Show simple item record

dc.contributor.advisorHine, Richard B.en_US
dc.contributor.authorABDUL SATTAR, MUSTAFA HASSAN.
dc.creatorABDUL SATTAR, MUSTAFA HASSAN.en_US
dc.date.accessioned2011-10-31T17:51:18Z
dc.date.available2011-10-31T17:51:18Z
dc.date.issued1983en_US
dc.identifier.urihttp://hdl.handle.net/10150/185881
dc.description.abstractDeclining infestations and the cyclic appearance of Phymatotrichum root rot of cotton from season to season led to the suggestion that antagonistic microorganisms were the cause of this phenomenon. This study was concerned primarily with Actinomycetes spp., fluorescent Pseudomonads, Trichoderma spp., and other fungi. There was a continuous fluctuation in the population of Actinomycetes spp. and fluorescent Pseudomonads on the surface of strands. Populations of these antagonistic organisms dropped as the viability of strands of P. omnivorum decline. Comparison of the rhizoplane microflora from infected and healthy roots showed no relationship between the populations of Actinomycetes spp. and fluorescent Pseudomonads and the resistance of healthy roots to invasion by P. omnivorum. Similarly, soil samples collected from areas with declining infestations and assayed for populations of Actinomycetes spp. and fluorescent Pseudomonads, revealed no differences in the populations of these antagonistic organisms. This indicates that the absence of the disease in areas with declining infestations is not due to the microorganisms investigated in this study. Higher mortality rates of strands of P. omnivorum occurred when strands were exposed to Actinomycetes spp. and fluorescent Pseudomonads or to their metabolites. The hyphal deformation observed on strands from the field could not be reproduced in vitro. The same antagonistic microorganisms sprayed on cotton roots containing strands failed to reduce strand viability.
dc.language.isoenen_US
dc.publisherThe University of Arizona.en_US
dc.rightsCopyright © is held by the author. Digital access to this material is made possible by the University Libraries, University of Arizona. Further transmission, reproduction or presentation (such as public display or performance) of protected items is prohibited except with permission of the author.en_US
dc.subjectCotton root rot.en_US
dc.subjectSoil microbiology -- Arizona -- Marana Region.en_US
dc.titleFACTORS AFFECTING VIABILITY OF STRANDS OF PHYMATOTRICHUM OMNIVORUM (SHEAR) DUGGAR.en_US
dc.typetexten_US
dc.typeDissertation-Reproduction (electronic)en_US
dc.identifier.oclc688635458en_US
thesis.degree.grantorUniversity of Arizonaen_US
thesis.degree.leveldoctoralen_US
dc.contributor.committeememberStanghellini, M. E.en_US
dc.contributor.committeememberGilbertson, R. L.en_US
dc.contributor.committeememberMisaghi, I. J.en_US
dc.contributor.committeememberMcClure, M. A.en_US
dc.identifier.proquest8315269en_US
thesis.degree.disciplinePlant Pathologyen_US
thesis.degree.disciplineGraduate Collegeen_US
thesis.degree.namePh.D.en_US
refterms.dateFOA2018-04-26T14:36:05Z
html.description.abstractDeclining infestations and the cyclic appearance of Phymatotrichum root rot of cotton from season to season led to the suggestion that antagonistic microorganisms were the cause of this phenomenon. This study was concerned primarily with Actinomycetes spp., fluorescent Pseudomonads, Trichoderma spp., and other fungi. There was a continuous fluctuation in the population of Actinomycetes spp. and fluorescent Pseudomonads on the surface of strands. Populations of these antagonistic organisms dropped as the viability of strands of P. omnivorum decline. Comparison of the rhizoplane microflora from infected and healthy roots showed no relationship between the populations of Actinomycetes spp. and fluorescent Pseudomonads and the resistance of healthy roots to invasion by P. omnivorum. Similarly, soil samples collected from areas with declining infestations and assayed for populations of Actinomycetes spp. and fluorescent Pseudomonads, revealed no differences in the populations of these antagonistic organisms. This indicates that the absence of the disease in areas with declining infestations is not due to the microorganisms investigated in this study. Higher mortality rates of strands of P. omnivorum occurred when strands were exposed to Actinomycetes spp. and fluorescent Pseudomonads or to their metabolites. The hyphal deformation observed on strands from the field could not be reproduced in vitro. The same antagonistic microorganisms sprayed on cotton roots containing strands failed to reduce strand viability.


Files in this item

Thumbnail
Name:
azu_td_8315269_sip1_m.pdf
Size:
1.849Mb
Format:
PDF
Description:
azu_td_8315269_sip1_m.pdf

This item appears in the following Collection(s)

Show simple item record