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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
71

<b>Representation of whole-plant nutrient status with select individual leaves at multiple growth stages in maize</b><b> </b>

Brendan Jason Hanson (17112559) 10 December 2023 (has links)
<p dir="ltr">Routine testing of nutrient concentrations via plant tissue is an important component of in-season fertilizer management in maize (<i>Zea</i> <i>mays </i>L.) cropping systems. Accuracy of results are critical for nitrogen (N), phosphorous (P), potassium (K), and sulfur (S) management, yet there is little scientific guidance on which leaf to sample during mid- to late-vegetative growth stages. Additionally, the whole-plant status of each macro-nutrient may be best represented by a different leaf position due to mobility differences among nutrients. Mobility of each nutrient and allocation within the plant may also be influenced by environmental factors, management strategies, and genotype selection. Field experiments were conducted in West Lafayette and Windfall, Indiana in 2021 and 2022. The objectives were to (1) evaluate N, P, K, and S concentrations of specific leaf positions and whole plants in response to N fertilizer rate (NR), planting density (PD), and genotype (G) treatments at multiple growth stages, and (2) determine the ability of various leaf positions to predict whole-plant concentrations of N, P, K, and S across multiple NR, PD, and G environments. The West Lafayette study compared three NR treatments applied as urea-ammonium nitrate (UAN, 28-0-0) at the V5 growth stage and included (1) Control, no N applied, (2) 151 kg N ha<sup>-1</sup>, and (3) 241 kg N ha<sup>-1</sup>. The Windfall study compared two side-dress UAN rates of (1) Control, no N applied, and (2) 224 kg N ha<sup>-1</sup> at two planting densities (sub-plot) of 49,400 plants ha<sup>-1 </sup>and 89,000 plants ha<sup>-1</sup> with 4 Pioneer<sup>®</sup> genotypes (sub-sub-plot) including two historical double-cross hybrids and two modern single-crosses. Tissue sampling included the top-collared leaf and whole-plant at V8, the 8<sup>th</sup> leaf, top-collared leaf, and whole-plant at V12, and the 8<sup>th</sup> leaf, 12<sup>th</sup> leaf, ear-leaf, top-collared leaf and whole-plant at R1. Tissue N concentrations were consistently responsive to NR and PD treatments at all stages, but bottom leaves better reflected NR changes. As a mobile nutrient, N concentrations were highest in the uppermost leaf positions by R1 (ear-leaf and top-leaf), yet regressions between individual leaf and whole-plant N% were highest in the lower leaf positions (8<sup>th</sup> and 12<sup>th</sup> leaf positions). This suggested that the more likely a specific leaf was to exhibit nutrient deficiency symptoms, the better it would be at predicting whole-plant concentrations of that nutrient. Regressions between individual-leaf and whole-plant N% (modern genotypes only) increased from V8 to R1 and regressions were best with the 12<sup>th</sup> leaf position at both V12 and R1. Tissue S concentration responses to NR increased at later growth stages, and top-leaf S was a stronger reflection of whole-plant S than the 8<sup>th</sup> leaf. Despite S concentration differences among leaf positions at R1, the strength of regressions between each leaf position and whole-plant S were similar. There was no optimal leaf position to represent whole-plant S. While leaf N and S concentrations were above whole-plant concentrations, leaf P and K concentrations exhibited the opposite dynamic. There was little leaf P response to experimental treatment factors, and although regressions for leaf P versus whole-plant P concentrations were far weaker than for N, S or K, the 8<sup>th</sup> leaf position was preferred at V12 and R1 (R<sup>2</sup> of just 0.27 and 0.36, respectively). Potassium concentration response to NR was weak. However, leaf K% and whole-plant K% were highly related via regression, irrespective of NR, at all three stages. Prediction of whole-plant K was strongest with the 8<sup>th</sup> leaf at V12 and the 12<sup>th</sup> leaf at R1. In summary, optimum leaf sampling position was shown to vary with individual macronutrients and growth stages in maize. Although more research is essential, these preliminary results indicate that traditional sampling methods involving selection of the top fully-expanded leaf from V8 to silking, and the ear-leaf during post-silking stages, may not be the most reliable indicators of whole-plant nutrient status.</p>
72

