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1

Boland, Holly Terry. "Grazing Behavior of Beef Steers Grazing Endophyte-Infected, Endophyte-Free, and Novel Endophyte Infected Tall Fescue, and Lakota Prairie Grass." Thesis, Virginia Tech, 2005. http://hdl.handle.net/10919/34557.

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Endophyte infected Tall fescue (Festuca arundinacea Schreb.) is the most dominant grass used for pasture in the Southeastern U.S. As a result, fescue toxicosis is a major concern. Producers need alternative forages for grazing cattle that do not have this negative aspect. The objective of this experiment was to determine the grazing behavior of cattle grazing Lakota (L) prairie grass (Bromus catharticus Vahl.), endophyte infected (E+), endophyte free (E-), and novel endophyte (Q) tall fescues. Angus-crossbred steers (279±8 kg) steers wore electronic behavior data recorders in four sampling p
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Holmes, Amanda Christine. "Host-endophyte interactions in Zantedeschia aethiopica." Thesis, University of the West of England, Bristol, 1997. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.389513.

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3

Reivant, Munters Arielle. "The foliar bacterial endophyte community in native Pinus radiata: a role for protection against fungal disease?" Thesis, Uppsala universitet, Institutionen för biologisk grundutbildning, 2014. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-234871.

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Pinus radiata is the most planted tree in the southern hemisphere. The planted trees are especially susceptible to pathogens, but even the native population, nowadays limited tomerely five locations, are threatened by diseases caused by arthropods, fungi and dehydration. Endophytes are bacteria or fungi that reside inside healthy plant tissue, and often have a beneficial effect on their hosts. Endophytes can help plants adapt to abiotic stress such as drought and protect them against pathogens and insect pests. Given the roles that endophytes play in host stress responses, it is possible that
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Al-Nahidh, S. I. "Host-endophyte compatibility in mycorrhizal crop plants." Thesis, University of Leeds, 1985. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.354035.

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5

King, Eoghan. "Caractérisation phénotypique et moléculaire de la réponse du riz au cours de l’interaction avec des espèces de Burkholderia s.l." Thesis, Montpellier, 2019. http://www.theses.fr/2019MONTG079.

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Dans les conditions naturelles, les plantes interagissent avec une grande diversité de microorganismes, entretenant avec elles des types d’interactions variées allant du mutualisme à la pathogénie. Quelque soit le type d’interaction mis en place, les plantes sont capables de reconnaitre des motifs moléculaires microbiens conservés qui induisent l’activation d’une réponse immunitaire dite « non-hôte ». Cette réponse immunitaire basale a largement été étudiée dans le cas des interactions avec des microorganismes mutualistes et pathogènes. Cependant, dans le cas des « symbioses associatives » ave
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Barenstrauch, Margot. "Characterization of oxylipin signaling in the chemical interaction between the endophyte Paraconiothyrium variabile and the phytopathogen Fusarium oxysporum." Thesis, Paris, Muséum national d'histoire naturelle, 2018. http://www.theses.fr/2018MNHN0010/document.

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Les champignons endophytes sont des microorganismes non-pathogènes impliqués dans des associations mutualistes avec les plantes. Les endophytes foliaires, en particulier, représentent un groupe très divers, mais leurs interactions avec la plante hôte et ses micro-organismes associés sont peu connues. Des travaux préliminaires initiés par notre équipe, explorant la diversité microbienne foliaire du conifère Cephalotaxus harringtonia, ont permis d’isoler la souche fongique Paraconiothyrium variabile (Ascomycota), un antagoniste du phytopathogène Fusarium oxysporum. Au cours de leur interaction,
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Athman, Shahasi Yusuf. "Host-endophyte-pest interactions of endophytic Fusarium oxysporum antagonistic to Radopholus similis in banana (Musa spp.)." Thesis, Pretoria : [s.n.], 2006. http://upetd.up.ac.za/thesis/available/etd-12072006-105803.

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8

Wäli, P. (Piippa). "Environment and genetic background affecting endophyte-grass symbiosis." Doctoral thesis, University of Oulu, 2006. http://urn.fi/urn:isbn:9514281632.

