Botany Commons^™

Floral Trait Architecture In Crop Sunflower (Helianthus Annuus) Under Drought Conditions, Lauren Segarra

All Master's Theses

Longer and more intense droughts are predicted to become more common in the coming century due to anthropogenic climate change. Drought can reduce crop yield and decrease food security. In order to mitigate the negative effects of drought on crop production, it is important to elucidate the underlying mechanisms that promote drought stress resistance in crop plants. Floral traits impact yield, especially in oilseed crops such as sunflower (Helianthus annuus), but their susceptibility to drought stress is understudied. The goal of this study was to describe the floral trait architecture of H. annuus crop lines under drought versus …

Fire And Road Disturbance Impacts On Forest Plant Species And Seed Rain In Table Mountain Fire Arai, Kittitas County, Washington, Jonathan A. Betz

All Master's Theses

Forest communities are in a constant state of change. Disturbance events can alter the physical landscape and create conditions favorable to some species while negatively impacting others. Fire has been a natural, reoccurring source of disturbance in Pacific Northwest forests. Over the past centuries the fire paradigm has changed in favor of fire suppression. Forest roads permit access provide greater access but further fracture forest community’s continuity. The 2012 Table Mountain Fire and road influence have altered the plant community’s seed rain and vegetation. This study measured dispersed seeds and understory vegetation cover as functions of roads and fire intensity. …

Physiological Variation Of Garry Oak (Quercus Garryana) Seedlings To Drought Stress, Matthew A. Merz

All Master's Theses

The purpose of this study was to determine physiological differences in drought response among Garry oak (Quercus garryana Douglas ex Hook. [Fagaceae]) seedlings that grow in distinct populations in Washington state, in order to aid in restoration efforts by informing growers of the potential differences between the acorn collection sites. Acorns from six Washington populations east of the Cascades, as well as one population from Whidbey Island, were collected and grown in containers under controlled conditions. The plants were assessed with and without moderate and severe drought stress induced by withholding water. The most extreme differences in photosynthetic characteristics …

Antimicrobial And Antiinsectan Phenolic Metabolites Of Dalea Searlsiae, Gil Belofsky, Mario Aronica, Eric Foss, Jane Diamond, Felipe Santana, Jacob Darley, Patrick F. Dowd, Christina M. Coleman, Daneel Ferreira

All Faculty Scholarship for the College of the Sciences

Continued interest in the chemistry of Dalea spp. led to investigation of Dalea searlsiae, a plant native to areas of the western United States. Methanol extractions of D. searlsiae roots and subsequent chromatographic fractionation afforded the new prenylated and geranylated flavanones malheurans A–D (1–4) and known flavanones (5 and 6). Known rotenoids (7 and 8) and isoflavones (9 and 10) were isolated from aerial portions. Structure determination of pure compounds was accomplished primarily by extensive 1D- and 2D-NMR spectroscopy. The absolute configurations of compounds 1–5, 7 …

Effects Of Ultraviolet-B Radiation On Leaf Morphology Of Arabidopsis Thaliana (L.) Heynh. (Brassicaceae), Maria Regina Torres Boeger, Mary E. Poulson

Biology Faculty Scholarship

Reduction of the ozone layer results in the increase in ultraviolet radiation reaching the earth's surface, especially the ultraviolet-B (UV-B). The increase of radiation may induce structural and physiological changes in plants, influencing their growth and development. This paper evaluates the effects of ambient UV-B radiation upon to the leaf morphology of Arabidopsis thaliana developed under controlled conditions. The seeds of A. thaliana grown in environmental chamber, with 300 µmol m^-2s^-1 de photosynthetically active radiation (PAR) with and without 6 kJ m^-2 s^-1 of radiation UV-B_be (UV-B_be; UV-B biologically effective). After 21 …

Chloroplast Dna Rearrangements In Campanulaceae: Phylogenetic Utility Of Highly Rearranged Genomes, Mary E. Cosner, Linda A. Raubeson, Robert K. Jansen

All Faculty Scholarship for the College of the Sciences

Background

The Campanulaceae (the "hare bell" or "bellflower" family) is a derived angiosperm family comprised of about 600 species treated in 35 to 55 genera. Taxonomic treatments vary widely and little phylogenetic work has been done in the family. Gene order in the chloroplast genome usually varies little among vascular plants. However, chloroplast genomes of Campanulaceae represent an exception and phylogenetic analyses solely based on chloroplast rearrangement characters support a reasonably well-resolved tree.

Results

Chloroplast DNA physical maps were constructed for eighteen representatives of the family. So many gene order changes have occurred among the genomes that characterizing individual mutational …

The Riparian Vegetation Of Swauk Creek, Edward L. Schneider

All Master's Theses

An investigation was made to document the structure and composition of the flora along Swauk Creek, a riparian transect into Central Washington's Cascade Range. Distributions of the major species are discussed and a key has been constructed to facilitate identification of the riparian associations.