Identifying Green Logistics Best Practice Leading to the Efficient Management of Resources and Waste in Thailand’s Public Hospitals

Bandoophanit, Thianthip January 2015 (has links)
The aim of this study is to identify green logistics (GL) best practice leading to the efficient management of resources and waste in Thai public hospitals. This work is influenced by and is aligned with the Thailand’s 2nd National Logistics and Supply Chain Research Strategies (2012-2016). The GL practices of six public hospitals were investigated, chosen to give coverage of the different types/sizes, locations and a range of environmental performance issues. Hospital visits were undertaken to collect data by interview, documentation and observation approaches. The GL best practices were principally identified by using developed indicators and a cross-case analysis method. The results of this study showed that resource and waste flows appeared very complicated within Thai hospitals. Thus, effectively introducing and managing GL within these settings requires the coordination of all staff (clinical and other), and the consideration of all environmental impacts from product purchasing through to waste disposal. Many beneficial practices for successfully reducing resource consumption and waste were identified. Key findings were that green initiatives need to be supported by: sufficient environmental education; two-way communication; effective evaluation and recording systems; and Director-level support. Importantly, GL adoption in the Thai context should be grounded in the Sufficiency Economy Philosophy concept (e.g. moderation, wisdom, and happiness), as well as contemporary hospital logistics theory and practice. Finally, it is recommended that the current Hospital Accreditation process is changed to integrate sustainable best practices, and that some pertinent government regulations and policies should be reviewed and changed as they were seen to be counterproductive and indeed in many cases it was proven that the enactment of the policies themselves actually increased waste. / Faculty of Management Sciences, Khon Kaen University.
73

Decentralizing electricity generation in Cuba : Implementation of a microgrid in the sugar mil lCarlos Baliño

