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Bianchini, Luciana. "Identificação molecular de isolados do fitoplasma do enfezamento vermelho do milho coletados no Estado de São Paulo." Universidade de São Paulo, 2002. http://www.teses.usp.br/teses/disponiveis/11/11135/tde-07082002-142005/.
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A partir de meados da década de 80, com a expansão da cultura do milho para além das épocas tradicionais de cultivo, quer pela prática da safrinha ou por plantios irrigados, vem ocorrendo um aumento na incidência de doenças a secundária. Dentro deste contexto, o enfezamento vermelho do milho, relatado no país primeiramente em 1970, vem ocorrendo de forma freqüente, apresentando altos índices de ocorrência, muitas vezes com comprometimento total da produção. As plantas infectadas apresentam uma sintomatologia complexa facilmente confundida com viroses. O sintoma mais característico é o avermelhamento foliar. Além do avermelhamento as plantas apresentam redução na altura, perfilhamento basal e axilar, espigas extranumerárias e colmos afinados. Essa doença é causada por um procarioto não cultivável em meio de cultura, habitante exclusivo do floema, denominado fitoplasma, veiculado de forma persistente e propagativa pela cigarrinha Dalbulus maidis. Devido às características do patógeno, a única forma de controle promissora é a utilização de variedades tolerantes/resistentes. Para eficiência na obtenção destas variedades é necessário um diagnóstico correto e conhecimento sobre a variabilidade metodologia mais eficiente tanto para diagnose correta como para investigar essa variabilidade tem sido o PCR. O PCR, utilizando oligonucleotídeos baseados no gene 16SrDNA seguido da análise de RFLP, proporciona uma identificação mente a classificação de fitoplasmas é fundamentada no perfil molecular obtido por análise de RFLP de fragmentos do gene 16SrDNA amplificados. Com base nestas considerações, o trabalho teve como objetivo caracterizar molecularmente isolados do fitoplasma associado ao enfezamento vermelho do milho, coletados em quatro regiões produtoras de milho do estado de São Paulo. A sintomatologia para cada amostra de milho foi anotada. Foram usados dois pares de oligonucleotídeos universais para fitoplasmas em duplo PCR, um par de oligonucleotídeo especificamente desenvolvido para detecção do fitoplasma do enfezamento vermelho do milho, além de oligonucleotídeos para detecção de fitoplasmas pertencentes a grupos específicos. Após amplificação e eletroforese, 29 isolados foram selecionados para a identificação através de RFLP. Fragmentos de DNA foram submetidos à digestão com diferentes enzimas de restrição com o objetivo de identificar/classificar o fitoplasma. Os padrões de bandas obtidos após a eletroforese em gel de poliacrilamida foram comparados com os padrões atuais para classificação dos fitoplasmas. Todos os isolados analisados apresentaram idênticos padrões de bandas, para cada enzima de restrição, considerada individualmente. Não houve diferenciação de acordo com a região geográfica de coleta ou de acordo com intensidade de sintomas apresentados. Todos os isolados foram identificados como pertencentes ao grupo I e subgrupo B da classificação molecular atualmente adotada para estes microorganismos.Since the middle 80s, an increase in year round cropping of maize resulted in a spread of secondary diseases in the crops major production areas. In this context, maize busy stunt, firstly appointed in Brazil in 1970, is occurring more frequently, often with total damage of production. Infected plants show a complex symptomatology, easily confounded with virus-caused diseases. The most characteristic symptom is leaf reddening. Besides the reddening diseased plants show stunting, often developing tillering. This disease is caused by a phytoplasma, a wall- less prokaryote, uncultivable, phloem inhabitant. This pathogen is transmitted by the leafhopper Dalbulus maidis, a in persistent and propagative manner. Due to the pathogens characteristics, the best control measure is the use of tolerant/resistant plants. For efficiency in breeding, accurate procedures of detection and an investigation of the pathogens genetic variability are necessary. The more accurate manner is using PCR. PCR, using 16SrDNA based primers pairs and followed by RFLP analysis, offers a safe identification of the pathogen. Today the phytoplasma classification is based in molecular patterns obtained by RFLP analysis of amplified 16SrDNA gene fragments. This works objective was the molecular characterization of maize bushy stunt phytoplasma strains collected in four corn production areas in São Paulo state, Brazil. The simptomatology to every maize sample was saved. Two primer pairs in nested PCR and a specific primer pair developed to MBS detection were used, besides group specific phytoplasma primers pairs. After amplification and electrophoresis, 29 samples were selected. These selected samples were digested with different restriction enzymes to identify/classify the phytoplasma. The fragments sizes obtained by electrophoresis through 4,5% polyacrilamide gel were compared with the references classification patterns. All analyzed samples showed identical fragment-size patterns, for each restriction enzyme considered individually. There was no difference between these samples according to geographic collect region or according to symptoms. All strains were identified as belonging to group I and subgroup B of molecular classification.
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Punyapornwithaya, Veerasak. "Molecular epidemiology of mycoplasma mastitis outbreak." Pullman, Wash. : Washington State University, 2010. http://www.dissertations.wsu.edu/Dissertations/Spring2010/v_punyapornwithaya_042110.pdf.
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Cook, Beth Susannah. "Development of genetic tools for functional genomic analysis of Mycoplasma hyopneumoniae." Thesis, Royal Veterinary College (University of London), 2013. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.618285.
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Manhart, Lisa Elaine. "Epidemiology of Mycoplasma genitalium in women /." Thesis, Connect to this title online; UW restricted, 2002. http://hdl.handle.net/1773/10876.
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Robinson, Sally Rae. "Isolation, characterisation and molecular typing of feline mycoplasma species." Connect to thesis, 2009. http://repository.unimelb.edu.au/10187/5512.
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The exact role of mycoplasma in feline ocular and respiratory disease is not yet understood. The results of previous studies are contradictory in this regard. There is some evidence to suggest that M. felis has a pathogenic role in such diseases, but it is inconclusive.The aim of this study was to investigate the prevalence and anatomical distribution of mycoplasmas in a population of shelter cats, to determine which species were present, and establish the association of their presence with ocular or respiratory disease.
The prevalence of mycoplasma in the 110 cats examined was 71.8%, as determined by in vitro culture. Mycoplasma was most commonly isolated from the pharynx, followed by the bronchus and conjunctiva. In infected cats, mycoplasmas were likely to be isolated from multiple anatomical sites.
The polymerase chain reaction (PCR) was used to amplify part of the 16S rRNA gene, and the mutation scanning technique non-isotopic single-strand conformation polymorphism (SSCP) was utilised to delineate mycoplasma isolates based on nucleotide sequence variation. PCR-SSCP proved to be a useful method to screen large numbers of samples for variation and to group them according to species.
The species of mycoplasma identified by nucleotide sequencing were M. felis and M. gateae. It was not determined whether it was possible to differentiate between M. gateae and M. arginini based on SSCP profile results with the target DNA region used due to their almost identical nucleotide sequence. This group of M. gateae/M. arginini served as a useful non-pathogenic comparison group to M. felis.
There was no statistically significant difference between M. felis and the M. gateae/M. arginini group with respect to prevalence or anatomic distribution. There was no evidence of any association of mycoplasma with disease linked to any of the anatomic locations studied.
Mycoplasmas were isolated from the lower respiratory tract in 42.7% of cats. The isolation of mycoplasmas from the lower respiratory tract of healthy cats has been reported once, but this is the first report of M. felis being isolated from this location in healthy cats. This finding indicates that the isolation of mycoplasmas from the lower respiratory tract is not sufficient evidence to implicate a role in respiratory disease.
Mycoplasmas were not significantly involved in ocular or respiratory disease in the population of cats studied. More likely, they are commensal organisms in the conjunctiva, pharynx and bronchus. Whether they are capable of playing an opportunistic role in disease, or what conditions may facilitate such a role remains to be determined.
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Brewster, Veronica Rose. "Towards an eradication strategy for mycoplasma hypneumoniae from the UK pig herd." Thesis, Royal Veterinary College (University of London), 2016. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.701680.
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Roberts, S. J. "Bacterial diseases of woody ornamental plants." Thesis, University of Leeds, 1985. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.375533.
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Olsen, Mary W. "Diseases of Urban Plants in Arizona." College of Agriculture and Life Sciences, University of Arizona (Tucson, AZ), 1999. http://hdl.handle.net/10150/144807.
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26 pp.Geographically, Arizona can be divided roughly into four areas, southwest, central, southeast, and northern. These regions correspond with four climatic zones, allowing a large and diverse number of plants to be grown for landscaping purposes. But, interestingly, in this desert environment many of the parasitic diseases in landscape plants are caused by a limited number of plant pathogens. This publication discusses some of those diseases that are sufficiently important to the urban plants in all areas Arizona.
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Taylor, Kathryn, and Danielle Ellis. "Mycoplasma-like Organisms as the Causal Agent for Macrophylla Decline." College of Agriculture, University of Arizona (Tucson, AZ), 1996. http://hdl.handle.net/10150/220516.
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Previous literature concerning citrus and other tree crops led us to ask if there was molecular evidence for mycoplasma -like organisms (MLOs) as the causal agent of Macrophylla decline and two other decline diseases, citrus blight and lemon sieve tube necrosis. We had molecular probes available to us that were either specific for MLOs of tree diseases and others that were universal for all known types of MLOs. We used a polymerase chain reaction (MLO) to determine if MLOs were present in the vascular tissues of decline and healthy citrus. I all trials performed, the trees were negative for MLO-PCR products. In addition, we attempted to transmit putative MLO 's from decline affected trees to Vinca rosea MLO-nurse plants. We were unable to affect this type of transfer. In addition, our attempts to identify MLO's in phloem tissue gave us negative results. We have since revised our hypothesis. We are currently pursuing the hypothesis that these decline disorders are the result of a rootstock scion incompatibility, that we may be able to avoid culturally, while maintaining these valuable combinations.
