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Fierro-Cruz JE, Jiménez P, Coy-Barrera E. Fungal endophytes isolated from Protium heptaphyllum and Trattinnickia rhoifolia as antagonists of Fusarium oxysporum. Rev Argent Microbiol 2017; 49:255-263. [PMID: 28495036 DOI: 10.1016/j.ram.2016.12.009] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/08/2016] [Revised: 08/04/2016] [Accepted: 12/28/2016] [Indexed: 01/25/2023] Open
Abstract
Control of fungal pathogens is mainly addressed by the use of chemically synthesized fungicides which result in environmental pollution, developing resistance after prolonged use. In this context, endophytes have been recognized as potential biocontrollers, and also as a promising source of antifungal metabolites. Therefore, as part of our research on phytopathogen controllers, 355 fungal endophytes were isolated from Protium heptaphyllum and Trattinnickia rhoifolia (Burseraceae), both ethnobotanically important tree species that produce secondary metabolites of agronomic and industrial interest. Endophytes were tested by in vitro dual culture against Fusarium oxysporum, a phytopathogen of agronomic importance. Five endophytes exerted at least 40% inhibition on F. oxysporum growth. Ethyl acetate (EtOAc) extracts were obtained from the most active antagonistic fungi, after growing them in three different liquid media. The extracts were tested against a conidial suspension of F. oxysporum by direct bioautography. Two extracts derived from fungi identified as Chaetomium globosum, F211_UMNG and Meyerozima sp. F281_UMNG showed inhibition of pathogen growth. Isolate C. globosum, F211_UMNG was selected for a chemical analysis by RP-HPLC-DAD-ESI-MS and antifungal molecules such as cladosporin, chaetoatrosin A and chaetoviridin A were annotated and identified based on their MS data.
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Affiliation(s)
- Juan E Fierro-Cruz
- Universidad Militar Nueva Granada, Km 2 Cajicá - Zipaquirá, Cajicá, Colombia
| | - Pedro Jiménez
- Universidad Militar Nueva Granada, Km 2 Cajicá - Zipaquirá, Cajicá, Colombia
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Santhanam R, Oh Y, Kumar R, Weinhold A, Luu VT, Groten K, Baldwin IT. Specificity of root microbiomes in native-grown Nicotiana attenuata and plant responses to UVB increase Deinococcus colonization. Mol Ecol 2017; 26:2543-2562. [PMID: 28173617 DOI: 10.1111/mec.14049] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/04/2016] [Revised: 01/24/2017] [Accepted: 01/29/2017] [Indexed: 01/02/2023]
Abstract
Plants recruit microbial communities from the soil in which they germinate. Our understanding of the recruitment process and the factors affecting it is still limited for most microbial taxa. We analysed several factors potentially affecting root microbiome structure - the importance of geographic location of natural populations, the microbiome of native seeds as putative source of colonization and the effect of a plant's response to UVB exposure on root colonization of highly abundant species. The microbiome of Nicotiana attenuata seeds was determined by a culture-dependent and culture-independent approach, and the root microbiome of natural N. attenuata populations from five different locations was analysed using 454-pyrosequencing. To specifically address the influence of UVB light on root colonization by Deinococcus, a genus abundant and consistently present in N. attenuata roots, transgenic lines impaired in UVB perception (irUVR8) and response (irCHAL) were investigated in a microcosm experiment with/without UVB supplementation using a synthetic bacterial community. The seed microbiome analysis indicated that N. attenuata seeds are sterile. Alpha and beta diversities of native root bacterial communities differed significantly between soil and root, while location had only a significant effect on the fungal but not the bacterial root communities. With UVB supplementation, root colonization of Deinococcus increased in wild type, but decreased in irUVR8 and irCHAL plants compared to nontreated plants. Our results suggest that N. attenuata recruits a core root microbiome exclusively from soil, with fungal root colonization being less selective than bacterial colonization. Root colonization by Deinococcus depends on the plant's response to UVB.