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Abstract Mutualism is often conditional and the associations vary from antagonism to mutualism along environmental conditions and genotypes of interacting species. I studied antagonism-mutualism continuum hypothesis of symbiosis experimentally using two different Epichloë/Neotyphodium endophytes and their host grasses, agricultural meadow fescues and natural fine fescue, as study systems. These systemic fungal endophytes live asymptomatically within aerial tissues of grasses, and are vertically transmitted to the next grass generation via seeds. Thus, asexual endophyte strains are dependent on
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9

Babu, Jacob. "Bioactive Chemicals of Importance in Endophyte-Infected Grasses." The University of Waikato, 2009. http://hdl.handle.net/10289/2608.

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Janthitrems are believed to be involved in the observed sporadic cases of AR37- infected perennial ryegrass staggers. Investigations into the role of janthitrems in perennial ryegrass staggers are difficult as isolation of the compounds from the ryegrass is hindered by the inherent instability of these compounds. Therefore attempts were made to isolate janthitrems from an alternative source, allowing these janthitrem analogues to be used as surrogates for endophyte produced janthitrems. Analysis of a series of Penicillium janthinellum cultures revealed the presence of janthitrems in a number o
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10

Craven, Kelly D. "COEVOLUTION AND GENETIC DIVERSITY IN GRASS-ENDOPHYTE SYMBIOSES." UKnowledge, 2003. http://uknowledge.uky.edu/gradschool_diss/431.

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Symbioses between cool-season grasses (Subfamily Pooideae) and endophytic fungi in the genera Epichlo and Neotyphodium straddle a continuum of interactions from antagonistic to highly mutualistic. Although these two genera of endophytes are closely related, Neotyphodium endophytes are strictly seed-transmitted and provide many physiological and defensive benefits to their hosts, while Epichlo spp. have an obligately sexual contagious stage wherein host inflorescences are replaced by fungal sexual structures (stromata), effectively sterilizing the plant. Between these two extremes of interactio
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11

Bailes, Graham. "Drivers of endophyte communities in Pacific Northwest prairies." Thesis, University of Oregon, 2017. http://hdl.handle.net/1794/22783.

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Prairies of the Pacific Northwest are threatened systems, with only ~2% of historic land remaining. The combined risk of global climate change and land use change make these systems a high conservation priority. However, little attention has been paid to the microbiota. Fungal endophytes are ubiquitous in plants and are important in ecosystem functioning and host dynamics. To understand fungal community assembly, we used high-throughput sequencing to investigate the composition of fungal foliar endophyte communities in two native, cool-season (C3) bunchgrasses along a natural latitudinal g
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12

Barakat, Fatima. "Etude mycochimique et activités leishmanicides de composés issus de Botryosphaeria mamane, un champignon endophyte isolé de Bixa orellana L." Thesis, Toulouse 3, 2018. http://www.theses.fr/2018TOU30227.

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Les maladies tropicales négligées, telle que la leishmaniose, constituent un problème majeur de santé publique, en particulier dans les pays à faible revenu où cette maladie sévit. Le nombre limité des médicaments disponibles, leurs coûts, leurs effets indésirables et l’émergence de résistances, exige la recherche de nouveaux agents thérapeutiques. Les champignons endophytes constituent une source prometteuse de nouvelles molécules bioactives. Dans ce contexte, une étude mycochimique a été menée sur une souche endophyte de Botryosphaeria mamane, un micromycète relativement peu étudié, isolée d
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Grünig, Christoph. "Population biology of the tree-root endophyte Phialocephala fortinii /." [Zürich], 2003. http://e-collection.ethbib.ethz.ch/show?type=diss&nr=15313.

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14

Hunt, Matthew. "Effects of environmental change on endophyte-plant-insect relationships." Thesis, University of Oxford, 2003. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.275301.

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15

Triastuti, Asih. "Exploration de la diversité chimique dans les endophytes fongiques : influence de l'addition des modificateurs épigénétiques et des co-cultures fongiques sur le métabolome de Botryosphaeria mamane." Thesis, Toulouse 3, 2018. http://www.theses.fr/2018TOU30228.

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Ce travail porte sur l'étude chimique d'une souche endophyte de Botryosphaeria mamane, un micromycète relativement peu étudié, isolée des feuilles de Bixa orellana. Des travaux préliminaires portant sur le screening de 409 souches de champignons isolés à partir de plantes médicinales d'Amérique du Sud a révélé que parmi celles-ci, B. mamane E224 était l'une des souches les plus actives in vitro sur un modèle de Leishmania infantum. L'objectif de ce travail a consisté en l'induction de la production de nouveaux métabolites secondaires produits par B. mamane via l'optimisation des conditions de
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16

Oliver, Katherine Rene. "Consumption of Endophyte Infected Fescue During Gestation in Beef Cows." Thesis, Virginia Tech, 2016. http://hdl.handle.net/10919/81478.

