Plant Biology Commons^™

Response Of Nebraska Horseweed (Conyza Canadensis) Populations To Dicamba, Roberto Crespo, Mark L. Bernards, Greg Kruger, Donald Lee, Robert Wilson Jr.

Department of Agronomy and Horticulture: Dissertations, Theses, and Student Research

Dicamba-resistant soybeans are being developed to provide an additional herbicide mechanism-of-action for postemergence weed control in soybean. Numerous broadleaf species, including horseweed, have evolved resistance to glyphosate. It is anticipated that dicamba will be used by farmers as a primary tool to manage these weeds. Studying and understanding variability in horseweed response to dicamba will aid in developing appropriate risk management strategies to extend the utility of the dicamba-resistance technology. Horseweed plants from ten Nebraska populations were treated with one of nine doses of dicamba in greenhouse experiments. At 28 days after treatment (DAT) visual injury estimations were made and …

Using The Unispec To Test The Difference In Reflectance Of The Yellow Petals Of Encelia Californica, Encelia Farinosa, And Spartium Junceum, Mariam E. Fam, Valerie E. Espinoza

Featured Research

The reflectance spectrum of three yellow flowered species (Encelia californica, Encelia farinosa, and Spartium junceum), all grown on the coast of California, was tested to determine if reflectance among the yellow flowers was significantly different. It was hypothesized that there would be a significant difference in reflectance in the 400-700 nm wavebands for the three different species of flowers which all possess yellow petals. Using a Unispec Spectral Analysis System to obtain reflectance spectra for 12 yellow petals of three flowered species, a custom index was created in order to observe differences in the yellow color of the petals, which …

The Effects Of Leaf Hydration On Light Reflectance In Salvia Leucophylla And S. Mellifera, Logan A. Schmitz, Kolina Mah-Ginn, Hayley Presthus

Featured Research

The presence of trichomes on a plant affect the plant’s ability to retain water; this, in turn, must affect light propagation and reflectance. It was hypothesized that a plant with a higher trichome density (Salvia leucophylla) would have a greater change in reflectance when exposed to a more aired or hydrated environment than a species with a lower trichome density (S. mellifera). Results obtained using a Unispec suggest that Salvia mellifera is more resistant to change in NDVI in response to drying and wetting. Water potential data suggest this may be related to the plant’s resistance to actual drying and …

Fire Edge Effect On Water Potential And Stomatal Conductance In Salvia Leucophylla, Brigid N. Bergin, Paul Chung, Laura C. Miranda

Featured Research

While most plants caught in the middle of wildfires are completely incinerated, many in the edges survive despite suffering partial incineration and/or heat-induced damage. We hypothesized that heat damaged Salvia leucophylla will display a decrease in both stomatal conductance and water potential. We suspected that applying excess heat would lower the plant’s water levels and damage functional components necessary for photosynthesis, so the stomata would close to conserve water. S. leucophylla was chosen to study due to the likelihood of this widespread coastal sage to be found in the edges of wildfires in the Santa Monica Mountains. Using a heat …

Comparative Study Of The Mechanical Strength In Two Species Of Ferns: Polystichum Munitum And Pteridium Aquilinum, Russell P. Baetiong, Victoria M. Lekson, Olivier B. Monty

Featured Research

A comparative study of the mechanical strength in two species of ferns, the winter deciduous Pteridium aquilinum and the evergreen Polystichum munitum, was done. The mechanical strength of the leaf and stipe were used as a means for comparison. Additional data such as specific leaf mass (g/cm2) were also collected. The first hypothesis was that the evergreen fern would have higher leaf mechanical strength, while the second hypothesis was that there would be no difference in the mechanical strength of the stipe. The mechanical strength of the stipe was compared through the Modulus of Elasticity (MOE), while the leaf tensile …

Top And Bottom Photosynthetic Activity In Nerium Oleander And Pandanus Baptistii, Ryan Arima, Jacob Gonzalez

Featured Research

Photosynthesis can be performed on any part of a leaf, yet many plants orient their leaves in different ways and are composed of different leaf anatomies. In this experiment we attempted to discover if there is a significant difference between photosynthesis on the top and bottom of Nerium oleander, a dicot that orients its dorsal face towards the sun, and Pandanus baptistii, a monocot that does not orient its leaves specifically to the sun. To perform this experiment, we used both the LI-6400 and the LiCor Integrating Sphere. With the LI-6400, we measured the photosynthetic rate of the top and …

Mechanical Strength Comparison Of Hydrated And Dehydrated Pteridium Stems, Michelle I. Kang, Kevin M. Ko, John H. Noh, Veronica R. Vega

Featured Research

In this experiment, the mechanical strength of Pteridium stems was tested in two differing conditions: hydrated and dehydrated. It was hypothesized that there would be an increased performance of hydrated stems in the presence of mechanical stress. In order to test this hypothesis, twelve 20 cm pieces of stems were cut in alternation, separating those that would be dehydrated (6) with those that were hydrated (6). The dehydrated specimens were left to dry over a period of 24 hours. The diameters of each individual stem were measured to account for variation in size and remove excess variables. All twelve stems …

