identified F. secorum as a sister taxon of F. acutatum and a member of the African subclade of the FFSC. Fusarium secorum produced circinate hyphae sometimes bearing microconidia and abundant corkscrew-shaped hyphae in culture. To assess mycotoxin production potential, 45 typical secondary metabolites were tested in F. secorum rice cultures, but only beauvericin was produced in detectable amounts by each isolate. Results of pathogenicity experiments revealed that F. secorum isolates are able to induce half- and full-leaf yellowing foliar symptoms and vascular necrosis in roots and petioles of sugar beet. Inoculation with F. acutatum did not result in any disease symptoms. The sugar beet disease caused by F. secorum is named Fusarium yellowing decline. Since Fusarium yellowing decline incidence has been increasing in the Red River Valley, disease management options are discussed.

  3. [Tinea pedis due to Fusarium solani in Dakar].

    PubMed

    Diongue, K; Ndiaye, M; Badiane, A S; Seck, M C; Ndoye, N W; Diallo, S; Diallo, M A; Ndir, O; Ndiaye, D

    2015-06-01

    A patient presented with intertrigo at the second, third and fourth interdigitals spaces lasting for four years in which Fusarium solani was highlighted. The search for contributing factors revealed a concept of foot washing with water at least five times a day for ablutions, associated with wearing closed shoes all day and the absence of immunosuppression and diabetes. The diagnosis of Fusarium was made on the basis of direct examination and culture. Combined treatment with griseofulvin oral and topical ciclopirox was introduced and allowed healing after 45 days at which an antifungal powder was prescribed for relay. This case adds to the rare cases of intertrigo Fusarium sp. and confirms the frequent practice of ablutions as favoring factor.

  4. Comparative ultrastructure of nonwounded Mexican lime and Yuzu leaves infected with the citrus canker bacterium Xanthomonas citri pv. citri.

    PubMed

    Lee, In Jung; Kim, Ki Woo; Hyun, Jae Wook; Lee, Yong Hoon; Park, Eun Woo

    2009-07-01

    Ultrastructural aspects of citrus canker development were investigated in nonwounded leaves of citrus species by transmission electron microscopy (TEM). A susceptible species Mexican lime and a resistant species Yuzu were spray-inoculated with a virulent strain of Xanthomonas citri pv. citri. Initial symptoms occurred on Mexican lime approximately 9 days after inoculation, whereas they appeared on Yuzu mostly 11 days after inoculation. In Mexican lime leaves, the bacterial invasion was usually accompanied by host cell wall dissolution and cellular disruption. Fibrillar materials from degenerated cell walls were usually found in intercellular spaces. Damaged host cells with necrotic cytoplasm showed the localized separation of plasma membrane from the cell wall. Bacterial multiplication and electron-transparent capsule-like structures around bacteria were commonly observed. Meanwhile, cell wall protuberances were prominent outside host cell walls in response to bacterial invasion in Yuzu leaves. Occlusion of intercellular spaces was also formed by the fusion of two or more individual cell wall protuberances originated from two adjacent host cells. Papillae-like materials accumulated locally within host cells in close proximity to bacteria. Some bacteria were found to be undergoing degeneration in xylem vessels. Also, the shrunken, inactive bacteria were surrounded by electron-translucent fibrillar materials in intercellular spaces, implying bacterial immobilization. These cellular responses are thought to be the consequences of defense responses of Yuzu leaves to invading bacteria. In both citrus species, X. citri pv. citri contained polyphosphate bodies showing electron-dense and elliptical structures in cytoplasm.

  5. Genetic Diversity and Pathogenicity of Xanthomonas axonopodis Strains Inducing Citrus Canker Disease in Iran and South Korea.

    PubMed

    Khodakaramian, G; Swings, J

    2011-06-01

    For the first time in 1989 citrus bacterial canker disease has seen on Citrusaurantiifolia in southern Iran. A total of 43 strains from affected citrus trees, ten strains from South Korea and representative from all known five pathotypes of Xanthomonas axonopodis pathogenic on citrus trees were used in this study. Isolated strains from Iran were indistinguishable by phenotypic, FAMEs, and SDS-PAGE analyses but showed different host range. First group were pathogenic on all tested citrus seedlings including C. aurantiifolia, C. limettioides, C. limon, C. jambhiri, Poncirus trifoliata X C. paradisi, C. aurantium, C. paradise, C. medica, P. trifoliate, C. grandis, C. sinensis, C. reticulate and C. sinensis X P. trifoliate. Pathogenicity of the second group were limited to C. aurantiifolia, C. limettioides, C. limon, C. jambhiri, P. trifoliata X C. paradis, and C. aurantium. Among the strains studied by AFLP fingerprinting six clusters were found. These clusters were: (1) strains of pathotype C; (2) strains of pathotypes B and D; (3) strains of pathotype A together with the main group of the Iranian strains; (4) strains isolated from Korea; (5) strains of pathotype E; and (6) seven strains from Iran which made a completely separate cluster. Strains from pathotypes B and D could not be differentiated by AFLP. The tested Iranian strains belongs to the two different groups and strains from Korea grouped as a subcluster from main cluster of Iranian strains belong to the pathotype A.

