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Mokrushina, Ksenia. "Sustainability transformations in Olympic host cities." Thesis, Massachusetts Institute of Technology, 2012. http://hdl.handle.net/1721.1/73706.
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Thesis (M.C.P.)--Massachusetts Institute of Technology, Dept. of Urban Studies and Planning, 2012.This electronic version was submitted by the student author. The certified thesis is available in the Institute Archives and Special Collections.
Cataloged from student submitted PDF version of thesis. Page 101 blank.
Includes bibliographical references (p. 95-100).
The Olympic Games represent an unparalleled fast-track urban development opportunity for Olympic host cities. Taking the premise that the transformational effect of the Olympics has a potential to drive long-term urban sustainability, this thesis examines how Olympic host cities can use the Olympic planning process to transition to a more sustainable model of urban development. Presenting the case of the Vancouver 2010 Olympics, this thesis draws planning lessons for Sochi 2014 and other future Olympic host cities and discusses policy implications for the International Olympic Committee. The City of Vancouver's systematic efforts to integrate sustainability principles in Olympic planning created sustainability co-benefits exceeding the initial sustainability commitments of the bid book. The development of the Olympic Village generated a massive amount of urban sustainability learning by the City planning staff, thus majorly accelerating sustainability policies in the areas of energy efficiency, green building, district energy, urban design and agriculture. Taking advantage of an unprecedented opportunity to experiment with the "urban laboratory" of the Olympics, the City fostered improved citizens' perception of public space and transit, which gave rise to a sustained increase in transit ridership, walking and biking after the Games. The City was able to achieve these outcomes through integrating the Games into its long-term urban development strategy, strategic sustainability thinking and visioning, principled approach to planning, building partnerships with key stakeholders and leveraging resources from senior levels of government, ensuring that the interests of the organizing committee and city entrepreneurs do not dominate the planning process, engaging and consulting with community groups and educating the citizens. Lasting sustainability legacies of the Vancouver Olympics arose from a highly collaborative, inclusive and coordinated process involving all levels of government, multiple City agencies, private sector, VANOC, community groups and citizens. The applicability of the policy lessons learned from Vancouver's case is questionable in developing countries, authoritarian regimes and cities with little to no previous experience in urban sustainability. The IOC should play a more active role in preventing sustainability debacles in these policy contexts.
by Ksenia Mokrushina.
M.C.P.
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Hutton, Anne K. "The Olympic Games, lessons for future host cities." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 2001. http://www.collectionscanada.ca/obj/s4/f2/dsk3/ftp05/MQ63528.pdf.
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Oshanski, Kari Ann. "The Impact of Olympics on Public Open Space in Host Cities." The Ohio State University, 2013. http://rave.ohiolink.edu/etdc/view?acc_num=osu1366293753.
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Erten, Sertac. "Spatial Analysis Of Mega-event Hosting: Olympic Host And Olympic Bid Cities." Phd thesis, METU, 2008. http://etd.lib.metu.edu.tr/upload/12609390/index.pdf.
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The aim of this dissertation is to provide a new perspective to the analysis of megaevent / host city relationship. The significance of the research subject depends on the
interest in hosting mega-events such as the Olympic Games and the World Fairs, which generate a competition among cities. Turkish cities are recently being involved in this competition. In addition to that, mega-events have large-scale and long-term impacts on the built environment, which has not been thoroughly discussed in urban studies. The methodology which is based on a qualitative analysis comprises three steps: a historical analysis made on the Olympic host cities, and two case studies. The first case is Athens as the 2004 Olympic city, the second case is Istanbul as an Olympic bid city since 1990. This study recognizes but qualifies the concept of megaevent hosting. It is shown that mega-event hosting is a capacity-building process, whilst it has a potential to generate overdose investments problem in the built environment. The most significant conclusion of the study is that the ability of coping with this problem is correlated with the ability of absorbing the investments made.
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Hobbs, Nicholas. "A Review of Olympic Host Cities: Analyzing the Exclusion of South American and African States." Scholarship @ Claremont, 2014. http://scholarship.claremont.edu/cmc_theses/1721.
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The Olympic Games are a global phenomenon that focus a spotlight onto the hosting city once every two years. While the athletes are judged on their physical abilities, the host city is judged on its architecture, organization and capabilities. It is a chance to showcase your city and country to the world. But while athletes from all over the world are welcome to compete in the games, becoming a host city has only been granted to a few countries, not reaching all seven continents. One must look into what it takes to host the Olympic Games and what factors are creating an exclusionary trend.
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Königshofer, Franz. "Die österreichischen host cities der UEFA EURO 2008 Städte zwischen Festivalisierung, Inszenierung und nachhaltiger Entwicklung im Zuge des Events unter spezieller Berücksichtigung von Wien." Saarbrücken VDM Verlag Dr. Müller, 2007. http://d-nb.info/986581941/04.
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Muthuthantri, Weerawickramage Sakuntala Nayanatara. "Citrus host utilisation by the Queensland fruit fly, Bactrocera tryoni (Frogatt) (Diptera:Tephritidae) : from individuals to populations." Thesis, Queensland University of Technology, 2013. https://eprints.qut.edu.au/62855/2/Weerawickramage_Muthuthantri_Thesis.pdf.
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Fruit flies are the insects which cause maggots in your backyard fruit and vegetables. They are not just a nuisance to gardeners, but the single greatest insect threat to commercial and subsistence fruit growers throughout Asia, Australia and the Pacific. Queensland fruit fly, the focus of this PhD, costs Australia an estimated $100million per year. I focused specifically on how Queensland fruit fly uses different commercial citrus varieties. I identified specific plant related mechanisms which increase a fruit’s resistance to fruit fly attack. This information can be used by plant breeders to make fruit less prone to fruit fly damage.
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Almeida, Dulce Moreno Marques de. "Pedestrian streets for sustainable cities : highlight on design strategies to control hot summer conditions outdoors." Thesis, Open University, 2006. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.489039.
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Zhang, Kai. "Hong Kong citizens' attitude toward hot spot policing." Thesis, University of Macau, 2011. http://umaclib3.umac.mo/record=b2456345.
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Vantini, Juliana da Silva [UNESP]. "Ativação das vias relacionadas a resistência de Citrus sinensis em resposta a interação com a bactéria Xanthomonas axonopodis." Universidade Estadual Paulista (UNESP), 2007. http://hdl.handle.net/11449/92699.
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Made available in DSpace on 2014-06-11T19:26:09Z (GMT). No. of bitstreams: 0
Previous issue date: 2007-01-30Bitstream added on 2014-06-13T18:54:10Z : No. of bitstreams: 1
vantini_js_me_jabo_prot.pdf: 1997059 bytes, checksum: d7a4eb83f1290513e650d32a88072bd9 (MD5)Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)
Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)
A citricultura vem sendo constantemente ameaçada pela bactéria gram negativa Xanthomonas axonopodis pv. Gitri (Xac-A) , causadora do cancro cítrico. Esta bactéria, quando em contato com uma planta hospedeira, lesiona folhas, frutos e ramos. Por outro lado, quando este patógeno infecta uma planta não-hospedeira provoca uma reação necrótica no sítio de infecção (reação de hipersensibilidade). Os diversos mecanismos de defesa da planta ao ataque do patógeno, incluem aqueles mediados por genes codificadores da produção de ácido salicílico, ácido jasmônico, fitoalexinas, proteínas PR, dentre outros. Neste trabalho investigou-se a expressão dos genes codificadores de Fenilalanina amônia liase (FAL), Aleno oxido sintase (AOS), Chalcona sintase (CHS) e J3-1,3-glucanase (PR-2) na interação Xanthomonas axonopodis pv. aurantifolii C (Xaa-C)
The production of citrus fruits has being constantly threatened by the gram negative bacterium Xanthomonas axonopodis pv. citri (Xac-A) , the citrus canker disease agent. This bacterium, when in contact with host plants, induce canker lesions on leaves, fruits and branches. On the other hand, when this pathogen infects a non-host plant a necrotic reaction is induced at the infection site as a hypersensitive-like reaction. Plant defense mechanisms to pathogen attack include induction of genes coding to salicylic acid, jasmonic acid, phytoalexines and PR proteins. The expression of resistance related genes phenylalanine ammonia Iyase (PAL), aliene oxide syntase (AOS), chalcone syntase (CHS) and 13-1,3-glucanase (PR-2) were investigated on the Xanthomonas axonopodis pv. aurantifolii C (Xaa-C)
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Grace, Pamela Lynne Lewiston. "Cathouses on a hot tin roof? legal prostitution and urban growth in Washoe and Storey counties /." abstract and full text PDF (free order & download UNR users only), 2008. http://0-gateway.proquest.com.innopac.library.unr.edu/openurl?url_ver=Z39.88-2004&rft_val_fmt=info:ofi/fmt:kev:mtx:dissertation&res_dat=xri:pqdiss&rft_dat=xri:pqdiss:1453587.
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Kerns, David L., and Tony Tellez. "Evaluation of Insecticide Applications for Citrus Thrips Control Under Hot Conditions." College of Agriculture, University of Arizona (Tucson, AZ), 2002. http://hdl.handle.net/10150/226071.
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A small plot efficacy trial was conducted evaluating citrus thrips control under hot conditions. Average daily maximum temperatures ranged from the mid-90’s to low 100°F’s. Success and Carzol were the most efficacious products evaluated, followed by Lorsban and Dimethoate. Both Lorsban and Dimethoate provided good initial thrips control but were short lived. Lorsban appeared to have a slightly longer residual than Dimethoate. Both of the pyrethroids, Baythroid and Danitol, performed poorly. Neither provided good thrips knockdown or residual control. Pyrethroids should be avoided for thrips control when temperatures equal or exceed 95°F. We were not able to demonstrate any adverse effect on efficacy towards thrips by acidifying Success. However, Success is not prone to hydrolysis at high pHs, and acidification is not necessary or advised.
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Matheron, M., and J. Matejka. "Evaluating the Potential Threat to Citrus Plantings from Phytophthora Parasitica Originating from Noncitrus Hosts." College of Agriculture, University of Arizona (Tucson, AZ), 1991. http://hdl.handle.net/10150/215727.
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The relative virulence of Phytophthora parasitica recovered from citrus and other plants to rough lemon was investigated Isolates of Phytophthora parasitica from citrus were highly virulent to rough lemon seedlings, causing crown rot and significant reduction of root weight. Isolates of the pathogen from noncitrus hosts caused slight damage to rough lemon, with no crown rot and only minor reduction of root weight. Evidently, isolates of P. parasitica from several noncitrus hosts do not pose a serious threat to citrus groves.
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Doggett, Jeffrey. "The Citizen Institution| The Role of Two Small, Nonurban Colleges as Anchors in Their Host Communities." Thesis, University of Pennsylvania, 2018. http://pqdtopen.proquest.com/#viewpdf?dispub=10828999.
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Anchor institutions are colleges and universities that, in recognition of the interdependence they share with their host community, collaboratively engage in effort to better their locale. Anchors strategically approach community partnerships and the contribution of institutional assets they provide towards selected efforts that are beneficial to both the community and the institution. The study of these types of citizen institutions are of value because they serve as models of democracy that stand in contrast to the atrophied civic life our country currently suffers. Despite the benefits communities, students, and institutions themselves derive from colleges and universities engaging in an anchor mission, there is currently a lack of recognizable or relatable illustrations of anchor engagement by which to be inspired and after which to emulate. Overcoming this barrier is achieved by offering illustrations of a more representative group of anchor institutions to inspire all types of institutions to adopt an anchor mindset and help build the types of communities that foster a more positive civic life.
Toward that end, the community mission and engagement of Bates College in Lewiston, Maine, and Central College, in Pella, Iowa were explored through case study methodology to develop a robust understanding of how each institution implements its civic mission and engages in its host community as an anchor institution. With a focus on each institution’s thematic approach to their (a) civic responsibility, (b) democratic engagement, and (c) anchor contributions, a set of key components emerged that serve as foundational underpinnings of the efforts of these two colleges. Specifically, the existence of community values such as trust, networks and assets, dictate how each college and their community partners engage in common purpose actions that seek to address societal issues. That partnership engagement is advanced by Bates and Central through their democratic engagement approach of listening, learning and delivering which weaves through each of the identified themes.
With the identification of these two small, nonurban anchor institutions, the definition of anchor institution is broadened, and more relevant examples of anchor engagement are provided, to inspire replication by more similarly sized and located institutions.
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Soriano, Leonardo. "Organogênese in vitro e transformação genética de variedades de tangerina (Citrus reticulata Blanco e Citrus clementina hort. ex Tan.)." Universidade de São Paulo, 2015. http://www.teses.usp.br/teses/disponiveis/64/64133/tde-19052015-142119/.
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Atualmente, o Huanglongbing (HLB), doença associada à bactéria Candidatus Liberibacter spp., é a principal ameaça dos Citrus, não tendo sido encontrado ainda espécies resistentes e tolerantes. O melhoramento genético tradicional apresenta limitações para a obtenção de novas variedades porta-enxerto e copa de citros em decorrência a fatores ligados à biologia do gênero. Na tentativa de sobrepor essas dificuldades, a transformação genética destaca-se por permitir a introdução de genes exógenos, os quais, além de reduzir o período de obtenção de material melhorado geneticamente, poderão conferir resistência a doenças em variedades de interesse agronômico. Desse modo, o objetivo desta pesquisa consistiu no estudo da organogênese in vitro, e na obtenção de plantas transgênicas via Agrobacterium tumefaciens das tangerinas \'Fremont\', \'Thomas\' e \'Nules\', com o gene que codifica o peptídeo antibacteriano atacina A (attA), controlado pelos promotores AtSUC2 e AtPP2, visando a expressão gênica preferencial nos vasos do floema. Adicionalmente, foi avaliada a transformação genética via A. tumefaciens de suspensões celulares de tangerina \'W-Murcott\', de laranja doce \'Hamlin\' e de tangelo \'Page\', e a transformação genética direta via PEG de protoplastos da tangerina \'W-Murcott\', com os fatores de transcrição VvmybA1 e Ruby, dirigidos pelos promotores com expressão preferencial nos tecidos embrionários 6105 e DC3. A eficiência da organogênese in vitro foi influenciada pelo tipo de explante e concentração de BAP. Após os experimentos de transformação genética de segmentos de epicótilo e internodal das tangerinas \'Fremont\', \'Thomas\' e \'Nules\', as plantas regeneradas foram analisadas por PCR, Southern blot e RT-qPCR e confirmadas como transgênicas pela presença e transcrição do gene attA no tecido vascular. A transformação genética de suspensões celulares mostrou-se eficiente com alta produção de antocianina nos embriões somáticos regenerados de tangerina \'W-Murcott\', de laranja doce \'Hamlin\' e de tangelo \'Page\'. A transformação genética direta de protoplastos de tangerina \'W-Murcott\' mostrou-se viável e também foi possível a obtenção de embriões somáticos transgênicos. Os fatores de transcrição VvmybA1 e Ruby se mostraram úteis para detecção visual do material transgênicoCurrently, Huanglongbing (HLB), associated to Candidatus Liberibacter spp., is the main threat to the citrus culture. The conventional plant breeding shows limitations to the obtain new varieties of rootstock and scion, due to factors related to the biology of the genus. In attempt to overcome these barriers, genetic engineering is notable for allowing the introduction of foreign genes, which, besides reducing the time to obtain genetically improved material may confer disease resistance in varieties of agronomic interest. Thus, the objective of the research was the study of in vitro organogenesis, and obtain transgenic plants of \'Fremont\', \'Thomas\' and \'Nules\' mandarins via Agrobacterium tumefaciens with the gene encoding the antibacterial peptide attacin A (attA), controlled by the promoters AtSUC2 and AtPP2, aiming to preferential gene expression in phloem. In addition, the genetic transformation of cell suspensions, via A. tumefaciens, of \'W-Murcott\' mandarin, \'Hamlin\' sweet orange and \'Page\' tangelo and the direct genetic transformation, via PEG, of \'W-Murcott\' mandarin protoplasts were evaluated with VvmybA1 and Ruby transcription factors driven by 6105 and DC3 promoters, with preferential expression in embryonic tissues. The in vitro organogenesis of the varieties studied was influenced by the type of explant and BAP concentration. After genetic transformation experiments of epicotyl and internodal segments of \'Fremont\', \'Thomas\' and \'Nules mandarins, regenerated plants were analyzed by PCR, Southern blot and RT-qPCR and confirmed as transgenic by presence and transcription of attA gene. The genetic transformation of cell suspensions was efficient with high anthocyanin production in the somatic embryos regenerated of \'W-Murcott\' mandarin, \'Hamlin\' sweet orange and \'Page\' tangelo. The direct genetic transformation of \'W-Murcott\' mandarin protoplasts revealed to be viable and it was also possible to obtain transgenic somatic embryos. The VvmybA1 and Ruby transcription factors were useful tools for visual detection of transgenic material
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Alves, Gustavo Rodrigues. "Efeitos de variedades citricas sobre o vetor das bactérias associadas ao Huanglongbing (HLB) Diaphorina citri Kuwayama, 1908 (Hemiptera: Liviidae)." Universidade de São Paulo, 2017. http://www.teses.usp.br/teses/disponiveis/11/11146/tde-03082017-092226/.
