In this thesis I investigated the mutualism between Kunzea ericoides (kanuka) and two groups of soil fungi, ectomycorrhizae (ECM) and arbuscular mycorrhizae (AMF). Mycorrhizal mutualisms, which are considered globally ubiquitous, are poorly understood over changing abiotic gradients. A field survey of K. ericoides assessed how the relationship with the soil fungi varieties altered over a hydrologic gradient. Arbuscular mycorrhizal colonisation was significantly improved by increasing rainfall levels and amount of surrounding kanuka, and negatively affected by increasing altitude. Ectomycorrhizal colonisation was not significantly affected by any measured variables and remained relatively constant across all circumstances, suggesting that it is the preferred fungal mutualist for this tree species. A glasshouse experiment was done to measure the effect of ECM inoculation on the growth and water usage of K. ericoides over varying moisture availability. The seedlings were planted in soil inoculated with both ECM and AMF (experimental) or AMF only (control) and then grown under varying levels of water stress. The experiment was replicated with two soil types, with soil from beneath adult manuka (Leptospermum scoparium) and soil from beneath adult kanuka (K. ericoides). ECM colonisation significantly increased as soil moisture decreased for both soil types. ECM inoculation also increased the root:shoot ratio, and drastically decreased water usage under drought conditions. There were some soil effects as the seedlings grown in manuka-soil achieving greater biomass than seedlings grown in kanuka-soil. This is possibly due to presence of pathogens or some type of legacy competition which the seedlings would experience growing near conspecifics. Overall, K. ericoides formed a dominant mutualism with ectomycorrhizae. These two both thrive in dry environmental conditions and have a suite of complementing abilities which possibly allow K. ericoides to expand it range into these dry habitat types. The increased benefit of these mutualisms at the hydrologic range limit of the species supports the importance of biotic interaction mediating environmental stress. Understanding the effects and response of mycorrhizal mutualisms are especially significant considering current climate change issues in New Zealand and worldwide.

Thickets of Rhododendron maximum (Rm) in the southern Appalachians impose severe limitations on the regeneration of hardwood and coniferous seedlings. Interactions between Rm thickets and ectomycorrhizal colonization were examined to explain seedling inhibition. Experimental blocks were established in and out of Rm thickets in a mature, mixed hardwood/conifer forest in Macon County, North Carolina. Planted seedlings of red oak (Quercus rubra) and hemlock (Tsuga canadensis) were harvested at the end of the first and second growing seasons. Litter manipulation had no effect on total mycorrhizal colonization. Mycorrhizal colonization and ramification index (# mycorrhizae cm-1) were depressed and colonization by Cenococcum geophilum increased in blocks with versus without Rm. After the first year, percent colonization of T. canadensis not in Rm thickets (62 %) was three times higher than in Rm thickets (19%), and the ramification index was increased by more than a factor of four (2.83 versus 0.61). Mycorrhizal colonization levels were correlated with root weight and shoot weight in both hemlock and oak seedlings, but did not explain most of the variation observed. Sporocarps of 69 putatively ectomycorrhizal species were collected on the blocks. Species diversity and overall community structure was similar in and out of Rm thickets. Individual species, i.e. Lactarius speciosus and Russula krombholzii, were significant indicators of forest without Rm thickets. Rhododendron maximum thickets probably affect the process of mycorrhization. The reduced level of mycorrhizal capacity under Rm thickets could be a factor in the increased seedling failure in Rm thickets. / Master of Science

This PhD thesis follows my master's thesis, which I focused on the problem of uranium determination and content in macrofungal fruit-bodies (the results have been published, Appendix 1). Macrofungi apparently do not accumulate uranium in fruit-bodies but as other studies suggested major roles of fungi in environmental geochemistry of uranium, I hypothesized possible accumulation of uranium and other elements in ectomycorrhizae. I therefore decided to continue the research and focus on investigation of trace elements in ectomycorrhizae. As I had opportunity to use a variety of analytical methods, I also participated in other studies in the field geomycology and the results are included in this thesis. In response to alarmist reports in Czech media, I focused on activity and distribution of radiocaesium in fruit-bodies of Boletus badius. As demonstrated in Appendix 2, the fruit- bodies of this species do not represent a health risk for mushroom consumers. Distribution of mycelium of saprotrophic Agaricus bernardii in a soil profile in Prague was investigated by use of molecular methods (PCR with specific primers). The results have shown that the mycelium reaches the depth of 30 cm. Lead isotopic composition of fruit- bodies suggests lead can be accumulated from soil depth of 13-17 cm (Appendix 3)....