  6. The structure of a Xanthomonas general stress protein involved in citrus canker reveals its flavin-binding property.

    PubMed

    Hilario, Eduardo; Li, Yang; Niks, Dimitri; Fan, Li

    2012-07-01

    Xanthomonas citri pv. citri (Xac) causes citrus canker and affects citrus agriculture worldwide. Functional genetic analysis has indicated that a putative general stress protein (XacGSP) encoded by the Xac2369 gene is involved in the bacterial infection. In this report, the crystal structure of XacGSP was determined to 2.5 Å resolution. There are four XacGSP molecules in the crystal asymmetric unit. Each XacGSP monomer folds into a six-stranded antiparallel β-barrel flanked by five α-helices. A C-terminal extension protrudes from the sixth β-strand of the β-barrel and pairs with its counterpart from another monomer to form a bridge between the two subunits of an XacGSP dimer. Two XacGSP dimers cross over each other to form a tetramer; the β-barrels from one dimer contact the β-barrels of the other, while the two bridges are distant from each other and do not make contacts. The three-dimensional structure of the XacGSP monomer is very similar to those of pyridoxine 5-phosphate oxidases, a group of enzymes that use flavin mononucleotide (FMN) as a cofactor. Consistent with this, purified XacGSP protein binds to both FMN and flavin adenine dinucleotide (FAD), suggesting that XacGSP may help the bacteria to react against the oxidative stress induced by the defense mechanisms of the plant.

  7. Bacterial canker on kiwifruit in Italy: anatomical changes in the wood and in the primary infection sites.

    PubMed

    Renzi, Marsilio; Copini, Paul; Taddei, Anna R; Rossetti, Antonio; Gallipoli, Lorenzo; Mazzaglia, Angelo; Balestra, Giorgio M

    2012-09-01

    The bacterial canker of kiwifruit caused by Pseudomonas syringae pv. actinidiae is a severe threat to kiwifruit production worldwide. Many aspects of P. syringae pv. actinidiae biology and epidemiology still require in-depth investigation. The infection by and spread of P. syringae pv. actinidiae in xylem and phloem was investigated by carrying out artificial inoculation experiments with histological and dendrochronological analyses of naturally diseased plants in Italy. We found that the bacterium can infect host plants by entering natural openings and lesions. In naturally infected kiwifruit plants, P. syringae pv. actinidiae is present in the lenticels as well as in the dead phloem tissue beneath the lenticels, surrounded by a lesion in the periderm which appears to indicate the importance of lenticels to kiwifruit infection. Biofilm formation was observed outside and inside plants. In cases of advanced stages of P. syringae pv. actinidiae infection, neuroses of the phloem occur, which are followed by cambial dieback and most likely by infection of the xylem. Anatomical changes in wood such as reduced ring width, a drastic reduction in vessel size, and the presence of tyloses were observed within several infected sites. In the field, these changes occur only a year after the first leaf symptoms are observed suggesting a significant time lapse between primary and secondary symptoms. It was possible to study the temporal development of P. syringae pv. actinidiae-induced cambial dieback by applying dendrochronology methods which revealed that cambial dieback occurs only during the growing season.

  8. Solanapyrone analogues from a Hawaiian fungicolous fungus

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Four new solanayrone analogues (solanapyrones J-M; 1-4) have been isolated from an unidentified fungicolous fungus collected in Hawaii. The structures and relative configurations of these compounds were determined by analysis of ID NMR, 2D NMR, and MS data. Solanapyrone J(1) showed antifungal acti...

  9. Less-Frequent Fusarium Species of Clinical Interest: Correlation between Morphological and Molecular Identification and Antifungal Susceptibility▿

    PubMed Central

    Azor, Mónica; Gené, Josepa; Cano, Josep; Manikandan, Palanisamy; Venkatapathy, Narendran; Guarro, Josep

    2009-01-01

    Forty-eight Fusarium isolates morphologically identified as belonging to seven species of clinical interest (i.e., Fusarium chlamydosporum, Fusarium dimerum, Fusarium incarnatum, Fusarium napiforme, Fusarium nygamai, Fusarium proliferatum, and Fusarium sacchari) were characterized molecularly by the analysis of the sequences of the TUB region of the β-tubulin gene. F. chlamydosporum and F. dimerum were the most genetically heterogeneous species. A high degree of correlation between the morphological and molecular identification was shown among the isolates studied. A table with the key morphological features for the identification of these Fusarium species is provided. The antifungal susceptibilities of the Fusarium isolates to 11 antifungal drugs were tested; terbinafine was the most active drug against all the species tested with the exception of F. incarnatum, for which amphotericin B was the most active. PMID:19321723

  10. Development of a selective culture medium for Fusarium moniliforme.

    PubMed

    Castellá, G; Bragulat, M R; Rubiales, M V; Cabañes, F J

    1997-12-01

    Nash and Snyder medium and malachite green agar 2.5 ppm medium, a new selective culture medium designed in our laboratory, were challenged with pure cultures of Fusarium moniliforme strains and two different mixed-conidium suspensions, which included rapidly spreading fungi, for their utility in the isolation and enumeration of F. moniliforme. From the results of this comparative study, malachite green agar 2.5 ppm allowed only the selective growth of F. moniliforme whereas Nash and Snyder medium allowed both the growth of F. moniliforme and other species not belonging to Fusarium spp. The enumeration of F. moniliforme propagules was similar in both culture media.