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Tall fescue is a widely grown, cool season grass prevalent in the eastern United States that is known for its resistance to abiotic and biotic stresses. A main reason for tall fescue's resistance to these stresses is attributed to the presence of a fungal endophyte. Unfortunately, this endophyte also adversely affects cattle production. Cows consuming the ergot alkaloids produced by these endophytes can exhibit decreased feed intake, growth performance, organ vasoconstriction, and increased rectal temperature. This work is interested in examining how endophyte toxin exposure impacts pregnanc
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17

Owens, Herbert Troye III. "BEEF CATTLE GRAZING PREFERENCE OF TALL FESCUE AS AFFECTED BY ENDOPHYTE." UKnowledge, 2011. http://uknowledge.uky.edu/gradschool_theses/88.

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Many factors control, contribute to, stimulate and limit forage selection. It is apparent that cattle prefer certain cultivars compared to others. This study sought to test if cattle displayed preferences for certain cultivars over a two-year period in 2008 and 2009. Determining the effect of endophyte status on preference was another objective. Previous research showed rapid increase in the selection of preferred cultivars, i.e., diet learning. We attempted to replicate those results. Forty cultivars (34 tall fescue (Lolium arundinaceum (Schreb.) Darbysh.) cultivars), two festuloliums (Festuc
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Rickly, Zinner Rachel Ann. "ADAPTATION OF LAMBS TO AN ENDOPHYTE INFECTED TALL FESCUE SEED DIET." UKnowledge, 2011. http://uknowledge.uky.edu/animalsci_etds/3.

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Ten wether lambs were used to determine the effects of ergovaline consumption from endophyte infected tall fescue, on nutrient utilization and metabolism. Lambs were fed a diet of 23% endophyte free tall fescue seed (E-) and 77% concentrate from d -14 to -1 (adaptation phase). On d 0, five lambs were switched to an endophyte infected seed diet (E+) where they remained through d 14. Nutrient digestibilities tended to increase from adaptation through the acute (d 1 to 4) to subacute (d 10 to 14) phases when E- was fed. E+ digestibilities were highest (P < 0.05) in the acute phase. Lambs fed E+ h
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Bagherzadeh, Mahtaab. "CAN INCREASING GRASS-FUNGAL ENDOPHYTE SYMBIOTIC DIVERSITY ENHANCE GRASSLAND ECOSYSTEM FUNCTIONING?" UKnowledge, 2018. https://uknowledge.uky.edu/pss_etds/105.

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The relationship between biodiversity and ecosystem functioning is important in maintaining agroecosystem sustainability. Plant-microbe symbioses, such as exists between the grass tall fescue (Schedonorus arundinaceum) and the asexual fungal endophyte Epichloë coenophiala, can be utilized to enhance agroecosystem functions, such as herbivore resistance. “Novel” E. coenophiala strains that vary in the production of mammal- and insect-toxic compounds have been identified, inserted into tall fescue cultivars, and are planted in pastures globally. Novel fungal endophyte-tall fescue associations ma
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20

O'Callaghan, Kenneth John. "Interactions of rhizobia with Sesbania rostrata, wheat and oilseed rape : a comparative study." Thesis, University of Nottingham, 1999. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.285558.

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21

Brosi, Glade Blythe. "THE RESPONSE OF TALL FESCUE AND ITS FUNGAL ENDOPHYTE TO CLIMATE CHANGE." UKnowledge, 2011. http://uknowledge.uky.edu/gradschool_theses/126.

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Tall fescue is the most common cool-season grass in the eastern USA, with broad economic and ecological importance to the region. Tall fescue is known to associate with a fungal endophyte, Neotyphodium coenophialum, whose presence can decrease biotic and abiotic stress experienced by the plant. This thesis evaluates the response of tall fescue and the fungal endophyte symbiosis to predicted climate change. I participated in two multi-factor climate change projects where I investigated the response of tall fescue tissue chemistry and growth to various climate change factors. Endophyte-infected
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22

Bourguignon, Marie. "Ecophysiological Responses of Tall Fescue Genotypes to Endophyte Infection and Climate Change." UKnowledge, 2013. http://uknowledge.uky.edu/pss_etds/28.