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Persson, Anja M. "Molecular characterisation of Mycoplasma mycoides subsp. mycoides SC /." Uppsala : Dept. of Veterinary Microbiology, Swedish Univ. of Agricultural Sciences ([Institutionen för veterinärmedicinsk mikrobiologi], Sveriges lantbruksuniv.), 2002. http://epsilon.slu.se/avh/2002/91-576-6364-5.pdf.
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Van, der Merwe Elizabeth Frances. "Preliminary investigations into ostrich mycoplasmas : identification of vaccine candidate genes and immunity elicited by poultry mycoplasma vaccines." Thesis, Stellenbosch : Stellenbosch University, 2006. http://hdl.handle.net/10019.1/17411.
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Thesis (MSc)--University of Stellenbosch, 2006.ENGLISH ABSTRACT: Ostrich farming is of significant economical importance in South Africa. Three ostrich mycoplasmas, Ms01, Ms02 and Ms03 have been identified previously, and were provisionally named ‘Mycoplasma struthiolus’ (Ms) after their host Struthio camelus. Ostrich mycoplasmas are the major causative organisms of respiratory diseases, and they cause stock losses, reduced production and hatchability, and downgrading of carcasses and therefore lead to large economic losses to the industry. In order to be pathogenic to their host, they need to attach through an attachment organelle, the so-called tip structure. This structure has been identified in the poultry mycoplasma, M. gallisepticum, and is made up of the adhesin GapA and adhesin-related CrmA. Currently, no ostrich mycoplasma vaccine is commercially available and for this reason the need to develop one has arisen. Therefore the first part of this study was dedicated to the identification and isolation of vaccine candidate genes in the three ostrich mycoplasmas. Four primer approaches for polymerase chain reactions (PCR’s), cloning and sequencing, were used for the identification of adhesin or adhesin-related genes from Ms01, Ms02 and Ms03. The primer approaches revealed that the target genes could not be identified due to the high diversity of sequences that were generated. Therefore sequences were also compared with those of other mycoplasma species in BLAST searches. Results showed that the most significant hit was with the human pathogen M. hominis oppD, which is located in the same operon as the membrane protein P100 involved in adhesion. Other hits were with ABC transporters which may also play a role in cytadhesion. The second part of this study was aimed at testing whether two poultry mycoplasma vaccines, M. synoviae and M. gallisepticum, can be used in ostriches to elicit immune responses until an ostrich mycoplasma vaccine has been developed. Ostriches on three farms of different age groups in the Oudsthoorn district were therefore vaccinated with these vaccines in a vaccine trial. The enzymelinked immunosorbent assay (ELISA) was used to test the level of antibody response. Results showed that both vaccines elicited an immune response in all three age groups. A high percentage of the ostriches reacted positively, which indicates that both vaccines elicit antibody responses and may therefore give protection against ostrich mycoplasma infections.
AFRIKAANSE OPSOMMING: Volstruisboerdery is ‘n belangrike ekonomiese sektor in Suid-Afrika. Drie volstruismikoplasmas, Ms01, Ms02 en Ms03, is voorheen geïdentifiseer en voorlopig ‘Mycoplasma struthiolus’ (Ms) benaam na aanleiding van hul gasheer, Struthio camelus. Volstruismikoplasmas is die grootste oorsaaklike organismes van respiratoriese siektes, kudde verliese en die afgradering van karkasse wat lei tot groot ekonomiese verliese in die volstruisbedryf. Ten einde patogenies vir die gasheer te wees, moet mikoplasmas deur middel van ‘n aanhegtingsmeganisme vasheg – die sogenaamde puntvormige struktuur. Hierdie struktuur is in die pluimvee mikoplasma M. gallisepticum geïdentifiseer, en bestaan uit aanhegting proteïen GapA en die aanhegting verwante proteïen CrmA. Tans is geen volstruismikoplasma entstof kommersieel beskikbaar nie, en derhalwe het die behoefte ontstaan om so ‘n entstof te ontwikkel. Die eerste gedeelte van hierdie studie is dus gewy aan die identifisering en isolering van entstof kandidaat gene in al drie volstruismikoplasmas. Vier inleier benaderings vir polimerase ketting reaksies (PKR), klonering asook geenopeenvolging bepalings vir die identifisering van aanhegting of aanhegting verwante gene vanuit Ms01, Ms02 en Ms03 is gebruik. Die inleier benaderings het getoon dat die teikengene nie geïdentifiseer kon word nie as gevolg van hoë variasie in die gegenereerde geenopeenvolgings. Derhalwe is geenopeenvolgings met ander mikoplasma spesies deur middel van BLAST soektogte vergelyk. Resultate het getoon dat die betekenisvolste ooreenstemming dié met die menslike patogeen M. hominis oppD was, wat deel vorm van die membraan proteïen P100 operon wat betrokke is by aanhegting. Ander ooreenstemmings sluit ABC transporters in wat moontlik betrokke kan wees by aanhegting. Die tweede gedeelte van hierdie studie het ten doel gehad om te toets of twee pluimvee mikoplasma entstowwe, M. synoviae en M. gallisepticum, gebruik kan word in volstruise om immuunresponse te ontlok tot tyd en wyl ‘n volstruismikoplasma entstof ontwikkel is. Volstruise vanaf drie plase in verskillende ouderdomsgroepe in die Oudtshoorn distrik was ingeënt met hierdie entstowwe in ‘n entstof proefneming. Die ensiem-afhanklike immuno-absorpsie essaï (ELISA) was gebruik om antiliggaam response te toets. Die resultate het getoon dat beide entstowwe immuunresponse ontlok het in al drie ouderdomsgroepe. ‘n Groot persentasie van die volstruise het positief gereageer wat ‘n aanduiding is dat beide entstowwe immuunresponse ontlok het en kan dus beskerming bied teen volstruismikoplasma infeksies.
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Campos, Guilherme Barreto. "Detecção de Mycoplasma hominis, M. genitalium e M. penetrans no trato urogenital feminino e a sua relação com polimorfismos genéticos e expressão de citocinas em mulheres atendidas no município de Vitória da Conquista - BA." Universidade de São Paulo, 2013. http://www.teses.usp.br/teses/disponiveis/42/42132/tde-19032014-145646/.
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Foram obtidos dados clínico-demográficos, swab vaginal e sangue de 302 mulheres. Detectou-se Mollicutes, Mycoplasma hominis e M. genitalium em 76,2%, 15,9% e 1,7% das amostras respectivamente. Frequência de 31,8% e 28,1% na qPCR foi encontrada para M. genitalium e M. hominis respectivamente. A infecção por micoplasmas foi associada a sinais e sintomas clínicos. A frequência de Trichomonas vaginalis Neisseria gonorrhoeae Gardnerella vaginalis e Chlamydia trachomatis foi de 3,0%, 21,5%, 42,4%, 1,7% respectivamente. Co-infecção destas espécies com micoplasmas foi encontrada. No polimorfismo da IL-1b, houve maior prevalência do genótipo CC, no entanto, o alelo T foi relacionado ao pequeno aumento dos níveis da interleucina no grupo caso. Para o polimorfismo de IL-6, o genótipo GG apresentou maior frequência, e o genótipo GC foi associado ao aumento dos níveis plasmáticos da citocina no grupo caso. O aumento dos níveis de IL-1b foi associado à presença M. hominis e ao fato das mulheres apresentarem sinais ou sintomas de infecção.Clinical and demographic data, samples of vaginal swab and peripheral blood were obtained from 302 women. Mollicutes, Mycoplasma hominis and M. genitalium were detected in 76.2%, 15.9% and 1.7%, respectively. Frequency of 31.8% and 28.1% in qPCR was found for M. genitalium and M. hominis respectively. Infection by genital mycoplasmas, especially when analyzed by qPCR, was significantly associated with clinical signs and symptoms of sexually transmitted infections. The frequency of Trichomonas vaginalis, Gardnerella vaginalis, Neisseria gonorrhoeae and Chlamydia trachomatis was 3.0%, 21.5%, 42.4% and 1.7% respectively. Co-infection among these species and mycoplasmas was founded. In polymorphism of IL-1b, the genotype CC was more prevalent; however, the T allele was related to small increase of the interleukin levels in the group case. In the polymorphism of IL-6, higher frequency was of the genotype GG, and the GC genotype was associated with increased plasma levels of the cytokine in the group case. Increased levels of IL-1b were associated with presence of M. hominis and signs and/or symptoms of infection.
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Whalin, Rebekah Christine. "The Detection of Mycoplasmas in Migratory Birds." Miami University Honors Theses / OhioLINK, 2009. http://rave.ohiolink.edu/etdc/view?acc_num=muhonors1239986702.
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Czifra, György. "Identification of Mycoplasma gallisepticum antigens with diagnostic and protective properties /." Uppsala : Swedish Univ. of Agricultural Sciences (Sveriges lantbruksuniv.), 1999. http://epsilon.slu.se/avh/1999/91-576-5900-1.pdf.
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Strydom, Marliz. "The ostrich mycoplasma Ms02 partial genome assembly, bioinformatic analysis and the development of three DNA vaccines." Thesis, Stellenbosch : Stellenbosch University, 2013. http://hdl.handle.net/10019.1/80381.