  11. Identification of Fusarium species isolated from stored apple fruit in Croatia.

    PubMed

    Sever, Zdravka; Ivić, Dario; Kos, Tomislav; Miličević, Tihomir

    2012-12-01

    Several species of the genus Fusarium can cause apple fruit to rot while stored. Since Fusarium taxonomy is very complex and has constantly been revised and updated over the last years, the aim of this study was to identify Fusarium species from rotten apples, based on combined morphological characteristics and molecular data. We identified 32 Fusarium isolates from rotten apple fruit of cultivars Golden Delicious, Jonagold, Idared, and Pink Lady, stored in Ultra Low Oxygen (ULO) conditions. Fusarium rot was detected in 9.4 % to 33.2 % of naturally infected apples, depending on the cultivar. The symptoms were similar in all four cultivars: a soft circular brown necrosis of different extent, with or without visible sporulation. Fusarium species were identified by the morphology of cultures grown on potato-dextrose agar (PDA) and carnation leaf agar (CLA). Twenty one isolates were identified as Fusarium avenaceum and confirmed as such with polymerase chain reaction (PCR) using specific primer pair FA-ITSF and FA-ITSR. F. pseudograminearum,F. semitectum, F. crookwellense, and F. compactum were identified by morphological characteristics. F.avenaceum can produce several mycotoxins and its dominance in Fusarium rot points to the risk of mycotoxin contamination of apple fruit juices and other products for human consumption. Pathogenicity tests showed typical symptoms of Fusarium rot in most of the inoculated wounded apple fruits. In this respect Fusarium avenaceum, as the dominant cause of Fusarium rot in stored apple fruits is a typical wound parasite.

  12. Two Cdc2 Kinase Genes with Distinct Functions in Vegetative and Infectious Hyphae in Fusarium graminearum

    PubMed Central

    Liu, Huiquan; Zhang, Shijie; Ma, Jiwen; Dai, Yafeng; Li, Chaohui; Lyu, Xueliang; Wang, Chenfang; Xu, Jin-Rong

    2015-01-01

    Eukaryotic cell cycle involves a number of protein kinases important for the onset and progression through mitosis, most of which are well characterized in the budding and fission yeasts and conserved in other fungi. However, unlike the model yeast and filamentous fungi that have a single Cdc2 essential for cell cycle progression, the wheat scab fungus Fusarium graminearum contains two CDC2 orthologs. The cdc2A and cdc2B mutants had no obvious defects in growth rate and conidiation but deletion of both of them is lethal, indicating that these two CDC2 orthologs have redundant functions during vegetative growth and asexual reproduction. However, whereas the cdc2B mutant was normal, the cdc2A mutant was significantly reduced in virulence and rarely produced ascospores. Although deletion of CDC2A had no obvious effect on the formation of penetration branches or hyphopodia, the cdc2A mutant was limited in the differentiation and growth of infectious growth in wheat tissues. Therefore, CDC2A plays stage-specific roles in cell cycle regulation during infectious growth and sexual reproduction. Both CDC2A and CDC2B are constitutively expressed but only CDC2A was up-regulated during plant infection and ascosporogenesis. Localization of Cdc2A- GFP to the nucleus but not Cdc2B-GFP was observed in vegetative hyphae, ascospores, and infectious hyphae. Complementation assays with chimeric fusion constructs showed that both the N- and C-terminal regions of Cdc2A are important for its functions in pathogenesis and ascosporogenesis but only the N-terminal region is important for its subcellular localization. Among the Sordariomycetes, only three Fusarium species closely related to F. graminearum have two CDC2 genes. Furthermore, F. graminearum uniquely has two Aurora kinase genes and one additional putative cyclin gene, and its orthologs of CAK1 and other four essential mitotic kinases in the budding yeast are dispensable for viability. Overall, our data indicate that cell cycle

  13. Uptake of the Fusarium Effector Avr2 by Tomato Is Not a Cell Autonomous Event

    PubMed Central

    Di, Xiaotang; Gomila, Jo; Ma, Lisong; van den Burg, Harrold A.; Takken, Frank L. W.

    2016-01-01

    Pathogens secrete effector proteins to manipulate the host for their own proliferation. Currently it is unclear whether the uptake of effector proteins from extracellular spaces is a host autonomous process. We study this process using the Avr2 effector protein from Fusarium oxysporum f. sp. lycopersici (Fol). Avr2 is an important virulence factor that is secreted into the xylem sap of tomato following infection. Besides that, it is also an avirulence factor triggering immune responses in plants carrying the I-2 resistance gene. Recognition of Avr2 by I-2 occurs inside the plant nucleus. Here, we show that pathogenicity of an Avr2 knockout Fusarium (FolΔAvr2) strain is fully complemented on transgenic tomato lines that express either a secreted (Avr2) or cytosolic Avr2 (ΔspAvr2) protein, indicating that Avr2 exerts its virulence functions inside the host cells. Furthermore, our data imply that secreted Avr2 is taken up from the extracellular spaces in the presence of the fungus. Grafting studies were performed in which scions of I-2 tomato plants were grafted onto either a ΔspAvr2 or on an Avr2 rootstock. Although the Avr2 protein could readily be detected in the xylem sap of the grafted plant tissues, no I-2-mediated immune responses were induced suggesting that I-2-expressing tomato cells cannot autonomously take up the effector protein from the xylem sap. Additionally, ΔspAvr2 and Avr2 plants were crossed with I-2 plants. Whereas ΔspAvr2/I-2 F1 plants showed a constitutive immune response, immunity was not triggered in the Avr2/I-2 plants confirming that Avr2 is not autonomously taken up from the extracellular spaces to trigger I-2. Intriguingly, infiltration of Agrobacterium tumefaciens in leaves of Avr2/I-2 plants triggered I-2 mediated cell death, which indicates that Agrobacterium triggers effector uptake. To test whether, besides Fol, effector uptake could also be induced by other fungal pathogens the ΔspAvr2 and Avr2 transgenic lines were inoculated

