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Full-Text Articles in Life Sciences
The Rate Of Fungal Pathogen Growth (Botryosphaeria Dothidea) In Stems Of The Chaparral Shrub Rhus Integrifolia, Jayla D. Simmons, Edward J. Ayala, Kamara J. Satcher, Stephen D. Davis, Karagan L. Smith, Talia A. Cao
The Rate Of Fungal Pathogen Growth (Botryosphaeria Dothidea) In Stems Of The Chaparral Shrub Rhus Integrifolia, Jayla D. Simmons, Edward J. Ayala, Kamara J. Satcher, Stephen D. Davis, Karagan L. Smith, Talia A. Cao
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The fungus Botryosphaeria dothidea will grow between one to five millimeters after a week on the chaparral species Rhus integrifolia. To test this, we inoculated six individual shrub located behind the greenhouse on Campus Walk Road . On each shrub we selected two branches, receiving adequate and equal sunlight and inoculated one branch with the fungus B. dothidea and the other with a plain gel in order to compare the growth with a control group. The data we collected at the end of the one week period was similar to our initial hypothesis. The shortest growth was on the …
Post-Drought Recovery In The Chaparral Shrub Ceanothus Spinosus, Katie C. Lindley, Kylie N. Smith, Nina R. Duchild, Stephen D. Davis, Karagan L. Smith, Talia A. Cao
Post-Drought Recovery In The Chaparral Shrub Ceanothus Spinosus, Katie C. Lindley, Kylie N. Smith, Nina R. Duchild, Stephen D. Davis, Karagan L. Smith, Talia A. Cao
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This study investigated the abilities of Ceanothus spinosus, or greenbark ceanothus, to recover after a historic drought. This plant is one of the hardiest in the Santa Monica Mountains, providing soil stabilization and nutrients to other organisms in the ecosystem. In a previous investigation done during the drought, it was found that C. spinosus subjects growing in their natural habitat experienced significant dieback, with predawn water potentials falling as low as -7 MPa and native embolisms at an average of 47.17% (Ross et al., 2016). Other parameters tested were stomatal conductance, photosynthetic rate, and chlorophyll fluorescence. Compared to the …
Comparison Of Photosynthesis Among Three Chaparral Species In The Family Anacardiaceae, Catelyn T. Price, Sarah A. Holmes, Brandon T. Harris, Stephen D. Davis, Karagan L. Smith, Talia A. Cao
Comparison Of Photosynthesis Among Three Chaparral Species In The Family Anacardiaceae, Catelyn T. Price, Sarah A. Holmes, Brandon T. Harris, Stephen D. Davis, Karagan L. Smith, Talia A. Cao
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Recent argumentative data showed a lack of niche differentiation amongst three Banksia species in Australia conducted by Lamont and Bergl, and the Anacardiaceae family in the native chaparral of the Santa Monica Mountains are supposed to be significantly similar1. Because of this we wanted to test if there would be a significant difference between the stomatal conductance, photosynthesis, and water potential in samples of the Rhus ovata, Rhus integrifolia, and Malosma laurina (Rhus laurina) species. We tested this idea by collecting the stomatal conductance and photosynthetic rates of each plant species in the same general location with …
Testing For The Presence Of Botryosphaeria Dothidea In Ceanothus Spinosus, Brandon R. Grinovich, Chelsea N. Puncochar, Katarina L. Carter, Stephen D. Davis, Rodney L. Honeycutt, Talia A. Cao, Karagan L. Smith
Testing For The Presence Of Botryosphaeria Dothidea In Ceanothus Spinosus, Brandon R. Grinovich, Chelsea N. Puncochar, Katarina L. Carter, Stephen D. Davis, Rodney L. Honeycutt, Talia A. Cao, Karagan L. Smith
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Botryosphaeria dothidea is an opportunistic fungus found in some of the cavitated branches of the vegetation in the Santa Monica Mountains. In this study, we focused on finding the presence of Botryosphaeria dothidea in Ceanothus spinosus located on Pepperdine University’s campus. We wanted to test this hypothesis because we observed a large amount of dieback in the Ceanothus spinosus population and wanted to identify a possible contributor. Because of the large number of cavitated branches the Ceanothus spinosus contained, we hypothesized they contained fungus. To test this, we took twenty samples of twenty different Ceanothus spinosus, isolated the fungus …
Potential Recovery From Drought-Induced Dieback In A Keystone Chaparral Species, Malosma Laurina, Guinevere X. Mesh, Natalie M. Aguirre, Stephen D. Davis
Potential Recovery From Drought-Induced Dieback In A Keystone Chaparral Species, Malosma Laurina, Guinevere X. Mesh, Natalie M. Aguirre, Stephen D. Davis
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After five years of protracted drought and water-related dieback and mortality, the coastal chaparral ecosystems of the Santa Monica Mountains have finally received increased precipitation. As a co-dominant plant species in this region, Malosma laurina (common name Laurel Sumac), provides an important indication of environmental change. This study examines the effect of the increased precipitation of the 2016-2017 rainy season on potential recovery from drought-induced dieback in M. laurina. This study shows a significant increase in tissue hydration levels and photosynthetic production of dieback plants during post-drought recovery (2017) and between irrigated control sites and dieback sites.
