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Association Analysis and Genome-wide Selection for Early Maturity in WheatMheni, Nafeti Titus January 2014 (has links)
No description available.
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Development of hard white winter wheats for a hard red winter wheat regionUpadhyay, Madhusudan P. January 1984 (has links)
Call number: LD2668 .T4 1984 U62 / Master of Science
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Rate and duration of spikelet initiation, their inheritance and relationships to yield components in wheatLu, Debin. January 1985 (has links)
Call number: LD2668 .T4 1985 L82 / Master of Science
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Tagging and mapping of prominent structural genes on chromosome arm 7DL of common wheatGroenewald, Johannes Zacharias 12 1900 (has links)
Thesis (PhD (Agric)) -- Stellenbosch University, 2001. / ENGLISH ABSTRACT: Chromosome arm 7DL of common wheat carries genes for agronomically important traits such
as leaf rust, stem rust, Russian wheat aphid and eye spot resistance. Some of these genes occur
on introgressed foreign chromatin, which restricts their utility in breeding. The 7DL genetic
maps are poorly resolved, which seriously hampers attempts to manipulate the genes and
introgressed regions in breeding. This dissertation represents an attempt to improve our
knowledge of the relative map positions of three resistance genes that have significant potential
for use in local breeding programmes.
The leaf rust resistance gene, Lr19, is located on a Thinopyrum ponticum-derived translocation
which occupies a large part of the terminal end of 7DL. The translocation also carries genes for
less favourable traits such as yellow flour colour. Attempts have been made to reduce the size of
the translocation through allosyndetic pairing induction; the primary aims being to remove
deleterious genes and to minimise the amount of foreign chromatin associated with Lr19 so it can
be recombined with other useful 7DL genes. Twenty-nine 'Indis'-derived Lr 19 deletion mutants
were previously produced by gamma irradiation and a physical map was constructed. In this
study, the set of mutant lines were further analysed using 144 Sse8387I/Msei and 32 EcoRI/Msel
amplified fragment length polymorphism (AFLP) primer combinations. The previous physical
map, which was based on five restriction fragment length polymorphism (RFLP) markers and five
structural gene loci, was extended and now includes 95 novel AFLP markers (86 Sse8387I/Msei
and 9EcoRI!Msel markers), of which seven map close to Lr 19. Most of the deletions could be
ordered according to size and the improved map has already been used to characterise shortened
recombinant forms of the Lr 19 translocation. An unsuccessful attempt was made to convert one
of the seven markers closest to Lr 19 into a sequence-specific marker. However, an AFLP
marker located distally from Lr 19 was successfully converted into a sequence-specific marker in
collaboration with other researchers.
An attempt was also made to map and tag the Russian wheat aphid (RWA) resistance gene, Dn5.
A doubled haploid mapping population consisting of 94 lines was created and typed for Dn5,
four microsatellite loci and the endopeptidase locus, Ep-Dl. The Dn5 locus mapped 25.4 cM
and 28.6 cM distally from Xg.vm111 and Xg.vm437, respectively, but was not linked to Xgwm428, Xgwm3 7 or Ep-Dl. Tagging of Dn5 was attempted by screening twelve homozygous
resistant and seven homozygous susceptible F2 lines from a cross between 'Chinese Spring' and
'PI 294994' with 70 Sse8387IIi\1sei AFLP primer combinations. Only two potentially useful
polymorphisms (one in coupling and one in repulsion phase) were identified. Conversion of the
coupling phase marker to a sequence-specific marker was not successful.
The eyespot resistance gene, Pchl , was derived from Triticum ventricosum and is present in the
wheat VPM-1. Close association between Pchl and the endopeptidase Ep-Dlb allele has been
reported previously. Pchl/Ep-Dl was tagged by screening ten wheat genotypes (each
homozygous for the confirmed presence or absence of Pchl and/or Ep-Dl b) with 36
Sse83 87I/ Msei AFLP primer combinations. Three AFLP markers were closely associated with
Pchl I Ep-D 1, one of which was targeted for conversion into a sequence-specific marker. The
sequence-specific marker contained a microsatellite core motif and was found to be useful for
tagging Pchl!Ep-Dl. A genetic distance of 2 cM was calculated between the novel
microsatellite marker and Ep-Dl. The microsatellite marker was also polymorphic for the Lr 19
translocation and it was possible to map it between the Wsp-Dl and Sr25 loci.
In this dissertation, mapping and/or tagging of three important resistance genes were achieved.
