Spelling suggestions: "subject:"ester yellow"" "subject:"ester yellowstone""
1 |
Some aspects of the transmission of the virus of aster yellows.Weinstein, Leonard H. 01 January 1950 (has links) (PDF)
No description available.
|
2 |
Management of the aster leafhopper and aster yellows in WisconsinJensen, John Ove. January 1982 (has links)
Thesis (Ph. D.)--University of Wisconsin--Madison, 1982. / Typescript. Vita. eContent provider-neutral record in process. Description based on print version record. Includes bibliographical references (leaves 182-203).
|
3 |
Diversity of aster yellows phytoplasmas in lettuceZhang, Jianhua. January 2003 (has links)
Thesis (Ph. D.)--Ohio State University, 2003. / Title from OhioLINK abstract page. Abstract.
|
4 |
Insect transmitted plant pathogenic mollicutes, Spiroplasma kunkelii and aster yellows witches' broom phytoplasma from structural genomics to functional genomics /Bai, Xiaodong, January 2004 (has links)
Thesis (Ph. D.)--Ohio State University, 2004. / Title from first page of PDF file. Document formatted into pages; contains xvii, 232 p.; also includes graphics (some col.). Includes bibliographical references (p. 206-232).
|
5 |
Studies on migration and control of the six-spotted leafhopper Macrosteles fascifrons (Stål) in relation to transmission of aster-yellows virusChiykowski, L. N. January 1958 (has links)
Thesis (Ph. D.)--University of Wisconsin--Madison, 1958. / Typescript. Vita. eContent provider-neutral record in process. Description based on print version record. Includes bibliographical references (leaves 121-126).
|
6 |
Molecular and Biochemical Genetic Studies on Some Leafhopper transmitted Plant PathogensElateek, Sawsan Y. 01 November 2010 (has links)
No description available.
|
7 |
Identificação molecular de um fitoplasma do grupo 16Srl-B em plantas de soja / Molecular identification of a group 16SrI-B phytoplasma in soybean plantsPereira, Thays Benites Camargo 19 January 2012 (has links)
Plantas apresentando folhas com deformações do tipo bolhas, menor quantidade de vagens de tamanho reduzido e contendo menor número de sementes, vagens que não completaram a maturação e coloração verde da parte aérea no final do ciclo foram observadas em campos de produção. As plantas foram analisadas visando à detecção de fitoplasmas e a sua identificação molecular. Para isto, o DNA total das plantas amostradas foi submetido ao teste de duplo PCR conduzido com primers específicos para a região do 16S rDNA de fitoplasmas. As amplificações evidenciaram que fitoplasmas estavam presentes em tecidos de plantas sintomáticas. O duplo PCR realizado com primers grupo-específicos revelou a ocorrência de fitoplasmas afiliados aos grupos 16SrI e 16SrIII. As análises virtuais de RFLP, baseadas no sequenciamento da referida região genômica, permitiram identificar um dos fitoplasmas como pertencente ao subgrupo 16SrI-B. Os valores de coeficientes de similaridade, calculados com base nos padrões de restrição gerados in silico por 17 enzimas, confirmaram a identidade deste fitoplasma. Ainda, mapas de restrição mostraram que o fitoplasma encontrado em plantas de soja apresentava sítios putativos de restrição idênticos a um fitoplasma típico do grupo 16SrI-B. A análise filogenética, envolvendo o fitoplasma alvo deste estudo e fitoplasmas representantes de alguns grupos e subgrupos relatados no Brasil, mostrou que o fitoplasma da soja estava estritamente relacionado com aqueles componentes do grupo 16SrI. O fitoplasma em estudo emergiu do mesmo ramo da árvore filogenética também compartilhado por fitoplasmas do grupo 16SrI, confirmando os resultados dos demais testes moleculares. Os resultados gerados neste trabalho evidenciaram que a soja pode ser considerada como mais um hospedeiro de fitoplasmas pertencentes aos grupos 16SrI e 16SrIII, os quais tem sido relatados em associação com diversas doenças de plantas que ocorrem no Brasil. Este estudo também gera informações que podem contribuir para aumentar os conhecimentos sobre este emergente grupo de agentes