Sample records for hexaploid wheat population

  1. Genetic Diversity and Population Structure Analysis of European Hexaploid Bread Wheat (Triticum aestivum L.)

    E-print Network

    Schierup, Mikkel Heide

    Genetic Diversity and Population Structure Analysis of European Hexaploid Bread Wheat (Triticum. Here, Diversity Array Technology (DArT) was used to characterize a population of 94 bread wheat polymorphic and could be used for population structure analysis. Two major subgroups of wheat varieties, Gr

  2. Genetic Variation of Seed Dormancy in Synthetic Hexaploid Wheat-Derived Populations

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Aegilops tauschii, the D-genome donor of wheat (Triticum aestivum), has very strong seed dormancy and genes controlling the trait may be used in breeding programs to manipulate germinability of improved cultivars. Thus, this research was conducted to initiate a project to identify dormancy genes fro...

  3. Genetic structure of Argentinean hexaploid wheat germplasm

    PubMed Central

    Vanzetti, Leonardo S.; Yerkovich, Nadia; Chialvo, Eugenia; Lombardo, Lucio; Vaschetto, Luis; Helguera, Marcelo

    2013-01-01

    The identification of genetically homogeneous groups of individuals is an ancient issue in population genetics and in the case of crops like wheat, it can be valuable information for breeding programs, genetic mapping and germplasm resources. In this work we determined the genetic structure of a set of 102 Argentinean bread wheat (Triticum aestivum L.) elite cultivars using 38 biochemical and molecular markers (functional, closely linked to genes and neutral ones) distributed throughout 18 wheat chromosomes. Genetic relationships among these lines were examined using model-based clustering methods. In the analysis three subpopulations were identified which correspond largely to the origin of the germplasm used by the main breeding programs in Argentina. PMID:24130447

  4. Virus-Induced Gene Silencing in Hexaploid Wheat

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Functional genomics analysis in hexaploid wheat is greatly impeded by the genetic redundancy of polyploidy and the difficulties in generating large numbers of transgenic plants required in insertional mutagenesis strategies. Virus-induced gene silencing (VIGS), however, is a strategy for creating g...

  5. Evolution of physiological responses to salt stress in hexaploid wheat.

    PubMed

    Yang, Chunwu; Zhao, Long; Zhang, Huakun; Yang, Zongze; Wang, Huan; Wen, Shanshan; Zhang, Chunyu; Rustgi, Sachin; von Wettstein, Diter; Liu, Bao

    2014-08-12

    Hexaploid bread wheat (Triticum aestivum L., genome BBAADD) is generally more salt tolerant than its tetraploid wheat progenitor (Triticum turgidum L.). However, little is known about the physiological basis of this trait or about the relative contributions of allohexaploidization and subsequent evolutionary genetic changes on the trait development. Here, we compared the salt tolerance of a synthetic allohexaploid wheat (neo-6x) with its tetraploid (T. turgidum; BBAA) and diploid (Aegilops tauschii; DD) parents, as well as a natural hexaploid bread wheat (nat-6x). We studied 92 morphophysiological traits and analyzed homeologous gene expression of a major salt-tolerance gene High-Affinity K(+) Transporter 1;5 (HKT1;5). We observed that under salt stress, neo-6x exhibited higher fitness than both of its parental genotypes due to inheritance of favorable traits like higher germination rate from the 4x parent and the stronger root Na(+) retention capacity from the 2x parent. Moreover, expression of the D-subgenome HKT1;5 homeolog, which is responsible for Na(+) removal from the xylem vessels, showed an immediate transcriptional reprogramming following allohexaploidization, i.e., from constitutive high basal expression in Ae. tauschii (2x) to salt-induced expression in neo-6x. This phenomenon was also witnessed in the nat-6x. An integrated analysis of 92 traits showed that, under salt-stress conditions, neo-6x resembled more closely the 2x than the 4x parent, suggesting that the salt stress induces enhanced expressivity of the D-subgenome homeologs in the synthetic hexaploid wheat. Collectively, the results suggest that condition-dependent functionalization of the subgenomes might have contributed to the wide-ranging adaptability of natural hexaploid wheat. PMID:25074914

  6. Gene networks in hexaploid wheat: interacting quantitative trait loci for grain protein content

    Microsoft Academic Search

    Pawan Kulwal; Neeraj Kumar; Ajay Kumar; Raj Kumar Gupta; Harindra Singh Balyan; Pushpendra Kumar Gupta

    2005-01-01

    In hexaploid wheat, single-locus and two-locus quantitative trait loci (QTL) analyses for grain protein content (GPC) were conducted using two different mapping populations (PI and PII). Main effect QTLs (M-QTLs), epistatic QTLs (E-QTLs) and QTL × environment interactions (QE, QQE) were detected using two-locus analyses in both the populations. Only a few QTLs were common in both the analyses, and

  7. A modified TILLING approach to detect induced mutations in tetraploid and hexaploid wheat

    PubMed Central

    Uauy, Cristobal; Paraiso, Francine; Colasuonno, Pasqualina; Tran, Robert K; Tsai, Helen; Berardi, Steve; Comai, Luca; Dubcovsky, Jorge

    2009-01-01

    Background Wheat (Triticum ssp.) is an important food source for humans in many regions around the world. However, the ability to understand and modify gene function for crop improvement is hindered by the lack of available genomic resources. TILLING is a powerful reverse genetics approach that combines chemical mutagenesis with a high-throughput screen for mutations. Wheat is specially well-suited for TILLING due to the high mutation densities tolerated by polyploids, which allow for very efficient screens. Despite this, few TILLING populations are currently available. In addition, current TILLING screening protocols require high-throughput genotyping platforms, limiting their use. Results We developed mutant populations of pasta and common wheat and organized them for TILLING. To simplify and decrease costs, we developed a non-denaturing polyacrylamide gel set-up that uses ethidium bromide to detect fragments generated by crude celery juice extract digestion of heteroduplexes. This detection method had similar sensitivity as traditional LI-COR screens, suggesting that it represents a valid alternative. We developed genome-specific primers to circumvent the presence of multiple homoeologous copies of our target genes. Each mutant library was characterized by TILLING multiple genes, revealing high mutation densities in both the hexaploid (~1/38 kb) and tetraploid (~1/51 kb) populations for 50% GC targets. These mutation frequencies predict that screening 1,536 lines for an effective target region of 1.3 kb with 50% GC content will result in ~52 hexaploid and ~39 tetraploid mutant alleles. This implies a high probability of obtaining knock-out alleles (P = 0.91 for hexaploid, P = 0.84 for tetraploid), in addition to multiple missense mutations. In total, we identified over 275 novel alleles in eleven targeted gene/genome combinations in hexaploid and tetraploid wheat and have validated the presence of a subset of them in our seed stock. Conclusion We have generated reverse genetics TILLING resources for pasta and bread wheat and achieved a high mutation density in both populations. We also developed a modified screening method that will lower barriers to adopt this promising technology. We hope that the use of this reverse genetics resource will enable more researchers to pursue wheat functional genomics and provide novel allelic diversity for wheat improvement. PMID:19712486

  8. Evaluation and haplotype analysis of elite synthetic hexaploid wheat lines for resistance to Hessian fly

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Synthetic hexaploid wheat (SHW), derived from tetraploid wheat ' Aegilops tauschii hybrid, is an excellent source of resistance genes for various diseases and insects in wheat. The objectives of this study were to evaluate the elite SHW lines developed at the International Maize and Wheat Improvemen...

  9. Synthetic hexaploids: Harnessing species of the primary gene pool for wheat improvement

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Incorporation of genetic diversity into elite wheat cultivars has long been recognized as a means of improving wheat productivity and securing the global wheat supply. Synthetic hexaploid wheat (SHW) recreated from its two progenitor species, the tetraploid, Triticum turgidum and its diploid wild r...

  10. Chromosomes form into seven groups in hexaploid and tetraploid wheat as a prelude to meiosis

    E-print Network

    Shaw, Peter

    Chromosomes form into seven groups in hexaploid and tetraploid wheat as a prelude to meiosis. The present study reveals that, as a prelude to meiosis, these 21 chromosome pairs in hexaploid (and. This results in the association of multiple chromosomes, which then need to be resolved as meiosis progresses

  11. Quality Characteristics of Waxy Hexaploid Wheat ( Triticum aestivum L.): Properties of Starch Gelatinization and Retrogradation

    Microsoft Academic Search

    Katsuyuki Hayakawa; Keiko Tanaka; Toshiki Nakamura; Shigeru Endo; Tsuguhiro Hoshino

    1997-01-01

    Cereal Chem. 74(5):576-580 The viscoelastic properties and molecular structure of the starch isolated from waxy (amylose-free) hexaploid wheat (WHW) (Triticum aestivum L.) were examined. WHW starch generally had lower gelatinization onset temperature, peak viscosity, and setback than the starch isolated from normal hexaploid wheat (NHW). Differential scanning calorimetry (DSC) showed that WHW starch had higher transition temperatures (To, Tp, and

  12. Registration of hard kernel puroindoline allele nearisogenic line hexaploid wheat genetic stocks.

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Seven puroindoline allele near-isogenic line (NIL) hexaploid wheat (Triticum aestivum L.) genetic stocks (GS-xxxx – GS-xxxx; PI 644080 – PI 644086) were developed by Dr. Craig F. Morris at the USDA-ARS Western Wheat Quality Laboratory, Pullman, Washington. As they incorporate the first seven known ...

  13. NOTICE OF RELEASE OF HARD KERNEL PUROINDOLINE ALLELE NEAR-ISOGENIC LINE HEXAPLOID WHEAT GENETIC STOCKS

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The Agricultural Research Service, U.S. Department of Agriculture announces the release of seven hard kernel puroindoline allele near-isogenic line (NIL) hexaploid wheat (Triticum aestivum L.) genetic stocks (PI xxxxxx – PI xxxxxx) developed by Dr. Craig F. Morris at the USDA-ARS Western Wheat Quali...

  14. Genetic association of OPR genes with resistance to Hessian fly in hexaploid wheat

    PubMed Central

    2013-01-01

    Background Hessian fly (Mayetiola destructor) is one of the most destructive pests of wheat. The genes encoding 12-oxo-phytodienoic acid reductase (OPR) and lipoxygenase (LOX) play critical roles in insect resistance pathways in higher plants, but little is known about genes controlling resistance to Hessian fly in wheat. Results In this study, 154 F6:8 recombinant inbred lines (RILs) generated from a cross between two cultivars, ‘Jagger’ and ‘2174’ of hexaploid wheat (2n?=?6?×?=42; AABBDD), were used to map genes associated with resistance to Hessian fly. Two QTLs were identified. The first one was a major QTL on chromosome 1A (QHf.osu-1A), which explained 70% of the total phenotypic variation. The resistant allele at this locus in cultivar 2174 could be orthologous to one or more of the previously mapped resistance genes (H9, H10, H11, H16, and H17) in tetraploid wheat. The second QTL was a minor QTL on chromosome 2A (QHf.osu-2A), which accounted for 18% of the total phenotypic variation. The resistant allele at this locus in 2174 is collinear to an Yr17-containing-fragment translocated from chromosome 2N of Triticum ventricosum (2n?=?4?×?=28; DDNN) in Jagger. Genetic mapping results showed that two OPR genes, TaOPR1-A and TaOPR2-A, were tightly associated with QHf.osu-1A and QHf.osu-2A, respectively. Another OPR gene and three LOX genes were mapped but not associated with Hessian fly resistance in the segregating population. Conclusions This study has located two major QTLs/genes in bread wheat that can be directly used in wheat breeding programs and has also provided insights for the genetic association and disassociation of Hessian fly resistance with OPR and LOX genes in wheat. PMID:23724909

  15. Stem rust, tan spot, Stagonospora nodorum blotch, and Hessian fly resistance in Langdon durum - Aegilops tauschii synethetic hexaploid wheat lines.

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Diseases and pests of wheat incur serious yield and quality losses to wheat grown worldwide. In the current study, we tested synthetic hexaploid wheat (SHW) lines developed from various Aegilops tauschii lines crossed with the tetraploid durum wheat line Langdon. The SHW lines were tested along wi...

  16. EVALUATION OF 10 CHEMICALS FOR ANEUPLOIDY INDUCTION IN THE HEXAPLOID WHEAT ASSAY

    EPA Science Inventory

    This study was a part of an international project sponsored by the Commission of the European Communities to evaluate the utility of the hexaploid wheat assay (Redei and Sandhu, 1988) to detect chemically induced aneuploidy. en known or suspect spindle poisons; i.e., colchicine (...

  17. Construction and characterization of a bacterial artificial chromosome library for hexaploid wheat line 92R137

    Technology Transfer Automated Retrieval System (TEKTRAN)

    For map-based cloning of genes conferring important traits in the hexaploid wheat line 92R137, a bacterial artificial chromosome (BAC) library, including two sub libraries, was constructed using the genomic DNA of 92R137 digested with restriction enzymes HindIII and BamHI. The BAC library was compos...

  18. Identification of quantitative trait loci for abscisic acid responsiveness in the D-genome of hexaploid wheat.

    PubMed

    Iehisa, Julio C M; Matsuura, Takakazu; Mori, Izumi C; Yokota, Hirokazu; Kobayashi, Fuminori; Takumi, Shigeo

    2014-06-15

    In crop species such as wheat, abiotic stresses and preharvest sprouting reduce grain yield and quality. The plant hormone abscisic acid (ABA) plays important roles in abiotic stress tolerance and seed dormancy. In previous studies, we evaluated ABA responsiveness of 67 Aegilops tauschii accessions and their synthetic hexaploid wheat lines, finding wide variation that was due to the D-genome. In this study, quantitative trait locus (QTL) analysis was performed using an F2 population derived from crosses of highly ABA-responsive and less-responsive synthetic wheat lines. A significant QTL was detected on chromosome 6D, in a similar location to that reported for ABA responsiveness using recombinant inbred lines derived from common wheat cultivars Mironovskaya 808 and Chinese Spring. A comparative map and physiological and expression analyses of the 6D QTL suggested that this locus involved in line differences among wheat synthetics is different from that involved in cultivar differences in common wheat. The common wheat 6D QTL was found to affect seed dormancy and the regulation of cold-responsive/late embryogenesis abundant genes during dehydration. However, in synthetic wheat, we failed to detect any association of ABA responsiveness with abiotic stress tolerance or seed dormancy, at least under our experimental conditions. Development of near-isogenic lines will be important for functional analyses of the synthetic wheat 6D QTL. PMID:24877675

  19. Molecular diversity of Omani wheat revealed by microsatellites: II. Hexaploid landraces

    Microsoft Academic Search

    S. Al Khanjari; K. Hammer; A. Buerkert; M. S. Röder

    2007-01-01

    For millennia, wheat (Triticum spp.) has been grown in traditional aflaj-irrigation systems of remote mountain oases in Oman. However, little is known about\\u000a the diversity of the ancient landraces used. Given recent reports about the occurrence of novel germplasm in such material,\\u000a the objective of this study was to evaluate the genetic diversity of hexaploid wheat (Triticum aestivum L.) landraces

  20. Spontaneous and Divergent Hexaploid Triticales Derived from Common Wheat × Rye by Complete Elimination of D-Genome Chromosomes

    PubMed Central

    Wang, Changyou; Ji, Wanquan

    2015-01-01

    Background Hexaploid triticale could be either synthesized by crossing tetraploid wheat with rye, or developed by crossing hexaploid wheat with a hexaploid triticale or an octoploid triticale. Methodology/Principal Findings Here two hexaploid triticales with great morphologic divergence derived from common wheat cultivar M8003 (Triticum aestivum L.) × Austrian rye (Secale cereale L.) were reported, exhibiting high resistance for powdery mildew and stripe rust and potential for wheat improvement. Sequential fluorescence in situ hybridization (FISH) and genomic in situ hybridization (GISH) karyotyping revealed that D-genome chromosomes were completely eliminated and the whole A-genome, B-genome and R-genome chromosomes were retained in both lines. Furthermore, plentiful alterations of wheat chromosomes including 5A and 7B were detected in both triticales and additionally altered 5B, 7A chromosome and restructured chromosome 2A was assayed in N9116H and N9116M, respectively, even after selfing for several decades. Besides, meiotic asynchrony was displayed and a variety of storage protein variations were assayed, especially in the HMW/LMW-GS region and secalins region in both triticales. Conclusion This study confirms that whole D-genome chromosomes could be preferentially eliminated in the hybrid of common wheat × rye, “genome shock” was accompanying the allopolyploidization of nascent triticales, and great morphologic divergence might result from the genetic variations. Moreover, new hexaploid triticale lines contributing potential resistance resources for wheat improvement were produced. PMID:25781330