Comparative Fitness Of Transplanted Nassella Pulchra: A Study Of Native And Invasive Grasses, Grace Palmer, Yash Pandey, Isabelle Panos
Comparative Fitness Of Transplanted Nassella Pulchra: A Study Of Native And Invasive Grasses, Grace Palmer, Yash Pandey, Isabelle Panos
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Previous study of the fitness of California, perennial N. pulchra was conducted at the transplant garden on the Drescher campus of Pepperdine University in the spring of 2016. A follow up study was conducted to understand how the recent increase in rainfall has affected the comparative health of N. pulchra in the transplant garden and in the wild, as well as the health of the invasive, annual grass A. fatua. The height, water potential, photoprotection, and stomatal conductance were measured in transplant N. pulchra, wild N. pulchra, and the competing A. fatua. It was hypothesized that A. fatua …
A Comparative Study Of Adults Vs. Resprouts’ Stomatal Conductance And Xylem Water Potential In Malosma Laurina, Lauren Dam, Brinna Lee, Sarah Dahlberg, Stephen Davis
A Comparative Study Of Adults Vs. Resprouts’ Stomatal Conductance And Xylem Water Potential In Malosma Laurina, Lauren Dam, Brinna Lee, Sarah Dahlberg, Stephen Davis
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The purpose of this study is to compare the stomatal conductance and xylem water potential between adults and resprouts of Malosma laurina growing at the Drescher Campus at Pepperdine University. Our data suggest that stomatal conductance and xylem water potential of adult and resprout M. laurina are not significantly different (p = 0.09312, p = 0.7064 respectively), implying that M. laurina at that study site has had sufficient time to recover from the drought due to the increased levels of rainfall.
Solar Tracking Fitness In Native Lupulinus Succulentus Vs. Non-Native Malva Sylvestris, Kathryn Maidlow, Logan Scott
Solar Tracking Fitness In Native Lupulinus Succulentus Vs. Non-Native Malva Sylvestris, Kathryn Maidlow, Logan Scott
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For this experiment, we hypothesized, that while both native and non-native species use solar tracking, the native species Lupulinus succulentus (bluebonnet) will solar track to increase light levels with low leaf temperatures; however, the non-native species Malva sylvestris (cheeseweed) will solar track to increase light levels with an elevated leaf temperature over the native species. Solar tracking was also hypothesized as a significant benefit to each plant species, thus we assumed that if a leaf was prevented from solar tracking that we would see a difference between the solar trackers and non-solar trackers of each species. We decided to use …
Reflectance, Transmittance, And Absorbance Values In Salvia Apiana Result In Better Performance Than Salvia Mellifera In Drought- Like Conditions, Haley Bekins, Caroline Boone, Kristen Hardin
Reflectance, Transmittance, And Absorbance Values In Salvia Apiana Result In Better Performance Than Salvia Mellifera In Drought- Like Conditions, Haley Bekins, Caroline Boone, Kristen Hardin
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Salvia apiana, due to the physically lighter color and thickness of the leaves, will have higher reflectance values, lower transmittance values, and lower absorbance values than Salvia mellifera. These measurements exemplify characteristics of a better adapted species for droughts, and then the absorption values can be used to calculate more information on the species like ERT. We measured transmittance and reflectance of six leaves from randomly selected plants of both species through the use of an integrating sphere. After obtaining the R and T value of each plant, we calculated the leaf absorbance,α. This was done by using the …
Dark-Adapted Fluorescence And Stomatal Conductance After Dcmu (3-(3,4-Dichlorophenyl)-1, 1-Dimethylurea)) Exposure On Malva Parviflora Plants, Piueti Maka, Mia Bryant, Isabelle Sarwono