Berber, Aylin, Eriksson, Cornelia January 2023 (has links)
Cuba has a long history of different dependencies and is a country facing many energy challenges, and therefore seeks to diversify its energy sources and reduce its reliance on fossil fuels. The purpose of this degree project is therefore to conceptualize a microgrid based on renewable energy sources for local energy sustainability at the lowest cost possible. For this purpose, the sugar mill Carlos Baliño and its surrounding community, in Villa Clara, Cuba is used for a case study. The currently existing electricity generation at Carlos Baliño is tied to the steam needed to run the sugar production process, which is generated with a back-pressure steam engine. This thesis evaluates the possibility to extend the system including a condensing extraction steam turbine connected to a new generator, solar PV, and wind power by developing and comparing three scenarios for the future. The BASE scenario is the business as-usual case including no changes, the PLAN scenario is based on the plans of installing a 1 MW solar PV power plants, and the APT scenario includes all possible technologies to be part of the system. For all scenarios, the different microgrid configuration were evaluated based on the following key performance indicators; CAPEX, NPV, IRR and DPP of the microgrid, share of electricity supplied from the grid and lastly the emission reduction rate compared to the current system in Carlos Baliño. In addition to the technical, economic, and social perspective, the results are evaluated in relation to the national context and goals. Evolution of microgrids is significant to develop more sustainable power systems. The key advantages of this microgrid solution include reduced greenhouse gas emissions, increased energy independence, and improved resilience in the electricity supply. By utilizing bagasse and renewable energy sources like solar PV and wind, Cuba can reduce its dependence on imported fossil fuels, leading to lower carbon emissions and contributing to global climate change mitigation efforts. Moreover, the integration of bagasse-based cogeneration plants enhances the country's energy resilience by diversifying the energy mix and reducing vulnerability to external energy shocks. The distributed nature of microgrids enables local communities to generate their own clean energy, fostering self-sufficiency and socioeconomic empowerment. The results show negative NPV for the BASE and PLAN scenarios. When including a Condensing Extraction Steam Turbine generator, the electricity supplied from the grid decreases from 30 to 11% for the BASE scenario and even more for the PLAN. Additionally, for the PLAN scenario, the 1 MW solar PV investment in isolation generates a positive NPV of 2.67 million USD indicating a good investment even though the whole system shows infeasibility and should increase the solar PV installation size to become profitable. Lastly, for the APT scenario, the NPV is 59.8 million USD, with an IRR of 11% and payback time of 7 years showing a good investment. However, with a high CAPEX of 41.3 million USD. The emission reduction rate is as high as 92%. Furthermore, a sensitivity analysis is performed to address the uncertainty in different cost parameters affecting the results of the study. And the result shows that the system NPV is most sensitive to the change in cost in bagasse fuel price. In conclusion, the integrated microgrid solution with solar PV and bagasse represents a sustainable and resilient energy option for Carlos Baliño and Cuba in general. By capitalizing on its solar potential and utilizing bagasse as a local biomass resource, Cuba can achieve a greener and more reliable energy system while promoting rural development and reducing carbon footprint. This solution can serve as a blueprint for other regions in Cuba and the Caribbean with similar energy challenges seeking to transition to renewable energy and achieve energy security. / Kuba har en lång historia av olika beroenden och är ett land som står inför många energiutmaningar, och försöker därför diversifiera sina energikällor och minska sitt beroende av fossila bränslen. Syftet med detta examensarbete är därför att konceptualisera ett mikronät baserat på förnybara energikällor för lokal energihållbarhet till längsta möjliga kostnad. För detta ändamål genomförs en fallstudie av sockerfabriken Carlos Baliño och dess närliggande samhälle, i Villa Clara, Kuba. Den nuvarande elproduktionen vid Carlos Baliño är kopplad till den ånga som behövs för att driva sockerproduktionsprocessen, som genereras med en back-pressure turbin. Vårt mål är att utvärdera möjligheten att utöka systemet och inkludera en CEST-generator, solcellsenergi och vindkraft. Dem olika konfigurationerna på mikronätet utvärderas utifrån följande nyckeltal; CAPEX, NPV, IRR och DPP för mikronätet, andel el som levereras från nätet och slutligen utsläppsminskningstakten jämfört med det nuvarande systemet i Carlos Baliño. Utöver det tekniska, ekonomiska och sociala lokala perspektivet utvärderas resultaten i relation till nationella sammanhang och mål. Utvecklingen av mikronätet är viktig för att utveckla mer hållbara kraftsystem. De viktigaste fördelarna med denna mikronätslösning inkluderar minskade växthusgasutsläpp, ökat energioberoende och förbättrad motståndskraft i elförsörjningen. Genom att använda bagass och förnybara energikällor som solenergi och vindkraft kan Kuba minska sitt beroende av importerade fossila bränslen, vilket leder till lägre koldioxidutsläpp och bidrar till globala klimatförändringar. Dessutom förbättrar integrationen av bagass-baserade kraftvärmeverk landets energitålighet genom att diversifiera energimixen och minska sårbarheten för externa energichocker. Mikronätets möjlighet till distribuerad energiproduktion gör det möjligt för lokalsamhällen att generera sin egen rena energi, vilket främjar självförsörjning och socioekonomisk egenmakt.  Resultaten visar en negativ NPV för BASE och PLAN scenarierna. När en Condensing Extraction Steam Turbine generator inkluderas minskar eltillförseln från nätet från 30 till 11% i BASE scenariot och ännu mer för PLAN. Dessutom, för PLAN scenariot, ger 1 MW solcellsinvesteringen en positiv NPV på 2,67 miljoner USD när den beräknas för sig själv, vilket indikerar en bra investering. Däremot är hela systemet inte ekonomiskt möjlig, och bör öka solcellsanläggningens storlek för att bli lönsam. Slutligen, för APT scenariot, är NPV 59,8 miljoner USD, med en IRR på 11% och en återbetalningstid på 7 år, vilket visar på en bra investering. Dessutom med en utsläppsminskningsgraden är så hög som 92%. Dock med en hög CAPEX på 41,3 miljoner USD. Vidare görs en känslighetsanalys för att ta itu med osäkerheten i olika kostnadsparametrar som påverkar studiens resultat. Och resultatet visar att systemets NPV är mest känsligt för förändringen i priset på bagassbränslet. Sammanfattningsvis representerar den integrerade mikronätlösningen med solceller och bagass ett hållbart och motståndskraftigt energialternativ för Carlos Baliño och Kuba i allmänhet. Genom att utnyttja sin solpotential och använda bagass som en lokal biomassaresurs kan Kuba uppnå ett grönare och mer tillförlitligt energisystem samtidigt som det främjar landsbygdsutveckling och minskar koldioxidavtrycket. Denna lösning kan fungera som en plan för andra regioner på Kuba och Karibien med liknande energiutmaningar som försöker gå över till förnybar energi och uppnå energisäkerhet.
74

