Thesis (Ph. D.)--University of Missouri-Columbia, 2007. / The entire dissertation/thesis text is included in the research.pdf file; the official abstract appears in the short.pdf file (which also appears in the research.pdf); a non-technical general description, or public abstract, appears in the public.pdf file. Title from title screen of research.pdf file (viewed on January 2, 2008) Includes bibliographical references.

Thesis (Ph.D.)--University of Illinois, 2009. / Vita. Includes bibliographical references.

Thesis (Ph.D.)--University of Missouri-Columbia, 2004. / Typescript. Vita. Includes bibliographical references (leaves 123-133). Also available on the Internet.

Thesis (Ph.D.)--University of Missouri-Columbia, 2004. / Typescript. Vita. Includes bibliographical references (leaves 123-133). Also available on the Internet.

Title from PDF of title page (University of Missouri--Columbia, viewed on Feb. 12, 2010 ). The entire thesis text is included in the research.pdf file; the official abstract appears in the short.pdf file; a non-technical public abstract appears in the public.pdf file. Dr. David A. Sleper, Thesis advisor Includes bibliographical references.

Thesis (Ph. D.)--University of Missouri-Columbia, 2000. / Typescript. Vita. Includes bibliographical references. Also available on the Internet.

Thesis (Ph. D.)--University of Missouri-Columbia, 2000. / Typescript. Vita. Includes bibliographical references. Also available on the Internet.

The initial interaction of vesicle and the target membrane prior to their fusion is called vesicle tethering, a process mediated by an octameric protein complex called the exocyst. The exocyst connects vesicles and binds them to phosphatidylinositol 4, 5-biphosphate (PI (4,5) P2), located on the plasma membrane. The exocyst complex is located at the target site, helping to prepare the soluble N-ethylmaleimide-sensitive fusion protein attachment protein (SNAP) receptor (SNARE) for docking and subsequent release of vesicular contents after fusion. The importance of the exocyst in cellular processes is inevitable since it performs central roles in exocytosis thereby inducing SNARE-mediated membrane fusion. The study presented here is concentrated on the role of exocyst genes during the defense response in Glycine max (soybean) against the plant- parasitic nematode Heterodera glycines known as the soybean cyst nematode (SCN). Using developmental genomics analysis, G. max root cells that have been induced by H. glycines through their pathogenic activities to develop into nurse cells known as a syncytium have been isolated by laser capture microdissection (LCM). RNA isolated from these cells undergoing resistant reactions in two different G. max genotypes have been used in gene expression profiling experiments that have led to the identification of the genes employed in this analysis. The results demonstrate the involvement of exocyst components in the defense process that G. max has toward H. glycines. Related studies also show the involvement of RPM1-INTERACTING PROTEIN 4 (RIN4) functioning in this defense process.

No description available.

Master of Science / Department of Agronomy / William T. Schapaugh Jr / The soybean cyst nematode (Heterodera glycines) (SCN) is an important pathogen of soybean in the United States. Annual yield losses from SCN are estimated to be over $2 billion worldwide. However, SCN virulence or the ability of a nematode to grow on resistant soybean genotypes varies widely among SCN populations. Fortunately there are several genetic sources of resistance to decrease the virulence of the pathogen on soybean. The objectives of this research were to: 1) characterize the genetic diversity of soybean cyst nematode populations in Kansas, 2) determine the frequency of Kansas SCN populations virulent on PI88788, 3) determine which plant introductions used in the HG Type Test provide the best level resistance, and 4) compare the performance of commercial soybean cultivars to the plant introduction from which their SCN resistance was derived. Soil samples were collected from SCN-infested fields across the state. Each soil sample was taken to the greenhouse and planted to a susceptible soybean cultivar to increase SCN population. Following an SCN population increase, a HG Type Test was planted. H. glycines field populations were highly variable, not only in population densities, but also in their abilities to develop on soybean genotypes. Collected from a diverse range of environments, ten HG types were identified. About 50% of the H. glycines populations were virulent on PI 88788, and most of the populations were virulent on commercial SCN resistant lines which derived their resistance from PI 88788. The commercial lines tended to be more susceptible to SCN than the lines from which they derived their resistance, but few HG populations were virulent on PI 437654 or the commercial line that derived its resistance from PI 437654. These results suggest that sources other than PI 88788 should be used in the development of H. glycines resistant cultivars for Kansas. One possible source of resistance is PI 437654. Information about SCN diversity in Kansas will improve decisions regarding cultivar development and selection for SCN management.