Open Access. Powered by Scholars. Published by Universities.®
- Discipline
- Keyword
- Publication
- Publication Type
- File Type
Articles 1 - 17 of 17
Full-Text Articles in Plant Sciences
Malosma Laurina Dieback Associated With Fungal Induced Loss In Hydraulic Conductivity And Photosynthesis, Gabriella N. Palmeri, Shaquetta R. Reese, Helen I. Holmlund, Frank W. Ewers, Stephen D. Davis
Malosma Laurina Dieback Associated With Fungal Induced Loss In Hydraulic Conductivity And Photosynthesis, Gabriella N. Palmeri, Shaquetta R. Reese, Helen I. Holmlund, Frank W. Ewers, Stephen D. Davis
Biology
Widespread Malosma laurina (Laurel Sumac) dieback is occurring throughout the Santa Monica Mountains. M. laurina is a keystone species within the SMM and its deep roots provide necessary slope stability to the hillsides; therefore, M. laurina’s health is of ecological importance. This study examines whether M. laurina dieback is associated with decreased stem water transport due to the prevalence of a pathogenic fungus within the water transport tissue. Stem samples from dieback and healthy control M. laurina were cultured for fungal growth. 100% of samples from water transport tissue from dieback adult plants contained a fungal pathogen from the …
Using Koch’S Postulate To Identify The Causative Agent Of Dieback In Malosma Laurina During Historic Drought In California, Adriana J. Borges, Emily R. Pierce, Mariah K. Taylor, Frida J. Morales
Using Koch’S Postulate To Identify The Causative Agent Of Dieback In Malosma Laurina During Historic Drought In California, Adriana J. Borges, Emily R. Pierce, Mariah K. Taylor, Frida J. Morales
Featured Research
Coastal Southern California has a Mediterranean-type climate, meaning that it experiences warm, dry summers and cool, wet winters. Recently, California has been experiencing an unprecedented drought, possibly as a result of climate change. Malosma laurina is a typically hearty chaparral plant is known for being resistant to drought due to its deep rooting depth, but even it is being negatively affected by drought and is experiencing dieback. Some of this dieback is caused by a Botryospharae fungal infection, which blocks xylem conduits and stops water flow through the plant. With a looming El Niño, this study seeks to understand the …
Using Koch’S Postulate To Identify The Causative Agent Of Dieback In Malosma Laurina During Historic Drought In California, Adriana J. Borges, Emily R. Pierce, Mariah K. Taylor, Frida J. Morales
Using Koch’S Postulate To Identify The Causative Agent Of Dieback In Malosma Laurina During Historic Drought In California, Adriana J. Borges, Emily R. Pierce, Mariah K. Taylor, Frida J. Morales
Featured Research
Coastal Southern California has a Mediterranean-type climate, meaning that it experiences warm, dry summers and cool, wet winters. Recently, California has been experiencing an unprecedented drought, possibly as a result of climate change. Malosma laurina is a typically hearty chaparral plant is known for being resistant to drought due to its deep rooting depth, but even it is being negatively affected by drought and is experiencing dieback. Some of this dieback is caused by a Botryospharae fungal infection, which blocks xylem conduits and stops water flow through the plant. With a looming El Niño, this study seeks to understand the …
The Effect Of Water Deficit On Photosynthetic Properties Of Salvia Leucophylla, Brianna Scott, Theadora Ordog, Alexis Lordi
The Effect Of Water Deficit On Photosynthetic Properties Of Salvia Leucophylla, Brianna Scott, Theadora Ordog, Alexis Lordi
Featured Research
California has been in a severe drought in recent years due to anthropogenic warming, and it has had a major effect on chemical and physical properties of native plants. Salvia leucophylla, a common plant in Southern California, has evolved an adaptation to water stress through losing its leaves, known as a drought deciduous plant. Considering the increase of CO2 in the atmosphere, it is absolutely essential for leaves to retain their ability to photosynthesize to maintain the health of the environment through CO2 sequestration. The objective of this experiment was to see how drought levels affect the physical and …