From Protected to Productive

Takkar, Sonal January 2020 (has links)
The Stockholm Archipelago has a unique natural landscape - rugged nature that blends with wooded islands, rocky cliffs and sandy beaches enriched by cultural and ecological values. The islands, dating back to the Viking Age are faced with a progressively uneven growth compared to the city developing an inevitable socio-economic dependency on the city core through infrastructural connections. Emigration from already diffusely scattered settlements made life unaffordable on the islands for both permanent residents and municipalities. According to official surveys and analyses, the islands claimed to lack a live-work-play balance and social potential that could be developed better for the residents. This struggle is loaded with the seasonal influx of tourists who exploit the landscape, leaving the responsibility for care onto those who live there. This situation added to climate change, strains energy and (water) resources causing summer droughts. All these struggles raise a question for the future - “How can urban planning and design help re-imagine the potential of existing systems to adapt to a more sustainable Archipelago?” The project envisions to transform the fragmented, protected landscape of the Stockholm Archipelago into a continuous productive landscape, bringing meaning to the scattered and dynamic context. With an approach that closely integrates fields of planning, landscape and design, the goal is realised through a three-layered strategy - (1) continuous blue-green systems of resource capture and nutrient circulation, (2) building local economy through collective production and diversification through exchange, and (3) community exchange through robust networking and production as a way of life. For design possibilities on the local scale, the island of Runmaro is explored with the aim of building synergies with the existing context of landscape, mobility networks, food production, resident villages, local businesses and popular landmarks. The idea is to strengthen existing socio-economic nodes while developing new ones through programs offering shared production and exchange, a year-round activation and continuous accessibility (circulation and systemic) that bring continuity to the overall experience.
75

A Comparison among Three Bridge Performance Measures for Allocating Funds

Zhang, Chi 12 December 2018 (has links)
No description available.
76

Lika barn lajkar bäst - Miljönyheter på Facebook

Al-Qassam, Ahmed, Pettersson, Anton January 2016 (has links)
Studien tittar på miljönyhetssidorna Supermiljöbloggen och Aktuell Hållbarhet, samt den slutna gruppen Omställning Sverige, på Facebook. Vi har utfört en innehållsanalys på de 40 mest gillade inläggen under tidsperioden 1 april 2015 – 31 mars 2016 på respektive sida. Vi valde att kategorisera inläggen utifrån vilken aktör som ansvarar för lösningen/problemet. Är det staten, vetenskapen, individen eller marknaden? Vi har även placerat inläggen och sidorna i ett spektrum mellan följande idéströmmningar; ekologisk modernisering och sufficiency. Vi har funnit att de inlägg som lockar till sig flest gilla-markeringar, i både Supermiljöbloggen och Aktuell Hållbarhet, överensstämmer med en svagare ekologisk modernisering. Detta korrelerar även med att de dominerande aktörerna på dessa sidor är Staten och Marknaden. Omställning Sverige- gruppens inlägg uppvisar mestadels en diskurs som följer mikro-sufficency vilket också korrelerar med Individen som största aktör. Att ekologisk modernisering lockar till många gilla- markeringar tror vi beror på ett mer slagkraftigt språkbruk än sufficiency. / Social media is today established as a natural part of peoples information-gathering. Different framings of the environment in media triggers actors to act in different ways. We studied therefore the newspages Supermiljöbloggen and Aktuell Hållbarhet on Facebook. We also included the closed group Omställning Sverige in the study. We conducted a content analysis of the 40 most liked post from each page or group, during the time span 1 April 2015 - 31 March 2016. The posts were categorised from which actor that was responsible for the solution/problem. Is it the State, the Scientific sector, the Individual or the Market? We have also placed the posts and the pages/group in the spectra of the though paradigms: Ecological Modernisation and Sufficiency. We have found that the posts that attracts the most likes in both Supermiljöbloggen and Aktuell Hållbarhet, is in accordance to the weaker ecological modernisation. This also correlates with the dominating actors on these pages, which are the State and the Market. The posts in the group Omställning Sverige proves to have a discourse that is according to mikro-sufficiency which correlates with the Individual as the greatest actor. The reason why ecological modernisation attracts alot of likes is, according to us, partly because of the hard-hitting use of language compared to Sufficiency.
77