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O Huanglongbing (HLB) ou \"greening\" é considerada, atualmente, a mais séria doença da citricultura no mundo, cujos sintomas estão associados às bactérias \"Candidatus Liberibacter spp.\". Uma vez que não há medidas curativas para a doença, o manejo baseia-se em medidas curativas como o controle de Diaphorina citri, vetor do patógeno. Esse inseto apresenta uma gama de hospedeiros de mais de 50 espécies da família Rutaceae, incluído as espécies e variedades do gênero Citrus, porém, nem todos os hospedeiros permitem o completo desenvolvimento do inseto. Dessa forma, objetivou-se com este trabalho verificar a existência de características de variedades cítricas de copa e porta-enxerto, mais utilizadas na citricultura, que afetam os aspectos bioecológicos de D. citri, bem como caracterizá-las, de modo que possam servir de base para desenvolvimento de estratégias de manejo do inseto vetor. Para isso, foram estudados: 1) comportamento de escolha hospedeira de D. citri em diferentes combinações de variedades de copa e porta-enxerto e a identificação dos voláteis envolvidos; 2) os efeitos das combinações copa e porta-enxerto na biologia de D. citri e 3) estudos sobre o comportamento alimentar de D. citi por meio da técnica de Electrical Penetration Graph em diferentes variedades de copa de citros. Verificou-se comportamento de escolha diferenciado entre fêmeas e machos de D. citri em função do hospedeiro. O porta-enxerto não influenciou o comportamento de escolha de D. citri. Foram observadas diferenças significativas na qualidade e quantidade nos perfis de voláteis liberados pelos diferentes hospedeiros, com a predominância de terpenoides. As variáveis biológicas de D. citri foram afetadas pelos hospedeiros. A variedade \'Hamlin\' foi classificada como a menos adequada ao psilídeo independentemente do porta-enxerto utilizado. Houve influencia da variedade de copa de citros no consumo alimentar de D. citri. Utilizando-se a técnica de EPG não é possível observar diferenças no comportamento alimentar de D. citri entre os hospedeiros testados.Huanglongbing (HLB) or \"greening\" is currently considered the most serious citrus disease worldwide, whose symptoms are associated with the bacteria \"Candidatus Liberibacter spp.\". Since there are no curative measures for the disease, management is based on curative measures like control of the pathogen vetor, Diaphorina citri. This insect has a range host of more than 50 species of the family Rutaceae, including species and varieties of the genus Citrus, but not all hosts allow the complete development of the insect. Thus, the objective of this study was to verify the existence of characteristics of citrus scion and rootstock varieties, more used in the citriculture, that affect the bioecological aspects of D. citri, as well as characterize them, serving as basis for development of management strategies for this insect vector. For this, were studied: 1) host choice behavior of D. citri in different combinations of scion and rootstock varieties and the identification of the volatiles involved; 2) the effects of scion and rootstock combinations on the biology of D. citri and 3) studies on the feeding behavior of D. citi using the Electrical Penetration Graph technique in different varieties of citrus scion. There was a differentiated choice behavior between males and females of D. citri depending on the host. The rootstock did not influence the choice behavior of D. citri. Significant differences were observed in the quality and quantity of the volatiles released by the different hosts, with the predominance of terpenoids. The biological variables of D. citri were affected by the hosts. The \'Hamlin\' variety was classified as less suitable to the psyllid independently of the rootstock used. There was influence of the citrus scion variety on the food intake of D. citri. Through EPG technique it is not possible to observe differences in the feeding behavior of D. citri among the hosts tested.
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Esteves, Mariana Bossi. "Seleção de plantas hospedeiras experimentais para ensaios de transmissão da estirpe de citros de Xylella fastidiosa." Universidade de São Paulo, 2015. http://www.teses.usp.br/teses/disponiveis/11/11146/tde-12032015-171921/.
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A clorose variegada dos citros (CVC) é uma das principais doenças que afeta a citricultura brasileira, causada pela bactéria Xylella fastidiosa (Wells), que coloniza o xilema de culturas de interesse econômico, além de plantas ornamentais e daninhas, sendo transmitida por cigarrinhas (Hemiptera: Cicadellidae: Cicadellinae). A compreensão do patossistema CVC é fundamental para planejar táticas eficazes de controle da doença. Entretanto, as pesquisas sobre interações patógeno-planta-vetores são escassas, devido à falta de plantas hospedeiras adequadas para ensaios de transmissão da bactéria, visto que citros não é um bom hospedeiro experimental. Assim, nesta pesquisa objetivou-se identificar espécies herbáceas que permitam a colonização sistêmica da estirpe de X. fastidiosa de citros, e avaliar seu uso como plantas-fonte e plantas-teste (indicadoras) em testes de transmissão por Bucephalogonia xanthophis (Berg). Para tal foram escolhidas as plantas Bidens pilosa L., Catharanthus roseus L., Citrus sinensis (L.) Osbeck, Medicago sativa L., Nicotiana tabacum L., Ocimum basilicum L., Parthenium hysterophorus L., Phaseolus vulgaris L., Sida rhombifolia L. e Solanum americanum Mill, que foram inoculadas mecanicamente com isolados de X. fastidiosa de citros e posteriormente avaliadas quanto à infecção por isolamento primário e reação de cadeia da polimerase (PCR). As espécies que permitiram colonização bacteriana foram posteriormente avaliadas em experimentos de transmissão por B. xanthophis, sendo divididos em duas etapas. Na primeira delas, variaram-se as espécies de plantas-fonte para aquisição da bactéria e fixou-se C. roseus como planta-teste para inoculação. Na segunda etapa, fixou-se C. roseus como planta-fonte e variaram-se as espécies de planta-teste. Durante os experimentos de transmissão, foram avaliados dois parâmetros biológicos de B. xanthophis: mortalidade (%) e volume de honeydew excretado (medida indireta de ingestão). Entre 30 a 90 dias após a inoculação, as plantas-testes foram analisadas quanto à infecção bacteriana por meio de PCR e isolamento. As inoculações mecânicas mostraram colonização sistêmica e multiplicação de X. fastidiosa em sete espécies vegetais (B. pilosa, C. roseus, C. sinensis, M. sativa, N. tabacum, O. basilicum e S. americanum), com maiores taxas de infecção e populações bacterianas em C. roseus e N. tabacum. As espécies C. roseus, M. sativa e O. basilicum, quando usadas como plantas-fonte de X. fastidiosa, propiciaram maiores volumes de excreção e menores taxas de mortalidade (15, 20 e 20%) da cigarrinha após 48 h de acesso à aquisição da bactéria. No experimento de transmissão com variação de espécies de plantas-teste, detectou-se a inoculação pelo vetor em C. roseus, M. sativa, O. basilicum e S. americanum, com maior proporção de plantas positivas (cerca de 20%) para as duas primeiras. Dentre essas espécies, C. roseus e M. sativa são as indicadoras mais adequadas para ensaios de transmissão de X. fastidiosa por B. xanthophis, sendo a primeira também adequada como planta-fonte.Citrus variegated chlorosis (CVC) is a major disease that affects the Brazilian citrus industry, caused by the xylem-limited bacterium Xylella fastidiosa (Wells), which colonizes several crop plants, ornamentals and weeds, and is transmitted by sharpshooter leafhoppers (Hemiptera: Cicadellidae: Cicadellinae). A better understanding of the CVC pathossystem is critical for developing effective tactics to control the disease. However, research on the relationships among pathogen strains, host plants and insect vectors associated with CVC is scarce, partly because of the lack of adequate host plants for transmission assays, since citrus is not a suitable experimental host for this purpose. Thus, the present study aimed to identify herbaceous plants that allow systemic colonization of citrus strains of X. fastidiosa, and evaluate them as source and test (indicator) plants in transmission assays by the sharpshooter Bucephalogonia xanthophis (Berg). Ten plant species, Bidens pilosa L., Catharanthus roseus L., Citrus sinensis (L.) Osbeck, Medicago sativa L., Nicotiana tabacum L., Ocimum basilicum L., Parthenium hysterophorus L., Phaseolus vulgaris L., Sida rhombifolia L. and Solanum americanum Mill were mechanically inoculated with citrus isolates of X. fastidiosa and then evaluated for bacterial infection by primary isolation in culture medium and polymerase chain reaction (PCR). Those plant species that allowed bacterial colonization were later evaluated in two transmission experiments by B. xanthophis, In the first experiment, different plant species were tested as source plants for bacterial acquisition and transmission to C. roseus (test plant). In the second one, C. roseus was used as a source plant and different plant species were evaluated as test (indicator) plants for bacterial inoculation. During the transmission experiments, two biological parameters of B. xanthophis were evaluated: mortality rate (%) and honeydew excretion (as an indirect measure of ingestion). Between 30 and 90 days after inoculation, the test plants were analyzed for X. fastidiosa infection by PCR and culturing. The mechanical inoculation experiments showed systemic colonization and multiplication of X. fastidiosa in seven plant species (B. pilosa, C. roseus, C. sinensis, M. sativa, N. tabacum, O. basilicum and S. americanum), with higher rates of infection and bacterial populations of C. roseus and N. tabacum. The species C. roseus, M. sativa and O. basilicum, when used as source plants of X. fastidiosa, allowed higher ingestion (honeydew excretion) rates and lower mortality (15, 20 and 20%) of B. xanthophis during the 48-h acquisition access period. In the transmission experiment with different species of test plants, X. fastidiosa inoculation by the vector was detected in C. roseus, M. sativa, O. basilicum and S. americanum, with a higher rate of infected plants (about 20%) in the former two species. Among the herbaceous plant species evaluated in this research, C. roseus and M. sativa are the most appropriate indicator hosts of X. fastidiosa infection for transmission assays by B. xanthophis, whereas the former species is also suitable as a source plant.
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Vantini, Juliana da Silva. "Ativação das vias relacionadas a resistência de Citrus sinensis em resposta a interação com a bactéria Xanthomonas axonopodis /." Jaboticabal : [s.n.], 2007. http://hdl.handle.net/11449/92699.
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Resumo: A citricultura vem sendo constantemente ameaçada pela bactéria gram negativa Xanthomonas axonopodis pv. Gitri (Xac-A) , causadora do cancro cítrico. Esta bactéria, quando em contato com uma planta hospedeira, lesiona folhas, frutos e ramos. Por outro lado, quando este patógeno infecta uma planta não-hospedeira provoca uma reação necrótica no sítio de infecção (reação de hipersensibilidade). Os diversos mecanismos de defesa da planta ao ataque do patógeno, incluem aqueles mediados por genes codificadores da produção de ácido salicílico, ácido jasmônico, fitoalexinas, proteínas PR, dentre outros. Neste trabalho investigou-se a expressão dos genes codificadores de Fenilalanina amônia liase (FAL), Aleno oxido sintase (AOS), Chalcona sintase (CHS) e J3-1,3-glucanase (PR-2) na interação Xanthomonas axonopodis pv. aurantifolii C (Xaa-C)::Citrus (resposta de resistência) e o comportamento dos mesmos na interação Xac-A::Citrus (cancro cítrico). Folhas de laranjeira (Citrus sinensis) inoculadas com suspensões bacterianas (Xac-A ou Xaa-C) foram coletadas em diferentes tempos de infecção. A expressão dos genes foi analisada por Northern blot com a ajuda de sondas específicas de C. sinensis obtidas via amplificação por PCR, com a utilização de oligonucleotídeos específicos dos genes em questão e DNA genômico de folhas de laranjeira. Os genes fal, aos, chs e pr-2 foram expressos mais intensamente na interação Xaa-C:Citrus onde uma reação de resistência não-hospedeira é capaz de evitar o desenvolvimento de sintomas de cancro, quando comparados com a interação Xac-A:Citrus que leva ao cancro cítrico.Abstract: The production of citrus fruits has being constantly threatened by the gram negative bacterium Xanthomonas axonopodis pv. citri (Xac-A) , the citrus canker disease agent. This bacterium, when in contact with host plants, induce canker lesions on leaves, fruits and branches. On the other hand, when this pathogen infects a non-host plant a necrotic reaction is induced at the infection site as a hypersensitive-like reaction. Plant defense mechanisms to pathogen attack include induction of genes coding to salicylic acid, jasmonic acid, phytoalexines and PR proteins. The expression of resistance related genes phenylalanine ammonia Iyase (PAL), aliene oxide syntase (AOS), chalcone syntase (CHS) and 13-1,3-glucanase (PR-2) were investigated on the Xanthomonas axonopodis pv. aurantifolii C (Xaa-C)::Citrus sinensis interaction (resistance response) or on Xanthomonas axonopodis pv. citri estirpe A (Xac-A)::Citrus sinensis (citric canker) interaction. Orange leaves inoculated with bacterial suspensions (Xac-A or Xaa-C) were collected at different moments during infection. Resistance related gene expression was analyzed by Northern blot with the aid of citrus probes obtained by PCR amplification using specific oligonucleotides and orange leaves genomic DNA. The resistance related genes paI, aos, chs and pr-2 have shown a more intense expression on the (Xaa-C)::Citrus interaction which induce non-host resistance response, when compared to the citrus canker Xac-A::Citrus inducing interaction.
Orientador: Julio Cezar Franco de Oliveira
Coorientador: Maria Inês Tiraboschi Ferro
Banca: Manoel Victor Franco Lemos
Banca: Poliana Fernanda Giachetto
Mestre
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Cifuentes, Arenas Juan Camilo [UNESP]. "Huanglongbing e Diaphorina citri: estudos das relações patógeno-vetor-hospedeiro." Universidade Estadual Paulista (UNESP), 2017. http://hdl.handle.net/11449/151391.