Neofusicoccum Luteum As A Pathogen On Tejocote (Crataegus Mexicana), Anthony O. Adesemoye, Joey S. Mayorquin, Akif Eskalen

Department of Plant Pathology: Faculty Publications

Tejocote (Crataegus mexicana), a small pome crab-apple-like fruit, is becoming economically important in California with increasing production, so consideration of diseases that hinder the yield is important. Diseased trees of tejocote were observed in four orchards of Riverside and San Diego Counties of California. Ten symptomatic/asymptomatic samples were studied from each of the orchards. Five most frequently isolated fungi were identified on the basis of morphological characters and sequence data of the internal transcribed spacer ITS1-5.8SITS2 and partial β-tubulin gene. Three isolates were identified as Neofusicoccum luteum and two as Phomopsis sp. Pathogenicity tests were conducted by inoculating …

Anti-Helicobacter Pylori Activity And Inhibition Of Helicobacter Pylori-Induced Release Of Il-8 In Ags Cells By Plant Extracts, Javed Yakoob, Zaigham Abbas, Rustam Khan, Muhammad Waqas Usman, Saeed Hamid, Safia Awan, Kanza Shamim, Syed Faisal Zaidi, Toshiro Sugiyama, Wasim Jafri

Section of Gastroenterology

Plants used in popular diet were studied for anti-Helicobacter pylori activity and their effect on the expression of interleukin-8 (IL-8) from H. pylori infected gastric epithelial cells. Extracts were prepared of Allium sativum (A. sativum), Cuminum cyminum (C. cyminum),Piper nigrum (P. nigrum) and their mix in two different dilutions. AGS cell line and H. pyloristrains were used for co-culture experiments. Extracts bactericidal activity was determined by a viable colony count. ELISA (Enzyme linked immunosorbent assay) was used to determine IL-8 expression. DNA extracted from bacterial cells was used for polymerase chain reaction (PCR) …

Environmental And Physiological Influences On Productivity And Carbon Isotope Discrimination In Eelgrass (Zostera Marina L.), Meredith Leigh Mcpherson

OES Theses and Dissertations

A short-term longitudinal study was used to examine the relations of achievement motivation, general motivation, interest, and self-regulatory predictors to cognitive strategy use and academic performance. A total of 102 college undergraduates enrolled in their first college-level introductory psychology course completed an Achieving Tendency Scale of achievement motivation, the Motivated Strategies For Learning Questionnaire, and an Interest Profile in psychology during the first two weeks of the semester. At midterm they completed the Study Activity Survey of cognitive strategy use. At the end of the semester exam grades, total points earned in the course, and grade point average were obtained. …

Survey Of Suitable Plants For Cal Poly's Green Wall, Katrina Burritt

Horticulture and Crop Science

Green wall technology is a growing industry in the United States and has been very successful for a several years throughout Europe. The objective of this survey was to study the success of several different species of plants on a vertical wall facing south at Cal Poly’s Horticultural Department Unit. At first the focus was aimed at using California native species, because it was thought that natives would be better acclimated to the exposure in this specific location. It became apparent that plants should not be selected for the wall based just on the fact that they are California natives. …

Pseudomonas Hopu1 Modulates Plant Immune Receptor Levels By Blocking The Interaction Of Their Mrnas With Grp7, Valerie Nicaise, Anna Joe, Byeong-Ryool Jeong, Christin Korneli, Freddy Boutrot, Isa Westedt, Dorothee Staiger, James R. Alfano, Cyril Zipfel

Center for Plant Science Innovation: Faculty Publications

Pathogens target important components of host immunity to cause disease. The Pseudomonas syringae type III-secreted effector HopU1 is a mono-ADP-ribosyltransferase required for full virulence on Arabidopsis thaliana. HopU1 targets several RNA-binding proteins including GRP7, whose role in immunity is still unclear. Here, we show that GRP7 associates with translational components, as well as with the pattern recognition receptors FLS2 and EFR. Moreover, GRP7 binds specifically FLS2 and EFR transcripts in vivo through its RNA recognition motif. HopU1 does not affect the protein–protein associations between GRP7, FLS2 and translational components. Instead, HopU1 blocks the interaction between GRP7 and FLS2 and …

Small Interfering Rna–Mediated Translation Repression Alters Ribosome Sensitivity To Inhibition By Cycloheximide In Chlamydomonas Reinhardtii, Xinrong Ma, Eun-Jeong Kim, Insun Kook, Fangrui Ma, Adam Voshall, Etsuko N. Moriyama, Heriberto D. Cerutti

Center for Plant Science Innovation: Faculty Publications

Small RNAs (sRNAs; approximately 20 to 30 nucleotides in length) play important roles in gene regulation as well as in defense responses against transposons and viruses in eukaryotes. Their biogenesis and modes of action have attracted great attention in recent years. However, many aspects of sRNA function, such as the mechanism(s) of translation repression at postinitiation steps, remain poorly characterized. In the unicellular green alga Chlamydomonas reinhardtii, sRNAs derived from genomeintegrated inverted repeat transgenes, perfectly complementary to the 39 untranslated region of a target transcript, can inhibit protein synthesis without or with only minimal mRNA destabilization. Here, we report …

