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Attack Of The Clones: Elucidating The Role Of Clonality In The Invasion Success Of Carpobrotus Edulis, Eduardo Luis Cruz

Electronic Theses, Projects, and Dissertations

Transcriptomics is a modern technique in genomics that utilizes RNA sequences to get a snapshot of genetic expression. This is a powerful tool in non-model species lacking a reference genome. Thus, the application of comparative transcriptomics has the potential to help us elucidate the evolutionary mechanisms that facilitate species invasion. Carpobrotus edulis is a prolific and widespread invasive succulent plant belonging to the Aizoaceae family. A native to South Africa, this species has become a dominant invader of many Mediterranean coastal areas. In this study, we leveraged the use of RNAseq to investigate evolutionary changes among invasive populations. RNA-seq data …

Warm Stratification Increases Germination Of Dendromecon Rigida And Ehrendorferia Chrysantha, Cesar Garcia

Electronic Theses, Projects, and Dissertations

We explored the seasonal factors that might play a role in triggering germination of Dendromecon rigidaand Ehrendorferia chrysantha.D. rigida and E. chrysantha have been found difficult to germinate using common greenhouse techniques, Keeley and Fotheringham successfully germinated both species after storing their seeds in the field over a year and treating them with smoke. Identifying the specific seasonally changing factors that stimulated germination could have implications for understanding germination requirements for these and other hard-to-germinate chaparral species.

Dendromecon rigidaand Ehrendorferia chrysanthaare part of the Papaveraceae family and both are found in the chaparral environment in …

Arsenic Analysis: Comparative Arsenic Groundwater Concentration In Relation To Soil And Vegetation, Rominna E. Valentine Vecorena

Electronic Theses, Projects, and Dissertations

Arsenic (As) is a toxic semi-metallic element found in groundwater, soils, and plants. Natural and anthropogenic sources contribute to the distribution of arsenic in the environment. Arsenic’s toxic and mobile behavior is associated with its speciation ability. There are two types of arsenic available to the environment, inorganic and organic arsenic. Of the two, inorganic arsenic is more toxic to humans and more mobile in the environment. Two inorganic compounds responsible for arsenic contamination are trivalent arsenite, As (III), and pentavalent arsenate, As (V). Trivalent arsenate is considered to be more soluble, toxic, and mobile than pentavalent arsenate. Arsenic’s absorptive …

Variation Between Peripheral And Center Achene Morphology And Attributes Of Achene Germination In The Invasive Species, Centaurea Melitensis, Kandee Bain

Electronic Theses, Projects, and Dissertations

Invasive species are often successful and problematic because of their ability to persist in disturbed and undisturbed environments despite weed management practices. Understanding reproduction and dispersal strategies in these species can aid in developing management approaches to help control their spread. Centaurea melitensis, a nonnative invasive with European origins, is found in disturbed areas of southern California. It produces three different types of flower heads that develop at different times and at different locations on the plant during the growing season. The chasmogamous (CH) flower heads are located at the top of the plant, the initial cleistogamous (iCL) heads …

A Review Of The Removal Of Arundo Donax From A Riparian Area Within San Timoteo Canyon, Catherine E. Howe

Electronic Theses, Projects, and Dissertations

A site within San Timoteo Canyon was revisited, 13-14 years after treatment, to look at long-term effects of Arundo donax removal. The data obtained were used to determine whether A. donax had re-invaded, other non-native species had established the area, or if native species were able to grow in place of the removed A. donax. The previous removals included a combination of grinding large patches of A. donax and then foliar spraying, foliar spraying of uncut plants, and direct spraying of hand cut stems, depending upon the location and size of the plant. The effects of the A. donax …