Endophytic Fungi (endophytic + fungus)

Distribution by Scientific Domains
Distribution within Life Sciences

Terms modified by Endophytic Fungi

  • endophytic fungus isolated

  • Selected Abstracts


    Are endophytic fungi defensive plant mutualists?

    OIKOS, Issue 1 2002
    Stanley H. Faeth
    Endophytic fungi, especially asexual, systemic endophytes in grasses, are generally viewed as plant mutualists, mainly through the action of mycotoxins, such as alkaloids in infected grasses, which protect the host plant from herbivores. Most of the evidence for the defensive mutualism concept is derived from studies of agronomic grass cultivars, which may be atypical of many endophyte-host interactions. I argue that endophytes in native plants, even asexual, seed-borne ones, rarely act as defensive mutualists. In contrast to domesticated grasses where infection frequencies of highly toxic plants often approach 100%, natural grass populations are usually mosaics of uninfected and infected plants. The latter, however, usually vary enormously in alkaloid levels, from none to levels that may affect herbivores. This variation may result from diverse endophyte and host genotypic combinations that are maintained by changing selective pressures, such as competition, herbivory and abiotic factors. Other processes, such as spatial structuring of host populations and endophytes that act as reproductive parasites of their hosts, may maintain infection levels of seed-borne endophytes in natural populations, without the endophyte acting as a mutualist. [source]


    Antitumor and antifungal activities in endophytic fungi isolated from pharmaceutical plants Taxus mairei, Cephalataxus fortunei and Torreya grandis

    FEMS IMMUNOLOGY & MEDICAL MICROBIOLOGY, Issue 2 2001
    Yaojian Huang
    Abstract The purpose of this work was to screen the endophytic fungi having antitumor or antifungal activity, which were isolated from the inner barks of three kinds of pharmaceutical plants, Taxus mairei, Cephalataxus fortunei and Torreya grandis, collected from Fujian province, China. Antitumor activity was studied by the MTT assay and antifungal activity was determined by observing fungal growth inhibition. 13.4% of endophytic fungi fermentation broths displayed cytotoxic activity on HL-60 cells at and below a dilution of 1:50, and 6.4% on KB cells. 52.3% of endophytic fungi fermentation broths displayed growth inhibition on at least one pathogenic fungi, such as Neurospora sp., Trichoderma sp. and Fusarium sp. Among all endophytic fungi isolated, the genus Paecilomyces sp. has the highest positive rate of antitumor and antifungal activity. These results indicate that endophytic fungi could be a promising source for antitumor and antifungal bioactive agents. [source]


    Fungal endophytes in potato roots studied by traditional isolation and cultivation-independent DNA-based methods

    FEMS MICROBIOLOGY ECOLOGY, Issue 3 2006
    Monika Götz
    Abstract The composition and relative abundance of endophytic fungi in roots of field-grown transgenic T4-lysozyme producing potatoes and the parental line were assessed by classical isolation from root segments and cultivation-independent techniques to test the hypothesis that endophytic fungi are affected by T4-lysozyme. Fungi were isolated from the majority of root segments of both lines and at least 63 morphological groups were obtained with Verticillium dahliae, Cylindrocarpon destructans, Colletotrichum coccodes and Plectosporium tabacinum as the most frequently isolated species. Dominant bands in the fungal fingerprints obtained by denaturing gradient gel electrophoresis analysis of 18S rRNA gene fragments amplified from total community DNA corresponded to the electrophoretic mobility of the 18S rRNA gene fragments of the three most abundant fungal isolates, V. dahliae, C. destructans and Col. coccodes, but not to P. tabacinum. The assignment of the bands to these isolates was confirmed for V. dahliae and Col. coccodes by sequencing of clones. Verticillium dahliae was the most abundant endophytic fungus in the roots of healthy potato plants. Differences in the relative abundance of endophytic fungi colonizing the roots of T4-lysozyme producing potatoes and the parental line could be detected by both methods. [source]