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Affiliation(s)
- Rakesh Santhanam
- Department of Molecular Ecology, Max Planck Institute for Chemical Ecology, Hans-Knöll-Str. 8, Jena, 07745, Germany
| | - Youngjoo Oh
- Department of Molecular Ecology, Max Planck Institute for Chemical Ecology, Hans-Knöll-Str. 8, Jena, 07745, Germany
| | - Ramesh Kumar
- Department of Molecular Ecology, Max Planck Institute for Chemical Ecology, Hans-Knöll-Str. 8, Jena, 07745, Germany
- CSIR - National Institute for Interdisciplinary Science and Technology (NIIST), Industrial Estate Po, Thiruvananthapuram, Kerala, 695019, India
| | - Arne Weinhold
- Department of Molecular Ecology, Max Planck Institute for Chemical Ecology, Hans-Knöll-Str. 8, Jena, 07745, Germany
| | - Van Thi Luu
- Department of Molecular Ecology, Max Planck Institute for Chemical Ecology, Hans-Knöll-Str. 8, Jena, 07745, Germany
| | - Karin Groten
- Department of Molecular Ecology, Max Planck Institute for Chemical Ecology, Hans-Knöll-Str. 8, Jena, 07745, Germany
| | - Ian T Baldwin
- Department of Molecular Ecology, Max Planck Institute for Chemical Ecology, Hans-Knöll-Str. 8, Jena, 07745, Germany
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Cytotoxicity, antioxidant and antibacterial activity of four compounds produced by an endophytic fungus Epicoccum nigrum associated with Entada abyssinica. REVISTA BRASILEIRA DE FARMACOGNOSIA-BRAZILIAN JOURNAL OF PHARMACOGNOSY 2017. [DOI: 10.1016/j.bjp.2016.08.011] [Citation(s) in RCA: 46] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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Mishra VK, Passari AK, Leo VV, Singh BP. Molecular Diversity and Detection of Endophytic Fungi Based on Their Antimicrobial Biosynthetic Genes. Fungal Biol 2017. [DOI: 10.1007/978-3-319-34106-4_1] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
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Fatima N, Kondratyuk TP, Park EJ, Marler LE, Jadoon M, Qazi MA, Mehboob Mirza H, Khan I, Atiq N, Chang LC, Ahmed S, Pezzuto JM. Endophytic fungi associated with Taxus fuana (West Himalayan Yew) of Pakistan: potential bio-resources for cancer chemopreventive agents. PHARMACEUTICAL BIOLOGY 2016; 54:2547-2554. [PMID: 27159021 DOI: 10.3109/13880209.2016.1170154] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/05/2023]
Abstract
CONTEXT Endophytic fungi, being a prolific source of bioactive secondary metabolites, are of great interest for natural product discovery. OBJECTIVE Isolation and partial characterization of endophytic fungi inhabiting the leaves and woody parts of Taxus fuana Nan Li & R.R. Mill. (Taxaceae) and evaluation of biological activity. MATERIALS AND METHODS Endophytic fungal isolates were identified by molecular analysis of internal transcribed spacer (ITS) regions of 18S rDNA. Extracts of the endophytic fungi cultured on potato dextrose agar and modified medium were evaluated using cancer chemoprevention bioassays [inhibition of TNF-α-induced NFκB, aromatase and inducible nitric oxide synthase (iNOS); induction of quinone reductase 1 (QR1)] and growth inhibition with MCF-7 cells. RESULTS Nine of 15 fungal isolates were identified as belonging to Epicoccum, Mucor, Penicillium, Chaetomium, Paraconiothriym, Plectania or Trichoderma. Five of the 15 extracts inhibited NFκB activity (IC50 values ranging between 0.18 and 17 μg/mL) and five inhibited iNOS (IC50 values ranging between 0.32 and 12.9 μg/mL). In the aromatase assay, only two isolates mediated inhibition (IC50 values 12.2 and 10.5 μg/mL). With QR1 induction, three extracts exhibited significant activity (concentrations to double activity values ranging between 0.20 and 5.5 μg/mL), and five extracts inhibited the growth of MCF-7 cells (IC50 values ranging from 0.56 to 17.5 μg/mL). Six active cultures were derived from woody parts of the plant material. CONCLUSION The endophytic fungi studied are capable of producing pharmacologically active natural compounds. In particular, isolates derived from the wood of Taxus fuana should be prioritized for the isolation and characterization of bioactive constituents.