The Oak Ridge Reservation established under The Atomic Energy Commission was the site for uranium enrichment and the construction of the atomic bomb during the early 1950’s and 60’s. Unfortunately, large quantities of “heavy metals” such as mercury, uranium, technetium, plutonium and fission products that were produced were dumped into unlined landfills, settling ponds and surface streams. One such creek affected was East Fork Poplar Creek, whose head water begins at the Y-12 Facilities located on the Oak Ridge Reservation, and was once used as an industrial drainage ditch for runoff, which included mercury and other heavy metals. The release of mercury, in particular, into East Fork Poplar Creek was probably lethal to established seed banks, vegetation, and soil microbial and fungal communities. The soil microbial communities play an important role in ecological processes, and the fungal communities are important, in particular, due to the mutualistic associations shared with more than 85% of plant species. This study evaluating the long term effects of mercury on plant and fungal presence and abundance indicated that soil mercury concentration was not significantly correlated with these factors. In order to better understand the effects of mercury compounds on plant and fungal interaction, a greenhouse study was conducted. Survival of seedlings in mercury-contaminated media was more dependent on mercury compound applied than on the presence of fungal inoculates tested. The ability of four tree species to germinate in different mercury compounds was also investigated. The germination of seedlings in mercury solution was dependent on tree species, mercury compound and concentration. The detection of mercury in environmental samples was based on conventional methods such as cold vapor atomic absorption spectroscopy (CVAAS), and inductively coupled plasma emission mass spectrometer (ICP-MS). Analysis of mercury and other metals by non-destructive techniques such as infrared spectroscopy, specifically near-infrared (NIR) and mid-infrared (MIR) spectroscopy was investigated. Quantitative analysis of plant foliar tissue exposed to mercury was investigated by NIR, and mercury- contaminated soil was investigated by MIR. Due to mercury’s volatility, the ability to differentiate NIR spectra of control versus treated seedlings could not be confirmed through statistical analysis, however MIR spectra obtained from mercury-contaminated soil was used to develop significant calibration models for mercury and several other metals correlated to mercury.

<p>The truffle genus Tuber (Ascomycota, Pezizales, Tuberaceae) produces underground mushrooms widely sought as edible fungi. Tuber species are distributed throughout Northern hemisphere forests and form obligate ectomycorrhizal symbiosis with trees within the Pinaceae, Fagaceae, Betulaceae, and Juglandaceae. </p><p>The transition to a truffle form (from an epigeous form) has occurred independently, multiple times in both the Ascomycetes and Basidiomycetes. One instance has given rise to the Tuberaceae, which is composed entirely of obligate ectomycorrhizal species. Attempts to cultivate European truffle species T. melanosporum, T. aestivum, and T. borchii are underway in North America and other parts of the world and have been met with mixed success.</p><p>The overarching goal of my dissertation is to address the systematics, ecology, and biogeography of Tuber within a phylogenetic framework. Multiple loci were sequenced from Tuber ascoma collected worldwide including ectomycorrhizae, though an emphasis was placed on sampling taxon within North American. Maximum likelihood, maximum parsimony, and Bayesian inference were used for phylogenetic reconstructions. </p><p>A taxonomic and phylogenetic overview of the family Tuberaceae is presented in Chapter 1. Tuber is resolved as monophyletic. In Chapter 2, through greater taxon sampling including epigeous and hypogeous Helvellaceae outgroups and related South American taxa, a resolved multi-gene phylogeny of the Tuberaceae and putative epigeous ancestor of Tuber is presented. A previously unknown South American lineage that contains both epigeous and hypogeous taxa is resolved as sister to the Tuberaceae. Chapter 3 is focused on issues of cryptic speciation and taxonomy within the Tuber gibbosum clade. The four species resolved in the Gibbosum clade appear to be endemic to the Pacific Northwest and associated primarily with Gymnosperms. Chapter 4 is a meta-analysis of all known Tuber ITS rDNA sequences (e.g. from Genbank and generated from herbarium collections) available at the time. These were placed within the Tuber phylogeny to assess species diversity, long-distance dispersal, and host associations. In total, 120 phylotypes were detected (based on a 96% similarity criterion). Tuber shows high levels of continental endemism. I hypothesize that species shared between continents and having low ITS variability (<1%) are the result of recent human-mediated introduction events. Chapters 5 and 6 are focused on the ectomycorrhizal ecology of the economic truffle T. lyonii, which is native to Eastern and Southern North America. There is a phenomenon of Tuber lyonii fruiting in pecan orchards. Pecans (Carya illinoinensis) are in the Juglandaceae, an understudied ectomycorrhizal plant family. I sampled the ectomycorrhizal communities of pecan orchards (associated with the production of the North American truffle species Tuber lyonii). In Chapter 5 I discuss four Tuber taxa discovered in these pecan orchards, their abundance and haplotype diversity. Chapter 6 examines the ectomycorrhizal communities across the five pecan orchards sampled. I show that multiple Tuber species, including Tuber lyonii, are dominant in the ectomycorrhizal community. Chapters 7 and 8 focus on black truffles in the Melanosporum clade. In Chapter 7 I document that Tuber indicum has been introduced into North America multiple times, and through ectomycorrhizal synthesis I demonstrate that this Asian species can associate readily with angiosperm and gymnosperm hosts endemic to North American. In Chapter 8 I describe a quick and reliable method for the determination of Tuber melanosporum. The method is based on direct PCR and species-specific primers and is very useful for rapid diagnostics. I have adapted this approach for other truffle and mushroom species. </p><p>Three major findings emerge from my dissertation research: 1) Tuber is more diverse than previously realized; 2) Tuber exhibits high levels of regional and continental endemism; 3) Taxonomic issues remain in many species complexes worldwide (including the Tuber candidum complex in North America, the Tuber excavatum complex in Europe, the Tuber indicum complex in Asia). Taxonomic challenges also remain regarding species known only from ectomycorrhizal or anamorphic states. The discovery of additional Tuber species is expected as the truffle flora of undersampled regions become better studied and incorporated into the Tuberaceae phylogeny.</p> / Dissertation