  14. Fusarial toxins: secondary metabolites of Fusarium fungi.

    PubMed

    Nesic, Ksenija; Ivanovic, Snezana; Nesic, Vladimir

    2014-01-01

    Exposure to mycotoxins occurs worldwide, even though there are geographic and climatic differences in the amounts produced and occurrence of these substances.Mycotoxins are secondary chemical metabolites of different fungi. They are natural contaminants of cereals, so their presence is often inevitable. Among many genera that produce mycotoxins, Fusarium fungi are the most widespread in cereal-growing areas of the planet. Fusarium fungi produce a diversity of mycotoxin types, whose distributions are also diverse. What is produced and where it is produced is influenced primarily by environmental conditions, and crop production and storage methods. The amount of toxin produced depends on physical (viz., moisture, relative humidity, temperature, and mechanical damage), chemical (viz., carbon dioxide,oxygen, composition of substrate, insecticides and fungicides), and biological factors (viz., plant variety, stress, insects, spore load, etc.). Moisture and temperature have a major influence on mold growth rate and mycotoxin production.Among the most toxic and prevalent fusaria) toxins are the following: zearalenone,fumonisins, moniliformin and trichothecenes (T-2/HT-2 toxin, deoxynivalenol,diacetoxyscirpenol, nivalenol). Zearalenone (ZEA; ZON, F-2 toxin) isaphy to estrogenic compound, primarily a field contaminant, which exhibits estrogenic activity and has been implicated in numerous mycotoxicoses of farm animals,especially pigs. Recently, evidence suggests that ZEA has potential to stimulate the growth of human breast cancer cells. Fumonisins are also cancer-promoting metabolites,of which Fumonisin 8 I (FBI) is the most important. Moniliformin (MON) isalso highly toxic to both animals and humans. Trichothecenes are classified as gastrointestinal toxins, dermatotoxins, immunotoxins, hematotoxins, and gene toxins.T-2 and HT-2 toxin, and diacetoxyscirpenol (DAS, anguidine) are the most toxic mycotoxins among the trichothecene group. Deoxynivalenol (DON, vomitoxin) and

  15. Root exudates of mycorrhizal tomato plants exhibit a different effect on microconidia germination of Fusarium oxysporum f. sp. lycopersici than root exudates from non-mycorrhizal tomato plants.

    PubMed

    Scheffknecht, S; Mammerler, R; Steinkellner, S; Vierheilig, H

    2006-07-01

    The effect of root exudates from mycorrhizal and non-mycorrhizal tomato plants on microconidia germination of the tomato pathogen Fusarium oxysporum f. sp. lycopersici was tested. Microconidia germination was enhanced in the presence of root exudates from mycorrhizal tomato plants. The more tomato plants were colonized by the arbuscular mycorrhizal fungus Glomus mosseae, the more microconidia germination was increased, indicating that alterations of the exudation pattern depended on the degree of root AM colonization. Moreover, alterations of the exudation pattern of mycorrhizal plants are not only local, but also systemic. Testing the exudates from plants with a high and a low P level revealed that the alterations of the root exudates from mycorrhizal plants, resulting in a changed effect on microconidia germination, are not due to an improved P status of mycorrhizal plants.

  16. Antifungal, Phytotoxic, and Cytotoxic Activities of Metabolites from Epichloë bromicola, a Fungus Obtained from Elymus tangutorum Grass.

    PubMed

    Song, Qiu-Yan; Nan, Zhi-Biao; Gao, Kun; Song, Hui; Tian, Pei; Zhang, Xing-Xu; Li, Chun-Jie; Xu, Wen-Bo; Li, Xiu-Zhang

    2015-10-14

    The development of high-quality herbage is an important aspect of animal husbandry. Inoculating beneficial fungi onto inferior grass is a feasible strategy for producing new varieties of high-quality herbage. Epichloë bromicola is a candidate fungus that is isolated from Elymus tangutorum. A total of 17 metabolites, 1-17, were obtained from E. bromicola, and their biological activities were assayed. Metabolite 1 exhibited antifungal activities against Alternaria alternata, Fusarium avenaceum, Bipolaris sorokiniana, and Curvularia lunata. EC50 values ranged from 0.7 to 5.3 μM, which were better than the positive control, chlorothalonil. Metabolite 8 displayed obvious phytotoxic effects toward Lolium perenne and Poa crymophila seedlings, and it was as active as glyphosate. None of these isolated metabolites displayed cytotoxicity against Madin-Darby bovine kidney cells. The IC50 values were greater than 100 μM, and the metabolites increased the growth of the cells at a concentration of 12.5 μM. The bioassay indicated that E. bromicola may be a beneficial fungus for producing new varieties of herbage with various resistances. Additionally, metabolite 7, 3-(2'-(4″-hydroxyphenyl)acetoxy)-2S-methylpropanoic acid, is a new natural product, and its stereochemistry was determined by means of optical rotation computation and chemical reactions.