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Affiliation(s)
- Nighat Fatima
- a Department of Biotechnology , Quaid-i-Azam University , Islamabad , Pakistan
- b Department of Microbiology , Quaid-i-Azam University , Islamabad , Pakistan
- c Department of Pharmaceutical Sciences, Daniel K. Inouye College of Pharmacy , University of Hawaii at Hilo , Hilo , HI , USA
| | - Tamara P Kondratyuk
- c Department of Pharmaceutical Sciences, Daniel K. Inouye College of Pharmacy , University of Hawaii at Hilo , Hilo , HI , USA
| | - Eun-Jung Park
- c Department of Pharmaceutical Sciences, Daniel K. Inouye College of Pharmacy , University of Hawaii at Hilo , Hilo , HI , USA
| | - Laura E Marler
- c Department of Pharmaceutical Sciences, Daniel K. Inouye College of Pharmacy , University of Hawaii at Hilo , Hilo , HI , USA
| | - Muniba Jadoon
- b Department of Microbiology , Quaid-i-Azam University , Islamabad , Pakistan
| | - Muneer Ahmed Qazi
- b Department of Microbiology , Quaid-i-Azam University , Islamabad , Pakistan
| | - Hira Mehboob Mirza
- b Department of Microbiology , Quaid-i-Azam University , Islamabad , Pakistan
| | - Ibrar Khan
- b Department of Microbiology , Quaid-i-Azam University , Islamabad , Pakistan
| | - Naima Atiq
- b Department of Microbiology , Quaid-i-Azam University , Islamabad , Pakistan
| | - Leng Chee Chang
- c Department of Pharmaceutical Sciences, Daniel K. Inouye College of Pharmacy , University of Hawaii at Hilo , Hilo , HI , USA
| | - Safia Ahmed
- b Department of Microbiology , Quaid-i-Azam University , Islamabad , Pakistan
| | - John M Pezzuto
- c Department of Pharmaceutical Sciences, Daniel K. Inouye College of Pharmacy , University of Hawaii at Hilo , Hilo , HI , USA
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Lugtenberg BJJ, Caradus JR, Johnson LJ. Fungal endophytes for sustainable crop production. FEMS Microbiol Ecol 2016; 92:fiw194. [PMID: 27624083 DOI: 10.1093/femsec/fiw194] [Citation(s) in RCA: 134] [Impact Index Per Article: 16.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 09/08/2016] [Indexed: 11/12/2022] Open
Abstract
This minireview highlights the importance of endophytic fungi for sustainable agriculture and horticulture production. Fungal endophytes play a key role in habitat adaptation of plants resulting in improved plant performance and plant protection against biotic and abiotic stresses. They encode a vast variety of novel secondary metabolites including volatile organic compounds. In addition to protecting plants against pathogens and pests, selected fungal endophytes have been used to remove animal toxicities associated with fungal endophytes in temperate grasses, to create corn and rice plants that are tolerant to a range of biotic and abiotic stresses, and for improved management of post-harvest control. We argue that practices used in plant breeding, seed treatments and agriculture, often caused by poor knowledge of the importance of fungal endophytes, are among the reasons for the loss of fungal endophyte diversity in domesticated plants and also accounts for the reduced effectiveness of some endophyte strains to confer plant benefits. We provide recommendations on how to mitigate against these negative impacts in modern agriculture.