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Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)
O huanglongbing (HLB), associada a bactérias de floema (Candidatus Liberibacter spp) transmitidas por insetos (Diaphorina citri), é a doença mais destrutiva dos citros e muitos têm sido os esforços visando reduzir sua disseminação nos pomares, porém, nem sempre bem-sucedidos. Somente no cinturão citrícola paulista mais de 45 milhões de plantas já foram erradicadas por causa do HLB. O objetivo deste trabalho foi investigar diferentes aspectos associados ao patossistema HLB, visando trazer informações que ajudem na contenção da doença. Foram estudados: 1) hospedeiros alternativos do inseto vetor e do patógeno; 2) ontogenia do broto vegetativo de citros e seu potencial em multiplicar D. citri; 3) requerimentos térmicos para o desenvolvimento do broto; e 4) influência do porta-enxerto na biologia de D. citri. No primeiro capítulo é apresentada revisão de literatura sobre os aspectos mais relevantes da citricultura e do patossistema em estudo e, nos demais, os resultados das pesquisas. No segundo é apresentada a importância Swinglea glutinosa (rutácea muito comum em certas regiões citrícolas) como fonte de Ca. Liberibacter asiaticus e criadouro de D. citri. A bactéria do HLB multiplicou na planta, porém atingiu populações consideravelmente menores do que em laranjeira ‘Valência’. Apresenta, portanto, baixo potencial como fonte de inóculo para os citros. Por outro lado, D. citri reproduziu abundantemente em S. glutinosa, tanto quanto nas principais variedades de laranjeiras doces e limoeiros do grupo ‘Siciliano’ cultivados no Brasil. No terceiro capítulo são apresentados detalhes do desenvolvimento do broto em laranjeira ‘Valência’ e como os diferentes estádios influenciam o potencial biótico de D. citri. O inseto completou seu ciclo de vida em todos os estádios, mas em diferentes intensidades, sendo maiores nos estádios iniciais. Com os dados criou-se um índice de favorabilidade à reprodução do inseto, que leva em consideração o peso relativo de cada estádio do broto na biologia do inseto. No quarto capítulo é apresentado o impacto da temperatura do ar sobre o broto, o que permitiu determinar os graus-dia necessários ao seu desenvolvimento (GDD) e, com base no GDD, estabelecer um modelo geral inovador de previsão de pulverizações. No quinto capítulo é demonstrado que o porta-enxerto (limoeiro Cravo, tangerineira Sunki e citrumeleiro Swingle), por mecanismos de antibiose e/ou antixenose, afetam D. citri. Mas esses fenômenos ocorrem somente na fase de seedlings, e nas copas neles enxertadas somente enquanto a planta é jovem (muda). Em plantas adultas, de maior porte, tais fenômenos não foram detectados. Podem ter sido mascarados por influência da variedade copa (laranjeira).
Huanglongbing (HLB), associated with insect-borne phloem bacteria (Candidatus Liberibacter spp), is the most destructive disease of citrus and many efforts have been made to reduce its spread in orchards, but not always well-succeeded. Only in the citrus belt of São Paulo state (Brazil), more than 45 million plants have already been eradicated because of HLB. The objective of this work was to investigate different aspects associated to the HLB pathosystem, aiming to bring information that helps in the management of the disease. We studied: 1) alternative vector insect and pathogen hosts; 2) ontogeny of the citrus vegetative shoot and its potential to multiply D. citri; 3) thermal requirements for shoot development; and 4) influence of the rootstock on the biology of D. citri. In the first chapter, a literature review on the most relevant aspects of citriculture and pathosystem in study is presented and, in the others, the results of the experiments. In the second one the importance of Swinglea glutinosa (a Rutaceae very common in certain citrus regions) as a source of Ca. Liberibacter asiaticus and host for D. citri is presented. The HLB bacteria multiplied in the plant, but reached populations considerably smaller than in 'Valencia' sweet orange. Therefore, it presents low potential as a source of inoculum for citrus. On the other hand, D. citri reproduced abundantly in S. glutinosa, as well as in the main sweet orange and lemon varieties of the 'Sicilian' group cultivated in Brazil. In the third chapter, it is presented details of the development of the 'Valencia' orange new shoot and how the different stages influence the biotic potential of D. citri. The insect completed its life cycle at all stages of new shoots, but at different intensities, being larger in the early stages. With the data, an insect reproduction index was created, which takes into account the relative weight of each shoot stage in the insect biology. In the fourth chapter, it is presented the impact of the air temperature on the shoot, which allowed to determine the degree-days required for its development (GDD) and, based on the GDD, to establish an innovative general model of spray forecasting. In the fifth chapter it is demonstrated that the rootstock (‘Rangpur’ lime, ‘Sunki’ mandarin and ‘Swingle’ citrumelo), by mechanisms of antibiosis and / or antixenosis, affect D. citri. But these phenomena occur only in the stage of seedlings, and in the scions grafted on them only while the plant is young (nursery tree). In larger adult plants, such phenomena were not detected. They may have been masked by the influence of the scion (orange) variety.
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Maia, Ozana Maria de Andrade [UNESP]. "Transmissibilidade da leprose das cercas-vivas, quebra-ventos e plantas daninhas para citros através de Brevipalpus phoenicis (Geijskes, 1939) (Acari: Tenuipalpidae)." Universidade Estadual Paulista (UNESP), 2002. http://hdl.handle.net/11449/91304.
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maia_oma_me_jabo.pdf: 901159 bytes, checksum: e78a92958b754c82d637ebb566194d6e (MD5)No Brasil, Brevipalpus phoenicis (Geijskes, 1939) é vetor da leprose na cultura dos citros, doença responsável por significativa redução na produtividade. Objetivou-se avaliar, a capacidade de colonização de B. phoenicis sobre cercas-vivas, quebra-ventos e plantas daninhas, e a potencialidade destas como hospedeiras do vírus da leprose. Realizou-se a colonização das plantas com ácaros procedentes de uma criação-estoque sobre frutos de citros Pêra-rio, para as seguintes plantas hospedeiras intermediárias: Hibiscus sp., Malvaviscus mollis, Grevillea robusta, Mimosa caesalpiniaefolia, Bixa orellana, Euphorbia splendens, Bidens pilosa, Commelina benghalensis, Sida cordifolia, Ageratum conyzoides e Citrus sinensis. Constatou-se que a exceção de E. splendens, todas comportaram-se como hospedeiras do ácaro. Ácaros contaminados, procedentes da criação-estoque, após serem transferidos e confinados em arenas delimitadas nas plantas hospedeiras intermediárias, por um período de 7 dias, não perderam a capacidade de transmitir o vírus para mudas cítricas de Valência e Natal. Ácaros não contaminados que tiveram acesso alimentar por 3 dias nessas mesmas arenas, somente se contaminaram e transmitiram o vírus para mudas de citros, aqueles que se alimentaram sobre: C. benghalensis, S. cordifolia, A. conyzoides, B. pilosa, B. orellana e C. sinensis. Resultados semelhantes foram conseguidos com ácaros criados, por um período de 90 dias, sobre as mesmas plantas hospedeiras intermediárias, inicialmente infestadas com ácaros contaminados também procedentes da criação-estoque.
In Brazil, Brevipalpus phoenicis (Geijskes, 1939) is a vector of the leprosis in the culture of citrus, a disease that causes significant reduction in the productivity. In this work it was evaluated the B. phoenicis capacity of settling on common fence-lives, windbreaks and weeds, and their potentiality as hosts to the leprosis virus. The colonization of the plants was carried out with mites coming from a stock creation on fruits of Pêra-rio citrus, for the following intermediate host plants: Hibiscus sp., Malvaviscus mollis, Grevillea robust, Mimosa caesalpiniaefolia, Bixa orellana, Euphorbia splendens, Bidens pilosa, Commelina benghalensis, Sida cordifolia, Ageratum conyzoides and Citrus sinensis. It was verified that, except for the E. splendens, all species showed to be favorable to the B. phoenicis population growth. Infected mites, coming from the stock creation, that were transferred and confined in delimited arenas in the intermediate host plants for a period of 7 days, did not lose their capacity to transmit the virus for citric seedlings of Valência and Natal. Non infected mites, that had access to feed for 3 days in the same arenas, became only infected and transmitted the virus for citrus seedlings that fed on: C. benghalensis, S. cordifolia, A. conyzoides, B. pilosa, B. orellana and C. sinensis. Similar results were obtained using mites created, for a period of 90 days, on the same intermediate host plants that were initially infested with infected mites coming from the same stock creation.
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Salazar, Laura Cristina Garita. "Relação vírus-vetor-hospedeira no patossistema da leprose dos citros." Universidade de São Paulo, 2013. http://www.teses.usp.br/teses/disponiveis/11/11135/tde-18042013-165710/.
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A leprose dos citros é considerada uma das doenças mais destrutivas da indústria citrícola. O patossistema dessa doença envolve o agente causal o Citrus leprosis virus C, o vetor Brevipalpus phoenicis Geijskes (Acari: Tenuipalpidae) e as plantas hospedeiras. Este vírus com genoma conhecido é membro tipo do gênero Cilevirus. Causa sintomas localizados nas folhas, frutos e caules e está restrito ao continente Americano. Apesar de muitos esforços para se conhecer o patossistema, ainda existem muitas questões pendentes sobre as interações. O presente trabalho teve como objetivo obter informações detalhadas sobre as relações vetorvírus- hospedeiro da leprose citoplasmática, estando dividido em três objetivos: 1. Procurou-se uma planta indicadora padrão que fosse de facil obtenção, manejo e baixo custo, e que expressase em curto tempo os sintomas de CiLV-C e outros vírus transmitidos por Brevipalpus (VTBr); 2. Determinar parâmetros como o período de acesso para aquisição e inoculação do CiLV-C pelo ácaro vetor, o período de retenção do vírus pelo ácaro, avaliação da capacidade das diferentes fases do ácaro de transmitir o vírus e a % de indivíduos de uma população de ácaros colonizando plantas afetadas pela leprose capazes de transmitir o vírus; 3. Avaliar um grande número de espécies de plantas, de diferentes famílias botânicas, quanto à suscetibilidade experimental à infecção pelo CiLV-C, pelo ácaro vetor. A presença de CiLV-C nestes ensaios foi confirmada por testes de ELISA, RT-PCR, microscopia eletrônica de transmissão e imunofluorescência. O feijoeiro comum (Phaseolus vulgaris L.) reage com lesões necróticas locais em apenas cinco dias à inoculação com ácaros virulíferos, podendo-se reduzir para dois dias se as plantas forem incubadas a 28ºC. O cv. ,,Una\" foi selecionado como planta-teste padrão dentre 113 cvs. avaliados. Outros vírus transmitidos por Brevipalpus do tipo citoplasmático (VTBr) como vírus da pinta verde do maracujá (Passion fruit green spot virus PFGSV), vírus da mancha anular de Ligustrum (Ligustrum ringspot virus LigRSV) e mancha verde do hibisco (Hibiscus green spot vírus HGSV) também causaram lesões locais necróticas em feijoeiro. Usando feijão como planta teste e ácaros virulíferos, se determinou o período de acesso à aquisição do vírus-4 h; período de acesso à inoculação do vírus-4h; período de retenção do vírus no ácaro de 12 dias, porcentagem de ácaros virulíferos, colonizando tecidos infectados, transmitirem CiLV-C em até 45%. Os experimentos também confirmaram que todas as etapas de desenvolvimento do ácaro (larvas, proto-deutoninfa e adultos) são capazes de transmitir CiLV-C, inclusive confirmou-se que o macho tem a capacidade de transmissão e que o vírus pode ser adquirido a partir de lesões de folhas, frutos e caules. Não se constatou transmissão transovariana do CiLV-C. Foram testadas 140 espécies, de 45 famílias, dentro das quais 62 espécies de 26 famílias apresentaram lesões localizadas nas folhas. Destas, 46 espécies sintomáticas, o CiLV-C foi detectado em pelo menos um dos testes para sua detecção, confirmando a transmissão. O conhecimento de parâmetros de alimentação, retenção do vírus e porcentagem de ácaros viruliferos na população, além do genoma de hospedeiras suscetíveis ao vírus tem importantes implicações no entendimento da epidemiologia, na quarentena e podem oferecer indícios da origem do CiLV-C.Citrus leprosis (CL), caused by the Citrus leprosis virus C (CiLV-C), is reported only in the American continent. The pathosystem of the CL involves the causal agent, the main vector Brevipalpus phoenicis Geijeskes (Acari: Tenuipalpidae) and the susceptible hosts. For long time only Citrus spp. were considered the sole susceptible host. The entire genome of the CiLV-C was sequenced and a new genus, Cilevirus, was assigned for this virus. CL is characterized by the induction of localized symptoms on the leaves, fruits and stems. Important advances were made recently for the understanding of CL pathosystem, but despite these efforts little is known about details of the virus/vector/host relationship. The present work aimed to cover such deficiencies. In the first place a search of suitable indicator plant was made and the common bean (Phaseolus vulgaris L.) was found to respond with localized necrotic lesions after infestation with viruliferous B. phoenicis in five days and when infested leaves are incubated at 28°C. Furthermore, bean plants are easy and cheap to produce and handle. The black bean cv. ,,IAC Una\" was adopted as a standard test variety, among 113 assayed cultivars of various genetic backgrounds. Common bean plants mite-inoculated with other cytoplasmic-type Brevipalpus-transmitted viruses (BrTVs) [Passion fruit green spot virus (PFGSV), Solanum violaefolium ringspot virus (SvRSV), Ligustrum ringspot virus (LigRSV) and Hibiscus green spot virus (HGSV)] also responded with necrotic local lesions and could serve as test plants for these viruses. Detecion of these viruses were made by RTPCR and/or transmission electron microscopy. Using common bean as test plant, some parameters of the vector/virus relationship were determined: virus acquisition feeding period- 4 h; virus inoculation feeding period- 4h; period of retention of the virus by a single viruliferous mite- at least 12 days; percentage of viruliferous mites from a mites colonizing infected tissues- 45%. The experiments also confirmed that all the developmental stages of the mite (larvae, proto- and deutonymph, adult) as well as males are able to transmit CiLV-C. No transovarial passage of the CiLV-C was registered. The virus can be acquired from lesions of leaves, fruits and stems. To assess the experimental host range of CiLV-C, a large number of plant species were inoculated with B. phoenicis, viruliferous to CiLV-C, under experimental conditions. Of the140 species tested, belonging to 45 families, 62 (of 26 families) produced localized lesions on inoculated leaves. Of these 62 plants producing local lesions, 45 had the presence of CiLV-C confirmed by at least one of the assays to detect the virus (RT-PCR, ELISA, transmission electron microscopy and immunofluorescence). These assays were also used to confirm the presence of CiLV-C in transmission experiments. Although only few non Citrus species were found naturally infected by CiLV-C, present results show that a large number of plant species are susceptible to the virus with implications on the epidemiology, quarantine and the evolution of the citrus leprosis pathosystem.
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Frare, Guilherme Fernando. "Sobrevivência de Colletotrichum acutatum, agente causal da podridão floral dos citros, em plantas daninhas." Universidade de São Paulo, 2012. http://www.teses.usp.br/teses/disponiveis/11/11135/tde-08022012-085923/.