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / Ectomycorrhizal fungi (fECM) combined with the plant root system improve the absorption of water and nutrients, providing great plant growth, especially in environments with nutritional deficiency or degraded. Due to the fECM and plants live in mutualistic association, allows the fungal symbionts to be benefit, or at least tolerate, the secondary metabolites produced by plants. It is possible that essential oils extracted from forest species that form mycorrhizal associations by stimulating the growth of ectomycorrhizal isolates and benefit the plant-fungus symbiosis. This study aimed to evaluate the effect of Eucalyptus grandis W. Hill ex. Maiden essential oil, the inoculum production of fECM and its influence on the tolerance of the isolates to heavy metals copper, zinc and nickel. Also, determines the effect of the use of essential oil on growth of eucalyptus (Eucalyptus grandis) and sibipiruna (Caesalpinia peltophoroides) seedlings in the greenhouse and the establishment of eucalyptus soil contaminated by copper under controlled conditions and field. The evaluation of the effect of different eucalyptus essential oil concentrations to stimulate the growth of fECM Pisolithus sp. (UFSC Pt 24 and UFSC Pt 188), Pisolithus microcarpus (UFSC Pt 116), Chondrogaster angustiporus (UFSC Ch 163), Scleroderma citrinum (UFSC Sc 124) and Suillus sp. (UFSM RA 2.2 and UFSM RA 2.8) in liquid culture medium MNM, allow to observe that the addition of eucalyptus essential oil concentrations 20 and 30 μL L-1 promoted an increase in mycelium growth in vitro of the isolates UFSC Pt 24, UFSC Pt 116, Ch 163 UFSC, UFSC Sc 124, UFSM RA 2.2 and UFSM RA 2.8. In liquid culture medium containing heavy metals copper, zinc and nickel. It was observed that the addition of essential oil at concentration of 20 μL L-1 increased the growth of ectomycorrhizal isolates. The evaluation of use of essential oil extracted from eucalyptus leaves on germination and initial development of eucalyptus seedlings in nursery conditions, permits to observe that germination was significantly highest when the seeds were sprayed with 25 μL L-1 oil essential. The application of essential oil at concentrations of 30 and 40 μL L-1 improve the development of roots and shoots of eucalyptus seedlings in a controlled environment. This can be an effective alternative in the biostimulation of the vegetative growth of eucalyptus seedlings. The effect of the use of essential oil was also positive when applied to eucalyptus seedlings inoculated 90 days after inoculation, improving both the mycorrhizal and seedling growth. Evaluating the effect of eucalyptus essential oil in the formation of ectomycorrhizal association and growth of sibipiruna seedlings after 90 days under greenhouse conditions. It was found that the application of essential oil enhanced the association of ectomycorrhizal fungus P. microcarpus and the development in seedlings of sibipiruna seedlings. The assessment of the degree of mycorrhizal association was determined by the percentage of mycorrhization. Eucalyptus seedlings grown in fertilized substrate, by using of essential oil in the formulation of inoculant or through subsequent application resulted in plants with highest height, fresh and dry weight, diameter and adaptability in soil contaminated by copper. These results may improve the establishment of mycorrhizal fungi in seedlings of sibipiruna seedlings as well as development and growth of eucalyptus seedlings in sites contaminated by heavy metals. / Os fungos ectomicorrízicos (fECM) em associação