Life Sciences Commons^™

Strawberry Powdery Mildew Caused By Podosphaera Aphanis: Fungicide Resistance And Host Plant Resistance, Michael G. Palmer

Master's Theses

Strawberry powdery mildew, caused by Podosphaera aphanis, affects leaves, fruit, and runners of strawberry plants. Infected leaves have reduced photosynthetic capability and infected fruit become unmarketable. Both of these factors translate to economic loss for the grower and therefore merit taking measures to control the disease. One objective of this study was to evaluate the resistance developed in populations of strawberry powdery mildew to chemical control measures. A fungicide assay was developed to evaluate the efficacy of six treatments (penthiopyrad, quinoxyfen, myclobutanil, trifloxystrobin, cyflufenamid, fluopyram + trifloxystrobin) for control of the disease. Nineteen isolates of strawberry powdery mildew were …

Eelgrass (Zostera Marina) Population Decline In Morro Bay, Ca: A Meta-Analysis Of Herbicide Application In San Luis Obispo County And Morro Bay Watershed, Tyler King Sinnott

Master's Theses

The endemic eelgrass (Zostera marina) community of Morro Bay Estuary, located on the central coast of California, has experienced an estimated decline of 95% in occupied area (reduction of 344 acres to 20 acres) from 2008 to 2017 for reasons that are not yet definitively clear. One possible driver of degradation that has yet to be investigated is the role of herbicides from agricultural fields in the watershed that feeds into the estuary. Thus, the primary research goal of this project was to better understand temporal and spatial trends of herbicide use within the context of San Luis …

Improving Sustainable Fertilizer Practices For Pomegranate By Leaf Nutrient Concentration Evaluation And Fertilizer Trials, Minh Le

Master's Theses

Fruit tree leaf nutrient concentrations are commonly used to determine fertilizer rates, but information is limited regarding nutrient requirements, seasonal N uptake and removal rates, and soil N dynamics for pomegranate. Relationships between fertilizer rates, leaf nutrient concentrations, fruit yield and quality were examined in five mature, commercial California ‘Wonderful’ pomegranate orchards. Site 1 was observed for two growing seasons (2018-2019) and sites 2-5 were observed for one season (2018 or 2019). In 2018, 150, 300, or 450 g N/tree was applied at sites 1-3 in a single application at early fruit development or in two equal applications at early …

Study Of Plants Used Against Infections By California Native American Tribes, Maria J. Rojas

Master's Theses

The objectives of this research were to evaluate the antibacterial activity and to determine the chemical composition of a list of medicinal plants used by Native Americans in California. Artemisia californica, Mimulus aurantiacus, Equisetum telmateia, Equisetum hyemale, and Marah fabacea were selected from a list of plants reported as having been used for ailments related to infections by tribes located in California. The extracts obtained through steam distillation from E. telmateia, E. hyemale and M. fabacea were assayed for in vitro antibacterial activity against 16 Gram-negative and 6 Gram-positive bacteria using disk diffusion assays and measuring the diameters of inhibition …

Sensory Stressors Impact Species Responses Across Local And Continental Scales, Ashley A. Wilson

Master's Theses

Pervasive growth in industrialization and advances in technology now exposes much of the world to anthropogenic night light and noise (ANLN), which pose a global environmental challenge in terrestrial environments. An estimated one-tenth of the planet’s land area experiences artificial light at night — and that rises to 23% if skyglow is included. Moreover, anthropogenic noise is associated with urban development and transportation networks, as the ecological impact of roads alone is estimated to affect one-fifth of the total land cover of the United States and is increasing in space and intensity. Existing research involving impacts of light or noise …

Pressure Driven Desalination Utilizing Nanomaterials, Fangyou Xie

Master's Theses

Nanomaterials such as graphene oxide and carbon nanotubes, have demonstrated excellent properties for membrane desalination, including decrease of maintenance, increase of flux rate, simple solution casting, and impressive chemical inertness. Here, two projects are studied to investigate nanocarbon based membrane desalination. The first project is to prepare hybrid membranes with amyloid fibrils intercalated with graphene oxide sheets. The addition of protein amyloid fibrils expands the interlayer spacing between graphene oxide nanosheets and introduces additional functional groups in the diffusion pathways, resulting in increase of flux rate and rejection rate for the organic dyes. Amyloid fibrils also provide structural assistance to …

Transgenerational Plasticity Causes Differences In Uv-Tolerance Of Intertidal And Subtidal Populations Of The Purple Sea Urchin, Strongylocentrotus Purpuratus, Yareli Alvarez, Nikki L. Adams

