Search PubMed⌕ Search

SEARCH · Search PubMed

Results for “common wheat”

Search indexed PubMed citations on genomics, clinical trials, systematic reviews and public health. Explore titles, authors and supplied subject terms, then open the PubMed record.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 217 records · Page 12Linked to original sources
PubMed2002

[Advances in studies of genome-specific repetitive DNA sequences in wheat and related species].

In this paper we review recent advances in studies of several aspects of genome specific repetitive DNA sequences in wheat and related species. The available results demonstrate that genome specific repetitive DNA sequences are important components of genome specificity in wheat and related species. Research on genome specific repetitive DNA sequences is essential to the elucidation of genome function. The application of genome specific repetitive DNA sequences will aid molecular cytogenetic studies in wheat and related species and contributes to genetic improvement of common wheat.

English Abstract↗
PubMed2005

Cloning of resistance gene analogs located on the alien chromosome in an addition line of wheat-Thinopyrum intermedium.

Homology-based gene/gene-analog cloning method has been extensively applied in isolation of RGAs (resistance gene analogs) in various plant species. However, serious interference of sequences on homoeologous chromosomes in polyploidy species usually occurred when cloning RGAs in a specific chromosome. In this research, the techniques of chromosome microdissection combined with homology-based cloning were used to clone RGAs from a specific chromosome of Wheat-Thinopyrum alien addition line TAi-27, which was derived from common wheat and Thinopyrum intermedium with a pair of chromosomes from Th. intermedium. The alien chromosomes carry genes for resistance to BYDV. The alien chromosome in TAi-27 was isolated by a glass needle and digested with proteinase K. The DNA of the alien chromosome was amplified by two rounds of Sau3A linker adaptor-mediated PCR. RGAs were amplified by PCR with the degenerated primers designed based on conserved domains of published resistance genes (R genes) by using the alien chromosome DNA, genomic DNA and cDNA of Th. intermedium, TAi-27 and 3B-2 (a parent of TAi-27) as templates. A total of seven RGAs were obtained and sequenced. Of which, a constitutively expressed single-copy NBS-LRR type RGA ACR 3 was amplified from the dissected alien chromosome of TAi-27, TcDR 2 and TcDR 3 were from cDNA of Th. intermedium, AcDR 3 was from cDNA of TAi-27, FcDR 2 was from cDNA of 3B-2, AR 2 was from genomic DNA of TAi-27 and TR 2 was from genomic DNA of Th. intermedium. Sequence homology analyses showed that the above RGAs were highly homologous with known resistance genes or resistance gene analogs and belonged to NBS-LRR type of R genes. ACR 3 was recovered by PCR from genomic DNA and cDNA of Th. intermedium and TAi-27, but not from 3B-2. Southern hybridization using the digested genomic DNA of Th. intermedium, TAi-27 and 3B-2 as the template and ACR 3 as the probe showed that there is only one copy of ACR 3 in the genome of Th. intermedium and TAi-27, but it is absent in 3B-2. The ACR 3 could be used as a specific probe of the R gene on the alien chromosome of TAi-27. Results of Northern hybridization suggested that ACR 3 was constitutively expressed in Th. intermedium and TAi-27, but not 3B-2, and expressed higher in leaves than in roots. This research demonstrated a new way to clone RGAs located on a specific chromosome. The information reported here should be useful to understand the resistance mechanism of, and to clone resistant genes from, the alien chromosome in TAi-27.

Amino Acid Sequence↗
PubMed2005

Heteroplasmy and paternally oriented shift of the organellar DNA composition in barley-wheat hybrids during backcrosses with wheat parents.