    Endophytic foliar fungi in Betula spp. and their F1 hybrids

    FOREST PATHOLOGY, Issue 4 2003
    K. Saikkonen
    Summary We examined foliar endophyte frequencies in two native (Betula pendula and Betula pubescens) and three exotic (Betula ermanii, Betula platyphylla and Betula resinifera) birch species and their hybrids in Punkaharju, Finland. The most frequently isolated endophytic fungi in the experimental trees were Fusicladium betulae and Gnomonia setacea making up 80,90% of all endophyte infections. Total endophyte infection levels varied from 0.5 colony forming units (CFU)/cm2 in B. platyphylla to 8.6 CFU/cm2 in B. pubescens that had highest total infection levels of both examined endophyte species. The resistance of hybrids was generally very close to the more resistant parent (the only exception being Fusicladium in B. platyphylla × B. pendula hybrid) supporting the hypothesis that the resistance of birch hybrids to these fungi is genetically based and caused by dominant inheritance of resistance traits. Résumé La fréquence d'endophytes foliaires a été étudiée chez deux espèces indigènes de bouleau (Betula pendula et Betula pubescens), trois espèces exotiques (Betula ermanii, Betula platyphylla et Betula resinifera) et leurs hybrides, à Punkaharju, Finlande. Les champignons endophytes les plus fréquemment isolés des arbres étudiés ont étéFusicladium betulae et Gnomonia setacea, qui constituent 80 à 90% de l'ensemble des infections endophytes. Les niveaux totaux d'infection endophyte varient de 0.5 CFU/cm2 chez B. platyphyllaà 8.6 CFU/cm2 chez B. pubescens, qui présente les plus forts niveaux d'infection pour chacune des deux espèces endophytes étudiées. La résistance des hybrides est généralement très proche de celle du parent le plus résistant (la seule exception étant Fusicladium chez l'hybride B. platyphylla × B. pendula), ce qui est conforme à l'hypothèse que la résistance des hybrides à ces champignons serait d'origine génétique, avec une héritabilité dominante de la résistance. Zusammenfassung Bei einheimischen (Betula pendula und Betula pubescens) und drei exotischen (Betula ermanii, Betula platyphylla und Betula resinifera) Birkenarten und ihren Hybriden wurde die Häufigkeit von Blattendophyten in Punkaharju, Finnland, untersucht. Die beiden häufigsten isolierten Pilze waren Fusicladium betulae und Gnomonia setacea. Diese umfassten 80,90% aller isolierten Endophyten. Die Anzahl der aus einem Quadratzentimeter isolierten koloniebildenden Einheiten (CFU/cm2) variierte von 0,5 bei B. platyphylla bis 8,6 CFU/cm2 bei B. pubescens. Letztere hatte die höchste Isolierhäufigkeit bei beiden untersuchten Endophytenarten. Das Resistenzverhalten der Hybriden war allgemein dem des resistenteren Elters sehr ähnlich (eine Ausnahme bildete Fusicladium bei B. platyphylla × B. pendula). Dies stützt die Hypothese, dass die Resistenz der Birkenhybriden gegenüber diesen Pilzen genetisch verankert ist und dominant vererbt wird. [source]


    Colonization of beech leaves by two endophytic fungi in northern Japan

    FOREST PATHOLOGY, Issue 2 2000
    N. Sahashi
    Summary Leaves of Japanese beech (Fagus crenata) were collected monthly during the vegetation period at five sites in the Tohoku district in Japan to isolate endophytic fungi. Leaves were also collected only once at two additional sites. Two endophytic fungi were dominant, a Discula species and a sterile mycelium. This result strongly suggests that these two fungi are generally associated with leaves of the Japanese beech at different sites. At most sites the isolation frequency of Discula sp. was greatest in June and gradually decreased from July to October whereas the isolation frequency of the sterile mycelium increased during the vegetation period and remained at a high isolation frequency in October. Spores of Discula sp. were released for a very short time in late May, just after the disappearance of the snow cover on the forest floor. These spores may be important for the infection of newly sprouting leaves. [source]


    Fungi associated with a natural epizootic in Fiorinia externa Ferris (Hemiptera: Diaspididae) populations

    JOURNAL OF APPLIED ENTOMOLOGY, Issue 2 2009
    J. A. P. Marcelino
    Abstract Stands of eastern hemlock [(Tsuga canadensis (L.) Carrière] in the northeastern United States are in decline, in part from the attack of elongate hemlock scale, Fiorinia externa Ferris (Hemiptera: Diaspididae). From 2001 to the present, a natural epizootic has been observed in populations of F. externa. Initially discovered at the Mianus River Gorge Preserve in Bedford, New York, the epizootic has also been detected in Pennsylvania, New Jersey and Connecticut. Understanding and assessing the identity of the pathogenic micro-organisms responsible for this natural mortality is crucial for developing biological controls for this pest. We have isolated and taxonomically and genetically identified entomopathogens, phytopathogens and endophytic fungi associated with F. externa. Isolates of the following were obtained: Colletotrichum sp., Lecanicillium lecanii, Beauveria bassiana, Metarhiziopsis microspora, Myriangium sp., Mycosphaerella sp. anamorph, Nectria sp., Botrytis sp., Phialophora sp. and Fusarium sp. [source]