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Tall fescue is a widely used forage grass in the eastern USA and can form a symbiosis with a fungal endophyte, which can be beneficial for the plant but can cause livestock health issues. Little is known regarding the symbiotic response to predicted climate change. To address this knowledge gap, I analyzed tall fescue variety trial data collected throughout the U.S., exploring relationships between climate variables and yield for two different fescue cultivars that were either endophyte-free or infected. This study showed no endophyte or cultivar effect on fescue yield, but identified temperat
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Ben, Chobba Kadri Inès. "Élaboration et mise en oeuvre d'une approche de caractérisation systémique d'un agent étiologique émergent à fort impact économique et de moyens de lutte biologique : application à la maladie de la feuille cassante du palmier dattier (Phoenix dactylifera L.)." Thesis, Montpellier 2, 2013. http://www.theses.fr/2013MON20077.

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La Maladie de la Feuille Cassante du Palmier dattier (Phoenix dactylifera L.) constitue un cas d'émergence d'une maladie à fort impact économique causée par un agent étiologique inconnu. Notre stratégie a visé à élaborer une approche sans à priori de l'émergence pouvant être transposée à n'importe quelle situation de ce type. En nous appuyant sur des caractérisations successives des compartiments viraux, bactériens et fongiques de tissus sains et malades, nous avons cherché à mettre en évidence des différences de composition spécifiques et de distribution de ces flores sur 2 campagnes de prélè
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Weedon, C. M. "Biosynthesis of indole-diterpenoids and other isoprenoids by the ryegrass endophyte, Acremonium loliae." Thesis, Imperial College London, 1988. http://hdl.handle.net/10044/1/47298.

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25

Ndoye, Idrissa. "Isolement et approche synthétique de produits naturels issus du champignon endophyte Paraconiothyrium variabile." Paris 6, 2012. http://www.theses.fr/2012PA066314.

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Paraconiothyrium variabile est un champignon endophyte isolé du conifère Cephalotaxus harringtonia et a révélé un antagonisme significatif contre des phytopathogènes communs. Nous avons entrepris la caractérisation chimique des métabolites fongiques impliqués dans la relation mutualiste entre cette plante hôte et le champignon endophyte afin d'étudier leur rôle éventuel dans cet antagonisme. Le fractionnement de l'extrait AcOEt du filtrat de culture de P. Variabile a révélé quatre principales familles de métabolites : α-tétralones, isocoumarines, isobenzofuranes et cyclodipeptides dans des con
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Vazquez, Ana M. "Possible Drivers in Endophyte Diversity and Transmission in the Tomato Plant Bacterial Microbiome." The Ohio State University, 2020. http://rave.ohiolink.edu/etdc/view?acc_num=osu1594918263597025.

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27

Huang, Yu-Ling, and Yu-Ling Huang. "An Integrative Study of Endophyte Symbioses: Environmental Change, Evolutionary Dynamics, and Leaf Colonization." Diss., The University of Arizona, 2017. http://hdl.handle.net/10150/625616.

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Fungi have evolved to encompass a diversity of strategies that collectively allow them to occupy the majority of earth’s ecosystems. Among these, endophytism is one of the most widespread and yet least well understood. Endophytes are fungi that live in plants without causing disease. These fungal symbionts are highly diverse and have been found in plants from tropical forests to hot deserts and arctic tundra. Even though endophytes are globally distributed as a whole, it is clear that environmental factors, interactions with potential hosts, and a variety of evolutionary processes together det
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Al-Busaidi, Harith N. K. "Secondary metabolites from Xylaria endophytes : the isolation and structure elucidation of secondary metabolites from Xylaria endophytes by chemical and spectroscopic methods." Thesis, University of Bradford, 2011. http://hdl.handle.net/10454/5266.

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CONCAS, JONATHAN. "Spatial Distribution of Grapevine Esca Disease in Vineyards of the Marche Region and Study of Fungal Endophytic Communities." Doctoral thesis, Università Politecnica delle Marche, 2019. http://hdl.handle.net/11566/263846.