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Thesis (MSc)--Stellenbosch University, 2013.ENGLISH ABSTRACT: The South African ostrich industry is under enormous threats due to diseases contracted by the ostriches. H5N2 virus (avian influenza) outbreaks the past two years have resulted in thousands of ostriches having to be culled. However, the more silent respiratory infectious agents of ostriches are the three ostrich-specific mycoplasmas. Named Ms01, Ms02, and Ms03, these three mycoplasmas are responsible for dramatic production losses each year, due to their intrusive nature and the fact that no vaccines are currently available to prevent mycoplasma infections in ostriches. The use of antibiotics does not eradicate the disease completely, but only alleviates symptoms. The ostrich industry commissioned investigations into the development of three specific vaccines using the relatively novel approach of DNA vaccination. The concept of DNA vaccine development is based on the availability of complete genome sequences of the pathogen against which the vaccine is to be developed. This is necessary in order to identify vaccine candidate genes through comparative genomic studies. The Ms02 genome has previously been sequenced, resulting in 28 large contiguous sequences. This thesis used the technique of Thermal Asymmetric Interlaced Polymerase Chain Reaction (TAIL-PCR) to attempt assembly of these 28 contiguous sequences. The number was reduced to 14 large contiguous sequences, which were then subjected to repetitive sequence analysis and open reading frame analysis. Bioinformatic software was also used to predict the origin of replication. The extent of repeats in the Ms02 genome is illustrated, as well as the problems with genome assembly when dealing with repetitive-rich and A+T-rich genomes as those of mycoplasmas. Previous studies determined the mycoplasma oppA gene to be a good vaccine candidate gene, due to its cytadherent properties. This thesis describes the development of three DNA vaccines containing the Ms02 oppA gene, and a preliminary attempt to prove expression of one of these vaccines in a cell culture-based system. The DNA vaccine vectors pCI-neo, VR1012, and VR1020 were chosen for the vaccine development. The Ms02 oppA gene was also cloned into the prokaryotic expression vector pGEX-4T-1 in order to express the OppA protein for purification. The purified protein may be used in future serological tests in ostrich vaccination trials. In this study the protein was used to elicit anti-OppA rabbit antibodies, which were used to attempt detection of the pCI-neo-driven OppA protein expression in an MDA cell line in a transfection study. However, preliminary findings could not detect expression, but did indicate that the currently used colorimetric western blot technique may not be sensitive enough. It is suggested that different cell lines need to be investigated. Further optimisations are also required to decrease the observed non-specific binding.
AFRIKAANSE OPSOMMING: Die Suid-Afrikaanse volstruisbedryf is onder geweldige druk vanweë siektes wat die volstruise bedreig. Die epidemie van die H5N2 virus (voëlgriep) in die afgelope twee jaar het veroorsaak dat duisende volstruise van kant gemaak moes word. Daar is egter nog ‘n bedreiging wat tot geweldige produksie verliese lei elke jaar: die respiratoriese infeksies wat versoorsaak word deur die drie volstruis mikoplasmas, genoem Ms01, Ms02 en Ms03. Geen entstowwe is tans beskibaar om die infeksies te voorkom nie, en behandeling met behulp van antibiotikas is nie effektief in die genesing van infeksie nie, maar help net om die simptome te verlig. Weens die erns van die saak, het die Suid-Afrikaanse volstruisbedryf ‘n ondersoek geloods na die ontwikkeling van enstowwe teen elkeen van die drie volstruis mikoplasmas. Die relatiewe nuwe benadering van DNA-entstof ontwikkeling was die strategiese keuse. Die beginsel van DNA-entstof ontwikkeling berus op die beskikbaarheid van die genoomvolgordes van die siekte-veroorsakende organisme waarteen die enstof ontwikkel word. Geskikte kandidaat entstof gene word so opgespoor met behulp van vergelykende studies met ander beskikbare genome. Die Ms02 genoomvolgorde is voorheen bepaal en word verteenwoordig deur 28 groot geenvolgorde fragmente. Die tegniek van Thermal Asymmetric Interlaced Polymerase Chain Reaction (TAIL-PCR) is gebruik om van die 28 fragmente aan mekaar te las. Die aantal fragmente is verminder na 14 groot geenvolgorde fragmente, wat vervolgens gebruik was om die omvang van herhalende volgordes in die genoom te bepaal, om nuwe leesrame te ondersoek, asook om die oorsprong van DNA replikasie op te spoor met behulp van bioinformatika sagteware. Die omvang van die herhalende aard van die Ms02 genoom word geïllustreer, asook die gepaardgaande probleme met die las van geenvolgorde fragmente wanneer met genome van veelvuldige herhalende volgordes, wat boonop A+T-ryk is, gewerk word, soos die van mikoplasmas. Vorige studies het die mikoplasma oppA geen geïdentifiseer as ‘n geskikte kandidaat entstof geen as gevolg van sy selaanhegting-eienskappe. Hierdie studie behels die invoeging van die Ms02 oppA geen in drie DNA-enstof vektore, naamlik pCI-neo, VR1012, en VR1020, asook die voorlopige poging om bewys van uitdrukking van een van die entstowwe in ‘n selkultuursisteem te bewerkstellig. Die geen is ook gekloneer in die prokariotiese ekspressie vektor pGEX-4T-1, ten einde die Ms02 OppA proteïen te isoleer. Die geïsoleerde proteïen kan in serologiese toetse in toekomstige volstruis enstof proewe gebruik word. In hierdie studie is die proteïen gebruik om konyn teenliggame teen dit op te wek, wat dan gebruik was om vir die pCI-neo-gedrewe ekspressie van die oppA geen te toets in ‘n selkultuur omgewing deur ‘n MDA sellyn te transfekteer. Die voorlopige resultate toon nie ekspressie van die OppA proteïen aan nie, maar het wel uitgelig dat die western blot tegniek wat tans gebruik word, dalk nie sensitief genoeg is nie. Dit kan belowend wees om ander tipes selle te toets. Verdere optimisering is ook nodig om die nie-spesifieke binding wat waargeneem is, te verlaag.
South African Ostrich Business Chamber
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Mulongo, Musa Matsanza. "Evaluation of lipoprotein Q and L-a-glycerol-3-phosphate oxidase of mycoplasma mycoides subs. mycoides (small colony) as virulence factors in contagious bovine pleuropneumonia (CBPP) infections." Thesis, Royal Veterinary College (University of London), 2010. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.558979.
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Mazumder, Anisha. "Analysis of extracts from higher plants to treat diseases." Thesis, University of Ulster, 2012. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.588594.
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Herbal medicine is now globally accepted as an authenticated alternative system of therapy in the form of pharmaceuticals, functional foods, and nutraceuticals; a trend recognized and supported by the World Health Organization (WHO). For decades herbal drugs have shown to be promising for a number of diseases and their use has been supported by physicians and patients for their improved therapeutic benefits as they have less adverse effects when compared with many modern medicines. In this thesis, it was decided to explore the therapeutic potential of n- hexane, DCM and methanol crude extracts from the Nigella sativa plant obtained by using novel Soxhlet extraction. The studies have been conducted on the antibacterial activity of these crude extracts of Nigella sativa and also demonstrated the in vitro antitumour potential of the above crude extracts of the plant. The results indicated that hexane extract of Nigella sativa seeds showed the most potent antibacterial and antitumour activity. The research also aimed at designing novel drug delivery systems for herbal constituent. Lipid emulsion (Intralipid) as a drug carrier was selected to carry the hexane extract obtained from one Soxhlet cycle extraction from the Nigella sativa seeds and determined its antitumour effects. This herbal formulation was investigated using both in vitro and in vivo target systems. Both, in vitro and in vivo findings showed that the Intralipid could carry the active ingredient(s) of the hexane extract across the filtered membrane and the drug carrier (IL) showed the minimal toxicity. Furthermore, the possibility of using ultrasound to enhance the cytotoxicity of the herbal drug formulation was explored using both in vivo and in vitro target system. The results suggested that ultrasound enhanced the therapeutic potential of the antitumour herbal drug in both the systems.
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Sutherland, Margery Louise. "Recognition of host plants by vascular pathogens." Thesis, University of Reading, 1991. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.303155.
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PEPA, A. DELLA. "VECTOR-BORNE DISEASES IN COLONY STRAY CATS OF MILAN CITY." Doctoral thesis, Università degli Studi di Milano, 2013. http://hdl.handle.net/2434/219128.
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LEISHMANIA INFANTUM INFECTION IN STRAY CATS IN A NON-ENDEMIC AREA IN NORTHERN ITALY
E. Spada, DVM, PhD, Researcher 1, A. Della Pepa, DVM 1,
A. Migliazzo, DVM, PhD 2, G. Bagnagatti De Giorgi, DVM 1,
R. Perego, DVM, PhD 1, D. Proverbio, DVM, PhD, Professor 1
1Dipartimento di Scienze Veterinarie per la Salute, la Produzione Animale e
la Sicurezza Alimentare, Universita degli Studi di Milano, Milan, Italy
2Centro di Referenza Nazionale per le Leishmaniosi,Istituto Zooprofilattico
Sperimentale della Sicilia, Palermo, Italy
Tipologia: Ricerca Originale
Area di interesse: Medicina interna
Purpose of the work.
To assess the prevalence of leishmaniosis in a large representative sample of stray cats from this non-endemic area, and to analyze the results according to clinical, laboratory and infectious data
2. MOLECULAR STUDY ON VECTOR-BORNE INFECTIONS IN URBAN STRAY COLONY CAT IN NORTHENRN ITALY
Eva Spada§, DVM, PhD, Researcher
Daniela Proverbio§, DVM, PhD, Professor
Alessandra Della Pepa§, DVM
Paola Galluzzo*, Biologist
Roberta Perego§, DVM, PhD
Giada Bagnagatti De Giorgi§, DVM
Abstract
Feline vector-borne diseases are caused by a wide range of pathogens, which are transmitted by arthropods. Many of these infections have zoonotic implications and feral cats may potentially act as sentinels of human and pet health. The present study investigated the prevalence of vector-borne infections in feral colony cats in the city of Milan in northern Italy. Blood samples from 260 feral cats were evaluated, with conventional PCR, for the presence of DNA associated with hemoplasmas (Mycoplasma haemofelis and Mycoplasma haemominutum), Rickettsia spp., Anaplasma phagocytophilum, Ehrlichia spp. and Babesia microti. Odd ratios (OR) were calculated to identify risk factors for infection with vector-borne pathogens. Positive PCR was found in 156 out of 260 subjects (60%), with a prevalence of 33.1% for hemoplasmas, 31.9% for Rickettsia spp., 17.7% for A. phagocytophilum , 6.7% for Ehrlichia spp. (out of 30 samples), and 1.2% for B. microti spp (out of 168 samples). Statistical analysis revealed a correlation between infections with Rickettsia spp. and hemoplasmas (OR=1.95, P=0.02). Additionally, Rickettsia spp. infection was associated with ocular infection (OR=2.21, P=0.02). We conclude that vector-borne infections, including zoonotic diseases, are present in feral cats of Milan. Thus, domestic cats exposed to the outdoors should be routinely monitored and treated for ectoparasites to minimize disease onset and potential transmission of zoonotic agents to humans. Moreover, as these vector-borne infections are transmitted through blood, feline blood donors from this area should be screened by PCR.