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Affiliation(s)
- Ben J J Lugtenberg
- Institute of Biology, Leiden University, Sylviusweg 72, 2333 BE Leiden, the Netherlands
| | - John R Caradus
- Grasslanz Technology Limited, PB 11008, Palmerston North, 4442, New Zealand
| | - Linda J Johnson
- Forage Science, AgResearch Limited, PB 11008, Palmerston North, 4442, New Zealand
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Romão-Dumaresq AS, Dourado MN, Fávaro LCDL, Mendes R, Ferreira A, Araújo WL. Diversity of Cultivated Fungi Associated with Conventional and Transgenic Sugarcane and the Interaction between Endophytic Trichoderma virens and the Host Plant. PLoS One 2016; 11:e0158974. [PMID: 27415014 PMCID: PMC4944904 DOI: 10.1371/journal.pone.0158974] [Citation(s) in RCA: 29] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/29/2016] [Accepted: 06/24/2016] [Indexed: 12/23/2022] Open
Abstract
Plant-associated fungi are considered a vast source for biotechnological processes whose potential has been poorly explored. The interactions and diversity of sugarcane, one of the most important crops in Brazil, have been rarely studied, mainly concerning fungal communities and their interactions with transgenic plants. Taking this into consideration, the purpose of this study was, based on culture dependent strategy, to determine the structure and diversity of the fungal community (root endophytes and rhizosphere) associated with two varieties of sugarcane, a non-genetically modified (SP80-1842) variety and its genetically modified counterpart (IMI-1, expressing imazapyr herbicide resistance). For this, the sugarcane varieties were evaluated in three sampling times (3, 10 and 17 months after planting) under two crop management (weeding and herbicide treatments). In addition, a strain of Trichoderma virens, an endophyte isolated from sugarcane with great potential as a biological control, growth promotion and enzyme production agent, was selected for the fungal-plant interaction assays. The results of the isolation, characterization and evaluation of fungal community changes showed that the sugarcane fungal community is composed of at least 35 different genera, mostly in the phylum Ascomycota. Many genera are observed at very low frequencies among a few most abundant genera, some of which were isolated from specific plant sites (e.g., the roots or the rhizosphere). An assessment of the possible effects upon the fungal community showed that the plant growth stage was the only factor that significantly affected the community's structure. Moreover, if transgenic effects are present, they may be minor compared to other natural sources of variation. The results of interaction studies using the Green fluorescent protein (GFP)-expressing T. virens strain T.v.223 revealed that this fungus did not promote any phenotypic changes in the host plant and was found mostly in the roots where it formed a dense mycelial cover and was able to penetrate the intercellular spaces of the root epidermis upper layers. The ability of T. virens to colonize plant roots suggests a potential for protecting plant health, inhibiting pathogens or inducing systemic resistance.
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Affiliation(s)
- Aline Silva Romão-Dumaresq
- Department of Genetics, Escola Superior de Agricultura “Luiz de Queiroz”(ESALQ), University of São Paulo, São Paulo, Brazil
| | - Manuella Nóbrega Dourado
- Department of Genetics, Escola Superior de Agricultura “Luiz de Queiroz”(ESALQ), University of São Paulo, São Paulo, Brazil
- Laboratory of Molecular Biology and Microbial Ecology, Department of Microbiology, Institute of Biomedical Sciences, University of São Paulo, São Paulo, Brazil