Master's Theses

Planktonic larvae of marine organisms are increasingly being exposed and required to respond to a changing physical environment. Adult sea urchins occupy both intertidal and subtidal waters and broadcast spawn gametes into the water column to contend with variable physical conditions. To answer how populations of invertebrates residing at different depths adequately prepare their offspring to cope with different levels of ultraviolet radiation (UVR), we collected adult purple sea urchins, Strongylocentrotus purpuratus, from four sites (two intertidal and two subtidal (~15 m deep)) on the central coast of CA to compare UV tolerance in offspring. Our measurements of UVA …

Maleic Anhydride Compatibilized Peach Waste As Filler In Polypropylene And High Density Polyethylene Biocomposites, Caralyn Wong, Stephanie Jung, Joongmin Shin, Ajay Kathuria

Master's Theses

It is estimated that roughly 103, 515 tons of peach waste is produced annually in the US. The majority of the waste is disposed of in landfills, which contributes to climate change as they release 93 million metric tons of CO₂ equivalent. Peach waste principally consists of remaining stone and seed after flesh removal. The agro-waste includes both cellulose and lignin, which can be utilized as a filler in plastic packaging to reduce carbon footprints and material cost. The objectives of this research are (1) to develop peach flour (PF)-filled biocomposites with a polyolefin matrix using maleic anhydride-g-high density …

Lipid Quantification And Cryopreservation Of In Vitro Produced Jersey Cattle Embryos, Katherine A. Rhodes-Long

Master's Theses

Cryopreservation of in vivo derived Jersey bovine embryos have resulted in a 10% lower pregnancy rate compared to other dairy breeds. Poor embryo survival after cryopreservation has been partially attributed to the high lipid content of Jersey embryos. In vitro-produced (IVP) bovine embryos have darker cytoplasm than their in vivo-derived counterparts because of higher lipid accumulation. High lipid accumulation is associated with impaired embryo quality. Forskolin is an adenylate cyclase activator that regulates cAMP levels in cells and has been shown to induce lipolysis in IVP embryos. L-carnitine is required for transport of fatty acids from the intermembrane space of …

Artificial Night Lighting And Anthropogenic Noise Alter Animal Activity, Body Condition, Species Richness, And Community Structure, Joshua Willems

Master's Theses

Sensory pollution from artificial night-lighting and anthropogenic noise have increased at a dramatic rate over the last several decades. Alterations to the sensory environment have been found to affect wildlife in a wide variety of ways including behavioral changes, physiological responses, changes in species interactions, and altered community structure. Increased levels of light and noise pollution can originate from many sources including roads, energy development and infrastructure, and urbanization. Even remote or protected areas are not immune to the effects of increased sensory disturbances with 63 percent of protected areas within the United States found to have been exposed to …

Quantifying The Ecological Drivers And Impacts Of Parrotfish Predation On Caribbean Corals Communities, Hannah Sima Rempel

Master's Theses

Parrotfishes (Scarinae) are dominant Caribbean herbivores that play an important role in reducing coral-algae competition by grazing algae; yet some species are also occasional coral predators (corallivores) and thereby can have direct negative impacts on coral growth and survivorship. There is concern that parrotfish corallivory may contribute to substantial long-term declines in targeted coral species, particularly in areas with a high biomass of parrotfishes and low cover of corals. However, the capacity of target coral species to heal from parrotfish predation and the ecological drivers of corallivory are poorly understood.

In Chapter 1, we examined the patterns of coral healing …

Feeling Out Your Food: A Histological Analysis Of The Whisker System In Seals, Cameron Cooper

Master's Theses

The vibrissal (whisker) system is present in nearly all mammals and is especially important in deep-diving mammals. Pinnipeds (seals, sea lions, and walruses) have highly sensitive whiskers that are used to follow hydrodynamic trails created by their swimming prey. Each pinniped vibrissa is surrounded by a tripartite blood sinus system composed of an upper cavernous sinus (UCS), a ring sinus (RS), and a lower cavernous sinus (LCS). The UCS has been hypothesized to play a thermoregulatory role, insulating temperature sensitive mechanoreceptors located within the vibrissal follicle. The aim of this study was to examine this hypothesis by measuring and comparing …

Maturation And Culture Media Effects On In Vitro Bovine Embryo Developmental Competence, Ciara M. Helland

Master's Theses

In vitro produced bovine embryos are critical to the cattle industry. However, these embryos have altered morphology, epigenetics, and metabolism when compared to their in vivo counterparts. The aim of this thesis was to alter maturation and culture media to improve the developmental competence of in vitro bovine embryos. This thesis is comprised of three experiments and one proof of concept study. Each experiment followed the same general layout: oocyte aspiration from Jersey or Holstein ovaries, oocyte maturation for 24 hours, fertilization with bull semen for 24 hours, then embryo culture for 7-8 days in 38.5 °C in 5% O …

