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Investigating The Molecular Basis Of Volatile-Mediated Plant Indirect Defense Against Herbivorous Insects Using Functional And Comparative Genomics, Shuhua Yuan

Doctoral Dissertations

Volatile organic compounds (VOCs) play important roles in plant indirect defense against herbivorous insects by attracting the natural enemies. I first used a tritrophic model system involving rice, rice fall armyworm (Spodoptera frugiperda), and the parasitoid Cotesia marginiventris to discover and characterize the volatile terpenoids and TPS genes involved in the indirect defense of rice against the insect herbivory with integrated functional genomics analyses. Seven rice TPS genes were found to be significantly up-regulated by both microarray and real-time PCR analyses, with one characterized as a linalool synthase and two as sesquiterpene synthases. The products of all three …

Bryoecology Of The Appalachian Spruce-Fir Zone, Daniel Howard Norris

Doctoral Dissertations

Introduction: Ecological investigation of an area ordinarily follows a certain course. First explorations attempt to discover the nature of the flora, and ecological information is incidental to the habitat notes of collected species. Later, general qualitative observations appear regarding he vegetation of particular habitats. Only after this is a quantitative study using quadrats or other sampling techniques begun, and this quantitative work lays the foundation for future autecological, ecosystem and productivity work. Traditionally the above course is followed first by workers in vascular plant ecology, and studies of cryptograms are seldom as far advanced as that of the spermatophytes.

The …

Ground Vegetation Patterns Of The Spruce-Fir Area Of The Great Smoky Mountains National Park, Dorothy Louise Crandall

Doctoral Dissertations

Introduction: Although the spruce-fir area of the Southern Appalachians has interested several investigators, there have been few studies of the herbaceous plants in relation to the canopy and none with this relationship as the primary objective. Ecological surveys have been made by Cain (1931, 1935), Oosting and Billings (1951), and Whittaker (1956), but their papers do not report details in reference to site types and include rather limited material on the ground cover. Possible site types were mentioned by Whittaker but were not described and few supporting data of an objective nature were included.

Cain in his 1935 paper on …