| | - Léia Cecilia de Lima Fávaro
- Department of Genetics, Escola Superior de Agricultura “Luiz de Queiroz”(ESALQ), University of São Paulo, São Paulo, Brazil
- Brazilian Agricultural Research Corporation, Embrapa Agroenergy, Brasília, Distrito Federal, Brazil
| | - Rodrigo Mendes
- Department of Genetics, Escola Superior de Agricultura “Luiz de Queiroz”(ESALQ), University of São Paulo, São Paulo, Brazil
- Brazilian Agricultural Research Corporation, Embrapa Environment, Jaguariuna, São Paulo, Brazil
| | - Anderson Ferreira
- Department of Genetics, Escola Superior de Agricultura “Luiz de Queiroz”(ESALQ), University of São Paulo, São Paulo, Brazil
- Brazilian Agricultural Research Corporation, Embrapa Agrosilvopastoral, Sinop, Mato Grosso, Brazil
| | - Welington Luiz Araújo
- Department of Genetics, Escola Superior de Agricultura “Luiz de Queiroz”(ESALQ), University of São Paulo, São Paulo, Brazil
- Laboratory of Molecular Biology and Microbial Ecology, Department of Microbiology, Institute of Biomedical Sciences, University of São Paulo, São Paulo, Brazil
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Production of Gentisyl Alcohol from Phoma herbarum Endophytic in Curcuma longa L. and Its Antagonistic Activity Towards Leaf Spot Pathogen Colletotrichum gloeosporioides. Appl Biochem Biotechnol 2016; 180:1093-1109. [DOI: 10.1007/s12010-016-2154-0] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/20/2016] [Accepted: 06/01/2016] [Indexed: 12/23/2022]
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Stokholm MS, Wulff EG, Zida EP, Thio IG, Néya JB, Soalla RW, Głazowska SE, Andresen M, Topbjerg HB, Boelt B, Lund OS. DNA barcoding and isolation of vertically transmitted ascomycetes in sorghum from Burkina Faso: Epicoccum sorghinum is dominant in seedlings and appears as a common root pathogen. Microbiol Res 2016; 191:38-50. [PMID: 27524652 DOI: 10.1016/j.micres.2016.05.004] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/23/2016] [Revised: 05/10/2016] [Accepted: 05/11/2016] [Indexed: 10/21/2022]
Abstract
Molecular identification of fungal taxa commonly transmitted through seeds of sorghum in Western Africa is lacking. In the present study, farm-saved seeds, collected from four villages in Northern Burkina Faso, were surface sterilized and the distribution of fungal DNA in seeds and seven-day-old seedlings was analyzed by 18S ribosomal DNA (rDNA) amplicon sequencing. More than 99% of the fungal rDNA was found to originate from ascomycetes. The distribution of ascomycetes at species level was subsequently analyzed by barcoding of ITS2 rDNA. Eighteen Operational Taxonomic Units (OTUs) were identified from seedlings, compared to 29 OTUs from seeds. The top-eight most abundant ascomycete OTUs from seedlings were annotated as: Epicoccum sorghinum, Fusarium thapsinum, four different Curvularia spp., Exserohilum rostratum and Alternaria longissima. These OTUs were also present in amplicons from seed samples collected in Central Burkina Faso confirming a common occurrence. E. sorghinum was highly predominant in seedlings both measured by DNA analysis and by isolation. The dominance of E. sorghinum was particularly strong in roots from poorly growing seedlings. Pathogenicity of E. sorghinum isolates was compared to F. thapsinum by inoculation to seeds in vitro. Both fungal species caused significant inhibition of seedling growth (P<0.001) and Koch's postulates were fulfilled. Extensive, dark necrosis in roots was a typical symptom of E. sorghinum, whereas wilting of leaves was caused primarily by F. thapsinum. This study provides the first molecular approach to characterize the seedling mycoflora of sorghum in Western Africa and suggests E. sorghinum as a common root pathogen.