  17. Primary Metabolism of Chickpea Is the Initial Target of Wound Inducing Early Sensed Fusarium oxysporum f. sp. ciceri Race I

    PubMed Central

    Gupta, Sumanti; Chakraborti, Dipankar; Sengupta, Anindita; Basu, Debabrata; Das, Sampa

    2010-01-01

    Background Biotrophic interaction between host and pathogen induces generation of reactive oxygen species that leads to programmed cell death of the host tissue specifically encompassing the site of infection conferring resistance to the host. However, in the present study, biotrophic relationship between Fusarium oxysporum and chickpea provided some novel insights into the classical concepts of defense signaling and disease perception where ROS (reactive oxygen species) generation followed by hypersensitive responses determined the magnitude of susceptibility or resistant potentiality of the host. Methodology/Principal Findings Microscopic observations detected wound mediated in planta pathogenic establishment and its gradual progression within the host vascular tissue. cDNA-AFLP showed differential expression of many defense responsive elements. Real time expression profiling also validated the early recognition of the wound inducing pathogen by the host. The interplay between fungus and host activated changes in primary metabolism, which generated defense signals in the form of sugar molecules for combating pathogenic encounter. Conclusions/Significance The present study showed the limitations of hypersensitive response mediated resistance, especially when foreign encounters involved the food production as well as the translocation machinery of the host. It was also predicted from the obtained results that hypersensitivity and active species generation failed to impart host defense in compatible interaction between chickpea and Fusarium. On the contrary, the defense related gene(s) played a critical role in conferring natural resistance to the resistant host. Thus, this study suggests that natural selection is the decisive factor for selecting and segregating out the suitable type of defense mechanism to be undertaken by the host without disturbing its normal metabolism, which could deviate from the known classical defense mechanisms. PMID:20140256

  18. Ant-fungus species combinations engineer physiological activity of fungus gardens.

    PubMed

    Seal, J N; Schiøtt, M; Mueller, U G

    2014-07-15

    Fungus-gardening insects are among the most complex organisms because of their extensive co-evolutionary histories with obligate fungal symbionts and other microbes. Some fungus-gardening insect lineages share fungal symbionts with other members of their lineage and thus exhibit diffuse co-evolutionary relationships, while others exhibit little or no symbiont sharing, resulting in host-fungus fidelity. The mechanisms that maintain this symbiont fidelity are currently unknown. Prior work suggested that derived leaf-cutting ants in the genus Atta interact synergistically with leaf-cutter fungi (Attamyces) by exhibiting higher fungal growth rates and enzymatic activities than when growing a fungus from the sister-clade to Attamyces (so-called 'Trachymyces'), grown primarily by the non-leaf cutting Trachymyrmex ants that form, correspondingly, the sister-clade to leaf-cutting ants. To elucidate the enzymatic bases of host-fungus specialization in leaf-cutting ants, we conducted a reciprocal fungus-switch experiment between the ant Atta texana and the ant Trachymyrmex arizonensis and report measured enzymatic activities of switched and sham-switched fungus gardens to digest starch, pectin, xylan, cellulose and casein. Gardens exhibited higher amylase and pectinase activities when A. texana ants cultivated Attamyces compared with Trachymyces fungi, consistent with enzymatic specialization. In contrast, gardens showed comparable amylase and pectinase activities when T. arizonensis cultivated either fungal species. Although gardens of leaf-cutting ants are not known to be significant metabolizers of cellulose, T. arizonensis were able to maintain gardens with significant cellulase activity when growing either fungal species. In contrast to carbohydrate metabolism, protease activity was significantly higher in Attamyces than in Trachymyces, regardless of the ant host. Activity of some enzymes employed by this symbiosis therefore arises from complex interactions between the

  19. Root Rot of Balloon Flower (Platycodon grandiflorum) Caused by Fusarium solani and Fusarium oxysporum.

    PubMed

    Jeon, Chi Sung; Kim, Gyoung Hee; Son, Kyeong In; Hur, Jae-Seoun; Jeon, Kwon-Seok; Yoon, Jun-Hyuck; Koh, Young Jin

    2013-12-01

    Balloon flower (Platycodon grandiflorum) is a kind of mountain herbs whose roots have restorative properties and the cultivating acreage of balloon flower has been steadily increasing in Korea. More frequent rain and high amount of rainfalls as a result of climate changes predisposed balloon flower to the outbreaks of root rot at high-density cultivation area in recent years. Root crowns were usually discolored into brown to blackish brown at first and the infected plants showed slight wilting symptom at early infection stage. Severely infected roots were entirely rotted and whole plants eventually died at late infection stage. The overall disease severities of root rot of balloon flower were quite variable according to the surveyed fields in Jeonnam, Gyeongnam and Jeju Provinces, which ranged from 0.1% to 40%. The root rot occurred more severely at the paddy or clay soils than the sandy soils and their severities were much higher at lowland than upland in the same localty. The disease increased with aging of the balloon flower. The causal fungi were identified as Fusarium solani and F. oxysporum on the basis of their mycological characteristics. The optimum temperature ranges of their mycelial growths was found to be 24°C. The pathogenic characters of F. solani and F. oxysporum treated by artificial wounding inoculation on healthy roots of balloon flower revealed that F. solani was more virulent than F. oxysporum. This study identified the causal agents of root rot of balloon flower as Fusarium solani and F. oxysporum, probably for the first time.

  20. Reduced susceptibility to Fusarium head blight in Brachypodium distachyon through priming with the Fusarium mycotoxin deoxynivalenol.