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Wium, Martha. "The development of a DNA vaccine against Mycoplasma nasistruthionis sp. nov. for use in ostriches." Thesis, Stellenbosch : Stellenbosch University, 2015. http://hdl.handle.net/10019.1/97807.
Full textAbstract:
Thesis (PhD)--Stellenbosch University, 2015.ENGLISH ABSTRACT: Mycoplasma nasistruthionis sp. nov. str. Ms03 (Ms03) is one of three Mycoplasma species that were identified from ostriches. Mycoplasmas infections have been implicated in ostrich chick mortalities, growth retardation and downgrading of ostrich carcasses. Currently there is no vaccine available for the treatment of mycoplasmosis in ostriches. This study investigated the development of DNA vaccines against Ms03 infections in ostriches. To this end, the Ms03 genome was sequenced and annotated. The vaccine candidate gene, oppA, was identified within the genome sequence and characterized before DNA vaccines containing the oppA were developed and tested. The genome of Ms03 was sequenced and the resulting 172 contigs were annotated. This dissertation presents the first Ms03 draft genome and annotation which contributed to the understanding of Ms03 as a miniature genetically independent organism. In Ms03, genome replication, cell division, RNA transcription, protein translation and glycolysis resemble that of the closely related Mycoplasma synoviae 53. Purine and pyrimidine metabolism was incomplete and de novo synthesis thereof was not possible. Amino acid synthesis in Ms03 was mostly absent and only the genes that convert aspartate to asparagine and glycine to serine were found. More importers than exporters were annotated owing to the lack of synthesis pathways in Ms03, which is typical for mycoplasmas that have parasitic life styles. Two oligopeptide permease (opp) operons were annotated within the Ms03 genome. The potential of the oppA as a vaccine candidate gene was evaluated by investigating the need for a substrate-binding domain (OppA) as part of the OppBCDF transporter within Mycoplasma species. An oppA homologue could be identified for each oppBCDF operon in all species and therefore must play an essential role in oligopeptide transport. All mycoplasmas (except for hemoplasma) had one, two or three opp operons that could be divided into three types (Type A, B and C). Each type had unique InterPro and MEME domains and motifs which together with the phylogenetic analysis suggest unique roles in their survival under different conditions. Ms03 had a Type A and a Type B opp operon, the Type A oppA was used as vaccine candidate gene. The Type A oppA was cloned and site-directed mutagenesis was used for codon correction before the mutated gene was sub-cloned into three DNA vaccine vectors. The three DNA vaccines (pCI-neo_oppA, VR1012_oppA and VR1020_oppA) were used to vaccinate ostriches and the OppA-antibody response was analysed by ELISA. The VR1020_oppA and pCI-neo_oppA constructs elicited a primary immune response in ostriches, indicating that the OppA protein was expressed in vivo and was immunogenic. This can therefore be viewed as the first step in the development of a DNA vaccine for the control of mycoplasma infections in ostriches.
AFRIKAANSE OPSOMMING: Mycoplasma nasistruthionis sp. nov. str. Ms03 (Ms03) is een van drie mikoplasma spesies wat volstruise infekteer. Mikoplasma-infeksies in volstruise veroorsaak kuiken vrektes, vertraagde groei en afgradering van volstruis karkasse. Daar is tans geen geregistreerde mikoplasma entstof beskikbaar vir gebruik in volstruise nie. Hierdie studie het die ontwikkeling van DNS-entstowwe teen Ms03-infeksies in volstruise ondersoek. Vir hierdie doel was die Ms03-genoomvolgorde bepaal en geannoteer. Die entstofkandidaat-geen, oppA, was geïdentifiseer in die genoomvolgorde en gekarakteriseer voordat DNS-entstowwe (wat die oppA-geen bevat) ontwikkel en getoets is. Die Ms03-genoomvolgorde was bepaal en die gegenereerde 172 aaneenlopende volgordes was geannoteer. Hierdie proefskrif bied die eerste voorlopige volgorde en annotering van die Ms03-genoom wat bygedra het tot die kennis van Ms03 as 'n miniatuur geneties onafhanklike organisme. Genoom-replikasie, seldeling, RNS-transkripsie, proteïen-translasie en glikolise in Ms03 stem ooreen met dié prosesse in die naverwante Mycoplasma synoviae 53. Die purien en pirimidien metabolisme was onvolledig en de novo sintese daarvan was nie moontlik in Ms03 nie. Aminosuursintese in Ms03 was meestal afwesig en net die gene wat aspartaat omskep na asparagien en glisien na serien was gevind in die annoteerde genoom. Meer invoerders as uitvoerders was geannoteer, wat dui op die gebrek aan sintesepadweë in Ms03. Dit is tipies van mikoplasmas wat ‘n parasitiese lewensstyle het. Twee oligopeptied-permeases (opp) operons was gevind in die Ms03-genoom. Die potensiaal van die oppA-geen as 'n entstofkandidaat-geen was geëvalueer deur die behoefte van 'n substraatbindingsdomein (OppA) as deel van die OppBCDF-vervoerder binne mikoplasma spesies te ondersoek. 'n Homoloog van die oppA-geen kon geïdentifiseer word vir elke oppBCDF-operon in al die spesies en behoort daarom 'n noodsaaklike rol te speel in die vervoer van oligopeptiede. Alle mikoplasmas (behalwe vir hemoplasmas) het een, twee of drie opp-operons, wat verdeel kan word in drie tipes (Tipe A, B en C). Elke tipe het unieke InterPro en MEME domeine en motiewe wat saam met die filogenetiese ontleding daarop dui dat hulle unieke rolle in oorlewing onder verskillende omstandighede speel. Ms03 het 'n Tipe A en Tipe B opp-operon, die Tipe A oppA is gebruik as entstofkandidaat-geen. Die Tipe A oppA-geen was gekloneer en teikengerigte-mutagenese was gebruik vir kodonregstellings voordat die gemuteerde geen in drie DNS-entstof vektore gesubkloneer was. Die drie DNS-entstowwe (pCI-neo_oppA, VR1012_oppA en VR1020_oppA) was gebruik om volstruise in te ent en die OppA-teenliggaamsreaksie was geanaliseer deur ELISA. Inenting met die VR1020_oppA en pCI-neo_oppA entstowwe het tot 'n primêre immuniteitsreaksie in volstruise gelei. Dit dui daarop dat die OppA proteïen in vivo uitgedruk en immunogenies was. Dit kan beskou word as die eerste stap in die ontwikkeling van 'n DNS-entstof vir die beheer van mikoplasma-infeksies in volstruise.
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Rodriguez, Juan Jose. "Movement and Accumulation of Candidatus Liberibacter Solanacearum in Potato Plants." Diss., North Dakota State University, 2012. https://hdl.handle.net/10365/26726.
Full textAbstract:
A new disease affecting potatoes was first detected in Mexico in 1993. Affected plants had aerial symptoms similar to those caused by potato purple top and psyllid yellows, but tubers had internal brown discoloration when sliced and dark stripes and streaks when processed to produce potato chips. The disease has been found in many potato production areas in Guatemala, Mexico, Honduras, New Zealand and the United States. The disease, termed Zebra Chip (ZC), has been associated with the presence of heavy infestations of the potato-tomato psyllid (Bactericera cockerelli). In 2009, a research group in New Zealand discovered that a new disease in tomato and pepper plants was caused by Candidatus Liberibacter solanacearum (Lso) and subsequently this same bacterium was associated with ZC in potato samples from Texas. The objectives of this study were: to assess the accumulation of Lso in various potato organs, to determine the effect of plant age on detection of Lso, symptom development and plant death, and (iii) to determine the effect of phosphorous acid on the development of ZC. Results from these studies showed significant differences in Lso populations between above and below ground tissues of the potato plant, with Lso populations in stolons and tubers being three to four times higher than those of leaf tissue and over seventy times greater than in stems. Time for detection of Lso by PCR in potato leaves of different ages at the time of inoculation ranged from 21 to 26 days after inoculation, symptoms development took 23 to 36 days. Plant death, took 24 to 47 days in plants of different age groups at the time of inoculation. In plants 15 weeks old at the time of inoculation, Lso was detected after 14 days in one plant out of 18; in plants 16 weeks old at the time of inoculation, Lso was detected after seven days in two plants out of 18. Phosphorous acid applications had no effect on the populations of Lso in potato tubers, onset of symptoms or plant death. All tubers showed ZC symptoms, making them unacceptable for the market.North Dakota State University. Department of Plant Pathology
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Knowles, Cindy-Lee. "Synergistic effects of mixtures of the kresoxim-methyl fungicide and medicinal plants extracts in vitro and in vivo against Botrytis Cinerea." Thesis, University of the Western Cape, 2005. http://etd.uwc.ac.za/index.php?module=etd&.
Full textAbstract:
The fungus Botrytis cinerea is an opportunistic pathogen on a wide variety of crops, causing disease known as grey mould through infections via wounds or dead plant parts. Synthetic fungicides for controlling this disease are fast becoming ineffective due to the development of resistance. This, coupled with consumers world wide becomng increasingly conscious of potential environment and health problems associated with the build up of toxic chemicals, (particularly in food products), have resulted in pressure to reduce the use of chemical pesticide volumes as well as its residues. An emerging alternative to random synthesis is the study and exploitation of naturally occurring products with fungicidal properties. There have been reports on the uses of synthetic fungicides for the control of plant pathogenic fungi. When utilized in two-way mixtures, such fungicides may maintain or enhance the level of control of a pathogen at reduced rates for both components utilized in combinations, or alone at normal rates. For this study it was hypothesize that the addition of plant extracts may enhance the antifungal efficacy of the synthetic strobilurin fungicide, kresoxim-methyl against Botrytis cinerea.