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Affiliation(s)
- Michaela S Stokholm
- Institute of Plant and Environmental Sciences, Faculty of Science, University of Copenhagen, Hoejbakkegaard Allé 13, DK-2630 Taastrup, Denmark
| | - Ednar G Wulff
- Division of Plant Diagnostics, Danish Veterinary and Food Administration, Ministry of Food, Agriculture and Fisheries, Soendervang 4, DK-4100 Ringsted, Denmark
| | - Elisabeth P Zida
- Kamboinsé Research Station, INERA (Institut de l'Environnement et de Recherches Agricoles), 01 P.O. Box 476 Ouagadougou 01, Burkina Faso
| | - Ibié G Thio
- Kamboinsé Research Station, INERA (Institut de l'Environnement et de Recherches Agricoles), 01 P.O. Box 476 Ouagadougou 01, Burkina Faso
| | - James B Néya
- Kamboinsé Research Station, INERA (Institut de l'Environnement et de Recherches Agricoles), 01 P.O. Box 476 Ouagadougou 01, Burkina Faso
| | - Romain W Soalla
- Kamboinsé Research Station, INERA (Institut de l'Environnement et de Recherches Agricoles), 01 P.O. Box 476 Ouagadougou 01, Burkina Faso
| | - Sylwia E Głazowska
- Institute of Plant and Environmental Sciences, Faculty of Science, University of Copenhagen, Hoejbakkegaard Allé 13, DK-2630 Taastrup, Denmark
| | - Marianne Andresen
- Institute of Plant and Environmental Sciences, Faculty of Science, University of Copenhagen, Hoejbakkegaard Allé 13, DK-2630 Taastrup, Denmark
| | - Henrik B Topbjerg
- Department of Agroecology, Science and Technology, Aarhus University, Forsoegsvej 1, DK-4200 Slagelse, Denmark
| | - Birte Boelt
- Department of Agroecology, Science and Technology, Aarhus University, Forsoegsvej 1, DK-4200 Slagelse, Denmark
| | - Ole S Lund
- Institute of Plant and Environmental Sciences, Faculty of Science, University of Copenhagen, Hoejbakkegaard Allé 13, DK-2630 Taastrup, Denmark.
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Santos PJCD, Savi DC, Gomes RR, Goulin EH, Da Costa Senkiv C, Tanaka FAO, Almeida ÁMR, Galli-Terasawa L, Kava V, Glienke C. Diaporthe endophytica and D. terebinthifolii from medicinal plants for biological control of Phyllosticta citricarpa. Microbiol Res 2016; 186-187:153-60. [DOI: 10.1016/j.micres.2016.04.002] [Citation(s) in RCA: 34] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/16/2016] [Revised: 04/04/2016] [Accepted: 04/06/2016] [Indexed: 10/22/2022]
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Kovačec E, Likar M, Regvar M. Temporal changes in fungal communities from buckwheat seeds and their effects on seed germination and seedling secondary metabolism. Fungal Biol 2016; 120:666-78. [PMID: 27109364 DOI: 10.1016/j.funbio.2016.03.003] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/04/2015] [Revised: 03/01/2016] [Accepted: 03/08/2016] [Indexed: 11/29/2022]
Abstract
Seed-associated fungal communities affect multiple parameters of seed quality at all stages of production, from seed development to post-harvest storage and germination. We therefore investigated the diversity and dynamics of fungal communities in the seeds of common buckwheat (Fagopyrum esculentum) and Tartary buckwheat (F. tataricum) from harvest to 1 y of storage. Fungal populations in seeds were relatively stable, comprised mainly of field fungi. Incidence of fungi was most likely determined by fungal interspecies direct interactions, as well as by their synthesis of volatile organic compounds. Most prominent antagonistic interactions were seen for two plant pathogens, Alternaria alternata on Botrytis cinerea. Detrimental effects of the fungi on seed germination and seedling development were related to fungal extracellular enzyme activity, and in particular to amylase, cellulase and, polyphenol oxidase. Polyphenol and tannin concentrations in buckwheat seedlings were related to fungal growth rate and intensity of fungal cellulase activity, respectively, which suggests that physical penetration of the fungi through the host tissues is probably the stimulus for the activation of plant defence reactions in these seedlings.
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Affiliation(s)
- Eva Kovačec
- Department of Biology, Biotechnical Faculty, University of Ljubljana, Ljubljana 1000, Slovenia
| | - Matevž Likar
- Department of Biology, Biotechnical Faculty, University of Ljubljana, Ljubljana 1000, Slovenia
| | - Marjana Regvar
- Department of Biology, Biotechnical Faculty, University of Ljubljana, Ljubljana 1000, Slovenia.