Due to the fact that all markers used in these studies were not polymorphic between all of the
targeted regions, it was not possible to fully integrate the data obtained for the three regions. / AFRIKAANSE OPSOMMING: Chromosoom arm 7DL van broodkoring dra gene vir agronomies-belangrike kenrnerke soos
blaarroes, stamroes, Russiese koringluis en oogvlek weerstand. Sommige van hierdie gene kom
voor in blokke spesie-verhaalde chromatien wat hul bruikbaarheid in teling beperk. Die
genetiese kaarte van 7DL is swak ontwikkel en dit maak dit baie moeilik om hierdie gene en
spesie-verhaalde streke tydens teling te manipuleer. Hierdie proefskrif verteenwoordig 'n paging
om kennis van die relatiewe kaart liggings van drie weerstandsgene, met betekenisvolle
potensiaal in plaaslike tee! programme, te verbreed.
Die blaarroes weerstandsgeen, Lr 19, kom voor op 'n Thinopyrum ponticum-verhaalde
translokasie wat 'n groot terminale gedeelte van 7DL beslaan. Die translokasie dra ook gene vir
minder gewensde kenrnerke soos gee! meelkleur. Pogings is aangewend om die translokasie
deur homoeoloe parings-induksie te verkort. Die doe! was om nadelige gene te verplaas en die
hoeveelheid vreemde chromatien geassosieer met Lr 19 te minimiseer sodat dit met ander nuttige
gene op 7DL gerekombineer kan word. Nege-en-twintig 'Indis'-verhaalde Lr 19 delesie mutante
is vroeer met gamma bestraling geproduseer en gebruik om 'n fisiese kaart op te stel.
Teenswoordig is die stel mutante verder ontleed met behulp van 144 Sse8387I!Msei en 32
EcoRII Msel amplifikasie-fragment-lengte-polimorfisme (AFLP) inleier kombinasies. Die
bestaande fisiese kaart, wat gebaseer was op vyf restriksie-fragment-lengte-polimorfisme
(RFLP) merkers en vyf strukturele geen loki, is uitgebrei en sluit nou 95 unieke AFLP merkers
(86 Sse8387I/Msel en 9EcoRI/Msel merkers) in, waarvan sewe naby aan Lr19 karteer. Die
meeste van die delesies kon op grond van hulle grootte gegroepeer word en die verbeterde
fisiese kaart is alreeds gebruik om verkorte rekombinante vorms van die Lr 19 translokasie te
karakteriseer. 'n Onsuksesvolle paging is aangewend om een van die sewe merkers naaste aan
Lr 19 om te skakel na 'n volgorde-spesifieke merker. 'n AFLP merker wat distaal van Lr 19
karteer is egter wel suksesvol in samewerking met ander navorsers omgeskakel na 'n volgordespesifieke
merker.
'n Paging is ook aangewend om die Russiese koringluis (RKL) weerstandsgeen, Dn5, te karteer
en merkers gekoppel aan die geen te identifiseer. 'n Verdubbelde-haplo!ede karteringspopulasie
van 94 lyne is geskep en getipeer vir Dn5, vier mikrosatelliet loki en die endopeptidase lokus,
Ep-D1. Die Dn5 lokus karteer 25.4 cM en 28.6 cM distaal van Xgwml11 en Xgwm437, respektiewelik, maar was me gekoppel met Xgwm428, Xgwm37 of Ep-D1 me. Twaalf
homosigoties weerstandbiedende en sewe homosigoties vatbare F2 lyne uit die kruising:
'Chinese Spring' I 'PI 294994' is met 70 Sse8387VMsel AFLP inleier kombinasies getoets in 'n
poging om merkers vir Dn5 te identifiseer. Slegs twee moontlik bruikbare polimorfismes (een
in koppelings- en een in repulsie fase ), is ge'identifiseer. Omskakeling van die koppelingsfase
merker na 'n volgorde-spesifieke merker was onsuksesvol.
Die oogvlek weerstandsgeen, Pch1, is uit Triticum ventricosum oorgedra en kom voor in die
koringlyn, VPM-1. Noue koppeling van Pch1 en die endopeptidase alleel, Ep-D1 b, is vantevore
gerapporteer. Merkers is vir P chl I Ep-D 1 gevind deur tien koring genoti pes ( elkeen
homosigoties vir die bevestigde teenwoordigheid of afwesigheid van Pch1 en/of Ep-D1 b) te
toets met 36 Sse83871/kfsel AFLP inleier kombinasies. Drie AFLP merkers is gevind wat nou
koppel met Pchl!Ep-D1 , waarvan een gekies is vir omskakeling na 'n volgorde-spesifieke
merker. Die volgorde-spesifieke merker het 'n mikrosatelliet kernmotief bevat en was nuttig as
merker vir Pch1/Ep-D1. 'n Genetiese afstand van 2 cM is tussen die unieke mikrosatelliet
merker en Ep-D1 bereken. Die mikrosatelliet merker was ook polimorfies vir die Lr 19
translokasie en dit is tussen die Wsp-D1 en Sr25 loki gekarteer.
