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Identification Of Downy Mildew Resistance In Wild Arugula And Evaluation Of Downy Mildew Causing Pathogens And Management Practices
Get PDFDowny mildew has been a potentially devastating constraint to crop production within the Brassicaceae family worldwide (CABI, 2022) and on the Central Coast of California (Smukler, et al, 2008; Koike, et al. 2007). Downy mildew is a foliar disease, caused by the pathogens in the Hyaloperonospora genus on plants within the Brassicaceae family (Goker, et al, 2009). Downy mildew is a disease that is common in region of the world with Coastal climates that provide humidity and moderate temperatures (Sarahan, et al, 2017). Crops within the Brassicaceae family maintain a predominant role in agricultural systems worldwide (Cartea, et al, 2011) and on the Central Coast of California, in Monterey, San Luis Obispo, Santa Cruz, San Benito, and Ventura Counties (Hidalgo, et al, 2022; Settevendemie, et al, 2022; Sanford, et al, 2022; Griffin, et al, 2022; Chang, et al, 2022; Williams, et al, 2022). The crop production within the Brassicaceae family includes broccoli, cabbage, and cauliflower, and the spring mix production of wild arugula, cultivated arugula, and baby kale. In the first study, an in-lab screening of wild arugula (Diplotaxis tenuifolia) for downy mildew resistance was conducted to identify accessions that contain potential resources of resistance to Hyaloperonospora diplotaxidis. The germplasm of 199 wild arugula accessions was grown out under greenhouse conditions and inoculated with a v single isolate of H. diplotaxidis. A subset of 40 accessions of wild arugula were further inoculated with an additional three isolates of H. diplotaxidis and the ten most resistant accessions were selected for further inoculations. The inoculations of the final subset of ten accessions with the same three isolates were replicated an additional two times. When a factorial ANOVA was conducted to test the interaction between the isolate and accession used, it was found that the impact of the accession on disease incidence was independent from the isolate (P=0.993). Three accessions, 185, 79, and 17 were identified as a potential source of resistance to the isolates utilized in this study, for maintaining a disease incidence below 1%. To compare the results found in the in-lab resistance screening, a field trial was conducted with a subset of wild arugula accessions with diverse reactions to downy mildew. When a regression was conducted comparing the disease incidence under field and lab conditions, the R2 value was found to be 0.37. A second study was conducted to characterize the genetic, morphological, and host range diversity of downy mildew causing pathogens in the Hyaloperonospora genus of hosts in the Brassicaceae family. An isolate collection of approximately 40 isolates of Hyaloperonospora spp. was established and the phylogenetic relationships of these isolates were analyzed by creating two phylogenetic trees using their cox2 mtDNA and ITS rDNA sequences. The H. brassicae and H. diplotaxidis isolates from this study formed separate monophyletic groups in both the cox2 mtDNA and ITS rDNA phylogenetic analyses. When the host range of H. brassicae and H. diplotaxidis were characterized by inoculating a genetically and morphologically diverse set of four host plant species, the H. brassicae and H. diplotaxidis were found to have distinct host ranges. The H. brassicae isolate was found to be parasitic of all B. oleracea morphotypes including broccoli, cabbage, kale, kohlrabi, and ornamental cabbage. The H. diplotaxidis isolate was found to only be parasitic on wild arugula, not cultivated arugula, wild mustard, or any of the B. oleracea morphotypes. The difference between sporangia of H. brassicae and H. diplotaxidis were found to be statistically significant, where the sporangia of H. brassicae were nearly circular and the sporangia of H. diplotaxidis were closer to an oval
Digital Audio Synthesizer
Get PDFWith more and more of the modern music production and live performance workflow becoming digitized synthesizers are the perfect middle ground between the traditional instrument layout and the progressive electronic sound. Despite the fact that synthesizers have made their place in the modern music pipeline they have one significant drawback. Synthesizers are expensive. Whether they are analog or digital, many of the synthesizers produced today are not affordable for the average musician or synth hobbyist. We will be designing a cost effective digital audio synthesizer that will still have enough versatility and a high enough quality to be useful in the music production process.
Many synthesizers, even digital ones, have been priced as luxury music making tools, with some systems having just a single oscillator costing upwards of $200. We have found that for many applications, synthesizers do not need to be this expensive and can usually be implemented using digital synthesis for a much cheaper price to performance ratio. By completing this project we have shown that it is possible to implement a quality synthesizer without making it excessively expensive. And while the current performance of our synthesizer meets our requirements, the feature-set is still limited. This prototype is meant to be a starting point or framework for future development. With further development and optimizations our synthesizer could compete with synthesizers that are currently on the market today. Although we do not anticipate that our project will have much effect on the overall synthesizer market, it may act as a motivating factor to help reduce the cost of commercial synthesizers and make synths more accessible overall
Building 21 Courtyard Barbecue Pit Demolition
Get PDFThis project intended to demonstrate the process of a full-scope demolition project at a manageable scale. Almost sixteen yards of concrete were to be demolished, including all reinforcing structures within the barbecue. The purpose of this project was to clear space for the impending renovation of Building 21’s courtyard and remove the unsafe barbecue from the busy pedestrian pathway. Sledgehammers were used in conjunction with electric jackhammers to perform the demolition. Rebar from demolition was separated from the concrete and recycled separately from any cementitious materials. Careful attention was given to protecting existing brick beneath the structure, the surrounding area, and any pedestrians that were in the vicinity. This project benefited the visual appeal of the courtyard, student and faculty safety, and cleared space for the architecture studio concurrently responsible for redesigning the courtyard. A demolition scope is the antithesis to most project-based senior projects and provided valuable insight on the trade, as well as unforeseen circumstances involved with removing old structures with little to no information available about them
Port Adapter for Unported Pressure Sensors
Get PDFBoundary layer research is an exciting and ever-changing field in fluid mechanics; thus, the need for high-quality empirical data is ever-growing in importance. Dr. Westphal, a professor at California Polytechnic State University, San Luis Obispo’s (Cal Poly) Mechanical Engineering Department in conjunction with Northrup Grumman is conducting just such research. Dr. Westphal has elected to make the change to pressure sensors that do not come with a built-in port to connect to pitot-static tubes. This necessitates a solution to adapt an unported pressure sensor to his testing apparatus which requires a tubed connection. This document outlines the Final Design Review (FDR) carried out by a team of mechanical engineering students attending Cal Poly. In this FDR, the team describes their design, its implantation, verification, and recommendations for the future. This includes how their design meets the engineering specifications the team set out to meet, the safety standards required for the design, and the manufacturing and assembly. This document will also describe the testing that the team conducted on their design. The engineering specifications have not changed since the Critical Design Review (CDR). The chosen design includes a Stereolithography (SLA) 3D printed body and lid that will form the complete enclosure and a stainless steel adapter that will connect to pitot tubes. The enclosure and connections will be sealed using various sealants. Testing results concluded the design met the design requirements of holding pressure at -40°C conditions; however, there remains room for improvement and future development
Supermileage Competition: Vehicle Chassis
Get PDFThe Supermileage Urban Concept Vehicle Chassis Project was proposed by the Cal Poly Supermileage club. The goal of this project is to deliver a fully assembled vehicle chassis by the end of the 2023-2024 school year to be used by the club in the 2025 Shell Eco-Marathon competition. The competition requires a four-wheeled vehicle to comply with various requirements outlined in the Shell Eco-Marathon rulebook, such as dimensions and some safety requirements. The team selected a backbone-style chassis as the design direction. This design consists of a main structural beam that supports all other chassis and vehicle components. This main beam will be a composite construction, while the remaining structural components will be steel weldments