Mitochondrial (mt) and chloroplast (ct) genome inheritance was studied in barley-wheat hybrids, as were their progenies obtained from backcrosses with different common wheat cultivars, by monitoring the composition of 4 mtDNA (coxI, a 5'-flanking region of cob, nad3-orf156, and 5'-upstream region of 18S/5S) and 2 ctDNA (simple-sequence repeat locus downstream of trnS and a 3'-flanking region of rbcL) loci. In male sterile F1 and BC1 plants, maternal barley mtDNA fragments were mainly detected and very low levels of paternal wheat fragments were occasionally detected by PCR in coxI, a 5'-flanking region of cob and nad3-orf156, whereas a 5'-upstream region of 18S/5S showed clear heteroplasmy, containing both maternal and paternal copies, with maternal copies prevailing. Plants showing such heteroplasmic mtDNA composition remained either semisterile or became completely sterile in the later backcross generations. Only maternal ctDNA copies were detected in these plants. In 3 stable, self-fertile, and vigourous lines obtained in the advanced backcross generations and possessing recombinant wheat nuclear genome, however, only mt- and ctDNA copies of wheat parents were detected; thus, the original alloplasmic condition appeared to be lost. Our results suggest that transmission followed by selective replication of the paternal wheat organellar DNA leads to a paternally oriented shift of the organellar DNA composition in barley-wheat hybrids, which correlates with the restoration of fertility and plant vigour. These 2 processes seem to be related to nucleocytoplasmic compatibility and to be under the control of the nuclear genome composition.

Chimera↗
PubMed2006

Physical mapping of the blue-grained gene(s) from Thinopyrum ponticum by GISH and FISH in a set of translocation lines with different seed colors in wheat.

The original blue-grained wheat, Blue 58, was a substitution line derived from hybridization between common wheat (Triticum aestivum L., 2n=6x=42, ABD) and tall wheatgrass (Thinopyrum ponticum Liu & Wang=Agropyron elongatum, 2n=10x=70, StStEeEbEx), in which one pair of 4D chromosomes was replaced by a pair of alien 4Ag chromosomes (unknown group 4 chromosome from A. ponticum). Blue aleurone might be a useful cytological marker in chromosome engineering and wheat breeding. Cytogenetic analysis showed that blue aleurone was controlled by chromosome 4Ag. GISH analysis proved that the 4Ag was a recombination chromosome; its centromeric and pericentromeric regions were from an E-genome chromosome, but the distal regions of its two arms were from an St-genome chromosome. On its short arm, there was a major pAs1 hybridization band, which was very close to the centromere. GISH and FISH analysis in a set of translocation lines with different seed colors revealed that the gene(s) controlling the blue pigment was located on the long arm of 4Ag. It was physically mapped to the 0.71-0.80 regions (distance measured from the centromere of 4Ag). The blue color is a consequence of dosage of this small chromosome region derived from the St genome. We speculate that the blue-grained gene(s) could activate the anthocyanin biosynthetic pathway of wheat.

Chromosomes, Plant↗
PubMed2005

[The effect of phKL gene on homoeologous pairing of wheat-alien hybrids is situated between gene mutants of Ph1 and Ph2].

In natural populations of common wheat landrace, there has a phKL gene promoting homoeologous pairing of wheat-alien hybrids. In this study, the effects were compared among phKL, ph1b, ph2a and ph2b on homoeologous pairing of wheat-alien hybrids. The effects were indicated as ph1b > phKL > ph2b > ph2a, i. e. phKL gene was situated between gene mutants of Ph1 and Ph2.

Chromosome Pairing↗
PubMed2005

Mapping quantitative trait loci controlling agronomic traits in the spring wheat cross RL4452x'AC Domain'.

Relatively little is known about the genetic control of agronomic traits in common wheat (Triticum aestivum L.) compared with traits that follow Mendelian segregation patterns. A doubled-haploid population was generated from the cross RL4452x'AC Domain' to study the inheritance of the agronomic traits: plant height, time to maturity, lodging, grain yield, test weight, and 1000-grain weight. This cross includes the genetics of 2 western Canadian wheat marketing classes. Composite interval mapping was conducted with a microsatellite linkage map, incorporating 369 loci, and phenotypic data from multiple Manitoba environments. The plant height quantitative trait loci (QTLs), QHt.crc-4B and QHt.crc-4D, mapped to the expected locations of Rht-B1 and Rht-D1. These QTLs were responsible for most of the variation in plant height and were associated with other agronomic traits. An additional 25 agronomic QTLs were detected in the RL4452x'AC Domain' population beyond those associated with QHt.crc-4B and QHt.crc-4D. 'AC Domain' contributed 4 alleles for early maturity, including a major time to maturity QTL on 7D. RL4452 contributed 2 major alleles for increased grain yield at QYld.crc-2B and QYld.crc-4A, which are potential targets for marker-assisted selection. A key test weight QTL was detected on 3B and prominent 1000-grain weight QTLs were identified on 3D and 4A.