Kartering en/of identifikasie van merkers vir drie belangrike weerstandsgene was suksesvol in
hierdie studie. Omdat al die merkers wat gebruik is, nie polimorf was tussen al die streke van
belang nie, was dit nie moontlik om die data vir elk van die drie streke ten volle te integreer nie.
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Genetic and molecular analysis of resistance to rust diseases in barleyGolegaonkar, Prashant G January 2007 (has links)
Doctor of Philosophy / The responses of 92 barley genotypes to selected P. hordei pathotypes was assessed in greenhouse tests at seedling growth stages and in the field at adult plant growth stages to determine known or unknown resistances. On the basis of multipathotype tests, 35 genotypes were postulated to carry Rph2, Rph4, Rph5, Rph12, RphCantala alone or combinations of Rph2 + Rph4 and Rph1 + Rph2, whereas 52 genotypes lacked detectable seedling resistance to P. hordei. Five genotypes carried seedling resistance that was effective to all pathotypes tested, of which four were believed to carry uncharacterised resistance based on pedigree information. Field tests at adult plant growth stages indicated that while 28 genotypes were susceptible, 57 carried uncharacterised APR to P. hordei. Pedigree analysis indicated that APR in the test genotypes could have been derived from three different sources. The resistant responses of seven cultivars at adult plant growth stages were believed to be due to the presence of seedling resistance effective against the field pathotypes. Genetic studies conducted on 10 barley genotypes suggested that ‘Vada’, ‘Nagrad’, ‘Gilbert’, ‘Ulandra (NT)’ and ‘WI3407’ each carry one gene providing adult plant resistance to P. hordei. Genotypes ‘Patty’, ‘Pompadour’ ‘Athos’, ‘Dash’ and ‘RAH1995’ showed digenic inheritance of APR at one field site and monogenic inheritance at a second. One of the genes identified in each of these cultivars provided high levels of APR and was effective at both field sites. The second APR gene was effective only at one field site, and it conferred low levels of APR. Tests of allelism between resistant genotypes confirmed a common APR gene in all genotypes with the exception of ‘WI3407’, which based on pedigree information was genetically distinct from the gene common in ‘Vada’, ‘Nagrad’, ‘Patty’, ‘RAH1995’ and ‘Pompadour’. An incompletely dominant gene, Rph14, identified previously in an accession of Hordeum vulgare confers resistance to all known pathotypes of P. hordei in Australia. The inheritance of Rph14 was confirmed using 146 and 106 F3 lines derived from the crosses ‘Baudin’/ ‘PI 584760’ (Rph14) and ‘Ricardo’/‘PI 584760’ (Rph14), respectively. Bulk segregant analysis on DNA from the parental genotypes and resistant and susceptible DNA bulks from F3 lines using diversity array technology (DArT) markers located Rph14 to the short arm of chromosome 2H. Polymerase chain reaction (PCR) based marker analysis identified a single simple sequence repeat (SSR) marker, Bmag692, linked closely to Rph14 at a map distance of 2.1 and 3.8 cM in the populations ‘Baudin’/ ‘PI 584760’and ‘Ricardo’/‘PI 584760’, respectively. Seedlings of 62 Australian and two exotic barley cultivars were assessed for resistance to a variant of Puccinia striiformis, referred to as BGYR, which causes stripe rust on several wild Hordeum species and some genotypes of cultivated barley. With the exception of six Australian barley cultivars and an exotic cultivar, all displayed resistance to the pathogen. Genetic analyses of six Australian barley cultivars and the Algerian barley ‘Sahara 3771’, suggested that they carried either one or two major seedling resistance genes to the pathogen. A single recessive seedling resistance gene, Bgyr1, identified in ‘Sahara 3771’ was located on the long arm of chromosome 7H and flanked by restriction fragment length polymorphism (RFLP) markers wg420 and cdo347 at genetic distances of 12.8 and 21.9 cM, respectively. Mapping resistance to BGYR at adult plant growth stages using a doubled haploid population derived from the cross ‘Clipper’/‘Sahara 3771’ identified two major QTLs on the long arms of chromosomes 3H and 7H that explained 26 and 18% of total phenotypic variation, respectively. The QTL located on chromosome 7HL corresponded to the seedling resistance gene Bgyr1. The second QTL was concluded to correspond to a single adult plant resistance gene designated Bgyr2, originating from cultivar ‘Clipper’.