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Il mal dell’esca è una malattia complessa, determinata da diversi agenti fungini, che ha attualmente un importante impatto economico sulla viticoltura mondiale. I principali obiettivi della ricerca sono stati i) l’analisi spaziale delle viti con sintomi di mal dell’esca e ii) lo studio delle comunità fungine in viti sintomatiche e asintomatiche. Per quanto riguarda il primo obiettivo, è stato condotto uno studio sulla diffusione del mal dell’esca in tre vigneti commerciali nelle Marche, in modo da poter comprendere meglio come l’infezione evolve nel tempo e nello spazio. Dall’elaborazione dei
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Blankenship, Jimmy Douglas. "LOLINE ALKALOID BIOSYNTHESIS IN NEOTYPHODIUM UNCINATUM, A FUNGAL ENDOPHYTE OF LOLIUM PRATENSE." Lexington, Ky. : [University of Kentucky Libraries], 2004. http://lib.uky.edu/ETD/ukyplpa2004d00157/JDB2004.pdf.

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Thesis (Ph. D.)--University of Kentucky, 2004.<br>Title from document title page (viewed Sept. 14, 2004). Document formatted into pages; contains ix, 97 p. : ill. Includes abstract and vita. Includes bibliographical references (p. 86-96).
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Nebert, Lucas. "On Germs and Germination: Uncovering the Hidden Ecology of Seedborne Bacteria and Fungi in Open-Pollinated Maize." Thesis, University of Oregon, 2018. http://hdl.handle.net/1794/23909.

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Plants are inhabited by diverse species of bacteria and fungi, which affect plant health and fitness. Endophytes are bacteria or fungi that live within plant host tissues without causing symptoms of disease, and mediate important plant traits in agriculture, such as nutrient acquisition, disease resistance, and abiotic stress tolerance. However, we know little about the general ecology of endophytes, including which factors determine their compositions within plants. Seedborne transmission may represent an important source of bacterial and fungal endophytes, which can significantly impact the
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Al-Busaidi, Harith. "Secondary Metabolites from Xylaria Endophytes: The isolation and structure elucidation of secondary metabolites from Xylaria endophytes by chemical and spectroscopic methods." Thesis, University of Bradford, 2011. http://hdl.handle.net/10454/17479.

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This thesis describes the isolation and structure elucidation of secondary metabolites from a number of endophytic Xylaria fungi. Six Xylaria endophytes were surface cultured on an aqueous malt extract-glucose medium. The fungus A311R, from a palm tree in Thailand, produced nonane-1,2,3-tricarboxylic acid, which was isolated for the first time as a natural product. Also isolated from the same fungus was spiculisporic acid; the first instance of isolation from a Xylaria fungus. The fungus 6RD12 produced cycloepoxydon, which was isolated for the first time from a Xylaria fungus, and 4,5,6-trihyd
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Johnson, Jennifer Michelle. "GRAZING EVALUATION OF A NOVEL ENDOPHYTE TALL FESCUE DEVELOPED FOR THE UPPER TRANSITION ZONE." UKnowledge, 2010. http://uknowledge.uky.edu/gradschool_diss/111.

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A wild-type endophyte (Neotyphodium coenophialum [(Morgan-Jones & Gams) Glen Bacon & Hanlin]) that infects tall fescue [Lolium arundinaceum (Schreb.) Darbysh. = Schedonorous arundinaceum (Schreb.) Dumort.] imparts tolerances to moisture, heat, and grazing stresses, but also produces ergot alkaloids that adversely affect performance and physiology of cattle. Novel endophytes, developed by AgResearch Ltd. NZ, can sustain fescue persistence and productivity, but do not produce toxic ergot alkaloids. University of Kentucky Plant Breeder, T. D. Phillips Ph.D, developed a tall fescue experimental po
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Bussard, Jessica R. "Evaluation of vascular changes in cattle relative to time-off endophyte-infected tall fescue." UKnowledge, 2012. http://uknowledge.uky.edu/pss_etds/7.

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Twenty-four steers were grazed on endophyte (Neotyphodium coenophialum)-infected [[Lolium arundinaceum (Schreb.) Darbysh]; E+] tall fescue (TF) and exposed to ergot alkaloids for an 106-d grazing period. Cattle were removed from pasture, placed in dry lots, and fed a non-toxic diet to evaluate changes in vascular contraction relative to time-off E+ TF pasture. Lateral saphenous veins (SV) were biopsied from steers at 0-, 21-, 42-, and 63-d off TF pasture and from 6 control steers at 0- and 63-d off bermudagrass (BG) pasture. To evaluate contractile response, biopsied SV were exposed to increas
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ZHANG, DONG-XIU. "LOLINE ALKALOID BIOSYNTHESIS GENE EXPRESSION IN EPICHLOE ENDOPHYTES OF GRASSES." UKnowledge, 2008. http://uknowledge.uky.edu/gradschool_diss/592.