    Fungal endophytes from Dioscorea zingiberensis rhizomes and their antibacterial activity

    LETTERS IN APPLIED MICROBIOLOGY, Issue 1 2008
    L. Xu
    Abstract Aims:, The aim of the study was to isolate and characterize the endophytic fungi from the rhizomes of the Chinese traditional medicinal plant Dioscorea zingiberensis and to detect their antibacterial activities. Methods and Results:, After strict sterile sample preparation, nine fungal endophytes were isolated from rhizomes of the Chinese traditional medicinal plant D. zingiberensis. The endophytes were classified by morphological traits and internal transcribed spacer (ITS) rRNA gene sequence analysis. Their ITS rDNA sequences were 99,100% identical to Nectria, Fusarium, Rhizopycnis, Acremonium and Penicillium spp. respectively. Of these, the most frequent genera were Fusarium and Nectria. One isolate, Dzf7, was unclassified on the basis of its low sequence similarity. The next closest species was Alternaria longissima (c. 92·4% sequence similarity). Endophyte isolate Dzf5 showed the closest sequence similarity (c. 99·5%) to an uncultured soil fungus (DQ420800) obtained from Cedar Creek, USA. Bioassays using a modified broth dilution test were used to detect the antibacterial activity of n -butanol extracts of both mycelia and culture filtrates of D. zingiberensis showed biological activity against Bacillus subtilis, Staphylococcus haemolyticus, Escherichia coli and Xanthomonas vesicatoria. Minimal inhibitory concentration (MIC) values of the extracts were between 31·25 ,g ml,1 and 125 ,g ml,1. Conclusions:, Endophytic fungus Dzf2 (c. 99·8% sequence similarity to Fusarium redolens) isolated from D. zingiberensis rhizome showed the most potent antibacterial activities. Significance and Impact of the Study:, Endophytic fungi isolated from D. zingiberensis may be used as potential producers of antibacterial natural products. [source]


    Diversity of endophytic fungi of single Norway spruce needles and their role as pioneer decomposers

    MOLECULAR ECOLOGY, Issue 7 2001
    Michael M. Müller
    Abstract The diversity of endophytic fungi within single symptomless Norway spruce needles is described and their possible role as pioneer decomposers after needle detachment is investigated. The majority (90%) of all 182 isolates from green intact needles were identified as Lophodermium piceae. Up to 34 isolates were obtained from single needles. Generally, all isolates within single needles had distinct randomly amplified microsatellite (RAMS) patterns. Single trees may thus contain a higher number of L. piceae individuals than the number of their needles. To investigate the ability of needle endophytes to act as pioneer decomposers, surface-sterilized needles were incubated on sterile sand inoculated with autoclaved or live spruce forest humus layer. The dry weight loss of 13,17% found in needles after a 20-week incubation did not significantly differ between the sterilized and live treatments. Hence, fungi surviving the surface sterilization of needles can act as pioneer decomposers. A considerable portion of the needles remained green during the incubation. Brown and black needles, in which the weight loss had presumably taken place, were invaded throughout by single haplotypes different from L. piceae. Instead, Tiarasporella parca, a less common needle endophyte, occurred among these invaders of brown needles. Needle endophytes of Norway spruce seem thus to have different abilities to decompose host tissues after needle cast. L. piceae is obviously not an important pioneer decomposer of Norway spruce needles. The diversity of fungal individuals drops sharply when needles start to decompose. Thus, in single needles the decomposing mycota is considerably less diverse than the endophytic mycota. [source]


    Fungal endophytes in a 400-million-yr-old land plant: infection pathways, spatial distribution, and host responses