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Campos FF, Sales Junior PA, Romanha AJ, Araújo MSS, Siqueira EP, Resende JM, Alves TMA, Martins-Filho OA, Santos VLD, Rosa CA, Zani CL, Cota BB. Bioactive endophytic fungi isolated from Caesalpinia echinata Lam. (Brazilwood) and identification of beauvericin as a trypanocidal metabolite from Fusarium sp. Mem Inst Oswaldo Cruz 2015; 110:65-74. [PMID: 25742265 PMCID: PMC4371219 DOI: 10.1590/0074-02760140243] [Citation(s) in RCA: 39] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/09/2014] [Accepted: 11/28/2014] [Indexed: 12/20/2022] Open
Abstract
Aiming to identify new sources of bioactive secondary metabolites, we isolated 82
endophytic fungi from stems and barks of the native Brazilian tree Caesalpinia
echinata Lam. (Fabaceae). We tested their ethyl acetate extracts in several in vitro
assays. The organic extracts from three isolates showed antibacterial activity
against Staphylococcus aureus and Escherichia coli [minimal inhibitory concentration
(MIC) 32-64 μg/mL]. One isolate inhibited the growth of Salmonella typhimurium (MIC
64 μg/mL) and two isolates inhibited the growth of Klebsiella oxytoca (MIC 64 μg/mL),
Candida albicans and Candida tropicalis (MIC 64-128 μg/mL). Fourteen extracts at a
concentration of 20 μg/mL showed antitumour activities against human breast cancer
and human renal cancer cells, while two isolates showed anti-tumour activities
against human melanoma cancer cells. Six extracts were able to reduce the
proliferation of human peripheral blood mononuclear cells, indicating some degree of
selective toxicity. Four isolates were able to inhibit Leishmania (Leishmania)
amazonensis and one isolate inhibited Trypanosoma cruzi by at least 40% at 20 μg/mL.
The trypanocidal extract obtained from Fusarium sp. [KF611679] culture was subjected
to bioguided fractionation, which revealed beauvericin as the compound responsible
for the observed toxicity of Fusarium sp. to T. cruzi. This depsipeptide showed a
half maximal inhibitory concentration of 1.9 μg/mL (2.43 μM) in a T. cruzi cellular
culture assay.
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Affiliation(s)
- Fernanda Fraga Campos
- Departamento de Ciências Biológicas e da Saúde, Universidade Federal dos Vales do Jequitinhonha e Mucuri, Diamantina, MG, Brasil
| | | | | | | | | | | | - Tânia M A Alves
- Centro de Pesquisas René Rachou-Fiocruz, Belo Horizonte, MG, Brasil
| | | | - Vera Lúcia dos Santos
- Departamento de Microbiologia, Instituto de Ciências Biológicas, Universidade Federal de Minas Gerais, Belo Horizonte, MG, Brasil
| | - Carlos A Rosa
- Departamento de Microbiologia, Instituto de Ciências Biológicas, Universidade Federal de Minas Gerais, Belo Horizonte, MG, Brasil
| | - Carlos L Zani
- Centro de Pesquisas René Rachou-Fiocruz, Belo Horizonte, MG, Brasil
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Nallanchakravarthula S, Mahmood S, Alström S, Finlay RD. Influence of soil type, cultivar and Verticillium dahliae on the structure of the root and rhizosphere soil fungal microbiome of strawberry. PLoS One 2014; 9:e111455. [PMID: 25347069 PMCID: PMC4210224 DOI: 10.1371/journal.pone.0111455] [Citation(s) in RCA: 36] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/10/2014] [Accepted: 10/02/2014] [Indexed: 12/31/2022] Open
Abstract
Sustainable management of crop productivity and health necessitates improved understanding of the ways in which rhizosphere microbial populations interact with each other, with plant roots and their abiotic environment. In this study we examined the effects of different soils and cultivars, and the presence of a soil-borne fungal pathogen, Verticillium dahliae, on the fungal microbiome of the rhizosphere soil and roots of strawberry plants, using high-throughput pyrosequencing. Fungal communities of the roots of two cultivars, Honeoye and Florence, were statistically distinct from those in the rhizosphere soil of the same plants, with little overlap. Roots of plants growing in two contrasting field soils had high relative abundance of Leptodontidium sp. C2 BESC 319 g whereas rhizosphere soil was characterised by high relative abundance of Trichosporon dulcitum or Cryptococcus terreus, depending upon the soil type. Differences between different cultivars were not as clear. Inoculation with the pathogen V. dahliae had a significant influence on community structure, generally decreasing the number of rhizosphere soil- and root-inhabiting fungi. Leptodontidium sp. C2 BESC 319 g was the dominant fungus responding positively to inoculation with V. dahliae. The results suggest that 1) plant roots select microorganisms from the wider rhizosphere pool, 2) that both rhizosphere soil and root inhabiting fungal communities are influenced by V. dahliae and 3) that soil type has a stronger influence on both of these communities than cultivar.