Off-Grid Tiny Housing : An Investigation of Local Sustainable Heat and Power Generation for an Artificial Island in Stockholm

Björnberg, Inez, Tarus, Anita January 2021 (has links)
A growing world population has resulted in an increasing number of people being homeless or living in inadequate housing. In addition, the threatening climate crisis and the world’s limited resources calls for a more sustainable way of living. The organization Stockholm Tiny House Expo aims to contribute a solution to these issues: an artificial island with several tiny houses, able to adapt to rising sea levels, having net-zero-waste and completely self-sufficient regarding energy. This island will symbolize the sustainable development goals and will be an attraction for tourists, as well as create several job opportunities. In order to realize this vision, research needs to be conducted to find solutions to make this island become reality. Therefore, the aim of this project is to evaluate the economic and environmental feasibility of a high degree of self-sufficiency regarding energy, by locally producing heat and power, on an artificial island in Stockholm. Firstly, a literature review is conducted to find suitable technologies to supply the island with heat and power. Subsequently, the software tools IDA ICE and HOMER Pro are used to simulate the energy demand and supply of the island. Eight different scenarios, with different types of supply and demand, are created to investigate different possibilities of the island. The scenarios are evaluated using technical-, economic- and environmental key performance indicators. A scenario where the demand is reduced and heat and power are supplied only by resources on the island, is deemed most relevant based on Stockholm Tiny House Expo’s vision. A sensitivity analysis is therefore performed on this scenario. The results indicate technical and environmental feasibility; however, the economic evaluation showed that this scenario will be non-profitable. Although the scenario is non-profitable, if further measures are taken to create a pricing model to customers, it could be possible. In conclusion, the results of this research indicate that it is possible for Stockholm Tiny House Expo to be self-sufficient regarding heat and power solely utilizing renewable energy. The evaluation of the results, however, showed that it is not economically feasible. In addition, the national grid did not contribute to an impact on the surrounding environment, nor to a considerable amount of greenhouse gas emissions. Hence, grid connection is recommended for Stockholm Tiny House Expo. / En växande världspopulation har resulterat i att ett ökande antal människor är hemlösa eller bor i bristfälliga bostäder. Den hotande klimatkrisen och jordens begränsade tillgångar kräver dessutom en hållbarare livsstil. Organisationen Stockholm Tiny House Expo vill bidra med en lösning till dessa problem: en artificiell ö med flera småhus, som kan anpassa sig till stigande havsnivåer, har noll nettoavfall och är helt självförsörjande gällande energi. Denna ö kommer symbolisera FN:s hållbarhetsmål och vara en turistattraktion så väl som skapa ett flertal arbetsmöjligheter. För att förverkliga denna vision krävs forskning för att hitta lösningar och göra denna ö till verklighet. Därmed är syftet med detta projekt att undersöka den ekonomiska och miljömässiga genomförbarheten av en hög grad av självförsörjning av energi, genom att lokalt producera kraft och värme, på en artificiell ö i Stockholm. Först utförs en litteraturstudie för att hitta lämpliga teknologier för att försörja ön med kraft och värme. Därefter används programvarorna IDA ICE och HOMER Pro för att simulera energibehovet och energiförsörjningen för ön. Åtta olika scenarier, med olika typer av försörjning och behov, konstrueras för att undersöka olika möjligheter för ön. Scenarierna utvärderas med hjälp av tekniska-, ekonomiska- och miljömässiga nyckeltal (key performance indicators). Ett scenario där behovet är reducerat samt att kraft och värme endast försörjs av resurser på ön, bedöms vara mest relevant baserat på Stockholm Tiny House Expos vision. En känslighetsanalys utförs därför på detta scenario. Resultaten tyder på att scenariot är tekniskt och miljömässigt genomförbart; dock visade den ekonomiska utvärderingen att det inte är lönsamt. Trots detta så skulle det kunna vara möjligt om vidare åtgärder tas för att skapa en prissättningsmodell mot kunderna. Sammanfattningsvis så tyder resultaten på att det är möjligt för Stockholm Tiny House Expo att vara självförsörjande gällande kraft och värme som endast utnyttjar förnybar energi. Utvärderingen av resultatet visade dock att det inte är ekonomiskt genomförbart. Det nationella kraftnätet bidrog dessutom inte till påverkan på den omgivande miljön och inte heller någon betydande mängd växthusgasutsläpp. Följaktligen rekommenderas nätanslutning för Stockholm Tiny House Expo.
78