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Comparative study of genes for resistance to bunt (Tilletia caries (D.C.) Tul. and T. foetida (Wallr.) Liro) of wheat ; Cytological investigations in PhalarisAmbastha, Harendra Narayan Sinha. January 1953 (has links) (PDF)
Typewritten copy Comparative study of genes for resistance to bunt (Tilletia caries (D.C.) Tul. and T. foetida (Wallr.) Liro); Cytological investigations in Phalaris called part 2.
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Manganese efficiency in durum wheat (Triticum targidum L. var durum) / by Hossein Khabaz Saberi.Saberi, Hossein Khabaz January 1999 (has links)
Bibliography: leaves 203-212. / xiii, 212 leaves : ill. ; 30 cm. / Title page, contents and abstract only. The complete thesis in print form is available from the University Library. / This study investigated the genetic diversity for tolerance of durum wheat (Triticum turgidum L. var durum) to micronutrient deficient soils with an emphasis on manganese. 69 genotypes were studied under field conditions at Marion Bay (Lower Eyre Peninsula) and Coonalpyn. Durum genotypes, notably Stojocri, were identified as having higher tolerance than commerical durum varieties. / Thesis (Ph.D.)--University of Adelaide, Dept. of Plant Science, 1999
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Genetics of boron tolerance in durum wheatJamjod, Sansanee. January 1996 (has links) (PDF)
Bibliography: leaves 234-256. Genetic studies of tolerance of durum wheat (Triticum turgidum L. var durum) to high concentrations of boron (B) were undertaken to identify genetic variation in response to B, the mode of gene action, number of genes and chromosomal locations of genes controlling tolerance. Results demonstrated that tolerance to B is under simple genetic control as observed in bread wheat. High levels of tolerance can be transferred into sensitive commercial varieties via backcrossing and selection can be performed during seedling growth at early generations.
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Manganese efficiency in durum wheat (Triticum targidum L. var durum)Saberi, Hossein Khabaz. January 1999 (has links) (PDF)
Bibliography: leaves 203-212. This study investigated the genetic diversity for tolerance of durum wheat (Triticum turgidum L. var durum) to micronutrient deficient soils with an emphasis on manganese. 69 genotypes were studied under field conditions at Marion Bay (Lower Eyre Peninsula) and Coonalpyn. Durum genotypes, notably Stojocri, were identified as having higher tolerance than commerical durum varieties.
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Phosphorylation of plant translation initiation factors by CK2Dennis, Michael Don, 1980- 29 August 2008 (has links)
Protein kinase CK2 phosphorylates wheat eIF2, eIF3, eIF4B, eIF5 and three 60S ribosomal proteins. The substrate specificity of CK2[alpha] toward various plant initiation factor substrates was altered in vitro through holoenzyme formation in the presence of regulatory [beta]-subunits. This presents a potential mechanism through which the differential expression and sub-cellular distribution of CK2 [beta]-subunits could regulate phosphorylation of various CK2 substrates in plants. Our analysis of initiation factor phosphopeptides produced by in vitro phosphorylation identified 20 CK2 phosphorylation sites in eIF2[alpha], eIF2[beta], eIF3c, eIF4B, and eIF5. Native wheat eIF5 was prepared in the presence of phosphatase inhibitors and analyzed by mass spectrometry. Native wheat eIF5 was determined to be a phosphoprotein containing at least 3 phosphorylation sites. The C-terminal CK2 site (S451) of native eIF5 was completely phosphorylated, and tryptic fragments containing the other in vitro CK2 two sites (S209, T240) also appear to be partially phosphorylated. Many of the CK2 phosphorylation sites identified are in conserved binding domains of the yeast multifactor complex (eIF1/eIF3/eIF5/eIF2/GTP/Met-tRNAi[superscript Met). This observation lead to the hypothesis that CK2 phosphorylation may regulate the formation of plant multifactor complexes. The results presented here suggest that plant initiation factors are capable of forming complexes similar to those previously reported in yeast. The in vitro interaction of initiation factors within these complexes appears to be enhanced by phosphorylation of eIF2, eIF3c, and eIF5 by CK2. Site-directed mutagenesis of eIF5 to remove CK2 phosphorylation sites not only prevents the CK2 mediated increase in interaction with eIF1, but also resulted in reduced stimulation of translation initiation in vitro. / text
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