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Agawane, S. B. "Chemo-biological evaluation of few medicinal plants against various diseases." Thesis(Ph.D.), CSIR-National Chemical Laboratory, Pune, 2018. http://dspace.ncl.res.in:8080/xmlui/handle/20.500.12252/4596.
Full text
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Carrington, Christopher Antony Paul. "The role of Mycoplasma species in bovine respiratory disease complex in feedlot cattle in South Africa." Electronic thesis, 2007. http://upetd.up.ac.za/thesis/available/etd-10312007-150332/.
Full text
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Wang, Kay Yee. "Mycoplasma pneumoniae and Bordetella pertussis in patients with persistent cough in primary care." Thesis, University of Oxford, 2012. http://ora.ox.ac.uk/objects/uuid:74b15a97-708d-4927-b0aa-ce802f4af2aa.
Full textAbstract:
Background: Persistent cough following an acute respiratory tract infection is a challenging and frequently encountered problem in primary care. Mycoplasma pneumoniae (M. pneumoniae) and Bordetella pertussis (pertussis) particularly predispose patients to persistent cough. Whilst the incidence of M. pneumoniae is highest in children, pertussis may also occur in adults. Method: Four studies were conducted for this thesis. First, a systematic review to assess the diagnostic accuracy of symptoms and signs in the clinical recognition of M. pneumoniae. Second, a retrospective analysis of a cohort of children with persistent cough to assess the prognostic value of diagnosing M. pneumoniae. Third, a prospective cohort study to estimate the prevalence of M. pneumoniae and pertussis in children with persistent cough following recent changes in vaccination policy. Fourth, a double-blind randomised placebo-controlled trial to determine the effectiveness of montelukast in the treatment of persistent cough and pertussis-induced cough in adults. Results: M. pneumoniae and pertussis can each be found in one-sixth of children who present in primary care with persistent cough. Although coverage with the preschool pertussis booster vaccine is high, its efficacy wanes rapidly, with the likelihood of pertussis increasing by 30% per year after vaccination. Montelukast is not an effective treatment for persistent cough, but may be an effective treatment for pertussis-induced cough. Median duration of cough in children with M. pneumoniae is only one-third of that in children with pertussis (39 days versus 118 days). However, the diagnostic accuracy of symptoms and signs in the clinical recognition of M. pneumoniae is limited. Since M. pneumoniae occurs in cyclical epidemics, clinicians should consider current prevalence of M. pneumoniae when making a clinical diagnosis. Conclusions: Diagnosing M. pneumoniae and pertussis can help clinicians give patients an explanation for their cough and inform them about its likely prognosis. At the moment, clinicians should adopt a conservative approach to managing postinfectious persistent cough. A further trial is needed to assess the efficacy of montelukast for the treatment of pertussis-induced cough.
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Saqib, Muhammad. "Studies on new plant phytoplasma and viruses infections and molecular dissection of virus resistance using Medicago truncatula." Thesis, Saqib, Muhammad (2008) Studies on new plant phytoplasma and viruses infections and molecular dissection of virus resistance using Medicago truncatula. PhD thesis, Murdoch University, 2008. https://researchrepository.murdoch.edu.au/id/eprint/288/.
Full textAbstract:
The work presented in this thesis is in two areas - study of novel pathogens resulting from new encounters between crop and native species and 'mining' for plant virus resistance genes in the model legume Medicago truncatula.
The history of agriculture in Western Australia (WA) is less than 150 years old. All major broadacre and horticultural crops grown in WA have been introduced from overseas. These introduced horticultural and field crops potentially carry pathogens which may be transferred to infect native vegetation. Conversely, cultivated plants are vulnerable to infection by pathogens present in indigenous plants. This potential for new disease encounters is compounded by expansion of agriculture to crop new land and by predicted climate changes. These changes may provide selective advantage to a particular pest or disease, enabling infection to increase and so increase crop losses or damage native species. Global trade in agricultural produce also increases the potential for introduction of exotic pathogens. The focus of the first part of the research was to look for new pathogens of crops and native plants in WA.
A series of field trips to study diseases in horticultural crops and native vegetation were made in the agricultural regions of Carnarvon, Broome, Kununurra, Perth and the surrounding metropolitan area. Although the initial focus was on virus diseases, the work expanded to study phytoplasma-associated diseases, because of their widespread occurrence and clear symptoms.
In the agricultural region around Kununurra the potyvirus Bean common mosaic virus (BCMV) was found infecting Phaseolus vulgaris crops. Sequencing of isolates collected provided the first reliable molecular confirmation of the presence of BCMV in Australia.
In joint work with K. Bayliss three commercial Paulownia tree plantations near Perth were found exhibiting symptoms of Witches'-Broom disease. The Paulownia trees were found to be associated with 'Candidatus Phytoplasma australiense' 16SrXII group. Chickpeas in the Kununurra region were found with symptoms of stunting, little leaf and proliferating branches and tested positive for phytoplasma. Sequencing confirmed the presence of a phytoplasma with high similarity to the 16SrII group 'Ca Phytoplasma aurantifolia' (peanut witches broom group). This is the first molecular evidence for a phytoplasma-associated disease in chickpea. Red clover (Trifolium pratense), several other pasture legumes and paddy melon (Cucumis myriocarpus) with symptoms of diminished leaf size, pallor, rugosity, leaf deformation, shoot proliferation and stunting were observed amongst pasture plots in south-western Australia. All species with these symptoms were positive for a phytoplasma resembling 'Ca Phytoplasma australiense, 16SrXII group. This association was confirmed for red clover and paddy melon by subsequent nested PCR and sequence analysis. This is the first time that 'Ca. Phytoplasma australiense, 16SrXII group, has been reported infecting these hosts in southern WA. Snakebean (Vigna unguiculata var. sesquipedalis) and tomato (Lycopersicon esculentum) plants with phytoplasma-like symptoms were found in the horticultural region at Broome. The symptoms on snakebean were typical of phytoplasma disease. Sequence analysis identified that the agent associated with the symptoms as a strain of sweet potato little leaf strain V4 (SPLL-V4) phytoplasma (16SrXII group, strain of 'Ca Phytoplasma australiense'). SPLL phytoplasma has not been reported in snakebean or tomato in this isolated agricultural region. In a survey in the Gascoyne region phytoplasma-like symptoms were found in tomato, eggplant and papaya. Previously in this region plants had been found to be associated with peanut witches broom phytoplasma 16SrII group 'Ca Phytoplasma aurantifolia'. Phytoplasma-like symptoms which included bunchy growth, witches' broom and 'little leaf' were observed in Allocasuarina fraseriana (Western Sheoak, Casuarina) and Acacia saligna (Acacia, Orange Wattle) trees in Kings Park and Botanic Garden Perth WA. Phytoplasma-associated disease was confirmed for the first time in native Australian casuarina and acacia trees in WA. Based on the identification of these phytoplasma associated diseases in WA, phytoplasma-associated diseases can be divided into two zones, because phytoplasma 16SrII group was found mostly in the north west of WA and the 16SrXII group in the south west of WA. This work has added to knowledge of the extent and distribution of phytoplasma disease in WA: it is concluded that crop-associated phytoplasma disease originated from native vegetation.
The aim of the second part of the research was to screen and map a virus resistance gene in the model legume M. truncatula to better understand host/pathogen interactions of legume-infecting viruses. Natural resistance genes found in M. truncatula could then be used to locate similar genes in grain legumes (e.g. chickpea and lupins) for practical applications. M. truncatula is a model legume which has a relatively small genome. International consortia have been established to develop genomic resources for M. truncatula. The M. truncatula core collection (from SARDI, South Australia) totalling 230 accessions was screened for resistance/susceptibility to four legume-infecting viruses: Alfalfa mosaic virus (AMV), Cucumber mosaic virus (CMV), Bean yellow mosaic virus (BYMV) and Subterranean clover mottle virus (SCMoV). Five plants from each of the 230 phenotypically distinct members of the M. truncatula core collection were challenged with one isolate of each virus using infectious sap together with five uninoculated control plants for each accession. The symptoms that developed were recorded and virus presence was confirmed by ELISA for inoculated and systemic leaves. Accessions that were potentially resistant were retested to check for escapes. The result from this screen was that 5 accessions were potentially resistant to AMV, 56 to BYMV, 21 to CMV and 42 to SCMoV. The remaining accessions were susceptible to all four viruses with symptoms which ranged from no apparent symptoms (symptomless systemic infection) to highly susceptible and plant death. In continuing work with DAFWA (Dr R. Jones) accessions potentially resistant to AMV, BYMV and CMV are being challenged with additional isolates to check for the presence of genes providing broader resistance.
The Sobemovirus SCMoV was chosen for further study because it is the most widespread viral pathogen of subterranean clover pastures in Australia. It is also a high titre, mechanically transmitted virus which gave the least escapes on infection. SCMoV has a linear, single-stranded positive-sense RNA genome of 4.25 Kb. Making use of natural resistance is an effective means to reduce pasture losses caused by SCMoV. From the screen of the core collection of M. truncatula, amongst the lines resistant to SCMoV a single dominant hypersensitive resistance was detected in line DZA-315. To accelerate mapping of the SCMoV resistance gene, an F8 RIL population of a cross between the resistant line (DZA-315) and a susceptible line (Jemalong-J6, A-17) was sourced and obtained from INRA Toulouse. A total of 166 RILs were phenotyped for resistance and susceptibility to SCMoV. Resistant and susceptible lines showed parental phenotypic symptoms with 84 being susceptible and 82 being resistant. This indicated the presence of a single resistance (R) gene. This phenotypic data was combined with genotypic data (76 polymorphic molecular markers) already available for this RIL population to provide a framework map. Mapmaker and Mapmanager mapping programs were used to locate the position of the resistance gene. This framework map indicated a position for the resistance gene on the long arm of chromosome 6.