com o sistema radicular das plantas, auxiliam na absorção de água e nutrientes, proporcionando maior crescimento vegetal, principalmente em ambientes com deficiência nutricional ou degradados. Os fECM e as plantas ao conviverem em associação mutualística, permitem que os fungos simbiontes se beneficiem, ou pelo menos tolerem, os metabólitos secundários produzidos pelas plantas hospedeiras. É possível que os óleos essenciais extraídos de essências florestais conhecidamente micossimbiontes possam estimular o crescimento de isolados ectomicorrízicos e beneficiar a simbiose fungo-planta. O trabalho teve como objetivos determinar o efeito do óleo essencial de Eucalyptus grandis W. Hill ex. Maiden na produção de inóculo de fECM e sua influência na tolerância dos isolados aos metais pesados cobre, zinco e níquel; e determinar o efeito da utilização do óleo essencial no crescimento de mudas de eucalipto (Eucalyptus grandis) e sibipiruna (Caesalpinia peltophoroides) em casa de vegetação e no estabelecimento de eucalipto em solo contaminado por cobre em condições controladas e a campo. A avaliação do efeito de diferentes concentrações do óleo essencial de eucalipto no estímulo ao crescimento dos fECM Pisolithus sp. (isolados UFSC Pt 24 e UFSC Pt 188), Pisolithus microcarpus (isolado UFSC Pt 116), Chondrogaster angustiporus (isolado UFSC Ch 163), Scleroderma citrinum (isolado UFSC Sc 124) e Suillus sp. (isolados UFSM RA 2.2 e UFSM RA 2.8) em meio de cultura líquido MNM, permite observar que a adição do óleo essencial de E. grandis nas concentrações de 20 a 30 μL L-1 promoveu incremento no crescimento miceliano in vitro nos isolados UFSC Pt 24, UFSC Pt 116, UFSC Ch 163, UFSC Sc 124, UFSM RA 2.2 e UFSM RA 2.8. No meio de cultura líquido contendo os metais pesados cobre, zinco e níquel, observou-se que a adição do óleo essencial na concentração de 20 μL L-1 favoreceu o crescimento de isolados ectomicorrízicos. Avaliando-se a utilização do óleo essencial extraído de folhas de eucalipto sobre a germinação e o desenvolvimento inicial de mudas de eucalipto em condições de viveiro, observou-se que a germinação foi superior quando as sementes foram pulverizadas com 25 μL L-1 do óleo essencial. A aplicação do óleo essencial nas concentrações de 30 e 40 μL L-1, proporcionou maior desenvolvimento das raízes e da parte aérea das mudas de eucalipto em ambiente controlado. Isso pode ser uma alternativa eficiente na bioestimulação do crescimento vegetativo de mudas de eucalipto. O efeito da utilização do óleo essencial também foi positivo quando aplicado em mudas de eucalipto micorrizadas após 90 dias de inoculação, favorecendo tanto a micorrização como o crescimento das mudas. Avaliando-se o efeito do óleo essencial de eucalipto na formação de associação ectomicorrízica e no crescimento de mudas de sibipiruna após 90 dias em condições de casa de vegetação, verificou-se que a aplicação do óleo essencial favoreceu a associação ectomicorrízica, determinada através do porcentual de micorrização, do fungo P. microcarpus e o desenvolvimento em mudas de sibipiruna. Mudas de eucalipto formadas em substrato micorrizado, utilizando o óleo essencial na formulação do inoculante ou via aplicação posterior, resultaram em plantas com maior altura, massa fresca e seca, diâmetro do colo e capacidade de adaptação em solo contaminado por cobre. Esses resultados demonstram que a utilização do óleo essencial de eucalipto pode favorecer o estabelecimento de associação micorrízica em mudas de sibipiruna, bem como o crescimento e desenvolvimento de mudas de eucalipto em áreas contaminadas por metais pesados.