  1. A chromosome-based draft sequence of the hexaploid bread wheat (Triticum aestivum) genome.

    PubMed

    2014-07-18

    An ordered draft sequence of the 17-gigabase hexaploid bread wheat (Triticum aestivum) genome has been produced by sequencing isolated chromosome arms. We have annotated 124,201 gene loci distributed nearly evenly across the homeologous chromosomes and subgenomes. Comparative gene analysis of wheat subgenomes and extant diploid and tetraploid wheat relatives showed that high sequence similarity and structural conservation are retained, with limited gene loss, after polyploidization. However, across the genomes there was evidence of dynamic gene gain, loss, and duplication since the divergence of the wheat lineages. A high degree of transcriptional autonomy and no global dominance was found for the subgenomes. These insights into the genome biology of a polyploid crop provide a springboard for faster gene isolation, rapid genetic marker development, and precise breeding to meet the needs of increasing food demand worldwide. PMID:25035500

  2. Transgene inheritance and silencing in hexaploid spring wheat

    Microsoft Academic Search

    T. Demeke; P. Hucl; M. Båga; K. Caswell; N. Leung; R. N. Chibbar

    1999-01-01

    Inheritance and expression of the Act1D-uidA::nptII transgene cassette inserted into the genome of a spring wheat cultivar, ’Fielder’, was studied in T4 and T5 transgenic wheat lines. Southern blot and PCR analyses demonstrated that the transgene was inherited for five generations\\u000a of selfed plants. The multiple integration pattern displayed in the T1 generation was maintained up to the T5 generation

  3. A new Hessian fly resistance gene ( H 30) transferred from the wild grass Aegilops triuncialis to hexaploid wheat

    Microsoft Academic Search

    J. A. Martín-Sánchez; M. Gómez-Colmenarejo; J. Del Moral; E. Sin; M. J. Montes; C. González-Belinchón; I. López-Braña; A. Delibes

    2003-01-01

    A new Hessian fly (Mayetiola destructor Say) resistance gene from Aegilops triuncialis and its transfer to hexaploid wheat via interspecific hybridisation is described. The transfer line TR-3531 (42 chromosomes), derived from the cross [(Triticum turgidum 2 Ae. triuncialis) 2 Triticum aestivum] and carrying the Heterodera avenae resistance gene Cre7, showed a high level of resistance to the M. destructor biotype

  4. New broad-spectrum resistance to septoria tritici blotch derived from synthetic hexaploid wheat.

    PubMed

    Tabib Ghaffary, S Mahmod; Faris, Justin D; Friesen, Timothy L; Visser, Richard G F; van der Lee, Theo A J; Robert, Olivier; Kema, Gert H J

    2012-01-01

    Septoria tritici blotch (STB), caused by the ascomycete Mycosphaerella graminicola, is one of the most devastating foliar diseases of wheat. We screened five synthetic hexaploid wheats (SHs), 13 wheat varieties that represent the differential set of cultivars and two susceptible checks with a global set of 20 isolates and discovered exceptionally broad STB resistance in SHs. Subsequent development and analyses of recombinant inbred lines (RILs) from a cross between the SH M3 and the highly susceptible bread wheat cv. Kulm revealed two novel resistance loci on chromosomes 3D and 5A. The 3D resistance was expressed in the seedling and adult plant stages, and it controlled necrosis (N) and pycnidia (P) development as well as the latency periods of these parameters. This locus, which is closely linked to the microsatellite marker Xgwm494, was tentatively designated Stb16q and explained from 41 to 71% of the phenotypic variation at seedling stage and 28-31% in mature plants. The resistance locus on chromosome 5A was specifically expressed in the adult plant stage, associated with SSR marker Xhbg247, explained 12-32% of the variation in disease, was designated Stb17, and is the first unambiguously identified and named QTL for adult plant resistance to M. graminicola. Our results confirm that common wheat progenitors might be a rich source of new Stb resistance genes/QTLs that can be deployed in commercial breeding programs. PMID:21912855

  5. Transcriptional profiling of hexaploid wheat (Triticum aestivum L.) roots identifies novel, dehydration-responsive genes.

    PubMed

    Mohammadi, Mohsen; Kav, Nat N V; Deyholos, Michael K

    2007-05-01

    We used a long-oligonucleotide microarray to identify transcripts that increased or decreased in abundance in roots of dehydration-tolerant hexaploid bread wheat, in response to withholding of water. We observed that the major classes of dehydration-responsive genes (e.g. osmoprotectants, compatible solutes, proteases, glycosyltransferases/hydrolases, signal transducers components, ion transporters) were generally similar to those observed previously in other species and osmotic stresses. More specifically, we highlighted increases in transcript expression for specific genes including those putatively related to the synthesis of asparagine, trehalose, oligopeptide transporters, metal-binding proteins, the gamma-aminobutyric acid (GABA) shunt and transcription factors. Conversely, we noted a decrease in transcript abundance for diverse classes of glutathione and sulphur-related enzymes, specific amino acids, as well as MATE-efflux carrier proteins. From these data, we identified a novel, dehydration-induced putative AP2/ERF transcription factor, which we predict to function as a transcriptional repressor. We also identified a dehydration-induced 'little protein' (LitP; predicted mass: 8 kDa) that is highly conserved across spermatophytes. Using qRT-PCR, we compared the expression patterns of selected genes between two related wheat genotypes that differed in their susceptibility to dehydration, and confirmed that these novel genes were highly inducible by water limitation in both genotypes, although the magnitude of induction differed. PMID:17407540

  6. Synthetic Hexaploid Wheat as a Source of Improvement for Winter Wheat (Triticum aestivum L.) in Texas 

    E-print Network

    Cooper, Jessica Kay

    2012-02-14

    backcrosses to spring wheats show improvement over recurrent parents (del Blanco et al., 2000; Lage et al., 2004a; Mujeeb-Kazi et al., 2008; Villareal et al., 1994) but evidence of the benefits of synthetic backcrosses to winter wheat is meager... of the grain. Resistance to pests such as Russian wheat aphid (Lage et al., 2004a; Lage et al., 2004b), greenbug (Lage et al., 2003) and Hessian fly (Coxand Hatchett, 1994; Friesen et al., 2008; Sardesai et al., 2005), all common biotic stress problems...

  7. Population divergence in the wheat leaf rust fungus Puccinia triticina is correlated with wheat evolution

    PubMed Central

    Liu, M; Rodrigue, N; Kolmer, J

    2014-01-01

    Co-evolution of fungal pathogens with their host species during the domestication of modern crop varieties has likely affected the current genetic divergence of pathogen populations. The objective of this study was to determine if the evolutionary history of the obligate rust pathogen on wheat, Puccinia triticina, is correlated with adaptation to hosts with different ploidy levels. Sequence data from 15 loci with different levels of polymorphism were generated. Phylogenetic analyses (parsimony, Bayesian, maximum likelihood) showed the clear initial divergence of P. triticina isolates collected from Aegilops speltoides (the likely B genome donor of modern wheat) in Israel from the other isolates that were collected from tetraploid (AB genomes) durum wheat and hexaploid (ABD genomes) common wheat. Coalescence-based genealogy samplers also indicated that P. triticina on A. speltoides, diverged initially, followed by P. triticina isolates from durum wheat in Ethiopia and then by isolates from common wheat. Isolates of P. triticina found worldwide on cultivated durum wheat were the most recently coalesced and formed a clade nested within the isolates from common wheat. By a relative time scale, the divergence of P. triticinia as delimited by host specificity appears very recent. Significant reciprocal gene flow between isolates from common wheat and isolates from durum wheat that are found worldwide was detected, in addition to gene flow from isolates on common wheat to isolates on durum wheat in Ethiopia. PMID:24301080

  8. Population divergence in the wheat leaf rust fungus Puccinia triticina is correlated with wheat evolution.

    PubMed

    Liu, M; Rodrigue, N; Kolmer, J

    2014-04-01

    Co-evolution of fungal pathogens with their host species during the domestication of modern crop varieties has likely affected the current genetic divergence of pathogen populations. The objective of this study was to determine if the evolutionary history of the obligate rust pathogen on wheat, Puccinia triticina, is correlated with adaptation to hosts with different ploidy levels. Sequence data from 15 loci with different levels of polymorphism were generated. Phylogenetic analyses (parsimony, Bayesian, maximum likelihood) showed the clear initial divergence of P. triticina isolates collected from Aegilops speltoides (the likely B genome donor of modern wheat) in Israel from the other isolates that were collected from tetraploid (AB genomes) durum wheat and hexaploid (ABD genomes) common wheat. Coalescence-based genealogy samplers also indicated that P. triticina on A. speltoides, diverged initially, followed by P. triticina isolates from durum wheat in Ethiopia and then by isolates from common wheat. Isolates of P. triticina found worldwide on cultivated durum wheat were the most recently coalesced and formed a clade nested within the isolates from common wheat. By a relative time scale, the divergence of P. triticinia as delimited by host specificity appears very recent. Significant reciprocal gene flow between isolates from common wheat and isolates from durum wheat that are found worldwide was detected, in addition to gene flow from isolates on common wheat to isolates on durum wheat in Ethiopia. PMID:24301080

  9. Coexistence of Tetraploid and Hexaploid Naked Wheat in a Neolithic Lake Dwelling of Central Europe: Evidence from Morphology and Ancient DNA

    Microsoft Academic Search

    Angela Schlumbaum; Jean-Marc Neuhaus; Stefanie Jacomet

    1998-01-01

    Free-threshing wheat was a principal cereal in Neolithic cultures, as shown by the abundance of grains in the archaeological record. However, the morphology of the mainly charred preserved, prehistoric naked wheat grains is not characteristic of either tetraploid,Triticum durumDesf. andTriticum turgidumL., or of hexaploid, e.g.Triticum aestivumL. We analysed the morphology of charred naked wheat grains originating from a storage assemblage

  10. Genome-wide association for grain morphology in synthetic hexaploid wheats using digital imaging analysis

    PubMed Central

    2014-01-01

    Background Grain size and shape greatly influence grain weight which ultimately enhances grain yield in wheat. Digital imaging (DI) based phenomic characterization can capture the three dimensional variation in grain size and shape than has hitherto been possible. In this study, we report the results from using digital imaging of grain size and shape to understand the relationship among different components of this trait, their contribution to enhance grain weight, and to identify genomic regions (QTLs) controlling grain morphology using genome wide association mapping with high density diversity array technology (DArT) and allele-specific markers. Results Significant positive correlations were observed between grain weight and grain size measurements such as grain length (r?=?0.43), width, thickness (r?=?0.64) and factor from density (FFD) (r?=?0.69). A total of 231 synthetic hexaploid wheats (SHWs) were grouped into five different sub-clusters by Bayesian structure analysis using unlinked DArT markers. Linkage disequilibrium (LD) decay was observed among DArT loci?>?10 cM distance and approximately 28% marker pairs were in significant LD. In total, 197 loci over 60 chromosomal regions and 79 loci over 31 chromosomal regions were associated with grain morphology by genome wide analysis using general linear model (GLM) and mixed linear model (MLM) approaches, respectively. They were mainly distributed on homoeologous group 2, 3, 6 and 7 chromosomes. Twenty eight marker-trait associations (MTAs) on the D genome chromosomes 2D, 3D and 6D may carry novel alleles with potential to enhance grain weight due to the use of untapped wild accessions of Aegilops tauschii. Statistical simulations showed that favorable alleles for thousand kernel weight (TKW), grain length, width and thickness have additive genetic effects. Allelic variations for known genes controlling grain size and weight, viz. TaCwi-2A, TaSus-2B, TaCKX6-3D and TaGw2-6A, were also associated with TKW, grain width and thickness. In silico functional analysis predicted a range of biological functions for 32 DArT loci and receptor like kinase, known to affect plant development, appeared to be common protein family encoded by several loci responsible for grain size and shape. Conclusion Conclusively, we demonstrated the application and integration of multiple approaches including high throughput phenotyping using DI, genome wide association studies (GWAS) and in silico functional analysis of candidate loci to analyze target traits, and identify candidate genomic regions underlying these traits. These approaches provided great opportunity to understand the breeding value of SHWs for improving grain weight and enhanced our deep understanding on molecular genetics of grain weight in wheat. PMID:24884376

  11. Variability and genetics of spacer DNA sequences between the ribosomal-RNA genes of hexaploid wheat (Triticum aestivum).

    PubMed

    May, C E; Appels, R

    1987-09-01

    Using restriction enzyme digests of genomic DNA extracted from the leaves of 25 hexaploid wheat (Triticum aestivum L. em. Thell.) cultivars and their hybrids, restriction fragment length polymorphisms of the spacer DNA which separates the ribosomal-RNA genes have been examined. (From one to three thousand of these genes are borne on chromosomes 1B and 6B of hexaploid wheat). The data show that there are three distinct alleles of the 1B locus, designated Nor-B1a, Nor-B1b, and Nor-B1c, and at least five allelic variants of the 6B locus, designated Nor-B2a, Nor-B2b, Nor-B2c, Nor-B2d, and Nor-B2e. A further, previously reported allele on 6B has been named Nor-B2f. Chromosome 5D has only one allelic variant, Nor-D3. Whereas the major spacer variants of the 1B alleles apparently differ by the loss or gain of one or two of the 133 bp sub-repeat units within the spacer DNA, the 6B allelic variants show major differences in their compositions and lengths. This may be related to the greater number of rDNA repeat units at this locus. The practical implications of these differences and their application to wheat breeding are discussed. PMID:24240218

  12. Determination of the linkage relationships and the gene-centromere genetic distances for endopeptidase structural genes in hexaploid wheat 

    E-print Network

    McMillin, David Edwin

    1977-01-01

    DETERNINATION OF THE 3' INKAGE RELATIONSHIPS AND THE GENE-CENTBQYZRZ GENETIC DISTANCES FOR ENDOPEPTIDASE STRUCTU~& GENES IN HEXAPLOID WHEAT A Thesis by DAVID EDWIN NcNILLIN Submitted to the Graduate College of Texas A6K University iri... partial fulfillrr~ent of the requirement for the degree of :PASTER OF SCIE'ACR Nay 1977 Hajor Sub-je" t: Gea, ties DETERMINATION OF THE LD'KACE kEM'). '. ~'OBBHZPS AND THi?: GENE-CENTF''ONEM GENETIC DIS'L&NCES FOR ENDOPEPTIDASE STRUCTURAL GENES IN H...

  13. [Analysis of wheat and rye semidwarfing gene distribution in spring hexaploid triticale (Triticosecale Wittm.) varieties and lines].

    PubMed

    Korshunova, A D; Divashchuk, M G; Solov'ev, A A; Karlov, G I

    2015-03-01

    A collection of spring hexaploid triticale varieties and promising breeding lines has been examined for the presence of wheat Rht-B1b, Rht-B1e, and Rht8c semidwarfing genes and the rye Hl semidwarfing gene. It was discovered in spring triticale that these semidwarfing genes are represented by only one, the Rht-B1b wheat gene. The presence of this gene is associated with shortening of spring triticale plants by 28 cm on average, which constituted 26% of their initial height. Rht-B1b was found in all of the studied commercial varieties of spring triticale, which rendered it possible to conclude that plant height reduction is a necessary condition for increasing the competitiveness of this crop culture. PMID:26027372

  14. Genotype-dependent Burst of Transposable Element Expression in Crowns of Hexaploid Wheat (Triticum aestivum L.) during Cold Acclimation

    PubMed Central

    Laudencia-Chingcuanco, Debbie; Fowler, D. Brian

    2012-01-01

    The expression of 1,613 transposable elements (TEs) represented in the Affymetrix Wheat Genome Chip was examined during cold treatment in crowns of four hexaploid wheat genotypes that vary in tolerance to cold and in flowering time. The TE expression profiles showed a constant level of expression throughout the experiment in three of the genotypes. In winter Norstar, the most cold-hardy of the four genotypes, a subset of the TEs showed a burst of expression after vernalization saturation was achieved. About 47% of the TEs were expressed, and both Class I (retrotransposons) and Class II (DNA transposons) types were well represented. Gypsy and Copia were the most represented among the retrotransposons while CACTA and Mariner were the most represented DNA transposons. The data suggests that the Vrn-A1 region plays a role in the stage-specific induction of TE expression in this genotype. PMID:22474410

  15. Whole genome QTL analysis of Stagonospora nodorum blotch resistance and validation of the SnTox4-Snn4 interaction in hexaploid wheat

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Abeysekara, N.S., Faris, J.D., Chao, S., McClean, P.E., and Friesen, T.L. 201_. Whole genome QTL analysis of Stagonospora nodorum blotch resistance and validation of the SnTox4- Snn4 interaction in hexaploid wheat. Phytopathology Necrotrophic effectors (also known as host-selective toxins) are impor...

