Thesis (Ph.D.)--University of Adelaide, School of Earth and Environmental Sciences, Discipline of Soil and Land Systems, 2005? / "August, 2004" Title from t.p. on PDF file; viewed 29 June 2005. Includes bibliographical references. Also available in a print form.

Thesis (M.S.)--University of Nevada, Reno, 2007. / "December 2007." Includes bibliographical references. Online version available on the World Wide Web.

Thesis (doctoral)--University of Tartu, 2004.

Thesis (M.S.)--Oregon State University, 2000. / Typescript (photocopy). Includes bibliographical references. Also available on the World Wide Web.

Thesis (M.S.)--Oregon State University, 1996. / Typescript (photocopy). Includes bibliographical references. Also available online.

Thesis (M.S.)--University of Kentucky, 2008. / Title from document title page (viewed on December 10, 2008). Document formatted into pages; contains: vii, 56 p. : ill. (some col.). Includes abstract and vita. Includes bibliographical references (p. 47-55).

Thesis (Ph. D.)--West Virginia University, 2006. / Title from document title page. Document formatted into pages; contains vii, 97 p. : ill. Includes abstract. Includes bibliographical references.

Arbuscular mycorrhizal (AM) fungi are a group of fungi that are able to establish a symbiotic relationship with the root system of many land plants. This symbiosis improves plant fitness by increasing the uptake of crucial mineral nutrients, particularly phosphorus and nitrogen. In return, the fungi receive organic carbon from the plant host in the form of sugars and lipids. The objective of my research is to assess whether the Nitrate and Peptide Transporter Family (NPF) of transport proteins play a role in mediating AM symbiosis. Firstly, we explored the involvement of NPF genes NPF1B and NPF4.12 by examining the phenotype of Medicago truncatula mutants. Secondly, we employed a modified yeast two-hybrid system to determine the phytohormone import capabilities of these NPF transport systems. Lastly, we employed reporter gene fusions to assess the spatial and temporal expression profiles of these NPF genes. The results of our research do not support our hypothesis that these NPF genes play a role in mediating AMF symbiosis. The results of the modified yeast-two hybrid tests revealed abscisic acid (ABA) and gibberellic acid (GA3) import capabilities of the transport system encoded by the gene NPF4.12. Future study of the diverse mechanisms that underpin AM symbiosis will nonetheless be useful to the agricultural industry by reducing farmer's reliance on chemical fertilizers.

Please read the abstract in the section, 00front, of this document / Thesis (PhD)--University of Pretoria, 2008. / Plant Science / unrestricted

Arbuscular mycorrhizal fungi (AMF) provide numerous services to their plant symbionts. Understanding the effects of climate change on AMF, and the resulting plant responses, is a crucial factor in predicting ecosystem responses on a global scale. We used a manipulative climate change experiment embedded within a natural climate gradient in Oregon and Washington to examine how the effects of future climate change on AMF-plant symbioses are mediated by soil water availability, soil nutrient availability, and vegetation dynamics. Using structural equation modeling, we found that the direct effect of increasing temperatures was to decrease AMF colonization. Indirect effects of temperature, mediated through other variables, canceled each other out. However, future shifts in these relationships could either exacerbate or mitigate the negative direct effect of temperature. As ecosystems in Mediterranean climates experience more intense droughts and heavier rains, decreases in AMF colonization could have substantial consequences for plant communities and ecosystem function.