The Influence Of The Sensory Environment On Avian Reproductive Success And Human Well-Being, Danielle Marie Ferraro

Master's Theses

Sensory pollutants such as anthropogenic noise and night lighting now expose much of the world to evolutionarily novel sound and night lighting conditions, which can have detrimental effects on humans and wildlife. In my first chapter, we exposed wild Western Bluebird (Sialia mexicana) nestlings to noise, light, and combination (i.e., noise and light) treatments. Nests exposed to noise and light together experienced less predation than control and light-exposed nests, and noise-exposed nests experienced less predation than control nests, yet overall nest success was only higher in noise-exposed nests compared to light-exposed nests. Although exposure to light decreased nestling body condition …

Attractiveness Of English Thyme (Thymus Vulgaris L.) To Arthropod Natural Enemies And Its Suitability As A Dual Use Resource, Kristina K. Van Wert

Master's Theses

Current agroecosystem management practices have a negative effect on natural enemies and their ability to control insect pests. Conservation biological control through the addition of flowering resources can manage food resources for natural enemies. These floral resources can also provide multiple ecosystem services. Study goals were to determine if perennial Thymus vulgaris L. was attractive to natural enemies and if so, could it be a dual use resource encouraging pest management and providing harvestable product. In 2018 plots in three locations were used to examine the effect of habitat throughout the growing season on the attractiveness of T. vulgaris. …

Analysis Of Biofilm Remediation Capacity For Octenyl Succinic Anhydride (Osa), A Bioactive Food Starch Modifier Compound, Matthew R. Borglin

Master's Theses

Matthew R. Borglin

This thesis demonstrates efficacy of Octenyl Succinic Anhydride (OSA), as a biofilm sanitizer. Biofilms allow bacteria to adhere to solid surfaces with the use of excreted polymeric compounds. For example, surfaces found in food production or processing facilities such as the interior of a raw milk holding tank, are some of the most susceptible to biofilm contamination. When present, biofilms can cause a variety of negative effects, which include; reduction of product shelf life, corrosion, and outbreaks of foodborne illnesses. The close association of biofilms with the majority of foodborne illness cases led the US Environmental Protection …

A Floristic Study Of The Cal Poly Swanton Pacific Ranch And A New Combination In Sanicula Crassicaulis (Apiaceae), Sanicula Crassicaulis Var. Nudicaulis, Reed J. Kenny

Master's Theses

Globally we are experiencing a biodiversity crisis and potentially a sixth mass extinction event. Plant specimens are one of the best, most concrete records of biodiversity that we can create. Despite this, the rate of plant collecting has declined steeply since World War II. Now more than ever, plant collections are vital, both for the purpose of quantifying the plant biodiversity in an area and for discovering previously unrecognized diversity.

In Chapter 1, we conducted a floristic survey of the Cal Poly Swanton Pacific Ranch. The Swanton Pacific Ranch (SPR) is located north of the small town of Davenport California, …

Cal Poly Pier Master Plan, Troy A. Lawson

Master's Theses

The Cal Poly Pier (Pier) Master/Facility Plan (FP) document provides the vision of the future for the Pier, a marine science research facility. The Plan facilitates project development and management of the Pier while meeting university and department research goals. Specifically, the FP document establishes goals and strategies to direct long-term development of the Pier, streamlines agency approval and permit requirements, provides context for pier management, and assists the permitting process for future development as it relates to regulatory permits and programmatic growth on the Cal Poly Pier to help meet goals of the Center for Coastal Marine Sciences (CCMS). …

Analysis And Optimization Of Colorimetric Nanosensors For Rapid Detection Of Microbes In Water, Ruby A. Lang

Master's Theses

Access to safe water is a basic human right recognized by the United Nations General Assembly in 2010 (WHO, 2020). However, a least 2.2 billion people globally still are without safely managed water services meaning they use a drinking water source that can be contaminated with faeces (WHO, 2020). With such a pressing global health issue, it is clear that improvement to water systems is important and required in the Agenda 2030 Sustainable Development Goals (SDGs). However, to improve water systems and prove they are safe water sources, water quality testing must occur. A solution to this issue is the …

Reduction Of Fat Content In Processed Meats Using Hot-Boning And Cold-Batter Mincing Technology, Morgan P. Wonderly