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Loline alkaloids (LA) are secondary metabolites produced by Epichloandamp;euml; (anamorph, Neotyphodium) grass endophytes. They are toxic and deterrent to a broad range of herbivorous insects but not to livestock. This protective bioactivity has spurred considerable research into the LA biosynthetic pathway. LOL, the gene cluster containing nine genes, is required for LA biosynthesis. The regulation of LOL genes during LA production in culture and in symbio is of interest. In this study, coordinate regulation between LOL gene expression and LA production level was investigated in both MM cultu
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Arriola, Apelo Sebastian I. "Influence of forage characteristics on grazing behavior of weaned steers." Thesis, Virginia Tech, 2009. http://hdl.handle.net/10919/33311.

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For Virginia, the primary forage base is endophyte-infected tall fescue (Schedonorus phoenix (Scop.) Holub). However, the decreased animal performance and disorders caused by the presence of the fungal endophyte Neotyphodium coenophialum reduces its suitability for many forage-livestock producers. The endophyte, which is found in the inter-cellular space of tall fescue tissues, forms a mutalistic relationship with the plant and helps the fescue tolerate drought, insect predation, and grazing pressure. The production of toxic ergot alkaloids by the endophyte is associated with decreased perfo
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Hoffman, Michele Therese. "Bacterial Endosymbionts of Endophytic Fungi: Diversity, Phylogenetic Structure, and Biotic Interactions." Diss., The University of Arizona, 2010. http://hdl.handle.net/10150/196079.

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This dissertation comprises a series of studies designed to explore the associations between plants and the endophytic fungi they harbor in their above-ground tissues. By viewing endophyte diversity in ecologically and economically important hosts through the lenses of phylogenetic biology, microbiology, and biotechnology, this body of work links plant ecology with newly discovered symbiotic units comprised of endophytic fungi and the bacteria that inhabit them.This work begins with a large-scale survey of endophytic fungi from native and non-native Cupressaceae in Arizona and North Carolina.
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Schwob, Guillaume. "Rôle écologique de la sporulation in-planta dans les symbioses actinorhiziennes : cas de la symbiose Alnus - Frankia." Thesis, Lyon, 2018. http://www.theses.fr/2018LYSE1037/document.

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Les patrons de distribution chez les micro-organismes reposeraient sur leurs capacités à disperser dans le temps et dans l'espace, en lien avec des facteurs abiotiques comme les propriétés du sol, le climat, et des interactions biotiques, notamment avec l'hôte dans le cas des symbiontes, mais aussi sur les traits d'histoire de vie propres aux micro-organismes, telle que la capacité à sporuler. Frankia sp. est une actinobactérie sporulante et fixatrice d'azote à la biogéographie complexe, car vivant à la fois de façon saprophytique dans le sol, en symbiose racinaire (nodosité) avec les plantes
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Al, Rashed Hussain Ali. "EVALUATION OF A NOVEL ENDOPHYTE-INFECTED TALL FESCUE CULTIVAR AS A SAFE FORAGE FOR PREGNANT MARES." MSSTATE, 2009. http://sun.library.msstate.edu/ETD-db/theses/available/etd-11062009-132030/.

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Fescue toxicosis is a condition that afflicts livestock grazing endophyte-infected tall fescue and is particularly detrimental to pregnant mares. A two year evaluation study of a novel endophtye-infected cultivar, AGRFA-144 (A-144), did not induce fescue toxicosis in late-term pregnant mares. All mares delivered viable foals except in E+ group which had two viable foals, one stillborn-dystocia and one compromised foal which was euthanized at 72 h pp. Serum P4 concentrations were similar among A-144, NE+, and E- mares (p>0.05). Foal BW and foal/placental weight ratios were similar for A-144, NE
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McClanahan, Linda Kay. "Hair coat and steroidal implant effects on steers grazing endophyte-infected tall fescue during the summer." Lexington, Ky. : [University of Kentucky Libraries], 2007. http://lib.uky.edu/ETD/ukycrsc2007t00580/Thesis.pdf.