Chromosome Mapping↗
PubMed2003

Fusarium head blight resistance in hexaploid wheat (Triticum aestivum)-Lophopyrum genetic lines and tagging of the alien chromatin by PCR markers.

The objective of this research was to identify Fusarium head blight (FHB) resistance in wheat ( Triticum aestivum)- Lophopyrum genetic lines that might complement FHB resistance in common wheat; and to identify DNA markers that can be used to tag the resistance gene in the alien chromatin (E or el(2) genome) for the development of improved wheat cultivars. FHB resistance was evaluated in 19 Chinese Spring- Lophopyrum elongatum (EE) substitution lines, two Thatcher -L. ponticum (el(1) and el(2)) substitution lines, and four Thatcher- L. ponticum translocation lines. Significant resistance was identified in the substitution lines 7E(7A), 7E(7B), and 7E(7D). The homoeologous chromosome, 7el(2),()also showed resistance in the Thatcher genetic background. Both the Thatcher-7el(1) substitution and translocation lines were susceptible, like Thatcher, indicating that there is no resistance gene on the 7el(1) chromosome. Simple sequence repeat (SSR) and cleaved amplified polymorphic sequences (CAPS) in homoeologous group 7 chromosomes were used to identify DNA markers located on 7E and 7el(2). As expected, the transferability of wheat SSR markers to Lophopyrum is low. Of the 52 SSR markers that we tested, only five were found to be co-dominant on 7E of L. elongatum versus 7A, 7B, and 7D, one of which is also positive on 7el(2). A CAPS marker, derived from the RFLP probe PSR129, can serve as a dominant marker for 7el(2) chromatin.

Fusarium↗
PubMedDate not supplied

[The effect of natural selection on the allelic frequency of gliadin-coding loci and their associations in an artificially created hybrid population of winter wheat].

Hybrid population with heterogeneity for five gliadin-coding loci was created by crossing of five winter common wheat cultivars (Belozerskaya 47, Ilyichevka, Kyyanka, Mironovskaya 808, Polesskaya 70) by the complete scheme. Frequencies of alleles at these loci and their associations were analyzed after two, four and ten years of resowing. The ratio of alleles at the studied loci was changed as reproduction occurred. Gli 1A5 allele displayed stable tendency to frequency increasing, Gli 1D1--a little tendency and Gli 6A3--very essential tendency. The share of Gli 6D2 allele increased only after ten years of population reproduction. Combination of alleles at two, three, and five loci was not accidental. The most common regularity was predominance of the frequency of allelic associations characteristic of the parents (except for Ilyichevka) over new combinations. Possible causes of this phenomenon are discussed.

Alleles↗
PubMed2000

Development of an efficient maintenance and screening system for large-insert genomic DNA libraries of hexaploid wheat in a transformation-competent artificial chromosome (TAC) vector.

Three large-insert genomic DNA libraries of common wheat, Triticum aestivum cv. Chinese Spring, were constructed in a newly developed transformation-competent artificial chromosome (TAC) vector, pYLTAC17, which accepts and maintains large genomic DNA fragments stably in both Escherichia coli and Agrobacterium tumefaciens. The vector contains the cis sequence required for Agrobacterium-mediated gene transfer into grasses. The average insert sizes of the three genomic libraries were approximately 46, 65 and 120 kbp, covering three haploid genome equivalents. Genomic libraries were stored as frozen cultures in a 96-well format, each well containing approximately 300-600 colonies (12 plates for small library, four for medium-size library and four for large library). In each of the libraries, approximately 80% of the colonies harbored genomic DNA inserts of >50 kbp. TAC clones containing gene(s) of interest were identified by the pooled PCR technique. Once the target TAC clones were isolated, they could be immediately transferred into grass genomes with the Agrobacterium system. Five clones containing the thionin type I genes (single copy per genome), corresponding to each of the three genomes (A, B and D), were successfully selected by the pooled PCR method, in addition to an STS marker (aWG464; single copy per genome) and CAB (a multigene family). TAC libraries constructed as described here can be used to isolate genomic clones containing target genes, and to carry out genome walking for positional cloning.