Additional polymorphic SSR markers flanking the R gene locus on chromosome 6 were used to map the position of the R gene more closely. These SSR markers were developed from a parental cross of M. truncatula line A17 and A20 at UC Davis and from a parental cross between line A17 and DZA 315 developed at INRA Toulouse. Ten new polymorphic SSR markers were identified and located on the long arm of chromosome 6 after analysis of the F8 RIL population. When combined with the other phenotypic and genotypic data a more accurate map position for the SCMoV R gene was obtained. The results indicate that the R gene to SCMoV is located on the long arm of M. truncatula chromosome 6 between position 35 to 38 centimorgans (cM). The closest marker to the SCMoV R gene is marker mtic153 which is about 2.3 cM away. From existing maps of M. truncatula most of the R genes located in this region are of the TIR-NBS-LRR type and occur in R gene clusters. A series of BACs that span the region of interest have been identified in which SCMoV R gene should be present.
M. truncatula has been used as a model legume to study a number of symbiotic (e.g. rhizobium) and pathogenic interactions (e.g. fungal and nematode), but this is the only example of its use to study legume-virus interactions. The results obtained indicate the potential of using M. truncatula as a model to study resistance response to other legume viruses and provide a firm basis for identifying the hypersensitive R gene that confers resistance to SCMoV.
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Saqib, Muhammad. "Studies on new plant phytoplasma and viruses infections and molecular dissection of virus resistance using Medicago truncatula." Saqib, Muhammad (2008) Studies on new plant phytoplasma and viruses infections and molecular dissection of virus resistance using Medicago truncatula. PhD thesis, Murdoch University, 2008. http://researchrepository.murdoch.edu.au/288/.
Full textAbstract:
The work presented in this thesis is in two areas - study of novel pathogens resulting from new encounters between crop and native species and 'mining' for plant virus resistance genes in the model legume Medicago truncatula.
The history of agriculture in Western Australia (WA) is less than 150 years old. All major broadacre and horticultural crops grown in WA have been introduced from overseas. These introduced horticultural and field crops potentially carry pathogens which may be transferred to infect native vegetation. Conversely, cultivated plants are vulnerable to infection by pathogens present in indigenous plants. This potential for new disease encounters is compounded by expansion of agriculture to crop new land and by predicted climate changes. These changes may provide selective advantage to a particular pest or disease, enabling infection to increase and so increase crop losses or damage native species. Global trade in agricultural produce also increases the potential for introduction of exotic pathogens. The focus of the first part of the research was to look for new pathogens of crops and native plants in WA.
A series of field trips to study diseases in horticultural crops and native vegetation were made in the agricultural regions of Carnarvon, Broome, Kununurra, Perth and the surrounding metropolitan area. Although the initial focus was on virus diseases, the work expanded to study phytoplasma-associated diseases, because of their widespread occurrence and clear symptoms.
In the agricultural region around Kununurra the potyvirus Bean common mosaic virus (BCMV) was found infecting Phaseolus vulgaris crops. Sequencing of isolates collected provided the first reliable molecular confirmation of the presence of BCMV in Australia.
In joint work with K. Bayliss three commercial Paulownia tree plantations near Perth were found exhibiting symptoms of Witches'-Broom disease. The Paulownia trees were found to be associated with 'Candidatus Phytoplasma australiense' 16SrXII group. Chickpeas in the Kununurra region were found with symptoms of stunting, little leaf and proliferating branches and tested positive for phytoplasma. Sequencing confirmed the presence of a phytoplasma with high similarity to the 16SrII group 'Ca Phytoplasma aurantifolia' (peanut witches broom group). This is the first molecular evidence for a phytoplasma-associated disease in chickpea. Red clover (Trifolium pratense), several other pasture legumes and paddy melon (Cucumis myriocarpus) with symptoms of diminished leaf size, pallor, rugosity, leaf deformation, shoot proliferation and stunting were observed amongst pasture plots in south-western Australia. All species with these symptoms were positive for a phytoplasma resembling 'Ca Phytoplasma australiense, 16SrXII group. This association was confirmed for red clover and paddy melon by subsequent nested PCR and sequence analysis. This is the first time that 'Ca. Phytoplasma australiense, 16SrXII group, has been reported infecting these hosts in southern WA. Snakebean (Vigna unguiculata var. sesquipedalis) and tomato (Lycopersicon esculentum) plants with phytoplasma-like symptoms were found in the horticultural region at Broome. The symptoms on snakebean were typical of phytoplasma disease. Sequence analysis identified that the agent associated with the symptoms as a strain of sweet potato little leaf strain V4 (SPLL-V4) phytoplasma (16SrXII group, strain of 'Ca Phytoplasma australiense'). SPLL phytoplasma has not been reported in snakebean or tomato in this isolated agricultural region. In a survey in the Gascoyne region phytoplasma-like symptoms were found in tomato, eggplant and papaya. Previously in this region plants had been found to be associated with peanut witches broom phytoplasma 16SrII group 'Ca Phytoplasma aurantifolia'. Phytoplasma-like symptoms which included bunchy growth, witches' broom and 'little leaf' were observed in Allocasuarina fraseriana (Western Sheoak, Casuarina) and Acacia saligna (Acacia, Orange Wattle) trees in Kings Park and Botanic Garden Perth WA. Phytoplasma-associated disease was confirmed for the first time in native Australian casuarina and acacia trees in WA. Based on the identification of these phytoplasma associated diseases in WA, phytoplasma-associated diseases can be divided into two zones, because phytoplasma 16SrII group was found mostly in the north west of WA and the 16SrXII group in the south west of WA. This work has added to knowledge of the extent and distribution of phytoplasma disease in WA: it is concluded that crop-associated phytoplasma disease originated from native vegetation.
The aim of the second part of the research was to screen and map a virus resistance gene in the model legume M. truncatula to better understand host/pathogen interactions of legume-infecting viruses. Natural resistance genes found in M. truncatula could then be used to locate similar genes in grain legumes (e.g. chickpea and lupins) for practical applications. M. truncatula is a model legume which has a relatively small genome. International consortia have been established to develop genomic resources for M. truncatula. The M. truncatula core collection (from SARDI, South Australia) totalling 230 accessions was screened for resistance/susceptibility to four legume-infecting viruses: Alfalfa mosaic virus (AMV), Cucumber mosaic virus (CMV), Bean yellow mosaic virus (BYMV) and Subterranean clover mottle virus (SCMoV). Five plants from each of the 230 phenotypically distinct members of the M. truncatula core collection were challenged with one isolate of each virus using infectious sap together with five uninoculated control plants for each accession. The symptoms that developed were recorded and virus presence was confirmed by ELISA for inoculated and systemic leaves. Accessions that were potentially resistant were retested to check for escapes. The result from this screen was that 5 accessions were potentially resistant to AMV, 56 to BYMV, 21 to CMV and 42 to SCMoV. The remaining accessions were susceptible to all four viruses with symptoms which ranged from no apparent symptoms (symptomless systemic infection) to highly susceptible and plant death. In continuing work with DAFWA (Dr R. Jones) accessions potentially resistant to AMV, BYMV and CMV are being challenged with additional isolates to check for the presence of genes providing broader resistance.
The Sobemovirus SCMoV was chosen for further study because it is the most widespread viral pathogen of subterranean clover pastures in Australia. It is also a high titre, mechanically transmitted virus which gave the least escapes on infection. SCMoV has a linear, single-stranded positive-sense RNA genome of 4.25 Kb. Making use of natural resistance is an effective means to reduce pasture losses caused by SCMoV. From the screen of the core collection of M. truncatula, amongst the lines resistant to SCMoV a single dominant hypersensitive resistance was detected in line DZA-315. To accelerate mapping of the SCMoV resistance gene, an F8 RIL population of a cross between the resistant line (DZA-315) and a susceptible line (Jemalong-J6, A-17) was sourced and obtained from INRA Toulouse. A total of 166 RILs were phenotyped for resistance and susceptibility to SCMoV. Resistant and susceptible lines showed parental phenotypic symptoms with 84 being susceptible and 82 being resistant. This indicated the presence of a single resistance (R) gene. This phenotypic data was combined with genotypic data (76 polymorphic molecular markers) already available for this RIL population to provide a framework map. Mapmaker and Mapmanager mapping programs were used to locate the position of the resistance gene. This framework map indicated a position for the resistance gene on the long arm of chromosome 6.
Additional polymorphic SSR markers flanking the R gene locus on chromosome 6 were used to map the position of the R gene more closely. These SSR markers were developed from a parental cross of M. truncatula line A17 and A20 at UC Davis and from a parental cross between line A17 and DZA 315 developed at INRA Toulouse. Ten new polymorphic SSR markers were identified and located on the long arm of chromosome 6 after analysis of the F8 RIL population. When combined with the other phenotypic and genotypic data a more accurate map position for the SCMoV R gene was obtained. The results indicate that the R gene to SCMoV is located on the long arm of M. truncatula chromosome 6 between position 35 to 38 centimorgans (cM). The closest marker to the SCMoV R gene is marker mtic153 which is about 2.3 cM away. From existing maps of M. truncatula most of the R genes located in this region are of the TIR-NBS-LRR type and occur in R gene clusters. A series of BACs that span the region of interest have been identified in which SCMoV R gene should be present.
M. truncatula has been used as a model legume to study a number of symbiotic (e.g. rhizobium) and pathogenic interactions (e.g. fungal and nematode), but this is the only example of its use to study legume-virus interactions. The results obtained indicate the potential of using M. truncatula as a model to study resistance response to other legume viruses and provide a firm basis for identifying the hypersensitive R gene that confers resistance to SCMoV.