  16. QTug.sau-3B Is a Major Quantitative Trait Locus for Wheat Hexaploidization

    PubMed Central

    Hao, Ming; Luo, Jiangtao; Zeng, Deying; Zhang, Li; Ning, Shunzong; Yuan, Zhongwei; Yan, Zehong; Zhang, Huaigang; Zheng, Youliang; Feuillet, Catherine; Choulet, Frédéric; Yen, Yang; Zhang, Lianquan; Liu, Dengcai

    2014-01-01

    Meiotic nonreduction resulting in unreduced gametes is thought to be the predominant mechanism underlying allopolyploid formation in plants. Until now, however, its genetic base was largely unknown. The allohexaploid crop common wheat (Triticum aestivum L.), which originated from hybrids of T. turgidum L. with Aegilops tauschii Cosson, provides a model to address this issue. Our observations of meiosis in pollen mother cells from T. turgidum×Ae. tauschii hybrids indicated that first division restitution, which exhibited prolonged cell division during meiosis I, was responsible for unreduced gamete formation. A major quantitative trait locus (QTL) for this trait, named QTug.sau-3B, was detected on chromosome 3B in two T. turgidum×Ae. tauschii haploid populations. This QTL is situated between markers Xgwm285 and Xcfp1012 and covered a genetic distance of 1 cM in one population. QTug.sau-3B is a haploid-dependent QTL because it was not detected in doubled haploid populations. Comparative genome analysis indicated that this QTL was close to Ttam-3B, a collinear homolog of tam in wheat. Although the relationship between QTug.sau-3B and Ttam requires further study, high frequencies of unreduced gametes may be related to reduced expression of Ttam in wheat. PMID:25128436

  17. Construction and Characterization of a Bacterial Artificial Chromosome Library for the Hexaploid Wheat Line 92R137

    PubMed Central

    Yuan, Fengping; Xu, Xin; Shi, Xue; Zhuang, Hua; Wang, Zhonghua; Huang, Lili; Han, Dejun; Kang, Zhensheng

    2014-01-01

    For map-based cloning of genes conferring important traits in the hexaploid wheat line 92R137, a bacterial artificial chromosome (BAC) library, including two sublibraries, was constructed using the genomic DNA of 92R137 digested with restriction enzymes HindIII and BamHI. The BAC library was composed of total 765,696 clones, of which 390,144 were from the HindIII digestion and 375,552 from the BamHI digestion. Through pulsed-field gel electrophoresis (PFGE) analysis of 453 clones randomly selected from the HindIII sublibrary and 573 clones from the BamHI sublibrary, the average insert sizes were estimated as 129 and 113?kb, respectively. Thus, the HindIII sublibrary was estimated to have a 3.01-fold coverage and the BamHI sublibrary a 2.53-fold coverage based on the estimated hexaploid wheat genome size of 16,700?Mb. The 765,696 clones were arrayed in 1,994 384-well plates. All clones were also arranged into plate pools and further arranged into 5-dimensional (5D) pools. The probability of identifying a clone corresponding to any wheat DNA sequence (such as gene Yr26 for stripe rust resistance) from the library was estimated to be more than 99.6%. Through polymerase chain reaction screening the 5D pools with Xwe173, a marker tightly linked to Yr26, six BAC clones were successfully obtained. These results demonstrate that the BAC library is a valuable genomic resource for positional cloning of Yr26 and other genes of interest. PMID:24895618

  18. mRNA and Small RNA Transcriptomes Reveal Insights into Dynamic Homoeolog Regulation of Allopolyploid Heterosis in Nascent Hexaploid Wheat.

    PubMed

    Li, Aili; Liu, Dengcai; Wu, Jun; Zhao, Xubo; Hao, Ming; Geng, Shuaifeng; Yan, Jun; Jiang, Xiaoxue; Zhang, Lianquan; Wu, Junyan; Yin, Lingjie; Zhang, Rongzhi; Wu, Liang; Zheng, Youliang; Mao, Long

    2014-05-16

    Nascent allohexaploid wheat may represent the initial genetic state of common wheat (Triticum aestivum), which arose as a hybrid between Triticum turgidum (AABB) and Aegilops tauschii (DD) and by chromosome doubling and outcompeted its parents in growth vigor and adaptability. To better understand the molecular basis for this success, we performed mRNA and small RNA transcriptome analyses in nascent allohexaploid wheat and its following generations, their progenitors, and the natural allohexaploid cultivar Chinese Spring, with the assistance of recently published A and D genome sequences. We found that nonadditively expressed protein-coding genes were rare but relevant to growth vigor. Moreover, a high proportion of protein-coding genes exhibited parental expression level dominance, with genes for which the total homoeolog expression level in the progeny was similar to that in T. turgidum potentially participating in development and those with similar expression to that in Ae. tauschii involved in adaptation. In addition, a high proportion of microRNAs showed nonadditive expression upon polyploidization, potentially leading to differential expression of important target genes. Furthermore, increased small interfering RNA density was observed for transposable element-associated D homoeologs in the allohexaploid progeny, which may account for biased repression of D homoeologs. Together, our data provide insights into small RNA-mediated dynamic homoeolog regulation mechanisms that may contribute to heterosis in nascent hexaploid wheat. PMID:24838975

  19. Lr34 multi-pathogen resistance ABC transporter: molecular analysis of homoeologous and orthologous genes in hexaploid wheat and other grass species.

    PubMed

    Krattinger, Simon G; Lagudah, Evans S; Wicker, Thomas; Risk, Joanna M; Ashton, Anthony R; Selter, Liselotte L; Matsumoto, Takashi; Keller, Beat

    2011-02-01

    The Triticum aestivum (bread wheat) disease resistance gene Lr34 confers durable, race non-specific protection against three fungal pathogens, and has been a highly relevant gene for wheat breeding since the green revolution. Lr34, located on chromosome 7D, encodes an ATP-binding cassette (ABC) transporter. Both wheat cultivars with and without Lr34-based resistance encode a putatively functional protein that differ by only two amino acid polymorphisms. In this study, we focused on the identification and characterization of homoeologous and orthologous Lr34 genes in hexaploid wheat and other grasses. In hexaploid wheat we found an expressed and putatively functional Lr34 homoeolog located on chromosome 4A, designated Lr34-B. Another homoeologous Lr34 copy, located on chromosome 7A, was disrupted by the insertion of repetitive elements. Protein sequences of LR34-B and LR34 were 97% identical. Orthologous Lr34 genes were detected in the genomes of Oryza sativa (rice) and Sorghum bicolor (sorghum). Zea mays (maize), Brachypodium distachyon and Hordeum vulgare (barley) lacked Lr34 orthologs, indicating independent deletion of this particular ABC transporter. Lr34 was part of a gene-rich island on the wheat D genome. We found gene colinearity on the homoeologous A and B genomes of hexaploid wheat, but little microcolinearity in other grasses. The homoeologous LR34-B protein and the orthologs from rice and sorghum have the susceptible haplotype for the two critical polymorphisms distinguishing the LR34 proteins from susceptible and resistant wheat cultivars. We conclude that the particular Lr34-haplotype found in resistant wheat cultivars is unique. It probably resulted from functional gene diversification that occurred after the polyploidization event that was at the origin of cultivated bread wheat. PMID:21265893

  20. Effects of different combinations of benzyl adenine and indole acetic acid concentrations on in vitro plant regeneration in hexaploid wheat.

    PubMed

    Fahmy, Ashraf H; Li, Jiarui; Abou El-Wafa, Walaa; El-Khodary, Soheir El-Saeed; El Shihy, Osama M

    2012-01-01

    Development of a reliable in vitro plant regeneration procedure for hexaploid bread wheat (Triticum aestivum L.) is a prerequisite for its improvement by genetic transformation. Here, we report the effects of two growth regulators, benzyl adenine (BA) and indole acetic acid (IAA) on callus induction and plant regeneration from scutellum cultures of two commercial bread wheat cultivars: Giza 164 and Sakha 69. Callus induction was obtained from isolated embryos cultured on modified Murashige and Skoog (MS) basal medium. After four weeks of callus induction, all calli were plated on MS basal medium for regeneration. Wheat genotype and callus induction medium played a dominant role in plantlet regeneration. 2.0 mg/L BA and 0.2 mg/L IAA were the best combinations for inducing callus and let to highest regeneration frequency (81.67%) across the cultivars. Overall, based on our medium conditions, Giza 164 displayed higher regeneration frequency (81.11%) than Sakha 69. These results will facilitate genetic transformation for the economic varieties Giza 164 and Sakha 69. PMID:22538227

  1. Marker Development and Saturation Mapping of the Tan Spot Ptr ToxB Sensitivity locus Tsc2 in Hexaploid Wheat

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Ptr ToxB is a host-selective toxin produced by the tan spot fungus that induces chlorosis in wheat lines harboring the Tsc2 gene, which was previously located to chromosome arm 2BS in tetraploid wheat. In this study, molecular mapping in a recombinant inbred (RI) population derived from a cross betw...

  2. Tandemly Duplicated Safener-Induced Glutathione S-Transferase Genes from Triticum tauschii Contribute to Genome- and Organ-Specific Expression in Hexaploid Wheat1

    PubMed Central

    Xu, Fangxiu; Lagudah, Evans S.; Moose, Stephen P.; Riechers, Dean E.

    2002-01-01

    Glutathione S-transferase (GST) gene expression was examined in several Triticum species, differing in genome constitution and ploidy level, to determine genome contribution to GST expression in cultivated, hexaploid bread wheat (Triticum aestivum). Two tandemly duplicated tau class GST genes (TtGSTU1 and TtGSTU2) were isolated from a single bacterial artificial chromosome clone in a library constructed from the diploid wheat and D genome progenitor to cultivated wheat, Triticum tauschii. The genes are very similar in genomic structure and their encoded proteins are 95% identical. Gene-specific reverse transcriptase-polymerase chain reaction analysis revealed differential transcript accumulation of TtGSTU1 and TtGSTU2 in roots and shoots. Expression of both genes was induced by herbicide safeners, 2,4-dichlorophenoxyacetic acid and abscisic acid, in the shoots of T. tauschii; however, expression of TtGSTU1 was always higher than TtGSTU2. In untreated seedlings, TtGSTU1 was expressed in both shoots and roots, whereas TtGSTU2 expression was only detected in roots. RNA gel-blot analysis of ditelosomic, aneuploid lines that are deficient for 6AS, 6BS, or 6DS chromosome arms of cultivated, hexaploid bread wheat showed differential genome contribution to safener-induced GST expression in shoots compared with roots. The GST genes from the D genome of hexaploid wheat contribute most to safener-induced expression in the shoots, whereas GSTs from the B and D genomes contribute to safener-induced expression in the roots. PMID:12226515

  3. Genome-wide identification and expression characterization of ABCC-MRP transporters in hexaploid wheat

    PubMed Central

    Bhati, Kaushal K.; Sharma, Shivani; Aggarwal, Sipla; Kaur, Mandeep; Shukla, Vishnu; Kaur, Jagdeep; Mantri, Shrikant; Pandey, Ajay K.

    2015-01-01

    The ABCC multidrug resistance associated proteins (ABCC-MRP), a subclass of ABC transporters are involved in multiple physiological processes that include cellular homeostasis, metal detoxification, and transport of glutathione-conjugates. Although they are well-studied in humans, yeast, and Arabidopsis, limited efforts have been made to address their possible role in crop like wheat. In the present work, 18 wheat ABCC-MRP proteins were identified that showed the uniform distribution with sub-families from rice and Arabidopsis. Organ-specific quantitative expression analysis of wheat ABCC genes indicated significantly higher accumulation in roots (TaABCC2, TaABCC3, and TaABCC11 and TaABCC12), stem (TaABCC1), leaves (TaABCC16 and TaABCC17), flag leaf (TaABCC14 and TaABCC15), and seeds (TaABCC6, TaABCC8, TaABCC12, TaABCC13, and TaABCC17) implicating their role in the respective tissues. Differential transcript expression patterns were observed for TaABCC genes during grain maturation speculating their role during seed development. Hormone treatment experiments indicated that some of the ABCC genes could be transcriptionally regulated during seed development. In the presence of Cd or hydrogen peroxide, distinct molecular expression of wheat ABCC genes was observed in the wheat seedlings, suggesting their possible role during heavy metal generated oxidative stress. Functional characterization of the wheat transporter, TaABCC13 a homolog of maize LPA1 confirms its role in glutathione-mediated detoxification pathway and is able to utilize adenine biosynthetic intermediates as a substrate. This is the first comprehensive inventory of wheat ABCC-MRP gene subfamily.

  4. Molecular markers based identification of diversity for drought tolerance in bread wheat varieties and synthetic hexaploids.

    PubMed

    Shah, Zahid Hussain; Munir, Muhammad; Kazi, Abdul Mujeeb; Mujtaba, Tahir; Ahmed, Zaheer

    2009-01-01

    The complexity of the wheat genome has delayed the development and application of molecular markers to this species and wheat now lies behind barley, maize and rice in marker development. However, improvements in marker detection systems and in the techniques used to identify markers linked to useful traits has allowed considerable advances to be made in recent years. To evaluate the genetic diversity 53 genotypes of Richard's selection, were studied at National Agriculture Reseach Center (NARC) Islamabad. The present study found that RAPD analysis is a valuable diagnostic tool. Different sets of RAPD primers were used to study the polymorphism at molecular level. Highest number of amplifications was shown by primer OpG-2 in Richard's material. Coefficient of similarity as well as genetic distances among these three sets of materials was calculated by using Unweighted Pair Group of Arithamatic Means (UPGMA) function (Nei and Li, 1979). The SHs derived genotypes of Richard's selection were highly polymorphic with a polymorphism percentage of 69.70 as compared to NUYT (rainfed) and elite Pakistani bread wheat varieties with a polymorphism of 44.44% and 61.11% respectively. Cluster analysis was done in which grouping of genotypes was done on the basis of genetic distances. Cluster analysis revealed that genotypes of Richard's genotypes are showing high level of among cultivar variation as compared to NUYT (Rainfed) and elite Pakistani drought tolerant bread wheat varieties. These genotypes were also phenotypically evaluated. PMID:19430030

  5. A Point Mutation Demonstrating the Pleiotropic Effects of the Domestication Gene Q in Hexaploid Wheat

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The Q gene is a major domestication gene in wheat because it confers the free-threshing character and pleiotropically influences many other crop-related agronomic traits. Q is a member of the APETALA2 (AP2) family of transcription factors. Here, we created a Q-disrupted mutant in the Triticum aestiv...

  6. Phenotyping pipeline reveals major seedling root growth QTL in hexaploid wheat

    PubMed Central

    Atkinson, Jonathan A.; Wingen, Luzie U.; Griffiths, Marcus; Pound, Michael P.; Gaju, Oorbessy; Foulkes, M. John; Le Gouis, Jacques; Griffiths, Simon; Bennett, Malcolm J.; King, Julie; Wells, Darren M.

