Thesis (M.S.)--University of Tennessee, Knoxville, 2004. / Title from title page screen (viewed Sept. 23, 2004). Thesis advisor: Jerome F. Grant. Document formatted into pages (ix, 86 p. : ill. (some col.), col. maps). Vita. Includes bibliographical references (p. 76-85).

Thesis (M.A.)--University of Montana, 2007. / Title from title screen. Description based on contents viewed Aug. 17, 2007. Includes bibliographical references (p. 70-77).

Thesis (MS)--Montana State University--Bozeman, 2008. / Typescript. Chairperson, Graduate Committee: Jeffrey C. Mosley. Includes bibliographical references.

Thesis (M.S.)--Montana State University--Bozeman, 2005. / Typescript. Chairperson, Graduate Committee: Catherine A. Zabinski. Includes bibliographical references (leaves 68-74).

Thesis (MS)--Montana State University--Bozeman, 2008. / Typescript. Chairperson, Graduate Committee: Rodney W. Kott Includes bibliographical references.

Thesis (M.S.)--Montana State University, 2003. / Title from PDF title page (viewed Jan. 6, 2005). Includes bibliographical references (p. 56-63).

Thesis (Ph. D.)--University of Montana, 2007. / Title from title screen. Description based on contents viewed Oct. 9, 2008. Includes bibliographical references.

Spotted knapweed, Centaurea maculosa Lam. (Compositae) is an extremely successful introduced weed species in the northwestern United States. Multiple factors may be responsible for its success, including chemical defense. Two different types of putative chemical defense agents are the focus of this thesis. The first is a bitter-tasting sesquiterpene lactone, cnicin, which occurs at high concentrations in foliar tissues; the second is a group of polyacetylenic compounds produced in the roots. This study represents the first designation of structural identities to polyacetylenic compounds from North American populations of C. maculosa. Both cnicin and polyacetylenic compounds have demonstrated biological activity, suggesting roles in chemical defense. In order to test predictions of chemical defense hypotheses for this plant, concentrations of cnicin and polyacetylenes were measured in a greenhouse experiment in response to varying soil nitrogen and light availability. Light and soil nitrogen availability were important in determining concentrations and content of cnicin, whereas polyacetylene concentrations were not significantly affected by differences in these environmental parameters. Cnicin concentrations were also measured in a field experiment in response to varying levels of soil nitrogen and water. No significant differences in cnicin concentrations were observed among treatments in either young (rosette-stage) or mature aerial tissues. / Graduation date: 1999

Thesis (M.S.)--Montana State University--Bozeman, 2005. / Typescript. Chairperson, Graduate Committee: Jeffrey C. Mosley. Includes bibliographical references (leaves 525-59).

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