Base Sequence↗
PubMed2001

The effects of chromosomes 3A and 3B on resistance to Fusarium head blight in tetraploid wheat.

Fusarium head blight (FHB) caused by Fusarium graminearum is one of the most destructive diseases of wheat in areas where the weather is warm and humid after heading. Previous studies indicate that the level of resistance to FHB varies not only among wheat cultivars but also among some of their wild relatives. No accession, however, has yet been identified to be completely immune to FHB among the Gramineae. It is known that durum wheat (Triticum turgidum L. conv. durum) is consistently more susceptible to FHB than common wheat (T. aestivum L.). The importance of the D genome in conferring resistance to FHB has been emphasized. Meanwhile, recent studies using molecular markers report effective QTLs on chromosome 3BS in a hexaploid population and on 3A in tetraploid recombinant inbred chromosome lines. In this study, we performed an evaluation of the effects of homoeologous group 3 chromosomes of T. turgidum ssp. dicoccoides on resistance to FHB using a set of chromosome substitution lines of a durum wheat cultivar 'Langdon'. The accession of T. turgidum ssp. dicoccoides examined in this study was more susceptible for Type II resistance (resistance to spread of FHB in the head) than 'Langdon'. Both of the chromosome substitution lines of 3A and 3B showed the same level of resistance with 'Langdon', but bleaching of the heads was completely prevented in the substitution lines of chromosome 3A without relationship to rachis fragility. It was concluded that the chromosome 3A of T. turgidum ssp. dicoccoides carries resistance gene(s) to head bleaching caused by FHB.

Chromosomes↗
PubMed1989

Effects of supplemental silage on forage intake and utilization by steers grazing wheat pasture or bermudagrass.

Seven trials were conducted to determine the effects of increasing amounts of silage (corn, wheat or sorghum) on forage intake, gastrointestinal tract fill, fecal output and ruminal flow and degradation of forage by cattle grazing wheat pasture or bermudagrass. In each of 3 yr, 24 steers grazed a common wheat or bermudagrass pasture and were randomly allocated to four treatments (0, .35, .70 or 1.05 kg silage DM.100 kg body weight-1.d-1). Intake and ruminal flow of forage were measured by feeding a single pulse dose of Yb-labeled forage followed by collection of fecal samples for 4 to 5 d and fitting Yb concentrations to a one-compartment, age-dependent model. Ruminal digestion kinetics of wheat forage were estimated in situ using eight ruminally cannulated steers fed 0 or .55 kg sorghum silage DM.100 kg body weight-1.d-1. Supplemental silage decreased wheat forage (P less than .10) and bermudagrass (P less than .01) intake linearly. However, total forage intake of bermudagrass plus silage increased linearly (P less than .05). Each kilogram of added silage DM decreased DM intake of wheat forage by .66 +/- .25 and of bermudagrass by .63 +/- .17 kg. Flow and turnover of wheat forage or bermudagrass were not altered (P greater than .15) by supplemental silage. Silage consumption increased extent of ruminal degradation of wheat forage DM (P less than .05; 63.1 vs 52.5%), indicating a positive associative effect of silage on wheat forage utilization.(ABSTRACT TRUNCATED AT 250 WORDS)

Animal Feed↗
PubMed1997

Molecular structure of a wheat chromosome end healed after gametocidal gene-induced breakage.

In the progeny of the monosomic addition line of common wheat, Triticum aestivum, carrying the gametocidal chromosome of Aegilops cylindrica, deletion chromosomes carrying the break point within the nucleolar organizing region of chromosome 1B appeared. Attempts were made to amplify the break points by PCR using primers of telomere and rDNA (rRNA gene). In one deletion line, specific amplification of DNA fragments including the 18S rRNA gene, telomere repeats, and their junction occurred. At the junction of telomere and rRNA gene there was a 31-bp inverted duplication of the rRNA gene. Telomere sequences were initiated from the sequence TAG in the duplication. Between the duplications a small sequence was also inserted. This novel DNA sequence at the break point indicates that the breakage-fusion-bridge cycle(s) took place after the first chromatin breakage by the gametocidal gene.