Dark-Adapted Fluorescence And Stomatal Conductance After Dcmu (3-(3,4-Dichlorophenyl)-1, 1-Dimethylurea)) Exposure On Malva Parviflora Plants, Piueti Maka, Mia Bryant, Isabelle Sarwono
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The purpose of this experiment was to determine the disturbance effect of indirect exposure to DCMU (3-[3,4-dichlorophenyl]-1,1-dimethylurea), a popular herbicide, on dark adapted fluorescence and stomatal conductance in Malva parviflora plants. We utilized a test site exposed to sunlight and free from other external interference. Two main apparatuses were used to collect data; stomatal conductance was measured by a leaf porometer, and dark-adapted fluorescence (Fv/Fm) was measured using a Pulse Modulated Fluorometer. Our data yielded significant comparison results for dark-adapted fluorescence (P0.05). Additionally, observations six days after disturbance showed a drastic presence of hollyhock rust (Puccinia malvacearum) and …
A Comparison Of Photoprotection In C3 Plants Between A Native And An Invasive Species, T. Cao, M. Field, K. Godon
A Comparison Of Photoprotection In C3 Plants Between A Native And An Invasive Species, T. Cao, M. Field, K. Godon
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Now more so than ever with the increasing demands placed upon plant species as a direct result of climate change, competition between native and invasive species determines which species are able to survive and reproduce. Biologically the two species, native and invasive, carry out the same functions yet it is in how they carry out said functions that they differ. Prior to the commencement of the study the belief was held that the invasive species (here Avena) would contain increased photoprotection than the native species (here Elymus) for it to possess a competitive advantage. Testing of the stated hypothesis including …
Photoprotection Adaptiveness In Native (Lupinus Succulentus) And Invasive (Malva Parviflora) Heliotropic Plants, Joseph Davidson, Cameron Juarez, Collin Scott
Photoprotection Adaptiveness In Native (Lupinus Succulentus) And Invasive (Malva Parviflora) Heliotropic Plants, Joseph Davidson, Cameron Juarez, Collin Scott
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Addressed here is the question of whether invasive heliotropic plants can adapt better than native heliotropic plants, to conditions in which their solar tracking capabilities are hindered. In order to test this, a heliotropic species native to Southern California (Lupinus succulentus) was compared to a weedy heliotropic species invasive to Southern California (Malva parviflora). We hypothesized that the photoprotection mechanisms of M. parviflora would adapt better to being restrained as it is an invasive species and it was more abundant in the area. Values of Fv’/Fm’ and qN were measured in order to compare the efficacy …
Comparison Of Physiological Measurements And Water Potential Of Malosma Laurina During And After The Drought In Southern California, Nicolette Jessen, Kirstin Van Fleet, Rachel White
Comparison Of Physiological Measurements And Water Potential Of Malosma Laurina During And After The Drought In Southern California, Nicolette Jessen, Kirstin Van Fleet, Rachel White
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After 5 years of drought, southern California has recently experienced increases in precipitation. Malosma laurina is a chaparral shrub that displays vulnerability to fungal infection during severe drought conditions, particularly in its adult branches, resulting in severe dieback throughout the Santa Monica Mountains. M. laurina is known to produce resprout leaves during times of environmental stress that are less affected by the fungus based on its ability to maintain water status and thus are more capable of displaying resilience in more favorable environmental conditions. We hypothesize that the increase in rain will not be enough to alter the vitality of …