Identifying green logistics best practices: a case study of Thailand's public hospitals

Bandoophanit, T., Breen, Liz, Barber, Kevin D. 09 1900 (has links)
Yes / Purpose Previous research (Bandoophanit et al, 2017) has shown that pharmaceuticals are a key input into effective healthcare operations but other equally important inputs are medical supplies, food, utilities, equipment and linen. As stated by the Twelfth National Economic and Social Development Plan (2017-2021) of Thailand, to attempt to deliver national Sustainable Development Goals (SDGs) organisations should preserve resources and minimize waste-generation in all aspects. The principal aim of this research project was to identify green practices and develop a model which supported and promoted healthcare efficiencies. Research Approach This was a mixed methods multi-site study using both qualitative and quantitative data collection and analysis methods. Six public hospitals were selected as case organizations, covering different types/sizes, locations, and environmental performance expertise. The data collection methods included interviews, documentation reviews and in situ observations. Respondents’ selection was purposive and a bespoke form of content analysis was used for the data review before further cross-case analysis, resulting in the identification of best practices using key indicators. Findings and Originality In spite of facing financial crisis, by reviewing key logistical processes and lifecycle, the overuse of healthcare resources and the poor management of waste, were clearly identified within in this study. This had a negative effect on personnel and patient hygiene. The result of identifying effective GL practices were reported as: (i) promoting the usage of multiple-use medical devices that can minimize inputs, waste, and cost, and (ii) producing/selecting organic food materials and fruits and reusing these waste byproducts to create secondary products e.g. fertilizer, biogas and electricity and cleaning/sterilizing liquid. The results also indicated that there was a drive from leaders to introduce green and efficient systems to improve staff personnel awareness and engagement in this area. The output of this study presents a model for GL implementation guidance, grounded in Thailand’s Sufficiency Economy Philosophy (SEP) concept. Research Impacts Currently, healthcare green logistics has received limited attention in developing nations and this study contributes to the reduction of these gaps. The SEP concept promotes sustainable health standards and underpins the focus and the originality/impact of this study. Practical Impacts This study recommends that staff in Thai hospitals focus on effective resource and waste management to contribute to sustainable sufficiency. This allows Thailand to offer an effective healthcare service to its patients. The study presents guidance and support to do this.
79