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O Brasil é o maior produtor de laranja do mundo e, embora o cultivo ocorra em todos os estados brasileiros, o Estado de São Paulo é o maior produtor, responsável por 80% da produção nacional. Dentre as doenças que podem limitar a produção dos citros encontra-se a podridão floral do citros (PFC), causada pelo fungo Colletotrichum acutatum J. H. Simmonds. Os sintomas desta doença são caracterizados pela presença de lesões necróticas marrons ou alaranjadas nas pétalas e queda dos frutos recém formados, os cálices e os pedúnculos permanecem retidos nos ramos. Em citros, C. acutatum pode sobreviver aderido à superfície das folhas, na forma de apressório quiescente, por pelo menos um mês. As plantas daninhas podem atuar como hospedeiras alternativas de diversos patógenos, servindo como fontes de inóculo e desempenhando um importante papel na epidemiologia das doenças. O objetivo deste trabalho foi verificar se plantas daninhas, comuns em pomares de citros no Estado de São Paulo, podem servir como fonte de inóculo de C. acutatum para esta cultura. Sete espécies de plantas daninhas foram inoculadas com uma suspensão de conídios de C. acutatum, calibrada a 105 conídios/mL. Após a inoculação, estas foram mantidas em câmara úmida por 36 horas e, em seguida, amostras de todas as plantas foram coletadas e observadas em microscópio óptico para verificar a germinação dos conídios. Trinta, sessenta e noventa dias após as inoculações realizou-se o isolamento de C. acutatum das folhas inoculadas. Para isso, amostras de folhas de cada espécie de planta daninha foram coletadas, desinfestadas superficialmente e transferidas para placas de Petri, onde receberam 70 L de extrato floral de citros sobre o local da inoculação, para estimular a germinação dos apressórios ali presentes. As folhas permaneceram incubadas por 24 horas a 23°C, com fotoperíodo de 12 h. Após esse período, as áreas inoculadas das folhas foram cortadas e transferidas para placas de poliestireno contendo meio de Martin. Após o surgimento das primeiras colônias de C. acutatum, discos de quatro milímetros de diâmetro foram transferidos para meio BDA, para a obtenção de colônias puras. Em seguida foi realizado um teste de patogenicidade em flores de laranja doce de três anos de idade. Os dados de porcentagem de isolamento foram analisados análise de variância e testes não paramétricos. Foram observadas a germinação e a formação de apressórios de C. acutatum na superfície de todas as folhas inoculadas, após 36 horas de câmara úmida. Não houve diferença estatística na sobrevivência de C. acutatum ao longo dos 30, 60 e 90 dias e não foi observado nenhum tipo de sintoma nas folhas inoculadas. C. acutatum foi isolado de todas as plantas daninhas analisadas, embora o tempo de sobrevivência tenha variado em função da espécie de daninha. Todos os isolados obtidos das plantas daninhas apresentaram sintomas típicos de PFC em todas as flores inoculadas. Os resultados obtidos demonstraram que as plantas daninhas avaliadas podem servir como hospedeiras alternativas de C. acutatum, resultando em fonte de inóculo primário e secundário deste patógeno para a cultura do citros.Brazil is the major orange producer in the world, and although the cropping occurs all over the Brazilian States, the São Paulo State is the major producer, responsible for 80% of the national production. Postbloom fruit drop (PFD), caused by the fungus Colletotrichum acutatum J. H. Simmonds is an important disease that can cause yield reduction. The symptoms of this disease are characterized by the presence of brown or orange necrotic lesions in the petals and the drop of young fruits; the calyces and peduncles remain in the branches after fruit drop. In citrus, C. acutatum can adhered to the surface of the leaves, in the form of quiescent appressoria, for at least one month. The weeds can act as alternative hosts of diverse pathogens, serving as inoculum sources and playing an important role in the disease epidemiology. The purpose of this research was to verify if weeds, commons in citrus orchards in São Paulo State, may serve as inoculum source of C. acutatum for this crop. Seven weed species were inoculated with a conidial suspension of C. acutatum, calibrated with 105 conidia/mL. After the inoculation, the weeds were kept in humidity chamber for 36 hours. Samples of all weeds were collected and observed in optical microscope to verify the conidia germination. Thirty, sixty and ninety days after inoculation, C. acutatum was isolated from the inoculated leaves. For this purpose, leaves of each weed species were collected, superficially disinfested and transferred to Petri dishes. The leaves received 70 L of citrus flower extract over the inoculation area to stimulate the appressoria germination. The leaves were incubated for 24 hours at 23°C, with 12 hours of photoperiod. After this period, the inoculated areas were cut and transferred to polystyrene dishes with Martin medium. After the appearance of the first colonies of C. acutatum, discs of four millimeters of diameter were transferred to PDA medium to obtain pure colonies. A pathogenicity test was carried out in three years old sweet orange flowers. The percentage of pathogen isolation was analyzed by variance analysis or non-parametric analysis. Conidia germination and appressoria formation of C. acutatum in all inoculated leaves were observed, after 36 hours of humidity chamber. There was no statistical difference in the C. acutatum survival during 30, 60 e 90 days and no type of symptom was observed in the inoculated leaves. C. acutatum was isolated from every weed analyzed, although the survival period varied among the weed species. Every isolated obtained from the weeds presented typical PFD symptoms in every inoculated flowers. The results showed that weeds can serve as alternative hosts of C. acutatum, contributing in primary and secondary inoculum source of this pathogen to the citrus crop.
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Maia, Ozana Maria de Andrade. "Transmissibilidade da leprose das cercas-vivas, quebra-ventos e plantas daninhas para citros através de Brevipalpus phoenicis (Geijskes, 1939) (Acari: Tenuipalpidae) /." Jaboticabal : [s.n.], 2002. http://hdl.handle.net/11449/91304.
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Orientador: Carlos Amadeu Leite de OliveiraBanca: Francisco Jorge Cividanes
Banca: Wilson Badiali Crocomo
Resumo: No Brasil, Brevipalpus phoenicis (Geijskes, 1939) é vetor da leprose na cultura dos citros, doença responsável por significativa redução na produtividade. Objetivou-se avaliar, a capacidade de colonização de B. phoenicis sobre cercas-vivas, quebra-ventos e plantas daninhas, e a potencialidade destas como hospedeiras do vírus da leprose. Realizou-se a colonização das plantas com ácaros procedentes de uma criação-estoque sobre frutos de citros Pêra-rio, para as seguintes plantas hospedeiras intermediárias: Hibiscus sp., Malvaviscus mollis, Grevillea robusta, Mimosa caesalpiniaefolia, Bixa orellana, Euphorbia splendens, Bidens pilosa, Commelina benghalensis, Sida cordifolia, Ageratum conyzoides e Citrus sinensis. Constatou-se que a exceção de E. splendens, todas comportaram-se como hospedeiras do ácaro. Ácaros contaminados, procedentes da criação-estoque, após serem transferidos e confinados em arenas delimitadas nas plantas hospedeiras intermediárias, por um período de 7 dias, não perderam a capacidade de transmitir o vírus para mudas cítricas de Valência e Natal. Ácaros não contaminados que tiveram acesso alimentar por 3 dias nessas mesmas arenas, somente se contaminaram e transmitiram o vírus para mudas de citros, aqueles que se alimentaram sobre: C. benghalensis, S. cordifolia, A. conyzoides, B. pilosa, B. orellana e C. sinensis. Resultados semelhantes foram conseguidos com ácaros criados, por um período de 90 dias, sobre as mesmas plantas hospedeiras intermediárias, inicialmente infestadas com ácaros contaminados também procedentes da criação-estoque.
Abstract: In Brazil, Brevipalpus phoenicis (Geijskes, 1939) is a vector of the leprosis in the culture of citrus, a disease that causes significant reduction in the productivity. In this work it was evaluated the B. phoenicis capacity of settling on common fence-lives, windbreaks and weeds, and their potentiality as hosts to the leprosis virus. The colonization of the plants was carried out with mites coming from a stock creation on fruits of "Pêra-rio" citrus, for the following intermediate host plants: Hibiscus sp., Malvaviscus mollis, Grevillea robust, Mimosa caesalpiniaefolia, Bixa orellana, Euphorbia splendens, Bidens pilosa, Commelina benghalensis, Sida cordifolia, Ageratum conyzoides and Citrus sinensis. It was verified that, except for the E. splendens, all species showed to be favorable to the B. phoenicis population growth. Infected mites, coming from the stock creation, that were transferred and confined in delimited arenas in the intermediate host plants for a period of 7 days, did not lose their capacity to transmit the virus for citric seedlings of "Valência" and "Natal". Non infected mites, that had access to feed for 3 days in the same arenas, became only infected and transmitted the virus for citrus seedlings that fed on: C. benghalensis, S. cordifolia, A. conyzoides, B. pilosa, B. orellana and C. sinensis. Similar results were obtained using mites created, for a period of 90 days, on the same intermediate host plants that were initially infested with infected mites coming from the same stock creation.
Mestre
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Weiler, Roberto Luis. "Caracterização morfológica, citogenética e molecular de uma população de tangerineiras híbridas de 'Clementina fina' (Citrus clementina Hort. ex Tan.) e 'Montenegrina' (Citrus deliciosa Ten.)." reponame:Biblioteca Digital de Teses e Dissertações da UFRGS, 2006. http://hdl.handle.net/10183/6244.
Full textAbstract:
A produção citrícola se encontra dispersa por todos os continentes e no Brasil, os citros são a produção frutícola de maior volume de produção. A produção de citros de mesa, como as tangerinas, possibilita ao produtor obter maior valor pelo seu produto. O mercado consumidor é ávido por novas variedades e para tanto, um programa de melhoramento deve estar sempre em busca de genótipos que atendam ao mercado consumidor, bem como a cadeia produtiva. Na Estação Experimental Agronômica da Universidade Federal do Rio Grande do Sul, está localizada uma população de tangerineiras híbridas oriundas do cruzamento da tangerineira ‘Clementina Fina’ (Citrus clementina Hort. ex Tan.) e ‘Montenegrina’ (Citrus deliciosa Ten.) a qual foi caracterizada neste estudo, avaliando-se características morfológicas de acordo com os descritores propostos pelo International Board for Plant Genetic Resources, além da identificação da época de maturação, viabilidade de pólen, número cromossômico e caracterização molecular, utilizando marcadores do tipo microssatélites. Através da análise morfológica foi possível distinguir todas as 96 plantas avaliadas, porém não foi possível agrupar a F1 em grupos distintos de cada um dos genitores. A época de maturação de frutos das plantas se concentra entre a primeira quinzena de abril até a primeira quinzena de agosto. Todas as plantas analisadas apresentaram um alto grau de viabilidade de pólen, variando entre 79,04 e 98,08 %. Todas as plantas avaliadas são diplóides com um número cromossômico de 2n=18. Utilizando 12 pares de primers de microssatélites foi possível diferenciar 90 acessos do estudo, e agrupar a F1 em indivíduos mais próximos do genitor feminino e do genitor masculino. O PIC (Conteúdo de Informação de Polimorfismo) dos primers variou de 0,27 a 0,65. Não foi possível estabelecer uma relação entre a caracterização utilizando marcadores morfológicos e a caracterização utilizando marcadores moleculares.Citrus production is widespread all over the world and in Brazil it represents the major volume of fruit production. Production of fresch fruit, as tangerines, allow the farmer to obtain a better value for the product. The consuming market is keen for new varieties and a breeding program should be always searching for genotypes that satisfy the market as well as the productive chain. At the Agronomic Experimental Station of Federal University of Rio Grande do Sul there is a population of hybrid tangerines, as result of crosses between ‘Clementina Fina’ (Citrus clementina Hort. ex Tan.) and ‘Montenegrina’ (Citrus deliciosa Ten.). In this study, this population was characterized using the morphological descriptors proposed by the International Board for Plant Genetic, besides other characteristics such as ripening period, pollen viability, chromosome number and a molecular characterization with SSR markers. It was possible to distinguish all the 96 evaluated plants by the morphological descriptors, but it was not possible to separate the F1 in groups distinct from the parents. Ripening occurred between mid April and mid August. All the analyzed plants had a high pollen viability, ranging from 79.04% to 98.08%. All plants are diploid, with 2n = 18. By using 12 pairs of primers it was possible to differentiate 90 of the analyzed accessions and group F1 individuals closer to the female and male parents. The PIC (polymorphism information content) ranged from 0.27 and 0.65. It was not possible to establish a relation between the morphological and the molecular characterizations. 1Master of Science dissertation in Agronomy, Faculdade de Agronomia, Universidade Federal do Rio Grande do Sul, Porto Alegre, RS, Brazil. (67p.) March, 2006.
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Son, Christina. "Use of tissue culture and molecular techniques to assess variation within Phytophthora citrophthora and screen for disease resistance in its citrus host." Adelaide Thesis (Ph.D.) -- University of Adelaide, 1992. http://hdl.handle.net/2440/21624.
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Son, Christina. "Use of tissue culture and molecular techniques to assess variation within Phytophthora citrophthora and screen for disease resistance in its citrus host." Thesis, Adelaide Thesis (Ph.D.) -- University of Adelaide, 1992. http://hdl.handle.net/2440/21624.
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Barnhart, Erin Leslie. "Engaging Global Service: Organizational Motivations for and Perceived Benefits of Hosting International Volunteers." PDXScholar, 2012. https://pdxscholar.library.pdx.edu/open_access_etds/372.
Full textAbstract:
An increasingly popular way for global citizens to contribute to communities around the world is through international volunteering. In tandem with this growing trend, academic research in the field has increased to explore the goals, motivations, and impacts of international service on volunteers, host communities, and volunteer-sending organizations. One of the larger gaps in our understanding of global civic engagement though is the specifics of how and why, as well as the overall impact of international service on, host organizations that seek and/or accept international volunteers. Using an exploratory research design to collect and analyze survey data and open-ended email inquiry responses from almost 250 organizational representatives in 50+ countries, this dissertation expands the breadth and depth of knowledge on the relationship between host organizations and international volunteers. Findings include a broad and varied range of potential motivations for hosting international volunteers, from direct benefits to the host organization like leveraging organizational capacity to benefits extended to the broader community and volunteers themselves such as providing opportunities for cross-cultural interaction. In addition, host organization characteristics and opinions were compared between two global regions - Africa and Asia - and statistically significant relationships identified between characteristics and opinions of host organizations and their reported satisfaction with international volunteers. This study contributes new data on and from organizations that host international volunteers. Research findings also support and expand the field's understanding of international volunteer engagement as it relates specifically to organizational capacity and social capital theory.
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Wear, Andrew. "High-tech hot spot or sleepy backwater? : innovation and the importance of networks /." Connect to thesis, 2008. http://repository.unimelb.edu.au/10187/5741.
Full textAbstract:
This paper draws on evidence from Victoria to examine why more innovation takes place in some areas than in others. In so doing, it explores the relationship between innovation and networks.Despite a large number of recent government policy statements on innovation, there has been very little attention paid to the spatial dimensions of innovation.
The literature on innovation increasingly points to the important role played by local and regional networks in driving innovation. Innovation is the result of the production, use and diffusion of knowledge, and this demands collaboration involving networks of individuals, organisations and institutions.
To test the theory of a connection between networks and innovation across regional Victoria, patent data is used as a proxy measure for innovation. This data is then cross-referenced with various social and economic data sets.
The analysis reveals that innovation in Victoria is substantially concentrated in ‘hot spots’ such as inner Melbourne. In some parts of Victoria very little innovation takes place at all.
This research has found that all things being equal, more innovation will take place in those areas in which there is a greater density of informal networks. However, not all types of networks are positive, and they are more important in provincial areas than in big cities. Innovation clearly has a spatial aspect, and innovation policy needs to give particular attention to the requirements of provincial areas.
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Kreofsky, Tess Marie. "Isn’t Citizen Science a Hoot? A Case-study Exploring the Effectiveness of Citizen Science as an Instrument to Teach the Nature of Science through a Local Nocturnal Owl-Monitoring Project." PDXScholar, 2015. https://pdxscholar.library.pdx.edu/open_access_etds/2645.
Full textAbstract:
Citizen science projects present a distinctive opportunity for professional and volunteer scientists to coordinate their efforts to gather unique sets of data that can benefit the scientific and local communities. These projects are assumed to be an effective educational tool to teach nature of science (NOS) to participants (Brossard, Lewenstein, Bonney, 2005). This case study evaluates the effectiveness of participation in a citizen science project as a way to learn about NOS. Through enhancement of the Tryon Creek Owl Monitoring Project the researcher reviewed the characteristics of a citizen science project that were thought to be necessary to impact the volunteers' knowledge of NOS. The study also explored the benefits and limitations to organizing the citizen science protect using the principles of action research. Analysis of participants' knowledge and the effectiveness of active research theory, was evaluated through pre- and post- questionnaires and interviews. Although volunteers were able to explore the core themes of NOS through actively engaging in the scientific process, they did not experience a statistically significant change in their demonstration of understanding. For a multitude of reasons, participants had a positive experience with the presence of an embedded researcher within the project. This case study supports the use of active research as a guide to ensure that within each project the needs of both the scientific community and the volunteer scientists are met.