causais de doença. / Plants exhibiting leaf deformation type bubbles, low quantities of pods of reduced size containing few seeds, pods not mature, and green color of stem and leaves in the end of crop growth were observed in commercial fields. The plants were tested for the detection of phytoplasmas and their molecular identification. For this, the total DNA of plants sampled was submitted to nested PCR assays conducted with universal primers for amplification of a fragment corresponding to the 16S rDNA of phytoplasmas. The amplifications revealed the presence of phytoplasmas in tissues of symptomatic plants. For identification, nested PCR performed with group-specific primers demonstrated the occurrence of phytoplasmas affiliated to the groups 16SrI and 16SrIII. The virtual RFLP analysis, based on the sequencing of DNA fragments generated from nested PCR with universal primers, allowed the identification of a phytoplasma belonging to the subgroup 16SrI-B. The values of similarity coefficients, calculated on the basis of restriction patterns generated in silico for 17 enzymes, confirmed the identity of this phytoplasma. Furthermore, restriction maps showed that the phytoplasma found in soybean plants had putative restriction sites identical to those phytoplasma of the group 16SI-B. Phylogenetic analysis, involving the phytoplasma identified in the present study and representatives of some groups and subgroups previously reported in Brazil, showed that the soybean phytoplasma was closely related to phytoplasmas belonging to group 16SrI. The studied phytoplasma and phytoplasmas belonging to group 16SrI emerged from the same branch, confirming the results obtained by PCR and RFLP analysis. Also, based on the results, soybean could be considered as a host for phytoplasmas belonging to the group 16SrI and 16SrIII, which has been reported in association with various diseases that occur in Brazil. The present study may contribute to improve the knowledge about this emerging group of causal agents of disease.
|
8 |
Some studies on the aster-yellows virus and transmission by the six-spotted leafhopper Macrosteles fascifrons (Stål.)Lee, Peter Elliot, January 1961 (has links)
Thesis (Ph. D.)--University of Wisconsin--Madison, 1961. / Typescript. Vita. eContent provider-neutral record in process. Description based on print version record. Includes bibliographical references (leaves 84-87).
|
9 |
Strains of aster-yellows virus and their transmission by the six-spotted leafhopper, Macrosteles fascifrons (Stal)Granados, Robert R. January 1965 (has links)
Thesis (Ph. D.)--University of Wisconsin, 1965. / Typescript. Vita. eContent provider-neutral record in process. Description based on print version record.
|
10 |
The determination of the spatial and temporal distribution of Aster Yellows phytoplasma in grapevineSmyth, Natalie 04 1900 (has links)
Thesis (MSc)--Stellenbosch University, 2015. / ENGLISH ABSTRACT: South Africa is ranked amongst the top ten for wine production internationally. Viticulture
contributes immensely to the economy, which justifies research into the pathogens that may
negatively affect wine production. Aster Yellows phytoplasma was reported in South African
vineyards in 2010 and has since been an ongoing problem for grape farmers in affected areas.
Throughout the world, phytoplasma diseases such as Grapevine Yellows have caused
detrimental effects on the vines, often resulting in death. The limited knowledge on
prevention and control of the pathogen can be attributed to the lack of full understanding of
the epidemiology and accurate diagnosis.
The aim of this study was to determine the spatial distribution of Aster Yellows phytoplasma
in individual grapevines and to record a possible temporal or seasonal distribution. The
recovery phenotype phenomenon was encountered during the study and surveys were
conducted in order to determine whether recovery was permanent. In order to perform the
studies, a reliable assay to accurately detect the pathogen in grapevines was required.