The Effect Of Temperature On Root Nodulation And Growth In Glycine Max, Brooke O’Neill, Katherine Kawachi
The Effect Of Temperature On Root Nodulation And Growth In Glycine Max, Brooke O’Neill, Katherine Kawachi
Featured Research
This investigation explores the effects of temperature on root nodulation and other plant growth factors in soy bean plants. Vegetative development such as node appearance rate increases as temperatures rise to the species’ optimum level, in which the maximum temperature for growth in C3 plants is 25 °C. (Hatfield, 2015). We hypothesized that soy bean plants would produce more nodules in 25°C than 35°C, rationalizing the Q10 theory which states that a 10 degree temperature change produces measureable effects in biological and chemical metabolic systems. This idea becomes worthy of experiment when looking at how increasing temperature affects …
Comparison Of Nighttime Stomatal Conductance In Malosma Laurnia And Encelia Californica, Stephanie R. Kaplan, Jessica T. Gash, Hannah H. Ziegler
Comparison Of Nighttime Stomatal Conductance In Malosma Laurnia And Encelia Californica, Stephanie R. Kaplan, Jessica T. Gash, Hannah H. Ziegler
Featured Research
The experiment aimed to look at the comparison between the nighttime stomatal conductance of Malosma laurina and Encelia californica. Through the use of leaf porometry and subsequent data analysis, it was determined that there was no statistical differnce between either species, due to the fact that the Malosma laurina was a resprouted species, that needed significantly less water than a fully mature M. laurina plant would have needed.
The Effect Of The Tapia Water Treatment Plant On The Growth Of Lemna Minor, Morgan Clark, Imani Goodman, William Ota, Alora Yarbrough
The Effect Of The Tapia Water Treatment Plant On The Growth Of Lemna Minor, Morgan Clark, Imani Goodman, William Ota, Alora Yarbrough
Featured Research
Human beings are changing not just global temperature but even the makeup of the water in our planet's rivers and streams. The Tapia Water Treatment Facility is located in the upper section of Malibu creek and treats around 9.5 million gallons per day of water which is then released into the Malibu watershed. This water is treated using chemicals not typically found in local streams and these chemicals may be harming the organisms that live downstream of the water treatment plant. Downstream from the Tapia water treatment plant we were able to find increased levels of both nitrates and phosphates …
Comparing The Electron Transport Rate Of Nico%Ana Glauca And Encelia Californica At Normal And Increased Par, Carter Clinebell, Griffin Duvall, Daniel Suh
Comparing The Electron Transport Rate Of Nico%Ana Glauca And Encelia Californica At Normal And Increased Par, Carter Clinebell, Griffin Duvall, Daniel Suh
Featured Research
The purpose of this experiment is to investigate how normal and increased sunlight affects both indigenous and non-native species in Southern California’s chaparral ecosystem. Encelia californica and Nicotiana glauca were chosen as representative native and invasive species respectively. The electron transport rate (ETR) of the two species are expected to be higher at 2400 PAR (photosynthetic active radiation) than at 2000 PAR. The ETR between the two species is also expected to be different. The difference between species is important for understanding the advantages and disadvantages of species dependent on sunlight exposure. The ETR was measured using a Li-Cor 6400 …
Allelopathic Compounds In Adenostoma Fasciculatum Leaves May Inhibit Seed Germination Of Ceanothus Megacarpus, Olivia L. Le Sage, Shamiran C. Prater, Christian M. Botello
Allelopathic Compounds In Adenostoma Fasciculatum Leaves May Inhibit Seed Germination Of Ceanothus Megacarpus, Olivia L. Le Sage, Shamiran C. Prater, Christian M. Botello
Featured Research