    PubMed

    Blümke, Antje; Sode, Björn; Ellinger, Dorothea; Voigt, Christian A

    2015-06-01

    The fungal cereal pathogen Fusarium graminearum produces deoxynivalenol (DON) during infection. The mycotoxin DON is associated with Fusarium head blight (FHB), a disease that can cause vast grain losses. Whilst investigating the suitability of Brachypodium distachyon as a model for spreading resistance to F. graminearum, we unexpectedly discovered that DON pretreatment of spikelets could reduce susceptibility to FHB in this model grass. We started to analyse the cell wall changes in spikelets after infection with F. graminearum wild-type and defined mutants: the DON-deficient Δtri5 mutant and the DON-producing lipase disruption mutant Δfgl1, both infecting only directly inoculated florets, and the mitogen-activated protein (MAP) kinase disruption mutant Δgpmk1, with strongly decreased virulence but intact DON production. At 14 days post-inoculation, the glucose amounts in the non-cellulosic cell wall fraction were only increased in spikelets infected with the DON-producing strains wild-type, Δfgl1 and Δgpmk1. Hence, we tested for DON-induced cell wall changes in B. distachyon, which were most prominent at DON concentrations ranging from 1 to 100 ppb. To test the involvement of DON in defence priming, we pretreated spikelets with DON at a concentration of 1 ppm prior to F. graminearum wild-type infection, which significantly reduced FHB disease symptoms. The analysis of cell wall composition and plant defence-related gene expression after DON pretreatment and fungal infection suggested that DON-induced priming of the spikelet tissue contributed to the reduced susceptibility to FHB.

  1. Gibberella moniliformis AH13 with antitumor activity, an endophytic fungus strain producing triolein isolated from Adlay (Coix lacryma-jobi: poaceae).

    PubMed

    Jia, Min; Ming, Qian-Liang; Zhang, Qiao-Yan; Chen, Yu; Cheng, Nuo; Wu, Wen-wen; Han, Ting; Qin, Lu-Ping

    2014-09-01

    In this study, the isolation of an endophytic fungus from the leaves of the medicinal herb adlay (Coix lacryma-jobi L. var. ma-yuen Stapf) is reported for the first time. The fungus produced Triolein (trioleoylglycerol), a major constituent of triacylglycerols (TAGs) of adlay, in rice medium under shake-flask and bench-scale fermentation conditions. The fungus was identified as Gibberella moniliformis (Fusarium verticillioides) by its morphology and authenticated by ITS analysis (ITS1 and ITS2 regions and the intervening 5.8S rDNA region). Triolein was identified by HPLC-ELSD coupled with APCI-MS and confirmed through comparison with authentic standard. The concentration of triolein produced by G. moniliformis AH13 reached 2.536 ± 0.006 mg/g dry weight of mycelium. Moreover, the EtOAc extract of G. moniliformis AH13 showed strong antitumor activity against four types of tumor cells (A549, HCT116, MDA-MB-231, and SW1990). These results suggest that G. moniliformis AH13 in adlay has significant scientific and industrial potential to meet the pharmaceutical demands and sustainable energy requirements for TAGs in a cost-effective, easily accessible, and reproducible way and is also a potential novel source of natural antitumor bioactive agents.

  2. Four-locus phylogeny of Fusarium avenaceum and related species and their species-specific identification based on partial phosphate permease gene sequences.

    PubMed

    Stakheev, Alexander A; Khairulina, Dina R; Zavriev, Sergey K

    2016-05-16

    The fungus Fusarium avenaceum and its closest relatives are responsible for contamination of agricultural plants and their products by mycotoxins such as enniatins and moniliformin. Precise identification of mycotoxin producers is necessary for estimation of the accumulation risk of those compounds and for preventing the consumption of highly contaminated products. Nucleic acids amplification-based techniques proved to be the most rapid and reliable approach for pathogen diagnostics and identification. In this study partial phosphate permease gene (PHO) sequences were determined for Fusarium avenaceum (including one isolate identified as F. arthrosporioides), F. tricinctum, F. acuminatum and F. torulosum. Phylogenetic analysis of 40 isolates of those species from different climates and geographical regions of Russia and some neighboring countries based on sequences of PHO, translation elongation factor 1 alpha (TEF1α), beta-tubulin (β-TUB), enniatin synthetase (Esyn1) genes and combined data set demonstrated that the PHO gene possesses the highest rate of variability among them and can be considered as an informative marker for phylogenetic studies of these species. According to the combined data set phylogeny, the isolates of each species formed clusters with a high bootstrap support. Analysis of PHO sequences revealed a high intraspecific variability of F. avenaceum: there were 5 independent clusters on the dendrogram, including one cluster which was closer to F. torulosum than to other F. avenaceum isolates. Variable sites in PHO sequences have been used for the design of species-specific primers and a fluorescent hydrolysis probe. The specificity of the assay was shown for DNA samples extracted from 68 isolates of 23 Fusarium species. Quantitative PCR approach was applied to estimate the contamination rate of 17 naturally infected oat and barley samples, previously characterized by microbiological procedures.

  3. Antifungal Effect of Essential Oils against Fusarium Keratitis Isolates.

    PubMed

    Homa, Mónika; Fekete, Ildikó Pálma; Böszörményi, Andrea; Singh, Yendrembam Randhir Babu; Selvam, Kanesan Panneer; Shobana, Coimbatore Subramanian; Manikandan, Palanisamy; Kredics, László; Vágvölgyi, Csaba; Galgóczy, László

    2015-09-01

    The present study was carried out to investigate the antifungal effects of Cinnamomum zeylanicum, Citrus limon, Juniperus communis, Eucalyptus citriodora, Gaultheria procumbens, Melaleuca alternifolia, Origanum majorana, Salvia sclarea, and Thymus vulgaris essential oils against Fusarium species, the most common etiologic agents of filamentous fungal keratitis in South India. C. zeylanicum essential oil showed strong anti-Fusarium activity, whereas all the other tested essential oils proved to be less effective. The main component of C. zeylanicum essential oil, trans-cinnamaldehyde, was also tested and showed a similar effect as the oil. The in vitro interaction between trans-cinnamaldehyde and natamycin, the first-line therapeutic agent of Fusarium keratitis, was also investigated; an enhanced fungal growth inhibition was observed when these agents were applied in combination. Light and fluorescent microscopic observations revealed that C. zeylanicum essential oil/trans-cinnamaldehyde reduces the cellular metabolism and inhibits the conidia germination. Furthermore, necrotic events were significantly more frequent in the presence of these two compounds. According to our results, C. zeylanicum essential oil/trans-cinnamaldehyde provides a promising basis to develop a novel strategy for the treatment of Fusarium keratitis.

