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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
11

Physical processes affecting soil biotic and abiotic responses to disturbance in forest ecosystems of southwestern Oregon /

Borchers, Jeffrey G. January 1990 (has links)
Thesis (Ph. D.)--Oregon State University, 1990. / Typescript (photocopy). Includes bibliography (leaves 142-152). Also available on the World Wide Web.
12

Impact of atmospheric nitrogen pollution on belowground mycorrhizal fungal community structure and composition in the San Bernardino Mountains

Sirajuddin, Ayesha Tasneem. January 2009 (has links)
Thesis (Ph. D.)--University of California, Riverside, 2009. / Includes abstract. Includes bibliographical references. Issued in print and online. Available via ProQuest Digital Dissertations.
13

Mycorrhizae, water, and a changing climate how do trees survive in a seasonally dry tropical forest? /

Hasselquist, Niles Jacob, January 2009 (has links)
Thesis (Ph. D.)--University of California, Riverside, 2009. / Includes abstract. Includes bibliographical references (leaves ). Issued in print and online. Available via ProQuest Digital Dissertations.
14

Effect of a Trichoderma bio-inoculant on ectomycorrhizal colonisation of Pinus radiata seedlings : a thesis submitted in partial fulfilment of the requirements for the degree of Master of Science at Lincoln University /

Minchin, R. F. January 2010 (has links)
Thesis (M. Sc.) -- Lincoln University, 2010. / Also available via the World Wide Web.
15

Toler?ncia de isolados de Pisolithus sp. a cupinicidas / Pisolithus sp. isolated of tolerance at termiticides

Antunes, L?dia Alves 19 August 2016 (has links)
?rea de concentra??o: Produ??o vegetal. / Submitted by Jos? Henrique Henrique (jose.neves@ufvjm.edu.br) on 2017-04-12T18:35:18Z No. of bitstreams: 2 license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) lidia_alves_antunes.pdf: 917012 bytes, checksum: b4a549d8c4b68dbfd230aee1440375df (MD5) / Approved for entry into archive by Rodrigo Martins Cruz (rodrigo.cruz@ufvjm.edu.br) on 2017-04-24T17:43:24Z (GMT) No. of bitstreams: 2 license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) lidia_alves_antunes.pdf: 917012 bytes, checksum: b4a549d8c4b68dbfd230aee1440375df (MD5) / Made available in DSpace on 2017-04-24T17:43:24Z (GMT). No. of bitstreams: 2 license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) lidia_alves_antunes.pdf: 917012 bytes, checksum: b4a549d8c4b68dbfd230aee1440375df (MD5) Previous issue date: 2016 / Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior (CAPES) / A imers?o de mudas de eucalipto em solu??es de cupinicidas antes do plantio pode influenciar o desempenho de programas de inocula??o com fungos ectomicorr?zicos (FEM) em viveiros comerciais, pois estes inseticidas podem interferir na simbiose. O objetivo deste trabalho foi avaliar a toler?ncia de isolados de Pisolithus sp. aos cupinicidas thiamethoxam, imidacloprid e fipronil. Discos de 5 mm de meio de cultura com mic?lio dos isolados D5, D17, D95, D216, D29, D10, D15, C9C, C16 e C13 de Pisolithus sp. foram pr?-imersos em solu??es com 3 g L-1 de thiamethoxam, 7,5 g L-1 imidacloprid e 7,5 g L-1 de fipronil. Ap?s este procedimento foram colocados para crescer por 10 dias em meio de cultura Melin-Norkrans modificado (MNM). Os cupinicidas foram avaliados em experimentos independentes. Em outra s?rie de experimentos, discos 5 mm dos isolados D5, D10 e D216 foram colocados para crescer por 20 dias em meio de cultura contendo 0 (controle), 0,4; 0,8 e 1,6 g L-1 de thiamethoxam, 3; 6 e 12 g L-1 de imidacloprid e 0 (controle); 3; 6 e 12 g L-1 de fipronil. O efeito dos cupinicidas sobre fungos ectomicorr?zicos foi dependente do isolado, do princ?pio ativo, do tempo de exposi??o e da concentra??o do cupinicida. Os isolados mais tolerantes a pr?-imers?o do mic?lio nos cupinicidas foram o C9C para o thiamethoxam, o D15 para o imidacloprid e o D10 para o fipronil. Os tr?s cupinicidas foram t?xicos aos isolados de Pisolithus sp. quando estes foram adicionados ao meio de cultura. Em geral, thiamethoxam foi o menos t?xico para os isolados de Pisolithus sp.. / Disserta??o (Mestrado) ? Programa de P?s-Gradua??o em Produ??o Vegetal, Universidade Federal dos Vales do Jequitinhonha e Mucuri, 2016. / The immersion eucalyptus seedlings in termiticides solutions before planting can influence the performance of inoculation programs with ectomycorrhizal fungi (EMF) in commercial nurseries, as these insecticides can interfere with symbiosis. Study aimed at assessing the tolerance of Pisolithus sp. isolates to the termiticides thiamethoxam, imidacloprid and fipronil. 5-mm-diameter circular sections of culture medium with the mycelial isolates D5, D17, D95, D216, D29, D10, D15, C9C, C16 and C13 Pisolithus sp. were pre-dipped in solutions with 3 g L-1 of thiamethoxam, 7.5 g L-1, 7.5 g L-1 imidacloprid and fipronil. Next were placed let grow for 10 days through the cultured on modified Melin-Norkrans (MNM) solid medium. The termiticides were through independent testing. In another series of experiments, 5-mm-diameter circular sections of culture medium with the mycelial isolates D5, D10 and D216 were placed let grow for 20 days in solid medium containing 0 (control) 0.4; 0.8 and 1.6 g L-1 thiamethoxam 3; 6; 12 g L-1 of imidacloprid and 0 (control); 3; 6; 12 g L-1 fipronil. The effect of termiticides on ectomycorrhizal fungi was dependent of isolated, of active ingredient, of exposure time and concentration of termiticide. The most tolerant isolates the pre-soaking the mycelium in termiticides were C9C for thiamethoxam, the D15 for imidacloprid and D10 for fipronil. The three termiticides were toxic to isolates Pisolithus sp. when they were added to the culture medium. In general, thiamethoxam was less toxic to isolates Pisolithus sp.
16