    2015-01-01

    Seedling root traits of wheat (Triticum aestivum L.) have been shown to be important for efficient establishment and linked to mature plant traits such as height and yield. A root phenotyping pipeline, consisting of a germination paper-based screen combined with image segmentation and analysis software, was developed and used to characterize seedling traits in 94 doubled haploid progeny derived from a cross between the winter wheat cultivars Rialto and Savannah. Field experiments were conducted to measure mature plant height, grain yield, and nitrogen (N) uptake in three sites over 2 years. In total, 29 quantitative trait loci (QTLs) for seedling root traits were identified. Two QTLs for grain yield and N uptake co-localize with root QTLs on chromosomes 2B and 7D, respectively. Of the 29 root QTLs identified, 11 were found to co-localize on 6D, with four of these achieving highly significant logarithm of odds scores (>20). These results suggest the presence of a major-effect gene regulating seedling root vigour/growth on chromosome 6D. PMID:25740921

  7. Preferential elimination of chromosome 1D from homoeologous group-1 alien addition lines in hexaploid wheat.

    PubMed

    Garg, Monika; Elamein, Hala M M; Tanaka, Hiroyuki; Tsujimoto, Hisashi

    2007-10-01

    Alien chromosome addition lines are useful genetic material for studying the effect of an individual chromosome in the same genetic background. However, addition lines are sometimes unstable and tend to lose the alien chromosome in subsequent generations. In this study, we report preferential removal of chromosome 1D rather than the alien chromosome from homoeologous group-1 addition lines. The Agropyron intermedium chromosome 1Agi (1E) addition line, created in the background of 'Vilmorin 27', showed loss of a part of chromosome 1D, thereby losing its HMW glutenin locus. Even in the case of Aegilops longissima and Ae. peregrina, the genomes of which are closer to the B genome than D genome, chromosome 1D was lost from chromosome 1Sl and 1Sv addition lines in cv. 'Chinese Spring' rather than chromosome 1B during transfer from one generation to another. A similar observation was also observed in the case of a chromosome 1E disomic addition line of Ag. elongatum and alloplasmic common wheat line with Ag. intermedium ssp. trichophorum cytoplasm. The reason for this strange observation is thought to lie in the history of wheat evolution, the size of chromosome 1D compared to 1A and 1B, or differing pollen competition abilities. PMID:17991995

  8. Molecular characterization and chromosomal localization of cytochrome P450 genes involved in the biosynthesis of cyclic hydroxamic acids in hexaploid wheat

    Microsoft Academic Search

    T. Nomura; A. Ishihara; H. Imaishi; T. Endo; H. Ohkawa; H. Iwamura

    2002-01-01

    The cyclic hydroxamic acids, 2,4-dihydroxy-1,4-benzoxazin-3-one (DIBOA) and 2,4-dihydroxy-7-methoxy-1,4-benzoxazin-3-one (DIMBOA), are defensive secondary metabolites found in gramineous plants including wheat, maize and rye. cDNAs for five cytochromes P450 (P450s) involved in DIBOA biosynthesis (CYP71C6, CYP71C7v2, CYP71C8v2, CYP71C9v1 and CYP71C9v2) were isolated from seedlings of hexaploid wheat [(Triticum aestivum L. cv. Chinese Spring (2n=6x=42, genomes AABBDD)] by RT-PCR and screening of a

  9. Transcriptomic Analysis of Starch Biosynthesis in the Developing Grain of Hexaploid Wheat

    PubMed Central

    Stamova, Boryana S.; Laudencia-Chingcuanco, Debbie; Beckles, Diane M.

    2009-01-01

    The expression of genes involved in starch synthesis in wheat was analyzed together with the accumulation profiles of soluble sugars, starch, protein, and starch granule distribution in developing caryopses obtained from the same biological materials used for profiling of gene expression using DNA microarrays. Multiple expression patterns were detected for the different starch biosynthetic gene isoforms, suggesting their relative importance through caryopsis development. Members of the ADP-glucose pyrophosphorylase, starch synthase, starch branching enzyme, and sucrose synthase gene families showed different expression profiles; expression of some members of these gene families coincided with a period of high accumulation of starch while others did not. A biphasic pattern was observed in the rates of starch and protein accumulation which paralleled changes in global gene expression. Metabolic and regulatory genes that show a pattern of expression similar to starch accumulation and granule size distribution were identified, suggesting their coinvolvement in these biological processes. PMID:20224818

  10. USE OF A LARGE-SCALE TRITICEAE EST RESOURCE TO REVEAL GENE EXPRESSION PROFILES IN HEXAPLOID WHEAT (TRITICUM AESTIVUM L.)

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Large-scale EST sequencing projects have been carried out in many higher plants and have proven critically important for plants where whole genome sequences are known; i.e., in Arabidopsis and rice (Oryza sativa L.) EST data have assisted in locating gene regions and splice junctions. Hexaploid brea...

  11. Identification of transposons, retroelements, and a gene family predominantly expressed in floral tissues in chromosome 3DS of the hexaploid wheat progenitor Aegilops tauschii.

    PubMed

    Whitford, Ryan; Baumann, Ute; Sutton, Tim; Gumaelius, Luke; Wolters, Petra; Tingey, Scott; Able, Jason A; Langridge, Peter

    2007-01-01

    A multigene family expressed during early floral development was identified on the short arm of wheat chromosome 3D in the region of the Ph2 locus, a locus controlling homoeologous chromosome pairing in allohexaploid wheat. Physical, genetic and molecular characterisation of the Wheat Meiosis 1 (WM1) gene family identified seven members that localised within a region of 173-kb. WM1 gene family members were sequenced and they encode mainly type Ia plasma membrane-anchored leucine rich repeat-like receptor proteins. In situ expression profiling suggests the gene family is predominantly expressed in floral tissue. In addition to the WM1 gene family, a number of other genes, gene fragments and pseudogenes were identified. It has been predicted that there is approximately one gene every 19-kb and that this region of the wheat genome contains 23 repetitive elements including BARE-1 and Wis2-1 like sequences. Nearly 50% of the repetitive elements identified were similar to known transposons from the CACTA superfamily. Ty1-copia, Ty3-gypsy and Athila LTR retroelements were also prevalent within the region. The WM1 gene cluster is present on 3DS and on barley 3HS but missing from the A and B genomes of hexaploid wheat. This suggests either recent generation of the cluster or specific deletion of the cluster during wheat polyploidisation. The evolutionary significance of the cluster, its possible roles in disease response or floral and early meiotic development and its location at or near the Ph2 locus are discussed. PMID:16534632

  12. Analysis of intraspecies diversity in wheat and barley genomes identifies breakpoints of ancient haplotypes and provides insight into the structure of diploid and hexaploid triticeae gene pools.

    PubMed

    Wicker, Thomas; Krattinger, Simon G; Lagudah, Evans S; Komatsuda, Takao; Pourkheirandish, Mohammad; Matsumoto, Takashi; Cloutier, Sylvie; Reiser, Laurenz; Kanamori, Hiroyuki; Sato, Kazuhiro; Perovic, Dragan; Stein, Nils; Keller, Beat

    2009-01-01

    A large number of wheat (Triticum aestivum) and barley (Hordeum vulgare) varieties have evolved in agricultural ecosystems since domestication. Because of the large, repetitive genomes of these Triticeae crops, sequence information is limited and molecular differences between modern varieties are poorly understood. To study intraspecies genomic diversity, we compared large genomic sequences at the Lr34 locus of the wheat varieties Chinese Spring, Renan, and Glenlea, and diploid wheat Aegilops tauschii. Additionally, we compared the barley loci Vrs1 and Rym4 of the varieties Morex, Cebada Capa, and Haruna Nijo. Molecular dating showed that the wheat D genome haplotypes diverged only a few thousand years ago, while some barley and Ae. tauschii haplotypes diverged more than 500,000 years ago. This suggests gene flow from wild barley relatives after domestication, whereas this was rare or absent in the D genome of hexaploid wheat. In some segments, the compared haplotypes were very similar to each other, but for two varieties each at the Rym4 and Lr34 loci, sequence conservation showed a breakpoint that separates a highly conserved from a less conserved segment. We interpret this as recombination breakpoints of two ancient haplotypes, indicating that the Triticeae genomes are a heterogeneous and variable mosaic of haplotype fragments. Analysis of insertions and deletions showed that large events caused by transposable element insertions, illegitimate recombination, or unequal crossing over were relatively rare. Most insertions and deletions were small and caused by template slippage in short homopolymers of only a few base pairs in size. Such frequent polymorphisms could be exploited for future molecular marker development. PMID:19011002

  13. RNA-Seq bulked segregant analysis enables the identification of high-resolution genetic markers for breeding in hexaploid wheat.

    PubMed

    Ramirez-Gonzalez, Ricardo H; Segovia, Vanesa; Bird, Nicholas; Fenwick, Paul; Holdgate, Sarah; Berry, Simon; Jack, Peter; Caccamo, Mario; Uauy, Cristobal

    2015-06-01

    The identification of genetic markers linked to genes of agronomic importance is a major aim of crop research and breeding programmes. Here, we identify markers for Yr15, a major disease resistance gene for wheat yellow rust, using a segregating F2 population. After phenotyping, we implemented RNA sequencing (RNA-Seq) of bulked pools to identify single-nucleotide polymorphisms (SNP) associated with Yr15. Over 27 000 genes with SNPs were identified between the parents, and then classified based on the results from the sequenced bulks. We calculated the bulk frequency ratio (BFR) of SNPs between resistant and susceptible bulks, selecting those showing sixfold enrichment/depletion in the corresponding bulks (BFR > 6). Using additional filtering criteria, we reduced the number of genes with a putative SNP to 175. The 35 SNPs with the highest BFR values were converted into genome-specific KASP assays using an automated bioinformatics pipeline (PolyMarker) which circumvents the limitations associated with the polyploid wheat genome. Twenty-eight assays were polymorphic of which 22 (63%) mapped in the same linkage group as Yr15. Using these markers, we mapped Yr15 to a 0.77-cM interval. The three most closely linked SNPs were tested across varieties and breeding lines representing UK elite germplasm. Two flanking markers were diagnostic in over 99% of lines tested, thus providing a reliable haplotype for marker-assisted selection in these breeding programmes. Our results demonstrate that the proposed methodology can be applied in polyploid F2 populations to generate high-resolution genetic maps across target intervals. PMID:25382230

  14. Molecular characterization of the puroindoline-a and b alleles in synthetic hexaploid wheats and in silico functional and structural insights into Pina-D1.

    PubMed

    Ali, Iftikhar; Sardar, Zainab; Rasheed, Awais; Mahmood, Tariq

    2015-07-01

    Kernel hardness determined by two tightly linked Puroindoline genes, Pina-D1 and Pinb-D1, located on chromosome 5DS define commercially important characteristics, uses, major grades and export markets of wheat. This study was conducted to characterize Pina-D1 and Pinb-D1 alleles, in fifteen synthetic hexaploid wheats (SHWs) and its relation with grain hardness. Additionally, in silico functional analyses of puroindoline-a protein was conducted for better understanding of their putative importance in grain quality. Six different Pina-D1 alleles were identified in the SHWs, of which three i.e. Pina-D1a, Pina-D1c and Pina-D1d were already known whereas the other three had new sequence polymorphisms and were designated as Pina-D1w, Pina-D1x and Pina-D1y. Three different Pinb-D1 alleles were identified which have been reported earlier and no novel sequence polymorphism was detected. It was concluded that despite some primary, secondary and 3D structure variations, ligand binding sites and disulfide bonds discrepancies, the main features of PINA, i.e. the tryptophan-rich domain, the cysteine backbone, the signal peptide and basic identity of the proteins were all conserved. In silico analysis showed that puroindolines having binding capacity with small parts of prolamins causing celiac disease of human, however their potential role is not obvious. Conclusively, the new Pina-D1 alleles with modest effect on grain hardness, and insight into their functional and structural characteristics are important findings and their putative role in celiac disease require further studies to validate. PMID:25865523

  15. Frequency and fidelity of alien chromosome transmission in Gossypium hexaploid bridging populations.

    PubMed

    Becerra Lopez-Lavalle, L Augusto; Brubaker, Curt L

    2007-05-01

    The Australian diploid Gossypium species possess traits of potential agronomical value, such as gossypol-free seeds and Fusarium wilt resistance. However, they belong to the tertiary germplasm pool, which is the most difficult group of species from which to introgress genes into G. barbadense L. and G. hirsutum L. Interspecific triploid hybrids can be generated but they are sterile. The sterility barrier can be overcome using synthetic polyploids as introgression bridges, but whether there is sufficient homoeologous chromosome interaction at meiosis to allow recombination is still an open question. To ascertain, genetically, observable levels of homoeologous introgression, 2 synthetic hexaploid lines (2x G. hirsutum x G. australe and 2x G. hirsutum x G. sturtianum) were crossed to G. hirsutum to generate pentaploid F1 plants that, in turn, were backcrossed to G. hirsutum to generate BC1 and BC2 multiple alien chromosome addition lines (MACALs). Gossypium australe F. Muell. and G. sturtianum Willis chromosome-specific markers were used to track the frequency and fidelity of chromosome transmission to the BC1 and BC2 MACALs. The chromosomal location of the AFLP markers was determined by their distribution among the MACALs and confirmed in parental F2 families. Roughly half the available chromosomes were transmitted to the G. hirsutum x G. australe (54%) and G. hirsutum x G. sturtianum (52%) BC1 MACALs. The BC2 MACAL families again inherited about half of the available chromosomes. There were, however, notable exceptions for specific chromosomes. Some chromosomes were preferentially eliminated, while others were preferentially transmitted. Consistent with the genomic stability of Gossypium synthetic polyploids, the de novo loss or gain of AFLP fragments was rarely observed. While restructuring of the donor G. australe and G. sturtianum chromosomes was observed, this is more likely the result of chromatin loss, and no clear cases of introgression of donor chromatin into the recipient G. hirsutum genome were observed. PMID:17612617

  16. Genome-wide association mapping for resistance to leaf and stripe rust in winter-habit hexaploid wheat landraces

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Leaf rust, caused by Puccinia triticina (Pt), and stripe rust, caused by P. striiformis f. sp. tritici (Pst), are destructive foliar diseases of wheat worldwide. Breeding for disease resistance is the preferred strategy of managing both diseases. The continued emergence of new races of Pt and Pst re...

  17. Synthesis and cytological analyses of hybrids between hexaploid wheat, with and without Ph1, and diploid wheatgrass

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The usefulness of wide hybridization in genetic enhancement of crop plants is well documented. Diploid wheatgrass is a source of several desirable traits including Fusarium head blight resistance. The objective of this study was to report on the synthesis and cytological analyses of wheat × wheatg...

  18. Genome-wide comparative diversity uncovers multiple targets of selection for improvement in hexaploid wheat landrace and cultivars

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Domesticated crops have experienced strong human-driven selection aimed at the development of improved varieties adapted to local conditions. To detect regions of the wheat genome subject to selection during improvement, we developed a high-throughput array to interrogate 9,000 gene-associated DNA m...

  19. Original article Divergent evolution of wheat populations conducted

    E-print Network

    Paris-Sud XI, Université de

    Original article Divergent evolution of wheat populations conducted under recurrent selection- ic management programme (DM) were studied in a wheat composite population. The initial population by few traits: plant height, earliness, frequency of bearded plants and susceptibility to powdery mildew

  20. Development and Characterization of a New TILLING Population of Common Bread Wheat (Triticum aestivum L.)

    PubMed Central

    Chen, Liang; Huang, Linzhou; Min, Donghong; Phillips, Andy; Wang, Shiqiang; Madgwick, Pippa J.; Parry, Martin A. J.; Hu, Yin-Gang

    2012-01-01

    Mutagenesis is an important tool in crop improvement. However, the hexaploid genome of wheat (Triticum aestivum L.) presents problems in identifying desirable genetic changes based on phenotypic screening due to gene redundancy. TILLING (Targeting Induced Local Lesions IN Genomes), a powerful reverse genetic strategy that allows the detection of induced point mutations in individuals of the mutagenized populations, can address the major challenge of linking sequence information to the biological function of genes and can also identify novel variation for crop breeding. Wheat is especially well-suited for TILLING due to the high mutation densities tolerated by polyploids. However, only a few wheat TILLING populations are currently available in the world, which is far from satisfying the requirement of researchers and breeders in different growing environments. In addition, current TILLING screening protocols require costly fluorescence detection systems, limiting their use, especially in developing countries. We developed a new TILLING resource comprising 2610 M2 mutants in a common wheat cultivar ‘Jinmai 47’. Numerous phenotypes with altered morphological and agronomic traits were observed from the M2 and M3 lines in the field. To simplify the procedure and decrease costs, we use unlabeled primers and either non-denaturing polyacrylamide gels or agarose gels for mutation detection. The value of this new resource was tested using PCR with RAPD and Intron-spliced junction (ISJ) primers, and also TILLING in three selected candidate genes, in 300 and 512 mutant lines, revealing high mutation densities of 1/34 kb by RAPD/ISJ analysis and 1/47 kb by TILLING. In total, 31 novel alleles were identified in the 3 targeted genes and confirmed by sequencing. The results indicate that this mutant population represents a useful resource for the wheat research community. We hope that the use of this reverse genetics resource will provide novel allelic diversity for wheat improvement and functional genomics. PMID:22844501

  1. Population- and genome-specific patterns of linkage disequilibrium and SNP variation in spring and winter wheat (Triticum aestivum L.)

