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dc.contributor.authorStobbs, Lorne W.en_US
dc.date.accessioned2009-10-02T13:19:53Z
dc.date.available2009-10-02T13:19:53Z
dc.date.issued1975-10-02T13:19:53Z
dc.identifier.urihttp://hdl.handle.net/10464/2741
dc.description.abstractSTOBBS, Lorne,W ABSTRACT Biochemical and Histological Investigations of viral localisation in the hypersensitive reaction of Phaseolus vulgaris L. var Pinto to tobacco mosaic virus infection. The infection of Phaseolus vulgaris L. var Pinto with tobacco mosaic virus (TMV) results in the production of distinct necrotic lesions confining the virus to restricted areas of the leaf surface. Biochemical and histological changes in the leaf tissue as a result of infection have been described. Trace accumulations of fluorescent metabolites, detected prior to lesion expression represent metabolites produced, by the cell in response to virus infection. These substances, are considered to undergo oxidation and in diffusing into adjacent cells, react with cellular constituents causing the death of these cells. Such cellular necrosis in advance of infection effectively limits virus spread. Chromatographic studies on extracts from TMV infected Pinto bean leaf tissue suggests that a number of extra-fluorescent metabolites produced on lesion'expression represent end products of phenolic oxidation r,eactionsoccurring earlier in these cells. Inhibition of phenolic oxidation by ascorbate infiltration or elevated temperature treatment resulted in the absence of extra-fluorescent metabolites and the continued movement of virus in the absence of necrosis. Further studies with i ascorbate infiltration indicated that irreversible necrotic events were determined as early as 12 tci 18 hrs after viral inoculation. Histochemical tests indicated that callose formation was initiated at this time, and occurred in response to necrotisation. Inhibition of necrosis by either ascorbate infiltration or elevated temp8rature treatment resulted in the absence of callose deposition. Scanning electron'micrographs of infected tissue revealed severe epidermal and palisade cell damage. Histochemical tests indicated extensive callose formation in cells bordering the lesion, and suggested the role of callose iTh the blockage of intercellular connections limiting virus movement. The significance of these cellular changes is discussed. iien_US
dc.language.isoengen_US
dc.publisherBrock Universityen_US
dc.subjectTobacco mosaic virus.en_US
dc.subjectVirology--Research.en_US
dc.titleBiochemical and histological investigations of viral localisation in the hypersensitive reaction of Phaselous vulgaris L. var Pinto to tobacco mosaic virus infectionen_US
dc.typeElectronic Thesis or Dissertationen_US
dc.degree.nameM.Sc. Biological Sciencesen_US
dc.degree.levelMastersen_US
dc.contributor.departmentDepartment of Biological Sciencesen_US
dc.degree.disciplineFaculty of Mathematics and Scienceen_US


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