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Affiliation(s)
- Srivathsa Nallanchakravarthula
- Uppsala BioCenter, Department of Forest Mycology and Plant Pathology, Swedish University of Agricultural Sciences, Uppsala, Sweden
- * E-mail:
| | - Shahid Mahmood
- Uppsala BioCenter, Department of Forest Mycology and Plant Pathology, Swedish University of Agricultural Sciences, Uppsala, Sweden
| | - Sadhna Alström
- Uppsala BioCenter, Department of Forest Mycology and Plant Pathology, Swedish University of Agricultural Sciences, Uppsala, Sweden
| | - Roger D. Finlay
- Uppsala BioCenter, Department of Forest Mycology and Plant Pathology, Swedish University of Agricultural Sciences, Uppsala, Sweden
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Dorn-In S, Fahn C, Hölzel CS, Wenz S, Hartwig I, Schwaiger K, Bauer J. Reconstruction of the original mycoflora in pelleted feed by PCR-SSCP and qPCR. FEMS Microbiol Lett 2014; 359:182-92. [PMID: 25088501 DOI: 10.1111/1574-6968.12552] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/12/2014] [Revised: 07/30/2014] [Accepted: 07/30/2014] [Indexed: 11/28/2022] Open
Abstract
Ground feeds for pigs were investigated for fungal contamination before and after pelleting (subsamples in total n = 24) by cultural and molecular biological methods. A fungal-specific primer pair ITS1/ITS5.8R was used to amplify fungal DNA; PCR products were processed for the PCR-SSCP method. In the resulting acrylamide gel, more than 85% of DNA bands of ground feeds were preserved after pelleting. Twenty-two DNA bands were sequenced; all represented fungal DNA. The level of fungal DNA in ground feed samples was equivalent to 4.77-5.69 log10 CFU g(-1) , calculated by qPCR using a standard curve of Aspergillus flavus. In pelleted feed, the level of fungal DNA was in average ± 0.07 log10 different from ground feed. Quantified by cultural methods, the fresh ground feeds contained up to 4.51 log10 CFU g(-1) culturable fungi, while there was < 2.83 log10 CFU g(-1) detected in pelleted feeds. This result shows that, while the process of pelleting reduced the amount of living fungi dramatically, it did not affect the total fungal DNA in feed. Thus, the described methodology was able to reconstruct the fungal microbiota in feeds and reflected a considerable fungal contamination of raw materials such as grains.
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Fungal growth promotor endophytes: a pragmatic approach towards sustainable food and agriculture. Symbiosis 2014. [DOI: 10.1007/s13199-014-0273-3] [Citation(s) in RCA: 37] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
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Yield increase induced by the fungal root endophyte Piriformospora indica in barley grown at low temperature is nutrient limited. Symbiosis 2014. [DOI: 10.1007/s13199-014-0268-0] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
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