    PubMed Central

    2010-01-01

    Background Single nucleotide polymorphisms (SNPs) are ideally suited for the construction of high-resolution genetic maps, studying population evolutionary history and performing genome-wide association mapping experiments. Here, we used a genome-wide set of 1536 SNPs to study linkage disequilibrium (LD) and population structure in a panel of 478 spring and winter wheat cultivars (Triticum aestivum) from 17 populations across the United States and Mexico. Results Most of the wheat oligo pool assay (OPA) SNPs that were polymorphic within the complete set of 478 cultivars were also polymorphic in all subpopulations. Higher levels of genetic differentiation were observed among wheat lines within populations than among populations. A total of nine genetically distinct clusters were identified, suggesting that some of the pre-defined populations shared significant proportion of genetic ancestry. Estimates of population structure (FST) at individual loci showed a high level of heterogeneity across the genome. In addition, seven genomic regions with elevated FST were detected between the spring and winter wheat populations. Some of these regions overlapped with previously mapped flowering time QTL. Across all populations, the highest extent of significant LD was observed in the wheat D-genome, followed by lower LD in the A- and B-genomes. The differences in the extent of LD among populations and genomes were mostly driven by differences in long-range LD ( > 10 cM). Conclusions Genome- and population-specific patterns of genetic differentiation and LD were discovered in the populations of wheat cultivars from different geographic regions. Our study demonstrated that the estimates of population structure between spring and winter wheat lines can identify genomic regions harboring candidate genes involved in the regulation of growth habit. Variation in LD suggests that breeding and selection had a different impact on each wheat genome both within and among populations. The higher extent of LD in the wheat D-genome versus the A- and B-genomes likely reflects the episodes of recent introgression and population bottleneck accompanying the origin of hexaploid wheat. The assessment of LD and population structure in this assembled panel of diverse lines provides critical information for the development of genetic resources for genome-wide association mapping of agronomically important traits in wheat. PMID:21190581

  2. Genome-Wide Association Mapping for Resistance to Leaf and Stripe Rust in Winter-Habit Hexaploid Wheat Landraces.

    PubMed

    Kertho, Albert; Mamidi, Sujan; Bonman, J Michael; McClean, Phillip E; Acevedo, Maricelis

    2015-01-01

    Leaf rust, caused by Puccinia triticina (Pt), and stripe rust, caused by P. striiformis f. sp. tritici (Pst), are destructive foliar diseases of wheat worldwide. Breeding for disease resistance is the preferred strategy of managing both diseases. The continued emergence of new races of Pt and Pst requires a constant search for new sources of resistance. Here we report a genome-wide association analysis of 567 winter wheat (Triticum aestivum) landrace accessions using the Infinium iSelect 9K wheat SNP array to identify loci associated with seedling resistance to five races of Pt (MDCL, MFPS, THBL, TDBG, and TBDJ) and one race of Pst (PSTv-37) frequently found in the Northern Great Plains of the United States. Mixed linear models identified 65 and eight significant markers associated with leaf rust and stripe rust, respectively. Further, we identified 31 and three QTL associated with resistance to Pt and Pst, respectively. Eleven QTL, identified on chromosomes 3A, 4A, 5A, and 6D, are previously unknown for leaf rust resistance in T. aestivum. PMID:26076040

  3. Genome-Wide Association Mapping for Resistance to Leaf and Stripe Rust in Winter-Habit Hexaploid Wheat Landraces

    PubMed Central

    Kertho, Albert; Mamidi, Sujan; Bonman, J. Michael; McClean, Phillip E.; Acevedo, Maricelis

    2015-01-01

    Leaf rust, caused by Puccinia triticina (Pt), and stripe rust, caused by P. striiformis f. sp. tritici (Pst), are destructive foliar diseases of wheat worldwide. Breeding for disease resistance is the preferred strategy of managing both diseases. The continued emergence of new races of Pt and Pst requires a constant search for new sources of resistance. Here we report a genome-wide association analysis of 567 winter wheat (Triticum aestivum) landrace accessions using the Infinium iSelect 9K wheat SNP array to identify loci associated with seedling resistance to five races of Pt (MDCL, MFPS, THBL, TDBG, and TBDJ) and one race of Pst (PSTv-37) frequently found in the Northern Great Plains of the United States. Mixed linear models identified 65 and eight significant markers associated with leaf rust and stripe rust, respectively. Further, we identified 31 and three QTL associated with resistance to Pt and Pst, respectively. Eleven QTL, identified on chromosomes 3A, 4A, 5A, and 6D, are previously unknown for leaf rust resistance in T. aestivum. PMID:26076040

  4. Mapping and validation of QTL which confer partial resistance to broadly virulent post-2000 North American races of stripe rust in hexaploid wheat

    Microsoft Academic Search

    Iago Lowe; Ljupcho Jankuloski; Shiaoman Chao; Xianming Chen; Deven See; Jorge Dubcovsky

    2011-01-01

    A mapping population of 186 recombinant inbred lines developed from a cross between UC1110, an adapted California spring wheat,\\u000a and PI610750, a synthetic derivative from CIMMYT’s Wide Cross Program, was evaluated for its response to current California\\u000a races of stripe rust (Puccinia striiformis f. sp. tritici) in replicated field trials over four seasons (2007–2010) in the northern Sacramento Valley. A

  5. Identification of seed dormancy for four populations derived from synthetic hexaploid wheat

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Seed dormancy is a key adaptive trait for wild species and is also a major domestication-related trait for crop species. Cereal cultivars have been selected for rapid, uniform germination during domestication and breeding and consequently, they generally have an insufficient degree of seed dormancy ...

  6. Wheat in the Mediterranean revisited – tetraploid wheat landraces assessed with elite bread wheat Single Nucleotide Polymorphism markers

    PubMed Central

    2014-01-01

    Background Single Nucleotide Polymorphism (SNP) panels recently developed for the assessment of genetic diversity in wheat are primarily based on elite varieties, mostly those of bread wheat. The usefulness of such SNP panels for studying wheat evolution and domestication has not yet been fully explored and ascertainment bias issues can potentially affect their applicability when studying landraces and tetraploid ancestors of bread wheat. We here evaluate whether population structure and evolutionary history can be assessed in tetraploid landrace wheats using SNP markers previously developed for the analysis of elite cultivars of hexaploid wheat. Results We genotyped more than 100 tetraploid wheat landraces and wild emmer wheat accessions, some of which had previously been screened with SSR markers, for an existing SNP panel and obtained publically available genotypes for the same SNPs for hexaploid wheat varieties and landraces. Results showed that quantification of genetic diversity can be affected by ascertainment bias but that the effects of ascertainment bias can at least partly be alleviated by merging SNPs to haplotypes. Analyses of population structure and genetic differentiation show strong subdivision between the tetraploid wheat subspecies, except for durum and rivet that are not separable. A more detailed population structure of durum landraces could be obtained than with SSR markers. The results also suggest an emmer, rather than durum, ancestry of bread wheat and with gene flow from wild emmer. Conclusions SNP markers developed for elite cultivars show great potential for inferring population structure and can address evolutionary questions in landrace wheat. Issues of marker genome specificity and mapping need, however, to be addressed. Ascertainment bias does not seem to interfere with the ability of a SNP marker system developed for elite bread wheat accessions to detect population structure in other types of wheat. PMID:24885044

  7. Analysis of Intraspecies Diversity in Wheat and Barley Genomes Identifies Breakpoints of Ancient Haplotypes and Provides Insight into the Structure of Diploid and Hexaploid Triticeae Gene Pools1[OA

    PubMed Central

    Wicker, Thomas; Krattinger, Simon G.; Lagudah, Evans S.; Komatsuda, Takao; Pourkheirandish, Mohammad; Matsumoto, Takashi; Cloutier, Sylvie; Reiser, Laurenz; Kanamori, Hiroyuki; Sato, Kazuhiro; Perovic, Dragan; Stein, Nils; Keller, Beat

    2009-01-01

    A large number of wheat (Triticum aestivum) and barley (Hordeum vulgare) varieties have evolved in agricultural ecosystems since domestication. Because of the large, repetitive genomes of these Triticeae crops, sequence information is limited and molecular differences between modern varieties are poorly understood. To study intraspecies genomic diversity, we compared large genomic sequences at the Lr34 locus of the wheat varieties Chinese Spring, Renan, and Glenlea, and diploid wheat Aegilops tauschii. Additionally, we compared the barley loci Vrs1 and Rym4 of the varieties Morex, Cebada Capa, and Haruna Nijo. Molecular dating showed that the wheat D genome haplotypes diverged only a few thousand years ago, while some barley and Ae. tauschii haplotypes diverged more than 500,000 years ago. This suggests gene flow from wild barley relatives after domestication, whereas this was rare or absent in the D genome of hexaploid wheat. In some segments, the compared haplotypes were very similar to each other, but for two varieties each at the Rym4 and Lr34 loci, sequence conservation showed a breakpoint that separates a highly conserved from a less conserved segment. We interpret this as recombination breakpoints of two ancient haplotypes, indicating that the Triticeae genomes are a heterogeneous and variable mosaic of haplotype fragments. Analysis of insertions and deletions showed that large events caused by transposable element insertions, illegitimate recombination, or unequal crossing over were relatively rare. Most insertions and deletions were small and caused by template slippage in short homopolymers of only a few base pairs in size. Such frequent polymorphisms could be exploited for future molecular marker development. PMID:19011002

  8. Spring Wheat Breeding

    Microsoft Academic Search

    M. Mergoum; P. K. Singh; J. A. Anderson; R. J. Peña; R. P. Singh; S. S. Xu; J. K. Ransom

    Wheat (various species of the genus Triticum) is a grass originating from the Levant area of the Middle East. However, only hexaploid common wheat (Triticum eastivum), and tetraploid durum wheat (Triticum turgidum ssp. durum) are presently cultivated worldwide. Not only is wheat an important crop today, it may well have influenced human history.\\u000a Wheat was a key factor enabling the

  9. Effectiveness of Lacewing Larvae in Reducing Russian Wheat Aphid Populations on Susceptible and Resistant Wheat

    Microsoft Academic Search

    Frank J. Messina; Suzann M. Sorenson

    2001-01-01

    The use of resistant plants may enhance or reduce the ability of natural enemies to control pest insects. We conducted a series of experiments to compare the effectiveness of lacewing larvae, Chrysoperla plorabunda (Fitch), in suppressing populations of the Russian wheat aphid, Diuraphis noxia (Mordvilko), on susceptible and resistant wheat. Caged plants were inoculated with the same initial density of

  10. Analysis of Intraspecies Diversity in Wheat and Barley Genomes Identifies Breakpoints of Ancient Haplotypes and Provides Insight into the Structure of Diploid and Hexaploid Triticeae Gene Pools

    Microsoft Academic Search

    Thomas Wicker; Simon G. Krattinger; Evans S. Lagudah; Takao Komatsuda; Mohammad Pourkheirandish; Takashi Matsumoto; Sylvie Cloutier; Laurenz Reiser; Hiroyuki Kanamori; Kazuhiro Sato; Dragan Perovic; Nils Stein; Beat Keller

    2009-01-01

    A large number of wheat (Triticum aestivum) and barley (Hordeum vulgare) varieties have evolved in agricultural ecosystems since domestication. Because of the large, repetitive genomes of these Triticeae crops, sequence information is limited and molecular differences between modern varieties are poorly understood. To study intraspecies genomic diversity, we compared large genomic sequences at the Lr34 locus of the wheat varieties

  11. Re-Evaluation of a Tetraploid Wheat Population Indicates That the Tsn1-ToxA Interaction is the Only Factor Governing Stagonospora Nodorum Blotch Susceptibility

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The wheat Tsn1 gene on chromosome 5B confers sensitivity to the host-selective toxin ToxA produced by the pathogens that cause tan spot and Stagonospora nodorum blotch (SNB). A compatible Tsn1-ToxA interaction is known to play a major role in conferring susceptibility of hexaploid (common) wheat to...

  12. Evolution and Balanced Gene Expression of Homoeologs in Polyploid Wheat

    E-print Network

    Gill, Kulvinder

    Evolution and Balanced Gene Expression of Homoeologs in Polyploid Wheat ABSTRACT . RESULTS AND DISCUSSION Hexaploid wheat is a relatively young polyploid with its evolution from diploid to tetraploid ~ .5 MYA and from tetraploid to hexaploid only ~10,000 years ago. The wheat genome is large of which only

  13. Hemi-nested touchdown PCR combined with primer-template mismatch PCR for rapid isolation and sequencing of low molecular weight glutenin subunit gene family from a hexaploid wheat BAC library

    PubMed Central

    Huang, Xiu-Qiang; Cloutier, Sylvie

    2007-01-01

    Background Hexaploid wheat (Triticum aestivum L.) possesses a large genome that contains 1.6 × 1010 bp of DNA. Isolation of a large number of gene sequences from complex gene families with a high level of gene sequence identity from genomic DNA is therefore difficult and time-consuming. Bacterial artificial chromosome (BAC) libraries can be useful for such work. Here we report on an efficient approach for rapid isolation and sequencing of the low molecular weight glutenin subunit gene family from the 'Glenlea' wheat BAC library via primer-template mismatch PCR using universal primers, primer walking using hemi-nested touchdown (TD) PCR, and followed by direct sequencing of PCR products. Results For the primer-template mismatch PCR, the universal primers were designed based on conserved gene coding regions of consensus sequences. The effects of the universal primer-template mismatches on the efficiency of standard PCR amplification were investigated after assembly of sequences from different primers amplifying the same BAC clones. Single or multiple mismatches were observed at 5' terminal, internal and the penultimate position, respectively. These mismatches included the transition mispairs G:T, T:G, A:C and the transversion mispairs A:A, A:G, G:G, G:A. Two or more primer-template mismatches reduced PCR product yield approximately from 2-fold to 10-fold compared to PCR product yield without the primer-template mismatch. For the hemi-nested TD PCR, primers were designed based on the known sequences obtained and/or published. The hemi-nested TD PCR increased both specificity and yield by high and low annealing temperatures in two consecutive amplifications. Comparison of two methods for purifying PCR products prior to sequencing showed that purification using MultiScreen384-PCR filter plates had an advantage over ethanol purification because greater numbers of sequencing reactions could be performed from comparable volumes of PCR reactions. Conclusion This approach was fast, easy and cost-effective for isolation and sequencing of genes from complex gene families. It may be suitable for (i) isolation of other complex gene families and/or gene homologues from BAC libraries, (ii) for characterization of multi-copy repetitive elements pending availability of BAC libraries, and (iii) for filling in gaps in shotgun BAC sequencing. PMID:17480230

  14. A Genome-Wide Association Study of Resistance to Stripe Rust (Puccinia striiformis f. sp. tritici) in a Worldwide Collection of Hexaploid Spring Wheat (Triticum aestivum L.)