Base Sequence↗
PubMed2005

Expression profile of two storage-protein gene families in hexaploid wheat revealed by large-scale analysis of expressed sequence tags.

To discern expression patterns of individual storage-protein genes in hexaploid wheat (Triticum aestivum cv Chinese Spring), we analyzed comprehensive expressed sequence tags (ESTs) of common wheat using a bioinformatics technique. The gene families for alpha/beta-gliadins and low molecular-weight glutenin subunit were selected from the EST database. The alignment of these genes enabled us to trace the single nucleotide polymorphism sites among both genes. The combinations of single nucleotide polymorphisms allowed us to assign haplotypes into their homoeologous chromosomes by allele-specific PCR. Phylogenetic analysis of these genes showed that both storage-protein gene families rapidly diverged after differentiation of the three genomes (A, B, and D). Expression patterns of these genes were estimated based on the frequencies of ESTs. The storage-protein genes were expressed only during seed development stages. The alpha/beta-gliadin genes exhibited two distinct expression patterns during the course of seed maturation: early expression and late expression. Although the early expression genes among the alpha/beta-gliadin and low molecular-weight glutenin subunit genes showed similar expression patterns, and both genes from the D genome were preferentially expressed rather than those from the A or B genome, substantial expression of two early expression genes from the A genome was observed. The phylogenetic relationships of the genes and their expression patterns were not correlated. These lines of evidence suggest that expression of the two storage-protein genes is independently regulated, and that the alpha/beta-gliadin genes possess novel regulation systems in addition to the prolamin box.

Base Sequence↗
PubMed2003

[Efficient production of wheat alien translocation lines and characterization by molecular cytogenetics].

The Triticum aestivum-Leymus mollis and T. aestivum-Thinopyrum intermedium translocation lines were induced by gametocidal chromosome 3C derived from Aegilops triuncialis and gamma-ray irradiated pollens of a T. aestivum-Th. intermedium addition line TAI-14 with a lower dosage (10Gy), respectively. By genomic in situ hybridization (GISH) analysis, three T. aestivum-L. mollis translocation lines (WM-10, WM-43 and WM-47) and three deletion lines (WM-18, WM-43 and WM-44) were selected from 59 F2 plants derived from a cross combination of T. aestivum-L. mollis substitution line M8724-8-13 x T. aestivum-Ae. triunicalis 3C chromosome addition line. The frequency of translocation lines produced and total frequency of chromosome structural variation occurred were 5.08% and 8.47%, respectively. Two of the three translocation lines, WM-10 and WM-43 all were heterozygous translocation lines carrying one T. aestivum-L. mollis Robertsonian translocation chromosome, but the translocation chromosome in the two lines were different in morphology. The other one, WM-47 was a double heterozygous translocation with two different translocation chromosomes. By the C-banding, one of the three translocation lines was identified, the translocation chromosome consisted of 7DL of wheat and a chromosome arm of L. mollis. In addition, wheat chromosome deletions were observed in some plants. In another cross combination involved in common wheat and T. aestivum-Th. intermedium addition line, two alien terminal non-Robertsonian translocation lines (WI-21 and WI-68) were identified from 69 F2 plants by C-banding and GISH, and the percentage of translocation line was 2.90%. By C-banding analysis, the translocation chromosomes involved in wheat chromosomes 3A and 4A in the two lines, respectively. These results indicate that inducing wheat alien translocation line by gametocidal chromosome and irradiated pollens all are efficient methods.

Chromosome Banding↗
PubMed2003

Correlated clustering and virtual display of gene expression patterns in the wheat life cycle by large-scale statistical analyses of expressed sequence tags.