    NEW PHYTOLOGIST, Issue 3 2007
    Michael Krings
    Summary ,,The Early Devonian Rhynie chert has been critical in documenting early land plant,fungal interactions. However, complex associations involving several fungi that enter into qualitatively different relationships with a single host plant and even interact with one another have not yet been detailed. ,,Here, we studied petrographic thin sections of the Rhynie chert plant Nothia aphylla. ,,Three fungal endophytes (co)occur in prostrate axes of this plant: narrow hyphae producing clusters of small spores; large spherical spores/zoosporangia; and wide aseptate hyphae that form intercellular vesicles in the cortex. Host responses on attack include bulging of infected rhizoids, formation of encasement layers around intracellular hyphae, and separation of infected from uninfected tissues by secondarily thickened cell walls. ,,A complex simultaneous interaction of N. aphylla with three endophytic fungi was discovered. The host responses indicate that some of the mechanisms causing host responses in extant plants were in place 400 million yr ago. Anatomical and life history features of N. aphylla suggest that this plant may have been particularly susceptible to colonization by fungi. [source]


    Antimicrobial and cytotoxic activities of Malaysian endophytes

    PHYTOTHERAPY RESEARCH, Issue 5 2010
    Kalavathy Ramasamy
    Abstract Endophytes, which are receiving increasing attention, have been found to be potential sources of bioactive metabolites following the discovery of paclitaxel producing endophytic fungi. In the present study, a total of 348 endophytes were isolated from different parts of 24 Malaysian medicinal plants. Three selected endophytes (HAB10R12, HAB11R3 and HAB21F25) were investigated for their antimicrobial and cytotoxic activities. For antimicrobial activity, HAB10R12 and HAB11R3 were found to be most active against bacteria and fungi, respectively. Their antimicrobial effects were comparable to, if not better than, a number of current commercial antibacterial and antifungal agents. Both HAB10R12 and HAB21F25 were found to be potential anticancer drug candidates, having potent activity against MCF-7 and HCT116 cell lines and warrant further investigation. Copyright © 2009 John Wiley & Sons, Ltd. [source]


    Calystegines in Calystegia sepium do not Inhibit Fungal Growth and Invertase Activity but Interact with Plant Invertase

    PLANT BIOLOGY, Issue 2 2004
    D. Höke
    Abstract: Calystegines are alkaloidal glycosidase inhibitors. They accumulate predominantly in young and meristemic parts of Calystegia sepium (Convolvulaceae). C. sepium, bindweed, infests meadows and cereal fields and is difficult to control chemically. Fungal pathogens against C. sepium are established as mycoherbicides. Stagonospora convolvuli LA39 attacks C. sepium and does not affect crop plants, but young plants of C. sepium are less susceptible to the fungus. The interaction of Stagonospora convolvuli with calystegines was investigated. Further, endophytic fungi of several classes were isolated from wild-grown Calystegia sepium leaves, and selected strains were tested for interaction with calystegines. Fungal growth on agar containing calystegines was not affected considerably. Plants in climate chambers were infected with an endophyte, Phomopsis, and with the fungal pathogen, Stagonospora convolvuli. Calystegine levels were measured in infected and non-infected plant tissues. Accumulation depended on developmental stage of the plant tissue and was not influenced by infection. Acid invertase was measured from fungal mycelia and from infected and non-infected plant tissues. Fungal acid invertase activity was not inhibited by 10 mM calystegine B2, while invertase from C. sepium leaves was inhibited. It is concluded that calystegines do not inhibit fungal development and sucrose consumption under the conditions of the present investigation, but may act by redirection of plant carbohydrate metabolism. [source]


    Near-term impacts of elevated CO2, nitrogen and fungal endophyte-infection on Lolium perenne L. growth, chemical composition and alkaloid production

    PLANT CELL & ENVIRONMENT, Issue 11 2005
    MATHEW G. HUNT
    ABSTRACT Carbon dioxide has been rapidly accumulating in the atmosphere and is expected to continue to do so. This accumulation is presumed to have important direct effects on plant growth. The interacting affects of a small increase in CO2 concentration (466 p.p.m., approximately 30% increase from current ambient conditions), nitrogen fertilization and fungal endophyte (Neotyphodium lolii) infection on the growth and chemical composition of perennial ryegrass (Lolium perenne) were investigated. It was found that dry mass production was approximately 50% greater under elevated CO2 than under ambient CO2, but only in conditions of high soil N. High molecular weight carbohydrates and total carbohydrates (LMW + HMW CHO) depended on an interaction between CO2 and endophyte infection. Infected plants contained significantly more carbohydrate than endophyte-free plants, and the difference was greatest in ambient CO2 conditions. Protein concentrations were also influenced by the interaction between CO2 and endophyte-infection. Endophyte-free plants had 40% lower concentrations of soluble protein under elevated CO2 than under ambient CO2, but this CO2 effect on soluble protein was largely absent in endophyte-infected plants. CO2, endophyte-infection and nitrogen interacted to influence the total chlorophyll concentration of the grass such that chlorophyll concentration was always lower in elevated CO2 but this decline was much greater in endophyte-free plants, particularly in conditions of high soil N. In the endophyte-infected plants, the concentrations of the pyrrolopyrazine alkaloid peramine depended on the interaction between CO2 and N fertilization such that peramine concentrations declined with increasing N at ambient CO2 but remained roughly constant across N levels at elevated CO2. A similar pattern was seen for the ergot alkaloid ergovaline. The biochemical responses of perennial ryegrass to elevated CO2 are clearly modified by the presence of endophytic fungi. [source]