    PubMed Central

    Maccaferri, Marco; Zhang, Junli; Bulli, Peter; Abate, Zewdie; Chao, Shiaoman; Cantu, Dario; Bossolini, Eligio; Chen, Xianming; Pumphrey, Michael; Dubcovsky, Jorge

    2015-01-01

    New races of Puccinia striiformis f. sp. tritici (Pst), the causal pathogen of wheat stripe rust, show high virulence to previously deployed resistance genes and are responsible for large yield losses worldwide. To identify new sources of resistance we performed a genome-wide association study (GWAS) using a worldwide collection of 1000 spring wheat accessions. Adult plants were evaluated under field conditions in six environments in the western United States, and seedlings were tested with four Pst races. A single-nucleotide polymorphism (SNP) Infinium 9K-assay provided 4585 SNPs suitable for GWAS. High correlations among environments and high heritabilities were observed for stripe rust infection type and severity. Greater levels of Pst resistance were observed in a subpopulation from Southern Asia than in other groups. GWAS identified 97 loci that were significant for at least three environments, including 10 with an experiment-wise adjusted Bonferroni probability < 0.10. These 10 quantitative trait loci (QTL) explained 15% of the phenotypic variation in infection type, a percentage that increased to 45% when all QTL were considered. Three of these 10 QTL were mapped far from previously identified Pst resistance genes and QTL, and likely represent new resistance loci. The other seven QTL mapped close to known resistance genes and allelism tests will be required to test their relationships. In summary, this study provides an integrated view of stripe rust resistance resources in spring wheat and identifies new resistance loci that will be useful to diversify the current set of resistance genes deployed to control this devastating disease. PMID:25609748

  15. Quantitative Trait Loci and Epistasis for Crown Freezing Tolerance in the ‘Kanota’ × ‘Ogle’ Hexaploid Oat Mapping Population

    Microsoft Academic Search

    David R. Wooten; David P. Livingston; James B. Holland; David S. Marshall; J. Paul Murphy

    2008-01-01

    Crown freezing tolerance is the most important factor conferring oat (Avena spp.) winter hardi- ness. The objective of this study was to identify quantitative trait loci (QTL) for crown freezing tolerance in the 'Kanota' × 'Ogle' recombi- nant inbred line (RIL) mapping population and to examine their relationship with other winter hardiness traits. One hundred thirty-fi ve RILs were evaluated

  16. The Ph1 Locus Suppresses Cdk2-Type Activity during Premeiosis and Meiosis in Wheat W OA

    E-print Network

    Shaw, Peter

    The Ph1 Locus Suppresses Cdk2-Type Activity during Premeiosis and Meiosis in Wheat W OA Emma Greer of related (homoeologous) chromosomes, hexaploid wheat (Triticum aestivum) restricts pairing to just true in hexaploid wheat (Triticum aestivum) and tetraploid wheat (Triticum turgidum) is under the genetic control

  17. A Microsatellite Map of Wheat

    Microsoft Academic Search

    Marion S. Roder; Victor Korzun; Katja Wendehake; Jens Plaschke; Marie-Helene Tixier; Philippe Leroy; Martin W. Ganal

    Hexaploid bread wheat (Triticum aestivum L. em. Thell) is one of the world's most important crop plants and displays a very low level of intraspecific polymorphism. We report the development of highly polymorphic microsatellite markers using procedures optimized for the large wheat genome. The isolation of microsatellite-containing clones from hypomethylated regions of the wheat genome increased the proportion of useful

  18. Bromus species in winter wheat-population dynamics and competitiveness.

    PubMed

    Moray, R; Büchse, A; Hurle, K

    2003-01-01

    The infestation of Bromus species in small grains, especially in winter cereals has increased over recent years. In some areas winter wheat growers consider Bromus spp. as their worst grass weed. Besides yield reduction, Bromus spp. cause lodging and complication of harvest. In Germany the two most dominant species are Bromus sterilis (L.) and Bromus secalinus (L.). In order to develop control strategies the population dynamics of the weeds were investigated. Based on the results a deterministic mathematical model using differential and algebraic equations was used to estimate changes in the population of the two Bromus species. PMID:15149129

  19. Cytogenetically Engineered Rye Chromosomes 1R to Improve Bread-making Quality of Hexaploid Triticale

    Microsoft Academic Search

    Adam J. Lukaszewski

    2006-01-01

    Hexaploid triticale (X Triticosecale Wittmack) is rarely used for human consumption because of its poor bread-making quality. To create the genetic potential for bread-making quality similar to that of bread wheat (Triticum aestivum L), rye (Secale cereale L.) chromo- some 1R in triticale cv. Presto was cytogenetically engineered to remove secalin loci Sec-1 and Sec-3, and to introduce wheat storage

  20. Population-based resequencing analysis of improved wheat germplasm at wheat leaf rust resistance locus Lr21

    Microsoft Academic Search

    Yong-Bi Fu; Gregory W. Peterson; Brent D. McCallum; Li Huang

    2010-01-01

    Little is known about the genetic impacts of modern plant breeding on specific breeding target loci. Resequencing cloned genes\\u000a can identify all mutations in single genes for population-based analyses of genetic changes in improved gene pools. Ninety-five\\u000a wheat cultivars released in Canada from 1845 to 2004 were sequenced at the wheat leaf rust resistance locus Lr21. Characterization of the DNA

  1. Virulence structure of the eastern U.S. wheat powdery mildew population

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Little is known about the population structure of wheat powdery mildew in the eastern 2 U.S., and the most recent report on virulence in this pathogen population involved isolates 3 collected in 1993-94. In the present study, wheat leaves naturally infected with powdery mildew 4 were collected from ...

  2. Niche differentiation between diploid and hexaploid Aster amellus

    Microsoft Academic Search

    Jana Raabová; Markus Fischer; Zuzana Münzbergová

    2008-01-01

    The maintenance of separated diploid and polyploid populations within a contact zone is possible due to both prezygotic and\\u000a postzygotic isolation mechanisms. Niche differentiation between two cytotypes may be an important prezygotic isolating mechanism\\u000a and can be studied using reciprocal transplant experiments. We investigated niche differentiation between diploid and hexaploid\\u000a Aster amellus in their contact zone in the Czech Republic.

  3. In search of tetraploid wheat accessions reduced in celiac disease-related gluten epitopes

    Microsoft Academic Search

    Broeck van den H. C; Chen Hongbing; Xavier Lacaze; Jean-Claude Dusautoir; Ludovicus Gilissen; J. M. Smulders; Meer van der I. M

    2010-01-01

    Tetraploid wheat (durum wheat) is mainly used for the preparation of pasta. As a result of breeding, thousands of tetraploid wheat varieties exist, but also tetraploid landraces are still maintained and used for local food preparations. Gluten proteins present in wheat can induce celiac disease, a T-cell mediated auto-immune disorder, in genetically predisposed individuals after ingestion. Compared to hexaploid wheat,

  4. Molecular mapping of Fusarium head blight resistance in the winter wheat population Dream\\/Lynx

    Microsoft Academic Search

    M. Schmolke; G. Zimmermann; H. Buerstmayr; G. Schweizer; T. Miedaner; V. Korzun; E. Ebmeyer; L. Hartl

    2005-01-01

    Fusarium head blight (FHB), mainly caused by Fusarium graminearum and F. culmorum, can significantly reduce the grain quality of wheat (Triticum aestivum L.) due to mycotoxin contamination. The objective of this study was to identify quantitative trait loci (QTLs) for FHB resistance in a winter wheat population developed by crossing the resistant German cultivar Dream with the susceptible British cultivar

  5. Irrigation Differentially Impacts Populations of Indigenous Antibiotic-Producing Pseudomonas spp. in the Rhizosphere of Wheat

    PubMed Central

    Mavrodi, Olga V.; Mavrodi, Dmitri V.; Parejko, James A.; Thomashow, Linda S.

    2012-01-01

    This work determined the impact of irrigation on the seasonal dynamics of populations of Pseudomonas spp. producing the antibiotics phenazine-1-carboxylic acid (Phz+) and 2,4-diacetylphloroglucinol (Phl+) in the rhizosphere of wheat grown in the low-precipitation zone (150 to 300 mm annually) of the Columbia Plateau of the Inland Pacific Northwest. Population sizes and plant colonization frequencies of Phz+ and Phl+ Pseudomonas spp. were determined in winter and spring wheat collected during the growing seasons from 2008 to 2009 from selected commercial dryland and irrigated fields in central Washington State. Only Phz+ bacteria were detected on dryland winter wheat, with populations ranging from 4.8 to 6.3 log CFU g?1 of root and rhizosphere colonization frequencies of 67 to 100%. The ranges of population densities of Phl+ and Phz+ Pseudomonas spp. recovered from wheat grown under irrigation were similar, but 58 to 100% of root systems were colonized by Phl+ bacteria whereas only 8 to 50% of plants harbored Phz+ bacteria. In addition, Phz+ Pseudomonas spp. were abundant in the rhizosphere of native plant species growing in nonirrigated areas adjacent to the sampled dryland wheat fields. This is the first report that documents the impact of irrigation on indigenous populations of two closely related groups of antibiotic-producing pseudomonads that coinhabit the rhizosphere of an economically important cereal crop. These results demonstrate how crop management practices can influence indigenous populations of antibiotic-producing pseudomonads with the capacity to suppress soilborne diseases of wheat. PMID:22389379

  6. Biotypic diversity in Colorado Russian wheat aphid (Hemiptera: Aphididae) populations.

    PubMed

    Weiland, Aubrey A; Peairs, Frank B; Randolph, Terri L; Rudolph, Jeffrey B; Haley, Scott D; Puterka, Gary J

    2008-04-01

    The biotypic diversity of the Russian wheat aphid, Diuraphis noxia (Kurdjumov) (Hemiptera: Aphididae), was assessed in five isolates collected in Colorado. Three isolates, RWA 1, RWA 2, and an isolate from Montezuma County, CO, designated RWA 6, were originally collected from cultivated wheat, Triticum aestivum L., and obtained from established colonies at Colorado State University. The fourth isolate, designated RWA 7, was collected from Canada wildrye, Elymus canadensis L., in Baca County, CO. The fifth isolate, designated RWA 8, was collected from crested wheatgrass, Agropyron cristatum (L.) Gaertn., in Montezuma County, CO. The four isolates were characterized in a standard seedling assay, by using 24 plant differentials, 22 wheat lines and two barley, Hordeum vulgare L., lines. RWA 1 was the least virulent of the isolates, killing only the four susceptible entries. RWA 8 also killed only the four susceptible entries, but it expressed intermediate virulence on seven wheat lines. RWA 6, killing nine entries, and RWA 7, killing 11 entries, both expressed an intermediate level of virulence overall, but differed in their level of virulence to 'CO03797' (Dn1), 'Yumar' (Dn4), and 'CO960293-2'. RWA 2 was the most virulent isolate, killing 14 entries, including Dn4- and Dny-containing wheat. Four wheat lines, '94M370' (Dn7), 'STARS 02RWA2414-11', CO03797, and 'CI2401', were resistant to the five isolates. The results of this screening confirm the presence of five unique Russian wheat aphid biotypes in Colorado. PMID:18459426

  7. Development of diversity array technology (DArT) markers for assessment of population structure and diversity in Aegilops tauschii

    PubMed Central

    Sohail, Quahir; Shehzad, Tariq; Kilian, Andrezj; Eltayeb, Amin Elsadig; Tanaka, Hiroyuki; Tsujimoto, Hisashi

    2012-01-01

    Aegilops tauschii Coss. is the D-genome donor to hexaploid bread wheat (Triticum aestivum) and is the most promising wild species as a genetic resource for wheat breeding. To study the population structure and diversity of 81 Ae. tauschii accessions collected from various regions of its geographical distribution, the genomic representation of these lines were used to develop a diversity array technology (DArT) marker array. This Ae. tauschii array and a previously developed DArT wheat array were used to scan the genomes of the 81 accessions. Out of 7500 markers (5500 wheat and 2000 Ae. tauschii), 4449 were polymorphic (3776 wheat and 673 Ae. tauschii). Phylogenetic and population structure studies revealed that the accessions could be divided into three groups. The two Ae. tauschii subspecies could also be separately clustered, suggesting that the current taxonomy might be valid. DArT markers are effective to detect very small polymorphisms. The information obtained about Ae. tauschii in the current study could be useful for wheat breeding. In addition, the new DArT array from this Ae. tauschii population is expected to be an effective tool for hexaploid wheat studies. PMID:23136512

  8. GLIADIN ALLELES IN WHEAT: IDENTIFICATION AND APPLICATIONS

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Hexaploid or common bread wheat (2n=42) is a self-pollinated crop, with three genomes designated A, B and D, each composed of seven chromosome pairs. Each Gli locus encodes a group (or block) of gliadin electrophoretic components. Analysis of progenies from crosses between different wheat cultivar...

  9. Fertility of a spontaneous hexaploid male Siberian sturgeon, Acipenser baerii

    PubMed Central

    2014-01-01

    Background Evolution of sturgeons and paddlefishes (order Acipenseriformes) is inherently connected with polyploidization events which resulted in differentiation of ploidy levels and chromosome numbers of present acipenseriform species. Moreover, allopolyploidization as well as autopolyploidization seems to be an ongoing process in these fishes and individuals with abnormal ploidy levels were occasionally observed within sturgeon populations. Here, we reported occurrence of Siberian sturgeon (Acipenser baerii) male with abnormal ploidy level for this species, accessed its ploidy level and chromosome number and investigate its potential sterility or fertility in comparison with normal individuals of sterlet (A. ruthenus), Russian sturgeon (A. gueldenstaedtii) and Siberian sturgeon (A. baerii). Results Acipenser ruthenus possessed 120 chromosomes, exhibiting recent diploidy (2n), A. gueldenstaedtii and A. baerii had ~245 chromosomes representing recent tetraploidy (4n), and A. baerii male with abnormal ploidy level had?~?368 chromosomes, indicating recent hexaploidy (6n). Genealogy assessed from the mtDNA control region did not reveal genome markers of other sturgeon species and this individual was supposed to originate from spontaneous 1.5 fold increment in number of chromosome sets with respect to the number most frequently found in nature for this species. Following hormone stimulation, the spontaneous hexaploid male produced normal sperm with ability for fertilization. Fertilization of A. baerii and A. gueldenstaedtii ova from normal 4n level females with sperm of the hexaploid male produced viable, non-malformed pentaploid (5n) progeny with a ploidy level intermediate to those of the parents. Conclusion This study firstly described occurrence of hexaploid individual of A. baerii and confirmed its autopolyploid origin. In addition to that, the first detailed evidence about fertility of spontaneous hexaploid sturgeon was provided. If 1.5 fold increment in number of chromosome sets occurring in diploids, resulted triploids possess odd number of chromosome sets causing their sterility or subfertility due to interference of gametogenesis. In contrast, 1.5 fold increment in number of chromosome sets in naturally tetraploid A. baerii resulted in even number of chromosome sets and therefore in fertility of the hexaploid specimen under study. PMID:24410899

  10. IMPACT OF IRRIGATION ON POPULATIONS OF ANTIBIOTIC-PRODUCING PSEUDOMONAS SPP. IN RHIZOSPHERE OF WHEAT

    Technology Transfer Automated Retrieval System (TEKTRAN)

    This work studied the impact of irrigation on seasonal dynamics of populations of phenazine (Phz+) and 2,4-diacetylphloroglucinol (Phl+) Pseudomonas spp. in the rhizosphere of wheat grown in the low-precipitation zone (<400 mm) of the Columbia Plateau of the Inland Pacific Northwest, WA. Population...

  11. Structural characterization, expression analysis and evolution of the red\\/far-red sensing photoreceptor gene, phytochrome C ( PHYC ), localized on the ‘B’ genome of hexaploid wheat ( Triticum aestivum L.)

    Microsoft Academic Search

    R. Kulshreshtha; N. Kumar; H. S. Balyan; P. K. Gupta; P. Khurana; A. K. Tyagi; J. P. Khurana

    2005-01-01

    Phytochromes are a family of red\\/far-red light perceiving photoreceptors.The monocot phytochrome family is represented by three members, PHYA, PHYB and PHYC. We have isolated and characterized the first PHY gene member (TaPHYC) from common wheat, Triticum aestivum var. CPAN1676. It codes for a species of the photoreceptor, phyC, which is known to be light-stable in all plants analyzed so far.

  12. Ecogeography, genetic diversity, and breeding value of wild emmer wheat (Triticum dicoccoides Korn ex Asch. & Graebn.) Thell.

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Wild emmer wheat (Triticum dicoccoides Körn ex Asch. & Graebn.) Thell. is the allotetraploid (2n=4x=28; genome BBAA) progenitor of cultivated wheat. It is fully compatible with the tetraploid (BBAA) durum wheat (Triticum durum), and can be crossed with the hexaploid (2n=6x=42; BBAADD) wheat (Triticu...

  13. Inheritance of resistance to Fusarium head blight in three European winter wheat populations.

    PubMed

    Holzapfel, Josef; Voss, Hans-Henning; Miedaner, Thomas; Korzun, Viktor; Häberle, Jennifer; Schweizer, Günther; Mohler, Volker; Zimmermann, Gerhard; Hartl, Lorenz

    2008-11-01

    Fusarium head blight (FHB) resistance is of particular importance in wheat breeding programmes due to the detrimental effects of this fungal disease on human and animal health, yield and grain quality. Segregation for FHB resistance in three European winter wheat populations enabled the identification of resistance loci in well-adapted germplasm. Populations obtained from crosses of resistant cultivars Apache, History and Romanus with susceptible semi-dwarfs Biscay, Rubens and Pirat, respectively, were mapped and analysed to identify quantitative trait loci (QTL) for FHB severity, ear emergence time and plant height. The results of the present study together with previous studies in UK winter wheat indicated that the semi-dwarfing allele Rht-D1b seems to be the major source for FHB susceptibility in European winter wheat. The high resistance level of the cultivars Romanus and History was conditioned by several minor resistance QTL interacting with the environment and the absence of Rht-D1b. In contrast, the semi-dwarf parents contributed resistance alleles of major effects apparently compensating the negative effects of Rht-D1b on FHB reaction. The moderately resistant cultivar Apache contributed a major QTL on chromosome 6A in a genome region previously shown to carry resistance loci to FHB. A total of 18 genomic regions were repeatedly associated with FHB resistance. The results indicate that common resistance-associated genes or genomic regions are present in European winter wheats. PMID:18670751

  14. Irrigation differentially impacts populations of indigenous antibiotic-producing Pseudomonas spp. in the rhizosphere of wheat

    Technology Transfer Automated Retrieval System (TEKTRAN)

    This work determined the impact of irrigation on the seasonal dynamics of populations of Pseudomonas spp. producing the antibiotics phenazine-1-carboxylic acid (Phz+) and 2,4-diacetylphloroglucinol (Phl+) in the rhizosphere of wheat grown in the low precipitation zone (150 to 300 mm annually) of the...