No description available.

No description available.

Made available in DSpace on 2014-12-17T14:10:18Z (GMT). No. of bitstreams: 1 FranciscoEG.pdf: 1575476 bytes, checksum: 69b3b246ecaefc37e28526c15d4b4ba0 (MD5) Previous issue date: 2009-03-06 / Ectomycorrhizal associations are poorly known from tropical lowlands of South America. Recent field trips to the reserve Parque Estadual das Dunas in Natal, in Rio Grande do Norte state, Brazil, revealed a undocumented community of ectomycorrhizal fungi. This type of Mycorrhizal association is frequently in the north hemisphere in temperate and boreal forests. The aim of this work is to analyze the occurrence of ectotrophic areas in atlantic rainforest. Collections along and around the trails in the reserve revealed six genera of putatively ECM fungi which belong to the basidiomycete, Amanitaceae, Boletaceae, Russulaceae, Entolomataceae, and Sclerodermataceae family which are poorly documented in Brazil. Plants belonging to Myrtaceae, Polygonaceae, Leguminosae/Caesalpinioideae, Erythroxylaceae, Malphigiaceae, Bromeliaceae, Loganiaceae, Sapotaceae e Celastraceae were found living next to the species of fungi analized. Our results suggest that the area studied is an ectotrophic environment which shows high diversity of putatively ECM fungi and some plants probably host ECM. The tropical lands are a potential focus to study reinforced by the new records of Scleroderma in Brazil and Northwest of Brazil / As associa??es ectomicorr?zicas nos tr?picos e principalmente nas regi?es de mata nativa na Am?rica do Sul s?o pouco conhecidas. Sabe-se que esse tipo de associa??o ocorre predominantemente no hemisf?rio norte em florestas temperadas e boreais. O objetivo deste trabalho ? verificar a ocorr?ncia de ambientes ectotr?ficos em ?reas de mata atl?ntica. Estudos de campo feitos no Parque Estadual Dunas do Natal, no Estado do Rio Grande do Norte, relevou uma comunidade de fungos ectomicorr?zicos. Seis g?neros de fungos ectomicorr?zicos foram encontrados em coletas realizadas ao longo das trilhas do Parque, os quais pertencem a fam?lias de basidiomicetos Amanitaceae, Boletaceae, Russulaceae, Entolomataceae, e Sclerodermataceae, cujos registros s?o escassos para o Brasil. Tamb?m foram encontradas plantas pertencentes ?s fam?lias Myrtaceae, Polygonaceae, Leguminosae/Caesalpinioideae, Erythroxylaceae, Malphigiaceae, Bromeliaceae, Loganiaceae, Sapotaceae e Celastraceae coocorrendo com os esp?cimes de fungos encontrados. Os resultados sugerem que o Parque das Dunas se caracteriza como uma ?rea ectotr?fica, apresentando uma alta diversidade de fungos ectomicorr?zicos e algumas fam?lias de plantas com incid?ncia ectomicorr?zica. Verificou-se ainda um potencial objeto de estudo em ?reas de mata atl?ntica refor?ado pelos novos registros de Scleroderma tanto para o nordeste do Brasil quanto para o pa?s

Abstract Boreal urban forests are becoming more and more fragmented and, at the same time, are exposed to low-level but long-term nitrogen and sulphur deposition. Natural mid-boreal forests are dominated by few tree and shrub species, while herbs and grasses are rare. Soils in mid-boreal forests are rich in ectomycorrhizal (ECM) fungi, forming a symbiotic relationship with forest trees, which is important for the nutrient cycle especially in nutrient-poor ecosystems. Aims of this thesis were 1) to study differences between mid-boreal urban and rural forests in composition of macrofungi and structure of plant communities, 2) to explore whether responses of Scots pine seedlings to excess N are mediated via soil or via air, and 3) to study if partial removal of vegetation and humus layer alleviates the adverse effects of excess N on plant and fungal communities, and promotes performance and regeneration of Scots pine in urban forests. The growth responses of seedlings and their mycorrhizal colonization were studied in both field and greenhouse experiments. Peroxidase (POD) activity was used as a root stress indicator. Urban forests were poor in number of fruiting ECM fungal species, but rich in herbs and grasses in the field layer, as compared to rural forests. These differences were thought to result from changes in soil properties. ECM fungal colonization in Scots pine roots did not respond significantly to high nitrogen load in soil, but high root POD activity indicated changes in root physiology. ECM macrofungal diversity in urban forests was not markedly increased during a five-year survey after a partial humus removal treatment. On the other hand, fruiting of Cortinarius semisanguineus is a positive response to the treatment. Scots pine seedling emergence was poor due to rapid revegetation at the urban sites, but the treatment promoted both root and shoot growth of planted Scots pine seedlings in urban forests. Decreased root POD activity in Scots pine seedlings in the humus removal treatment possibly indicates lowered root stress. Soil manipulations may result in a risk of nutrient leakage, and a risk of invasion by non-typical plants. Also, small stand size with high recreation pressure causes a risk for tree regeneration in urban forest stands. These risks need to be considered when planning management of urban coniferous forests.