    Dynamics of Neotyphodium endophyte infection in ageing seed pools: incidence of differential viability loss of endophyte, infected seed and non-infected seed

    ANNALS OF APPLIED BIOLOGY, Issue 2 2010
    P.E. Gundel
    Symbiotic associations between grasses and vertically transmitted endophytic fungi are widespread in nature. Within grass populations, changes in the frequency of infected plants are driven by influence of the endophyte on the fitness of their hosts and by the efficiency of endophyte transmission from parent plants to their offspring. During the seed stage, the endophyte might influence the fitness of its host by affecting the rate of seed viability loss, whereas the efficiency of endophyte transmission is affected by losses of viability of the fungus within viable seeds. We assessed the viability losses of Lolium multiflorum seeds with high and low level of infection of the endophyte Neotyphodium occultans, as well as the loss of viability of the fungus itself, under accelerated seed ageing and under field conditions. Starting with high endophyte-infected accessions of L. multiflorum, we produced their low endophyte-infected counterparts by treating seeds with a fungicide, and subsequently multiplying seeds in adjacent plots allowing pollen exchange. In our accelerated ageing experiments, which included three accessions, high endophyte-infected seeds lost viability significantly faster than their low endophyte-infected counterpart, for only one accession. High endophyte-infected seeds of this particular accession absorbed more water than low endophyte-infected seeds. In contrast, the endophyte lost viability within live seeds of all three accessions, as the proportions of viable seeds producing infected seedlings decreased over time. In our field experiment, which included only one accession, high endophyte-infected seed lost viability significantly but only slightly faster than low endophyte-infected seed. In contrast, the loss of viability of the endophyte was substantial as the proportions of viable seeds producing infected seedlings decreased greatly over time. Moving the seeds from the air to the soil surface (simulating seed dispersion off the spikes) decreased substantially the rate of seed viability loss, but increased the rate of endophyte viability loss. Our experiments suggest that, in ageing seed pools, endophyte viability loss and differential seed mortality determine decreases in the proportions of endophyte-infected seeds in L. multiflorum. Endophyte viability loss within live seeds contributes substantially more to infection frequency changes than differential viability losses of infected and non-infected seeds. [source]


    Colonisation of barley roots by endophytic Fusarium equiseti and Pochonia chlamydosporia: Effects on plant growth and disease

    ANNALS OF APPLIED BIOLOGY, Issue 3 2009
    J.G. Maciá-Vicente
    Abstract Colonisation of plant roots by endophytic fungi may confer benefits to the host such as protection against abiotic or biotic stresses or plant growth promotion. The exploitation of these properties is of great relevance at an applied level, either to increase yields of agricultural crops or in reforestation activities. Fusarium equiseti is a naturally occurring endophyte in vegetation under stress in Mediterranean ecosystems. Pochonia chlamydosporia is a nematode egg-parasitic fungus with a worldwide distribution. Both fungi have the capacity to colonise roots of non-host plants endophytically and to protect them against phytopathogenic fungi under laboratory conditions. The aim of this study was to evaluate the root population dynamics of these fungi under non-axenic practical conditions. Both fungal species were inoculated into barley roots. Their presence in roots and effects on plant growth and incidence of disease caused by the pathogen Gaeumannomyces graminis var. tritici were monitored periodically. Both fungi colonised barley roots endophytically over the duration of the experiment and competed with other existing fungal root colonisers. Furthermore, colonisation of roots by P. chlamydosporia promoted plant growth. Although a clear suppressive effect on disease could not be detected, F. equiseti isolates reduced the mean root lesion length caused by the pathogen. Results of this work suggest that both F. equiseti and P. chlamydosporia are long-term root endophytes that confer beneficial effects to the host plant. [source]