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Thesis (M.S.)--University of Kentucky, 2007.<br>Title from document title page (viewed on June 14, 2007). Document formatted into pages; contains: vii, 57 p. : ill. Includes abstract and vita. Includes bibliographical references (p. 48-56).
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Guo, Jingqi. "THE INFLUENCE OF TALL FESCUE CULTIVAR AND ENDOPHYTE STATUS ON ROOT EXUDATE CHEMISTRY AND RHIZOSPHERE PROCESSES." UKnowledge, 2014. http://uknowledge.uky.edu/pss_etds/50.

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Tall fescue (Lolium arundinaceum (Schreb.) Darbysh.) is a cool-season perennial grass used in pastures throughout the Southeastern United States. The grass can harbor a fungal endophyte (Epichloë coenophiala) thought to provide the plant with enhanced resistance to biotic and abiotic stress. However, the alkaloids produced by the common variety of the endophyte cause severe animal health issues resulting in a considerable amount of research focused on eliminating the toxic class of alkaloids while retaining the positive abiotic and biotic stress tolerance attributes of the other alkaloids. In
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Jia, Yang. "INTERACTION OF ISOFLAVONES AND ENDOPHYTE-INFECTED TALL FESCUE SEED EXTRACT ON VASOACTIVITY OF BOVINE MESENTERIC VASCULATURE." UKnowledge, 2014. http://uknowledge.uky.edu/animalsci_etds/41.

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Endophyte-infected tall fescue produces many ergot alkaloids, which have been shown to be vasoconstrictive in various vessel types of bovine. On the other hand, substantial evidence has been reported on the vasodilative effects of formononetin and biochanin A in different vessel types in humans and rats. So, a study was conducted using mesenteric vasculature collected from heifers shortly after slaughter. After 2-h incubation with formononetin (F), biochanin A (B), or an ergovaline-containing tall fescue seed extract (EXT) and their combinations, vessels were mounted in a multi-myograph to det
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Zylka, Christine A. "Composition and nutrient utilization by sheep of ensiled tall fescue with different levels of endophyte infection." Thesis, Virginia Polytechnic Institute and State University, 1989. http://hdl.handle.net/10919/52098.

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Low and high endophyte infected stockpiled tall fescue was harvested, chopped and ensiled in 210 liter metal drums, double lined with polyethylene bags. Endophyte infection averaged 4 and 70%, respectively, for the low- and high-endophyte fescue. A metabolism trial was conducted with 24 wethers fed diets consisting of 100% low-endophyte fescue silage, 50% low-endophyte and 50% high-endophyte fescue silage, and 100% high-endophyte fescue silage. Chopped alfalfa hay was used as a control forage. Single samples were analyzed, so statistical treatment of chemical composition was not possible. Howe
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Hanneman, Jessica Marie. "EFFECTS OF ENDOPHYTE-INFECTED TALL FESCUE SEED AND BROMOCRIPTINE ON ENDOCRINE AND IMMUNE FUNCTION IN HORSES." UKnowledge, 2018. https://uknowledge.uky.edu/gluck_etds/38.

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Consumption of endophyte-infected (E+) grasses has long been associated with health problems in animals. In cattle E+ tall fescue consumption leads to fescue toxicosis, and in horses it leads reproductive problems. The health-related issues associated with endophyte consumption have been attributed to the effects caused by the ergot alkaloids produced by the fungus. These ergot alkaloids are considered D2-like receptor agonists, and 5-HT2 serotonin and α-adrenergic receptor partial agonists. Many studies in humans, swine, cattle, and horses have identified that ergopeptines cause a decrease in
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Kuntz, Veronica L. "The relationship between Sarracenia oreophila and an endophytic Burkholderia." Thesis, Georgia Institute of Technology, 2011. http://hdl.handle.net/1853/41094.