  4. Effects of xanthotoxin treatment on trichothecene production in Fusarium sporotrichioides

    Technology Transfer Automated Retrieval System (TEKTRAN)

    There are four P450 oxygenases involved in the biosynthesis of T-2 toxin in Fusarium sporotrichioides. Exactly how these enzymes react to antimicrobial plant defense compounds is unknown. Xanthotoxin (8-methoxypsoralen), a phototoxic furanocoumarin, is a P450 oxygenase inhibitor. A previous study...

  5. Annotation of Fusarium graminearum (PH-1) Version 5.0

    PubMed Central

    Hammond-Kosack, Kim E.

    2017-01-01

    ABSTRACT Fusarium graminearum floral infections are a major risk to the global supply of safe cereal grains. We report updates to the PH-1 reference genome and significant improvements to the annotation. Changes include introduction of legacy annotation identifiers, new gene models, secretome and effectorP predictions, and inclusion of extensive untranslated region (UTR) annotations. PMID:28082505

  6. Presence of Fusarium graminearum in air associated with sorghum fields

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Sorghum can be included in crop rotations with wheat. However, there are no known reports on the effects of sorghum grown in rotation with wheat on the epidemiology of head scab caused by Fusarium graminearum. Conidia in air samples within two sorghum fields were collected by passive spore trapping ...

  7. Cytotoxicity and Phytotoxicity of Trichothecene Mycotoxins Produced by Fusarium spp.

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Trichothecenes, a major class of mycotoxins produced by Fusarium, Myrothecium, and Stachybotrys species, are toxic to plants, causing blights, wilts and other economically-important plant diseases, and to mammals, for example feed-refusal caused by deoxynivalenol (vomitoxin). Macrocyclic trichothec...

  8. Controlling fusarium wilt of California strawberries by anaerobic soil disinfestation

    Technology Transfer Automated Retrieval System (TEKTRAN)

    In the 2014-15 season, the ASD-treated berry acreage exceeded 1,000 acres in California; more than doubled from the previous season. Fusarium wilt an emerging lethal disease of strawberries in California, can also be controlled by ASD. However, a study has shown that higher soil temperatures are n...

  9. Distribution and evolution of fusarin mycotoxin biosynthetic genes in Fusarium

    Technology Transfer Automated Retrieval System (TEKTRAN)

    In Fusarium/Gibberella, secondary metabolite biosynthetic (SMB) genes that have a narrow distribution within the genus can have complex evolutionary histories. Whether more widely distributed SMB genes have similarly complex histories is not known. Genes responsible for production of fusarin mycot...

  10. VeA regulates some secondary metabolism in Fusarium fujikuroi

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Fusarium fujikuroi is a pathogen of rice that causes hyper elongation of seedling stalks and leaves due to the fungal production of gibberellic acids (GAs). During infection of rice or after growth on other cereals, F. fujikuroi may also synthesize other toxins (e.g. fumonisins, fusarin C, and bika...

  11. [Fusarium pleural effusion after a ventricular assist device].

    PubMed

    Villacorta, J; Blancard, A; Kerbaul, F; Guidon, C; Gouin, F

    2002-05-01

    We report the case of a 36-year-old man with a pleural effusion that complicates the postoperative period after the implantation of a ventricular assist device (VAD). The epidemiological, etiologic and therapeutic features of Fusarium infections were reviewed. Complete recovery of the infection was obtained after a treatment by liposomal amphotericine B (AmBisome) and 5 fluorocytosine.

  12. Proposal for a new ISHAM Working group on Clinical Fusarium

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Infections caused by Fusarium species can be classified in three classes: 1) Superficial infections of skin and nails; 2) Keratitis of the cornea; and 3) Deep and disseminated infections. Whereas the first two types of these opportunistic infections are generally seen in immunocompetent hosts, the d...

  13. The transcriptome of Fusarium graminearum during the infection of wheat

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Fusarium graminearum causes head blight disease in wheat and barley. To help understand the infection process on wheat we studied global gene expression of F. graminearum in a time series from 24 to 196 hours after inoculation, compared to a water control. The infection is rapid and already after 48...

  14. Fusarium verticillioides gene expression profiling by microarray analysis

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Fusarium verticillioides is a pathogen of maize and it can produce the toxic polyketide derived secondary metabolites called fumonisins. Fumonisins have been shown to cause animal diseases and are epidemiologically correlated to esophageal cancer and neural tube defects in humans. The genes necess...

  15. Phylogenomic and functional domain analysis of polyketide synthases in Fusarium

    SciTech Connect

    Brown, Daren W.; Butchko, Robert A.; Baker, Scott E.; Proctor, Robert H.