  15. A SNP genotyping array for hexaploid oat

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Recognizing a need in cultivated hexaploid oat (Avena sativa L.) for a reliable set of reference SNPs, we have developed a 6K BeadChip design containing 257 Infinium I and 5,486 Infinium II designs corresponding to 5,743 SNPs. Of those, 4,975 SNPs yielded successful assays after array manufacturing...

  16. Progress toward breeding of waxy (amylose-free) wheats for the Great Plains of North America

    Technology Transfer Automated Retrieval System (TEKTRAN)

    In hexaploid wheats, three independent loci (Wx-A1, Wx-B1 and Wx-D1) encode production of the granule-bound starch synthase (GBSS) also known as the “waxy” protein. Waxy, or amylose-free wheats, have been developed via combination of null mutations at all three loci (Nakamura et al., 1995). Wheat ...

  17. Utilization of deletion bins to anchor and order sequences along the wheat 7B chromosome

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Bread wheat (Triticum aestivum L.) has a large, complex and highly repetitive genome which is challenging to assemble into high quality pseudo-chromosomes. As part of the international effort to sequence the hexaploid bread wheat genome by the international wheat genome sequencing consortium (IWGSC)...

  18. Selecting and Sorting Waxy Wheat Kernels Using Near-Infrared Spectroscopy

    Technology Transfer Automated Retrieval System (TEKTRAN)

    An automated single kernel near-infrared (NIR) sorting system was used to separate single wheat (Triticum aestivum L.) kernels with amylose-free (waxy) starch from reduced-amylose (partial waxy) or wild-type wheat kernels. Waxy kernels of hexaploid wheat are null for the granule-bound starch syntha...

  19. Systematic Spatial Analysis of Gene Expression during Wheat Caryopsis Development W

    E-print Network

    Shaw, Peter

    Systematic Spatial Analysis of Gene Expression during Wheat Caryopsis Development W Sine´ad Drea Centre, Norwich NR4 7UH, United Kingdom b Wheat Improvement Centre, Syngenta, Norwich NR4 7UH, United but coordinated developmental programs. Because of the hexaploid genome in wheat (Triticum aestivum

  20. Population dynamics and within field distribution of the greenbug, Schizaphis graminum (Rondani), and its parasitoids in Central Texas winter wheat 

    E-print Network

    Kring, T. J

    1981-01-01

    POPULATION DYNAMICS AND WITHIN FIELD DISTRIBUTION OF THE GREENBUG, SCHIZAPHIS GRAMINUM (RONDANI), AND ITS PARASITOIDS IN CENTRAL TEXAS WINTER WHEAT A Thesis by TIMOTHY JOSEPH KRING Submitted to the Graduate College of Texas ASM University...

  1. Population Genetic Analysis of an Eastern U.S. Wheat Powdery Mildew Population Reveals Geographic and Recent Common Ancestry with U.K. and Israeli Populations

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The structure of the U.S. wheat powdery mildew population (Blumeria graminis f. sp. tritici) has not been investigated, and the global evolutionary history of B. g. tritici is largely unknown. After gathering 141 single-ascoporic B. g. tritici isolates from 10 eastern U.S. locations, 34 isolates fr...

  2. Physical Mapping Integrated with Syntenic Analysis to Characterize the Gene Space of the Long Arm of Wheat

    E-print Network

    Yanikoglu, Berrin

    of Wheat Chromosome 1A Stuart J. Lucas1,6 , Bala Ani Akpinar1 , Melda Kantar1 , Zohar Weinstein1 , Fatma, Istanbul, Turkey Abstract Background: Bread wheat (Triticum aestivum L.) is one of the most important crops. However, the large, highly repetitive hexaploid wheat genome has been considered intractable to standard

  3. The genetics of rhizosheath size in a multiparent mapping population of wheat.

    PubMed

    Delhaize, Emmanuel; Rathjen, Tina M; Cavanagh, Colin R

    2015-08-01

    Rhizosheaths comprise soil that adheres to plant roots and, in some species, are indicative of root hair length. In this study, the genetics of rhizosheath size in wheat was investigated by screening the progeny of multiparent advanced generation intercrosses (MAGIC). Two MAGIC populations were screened for rhizosheath size using a high throughput method. One MAGIC population was developed from intercrosses between four parents (4-way) and the other from intercrosses between eight parents (8-way). Transgressive segregation for rhizosheath size was observed in both the 4-way and 8-way MAGIC populations. A quantitative trait loci (QTL) analysis of the 4-way population identified six major loci located on chromosomes 2B, 4D, 5A, 5B, 6A, and 7A together accounting for 42% of the variation in rhizosheath size. Rhizosheath size was strongly correlated with root hair length and was robust across different soil types in the absence of chemical constraints. Rhizosheath size in the MAGIC populations was a reliable surrogate for root hair length and, therefore, the QTL identified probably control root hair elongation. Members of the basic helix-loop-helix family of transcription factors have previously been identified to regulate root hair length in Arabidopsis and rice. Since several wheat members of the basic helix-loop-helix family of genes are located within or near the QTL, these genes are candidates for controlling the long root hair trait. The QTL for rhizosheath size identified in this study provides the opportunity to implement marker-assisted selection to increase root hair length for improved phosphate acquisition in wheat. PMID:25969556

  4. Evolution of New Disease Specificity at a Single Resistance Locus in a Crop-Weed Complex: Reconstitution of the Lr21 Gene in Wheat.

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Leaf-rust resistance gene Lr21, present in modern varieties of hexaploid wheat, originated in goatgrass Aegilops tauschii Coss., the D genome donor of wheat. The goatgrass donor was collected in Iran where it grows as a weed in wheat fields as part of the native agricultural ecosystem. In order to ...

  5. Physical mapping of a large plant genome using global high-information-content-fingerprinting: the distal region of the wheat ancestor Aegilops tauschii chromosome 3DS.

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Physical maps employing libraries of bacterial artificial chromosome (BAC) clones are essential for comparative genomics and sequencing of large and repetitive genomes such as those of the hexaploid bread wheat. The diploid ancestor of wheat genome, Aegilops tauschii, is used as a resource for wheat...

  6. The Major Threshability Genes Soft Glume (sog) and Tenacious Glume (Tg), of Diploid and Polyploid Wheat, Trace Their Origin to Independent Mutations at Non-Orthologous Loci

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Threshability is an important crop domestication trait. The wild wheat progenitors have tough glumes enveloping the floret that make spikes difficult to thresh, whereas cultivated wheats have soft glumes and are free-threshing. In hexaploid wheat, the glume tenacity gene Tg along with the major dome...

  7. Transcriptome profiling and expression analyses of genes critical to wheat adaptation to low temperature

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Background: To identify the genes involved in the development of low temperature (LT) tolerance in hexaploid wheat, we examined the global changes in expression in response to cold of the 55,052 potentially unique genes represented in the Affymetrix Wheat Genome microarray. We compared the expressi...

  8. Identification of a novel Fusarium head blight resistance QTL on chromosome 7A in tetraploid wheat

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Fusarium head blight (FHB) caused by Fusarium graminearum is one of the most destructive diseases of durum (Triticum turgidum ssp. durum) and common wheat (T. aestivum). Promising sources of FHB resistance have been identified among common (hexaploid) wheats, but the same is not true for durum (tetr...

  9. Evidence for stable transformation of wheat by floraldip in Agrobacterium tumefaciens

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Hexaploid wheat is one of the world’s most important staple crops but genetic transformation is still challenging. We have developed a floral transformation protocol that does not utilize tissue culture. Three T-DNA wheat transformants have been produced in the germplasm line, Crocus, using this p...

  10. Functionality of Chemically Modified Wild-Type, Partial Waxy and Waxy Starches from Tetraploid Wheats

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Partial waxy (reduced-amylose) and fully waxy (amylose-free) tetraploid wheats (Triticum turgidum L. var durum) were developed by introgression of null alleles at the Wx-A1 and Wx-B1 loci from common hexaploid wheat (T. aestivum L.). Purified starches were obtained from each genotype, and chemicall...

  11. A Comparative Analysis of Free, Bound and Total Lipid Content on Spelt and Winter Wheat Wholemeal

    Microsoft Academic Search

    Nike L. Ruibal-Mendieta; Dominique L. Delacroix; Marc Meurens

    2002-01-01

    Free lipids (FL), bound lipids (BL) and total lipids (TL) were determined by the Soxhlet method in whole ground spelt (Triticum aestivum ssp. spelta L.) and hexaploid winter wheat (T. aestivum) samples. Ninety-one samples of spelt and 78 samples of winter wheat were analysed in the present study. The available material is representative of the wide variability found in spelt

  12. The concurrence of Stagonospora nodorum blotch resistance with host-selective toxin insensitivity in tetraploid wheat

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Resistance to Stagonospora nodorum blotch (SNB) in hexaploid wheat (Triticum aestivum L.) is associated with insensitivity to host-selective toxins (HSTs) produced by the pathogen. In this research, we evaluated the association between HST insensitivity and SNB resistance in tetraploid wheat (T. tur...

  13. Functionality of Native Tetraploid Wheat Starches: Effects of Waxy Loci Alleles and Amylose Concentration in Blends

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Partial waxy (reduced-amylose) and fully waxy (amylose-free) tetraploid durum wheats (Triticum turgidum L. var. durum) were developed by introgression of null alleles at the Wx-A1 and Wx-B1 loci from common hexaploid wheat (T. aestivum L.). These genotypes were used to investigate the relationships...

  14. AB-QTL analysis in winter wheat: II. Genetic analysis of seedling and field resistance against leaf rust in a wheat advanced backcross population

    PubMed Central

    Naz, Ali Ahmad; Kunert, Antje; Lind, Volker; Léon, Jens

    2008-01-01

    The present study aimed to localize exotic quantitative trait locus (QTL) alleles for the improvement of leaf rust (P.triticina) resistance in an advanced backcross (AB) population, B22, which is derived from a cross between the winter wheat cultivar Batis (Triticumaestivum) and the synthetic wheat accession Syn022L. The latter was developed from hybridization of T.turgidum ssp. dicoccoides and T.tauschii. Altogether, 250 BC2F3 lines of B22 were assessed for seedling resistance against the leaf rust isolate 77WxR under controlled conditions. In addition, field resistance against leaf rust was evaluated by assessing symptom severity under natural infestation across multiple environments. Simultaneously, population B22 was genotyped with a total of 97 SSR markers, distributed over the wheat A, B and D genomes. The phenotype and genotype data were subjected to QTL analysis by applying a 3-factorial mixed model analysis of variance including the marker genotype as a fixed effect and the environments, the lines and the marker by environment interactions as random effects. The QTL analysis revealed six putative QTLs for seedling resistance and seven for field resistance. For seedling resistance, the effects of exotic QTL alleles improved resistance at all detected loci. The maximum decrease of disease symptoms (?46.3%) was associated with marker locus Xbarc149 on chromosome 1D. For field resistance, two loci had stable main effects across environments and five loci exhibited marker by environment interaction effects. The strongest effects were detected at marker locus Xbarc149 on chromosome 1D, at which the exotic allele decreased seedling symptoms by 46.3% and field symptoms by 43.6%, respectively. Some of the detected QTLs co-localized with known resistance genes, while others appear to be as novel resistance loci. Our findings indicate, that the exotic wheat accession Syn022L may be useful for the improvement of leaf rust resistance in cultivated wheat. PMID:18338154

  15. Characterization of Ferredoxin-Dependent Glutamine-Oxoglutarate Amidotransferase (Fd-GOGAT) Genes and Their Relationship with Grain Protein Content QTL in Wheat

    PubMed Central

    2014-01-01

    Background In higher plants, inorganic nitrogen is assimilated via the glutamate synthase cycle or GS-GOGAT pathway. GOGAT enzyme occurs in two distinct forms that use NADH (NADH-GOGAT) or Fd (Fd-GOGAT) as electron carriers. The goal of the present study was to characterize wheat Fd-GOGAT genes and to assess the linkage with grain protein content (GPC), an important quantitative trait controlled by multiple genes. Results We report the complete genomic sequences of the three homoeologous A, B and D Fd-GOGAT genes from hexaploid wheat (Triticum aestivum) and their localization and characterization. The gene is comprised of 33 exons and 32 introns for all the three homoeologues genes. The three genes show the same exon/intron number and size, with the only exception of a series of indels in intronic regions. The partial sequence of the Fd-GOGAT gene located on A genome was determined in two durum wheat (Triticum turgidum ssp. durum) cvs Ciccio and Svevo, characterized by different grain protein content. Genomic differences allowed the gene mapping in the centromeric region of chromosome 2A. QTL analysis was conducted in the Svevo×Ciccio RIL mapping population, previously evaluated in 5 different environments. The study co-localized the Fd-GOGAT-A gene with the marker GWM-339, identifying a significant major QTL for GPC. Conclusions The wheat Fd-GOGAT genes are highly conserved; both among the three homoeologous hexaploid wheat genes and in comparison with other plants. In durum wheat, an association was shown between the Fd-GOGAT allele of cv Svevo with increasing GPC - potentially useful in breeding programs. PMID:25099972

  16. Map-based analysis of the tenacious glume gene Tg-B1 of wild emmer and its role in wheat domestication.

    PubMed

    Faris, Justin D; Zhang, Zengcui; Chao, Shiaoman

    2014-06-01

    The domestication of wheat was instrumental in spawning the civilization of humankind, and it occurred through genetic mutations that gave rise to types with non-fragile rachises, soft glumes, and free-threshing seed. Wild emmer (Triticum turgidum ssp. dicoccoides), the tetraploid AB-genome progenitor of domesticated wheat has genes that confer tenacious glumes (Tg) that underwent genetic mutations to give rise to free-threshing wheat. Here, we evaluated disomic substitution lines involving chromosomes 2A and 2B of wild emmer accessions substituted for homologous chromosomes in tetraploid and hexaploid backgrounds. The results suggested that both chromosomes 2A and 2B of wild emmer possess genes that inhibit threshability. A population of recombinant inbred lines derived from the tetraploid durum wheat variety Langdon crossed with a Langdon - T. turgidum ssp. dicoccoides accession PI 481521 chromosome 2B disomic substitution line was used to develop a genetic linkage map of 2B, evaluate the genetics of threshability, and map the gene derived from PI 481521 that inhibited threshability. A 2BS linkage map comprised of 58 markers was developed, and markers delineated the gene to a 2.3 cM interval. Comparative analysis with maps containing the tenacious glume gene Tg-D1 on chromosome arm 2 DS from Aegilops tauschii, the D genome progenitor of hexaploid wheat, revealed that the gene inhibiting threshability in wild emmer was homoeologous to Tg-D1 and therefore designated Tg-B1. Comparative analysis with rice and Brachypodium distachyon indicated a high level of divergence and poorly conserved colinearity, particularly near the Tg-B1 locus. These results provide a foundation for further studies involving Tg-B1, which, together with Tg-D1, had profound influences on wheat domestication. PMID:24657062

  17. Chromosomal Behavior during Meiosis in the Progeny of Triticum timopheevii × Hexaploid Wild Oat.

    PubMed

    An, Hongzhou; Hu, Mei; Li, Pengfei; Geng, Guangdong; Zhang, Qingqin; Zhang, Suqin