We investigated the effects the allelopathogen thought to be found in Adenostoma fasciculatum leaves on seed germination in Ceanothus megacarpus seeds. We hypothesized that seeds treated with an extract containing the allelopathogen would not germinate, compared to seeds not treated with the allelopathogen. We hypothesized this because Adenostoma fasciculatum is known to produce an allelopathogen which inhibits growth in nearby plants in a natural environment. We prepared a 70% ethanol extract with Adenostoma fasciculatum leaves and treated 30 scarified Ceanothus megacarpus seeds with it; 30 additional Ceanothus megacarpus seeds were only given 70% ethanol. We placed these seeds in a …
Root Hydraulic Conductance In Laurel Sumac Experiencing Severe Dieback In The Santa Monica Mountains, Natalie M. Aguirre, Avery N. Davis, Sarah B. Nelson, Stephen D. Davis
Root Hydraulic Conductance In Laurel Sumac Experiencing Severe Dieback In The Santa Monica Mountains, Natalie M. Aguirre, Avery N. Davis, Sarah B. Nelson, Stephen D. Davis
Featured Research
Malosma laurina (laurel sumac) is a dominant species in coastal chaparral ecosystems, extending its roots down to an average of 40 feet in rocky, sandy soils. The deep root systems of M. laurina provide structural support for the steep Santa Monica Mountains. The roots also allow M. laurina to draw from the deep water table, increasing its drought tolerance. M. laurina dieback is prevalent in coastal exposures of the Santa Monica Mountains presumably due to historic drought predisposing plant tissues to infection by the fungal pathogen Botryosphaeria dothidea. In ecosystems that experience annual dry periods, a high hydraulic conductance …
Effects Of Drought On Antimicrobial Properties Of A Chaparral Indicator Species — Adenostoma Fasciculatum, Andrew Shute, Jennifer Duff, Salina Pearce-Harris
Effects Of Drought On Antimicrobial Properties Of A Chaparral Indicator Species — Adenostoma Fasciculatum, Andrew Shute, Jennifer Duff, Salina Pearce-Harris
Featured Research
The dominant plant type of Pepperdine’s Malibu campus is chaparral, of which an important indicator species is Adenostoma fasciculatum. It is known that A. fasciculatum produces compounds that are deadly to many bacteria. However, California is currently experiencing unprecedented drought, which is pushing plants well beyond their normal stress levels. In this study, we investigated the effect of drought stress on the ability of A. fasciculatum to inhibit growth of bacteria. We hypothesized that extract from drought-stressed plants would be better able to kill bacteria than hydrated ones, because the plant would be induced to produce more antimicrobial compounds …
Extensive Dieback In Malosma Laurina In Coastal Exposures Of The Santa Monica Mountains Associated With Unprecedented Drought In California, Gina S. Gilderman, Kaitlyn E. Sauer, Gabriella N. Palmeri
Extensive Dieback In Malosma Laurina In Coastal Exposures Of The Santa Monica Mountains Associated With Unprecedented Drought In California, Gina S. Gilderman, Kaitlyn E. Sauer, Gabriella N. Palmeri
Featured Research
Throughout coastal exposures of the Santa Monica Mountains (SMM) there is a recent emergence of widespread dieback in Laurel Sumac (Malosma laurina). M. laurina is a keystone species of chaparral that dominates the SMM. A significant trait of M. laurina is an extensive root system exceeding 12 m in depth. We hypothesized that M. laurina was weakened by unprecedented drought in California (2013-2015) and predisposed to fungal pathogens. An initial study conducted in the summer of 2015 revealed all stem samples taken from dieback adult M. laurina plants were infected with Botryosphaeria dothidea, while zero stem samples taken …
The Effects Of Human Involvement: A Study Of Transplanted Nassella Pulchra In A Competitive Environment, Miranda Prints, Summer Ngo, Taylor Purdy
The Effects Of Human Involvement: A Study Of Transplanted Nassella Pulchra In A Competitive Environment, Miranda Prints, Summer Ngo, Taylor Purdy
Featured Research