    2012-02-01

    Fusarium species are ubiquitous in nature, cause a range of plant diseases, and produce a variety of chemicals often referred to as secondary metabolites. Although some fungal secondary metabolites affect plant growth or protect plants from other fungi and bacteria, their presence in grain based food and feed is more often associated with a variety of diseases in plants and in animals. Many of these structurally diverse metabolites are derived from a family of related enzymes called polyketide synthases (PKSs). A search of genomic sequence of Fusarium verticillioides, F. graminearum, F. oxysporum and Nectria haematococca (anamorph F. solani) identified a total of 58 PKS genes. To gain insight into how this gene family evolved and to guide future studies, we conducted a phylogenomic and functional domain analysis. The resulting genealogy suggested that Fusarium PKSs represent 34 different groups responsible for synthesis of different core metabolites. The analyses indicate that variation in the Fusarium PKS gene family is due to gene duplication and loss events as well as enzyme gain-of-function due to the acquisition of new domains or of loss-of-function due to nucleotide mutations. Transcriptional analysis indicate that the 16 F. verticillioides PKS genes are expressed under a range of conditions, further evidence that they are functional genes that confer the ability to produce secondary metabolites.

  16. Incidence of Fusarium species and mycotoxins in silage maize.

    PubMed

    Eckard, Sonja; Wettstein, Felix E; Forrer, Hans-Rudolf; Vogelgsang, Susanne

    2011-08-01

    Maize is frequently infected by the Fusarium species producing mycotoxins. Numerous investigations have focused on grain maize, but little is known about the Fusarium species in the entire plant used for silage. Furthermore, mycotoxins persist during the ensiling process and thus endanger feed safety. In the current study, we analyzed 20 Swiss silage maize samples from growers' fields for the incidence of Fusarium species and mycotoxins. The species spectrum was analyzed morphologically and mycotoxins were measured by LC-MS/MS. A pre-harvest visual disease rating showed few disease symptoms. In contrast, the infection rate of two-thirds of the harvest samples ranged from 25 to 75% and twelve different Fusarium species were isolated. The prevailing species were F. sporotrichioides, F. verticillioides and F. graminearum. No infection specificity for certain plant parts was observed. The trichothecene deoxynivalenol (DON) was found in each sample (ranging from 780 to 2990 µg kg(-1)). Other toxins detected in descending order were zearalenone, further trichothecenes (nivalenol, HT-2 and T-2 toxin, acetylated DON) and fumonisins. A generalized linear regression model containing the three cropping factors harvest date, pre-precrop and seed treatment was established, to explain DON contamination of silage maize. Based on these findings, we suggest a European-wide survey on silage maize.

  17. Quantitative and Qualitative Analysis of Biomarkers in Fusarium verticillioides

    Technology Transfer Automated Retrieval System (TEKTRAN)

    In this study, a combination HPLC-DART-TOF-MS system was utilized to identify and quantitatively analyze carbohydrates in wild type and mutant strains of Fusarium verticillioides. Carbohydrate fractions were isolated from F. verticillioides cellular extracts by HPLC using a cation-exchange size-excl...

  18. Comparative Genomics Reveals Mobile Pathogenicity Chromosomes in Fusarium

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Fusarium species are among the most important phytopathogenic and toxigenic fungi, having significant impact on crop production and animal health. Distinctively, strains of F. oxysporum exhibit wide host range and are pathogenic to both plant and animal species, reflecting remarkable genetic adapta...

  19. Global Analysis of Horizontal Gene Transfer in Fusarium verticillioides

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The co-occurrence of microbes within plants and other specialized niches may facilitate horizontal gene transfer (HGT) affecting host-pathogen interactions. We recently identified fungal-to-fungal HGTs involving metabolic gene clusters. For a global analysis of HGTs in the maize pathogen Fusarium ve...

  20. Clonality, recombination, and hybridization in the plumbing-inhabiting human pathogen Fusarium keratoplasticum inferred from multilocus sequence typing

    PubMed Central

    2014-01-01

    Background Recent work has shown that Fusarium species and genotypes most commonly associated with human infections, particularly of the cornea (mycotic keratitis), are the same as those most commonly isolated from plumbing systems. The species most dominant in plumbing biofilms is Fusarium keratoplasticum, a cosmopolitan fungus known almost exclusively from animal infections and biofilms. To better understand its diversity and population dynamics, we developed and utilized a nine-locus sequence-based typing system to make inferences about clonality, recombination, population structure, species boundaries and hybridization. Results High levels of genetic diversity and evidence for recombination and clonality were detected among 75 clinical and 156 environmental isolates of Fusarium keratoplasticum. The multilocus sequence typing system (MLST) resolved 111 unique nine-locus sequence types (STs). The single locus bifactorial determinants of mating compatibility (mating types MAT1-1 and MAT1-2), were found in a ratio of 70:30. All but one of the 49 isolates of the most common ST (FSSC 2d-2) came from human infections, mostly of the cornea, and from biofilms associated with contact lenses and plumbing surfaces. Significant levels of phylogenetic incongruence were found among loci. Putative clonal relationships among genotypes were estimated, showing a mixture of large clonal complexes and unrelated singletons. Discordance between the nuclear ribosomal rRNA and other gene genealogies is consistent with introgression of ribosomal RNA alleles of phylogenetic species FSSC 9 into F. keratoplasticum. No significant population subdivision based on clinical versus non-clinical sources was found. Conclusions Incongruent phylogenetic trees and the presence of both mating types within otherwise identical STs were observed, providing evidence for sexuality in F. keratoplasticum. Cryptic speciation suggested in a published three-locus MLST system was not supported with the addition