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Cole, Anthony Blaine Thomas. "Investigations into the hypersensitive response of Nicotiana species to virus infections /." free to MU campus, to others for purchase, 2001. http://wwwlib.umi.com/cr/mo/fullcit?p3012960.
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Yu, Weichang. "CAMV gene VI protein : a virulence factor and the host responses in Arabidopsis /." free to MU campus, to others for purchase, 2002. http://wwwlib.umi.com/cr/mo/fullcit?p3075411.
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Jurstrand, Margaretha. "Detection of Chlamydia trachomatis and Mycoplasma genitalium by genetic and serological methods." Doctoral thesis, Örebro : Universitetsbiblioteket : Örebro University, 2006. http://urn.kb.se/resolve?urn=urn:nbn:se:oru:diva-793.
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Pakela, Yolisa Patronella. "Interaction between Colletotrichum dematium and cowpea." Thesis, Pretoria: [s.n.], 2003. http://upetd.up.ac.za/thesis/available/etd-09022005-102127/.
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Denman, Sandra. "Botryosphaeria diseases of proteaceae." Thesis, Stellenbosch : Stellenbosch University, 2002. http://hdl.handle.net/10019.1/52721.
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Dissertation (PhD (Agric))--University of Stellenbosch, 2002.ENGLISH ABSTRACT: Fungi belonging to the genus Botryosphaeria are heterotrophic micromycetes that can be pathogens on woody plants. They cause serious, and in some cases devastating losses to crops through leaf necrosis, stem cankers and plant death. The Proteaceae cut-flower industry in South Africa accounts for 70% of the national cut-flower enterprise. Botryosphaeria diseases are a major impediment to production and trade of Proteaceae and there is an urgent need to investigate the etiology, epidemiology and control of these diseases. Losses of one of the most important proteas, P. magnifica, amount to 50% or more, locally. The main aims of this study were therefore to establish the etiology and aspects of epidemiology of Botryosphaeria stem cankers on P. magnifica and other Proteaceae, and to investigate methods of disease control. Although there is a vast body of information pertaining to this fungus, which was reviewed in Chapter 1, there is relatively little information available on Botryosphaeria on Proteaceae. The taxonomy of Botryosphaeria requires thorough review, and molecular techniques need to be employed to resolve species identities. In Chapter 2, it was found that Phyllachora proteae, a leaf pathogen of proteas, produced a Fusicoccum anamorph, which is described as F. proteae. A sphaeropsis-like synanamorph was associated with F. proteae and a new combination for P. proteae is proposed in Botryosphaeria, as B. proteae. The taxonomy of Botryosphaeria is in disarray at both the generic and the specific level. In Chapter 3 the taxonomic history of Botryosphaeria is reviewed, and the genus circumscribed and distinguished from other morphologically similar genera. Although several anamorph genera have been linked to Botryosphaeria, based on morphological observations and phylogenetic analysis of lTS rDNA sequence data, two anamorph genera are now recognised, those with pigmented conidia (Diplodia), and those with hyaline conidia (Fusicoccum). Botryosphaeria proteae should thus be excluded from Botryosphaeria. Several pathogenic Botryosphaeria spp. have an endophytic phase within their hosts. They are therefore imported unwittingly into other countries where they may pose a risk to agriculture and indigenous vegetation. The current global distribution of Botryosphaeria spp. associated with Proteaceae is clarified and a key to these taxa associated with Proteaceae is provided in Chapter 4. Five Botryosphaeria spp. are associated with cut-flower Proteaceae worldwide viz. B. lute a, B. obtusa, B. protearum, B. proteae and B. rib is. B. protearum is described as a new species. A thorough understanding of disease epidemiology is essential to effect a reduction of losses. In Chapter 5, I show that on P. magnifica, lesions caused by Botryosphaeria protearum, which lead to the formation of stem cankers, are initiated in the mid-rib vein or margin of leaves. Koch's postulates were satisfied and it was found that the number of lesions that developed from artificial inoculations correlated with starch levels present in leaves at the time of inoculation. In Chapter 6 it is shown that B. protearum exists as an endophyte in leaves of P. magnifica in naturally occurring as well as cultivated plants. In natural stands of proteas stem cankers are rare, but in cultivated plantations the incidence is high. Nutritional analyses indicate that higher levels of nitrogen occur in leaves of cultivated plants in spring, which could enhance disease development. High levels of sodium in the leaves of wild plants may restrict disease development. The severe economic losses caused by B. protearum make the search for improved methods of disease control essential. Fungicide applications form an important component of an integrated approach to disease management. In Chapter 7, in vitro tests demonstrate that tebuconazole, benomyl, prochloraz me, iprodione and fenarimol reduce the mycelial growth of B. protearum effectively. In the field there was a 25-85% reduction in the occurrence of stem cankers by applying fungicides or sanitation pruning. The best control was achieved by using benomyl, bitertanol, fenarimol, iprodione, prochloraz manganese chloride alternated with mancozeb and tebuconazole prophylactically. If sanitation pruning is combined with regular applications of fungicides, disease can be combated.
AFRIKAANSE OPSOMMING: Mikrofungi wat tot die genus Botryosphaeria behoort, is heterotrofiese organismes, wat patogenies op houtagtige plante kan wees. Hulle veroorsaak ernstige, en in sommige gevalle, verwoestende verliese, deur blaarnekrose, stamkankers en plantafsterwing. Die Proteaceae snyblom-industrie in Suid-Afrika maak 70% van die nasionale snyblomindustrie uit. Botryosphaeria siektes is 'n belangrike struikelblok in die produksie en handeldryf van Proteaceae, en daar is 'n ernstige behoefte om die etiologie, epidemiologie en beheer van siektes te ondersoek. Verliese van een van die belangrikste proteas, P. magnifica, beloop plaaslik 50% of meer. Die hoof doelstellings van hierdie studie was dus om die etiologie en epidemiologie van Botryosphaeria stamkankers op P. magnifica en ander Proteaceae vas te stel en metodes van siektebeheer te ondersoek. Hoewel daar 'n wye hoeveelheid inligting rakende die swam bestaan, wat in Hoofstuk I hersien is, is daar relatief min inligting oor Botryosphaeria op Proteaceae beskikbaar. Die taksonomie van Botryosphaeria benodig deeglike hersiening, en molekulêre tegnieke word benodig om spesie-identiteite op te klaar. In Hoofstuk 2 is gevind dat Phyllachora proteae, 'n blaarpatogeen van proteas, 'n Fusicoccum anamorf produseer, wat as F. proteae beskryf word. 'n Sphaeropsis-agtige synanamorf is met F. proteae geassosieer en 'n nuwe kombinasie vir P. proteae is as B. proteae in Botryosphaeria voorgestel. Die taksonomie van Botryosphaeria is, beide op die genus- as die spesievlak, in wanorde. In Hoofstuk 3 word die taksonomiese geskiedenis van Botryosphaeria hersien, en die genus word omskryf en van ander morfologies soortgelyke genera onderskei. Hoewel verskeie anamorf genera al met Botryosphaeria op grond van morfologiese waarnemings en filogenetiese analise van ITS rDNA volgorde data verbind is, word twee anamorf genera nou herken, dié met gepigmenteerde konidia (Diplodia), en dié met deurskynende konidia (Fusicoccum). Botryosphaeria proteae moet dus van Botryosphaeria uitgesluit word. Verskeie patogeniese Botryosphaeria spp. het 'n endofitiese fase in hul lewenssiklus. Hulle word dus onwetend in ander lande ingevoer waar hulle 'n gevaar vir landbou en inheemse plantegroei kan inhou. Die huidige wêreldverspreiding van Botryosphaeria spp. wat met Proteaceae geassosieer word is opgeklaar, en in Hoofstuk 4 word 'n sleutel tot die taksa wat met Proteaceae geassosieer word verskaf. Vyf Botryosphaeria spp. word met snyblom Proteaceae wêreldwyd geassosieer, naamlik B. lutea, B. protearum, B. proteae, B. ribis en B. obtusa. B. protearum word as 'n nuwe spesie beskryf. 'n Deeglike kennis van siekte-epidemiologie is noodsaaklik ten einde verliese te verminder. In Hoofstuk 5 dui ek aan dat letsels wat lei tot stamkankers, veroorsaak deur Botryosphaeria protearum op P. magnifica, in die hoofnerf of rant van blare ontstaan. Koch se postulate is uitgevoer en daar is vasgestel dat die aantal letsels wat vanuit kunsmatige inokulasies ontwikkel het korreleer met die styselvlakke teenwoordig in die blare ten tye van die inokulasie. In Hoofstuk 6 word getoon dat B. protearum as 'n endofiet in die blare van P. magnifica. In natuurlike standplase van proteas is stamkankers skaars, maar in verboude plantasies is die voorkoms hoog. Voedingsanalises dui aan dat hoër vlakke van stikstof in die blare van verboude plante in die lente voorkom, wat siekte-ontwikkeling moontlik kan bevorder. Hoë vlakke van natrium in die blare van natuurlike plante mag siekteontwikkeling beperk. Die ernstige ekonomiese verliese wat deur B. protearum veroorsaak word, maak die soektog na verbeterde metodes van siektebeheer noodsaaklik. Fungisiedtoedienings maak 'n belangrike deel uit van 'n geïntegreerde benadering tot siektebeheer. In Hoofstuk 7 dui in vitro toetse aan dat tebuconazole, benomyl, prochloraz me, iprodione en fenarimol die miseliumgroei van B. protearum effektief verminder. 'n Vermindering van 25-85% is aangetoon in die voorkoms van stamkankers in die veld, deur die toediening van fungisiedes en sanitasiesnoei. Die beste beheer is verkry deur die voorkomende toediening van benomyl, bitertanol, fenarimol, iprodione en prochloraz manganese chloride, afgewissel met mancozeb en tebuconazole, op plante in die veld. Indien sanitasiesnoei met gereelde toedienings van fungisiedes gekombineer word, kan die siekte bekamp word.