A comparison between three assays was completed in furtherance of deciding which to use
for the further experimentation. The three assays included a nested PCR utilizing universal
primers, a Real-Time PCR using Syto9 as a double stranded DNA specific dye and a Real-
Time PCR with a TaqMan® probe using an identical dilution series. Of the three assays
tested, the nested PCR proved to be the most sensitive diagnostic procedure, detecting Aster
Yellows phytoplasma in very low titers and was thus used for diagnostics in further
experiments. In order to determine the spatial patterns of Aster yellows phytoplasma
infection, leaf, petiole, trunk, root and cane samples were taken from three whole grapevine
plants. Phloem scrapings obtained from the cane samples yielded more positive results in
comparison to the other parts of the plant tested. Not only do phytoplasmas display an erratic
spatial distribution, but also have a tendency to change over time. Thirty symptomatic
grapevines were sampled over one and a half growing seasons, with results concluding that
February yielded the most positive diagnoses. Fifty plants that had been previously pruned
back and no longer displayed symptoms were also sampled in 2013 and 2014, and all yielded
negative results over both years. This study contributes to comprehension of Aster Yellows
phytoplasma epidemiology and ultimately the advancement of accurate diagnosis. / AFRIKAANSE OPSOMMING: Suid-Afrika is internasionaal geposisioneer onder die top tien vir die produksie van wyn.
Wingerd dra geweldig by tot die ekonomie, wat navorsing oor die patogene wat
wynporduksie negatief beïnvloed, regverdig. Aster Yellows phytoplasmais in 2010
gerapporteer in Suid-Afrikaanse wingerde en is sedertdien 'n deurlopende probleem vir
druiweboere in geaffekteerde gebiede. Dwarsdeur die wêreld, het fitoplasma siektes soos
Grapevine Yellows ‘n nadelige uitwerking op wingerde, wat dikwels lei tot plantsterftes. Die
beperkte kennis oor die voorkoming en beheer van die patogeen kan toegeskryf word aan die
gebrek aan begrip van die epidemiologie en akkurate diagnose .
Die doel van hierdie studie was om die ruimtelike verspreiding van Aster geel fitoplasma in
individuele wingerdstokke te bepaal en 'n moontlike tydelike of seisoenale verspreiding aan
te teken. Die herstel-fenotipe verskynsel is tydens die studie teëgekom en opnames is
uitgevoer ten einde te bepaal of die herstel permanent was. Ten einde die studie uit te voer , is
'n betroubare toets vereis om die patogeen in wingerde akkuraat te spoor.
: Drie toetse is vergelyk (en geëvalueer) vir hulle geskikthed vir gebruik in die studie. Die
drie toetse het ingesluit 'n geneste PKR wat gebruik maak van universele primers, 'n in-tydse
PKR (real-time PCR) wat Syto9 gebruik as 'n dubbelstring DNS spesifieke kleurstof, en 'n
in-tydse PKR met 'n TaqMan® peiler, en is vergelyk met behulp van 'n identiese vedunnings
reeks. Van die drie toetse , is die geneste PCR bewys om die mees sensitiewe diagnostiese
prosedure te wees , en kon Aster geel fitoplasma in baie lae titers opspoor en is dus gebruik
vir die diagnose in verdere eksperimente. Ten einde die ruimtelike patrone van Aster geel
fitoplasma infeksie te bepaal, is blaar, blaarsteel, stam, wortel en loot monsters van drie volle
wingerdstokke geneem. Floëem skraapsels verkry uit die loot monsters het meer positiewe
resultate opgelewer in vergelyking met die ander dele van die plant. Nie net vertoon
phytoplasmas 'n wisselvallige ruimtelike verspreiding nie, maar het ook 'n neiging om te
verander met verloop van tyd. Dertig simptomaties wingerdstokke is versamel oor een en 'n
half groeiseisoene,en die resultate het gewys dat Februarie die meeste positiewe diagnoses
het. Monsters is versamel in 2013 en 2014 van vyftig plante wat voorheen teruggesnoei is en
nie meer simptome vertoon nie, en alle monsters het negatiewe resultate opgelewer oor beide
jare. Hierdie studie dra by tot begrip van Aster geel fitoplasma epidemiologie en uiteindelik
die bevordering van akkurate diagnose.
|
Page generated in 0.0656 seconds