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Ferreira, Cristiano Barbalho [UNESP]. "Caracterização fenotípica e funcional de mutantes da bactéria fitopatogênica Xanthomonas citri subsp. citri." Universidade Estadual Paulista (UNESP), 2009. http://hdl.handle.net/11449/92707.
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Fundecitrus
Dentro da comercialização de frutas, a citricultura é a mais importante. Representa para muitos países, dentre eles, os EUA e o Brasil, uma importante atividade econômica. Porém, esta atividade, vem sofrendo com inúmeras doenças e/ou pragas como a doença do Cancro Cítrico Asiático causada pela bactéria Xanthomonas citri subsp. citri (X. citri). Deste modo, com o objetivo do estudo do genoma funcional da X. citri, um banco de mutantes deste microorganismo foi obtido por meio de inserção aleatória do transposon Tn5, nas quais foram selecionados 53 mutantes que apresentaram, de forma superficial, alterações fenotípica em relação à X. citri selvagem. Para uma avaliação mais precisa, eles passaram por uma nova confirmação de suas alterações fenotípicas, onde foram inoculados em folhas de Citrus sinensis (Laranjeira pêra-Rio) e Citrus limonia (limoeiro cravo) e monitorados durante 16 dias, e aqueles que apresentaram as maiores alterações em relação à selvagem, tiveram confeccionadas para si curvas de crescimento in vivo. Conseguiu-se, desta forma, avaliar quantitativamente o processo patogênico, relacionar seus sintomas com dados numéricos e ainda descobrir detalhes até então não conhecidos. O mapeamento, dos respectivos loci mutados, foi realizado por seqüenciamento de DNA a partir do transposon, demonstrando que a metodologia empregada para a obtenção dos mutantes foi eficiente, conseguiu também revelar diversas proteína ainda hipotéticas, e outras, até então, não considerados como implicados no processo patogênico, como, uma Integrase, Fe-S oxidoredutase, Helicase IV, Receptor Dependente de Ton-B, entre outros
Concerning the commercialization of fruits, the citrus production is the most important. It represents for many countries, amongst them, U.S.A. and Brazil, an important economic activity. However, this activity has been suffering with many illnesses and/or plagues as the illness from the Asiatic citrus canker caused by the Xanthomonas citri subsp. citri bacterium (X. citri). In this way, from a bank of mutants of X. citri, gotten by means of random insertion of commercial one derived from transposon Tn5, had been selected 53 mutants that had presented, of superficial form, some type of phenotype alteration in relation to the wild X. citri. To a more necessary evaluation, each one of them passed for a new confirmation of its phenotype alterations, where they had been inoculated in leafs of Citrus sinensis ('Pera' sweet orange) and Citrus limonia ('Rangpur' lime) and monitored during 16 days, and those that had presented the biggest alterations in relation to the savage, had confectioned for itself in planta growth curves. We obtain, in such a way, to evaluate quantitatively the pathogenic process, to relate its symptoms with numerical data and still to discover not known details until then. The mapping of respective locus mutated was carried through by sequencing of DNA from transposon, demonstrating that the methodology used for the attainment of the mutants was efficient and still to disclose diverse genes still hypothetical, and others, until then, not considered as implied in the pathogenic process, as, Integrase, Fe-S oxidoredutase, Helicase IV, TonB-dependent receptor, among others
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Burón, Moles Gemma. "Molecular, biochemical and pathological approaches to unravel the defence responses of apples and oranges against Penicillium spp." Doctoral thesis, Universitat de Lleida, 2014. http://hdl.handle.net/10803/145981.
Full textAbstract:
Despite the current use of chemical fungicides, Penicillium digitatum and P. expansum still are the most devastating pathogens of orange and apple fruit, respectively. These wound pathogens can infect fruits through injuries caused during harvest and postharvest handling, which annually lead to large economic losses worldwide. To obtain new rational and environmental friendly control alternatives, it is fundamental to understand these pathosystems, taking into account both, fungal pathogenicity mechanisms and host defence responses. In this thesis, by using gfp-tagged strains we have visualized the infection and have been confirmed these strains as a good tool to perform interaction and pathogen colonization studies. Once compatibility relationships were established, we have characterized the H2O2 effect on pathogens and hosts. Our findings suggests that H2O2 produced in fruit in response to abiotic and biotic stresses could be involved in signalling different functions linked with host resistance processes, rather than inhibiting the P. digitatum and P. expansum spore germination. As a high-throughput molecular method a proteomic approach was used to study the apple protein changes (both, abundance and oxidation) in response to abiotic (wounding) and biotic (P. expansum and P. digitatum) stresses. We have emphasized the findings related to those protein changes specifically induced in response to P. digitatum as non-host pathogen in apples. Among abundance changes we have identified Mal d 1.03E and EF-Tu, as well as oxidative changes in ACC oxidase and glutamine synthetases. Finally, we also have determined a low correlation between the transcript and protein abundances of some selected genes involved in wound and pathogen responses. Only Mal d 1.03E showed a significant correlation at the transcript and protein level. Knowledge obtained in this thesis could be an important step towards the improvement of disease control strategies, not only in these studied pathogens, but also in other important postharvest diseases.
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Eriksson, Niklas, and Niklas Gustafsson. "Framträdande diskurser om staden hos olika aktörer inom planeringen : En analys av Storgatans omvandling till sommargågata i Linköping." Thesis, Linköpings universitet, Institutionen för tema, 2020. http://urn.kb.se/resolve?urn=urn:nbn:se:liu:diva-166258.
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This study aims to identify and describe discourses about the city and how they appear from different stakeholder’s views regarding the transformation of Storgatan to a pedestrian street during the summer in Linköping city. This creates a deeper insight into how work towards sustainability become visible in the planning of the inner city. The study uses a discourse analysis of interviews and texts to study which identified discourses about the city become apparent. Conflicts that appear regarding the transformation of Storgatan is also analyzed. Results show that while different stakeholders follow similar discourses about the city regarding their ideal, they are also expressed in different ways and can relate to different meaning. The conclusion is that the different stakeholders largely agree that the implementation of a pedestrian street on Storgatan is something positive, and that a good foundation for an eventual future permanent implementation of the pedestrian street is shown.Studien syftar till att identifiera och beskriva vilka diskurser om staden som blir framträdande hos olika aktörer i samband med Storgatans omvandling till sommargågata och därigenom få en fördjupad förståelse för hur arbetet mot hållbarhet tas i uttryck i innerstadsplaneringen. Det görs via en diskursanalys av intervjuer och texter, där tidigare identifierade diskurser om staden används. Samtidigt undersöks även vilka konflikter som finns kring Storgatans omvandling. Resultaten visar att de olika aktörerna har liknande diskurser kring deras vision av stadens utformning, dock tar de sig i uttryck på olika sätt. Konflikter och utmaningar som uppstår kopplat till detta gäller främst trafiken i området där den största utmaningen är kollektivtrafikens omflyttning. Slutsatsen är att de olika aktörerna som varit delaktiga i studien generellt sett ställer sig positiva till gågatans implementering och det också finns en god grund för en eventuell framtida permanent implementering av den.
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Poiroux, Florine. "Etude des effets des facteurs de l'environnement sur la concentration en caroténoïdes dans la pulpe de clémentines : citrus clementina hort. ex tan." Corte, 2011. http://www.theses.fr/2011CORT0024.
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Les fruits représentent une source majeure de vitamines et de métabolites secondaires. Bien qu'il y ait débat sur les mécanismes d'action des métabolites secondaires sur la santé humaine, il y a un consensus général sur le fait que les avantages santé des fruits sont en partie attribuables à leur forte concentration en vitamines et métabolites secondaires. Les caroténoïdes, et principalement les caroténoïdes précurseurs de la vitamine A (ß-carotène, α-carotène et ß-cryptoxanthine) sont des composants essentiels au régime alimentaire de l'Homme. Un certain nombre d'observations suggèrent qu'ils jouent des rôles dans la prévention de certaines maladies. Les agrumes représentent une source majeure de caroténoïdes à la fois par leur concentration et leur diversité. Dans le but de produire des fruits d'agrumes à teneurs augmentées ou garanties en caroténoïdes, nous avons testé deux hypothèes. La première concernait l'implication de la disponiblilité en carbone dans la synthèse et l'accumulation des caroténoïdes et la deuxième le rôle du stress oxydatif ou des variations de statut rédox sur cette biosynthèse. (. . . /. . . )Fruits are a major source of vitamins and secondary metabolites. Although there is a debate about the way secondary metabolites impact human health, there is a general consensus that the much praised health benefits of fruits are, at least partially, attributable to their high concentrations in vitamins and secondary metabolites. Carotenoids, and in particular carotenoids endowed with provitamin A (β-carotene, α- carotene and β-cryptoxanthine) are vital components of the human diet. Many observations suggest that they have an impact in preventing of diseases. Citrus fruits are a major source of carotenoids by both concentration and diversity. With the objective to produce citrus fruit with increased or guarenteed amounts of carotenoids, we tested two hypotheses. The first is that sugar supply influences biosynthesis and accumulation of carotenoids, and the second, is that oxidative stress or the associated variations in redox status in this biosynthesis. (. . . /. . . )
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Pekas, Apostolos. "Factors affecting the biological control of California red scale Aonidiella aurantii (Hemiptera: Diaspididae) by Aphytis (Hymenoptera: Aphelinidae) in eastern Spain citrus: host size, ant activity, and adult parasitoid food sources." Doctoral thesis, Universitat Politècnica de València, 2011. http://hdl.handle.net/10251/10293.
Full textAbstract:
California red scale (CRS), Aonidiella aurantii (Maskell) (Hemiptera: Diaspididae), one of the most important pests of citrus worldwide, began to cause damages in eastern Spain in 1986. The main biological control agents of A. aurantii in this zone are the native parasitoid A. chrysomphali (Mercet) and the introduced A. melinus DeBach (both Hymenoptera: Aphelinidae). Nevertheless, the control they exert is insufficient. In order to improve the biological control of A. aurantii we studied several biotic factors that may affect the efficiency of A. chrysomphali and A. melinus in the field. More concretely, we studied the spatial and temporal variation in the scale size, the host sizes used by A. chrysomphali and A. melinus as well as the influence of host size on various parasitoid traits. Moreover, we studied the foraging ecology and the effect of the ants native to the Mediterranean on the populations of the scale and, finally, the nutritional state and food sources used by adult A. melinus in the field.
In the field, the body size of A. aurantii varied with plant substrate, locality, time of the year, and probably, with the nutritional state of the host plant. Plant substrate was found to substantially influence the body size of A. aurantii with scales being significantly larger on fruits that on leaves or twigs. Another important source of variation for A. aurantii size was geographic location since significant differences were found among orchards. Moreover, significant seasonal variation in the body size of A. aurantii was observed; body sizes were smaller during summer and autumn, apparently due to the effect of temperature. Finally, a positive relationship between the content of potassium in leaves and scale size was observed. From all the above factors, temperature related seasonal variation had the most profound effect on A. aurantii size.
Aphytis chrysomphali and A. melinus used different sizes of A. aurantii in the field.Pekas, A. (2011). Factors affecting the biological control of California red scale Aonidiella aurantii (Hemiptera: Diaspididae) by Aphytis (Hymenoptera: Aphelinidae) in eastern Spain citrus: host size, ant activity, and adult parasitoid food sources [Tesis doctoral no publicada]. Universitat Politècnica de València. https://doi.org/10.4995/Thesis/10251/10293
Palancia
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Ferreira, Cristiano Barbalho. "Caracterização fenotípica e funcional de mutantes da bactéria fitopatogênica Xanthomonas citri subsp. citri /." Jaboticabal : [s.n.], 2009. http://hdl.handle.net/11449/92707.
Full textAbstract:
Resumo: Dentro da comercialização de frutas, a citricultura é a mais importante. Representa para muitos países, dentre eles, os EUA e o Brasil, uma importante atividade econômica. Porém, esta atividade, vem sofrendo com inúmeras doenças e/ou pragas como a doença do Cancro Cítrico Asiático causada pela bactéria Xanthomonas citri subsp. citri (X. citri). Deste modo, com o objetivo do estudo do genoma funcional da X. citri, um banco de mutantes deste microorganismo foi obtido por meio de inserção aleatória do transposon Tn5, nas quais foram selecionados 53 mutantes que apresentaram, de forma superficial, alterações fenotípica em relação à X. citri selvagem. Para uma avaliação mais precisa, eles passaram por uma nova confirmação de suas alterações fenotípicas, onde foram inoculados em folhas de Citrus sinensis (Laranjeira pêra-Rio) e Citrus limonia (limoeiro cravo) e monitorados durante 16 dias, e aqueles que apresentaram as maiores alterações em relação à selvagem, tiveram confeccionadas para si curvas de crescimento in vivo. Conseguiu-se, desta forma, avaliar quantitativamente o processo patogênico, relacionar seus sintomas com dados numéricos e ainda descobrir detalhes até então não conhecidos. O mapeamento, dos respectivos loci mutados, foi realizado por seqüenciamento de DNA a partir do transposon, demonstrando que a metodologia empregada para a obtenção dos mutantes foi eficiente, conseguiu também revelar diversas proteína ainda hipotéticas, e outras, até então, não considerados como implicados no processo patogênico, como, uma Integrase, Fe-S oxidoredutase, Helicase IV, Receptor Dependente de Ton-B, entre outrosAbstract: Concerning the commercialization of fruits, the citrus production is the most important. It represents for many countries, amongst them, U.S.A. and Brazil, an important economic activity. However, this activity has been suffering with many illnesses and/or plagues as the illness from the Asiatic citrus canker caused by the Xanthomonas citri subsp. citri bacterium (X. citri). In this way, from a bank of mutants of X. citri, gotten by means of random insertion of commercial one derived from transposon Tn5, had been selected 53 mutants that had presented, of superficial form, some type of phenotype alteration in relation to the wild X. citri. To a more necessary evaluation, each one of them passed for a new confirmation of its phenotype alterations, where they had been inoculated in leafs of Citrus sinensis ('Pera' sweet orange) and Citrus limonia ('Rangpur' lime) and monitored during 16 days, and those that had presented the biggest alterations in relation to the savage, had confectioned for itself in planta growth curves. We obtain, in such a way, to evaluate quantitatively the pathogenic process, to relate its symptoms with numerical data and still to discover not known details until then. The mapping of respective locus mutated was carried through by sequencing of DNA from transposon, demonstrating that the methodology used for the attainment of the mutants was efficient and still to disclose diverse genes still hypothetical, and others, until then, not considered as implied in the pathogenic process, as, Integrase, Fe-S oxidoredutase, Helicase IV, TonB-dependent receptor, among others
Orientador: Maria Inês Tiraboschi Ferro
Coorientador: Julio Cezar Franco de Oliveira
Banca: Manoel Victor Franco Lemos
Banca: Mariana Carina Frigieri
Mestre
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Marques, Rodrigo Neves. "Cigarrinhas (Hemiptera: Cicadellidae) potenciais vetoras de um fitoplasma (grupo 16SrlX) associado a sintomas de Huanglongbing dos citros, suas plantas hospedeiras e quantificação do patógeno." Universidade de São Paulo, 2011. http://www.teses.usp.br/teses/disponiveis/11/11146/tde-02052011-092707/.
