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dc.contributor.advisorLabuschagne, M. T.
dc.contributor.advisorViljoen, C. D.
dc.contributor.authorKoen, Elizma
dc.date.accessioned2015-10-29T08:54:58Z
dc.date.available2015-10-29T08:54:58Z
dc.date.copyright2006-06
dc.date.issued2006-06
dc.date.submitted2006-06
dc.identifier.urihttp://hdl.handle.net/11660/1491
dc.description.abstractEnglish: Ethiopian cultivars and advanced lines of bread and durum wheat were studied for their grain quality characteristics under different environmental conditions. The influence of different protein fractions, ratios and subunits on bread making quality were determined by means of HPLC. Significant correlations across diverse genotypes and environments might indicate the potential use of these techniques in breeding programmes. SE-HPLC Bread wheat · The genotypes studied expressed genetic variability in most of the important quality traits. Protein levels across the two environments were relatively low. A decrease in protein content led to an increase in mixing time. Genotypes at the lowest protein site had the longest mixing times. · The higher protein site had higher average concentrations for all fractions extracted, except for SDS soluble and insoluble LMP. · Across the two environments, the SDS soluble and insoluble polymeric proteins had a highly significant influence on quality. · The number of correlations observed increased across environments compared to individual environments. · Higher significant correlations were observed between ratios of proteins compared to that found between individual proteins. SE-HPLC Durum · Similar results to bread wheat were seen for durum genotypes tested. The lower protein environment resulted in a lower protein content and increased mixing time. · The average concentrations for SDS soluble LPP and SMP and insoluble LMP, SMP, TUPP and LUPP were higher at the high protein potential site. · The number of correlations increased across environments, than when environments were considered individually. · The magnitude of the correlations increased across environments. · Higher significant correlations were observed between ratios of protein fractions and quality traits, notably the correlations between the ratio of SDS insoluble LPP:LMP and SPP:LMP with mixograph development time (0.545*** and 0.518***, respectively). · Durum has the potential of improvement for bread making quality. Bread and durum wheat · The average flour protein content was slightly higher for durum wheat, at the higher protein site, but similar at Motta. · The mixograph development time for both wheat types was longer at Motta, than at Adet, with the mixing time for durum slightly longer than that of bread wheat at Motta. · The durum genotypes had higher average SDS soluble and insoluble LPP and SMP fractions, at both environments, compared to bread wheat. · The opposite was true for LUPP and TUPP fractions, where the bread wheat genotypes had a higher average. · The LUPP fraction and the SDS insoluble SPP displayed a direct relationship with SDS sedimentation, continuously across environments. · The averages of baking quality traits for bread and durum wheat, with the exception of SDS sedimentation, did not differ extensively. This indicated the potential application of durum wheat for comparable breadmaking utility. RP-HPLC Due to the large amount of data generated by RP-HPLC, emphasis was placed on the general trends across entries and differences between entries were not discussed. Bread wheat · A total of 38 glutenin subunits (including minor peaks and unresolved shouders) were resolved. · Forty two bread wheat gliadin peaks were differentiated. · The environmental effect was visible in entries in both variation in quantity observed and as presence or absence of subunits. · Peaks/subunits correlating with baking parameters differed across different environments. This indicated sensitivity to environmental influences. · Some correlations occurred consistently, regardless of the differences in environment. · Significant polymeric-polymeric and monomeric-monomeric as well as polymeric-monomeric correlations were observed. These interactions need to be considered when determining functionality. Correlations might be due to indirect effects. · Stepwise multiple regression can assist in determining direct relationships. It also gives an indication of the interactions excisting between protein components. · The regression models indicated the individual proteins contributing to the quality trait. Some proteins were major contibutors, explaining 59% of the variation occurring in the parameter. The most important contributors to quality remained the glutenin subunits. Durum wheat · A total of 42 glutenin subunits (including minor peaks and unresolved shouders) were resolved. · Fifty one durum wheat gliadin peaks were differentiated. · Similar results to bread wheat were obtained for durum wheat entries. · Unlike the bread wheat results, specific durum subunits influenced more than one baking parameter simultaneously. · More interactions between the different protein subunits influencing specific traits were visible. No distinct patterns were visible between the subunit type and functional property.en_ZA