Occurrence of ectomycorrhizae on ericaceous and coniferous seedlings grown in soils from the Oregon Coast Range /

Smith, Jane E. January 1993 (has links)
Thesis (M.S.)--Oregon State University, 1993. / Typescript (photocopy). Includes bibliographical references (leaves 40-50). Also available on the World Wide Web.
17

Effects of prescribed burning upon mycorrhizal fungal diversity inhabiting the roots of two and a half-year old black spruce (Picea mariana) : molecular characterization of ectomycorrhizal fungi via PCR/RFLP analysis /

Baldwin, Quentin F., January 1999 (has links)
Thesis (M.Sc.), Memorial University of Newfoundland, 1999. / Bibliography: p. 208-219.
18

Diversity and function of root-associated fungal communities in relation to nitrogen nutrition in temperate forests

Nguyen, Quang Dung 18 July 2018 (has links)
No description available.
19

Mycorrhizal association, propagation and conservation of the myco-heterotrophic orchid Rhizanthella gardneri

Mursidawati, Sofi January 2004 (has links)
Many orchids require mycorrhizal symbioses with fungi for their development and survival. Rhizanthella gardneri the Western Australian underground orchid is associated with the companion plant Melaleuca uncinata and its ectomycorrhizal fungus symbiont. Much less is known about the habitat requirements of its sister species, R. slateri, which occurs in Eastern Australia. The absence of chlorophyll from Rhizanthella gardneri and R. slateri results in total dependency on associations with fungal symbionts. Many ecological and biological aspects of these fascinating orchids remained poorly known, including the identity of the fungal associates and the nature of their tripartite associations with Rhizanthella and Melaleuca. Extremely high specificity of these mycorrhizal relationships is likely to be the most important factor explaining the highly specific habitat requirements of underground orchids. The purpose of this study was to conduct further investigations of the role of the mycorrhizal associations of Australian underground orchids by identifying the fungi involved in these associations, optimising their growth in sterile culture and devising efficient means for synthesising their tripartite associations with R. gardneri and M. uncinata. In total, 16 isolates of fungi were successfully obtained from the two underground orchids and used in a series of experiments to understand both the nature of the fungi and their relationship with orchids. The identity of these fungi was established by using conventional morphological and molecular methods. Cultural and morphological studies revealed that all isolates from R. gardneri and R. slateri were binucleate rhizoctonias with affinities to members of the genus Ceratobasidium. However, the teleomorph state that was observed from the R. slateri symbiont during this study more closely resembled a Thanatephorus species. Further identification using ITS sequence comparisons confirmed that mycorrhizal fungi of Rhizanthella belonged to the Rhizoctonia alliance with relatives that include Thanatephorus, Ceratobasidium, or Rhizoctonia from other continents with over 90% similarity. Most of these related fungi are known as plant pathogens, but some were orchid mycorrhizal fungi. However, the isolates from the two underground orchids were most closely related to each other and formed a discrete group relative to other known members of the Rhizoctonia alliance. Sterile culture experiments determined culture media preferences for mycorrhizal fungi from Rhizanthella and other orchids. A fully defined sterile culture medium designed to more closely resemble Australian soil conditions was formulated. This new medium was compared to undefined media containing oats or yeast extract and recommendations for growth of these fungi are provided. The undefined media based on oats provided the best growth of most fungi, but the new Australian soil media was also effective at growing most orchid mycorrhizal fungi and this fully defined media was less prone to contamination and should provide more reproducible results. A comparison of three methods for inoculating M. uncinata with the underground orchid fungi resulted in the production and characterisation of ectomycorrhizal roots and hyphae formed by fungi isolated from R. gardneri and R. slateri. These underground orchid fungi could easily be distinguished from other mycorrhizal fungi (caused by airborne contamination) by the characteristic appearance of these roots and hyphae. A new system for growing and observing tripartite mycorrhizal associations was devised using pots with side viewing windows and the use of transparent seed packets to contain Rhizanthella seeds. This method allowed all the stages of seed germination to be observed in the glasshouse, culminating in the production of underground orchid rhizomes. Seed germination was only successful when seed was placed directly over active M. uncinata ectomycorrhizas confirmed to belong to the correct fungus by microscopic observations through the side of window pots. The importance of these new scientific discoveries concerning the biology and ecology of the underground orchids and their associated fungi for the recovery of these critically endangered orchids are discussed.
20

Effect of Alliaria petiolata invasion on ectomycorrhizal colonization of Quercus rubra

Castellano, Steven Michael. January 2008 (has links)
Thesis (M.S.)--Miami University, Dept. of Botany, 2008. / Title from first page of PDF document. Includes bibliographical references (p. 22-29).

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