Full textAbstract:
O Huanglongbing (HLB) é uma das mais temidas doenças da citricultura mundial, associada a bactérias do gênero Candidatus Liberibacter, que foram detectadas no Brasil em 2004. Em 2008, detectou-se outra bactéria associada a sintomas de HLB no Estado de São Paulo, que foi caracterizada como sendo um fitoplasma do grupo 16 SrIX. Fitoplasmas são molicutes fitopatógenos restritos ao floema de plantas, disseminados por insetos vetores. O presente trabalho buscou identificar cigarrinhas potencialmente vetoras do fitoplasma associado ao HLB e plantas hospedeiras desses insetos, bem como desenvolver uma técnica de quantificação de DNA desse patógeno em insetos e plantas. Amostragens de cigarrinhas foram realizadas quinzenalmente por 12 meses em dois pomares de laranja com histórico de ocorrência do fitoplasma 16SrIX na região norte do Estado de São Paulo, usando-se armadilhas adesivas amarelas em duas alturas (0,3 e 1,5 m) da copa de árvores cítricas, e rede de varredura na vegetação espontânea. Dados faunísticos identificaram uma espécie de Agalliinae (Agallia albidula Uhler) e três de Deltocephalinae, [Balclutha hebe (Kirkaldy), Planicephalus flavicosta (Stål) e Scaphytopius (Convelinus) marginelineatus (Stål)], como os cicadelídeos (Hemiptera: Cicadellidae) mais abundantes e frequentes nas áreas estudadas. Essas espécies predominaram na amostragem com rede de varredura e na menor altura de coleta com armadilhas adesivas, indicando comportamento de alimentação em vegetação rasteira. Com observações visuais, verificou-se associação das espécies com certas plantas invasoras, e influência da composição florística da vegetação rasteira sobre a abundância das cigarrinhas. S. marginelineatus e P. flavicosta ocorreram com maior frequência em Sida rhombifolia L. e Althernantera tenella Colla, respectivamente, enquanto que A. albidula foi predominante em Conyza bonariensis (L.) Cronq., e B. hebe ocorreu exclusivamente em gramíneas, principalmente Panicum maximum Jacq.. Plantas invasoras amostradas nas áreas foram testadas para a presença do fitoplasma 16SrIX, porém sem resultados positivos. No entanto, amostras de campo da cigarrinha S. marginelineatus foram positivas por PCR e sequenciamento para o referido fitoplasma. Indivíduos de S. marginelineatus criados em laboratório e mantidos por um período de acesso à aquisição de 72 h em citros infectado com o fitoplasma 16SrIX, foram capazes de transmití-lo para citros, após 21 dias de latência, porém com baixa eficiência (0,5%). Por meio de PCR quantitativo desenvolvido para esse fitoplasma, verificou-se baixo título do patógeno tanto em S. marginelineatus, quanto em plantas cítricas infectadas, o que pode explicar, pelo menos em parte, a baixa eficiência de transmissão pelo inseto tendo citros como fonte. Isto sugere a existência de outros hospedeiros mais adequados como fontes de inóculo para aquisição do fitoplasma por S. marginelineatus ou outro vetor ainda desconhecido.Huanglongbing (HLB) is a severe citrus disease associated to phloemlimited bacteria in the genus Candidatus Liberibacter, which were detected in Brazil in 2004. In 2008, another bacterium was found in association with HLB symptom in the São Paulo State, and characterized as a phytoplasma belonging to 16SrIX group. Phytoplasmas are vector-borne phytopathogenic mollicutes that inhabit plant sieve elements. The goals of this study were to identify potential leafhopper vectors of the HLB-associated phytoplasma and their host plants, as well as to establish a real-time PCR procedure for pathogen quantification in vectors and plants. Leafhoppers were sampled fortnightly for 12 months by yellow sticky cards placed at two heights (0.3 and 1.5 m) on the citrus tree canopy and by sweep net in the ground vegetation of two sweet orange groves with history of infection by the 16SrIX phytoplasma, in the northern region of São Paulo State. Faunistic analyses indicated 1 Agalliinae (Agallia albidula Uhler) and 3 Deltocephalinae [Balclutha hebe (Kirkaldy), Planicephalus flavicosta (Stål) e Scaphytopius (Convelinus) marginelineatus (Stål)] species that were the most abundant and frequent leafhoppers (Hemiptera: Cicadellidae) in the experimental areas. These species predominated in sweep net and in sticky traps catches at 0.3 m above soil, showing that they inhabit the ground vegetation. Visual observations indicated a strong association of leafhopper species with some weeds and the influence of weed species composition on leafhopper abundance in the ground vegetation. S. marginelineatus and P. flavicosta were more frequent on Sida rhombifolia L. and Althernantera tenella Colla, respectively, while A. albidula was observed more often on Conyza bonariensis (L.) Cronq., and B. hebe occurred solely on grasses, more abundantly on Panicum maximum Jacq. Fourteen weed species sampled in the area were PCR tested for infection by the 16SrIX phytoplasma, but none was found infected. Nevertheless, 3 out of 30 field-collected samples (10 adults per sample) of S. marginelineatus tested positive for this phytoplasma by PCR and sequencing. Healthy lab-reared adults of S. marginelineatus were able to transmit inefficiently (0,5%) the 16SrIX phytoplasma to healthy citrus after a 72-h acquisition access period on infected citrus plants followed by a 21-day latent period on S. rhombifolia plants. By using the qPCR method developed for this phytoplasma, a very low pathogen titer was found both in S. marginelineatus and in infected citrus plants, which may explain, at least partially, the low transmission efficiency by this vector using citrus as a source plant. It also suggests that existence of alternative hosts that might be more adequate as inoculum sources for phytoplasma acquisition and spread by S. marginelineatus or another vector yet to be discovered.
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Matibane, Luvuyo P. "Improving service delivery through partnerships between local government, civil society and the private sector : a case study of Imizamo Yethu." Thesis, Stellenbosch : University of Stellenbosch, 2010. http://hdl.handle.net/10019.1/5253.
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Thesis (MA (Public and Development Management))--University of Stellenbosch, 2010.ENGLISH ABSTRACT: Developmental local government places emphasis on the importance of partnerships between local government and various stakeholders such as community-based organisations, non-governmental organisations and private sector organisations delivering services to communities. The focus of this thesis is on a service delivery improvement plan for Imizamo Yethu in Hout Bay, Cape Town, a poor Black informal settlement alongside a well-established and affluent White suburb. There is severe lack of service delivery in that community and the study has sought to suggest a solution that would address the appalling situation in which the people of Imizamo Yethu live. It seeks to respond to the question: How can partnerships between civil society organisations, local government and the private sector improve service delivery in Imizamo Yethu? The main research objectives were to determine how local government, business and civil society organisations can deliver services; to establish whether there were any partnerships between local government, civil society and the private sector in Imizamo Yethu; to describe the activities of role players in Imizamo Yethu; to identify areas that require partnership between these role players; to generate information for future research that will enable the community of Imizamo Yethu to address their problems; and to make recommendations on how service provision could be improved by establishing partnerships between local government, civil society and the private sector. Service provision is a complex exercise that needs different skills and strategies. Local government alone cannot win the battle of service delivery. What is needed is the collaboration of different role players using their different and unique capabilities. Partnerships between local government, civil society organisations and the private sector can be an effective alternative model of service provision. The study therefore focuses on improving partnerships between local government, civil society and business in Imizamo Yethu. While many civil society organisations, business organisations and local government departments are involved in service delivery and development in Imizamo Yethu, these organisations operate in isolation from each other. This makes it virtually impossible for them to make a dent in service delivery challenges. Through partnerships, local government, civil society and the private sector could wszssork together to mitigate the situation in the particular community. Forums by means of which local government, civil society organisations and business can work together should therefore be formed. Such forums could assist in terms of devising a strategy to provide services, and disseminate information. The study examines the level of service delivery and partnerships in Imizamo Yethu. It was found that there is both lack of service delivery and lack of partnership between the local government, which is the City of Cape Town, civil society and the private sector. It is recommended that community service delivery be established, with dissemination of information by the City of Cape Town by means of a communication strategy aimed at informing the community about such service delivery.
AFRIKAANSE OPSOMMING: Ontwikkelingsgerigte plaaslike regering beklemtoon die belangrikheid van vennootskappe tussen die plaaslike owerheid en verskillende belanghebbers soos gemeenskapsgebaseerde organisasies, nie-regeringsorganisasies en organisasies in die private sektor wat dienste aan gemeenskappe lewer met die oog op ontwikkeling. Die tesis fokus op ‘n verbeterde diensleweringsplan vir Imizamo Yethu te Houtbaai, Kaapstad, ’n arm, informele Swart nedersetting aangrensend aan ‘n goed gevestigde en welgestelde wit voorstad. Die gemeenskap ondervind ’n ernstige gebrek aan dienslewering en die studie het gepoog om ’n oplossing aan die hand te doen om die haglike omstandighede waarin die inwoners van Imizamo Yethu bestaan, aan te spreek. Dit het probeer om die vraag met betrekking tot hoe vennootskappe tussen organisasies van die burgerlike samelewing, die regering en die private sektor dienslewering aan Imizamo Yethu kan verbeter. Die hoof navorsingsdoelwitte was om vas te stel hoe plaaslike regering en organisasies binne die sakelewe en burgerlike samelewing dienste kan lewer; om vas te stel of daar enige vennootskappe tussen die plaaslike owerheid, die burgerlike samelewing en die private sektor in Imizamo Yethu bestaan; om die aktiwiteite van rolspelers in Imizamo Yethu te beskrywe; om areas waarbinne ’n vennootskap tussen sodanige rolspelers benodig word, te identifiseer; om inligting vir toekomstige navorsing wat die gemeenskap in Imizamo Yethu in staat sal stel om hul probleme aan te spreek, te genereer; en om voorstelle aan die hand te doen oor hoe dienslewering deur die daarstelling van vennootskappe tussen die plaaslike bestuur, die burgerlike samelewing en die private sektor verbeter kan word. Die lewering van dienste is ‘n ingewikkelde oefening wat verskillende vaardighede en strategieë verg. Die regering is nie in staat om die stryd om dienste te lewer, op sy eie te stry nie. Wat vereis word, is samewerking van die kant van verskillende rolspelers wat hul onderskeie en unieke vermoëns inspan. Vennootskappe tussen die plaaslike owerheid, organisasies binne die burgerlike samelewing en die private sektor kan ’n effektiewe alternatiewe model vir dienslewering wees. Die studie is dus ook gerig op die verbetering van vennootskappe tussen die plaaslike owerheid, die burgerlike samelewing en die sakelewe in Imizamo Yethu. Terwyl vele organisasies binne die burgerlike samelewing en sakelewe en plaaslike regeringsdepartemente reeds by dienslewering en ontwikkeling in Imizamo Yethu betrokke is, tree hierdie organisasies afsonderlik op. Hul geïsoleerdheid maak dit haas onmoontlik om die uitdagings verbonde aan dienslewering die hoof te bied. Vennootskap tussen die plaaslike owerheid, die burgerlike samelewing en die private sektor kan egter samewerking bewerkstellig om omstandighede binne die besondere gemeenskap te verlig. Forums waarbinne samewerking tussen die plaaslike owerheid, die burgerlike gemeenskap en die sakelewe moontlik is, behoort dus geskep te word. Sulke forums kan die ontwikkeling van ’n strategie vir dienslewering en die verspreiding van inligting aanhelp. Die studie het die vlak van dienslewering en vennootskap in Imizamo Yethu ondersoek. ’n Gebrek aan dienslewering sowel as aan vennootskap tussen die plaaslike owerheid, naamlik die Stad Kaapstad, die burgerlike samelewing en die private sektor is gevind. Die voorstel is dat die Stad Kaapstad dienslewering aan die gemeenskap instel, tesame met ‘n inligtingstrategie wat daarop gemik is om die gemeenskap oor sodanige dienslewering in te lig.
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Zimba, Kennedy Josaya. "Using the larval parasitoid, Agathis bishopi (Nixon) (Hymenoptera: Braconidae), for early detection of false codling moth, Thaumatotibia leucotreta (Meyrick) (Lepidoptera: Tortricidae) infested fruit." Thesis, Rhodes University, 2015. http://hdl.handle.net/10962/d1017186.
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Thaumatotibia leucotreta (Meyrick) (Lepidoptera: Tortricidae) is one of the major citrus pests of economic importance for South Africa’s citrus industry. It is endemic to Africa, and therefore a phytosanitary pest with zero tolerance by most export markets. The cryptic nature of T. leucotreta makes visual inspection an inefficient method for detecting neonate larvae in fruit in the packhouse. Therefore, a more accurate method for sorting infested fruit at the packhouse, particularly for newly infested fruit could ensure market access. A recent study showed that fruit infested by T. leucotreta emit a chemical profile different from that of a healthy fruit. Several studies provide evidence that parasitoids locate their hosts feeding on fruit by exploiting the novel chemical profiles produced due to host herbivory. The aim of this study was to evaluate the potential of using the naturally occurring behaviour of a larval parasitoid Agathis bishopi (Nixon) (Hymenoptera: Braconidae) for detection of T. leucotreta infested fruit, by determining which compound in infested fruit is attractive to parasitoids. Ytube olfactometer and flight-tunnel bioassays with healthy and T. leucotreta infested fruit showed a significantly stronger response of A. bishopi female parasitoids to infested fruit. Among the volatile compounds associated with T. leucotreta infested fruit, D-limonene elicited the strongest attraction to A. bishopi female parasitoids. Attraction of mated A. bishopi female parasitoids to T. leucotreta infested fruit and D-limonene significantly increased after oviposition experience. Behavioural responses of A. bishopi female parasitoids that were associated with T. leucotreta infested fruit were investigated to determine which behaviours are distinct and interpretable. Probing and oviposition behaviours were the most noticeable and were only elicited on infested fruit when parasitoids contacted T. leucotreta frass, indicating that chemical compounds in frass are short-range cues used for final host location. Since production of D-limonene by fruit is elevated due to herbivory by different pests including mechanical injury on fruit, response of A. bishopi female parasitoids to compounds in frass offers a more specific and potentially useful mechanism for development of a detection system for T. leucotreta infested fruit. Chemical analysis of T. leucotreta frass and conditioning A. bishopi parasitoids to respond behaviourally to compounds in frass is proposed.
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Gasparoto, Maria Cândida de Godoy. "Epidemiologia comparativa entre \'Candidatus Liberibacter asiaticus\' e \'Candidatus Liberibacter americanus\' em ambiente controlado." Universidade de São Paulo, 2010. http://www.teses.usp.br/teses/disponiveis/11/11135/tde-20102010-164555/.