    Fungal community diversity and soil health in intensive potato cropping systems of the east Po valley, northern Italy

    ANNALS OF APPLIED BIOLOGY, Issue 2 2009
    L.M. Manici
    Abstract An ecological approach was used to investigate the relationship between diversity of soil fungal communities and soil-borne pathogen inoculum in a potato growing area of northern Italy affected by yield decline. The study was performed in 14 sites with the same tillage management practices: 10 named ,potato sites', that for many years had been intensely cultivated with potatoes, and 4 named ,rotation sites', subject to a 4-year rotation without potatoes or any recurrent crop for many years. Fungal communities were recorded using conventional (soil fungi by plate count and endophytic fungi as infection frequency on pot-grown potato plant roots in soil samples) and molecular approaches [Basidiomycetes and Ascomycetes with specific and denaturing gradient gel electrophoresis (DGGE) analysis]. Diversity of fungal communities in potato sites was significantly lower than that in rotation sites. In addition, fungal communities in rotation sites showed lower Berger,Parker dominance than those in the potato sites, suggesting that rotation sites had a higher diversity as well as a better fungal community balance than potato sites. The ANalysis Of SIMilarity test of soil fungi and root endophytic fungi revealed that the two cropping systems differed significantly for species composition. Root endophytic fungal communities showed a greater ability to colonise potato roots in soil samples from potato sites than those from rotation sites. Moreover, the majority of endophytic root fungal community species in potato sites belonged to the potato root rot complex and storage disease (Colletotrichum coccodes, Fusarium solani and Fusarium oxysporum), while those in rotation sites were mainly ubiquitous or saprobic fungi. Soil rDNA analyses showed that Ascomycetes were much more frequent than Basidiomycetes in all the soils examined. DGGE analysis, with the Ascomycete-specific primer (ITS1F/ITS4A), did not reveal distinctions between the communities found at the potato and rotation sites, although the same analysis showed differences between the communities of Basidiomycetes (specific primer ITS1F/ITS4B). These findings showed that recurrent potato cropping affected diversity and composition of soil fungal communities and induced a shift in specialisation of the endophytic fungi towards potato. [source]


    Rice root colonisation by mycorrhizal and endophytic fungi in aerobic soil

    ANNALS OF APPLIED BIOLOGY, Issue 2 2009
    M. Vallino
    Abstract Arbuscular mycorrhizal (AM) fungi are ubiquitous root symbionts that form intimate associations with the majority of plants growing in aerobic soil; fungal endophytes live internally, either intercellularly or intracellularly, and asymptomatically within plant tissues. Their presence is correlated with an increased response to biotic and abiotic stress. The populations of AM and of endophytic fungi were studied in the roots of different rice varieties grown in aerobic condition, in experimental fields in Vercelli, North Italy. All the rice varieties resulted colonised by AM fungi with a percentage of arbuscularisation ranging between 4% and 28%. Preliminary molecular analyses on some rice varieties showed that the AM population was composed of fungi identified as Glomus intraradices, on the basis of 18S ribosomal gene. All the varieties analysed but one resulted in colonisation by endophytic fungi. About 300 fungal isolates were obtained, belonging mainly to the genera Neotyphodium, Stagonospora and Penicillium. [source]


    Transfer of endophyte-origin defensive alkaloids from a grass to a hemiparasitic plant

    ECOLOGY LETTERS, Issue 12 2005
    Päivi Lehtonen
    Abstract Plants growing in natural environments experience myriad interactions with a diverse assemblage of pathogens, parasites and mutualists. Many of these interactions involve symbiotic bacteria and fungi, but they also include macroparasitic plants. In this study, we investigated the interactions among a host grass (Lolium pratense, ex., Festuca pratensis), its symbiotic endophytic fungus (Neotyphodium uncinatum), a root hemiparasitic plant (Rhinanthus serotinus) of the host grass and a generalist herbivore (aphid Aulacorthum solani) of the hemiparasite. We demonstrate that the hemiparasitic plant acquires defending mycotoxins produced by the endophytic fungus living within their shared host grass. The uptake of defensive mycotoxins from the endophyte-infected host grass enhances the resistance of the hemiparasitic plant to the generalist aphid herbivore. Endophyte infection increases the performance of the hemiparasitic plant, but reduces the growth of the host grass. In other words, the mutualistic endophytic fungus becomes parasitic in the presence of the hemiparasitic plant. Our results suggest that the outcomes of grass,endophyte interactions are conditional on the complexity of community-level interactions; thus, the outcome of multispecies interactions may not be predictable from pair-wise combinations of species. [source]