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Waters, Ormonde Dominick Creagh. "Metabolism and infection in the Stagonospora nodorum-wheat pathosystem /." Murdoch University Digital Theses Program, 2008. http://wwwlib.murdoch.edu.au/adt/browse/view/adt-MU20090409.123159.
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Ghanem, Mostafa Ghanem Ahmed. "Development of Advanced Molecular Tools for Sequence Typing and Epidemiological Investigation of Avian Mycoplasma in Poultry." The Ohio State University, 2017. http://rave.ohiolink.edu/etdc/view?acc_num=osu1492527446411409.
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McGovern, Kristen B. "Evaluation of Potential Organic Controls of Mummy Berry Disease Affecting Lowbush Blueberry in Maine." Fogler Library, University of Maine, 2007. http://www.library.umaine.edu/theses/pdf/McGovernKB2007.pdf.
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Falk, Lars. "Urethritis and cervicitis with special reference to Chlamydia trachomatis and Mycoplasma genitalium : diagnostic and epidemiological aspects /." Linköping : Univ, 2004. http://www.bibl.liu.se/liupubl/disp/disp2004/med858s.pdf.
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Arthur, Fareed Kow Nanse. "Defense responses to fungal challenge in alfalfa (medicago sativa L.) plants and tissue cultures." Thesis, University of Nottingham, 1994. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.385239.
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Király, Lóránt. "Interactions between cauliflower mosaic virus isolates and nicotiana species that determine systemic necrosis /." free to MU campus, to others for purchase, 1997. http://wwwlib.umi.com/cr/mo/fullcit?p9841160.
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Jeffries, Alex Craig. "The study at the molecular level of the New Zealand isolate of Lucerne transient streak sobemovirus and its satellite RNA." Title page, contents and summary only, 1993. http://web4.library.adelaide.edu.au/theses/09PH/09phj47.pdf.
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Kimani, Esther Wairimu. "Serological detection of Didymella lycopersici (Kleb.)." Thesis, University of British Columbia, 1990. http://hdl.handle.net/2429/29190.
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Polyclonal antisera produced against spores, soluble protein and the whole mycelium fractions of Didymella lycopersici reacted with the homologous and heterologous antigens. The most sensitive antiserum was that raised against the whole mycelium, the soluble protein and the spore, in decreasing order of sensitivity. Using the antiserum raised against the whole mycelium it was possible to detect D. lycopersici on diseased plants and infested seeds. Cross reactivity was observed between the antisera produced to D. lycopersici and D. applanata, D. bryoniae and other tomato fungal pathogens including Fusarium spp. and B. cinerea. ELISA was most sensitive and reliable compared to double immunodiffusion, and latex tests. No reactions were obtained using the latex agglutination procedure and no antiserum detected spores in double diffusion tests.
Protein profiles on SDS-PAGE revealed that the total number of protein bands decreased with increased age of cultures of D. lycopersici incubated in liquid media. Western blots probed with the antiserum raised against the whole mycelium showed that protein bands from extracts of both D. lycopersici and D. applanata were antigenic.Land and Food Systems, Faculty of
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MacDonald, Stuart Gerald. "Two viruses associated with blueberry scorch disease." Thesis, University of British Columbia, 1989. http://hdl.handle.net/2429/29421.
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Blueberry bushes with scorch symptoms were found during a survey of blueberry fields in British Columbia, Washington, and Oregon. Some of these bushes were infected with blueberry scorch virus (BBScV) while others contained a second virus which was sap transmissible to Nicotiana clevelandii, N. benthamiana, and N. tabacum cv. 'Havana 425' . This virus was purified from N. clevelandii and had isometric particles of approximately 30 nm in diameter, a coat protein subunit of 27,500 daltons and a tripartite genome. I was unable to transfer the virus from either infected N. clevelandii or infected blueberry to healthy N. clevelandii with Myzus persicae or Fimbriaphis fimbriata. Serological tests of this blueberry virus with antisera against members of the ilar-, cucumo-, bromo-, or nepovirus groups failed to indicate any relationship. In a subsequent survey using enzyme-linked immunosorbent assay, this isometric virus was found in blueberry plants from northern Washington state to central Oregon but has not yet been found in B.C.
Of the established members of the carlavirus group examined, BBScV is most closely related to potato virus S (PVS) and less closely related to carnation latent virus (CLV) and potato virus M (PVM). The difference in host range between BBScV and PVS would indicate that the BBScV is not a strain of PVS but is a separate virus that is related to PVS. Therefore, BBScV should be renamed blueberry scorch carlavirus (BBSCV).
BBSCV was also compared to a carlavirus isolated from blueberry in the Sheep Pen Hill blueberry growing area of New Jersey (referred to as SPHV). These viruses were compared serologically and by use of nucleic acid hybridizations. BBSCV and SPHV were found to be closely related and were concluded to be strains of the same virus. SPHV should be named the New Jersey strain of BBSCV.Land and Food Systems, Faculty of
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Liu, X. Q. (Xingquan). "Differentiation of garlic viruses." Thesis, McGill University, 1985. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=63286.
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Mamba, Phiwokuhle Bongisile. "Bioactivity of selected medicinal plants used for the treatment of sexually transmitted diseases." Diss., University of Pretoria, 2017. http://hdl.handle.net/2263/60834.
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Background: Sexually transmitted diseases (STD's) have a major impact on sexual and reproductive health worldwide. Each year, the World Health Organization (WHO) estimates 448 million new cases of curable STD's are diagnosed. The emergence of drug resistance in STD related microorganisms and potential side effects demand the discovery of newer drugs. The exploration of newer anti-microbial substances from natural sources may serve as promising alternatives. In this study, twelve medicinal plant species used traditionally in the treatment of STD's are investigated in this regard.
Methods: Ethanol plant extracts and three flavonoids were evaluated for their antimicrobial properties against one fungi and three bacteria, through the micro-dilution assay. To determine the anti-inflammatory activities of the extracts and compounds, the inhibitory effect was measured on the pro-inflammatory enzyme lipoxygenase, 15-LOX. Extracts were further evaluated for their inhibitory effect on the supercoiling activity of bacterial DNA gyrase by using the DNA gyrase kit. The extracts and compounds were lastly investigated for their anti-HIV activities against recombinant HIV-1 enzyme using non-radioactive HIV-RT colorimetric assay.
Results: Acacia karroo and Rhoicissus tridentata extracts showed good antimicrobial activity with MIC values ranging between 0.4 and 3.1 mg/ml. Extracts of Jasminum fluminense, Solanum tomentosum and flavonoid 2 and 3 had good anti-inflammatory activity with IC50 less than the positive control quercetin (IC50 = 48.86 ug/ml). Extracts of Diospyros mespiliformis, Peltophorum africanum, Rhoicissus tridentata and flavonoids 1 and 2 showed the best inhibitory activity against the bacterial DNA gyrase. A. karroo and flavonoid 3 exhibited moderate HIV RT inhibition activity of 66.8 and 63.7 % respectively. R. tridentata and Terminalia sericea had the best RT inhibition activity (75.7 and 100 %) compared to the positive control doxorubicin (96.5%) at 100 ug/ml concentration.
Conclusion: The observed activities may lead to new multi-target drugs against sexually transmitted diseases.Dissertation (MSc)--University of Pretoria, 2017.
Plant Science
MSc
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Bonfiglioli, Roderick. "Studies on the ultrastructural localisation of viroids and other plant pathogens." Title page, contents and summary only, 1997. http://web4.library.adelaide.edu.au/theses/09PH/09phb713.pdf.
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Bibliography: leaves 78-90. Designed to localize viroids at the histological and subcellular level and to determine with which cellular compartments the different viroids are associated. The majority of the work, in both the viroid and the phytoplasma studies involved the development of different methods and techniques.
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Van, Dyk Kerien. "Fungi associated with root and crown rot of wheat and barley in Tanzania." Diss., University of Pretoria, 2003. http://hdl.handle.net/2263/25941.
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Truter, Mariette. "Etiology and alternative control of potato rhizoctoniasis in South Africa." Pretoria : [s.n.], 2005. http://upetd.up.ac.za/thesis/available/etd-04122005-112047.
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Herrmann, Revital. "Characterization and efficacy testing of novel antifungal peptides in transgenic rice." Access to citation, abstract and download form provided by ProQuest Information and Learning Company; downloadable PDF file 2.08 Mb., 254 p, 2006. http://gateway.proquest.com/openurl?url_ver=Z39.88-2004&res_dat=xri:pqdiss&rft_val_fmt=info:ofi/fmt:kev:mtx:dissertation&rft_dat=xri:pqdiss:3220793.
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Waters, Brian M. "Iron nutrition in plants and yeast : studies on the FRO1 gene of Pisum sativum and the FET4 gene of Sacharomyces [sic] cerevisiae /." free to MU campus, to others for purchase, 2002. http://wwwlib.umi.com/cr/mo/fullcit?p3060158.
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Stone, Bethany. "The effects of boron deficiency and aluminum toxicity on plant magnesium /." free to MU campus, to others for purchase, 2001. http://wwwlib.umi.com/cr/mo/fullcit?p3036861.
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Schuh, Casey Steven. "Revisiting Management Practices for Diseases of Spring Barley in North Dakota." Thesis, North Dakota State University, 2018. https://hdl.handle.net/10365/28723.
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Common barley diseases observed in North Dakota include net blotch, spot blotch, leaf and stripe rust, bacterial leaf streak, and Fusarium head blight. The first objective of this research was to determine the effect of variety and fungicide timing on disease development of barley under conventionally tilled systems. Five field trials were performed in 2016-2017 to test the effect of common varieties and fungicide applications on foliar disease of barley. Overall, varietal selection had a greater effect on the level of foliar disease observed than fungicide application. The second objective focused on the efficacy and timing of adepidyn and prothioconazole + tebuconazole on Fusarium head blight. An inoculated greenhouse experiment was performed the fall of 2017 to determine the effectiveness of fungicide timing at half-spike, full-spike, and five days after full-spike. The protectant capabilities of the fungicides were greater than their curative properties.