Master's Theses

Processed meats have received negative publicity due to high fat contents that have been linked to adverse effects on human health. Fat is an essential ingredient in many processed meat products, so reducing this all while maintaining the desired characteristics of the product is a challenge. The purpose of this study was to generate low-fat meat products using a combination of hot-boning/crust-freeze-air-chilling (HB-CFAC) and cold-batter mincing (CBM) technologies. Pork hams were subjected to HB-CFAC or chill-boning/crust-freeze-air-chilling (CB-CFAC) prior to 3 min pre-mincing and 6 min mincing for control gels with back-fat addition or low-fat gels with water addition instead of …

Pismo Clams (Tivela Stultorum) In Califorina: Population Status, Habitat Associations, Reproduction, And Growth, Alexandria R. Marquardt

Master's Theses

Marine shellfish play a vital role in intertidal ecosystems and coastal communities, but many of these fisheries are small-scale and lack the necessary monitoring to ensure long-term sustainability. Effective management often requires information on key demographic parameters, such as population status, reproduction and growth. Pismo clams (Tivela stultorum) are a culturally important and iconic species in California, which supported a thriving commercial and recreational fishery throughout much of the 1900’s. However, Pismo clam populations have declined statewide in recent decades and are attributed to human harvest and predation by California sea otters (Enhydra lutris); However, no …

Inactivation Of Foodborne Pathogens During Cider Fermentation, In A Cider Model System And Commerical Cider, Kathryn K. Yamada

Master's Theses

Hard cider is an alcoholic drink made from fermented crushed fruit, typically apples. The popularity of this fermented alcoholic beverage has been on the rise within the last decade. Historically, hard cider has been deemed safe due to the presence of ethanol and the low pH. Although there is lack of scientific evidence to prove that hard cider will and can be safe from foodborne pathogens. Escherichia coli O157:H7, Salmonella spp., and Listeria monocytogenes are three predominate foodborne bacterial pathogens of concern in the food and beverage industry. Escherichia coli O157:H7 in particular has been associated with fresh produce and …

Fruit, Flower, And Thorn: A Phenological Study Of 'Wonderful' Pomegranate, Kylie M. Mendonca

Master's Theses

‘Wonderful’ pomegranate flowering and fruiting habits are not well understood. Characterizing any relationship between flowering habit and fruit size and quality could lead to effective cultural practices for producing high-value fruit. Five mature ‘Wonderful’ pomegranate trees were monitored every 5-14 days throughout the 2015 growing season. Newly emerged flowers were tagged and characterized with respect to sex (determined by ovary shape and style length at anthesis), clustering habit, age of wood on which floral buds were borne, and direction of wood growth. More than 1,100 hermaphroditic flowers were identified and ovary/fruit diameter was recorded throughout the season. In addition to …

Valorization Of Carrot Processing Waste, Alexandra M. Duval

Master's Theses

Commercial carrot processors produce up to 175,000 tons of carrot waste annually. Carrot Mash (CM) is the term referring to the waste by-product of peeled baby carrot processing. Transportation of carrot processing waste is expensive due to its high- water content (approx. 83-95%). High in bioactive compounds (carotenoids) and dietary fibers, it is expected that its conversion into a value-added by-product is of interest to the carrot processing industry. Hemicellulose-rich plant materials have proven to be a source of oligosaccharides, which are known for their beneficial prebiotic activity. The objectives of this research were to: 1) determine the effect of …

Thermal Ecology Of The Federally Endangered Blunt-Nosed Leopard Lizard, Kathleen N. Ivey

Master's Theses

Recognizing how climate change will impact populations can aid in making decisions about approaches for conservation of endangered species. The Blunt-nosed Leopard Lizard (Gambelia sila) is a federally endangered species that, despite protection, remains in extremely arid, hot areas and may be at risk of extirpation due to climate change. We collected data on the field-active body temperatures, preferred body temperatures, and upper thermal tolerance of G. sila. We then described available thermal habitat using biophysical models, which allowed us to (1) describe patterns in lizard body temperatures, microhabitat temperatures, and lizard microhabitat use, (2) quantify the …

Patterns In Size Distribution And Catch Of Rockfish (Sebastes Spp.) In Fisheries-Independent And Fisheries- Dependent Hook-And-Line Surveys On The Central Coast Of California, Rose Elizabeth Dodgen

Master's Theses

Stock assessments are statistical models which characterize the state of a population of fish. Data for stock assessment models of West Coast nearshore groundfish come largely from fisheries-dependent sources. Incorporating fisheries-independent data would increase data availability. A potential source of fisheries-independent data which is comparable to existing fisheries-dependent data is the California Collaborative Fisheries Research Program (CCFRP), a Marine Protected Area (MPA) monitoring study. We are interested in understanding the context in which CCFRP could be implemented into assessments of nearshore groundfish, specifically rockfish. To investigate this, we used management-relevant metrics to examine three questions concerning the implementation of CCFRP …