Full textAbstract:
Huanglongbing é a mais destrutiva doença da citricultura mundial. Seu recente relato no Brasil, em 2004, e a detecção de duas espécies bacterianas associadas à doença -Candidatus Liberibacter asiaticus e Candidatus Liberibacter americanus resultaram em poucos estudos do comportamento do Huanglongbing nas condições dos pomares brasileiros. Os objetivos deste trabalho foram (i) comparar a eficiência de infecção por Candidatus Liberibacter asiaticus e Candidatus Liberibacter americanus em plantas cítricas inoculadas por meio de enxertia com as duas espécies bacterianas, separadamente, e mantidas sob diferentes temperaturas, e (ii) comparar o progresso temporal e espacial do Huanglongbing causado por ambas as espécies, a partir da infecção natural por Diaphorina citri, tendo plantas de citros ou Murraya paniculata (murta) como fonte primária de inóculo. Para alcançar o primeiro objetivo, dois experimentos foram conduzidos em câmaras de crescimento com temperatura e fotofase controladas. A incidência da doença foi determinada por Real-Time PCR de amostras foliares. As temperaturas mais amenas foram favoráveis à infecção por Candidatus Liberibacter americanus, enquanto que altas temperaturas não afetaram a infecção de Candidatus Liberibacter asiaticus. A eficiência de infecção para esta última espécie foi favorecida nas temperaturas de 17/22°C e 22/27°C (noturna/diurna, respectivamente). Para cumprir com o segundo objetivo, um experimento foi conduzido com diferentes fontes de inóculo, que corresponderam aos seguintes tratamentos: (i) plantas de laranjeira doce da variedade Natal infectadas por Candidatus Liberibacter asiaticus ou Candidatus Liberibacter americanus, (ii) unicamente plantas de Murraya paniculata infectadas por Candidatus Liberibacter americanus e (iii) unicamente plantas de laranjeira doce da variedade Natal infectadas por Candidatus Liberibacter americanus. Cada tratamento foi aplicado em um compartimento isolado de uma casade- vegetação. O primeiro tratamento foi repetido. Em todos os compartimentos, 156 a 158 plantas de laranjeira doce da variedade Valência foram dispostas ao redor das plantas fonte de inóculo. Psilídeos livres das bactérias foram periodicamente confinados em plantas fonte de inóculo e, posteriormente foram liberados na casa-de-vegetação para livre movimentação e multiplicação. Quando as duas espécies bacterianas estavam presentes nas diferentes plantas cítricas utilizadas como fonte de inóculo, houve maior detecção de Candidatus Liberibacter asiaticus e maior eficiência de aquisição desta espécie bacteriana por psilídeos. Quando somente Candidatus Liberibacter americanus estava presente nas plantas fonte de inóculo, a eficiência de transmissão foi maior quando Murraya paniculata foi utilizada como fonte de inóculo, mostrando que Diaphorina citri pode adquirir naturalmente Candidatus Liberibacter 12 americanus de Murraya paniculata e transmiti-la para plantas cítricas. A eficiência de aquisição da espécie Candidatus Liberibacter americanus também foi maior tendo Murraya paniculata como planta fonte de inóculo e não citros.Huanglongbing is the most destructive disease of citrus worldwide. There are few studies on the behavior of Huanglongbing in the Brazilian orchards conditions due to the recent report in Brazil, in 2004. Two bacterial species were associated with the disease in Brazil: Candidatus Liberibacter asiaticus and Candidatus Liberibacter americanus. The aims of this work were (i) to compare the efficiency of infection by Candidatus Liberibacter asiaticus and Candidatus Liberibacter americanus in citrus graft-inoculated plants with both bacterial species, separately, and kept under different temperatures, and (ii) to compare the spatio-temporal progress of Huanglongbing caused by both species, naturally transmitted by Diaphorina citri, having infected citrus plants or Murraya paniculata (jasmine orange) as primary inoculum sources. To achieve the first objective, two experiments were carried out in plant growth chambers with controlled temperature and light. Disease incidence in the inoculated plants was determined by Real-Time PCR of the leaf samples. The milder temperatures were favorable to Candidatus Liberibacter americanus infection, while the higher temperatures did not affect the infection by Candidatus Liberibacter asiaticus. The infection by this latter species was favored by temperatures of 17/22ºC and 22/27°C (night/day, respectively). To achieve the second objective, an experiment was carried out with different sources of inoculum, corresponding to the following treatments: (i) Natal sweet orange plants infected by Candidatus Liberibacter asiaticus or Candidatus Liberibacter americanus, (ii) only Murraya paniculata plants infected by Candidatus Liberibacter americanus and (iii) only Natal sweet orange plants infected by Candidatus Liberibacter americanus. Each treatment was applied in an isolated compartment of a screenhouse. The first treatment was repeated. In all of the compartments, from 156 to 158 Valencia sweet orange plants were located around the source of inoculum plants. Psyllids free of the bacteria were periodically confined in source of inoculum plants and, after this period, they were set free, and allowed to the free movement and multiplication inside the screenhouse. When both bacterial species were present in the different citrus plants as source of inoculum, there was higher detection of Candidatus Liberibacter asiaticus than Candidatus Liberibacter americanus and higher acquisition efficiency of the former bacterial species than the later by psyllids. When only Candidatus Liberibacter americanus was present in the source of inoculum plants, the higher transmission efficiency was reached when Murraya paniculata served as source of inoculum, showing that Diaphorina citri can naturally acquire Candidatus Liberibacter americanus from Murraya paniculata and transmit it to citrus plants. The acquisition efficiency of the 14 Candidatus Liberibacter americanus species was higher with Murraya paniculata as source of inoculum than with citrus plants was the source of inoculum.
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Mandzukic, Adis. "Unga vuxna i demokratin : En fallstudie om hur politiska handlingar ser ut hos inrikes- och utrikesfödda medborgare." Thesis, Linnéuniversitetet, Institutionen för statsvetenskap (ST), 2018. http://urn.kb.se/resolve?urn=urn:nbn:se:lnu:diva-70040.
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Elective participation varies considerably among domestic and foreign born young adults. In 2014, there was a difference of 16,1 percentage among domestic and foreign born men in electoral participation and between women there was a difference of 19,3 percentage. In democracies, political equality is important where all citizens have the same political right. The purpose is to answear how political acts are seen among young adults (18-25 years old) domestic and foreign born and if there are similarities and differences and if the political acts are based on their living conditions. This is a qualitative study because I want to get the respondents’ responses at the individual level through interviews. The study showed no difference among domestic or foreign born to political acts based on their living conditions. The reason for that may be the respondents who were foreign born came to Sweden as children and had taken part in society in the same way as a native born.
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Rydberg, Linn. ""En dålig dag kan jag inte göra annat än att gråta" : Utsatta EU-medborgares strategier för att hantera våld, hot och kränkande behandling." Thesis, Umeå universitet, Institutionen för socialt arbete, 2020. http://urn.kb.se/resolve?urn=urn:nbn:se:umu:diva-181452.
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Flera studier har uppmärksammat att utsatt EU-medborgare i Sverige många gånger blir offer för hot, trakasserier och våldsbrott till följd av deras sårbara livssituation och nedsatta tillgång till skydd i landet. Denna studie syftar till att undersöka hur utsatta EU- medborgare upplever och hanterar risker för våld, hot och kränkande behandling. Datan består av kvalitativa semistrukturerade intervjuer med sju utsatta EU-medborgare i Umeå kommun. I studien har två teorier använts för att analysera materialet vilka är stigma samt aktiva och passiva copingstrategier. Dessa har använts för att ge en djupare analys av hur copingstrategier sammanhänger med upplevelser av stigmatisering. Resultatet visar att de utsatta EU-medborgarna upplever att de till följd av deras ursprung från Rumänien förknippas med negativa egenskaper och riskerar att bli föremål för diskriminering och kränkande behandling. Det framkommer att gruppen på olika sätt måste förhålla sig till sitt stigma vilket begränsar deras handlingsutrymme och vilka strategier de har tillgång till för att hantera erfarenheter och oro av att utsättas för kränkande behandling. Resultatet visar att hur väl man har lyckats frigöra sig från den egna gruppen får tillgång till fler aktiva strategier. En slutsats från studien är att strategierna gruppen använder bör förstås utifrån dimensionen stigmatisering och förslagsvis benämnas som anpassade strategier, det vill säga där man agerar i en kontext av underordning och på olika sätt förhåller sig till stigmat.Several studies have noted that vulnerable EU citizens in Sweden often become victims of threats, harassment and violent crimes due to their vulnerable life situation and reduced access to protection. This study aims to examine how vulnerable EU citizens experience and manage risks of violence, threats and abusive treatment. The data consists of qualitative semi- structured interviews with seven vulnerable EU citizens in Umeå municipality. In this study, two theories have been used to analyze the results which are stigma as well as active and passive coping strategies. These have been used to provide a deeper analysis of how coping strategies are associated with experiences of stigmatization. The results show that vulnerable EU citizens feel that they, as a result of their origin from Romania, are associated with negative characteristics and are at risk of discrimination and abusive treatment. It appears that the group must relate in various ways to their stigma, which limits their range of options and the strategies available to them, to deal with experience and fear of being subject to abusive treatment. The results show that people who manage to free themselves from the group get access to more active strategies. A conclusion from the study is that the understanding of strategies used by vulnerable EU citizens should include the dimension of stigmatization and be referred to as adaptive strategies, that is, where one acts in a context of subordination and in different ways must relate to the stigma.
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Junior, Mauro Ferreira Bonfim. "Avaliação da capacidade reprodutiva de populações de Pratylenchus spp. frente a diferentes espécies vegetais." Universidade de São Paulo, 2010. http://www.teses.usp.br/teses/disponiveis/11/11135/tde-25022010-081502/.
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Os nematoides que atualmente tem sido classificados como P. coffeae, demonstram ampla variabilidade morfológica, molecular e quanto à reação à diferentes hospedeiros. Por conseguinte, é essencial que se identifique corretamente as espécies e que se conheça a capacidade de parasitismo em alguns hospedeiros, para que se possa estabelecer medidas de controle e estimar eventuais riscos da entrada de um patógeno em uma área com hospedeiro suscetível. Neste sentido, a presente pesquisa propõe, numa primeira parte, uma medida de controle de P. jaehni (K5), que é muito agressivo à cafeeiro arábico, baseada no uso de plantas má hospedeiras. Na segunda parte deste trabalho é realizada uma caracterização da reação de diferentes espécies vegetais à quatro populações de Pratylenchus spp. Em virtude do exposto, este estudo objetivou avaliar a reação de diferentes cultivares de feijoeiro comum frente à P. jaehni (K5), visando seu possível uso no manejo de áreas cafeeiras infestadas e caracterizar a reação de diferentes espécies vegetais de importância econômica (café, porta-enxertos cítricos, banana e sorgo) frente à quatro populações de Pratylenchus spp. As populações inciais utilizadas nos experimentos variaram entre 180 e 200 nematóides. Em todos os experimentos, os nematóides foram extraídos das raízes pelo método de Coolen e D´Herde (1972) e, eventualmente, do substrato pelo método de Jenkins (1964). Foram realizados três ensaios: i) o primeiro com feijoeiro comum, onde todas as cultivares utilizadas foram resistentes à P. jaehni (K5), inclusive na réplica; ii) o segundo com porta-enxertos cítricos, no qual somente o limão-cravo foi hospedeiro de P. jaehni (K5); iii) o terceiro, no qual foi utilizado café, limão-cravo, banana e sorgo para o conhecimento das respectivas reações frente à 4 populações de Pratylenchus spp. Neste último experimento ocorreu uma reação hospedeira diferenciada para cada população. De acordo com os resultados, concluise que as cultivares de feijoeiro comum utilizadas apresentam potencial de uso em áreas cafeeiras infestadas por P. jaehni (K5), em consórcio ou em áreas de renovação de cafezal, e que as populações de Pratylenchus spp. são capazes de se reproduzir de forma diferenciada frente às espécies vegetais testadas.Nematode populations that have been classified as P. coffeae show wide morphological, molecular and host range variability. Therefore, is essential the correct identification of the species and the knowledge about its parasitism capacity on some hosts, to ensure appropriate control measures and to estimate the entry risks of a pathogen in an area with susceptible host. In this sense, the present research report, firstly, propose a control measure of P. jaehni (K5), which is very aggressive to the arabic coffee, based on the use of poor host plants. In the second part, was carried out a host status evaluation of different plant species to four populations of Pratylenchus spp. In this context, were evaluated the reaction of different common bean cultivars to P. jaehni (K5), for its possible use in management of coffee areas infested with this nematode, and characterized the response of different economic important plant species (coffee, citrus rootstocks, banana and sorghum) to four populations of Pratylenchus spp (IB01P, IB02P, K5 e C1). The initial population used in experiments ranged between 180 and 200 nematodes. In all experiments, nematodes were extracted from roots by Coolen e D\'Herde´s method (1972) and eventually from the substrate by Jenkins´ method (1964). Three assays were conducted and results was as following: i) in the first one, with common bean, all tested cultivars were resistant to P. jaehni (K5), including the replica; ii) in the second one, with rootstocks, only rangpur lime was a good host of P. jaehni (K5); iii) in the third one, in which was used coffee, rangpur lime, banana and grain sorghum, was observed a differential host reaction for each nematode population evaluated. According to the present results, we suggest that common bean cultivars tested have great potential for use, or in intercropping or in crop rotation, in coffee areas infested by P. jaehni (K5) and populations of Pratylenchus spp. have different reproductive fitness in the plants species tested.
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Paschal, Carla. "Exploring Food Security among Elderly Residents in Carrollton and Farmers Branch, Texas." Thesis, University of North Texas, 2018. https://digital.library.unt.edu/ark:/67531/metadc1157515/.
Full textAbstract:
Many senior citizens are surviving on minimal Social Security benefits and as a result, struggle with food security. Metrocrest Services in Farmers Branch, Texas, a suburb of Dallas, is a non-profit organization that provides several food programs to residents of the community including some programs that are specifically tailored to the needs of senior citizens. This project was to provide Metrocrest with an assessment of the food security of their senior clientele as well as other elderly residents of the Metrocrest service area and to evaluate the current senior focused programs. The project utilized qualitative research including both Metrocrest clients and residents who were not Metrocrest clients bot whose demographics were similar. The objectives were to determine the coping skills used by senior citizens in obtaining food, to assess seniors' awareness of the programs offered by Metrocrest, to discover barriers to accessing needed resources and to make recommendations of how programs could be improved or modified if needed. Through my research, I was able to present Metrocrest with a number of recommendations to improve their existing programs. I was also able to recommend some potential new programs that could be designed in conjunction with local senior centers to better serve the community.
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Briganti, Alessandra. "Art garden: host experience." Master's thesis, 2019. http://hdl.handle.net/10400.1/14895.
Full textAbstract:
The Algarve is a Region of south Portugal and Faro is its capital. Every year, thousands of tourists come to Algarve to enjoy its Natural Heritage, visit the amazing beaches and birdwatching spots. Faro also has a rich Historic and Cultural Heritage. To promote them, the city started to host events and festivals of Art, Food, Culture, Music, etc. This led to an increase of the Region Tourism and to the growth of hotels, hostels, guesthouses and other kind of buildings to host guests.
The Art Garden is more than a guesthouse. It is a space of Art, where people can stay and enjoy artworks and temporary art expositions.
The research question of this study is “Can a guesthouse promote the local Culture and Heritage, contribute to making Faro a creative city, and at the same time satisfy the guests needs?”
To answer this question, we designed a space suitable to host guests, that could offer them more than just a common room. Each room of the Art Garden was enriched by a unique mural. The artworks inside the rooms where realized by different artists from different countries and all of them represent attractions from the Natural and Cultural Heritage of the Algarve Region (animals, plants, colors, traditional elements, etc.).
Artists from all over the World came to Faro to paint, visited the Region, created dynamism and enriched the Art offer of the town with their artworks.
The space is officially opened since the end of June, 2019. All the guests already hosted, expressed their enthusiasm to stay in such an artistic and original space.