Strong Genetic Differentiation Between North American And European Populations Of Phytophthora Alni Subsp. Uniformis, Jaime Aguayo, Gerard C. Adams, Fabien Halkett, Mursel Catal, Claude Husson, Zoltán Á. Nagy, Everett M. Hansen, Benoît Marçais, Pascal Frey

Department of Plant Pathology: Faculty Publications

Alder decline caused by Phytophthora alni has been one of the most important diseases of natural ecosystems in Europe during the last 20 years. The emergence of P. alni subsp. alni—the pathogen responsible for the epidemic—is linked to an interspecific hybridization event between two parental species: P. alni subsp. multiformis and P. alni subsp. uniformis. One of the parental species, P. alni subsp. uniformis, has been isolated in several European countries and, recently, in North America. The objective of this work was to assess the level of genetic diversity, the population genetic structure, and the putative reproduction …

Distance And Sex Determine Host Plant Choice By Herbivorous Beetles, Daniel J. Ballhorn, Stefanie Kautz, Martin Heil

Biology Faculty Publications and Presentations

Background: Plants respond to herbivore damage with the release of volatile organic compounds (VOCs). This indirect defense can cause ecological costs when herbivores themselves use VOCs as cues to localize suitable host plants. Can VOCs reliably indicate food plant quality to herbivores?

Methodology: We determined the choice behavior of herbivorous beetles (Chrysomelidae: Gynandrobrotica guerreroensis and Cerotoma ruficornis) when facing lima bean plants (Fabaceae: Phaseolus lunatus) with different cyanogenic potential, which is an important constitutive direct defense. Expression of inducible indirect defenses was experimentally manipulated by jasmonic acid treatment at different concentrations. The long-distance responses of male and female beetles to …

Isolation And Characterization Of The Grain Mold Fungi Cochliobolus And Alternaria Spp. From Sorghum Using Semiselective Media And Dna Sequence Analyses, Deanna L. Funnell-Harris, Louis K. Prom, Jeffrey F. Pedersen

Department of Plant Pathology: Faculty Publications

Mold diseases, caused by fungal complexes including Alternaria, Cochliobolus, and Fusarium species, limit sorghum grain production. Media were tested by plating Fusarium thapsinum, Alternaria sp., and Curvularia lunata, individually and competitively. Dichloran chloramphenicol rose bengal (DRBC) and modified V8 juice (ModV8) agars, found to be useful, were compared with commonly used agar media, dichloran chloramphenicol peptone (DCPA) and pentachloronitrobenzene (PCNB). Radial growth, starting with mycelia or single-conidia and hyphal tips, demonstrated an effect of media. For isolation of grain fungi, DRBC and ModV8 were similar or superior to DCPA and PCNB. When seedlings were inoculated with conidia of C. lunata, …

Occurrence And Distribution Of Triticum Mosaic Virus In The Central Great Plains, E. Byamukama, D. L. Seifers, G. L. Hein, E. De Wolf, N. A. Tisserat, M. A. C. Langham, L. E. Osborne, A. Timmerman, S. N. Wegulo

Department of Plant Pathology: Faculty Publications

Wheat curl mite (WCM)-transmitted viruses—namely, Wheat streak mosaic virus (WSMV), Triticum mosaic virus (TriMV), and the High Plains virus (HPV)—are three of the wheat-infecting viruses in the central Great Plains of the United States. TriMV is newly discovered and its prevalence and incidence are largely unknown. Field surveys were carried out in Colorado, Kansas, Nebraska, and South Dakota in spring and fall 2010 and 2011 to determine TriMV prevalence and incidence and the frequency of TriMV co-infection with WSMV or HPV in winter wheat. WSMV was the most prevalent and was detected in 83% of 185 season–counties (= s-counties), 73% …

Chapter 6 - Technological And Commercial, Janice M. Glime

Bryophyte Ecology Volume 5: Uses

Explore the contents of Bryophyte Ecology, Volume 5, Chapter 6 - Technological and Commercial by clicking the link above. For the Contents section of this ebook, as well as Volumes 1 through 5, please visit the Bryophyte Ecology Main Page.

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Ebook sponsored by Michigan Technological University and the International Association of Bryologists.

Chapter 2 - Medicine, Janice M. Glime

Bryophyte Ecology Volume 5: Uses

Explore the contents of Bryophyte Ecology, Volume 5, Chapter 2 - Medicine by clicking the link above. For the Contents section of this ebook, as well as Volumes 1 through 5, please visit the Bryophyte Ecology Main Page.

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Ebook sponsored by Michigan Technological University and the International Association of Bryologists.

Chapter 2 - Laboratory Techniques, Janice M. Glime, David H. Wagner

Bryophyte Ecology Volume 3: Methods

Explore the contents of Bryophyte Ecology, Volume 3, Chapter 2 - Laboratory Techniques by clicking the links above. For the Contents section of this ebook, as well as Volumes 2 through 5, please visit the Bryophyte Ecology Main Page.

Use CTRL+F to easily search within PDF files.

Ebook sponsored by Michigan Technological University and the International Association of Bryologists.