Weathering the Storm: Hurricane Resiliency in the Florida Keys

Begley, David Douglas 23 July 2018 (has links)
How can architects let their buildings interact with the water while protecting occupants from the potential danger? The two intents are very different and often compete with one, either protection or recreation, as the primary program in one project. Water draws people, everyone likes being near water. People visit waterfalls and the beach just to experience moving water, they go boating and kayaking just to be on the water. Water views and access are considered an amenity that drive up prices in buildings. Whenever possible architects should strive to connect their architecture and water and to let occupants interact with the water. However, water can be dangerous too. Overfull rivers wash away roads and cars. Floods inundate entire cities, and hurricanes devastate huge islands. In addition to catastrophic damage sea levels are rising around the world causing damage and rendering low lying land uninhabitable. Architects must protect against these dangers. If designed correctly buildings can offer shelter from storms and resist rising water of all kinds. For my thesis I decided to study how to reconcile these two conflicting approaches to water. / Master of Architecture
80

Hops Production in Virginia: Nutrition, Fungal Pathogens, and Cultivar Trials

Judd, Barslund Duane 29 November 2018 (has links)
In the United States, hops (Humulus lupulus L.) are grown mainly in the Pacific Northwest (PNW). For this reason, most cultural information is based on the growing conditions of the PNW. Growing conditions in Virginia differ drastically and present unique disease and production challenges. Three studies were conducted with the intent of increasing hop cultivation knowledge for Virginia growers. For the first study, 13 cultivars of hops grown at the Virginia Tech hop yard were compared for growth, yield, and quality. Mean cone fresh weight per plant ranged from 12.00 g for Mt. Hood to 1002.87 g for Crystal in 2016 and from 97.98 g for Mt. Hood to 900.33 g for Cascade in 2017. In 2016, only Alpharoma, Cascade, Mt. Rainier, and Southern Cross had alpha acid levels, an indicator of cone quality, within the accepted range. In 2017, Alpharoma, Centennial, Mt. Rainier, and Nugget had alpha acid levels within the expected range. Three cultivars (Cascade, Crystal, and Ultra) were above the expected alpha acid range, which indicates more bittering potential for beer brewers. In a nutrient deficiency study, hop plants were grown in hydroponic solutions, and deficiencies were induced for nitrogen (N), phosphorus (P), and potassium (K). After visual deficiency symptoms had been induced, leaf tissue samples were taken and analyzed for nutrient content. Images were taken at each deficiency stage. For N, incipient deficiency symptoms were observed at a mean of 3.18% dry weight in leaf tissue samples. Visual symptoms included a chlorotic appearance, undersized leaves, and red petioles. Incipient symptoms for P were observed at a mean of 0.307% dry weight in leaf tissue samples. Necrotic spots, leaf cupping, and undersized leaves were apparent with this deficiency. Incipient symptoms for K were observed at a mean of 1.21% dry weight in leaf tissue samples. Symptoms included rounded leaf tips, blue veins, and marginal scorch. In the third study, a whole leaf powdery mildew (Podosphaera macularis) assay was developed and tested using five hop cultivars, Alpharoma, Cascade, Comet, Sorachi Ace, and Tahoma. Leaves were inoculated with powdery mildew (PM) using a settling tower. This method was used to rapidly assess the resistance of cultivars. Leaves were successfully inoculated and PM colonies were allowed to grow for two weeks. Images of the PM colony development on inoculated leaves were compared using ImageJ to determine percentage of coverage. Tahoma was the only cultivar found to produce a significantly different mean percent coverage (19.5%) compared with the resistant cultivars Cascade and Comet (<1%). / Master of Science in Life Sciences / Hops (Humulus lupulus) were first grown in the United States in Massachusetts in the early 1600s. Production of this crop eventually spread throughout the Northeastern US. By the mid-1800s, commercial production spread to southern states such as Virginia. Infestation of pests, e.g., hop aphid and diseases such as downy mildew in eastern states, and prohibition on the production of alcohol caused a significant shift in hop production, which favored the Pacific Northwest (PNW). As a result, in Virginia specific knowledge of hop cultivation is now lacking. Three studies were conducted to increase our knowledge of hop cultivation for the region. For the first study, 13 