Compared to rice, wheat exhibits characteristic growth habits and contains complex genome constituents. To assess global changes in gene expression patterns in the wheat life cycle, we conducted large-scale analysis of expressed sequence tags (ESTs) in common wheat. Ten wheat tissues were used to construct cDNA libraries: crown and root from 14-day-old seedlings; spikelet from early and late flowering stages; spike at the booting stage, heading date and flowering date; pistil at the heading date; and seeds at 10 and 30 days post-anthesis. Several thousand colonies were randomly selected from each of these 10 cDNA libraries and sequenced from both 5' and 3' ends. Consequently, a total of 116 232 sequences were accumulated and classified into 25 971 contigs based on sequence homology. By computing abundantly expressed ESTs, correlated expression patterns of genes across the tissues were identified. Furthermore, relationships of gene expression profiles among the 10 wheat tissues were inferred from global gene expression patterns. Genes with similar functions were grouped with one another by clustering gene expression profiles. This technique might enable estimation of the functions of anonymous genes. Multidimensional analysis of EST data that is analogous to the microarray experiments may offer new approaches to functional genomics of plants.

Contig Mapping↗
PubMed2006

Hydrolysed wheat proteins present in cosmetics can induce immediate hypersensitivities.

Cosmetics containing hydrolysed wheat proteins (HWP) can induce rare but severe allergic reactions. 9 patients, all females without common wheat allergy, but with contact urticaria to such cosmetics, were studied. 6 of them also experienced generalized urticaria or anaphylaxis to foods containing HWP. All patients had low to moderate levels of immunoglobulin (Ig)E specific of wheat flour (f4) or gluten (f79). Their sensitivity to HWP and their tolerance to unmodified wheat proteins extracted from grains were confirmed using skin tests. Immunoblotting analyses showed that IgE from all patients reacted with almost all HWP tested. Reactions generally occurred with large random peptide aggregates. IgE reacted also with unmodified grain proteins, which contrasted with skin tests results. They reacted always with salt soluble proteins but variably with gluten proteins. No reaction occurred with gliadins in patients without associated immediate hypersensitivity to food containing HWP. These results show the role of hydrolysis on the allergenicity of wheat proteins, both through skin or digestive routes. At least part of the epitopes involved is pre-existing in unmodified wheat proteins. The aggregation of peptide bearing these epitopes and others created by hydrolysis, along with the increased solubility and the route of exposure, are possible factors of the allergenicity of HWP.

Adult↗
PubMed2000

[Analysis of genetic diversity of wheat using genetic resources information system GRIS].

The possibilities of using the Genetic Resources Information and Analysis System (GRIS) 3.2, a database and software package, in studies of various aspects of genetic diversity in wheat are demonstrated. A model of genetic diversity was analyzed; diversity levels were estimated in wheat from various regions at different times. The genetic basis of Russian winter and spring common wheat cultivars was investigated. Transmission of powdery mildew resistance genes was traced in cultivars with identified Pm genes. For some genes, patterns of geographical distribution were characterized. Description of GRIS 3.2 is given: the package consists of a database on the global gene pool of wheat and software on genealogical and statistic analyses of genetic diversity.

Databases, Factual↗
PubMed2006

Molecular tagging of stripe rust resistance gene YrZH84 in Chinese wheat line Zhou 8425B.

Stripe rust, caused by Puccinia striiformis f. sp. tritici (PST), is one of the most damaging diseases in common wheat (Triticum aestivum L.). With the objective of identifying and tagging new genes for resistance to stripe rust, F1, F2 and F3 populations from the cross Zhou 8425B/Chinese Spring were inoculated with Chinese PST isolate CYR32 in the greenhouse. A total of 790 SSR primers were used to test the parents and resistant and susceptible bulks. The resulting seven polymorphic markers on chromosome 7BL were used for genotyping F2 and F3 populations. Results indicated that Zhou 8425B carries a single dominant resistance gene, temporarily designated YrZH84, closely linked to SSR markers Xcfa2040-7B and Xbarc32-7B with genetic distances of 1.4 and 4.8 cM, respectively. In a seedling test with 25 PST isolates, the reaction patterns of YrZH84 were different from those of lines carrying Yr2 and Yr6. It was concluded that YrZH84 is probably a new stripe rust resistance gene.

Cloning, Molecular↗