dc.description.abstractAfrikaans: Etiopiese brood en durum koring kultivars en gevorderde lyne is in verskillende omgewingstoestande vir kwaliteitseienskappe bestudeer. Die invloed van verskillende proteïenfraksies, -verhoudings en subeenhede op broodbak-kwaliteit is m.b.v.. HPLC ontleed. Betekenisvolle korrelasies tussen en binne diverse omgewings en genotipes kan die moontlike gebruik van die tegniek in teelprogramme aandui. SE-HPLC Broodkoring • Genotipes wat vir die studie gebruik is, het variasie in meeste van die belangrike kwaliteitskenmerke getoon. Die proteïen-inhoud in beide omgewings was relatief laag. Die lae proteïen-inhoud het die mengtyd verkort. Genotipes wat in die lae proteïen-potensiaal omgewing geplant is, het die langste mengtyd getoon. • Die hoër proteïen-potensiaal omgewing het die hoogste gemiddelde konsentrasie vir al die proteïenfraksies wat bestudeer is, getoon, buiten vir SDS-oplosbare en onoplosbare groot monomeriese proteïene. • Die SDS oplosbare en onoplosbare proteïene het ‘n hoogs betekenisvolle invloed op die bakkwaliteit, oor beide omgewings, uitgeoefen. • ‘n Groter aantal korrelasies tussen proteïenfraksies en kwaliteit, oor beide omgewings as binne die verskillende omgewings, is waargeneem. • Hoër betekenisvolle korrelasies tussen die verskillende proteïenverhoudings en kwaliteit, as tussen kwaliteit en individuele proteïene, is waargeneem. SE-HPLC Durumkoring • Die waargenome resultate vir durum koring was soortgelyk aan brood koring. Die laer proteïen-potensiaal omgewing het tot ‘n laer proteïeninhoud en langer mengtye gelei. • Die hoër proteïen-potensiaal-omgewing het ook die hoogste gemiddelde SDS oplosbare groot polimeriese, klein monomeriese en onoplosbare LMP, SMP, TUPP en LUPP opgelewer. • ‘n Groter aantal korrelasies is oor die twee omgewings as binne die afsonderlike omgewings waargeneem. • Die waargenome korrelasies was hoër oor verskillende omgewings as binne omgewings. • Korrelasies tussen verskillende proteïen verhoudings en die bakkwaliteit was betekenisvol hoër as tussen die individuele proteïenfraksies, veral die verhoudings van SDS onoplosbare LPP:LMP en SPP:LMP met mengtye van 0.545*** en 0.518***, onderskeidelik. • Durum koring besit gevolglik die potensiaal om vir broodbak-kwaliteit verbeter te word. Brood- en durumkoring • Die gemiddelde meel proteïen-inhoud in die hoër proteïen potensiaalomgewing was effens hoër vir durumkoring, maar dieselfde by Motta. • Die miksogram-ontwikkelingstyd vir beide koring-soorte was langer by Motta as by Adet. Die mengtyd van durumkoring by Motta was effe langer in vergelyking met die van brood. • In vergelyking met die gemiddeldes van broodkoring, is hoër gemiddelde SDS oplosbare en onoplosbare LPP en SPP fraksies by beide omgewings vir durumgenotipes waargeneem. • Die teenoorgestelde is vir die gemiddelde LUPP en TUPP van broodkoring waargeneem. • ‘n Volgehoue verwantskap tussen LUPP en SDS onoplosbare SPP met SDS sedimentasie is oor beide omgewings waargeneem. • Die gemiddelde resultate van die bak-kwaliteitstoetse vir brood- en durumkoring, uitgesonderd SDS sedimentasie, het nie ‘n groot verskil getoon nie, wat daarop dui dat durumkoring wel die potensiaal het om brood van vergelykbare gehalte te produseer. RP-HPLC Aangesien die RP-HPLC tegniek groot hoeveelhede data genereer het, is ‘n volledige bespreking van die individuele inskrywings baie kompleks. In hierdie afdeling is daar dus op die algemene neigings en patrone wat waargeneem kan word, gefokus terwyl die individuele verskille binne die genotipes nie bespreek is nie. Brood koring • ‘n Totaal van 38 glutenien subeenhede (insluitende kleiner pieke en onvolledige skouers) is geïdentifiseer. • Twee-en-veertig gliadien pieke is onderskei. • Die omgewings-effek was sigbaar in die verskillende konsentrasies en teenwoordigheid of afwesigheid van sekere fragmente. • Verskillende korrelasies tussen pieke (subeenhede) en bak-eienskappe in verskillende omgewings is gevind, wat weereens op die omgewing se invloed gedui het. • Sommige korrelasies is, ongeag verskille in die omgewings, konstant waargeneem. • Betekenisvolle korrelasies is tussen polimeries-polimeries, monomeries-monomeries en polimeries-monomeriese fraksies waargeneem. Hierdie korrelasies moet in ag geneem word wanneer die funksionele aspek van proteïene bestudeer word. Korrelasies tussen kwaliteitstoetse en proteïene kan indirek ontstaan. • Stapsgewyse veelvuldige regressie-bepaling kan tot die bepaling van direkte verwantskappe bydra. Dit kan ook ‘n aanduiding wees van die interaksies wat tussen die verskillende proteïenkomponente bestaan. • Die regressie modelle dui die individuele bydrae van die verskillende proteïene tot kwaliteit aan. Die individuele bydrae van sommige proteïene was groter as ander, en kan tot 59% van die variasie wat voorkom, verklaar. Die gluteniene blyk steeds die belangrikste bydraers totkwaliteit te wees. Durum koring • Vir durumkoring is ‘n totaal van 42 glutenien subeenhede (kleiner pieke en onvolledige skouers) waargeneem. • Die gliadien gemiddeldes was bietjie meer, met 51 pieke. • Soortgelyke resultate as die van broodkoring is waargeneem. • Die grootste verskil tussen durum- en broodkoring was dat een proteïen meer as een kenmerk gelyktydig affekteer. • ‘n Groter aantal interaksies tussen spesifieke proteïene en kwaliteitseienskappe is waargeneem, maar geen spesifieke patroon kon tussen spesifieke groepe proteïene en die funksionele kenmerke van deeg herken word nie.af
dc.description.sponsorshipNational Research Foundation (NRF)en_ZA
dc.language.isoenen_ZA
dc.publisherUniversity of the Free Stateen_ZA
dc.subjectThesis (Ph.D. (Plant Sciences (Plant Breeding))--University of the Free State, 2006en_ZA
dc.subjectDurum wheat -- Qualityen_ZA
dc.subjectGlutenen_ZA
dc.subjectBreaden_ZA
dc.titleThe use of gluten proteins to predict bread and durum wheat qualityen_ZA
dc.typeThesisen_ZA
dc.rights.holderUniversity of the Free Stateen_ZA


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