We consider this project and its realization as a contribute to making Faro a creative city, destination for Culture and Art Tourism, besides the Seasonal Tourism.O Algarve é uma região a sul de Portugal e Faro, a sua capital. Anualmente, milhares de turistas vêm ao Algarve para poder visitar a região e o seu património natural. Visitam praias e exercem a actividade de birdwatching. Faro também tem um interessante património histórico e cultural e com o objetivo de promovê-los a cidade começou a organizar eventos e festivais de Arte, Gastronomia, Cultura, Música, etc. Esta situação deu origem a um crescimento do turismo na região e a construção de hotéis, hostels, guesthouse e outros tipos de infraestruturas para hospedar os turistas. O Art Garden é mais que uma simples guesthouse, é um espaço de arte, onde as pessoas podem apreciar os murais pintados no seu interior e também as exposições temporárias de arte. A questão de investigação é “Pode uma guesthouse promover a cultura e o património local, e ajudar Faro no seu objetivo de tornar-se uma cidade criativa e ao mesmo tempo satisfazer as necessidades dos hóspedes?”. Para responder a esta pergunta, desenhámos um espaço adequado para acolher hóspedes e onde se pode oferecer algo mais que um simples quarto. Cada quarto no Art Garden foi enriquecido com um mural exclusivo e os temas dos murais são diferentes uns dos outros. As obras pintadas nos quartos foram realizadas por artistas provenientes de países diferentes, mas todas elas representam atracções do Património Cultural e Natural da Região do Algarve (animais, plantas, cores, elementos tradicionais, etc.). Os artistas provenientes de várias partes do mundo que chegaram a Faro para pintar o Art Garden e foram eles também turistas da Região; visitaram o Algarve, criaram dinamismo e enriqueceram a oferta artística do país com as suas obras. O espaço foi aberto ao público no fim do mês de Junho de 2019. Todos os hóspedes do Art Garden, manifestaram o seu entusiasmo em permanecer neste espaço tão artístico e original Nós consideramos este projeto e a sua realização como um contributo para tornar Faro uma cidade criativa como destino de um Turismo Cultural e Artístico, contribuindo desta forma para esbater a sazonalidade.
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Linley, Michael. "‘How sports events shape host cities’- Development of a comparative framework for assessing the impact of sporting events on the host location." Thesis, 2021. https://vuir.vu.edu.au/43938/.
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As the costs associated with bidding and hosting mega-events continues to escalate, the need to establish the benefits of these undertakings rises in step with governments coming under increasing scrutiny over the investment in sports events. Despite the billions spent each year in bidding for and hosting major sports events; the assessment of claimed benefits lacks a recognised or comparable method for assessing the hosting of major sporting events, with each federation, organiser or agency applying its own methodology.
Despite an increasing body of research on event outcomes and potential classification frameworks, the mega-event dominant research focus neglects other events and their potential impacts; hampering current and prospective hosts from critically reassessing their event portfolio, bidding more selectively, and grounding events within their longer-term development plans and financial resources.
This research challenges how terminology for the associated and myriad of outcomes the hosting of events has morphed to one of ‘legacy’ without any agreed definition of either the term itself or its constituent components. It seeks to explore whether a conceptual framework for the comparative assessment of event impact across events of different scales and types, including recurrent editions of events for the same host, could be established.
Adopting a focus on event impacts rather than legacies represents not a semantic choice but a determination to create a more constrained framework that allows smaller, higher-frequency events to be considered alongside quadrennial large-scale events on a comparable and consistent basis.
The development of the conceptual framework was grounded in an initial literature review of event impact and legacy assessment from which six core areas (Pillars) of event impact were identified; Economic, Social, Sport, Media, Brand, and Environment with 30 sub-areas (Drivers). From 350+ potential measures identified, 200+ metrics were included in the study with panellists rating measures on both their importance and reliability in assessing event impact. Using a Delphi method, the study sought to establish if consensus views on the relative importance of each of the pillars, drivers, and measures could be established across three survey rounds.
Despite the rhetoric that event legacy is unable to be defined, the findings show that there exists a solid underlying consensus on event impacts and how different areas contribute to the overall impact. Three tiers of impact emerged with Economic and Sport outcomes forming the top tier, with Media, Social and Brand outcomes grouped in a second tier, and the final pillar of Environment forming the lowest tier.
Evidence of significant bias within groups was found that reflects a lack of cross-discipline awareness and the need for greater collaboration between the event sector and academia. Uncovering bias enabled their influence on the consensus scores to be explicitly addressed and placed the importance of each dimension in the context of overall event impact.
The framework established in this study was shown to provide a strong basis for a consensus on the attribution of event impact. Using a multi-level structure allows for the core areas of impact to be consistently assessed in a standardised framework allowing for greater comparability across events, and for hosts to be more informed in building an event portfolio.
Further work on the technical development of the framework and its application by host cities is discussed.
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Fernandes, Rúben Baptista. "Radio Coverage Data Visualization in Neutral Hosting Platform." Master's thesis, 2019. http://hdl.handle.net/10316/87840.
Full textAbstract:
Dissertação de Mestrado em Design e Multimédia apresentada à Faculdade de Ciências e TecnologiaThis dissertation is part of a project by the business Ubiwhere, a Smart Cities product called Smart Lamppost. In summary, this dissertation, was intended to develop a radio coverage visualization for the Smart Lamppost platform, assisting the Neutral Hosting part of the solution. This product consists of the reuse of urban furniture to perform functions in Smart Cities, incorporating in it different functionalities and various hardware elements, such as a station for charging electric cars and the rental capacity of distributed resources for a 5G network communication (Neutral-Host). Neutral Host is defined as a concept that allows several customers to share, through the virtualization of network space, the same antenna to spread the Internet that they intend to distribute. Responding these requirements, is the idea of a platform that will allow stakeholders to book and rent these resources.This project essentially serves to implement on the platform the visualization of the radio coverage and the various ways to manage all the inherent functionalities of Neutral Hosting, giving everyone the opportunity to view in real time all these features of Smart Lamppost. Finally, it is intended to explore web implementation techniques and integrations turning it in a real product for real customers.
A presente dissertação, insere-se num projeto da empresa Ubiwhere, um produto para Smart Cities, denominado Smart Lamppost. Em suma, com esta dissertação, pretendeu-se desenvolver uma visualização de cobertura rádio para a plataforma do Smart Lamppost, com foco na parte de Neutral Hosting da solução. Este produto consiste no reaproveitamento de mobiliário urbano para desempenhar funções nestas Smart Cities, incorporando nele as diferentes funcionalidades e os diversos elementos de hardware, como estação para carregamento de carros elétricos, e a capacidade de aluguer de recursos distribuídos para comunicação de rede 5G (Neutral-Host). Neutral Host surge como um conceito que permite a vários clientes partilharem, através da virtualização de espaço de rede, a mesma antena para difundirem a internet que pretendem distribuir. Para tal, foi criada uma plataforma onde diferentes partes interessadas podem reservar e alugar estes recursos. Este projeto tem como objetivo a implementação, na plataforma, a visualização da cobertura rádio e as diversas formas de gerir todas as funcionalidades inerentes ao Neutral Hosting, dando a possibilidade a todos de visualizar, em tempo real, todos estes recursos do Smart Lamppost. Nesse sentido, este projeto explora técnicas de implementação web e integração na plataforma já existente, num produto real para clientes reais.
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Louw, Johannes Petrus. "The pathogenicity and host specificity of Penicillium spp. on pome and citrus fruit." Diss., 2014. http://hdl.handle.net/2263/43149.
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Penicillium includes some of the most concerning postharvest pathogens of pome and citrus fruit. The pathogenicity and aggressiveness of selected Penicillium spp. previously isolated from South African and European Union fruit export chains were investigated on pome and citrus fruit. New insight and findings were documented in this study. Penicillium digitatum, the most aggressive pathogen on citrus, was also identified the most aggressive on „Beurre Bosc‟, „Beurre Hardy‟ and „Sempre Rosemarie‟ pears. It was also the third most aggressive species on „Granny Smith‟ and „Cripps Pink‟ apples. To our knowledge this is the first report where P. digitatum has been described as an aggressive pathogen on certain pome fruit cultivars. The most concerning species in terms of decay on the evaluated apple cultivars („Royal Gala‟, „Granny Smith‟, „Golden Delicious‟, „Topred‟ and „Cripps Pink‟) and two pear cultivars („Packham‟s Triumph‟ and „Forelle‟) were P. expansum and P. crustosum respectively. New reports concerning spoilage caused by these species were noted on citrus. Penicillium expansum decay and tissue-response lesions were noted on „Nules Clementine‟, „Owari Satsuma‟, „Delta Valencia‟, „Midknight Valencia‟ and „Eureka‟ seeded. Penicillium crustosum caused decay and tissue-response lesions on „Nules Clementine‟, „Nova‟, „Owari Satsuma‟, „Delta Valencia‟, „Cambria Navel‟, „Eureka‟ seeded and „Star Ruby‟. In contrast to more aggressive infections and large surface lesions, some tissue-response lesions sporulated despite their small size, thus allowing the species to complete their life cycle. The second most aggressive species affecting citrus was P. italicum. Pathogenicity of P. solitum was also confirmed on some apple and pear cultivars, although a broader cultivar range and higher level of aggression was observed on pears. Penicillium brevicompactum was only found to be pathogenic on pears. New information regarding host-Penicillium interactions, the potential of cross-infection and the impact each species may have on fruit moving through the market chain was added. Future studies should examine the link between host susceptibility as influenced by maturity and the pathogenic potential of non-host pathogens. Further research is needed to elaborate on the pathogenicity of P. digitatum on pome fruit. Information on market-end losses, the causal agents involved, and inoculum levels and sources may prove beneficial in solving industry problems at the retail-end.Dissertation (MScAgric)--University of Pretoria, 2014.
lk2014
Microbiology and Plant Pathology
MScAgric
Unrestricted
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Nejad, Sara Khakbaz. "Dancing to the Desert: A Proposal for Self-Help Reconstruction of Post-Earthquake Cities in Hot-Arid Climates." Thesis, 2011. http://hdl.handle.net/10012/6504.
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Natural hazards kill 82,500 people globally in a typical year, with earthquakes as the largest cause of death amongst all natural hazards in Central and Southern America, East Asia, Europe, and the Near East. Damages are highest in middle-income countries due to lack of resources for hazard prevention and mitigation. Dancing to the Desert concentrates on Bam, Iran, as a typical post earthquake city, searching for architecture appropriate for post-disaster cities of hot-arid climates. Dancing to the Desert is a discourse on current seismic, urban, and architectural design conditions in hot-arid climates of the globe, and searches for an appropriate architecture for post-disaster cities in developing regions of the desert climate.
Chapter One includes analysis on global seismic hazard conditions, focusing on the hot-arid climates in the world and concentrating on the city of Bam, Iran.
Chapter Two includes a detailed analysis of the traditional as well as contemporary architecture of Bam, searching for appropriate architectural elements to use in the proposed architecture.
Chapter Three proposes a Pilot Project for an orphanage in Bam, based on the architectural elements and strategies discussed in Chapter Two. Through scientific research, case studies, a site visit to Bam, and discussions with local residents, this thesis finds an appropriate proposal adaptable to all post-disaster cities of the hot-arid climate. It also suggests various strategies for disaster prevention and mitigation through public education. These strategies educate the public in employing cultural and environmental friendly resilient architecture, which will subsequently reduce damage and fatalities on brisk of disaster. It also familiarizes the public with the proposed disaster prevention and mitigation strategies and facilitates the adoption of the proposed design in future post-disaster conditions.
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Hsu, Tseng-Chien, and 許增謙. "Research on Essential Oil Comstituents ofLeaves of Citrus sunki Hort. Ex Tanaka." Thesis, 2006. http://ndltd.ncl.edu.tw/handle/62559065265353410636.
Full textAbstract:
碩士中原大學
化學研究所
94
Abstract Citrus sunki Hort. Ex Tanaka, name Sunki, is one type of Rutaceae. In this research, leaves of sunki were collected, washed, dried and fragmented. The neutral essential oil was obtained through indirect steam distillation, and the steps of solvent extraction, base treatment, dehydration and condensation. The average oil extraction rate of sunki leaves is 0.6%. The neutral essential oil was isolated and purified by chromatography, dividing into hydrocarbon and hydroxy compounds, with the former taking 51% of the content and the latter 49%. Twenty-eight compounds were identified through comparison among the spectra of GC, GC/MS, IR and NMR. The hydrocarbon compounds include α-Pinene, β-Pinene, D-Limonene, Z-Ocimene, p–Cymene, γ-Terpinene, Terpiolene, β-Elemene, Caryophyllene, Cadinene, α-Bergamotene, α-Caryophyllene, (Z,E)-α-Farnesene, α-Farnesene, Copaene, α-Selinene, Eremophilene1 17 compounds. Hydroxy compounds contain Linalool oxide, β-Linalool, α-Cadinol, p-Cymen-8-ol, Methyl thymyl ether, trans-Nerolidol, Spathulenol, Caryophyllene oxide, Hexahydrofarnesyl acetone, Isophytol and Phytol 11 compounds.
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Tien, Hsing-Ju, and 田幸茹. "Quantitative and Qualification Detection of Candidatus Liberibacter asiaticus in Citrus Hosts and the Asian Citrus Psyllid (Diaphorina citri Kuwayama)." Thesis, 2009. http://ndltd.ncl.edu.tw/handle/33372384967660479651.
Full textAbstract:
碩士國立臺灣大學
植物病理與微生物學研究所
97
Citrus huanglongbing (HLB), also called citrus greening, is a destructive disease of citrus, which has been found in Asia, African and America. The disease is caused by a phloem-limited bacterium, tentatively named Candidatus Liberibacter sp., which can not be cultured in vitro so far. The pathogen can be transmitted by psyllids and bud-wood grafting. In Taiwan, the pathogen was categorized into Candidadus Liberibacter asiaticus (Las) and its vector is the Asia citrus psyllid, Diaphorina citri Kuwayama (Homoptera: Psyllidae). Las inhabits its host plants with low concentration and uneven distribution, the detection of Las used to be not easy. The PCR-based assay was considered to be a more reliable and adoptable method for Las detection, but it can not be applied in quantitative monitoring of Las. This thesis was dedicated to apply the real-time PCR technique for the quantitative detection of Las. This newly devised method could be also used to monitor the multiplicative fluctuation of Las in the graft-inoculation and psyllid-transmission tests and to study the relationship between psyllids and Las. In the graft-inoculation tests, the result demonstrated that the multiplicative fluctuation of Las was different among four citrus hosts such as Ponkan mandarins (PM), Liu-Cheng sweet oranges (LC), Wentan pomeloes (WP) and Eureka lemons (EL). Based on the developed real-time PCR assays, Las could be detected in PM 3 weeks post-inoculation (wpi) whereas in LC 5 wpi. The multiplicative rate of Las was significantly increased in LC 8 wpi whereas in PM 12 wpi. However, the concentration of Las in PM was higher than that in LC 16 wpi. Both PM and LC started to show yellowing symptoms on leaves 4 months after graft-inoculation. Las could be detected in EL and WP 7~8 wpi, and their concentration of Las kept low level even 24 wpi. The quantitative difference was also showed in the detection of various citrus cultivars infected by Las with the real-time PCR assay, and the results indicated the comparative concentration was Mucot＞PM＞LC＞Calamondin＞WP. Las could be detected in both PM and LC 3 wpi in the psyllid-transmission tests, but the amount of Las did not significantly increase even 14 wpi. Obviously, the graft-inoculation had a better efficiency for replication of Las than the psyllid-transmission. In the acquisition tests, the data revealed that the extension of acquisition-access time did not elevate the Las-carrying percentages (keeping a range at 40~60%) for psyllid populations. The amounts of Las were approximately hundreds to thousands of copies in individual infected adult in this acquisition test, which were less than those collected from the field. This result hints that acquisition of Las is not easy for adult psyllids, and most adults with high concentration of Las should originate from Las-carrying nymphs. The nymph tests also showed that the quantity of Las was abundant after 4-instar, and adults carried more Las than nymphs, which suggests that the nymphal stages are importantly multiplicative periods for Las in psyllids. Our results demonstrated that the transmission efficiency of Las with graft-inoculation was better than that with psyllid-inoculation. Thus, establishment of Las-free nursery foundation should be considered to be the most important measure for the control of HLB. For avoidance of vector-transmission, elimination of diseased plants and decrease of psyllid vectors in the field should be seriously conducted to prevent the production of Las-carrying psyllids and retard the spreading of HLB.