    Fungal endophytes in potato roots studied by traditional isolation and cultivation-independent DNA-based methods

    FEMS MICROBIOLOGY ECOLOGY, Issue 3 2006
    Monika Götz
    Abstract The composition and relative abundance of endophytic fungi in roots of field-grown transgenic T4-lysozyme producing potatoes and the parental line were assessed by classical isolation from root segments and cultivation-independent techniques to test the hypothesis that endophytic fungi are affected by T4-lysozyme. Fungi were isolated from the majority of root segments of both lines and at least 63 morphological groups were obtained with Verticillium dahliae, Cylindrocarpon destructans, Colletotrichum coccodes and Plectosporium tabacinum as the most frequently isolated species. Dominant bands in the fungal fingerprints obtained by denaturing gradient gel electrophoresis analysis of 18S rRNA gene fragments amplified from total community DNA corresponded to the electrophoretic mobility of the 18S rRNA gene fragments of the three most abundant fungal isolates, V. dahliae, C. destructans and Col. coccodes, but not to P. tabacinum. The assignment of the bands to these isolates was confirmed for V. dahliae and Col. coccodes by sequencing of clones. Verticillium dahliae was the most abundant endophytic fungus in the roots of healthy potato plants. Differences in the relative abundance of endophytic fungi colonizing the roots of T4-lysozyme producing potatoes and the parental line could be detected by both methods. [source]


    Benzodiazepine Alkaloids from Marine-Derived Endophytic Fungus Aspergillus ochraceus

    HELVETICA CHIMICA ACTA, Issue 7 2009
    Chuan-Ming Cui
    Abstract A new fungus-derived benzodiazepine analogue, 2-hydroxycircumdatin C (1), and a compound which has been isolated from a natural resource for the first time, but has been previously synthesized, namely (11aS)-2,3-dihydro-7-methoxy-1H -pyrrolo[2,1- c][1,4]benzodiazepine-5,11(10H,11aH)-dione (2), along with five structurally related known alkaloids (3,7), were isolated from Aspergillus ochraceus, an endophytic fungus derived from the marine brown alga Sargassum kjellmanianum. Their structures were established on the basis of spectroscopic methods. The absolute configuration of 1 was determined through CD evidence. Compound 1 displayed significant DPPH radical-scavenging activity with an IC50 value of 9.9,,M, which is 8.9-fold more potent than that of butylated hydroxytoluene (BHT), a well-known synthetic positive control. [source]


    A new spiroketal from Aspergillus terreus, an endophytic fungus in Opuntia ficusindica Mill

    JOURNAL OF BASIC MICROBIOLOGY, Issue 2 2008
    Shao-Hua Wu
    Abstract A new spiroketal, named aspergiketal (1) was isolated from the culture broth of Aspergillus terreus, an endophytic fungus in the stems of the plant Opuntia ficusindica Mill., together with two known compounds, physcion (2) and asterric acid (3). Their structures were elucidated by spectroscopic methods including 2D-NMR techniques. (© 2008 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim) [source]


    1H and 13C NMR signal assignments of Paecilin A and B, two new chromone derivatives from mangrove endophytic fungus Paecilomyces sp. (tree 1,7)

    MAGNETIC RESONANCE IN CHEMISTRY, Issue 9 2007
    Zhiyong Guo
    Abstract Two new natural products, named paecilin A (1) and B (2), together with two known compounds secalonic acid D (3) and (11)-cytochalasa-6(12),13-diene-1,21-dione-16,18-dimethyl-7-hydroxy-l0-phenyl-(7S*,13E,16S*,18S*) (4), were isolated from the mangrove endophytic fungus, Paecilomyces sp. (tree 1,7) from the South China Sea. 1D and 2D NMR experiments including COSY, HMQC, and HMBC were used for the determination of their structures. In our cytotoxicity assays, secalonic D (3) showed cytotoxicity toward KB cells with IC50 < 1 µg ml,1 and inhibiting human topoisomerase I with IC50 at 0.16 µmol ml,1. 1, 2, and 4 showed no activity to KB cells. Copyright © 2007 John Wiley & Sons, Ltd. [source]