When construction began on the Drescher Graduate Campus, the need to preserve a rare native California grass saw the creation of a transplant garden. A perennial bunchgrass, Nassella pulchra (purple needlegrass), was replanted. Based on a hypothesis that Avena fatua (wild oats), a competitor, would have a greater health than the native grass Nassella pulchra, we measured stomatal conductance, fluorescence, evident fitness, and water potential. In our second hypothesis, we proposed that the naturally occurring Nassella pulchra would have a higher stomatal conductance, a higher fluorescence, a higher water potential, and overall higher fitness than the transplanted …
Extensive Dieback In Malosma Laurina In Coastal Exposures Of The Santa Monica Mountains Associated With Unprecedented Drought In California, Gina S. Gilderman, Kaitlyn E. Sauer, Gabriella N. Palmeri
Extensive Dieback In Malosma Laurina In Coastal Exposures Of The Santa Monica Mountains Associated With Unprecedented Drought In California, Gina S. Gilderman, Kaitlyn E. Sauer, Gabriella N. Palmeri
Featured Research
Throughout coastal exposures of the Santa Monica Mountains (SMM) there is a recent emergence of widespread dieback in Laurel Sumac (Malosma laurina). M. laurina is a keystone species of chaparral that dominates the SMM. A significant trait of M. laurina is an extensive root system exceeding 12 m in depth. We hypothesized that M. laurina was weakened by unprecedented drought in California (2013-2015) and predisposed to fungal pathogens. An initial study conducted in the summer of 2015 revealed all stem samples taken from dieback adult M. laurina plants were infected with Botryosphaeria dothidea, while zero stem samples taken …
Botryosphaeria Dothidea Impacts Relative Water Abundance In Malosma Laurina, Andrew Lozano, Michael Gribble, Jared Delapaz
Botryosphaeria Dothidea Impacts Relative Water Abundance In Malosma Laurina, Andrew Lozano, Michael Gribble, Jared Delapaz
Featured Research
Over the past decade, the California drought has been affecting native chaparral in the Santa Monica Mountains. Some parasitic fungi species such as Botryosphaeria dothidea have taken advantage of the drought by invading open wounds, or cankers, in a plant. When extreme environmental stress such as drought occurs, the immune system of the plant is compromised; the fungus can then multiply within the plant, blocking the vascular tissue. In this study, we aim to determine if there is a relationship between the presence of B. dothidea and an increase in the flammability of the native chaparral species Malosma laurina. …
Nodes Alter Stem Mechanical Strength In Heteromeles Arbutifolia, Gabriella E. Chan, Caleigh A. Howard, Callie E. Shelley
Nodes Alter Stem Mechanical Strength In Heteromeles Arbutifolia, Gabriella E. Chan, Caleigh A. Howard, Callie E. Shelley
Featured Research
Our thesis was that the presence of nodes in stems of Heteromeles arbutifolia plants would increase the mechanical strength of the xylem and the bark, allowing the stems to be better protected against harsh weather conditions during the severe California drought. We conducted research on two sample groups, one with nodes and one without nodes. An Instron machine tested the mechanical strength by bending the stems until the xylem broke. Values for MOR (modulus of rupture) and MOE (modulus of elasticity) were measured to determine the overall strength of both groups. We found that the xylem of the stems was …
Root Hydraulic Conductance In Malosma Laurina Experiencing Severe Dieback In The Santa Monica Mountains, Natalie M. Aguirre 5861995, Avery Davis, Sarah Nelson
Root Hydraulic Conductance In Malosma Laurina Experiencing Severe Dieback In The Santa Monica Mountains, Natalie M. Aguirre 5861995, Avery Davis, Sarah Nelson
Seaver College Research And Scholarly Achievement Symposium
Malosma laurina is a dominant species in coastal chaparral ecosystems The deep root systems of M. laurina provide structural support for the steep Santa Monica Mountains and allow M. laurina to tap into the deep water table. M. laurina dieback is prevalent in coastal exposures of the SMM, presumably due to historic drought predisposing plant tissues to infection by the fungal pathogen Botryosphaeria dothidea. In ecosystems that experience annual dry periods, a high hydraulic conductance in roots is necessary to provide plants with sufficient water. A recent study has examined the effect of Botryosphaeria on the hydraulic conductance of M. …