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Plant growth-promoting bacteria (PGPB) have been studied in many agriculturally interesting plants, but never in pitcher plants. Sarracenia oreophila (the green pitcher plant) is an endangered species in Georgia, Alabama, and North Carolina (Rice 2010). With the help of Dr. Jim Spain's lab, a previous student in Dr. Gerald Pullman's lab discovered evidence that nitrogen-fixing bacteria (Burkholderia spp.) live within these pitcher plants. This study aims to determine whether these nitrogen-fixing bacteria confer a benefit to their host plants by providing fixed nitrogen. To do this, pitcher p
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Rotz, Jonathan Daniel. "Comparison of techniques for estimating pasture herbage mass and productive ground cover for Lakota prairie grass, Kentucky 31 endophyte free tall fescue, Kentucky 31 endophyte infected tall fescue and Quantum 542 tall fescue grazed by stocker steers." Thesis, Virginia Tech, 2006. http://hdl.handle.net/10919/42188.

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In terms of acreage, forage is the number one crop in Virginia. The backbone of these forages has long been tall fescue (Lolium arundinaceum (Schreb.) S.J. Darbyshire). Knowledge of the plant species that make up a pasture and the relative amounts of each species present is important for interpreting potential animal performance. It is also important to know the relative amounts and types of weeds present and to monitor for the presence of poisonous plants or noxious weeds. An experiment was conducted in 2003 through 2005 to investigate botanical composition and yield of â Lakotaâ prair
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Saliba, Sahar. "Nouvelles approches biotechnologiques pour l’obtention d’alcaloïdes : culture in vitro de Leucojum aestivum L. et isolement d’endophytes bactériens d’Amaryllidaceae." Thesis, Université de Lorraine, 2015. http://www.theses.fr/2015LORR0107/document.

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Plus de 300 alcaloïdes d’Amaryllidaceae doués d’activités biologiques ont été isolés à partir des plantes appartenant à cette famille. De nos jours, seule la galanthamine, utilisée pour le traitement palliatif de la maladie d’Alzheimer, est commercialisée. L’accumulation de ces alcaloïdes dans les plantes est limitée. La culture in vitro est une méthode alternative intéressante pour l’obtention plus aisée de ces alcaloïdes à haute valeur ajoutée. Le premier objectif de ce travail vise à développer une méthode de purification efficace, simple et rapide des extraits de plantes préalablement à le
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Grancher, Denis. "Extraction, purification, toxicocinétique chez la chèvre et toxicologie clinique d'une toxine de champignon endophyte : le lolitrème B." Clermont-Ferrand 2, 2007. http://www.theses.fr/2007CLF21744.

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Le lolitrème B est une mycotoxine d'un champignon endophyte du genre Neotyphodium qui provoque des symptômes nerveux. L'objectif était de mesurer l'importance épidémiologique de cette intoxication et d'étudier son impact en santé publique vétérinaire (toxicocinétique, passage dans le lait). L'étude de cas cliniques a montré une relation entre la létalité et les teneurs relatives en lolitrème B et ergovaline. En France, les cas observés étaient dus à des pailles de Raygrass-semences. La toxicocinétique a nécessité l'extraction et la purification de lolitrème B. La chromatographie à contre coura
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MICELI, Elisangela. "Bacterial Endophytes: Unexplored Sources Of Biotechnologically Relevant Molecules." Doctoral thesis, Università degli studi di Ferrara, 2019. http://hdl.handle.net/11392/2488023.

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Endophytes are microorganisms which colonize the internal tissues of the plants without causing any harm. Generally, endophytes are described as presenting beneficial functions to the plant host, such as plant growth promoting activity and protection against pathogens. The interaction between endophytes and plants is so close, that the term holobiont has been proposed to define the plant and its microbiome, as if they formed a unique organism. In the last decades, endophytes have gained more attention since there is growing evidence of their capacity to influence the plant’s physiology and to
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50

Florea, Simona. "TOWARDS ELIMINATION AND GENETIC MANIPULATION OF ERGOT ALKALOID PRODUCTION IN FUNGAL ENDOPHYTES." UKnowledge, 2009. http://uknowledge.uky.edu/gradschool_diss/803.

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Clavicipitaceous fungal endophytes provide several ecological benefits to their hosts. Besides improving host’s growth characteristics, Neotyphodium coenophialum, the endophyte of tall fescue (Lolium arundinaceum), produces ergot alkaloids that have been proposed to be involved in fescue toxicosis. One approach to address the toxicosis problem is to genetically manipulate and modify N. coenophialum by knocking out a pair of homologous genes, (dmaW1 and dmaW2), encoding dimethylallyltryptophan synthase, the enzyme for the first and determinant step in ergot-alkaloid biosynthesis. In this study,
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