cultivars grown at the Virginia Tech hop yard were compared for growth, yield, and quality. The cultivars Cascade and Alpharoma had alpha acid levels equal to or higher than expected for the 2016 and 2017 seasons. The alpha acid levels are an indicator of the hop quality from the Cascade and Alpharoma cultivars. Cascade was also a top producer of hop cones with a mean fresh weight of 989.67 g and 900.33 g in 2016 and 2017, respectively. In a nutrient deficiency study, plants were grown in Hoagland hydroponic solutions, which contain all essential nutrients needed for plant growth. This was done to provide photographic documentation to assist local growers with deficiency identification. Deficiencies were induced for nitrogen (N), phosphorus (P), and potassium (K) by removing each of the specific nutrient of interest from each treatment solution. After deficiency symptoms were induced, leaf tissue samples were taken and analyzed for nutrient content. Nutrient deficiencies were documented using photographs. For N, visual symptoms included a chlorotic appearance, undersized leaves, and red petioles. Incipient symptoms for P included necrotic spots, leaf cupping, and undersized leaves. For K, leaf cupping, blue green veins, marginal scorch, and rounded leaf tips. Disease resistance of cultivars is important information for growers and can heavily influence hop yard planning. As such, in another study, an assay for powdery mildew (Podosphaera macularis) was developed that allows for rapid low cost testing of hop cultivars. The assay was tested on the following cultivars: Alpharoma, Cascade, Comet, Sorachi Ace, and Tahoma. Leaves were inoculated with powdery mildew (PM) using a settling tower. Powdery mildew colonies were allowed to grow for two weeks and were then analyzed using ImageJ software to determine percent coverage. At the end of the experiment, Tahoma had significantly greater PM coverage compared to the other cultivars, indicating that Tahoma is less resistant to the specific PM strain. / Hops (Humulus lupulus) were first grown in the United States in Massachusetts in the early 1600s. Production of this crop eventually spread throughout the Northeastern US. By the mid-1800s, commercial production spread to southern states such as Virginia. Infestation of pests, e.g., hop aphid and diseases such as downy mildew in eastern states, and prohibition on the production of alcohol caused a significant shift in hop production, which favored the Pacific Northwest (PNW). As a result, in Virginia specific knowledge of hop cultivation is now lacking. Three studies were conducted to increase our knowledge of hop cultivation for the region. For the first study, 13 cultivars grown at the Virginia Tech hop yard were compared for growth, yield, and quality. The cultivars Cascade and Alpharoma had alpha acid levels equal to or higher than expected for the 2016 and 2017 seasons. The alpha acid levels are an indicator of the hop quality from the Cascade and Alpharoma cultivars. Cascade was also a top producer of hop cones with a mean fresh weight of 989.67 g and 900.33 g in 2016 and 2017, respectively. In a nutrient deficiency study, plants were grown in Hoagland hydroponic solutions, which contain all essential nutrients needed for plant growth. This was done to provide photographic documentation to assist local growers with deficiency identification. Deficiencies were induced for nitrogen (N), phosphorus (P), and potassium (K) by removing each of the specific nutrient of interest from each treatment solution. After deficiency symptoms were induced, leaf tissue samples were taken and analyzed for nutrient content. Nutrient deficiencies were documented using photographs. For N, visual symptoms included a chlorotic appearance, undersized leaves, and red petioles. Incipient symptoms for P included necrotic spots, leaf cupping, and undersized leaves. For K, leaf cupping, blue green veins, marginal scorch, and rounded leaf tips. Disease resistance of cultivars is important information for growers and can heavily influence hop yard planning. As such, in another study, an assay for powdery mildew (Podosphaera macularis) was developed that allows for rapid low cost testing of hop cultivars. The assay was tested on the following cultivars: Alpharoma, Cascade, Comet, Sorachi Ace, and Tahoma. Leaves were inoculated with powdery mildew (PM) using a settling tower. Powdery mildew colonies were allowed to grow for two weeks and were then analyzed using ImageJ software to determine percent coverage. At the end of the experiment, Tahoma had significantly greater PM coverage compared to the other cultivars, indicating that Tahoma is less resistant to the specific PM strain.

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