    2015-01-01

    The meiotic behavior of pollen mother cells (PMCs) of the F2 and F3 progeny from Triticum timopheevii × hexaploid wild oat was investigated by cytological analysis and sequential C-banding-genomic in situ hybridization (GISH) in the present study. A cytological analysis showed that the chromosome numbers of the F2 and F3 progeny ranged from 28 to 41. A large number of univalents, lagging chromosomes, chromosome bridges and micronuclei were found at the metaphase I, anaphase I, anaphase II and tetrad stages in the F2 and F3 progeny. The averages of univalents were 3.50 and 2.73 per cell, and those of lagging chromosomes were 3.37 and 1.87 in the F2 and F3 progeny, respectively. The PMC meiotic indices of the F2 and F3 progeny were 12.22 and 20.34, respectively, indicating considerable genetic instability. A sequential C-banding-GISH analysis revealed that some chromosomes and fragments from the hexaploid wild oat were detected at metaphase I and anaphase I in the progeny, showing that the progeny were of true intergeneric hybrid origin. The alien chromosomes 6A, 7A, 3C and 2D were lost during transmission from F2 to F3. In addition, partial T. timopheevii chromosomes appeared in the form of univalents or lagging chromosomes, which might result from large genome differences between the parents, and the wild oat chromosome introgression interfered with the wheat homologues' normally pairing. PMID:25950431

  18. Genetic Relationships, Carbendazim Sensitivity and Mycotoxin Production of the Fusarium Graminearum Populations from Maize, Wheat and Rice in Eastern China

    PubMed Central

    Qiu, Jianbo; Shi, Jianrong

    2014-01-01

    Members of the Fusarium graminearum species complex (FGSC) are important pathogens on wheat, maize, barley, and rice in China. Harvested grains are often contaminated by mycotoxins, such as the trichothecene nivalenol (NIV) and deoxynivalenol (DON) and the estrogenic mycotoxin zearalenone (ZEN), which is a big threat to humans and animals. In this study, 97 isolates were collected from maize, wheat, and rice in Jiangsu and Anhui provinces in 2013 and characterized by species- and chemotype-specific PCR. F. graminearum sensu stricto (s. str.) was predominant on maize, while most of the isolates collected from rice and wheat were identified as F. asiaticum. Fusarium isolates from three hosts varied in trichothecene chemotypes. The 3-acetyldeoxynivalenol (3ADON) chemotype predominated on wheat and rice population, while 15ADON was prevailing in the remaining isolates. Sequence analysis of the translation elongation factor 1? and trichodiene synthase indicated the accuracy of the above conclusion. Additionally, phylogenetic analysis suggested four groups with strong correlation with species, chemotype, and host. These isolates were also evaluated for their sensitivity to carbendazim and mycotoxins production. The maize population was less sensitive than the other two. The DON levels were similar in three populations, while those isolates on maize produced more ZEN. More DON was produced in carbendazim resistant strains than sensitive ones, but it seemed that carbendazim resistance had no effect on ZEN production in wheat culture. PMID:25093387

  19. Natural Lactic Acid Bacteria Population and Silage Fermentation of Whole-crop Wheat.

    PubMed

    Ni, Kuikui; Wang, Yanping; Cai, Yimin; Pang, Huili

    2015-08-01

    Winter wheat is a suitable crop to be ensiled for animal feed and China has the largest planting area of this crop in the world. During the ensiling process, lactic acid bacteria (LAB) play the most important role in the fermentation. We investigated the natural population of LAB in whole-crop wheat (WCW) and examined the quality of whole-crop wheat silage (WCWS) with and without LAB inoculants. Two Lactobacillus plantarum subsp. plantarum strains, Zhengzhou University 1 (ZZU 1) selected from corn and forage and grass 1 (FG 1) from a commercial inoculant, were used as additives. The silages inoculated with LAB strains (ZZU 1 and FG 1) were better preserved than the control, with lower pH values (3.5 and 3.6, respectively) (p<0.05) and higher contents of lactic acid (37.5 and 34.0 g/kg of fresh matter (FM), respectively) (p<0.05) than the control. Sixty LAB strains were isolated from fresh material and WCWS without any LAB inoculation. These LAB strains were divided into the following four genera and six species based on their phenotypic, biochemical and phylogenetic characteristics: Leuconostoc pseudomesenteroides, Leuconostoc citreum, Weissella cibaria, Lactococcus lactis subsp. lactis, Lactobacillus buchneri, and Lactobacillus plantarum subsp. plantarum. However, the prevalent LAB, which was predominantly heterofermentative (66.7%), consisted of Leuconostoc pseudomesenteroides, Leuconostoc citreum, Weissella cibaria, and Lactobacillus buchneri. This study revealed that most of isolated LAB strains from control WCWS were heterofermentative and could not grow well at low pH condition; the selective inoculants of Lactobacillus strains, especially ZZU 1, could improve WCWS quality significantly. PMID:26104520

  20. Evolutionary Genomics of Wheat

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Wheat is the world’s largest and most important food crop for direct human consumption, therefore, continued wheat improvement is paramount for feeding an ever-increasing human population. Wheat improvement is tightly associated with the characterization and understanding of wheat evolution and gene...

  1. Quantitative trait loci for adult-plant resistance to Mycosphaerella graminicola in two winter wheat populations.

    PubMed

    Risser, P; Ebmeyer, E; Korzun, V; Hartl, L; Miedaner, T

    2011-10-01

    Septoria tritici blotch (STB) is one of the most important leaf spot diseases in wheat worldwide. The goal of this study was to detect chromosomal regions for adult-plant resistance in large winter wheat populations to STB. Inoculation by two isolates with virulence to Stb6 and Stb15, both present in the parents, was performed and STB severity was visually scored plotwise as percent coverage of flag leaves with pycnidia-bearing lesions. 'Florett'/'Biscay' and 'Tuareg'/'Biscay', each comprising a cross of a resistant and a susceptible cultivar, with population sizes of 316 and 269 F(7:8) recombinant inbred lines, respectively, were phenotyped across four and five environments and mapped with amplified fragment length polymorphism, diversity array technology, and simple sequence repeat markers covering polymorphic regions of ?1,340 centimorgans. Phenotypic data revealed significant (P < 0.01) genotypic differentiation for STB, heading date, and plant height. Entry-mean heritabilities (h(2)) for STB were 0.73 for 'Florett'/'Biscay' and 0.38 for 'Tuareg'/'Biscay'. All correlations between STB and heading date as well as between STB and plant height were low (r = -0.13 to -0.20). In quantitative trait loci (QTL) analysis, nine and six QTL were found for STB ratings explaining, together, 55 and 51% of phenotypic variation in 'Florett'/'Biscay' and 'Tuareg'/'Biscay', respectively. Genotype-environment and QTL-environment interactions had a large impact. Two major QTL were detected consistently across environments on chromosomes 3B and 6D from 'Florett' and chromosomes 4B and 6B from 'Tuareg', each explaining 12 to 17% of normalized adjusted phenotypic variance. These results indicate that adult-plant resistance to STB in both mapping populations was of a quantitative nature. PMID:21635143

  2. The emerging biofuel crop Camelina sativa retains a highly undifferentiated hexaploid genome structure

    PubMed Central

    Kagale, Sateesh; Koh, Chushin; Nixon, John; Bollina, Venkatesh; Clarke, Wayne E.; Tuteja, Reetu; Spillane, Charles; Robinson, Stephen J.; Links, Matthew G.; Clarke, Carling; Higgins, Erin E.; Huebert, Terry; Sharpe, Andrew G.; Parkin, Isobel A. P.

    2014-01-01

    Camelina sativa is an oilseed with desirable agronomic and oil-quality attributes for a viable industrial oil platform crop. Here we generate the first chromosome-scale high-quality reference genome sequence for C. sativa and annotated 89,418 protein-coding genes, representing a whole-genome triplication event relative to the crucifer model Arabidopsis thaliana. C. sativa represents the first crop species to be sequenced from lineage I of the Brassicaceae. The well-preserved hexaploid genome structure of C. sativa surprisingly mirrors those of economically important amphidiploid Brassica crop species from lineage II as well as wheat and cotton. The three genomes of C. sativa show no evidence of fractionation bias and limited expression-level bias, both characteristics commonly associated with polyploid evolution. The highly undifferentiated polyploid genome of C. sativa presents significant consequences for breeding and genetic manipulation of this industrial oil crop. PMID:24759634

  3. The emerging biofuel crop Camelina sativa retains a highly undifferentiated hexaploid genome structure.

    PubMed

    Kagale, Sateesh; Koh, Chushin; Nixon, John; Bollina, Venkatesh; Clarke, Wayne E; Tuteja, Reetu; Spillane, Charles; Robinson, Stephen J; Links, Matthew G; Clarke, Carling; Higgins, Erin E; Huebert, Terry; Sharpe, Andrew G; Parkin, Isobel A P

    2014-01-01

    Camelina sativa is an oilseed with desirable agronomic and oil-quality attributes for a viable industrial oil platform crop. Here we generate the first chromosome-scale high-quality reference genome sequence for C. sativa and annotated 89,418 protein-coding genes, representing a whole-genome triplication event relative to the crucifer model Arabidopsis thaliana. C. sativa represents the first crop species to be sequenced from lineage I of the Brassicaceae. The well-preserved hexaploid genome structure of C. sativa surprisingly mirrors those of economically important amphidiploid Brassica crop species from lineage II as well as wheat and cotton. The three genomes of C. sativa show no evidence of fractionation bias and limited expression-level bias, both characteristics commonly associated with polyploid evolution. The highly undifferentiated polyploid genome of C. sativa presents significant consequences for breeding and genetic manipulation of this industrial oil crop. PMID:24759634

  4. Use of a large multiparent wheat mapping population in genomic dissection of coleoptile and seedling growth.

    PubMed

    Rebetzke, Greg J; Verbyla, Arunas P; Verbyla, Klara L; Morell, Matthew K; Cavanagh, Colin R

    2014-02-01

    Identification of alleles towards the selection for improved seedling vigour is a key objective of many wheat breeding programmes. A multiparent advanced generation intercross (MAGIC) population developed from four commercial spring wheat cultivars (cvv. Baxter, Chara, Westonia and Yitpi) and containing ca. 1000 F(2) -derived, F(6:7) RILs was assessed at two contrasting soil temperatures (12 and 20 °C) for shoot length and coleoptile characteristics length and thickness. Narrow-sense heritabilities were high for coleoptile and shoot length (h(2) = 0.68-0.70), indicating a strong genetic basis for the differences among progeny. Genotypic variation was large, and distributions of genotype means were approximately Gaussian with evidence for transgressive segregation for all traits. A number of significant QTL were identified for all early growth traits, and these were commonly repeatable across the different soil temperatures. The largest negative effects on coleoptile lengths were associated with Rht-B1b (-8.2%) and Rht-D1b (-10.9%) dwarfing genes varying in the population. Reduction in coleoptile length with either gene was particularly large at the warmer soil temperature. Other large QTL for coleoptile length were identified on chromosomes 1A, 2B, 4A, 5A and 6B, but these were relatively smaller than allelic effects at the Rht-B1 and Rht-D1 loci. A large coleoptile length effect allele (a = 5.3 mm at 12 °C) was identified on chromosome 1AS despite the relatively shorter coleoptile length of the donor Yitpi. Strong, positive genetic correlations for coleoptile and shoot lengths (r(g) = 0.85-0.90) support the co-location of QTL for these traits and suggest a common physiological basis for both. The multiparent population has enabled the identification of promising shoot and coleoptile QTL despite the potential for the confounding of large effect dwarfing gene alleles present in the commercial parents. The incidence of these alleles in commercial wheat breeding programmes should facilitate their ready implementation in selection of varieties with improved establishment and early growth. PMID:24151921

  5. Nivalenol-type populations of Fusarium graminearum and F. asiaticum are prevalent on wheat in Southern Louisiana

    Technology Transfer Automated Retrieval System (TEKTRAN)

    U.S. populations of the Fusarium graminearum (Fg) clade cause Fusarium head blight (FHB) on wheat and barley and usually produce the trichothecene mycotoxin deoxynivalenol in infected grain. Recently, however, individual nivalenol (NIV)-producing isolates from the U.S. were described, that belonged ...

  6. POPULATIONS OF 2,4-DIACETYLPHLOROGLUCINOL (DAPG)-PRODUCING PSEUDOMONAS FLUORESCENS IN THE RHIZOSPHERE OF PYTHIUM-INFECTED WHEAT

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Root infections by soilborne pathogens can either positively or negatively affect root colonization and antibiotic production by beneficial bacteria. We tested the impact of four Pythium spp. on colonization of wheat roots by indigenous populations of 2,4-diacetylphloroglucinol (DAPG)-producing Pse...

  7. POPULATION DYNAMICS IN THE FIELD OF A BIOCONTROL AGENT FOR FUSARIUM HEAD BLIGHT OF WHEAT

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Gibberella zeae (anamorph Fusarium graminearum) is the major causal organism of Fusarium head blight (FHB) on wheat and barley. Wheat anthers are an important site of infection. Application of Crytococcus nodaensis OH 182.9 to wheat heads at the time of flowering reduces FHB. The goal of this res...

  8. POPULATION GENETICS OF THE WHEAT LEAF RUST FUNGUS, PUCCINIA TRITICINA IN CENTRAL ASIA

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Wheat leaf rust, caused by Puccinia triticina, is a major disease of wheat in Central Asia. Single uredinial isolates from Armenia, Azerbaijan, Tajikistan, Kazakhstan, Uzbekistan, and Kyrgyzstan, 131 in total, were tested for virulence to 20 isolines of Thatcher wheat with single leaf rust resistanc...

  9. Identification and molecular mapping of a resistance gene to powdery mildew from the synthetic wheat line M53

    Microsoft Academic Search

    Tao Li; Zengyan Zhang; Yingkao Hu; Xiayu Duan; Zhiyong Xin

    2011-01-01

    Powdery mildew disease caused by Blumeria graminis f. sp. tritici (Bgt) is an economically important disease in wheat worldwide. The identification of germplasms resistant to the disease can not only facilitate the breeding of resistant cultivars, but can also broaden the diversity of resistance genes. The Mexican M53 is a synthetic hexaploid wheat line developed at the Interna- tional Maize

  10. GENETIC CHARACTERIZATION AND MOLECULAR MAPPING OF HESSIAN FLY RESISTANCE GENES DERIVED FROM TRITICUM TAUSCHII IN SYNTHETIC WHEAT

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Two synthetic hexaploid wheat lines (×Aegilotriticum spp., 2n=6x=42, genomes AABBDD), SW8 and SW34, developed from the crosses of the durum wheat cultivar Langdon (Triticum turgidum L. var. durum, 2n=4x=28, genomes AABB) with two T. tauschii (Coss.) Schmal accessions (2n=2x=14, genome DD), were dete...

  11. Rye-derived powdery mildew resistance gene Pm8 in wheat is suppressed by the Pm3 locus

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Genetic suppression of disease resistance is occasionally observed in hexaploid wheat or in its interspecific crosses. The phenotypic effects of genes moved to wheat from relatives with lower ploidy are often smaller than in the original sources, suggesting the presence of modifiers or partial inhib...

  12. Fifty new microsatellite loci for the wheat genetic map

    Microsoft Academic Search

    P. Stephenson; G. Bryan; J. Kirby; A. Collins; K. Devos; C. Busso; M. Gale

    1998-01-01

    Hexaploid bread wheat (Triticum aestivum) has low levels of RFLP. Simple sequence repeats, however, show high levels of polymorphism and are therefore especially\\u000a useful in intervarietal breeding applications. We present 53 newly mapped microsatellite loci for the wheat genetic map, 41\\u000a primary loci and 12 additional loci from these same primer pairs. Markers have been accredited with a quality score

  13. Genetic Diversity and Population Structure of Tetraploid Wheats (Triticum turgidum L.) Estimated by SSR, DArT and Pedigree Data

    PubMed Central

    Laidò, Giovanni; Mangini, Giacomo; Taranto, Francesca; Gadaleta, Agata; Blanco, Antonio; Cattivelli, Luigi; Marone, Daniela; Mastrangelo, Anna M.; Papa, Roberto; De Vita, Pasquale

    2013-01-01

    Levels of genetic diversity and population genetic structure of a collection of 230 accessions of seven tetraploid Triticum turgidum L. subspecies were investigated using six morphological, nine seed storage protein loci, 26 SSRs and 970 DArT markers. The genetic diversity of the morphological traits and seed storage proteins was always lower in the durum wheat compared to the wild and domesticated emmer. Using Bayesian clustering (K?=?2), both of the sets of molecular markers distinguished the durum wheat cultivars from the other tetraploid subspecies, and two distinct subgroups were detected within the durum wheat subspecies, which is in agreement with their origin and year of release. The genetic diversity of morphological traits and seed storage proteins was always lower in the improved durum cultivars registered after 1990, than in the intermediate and older ones. This marked effect on diversity was not observed for molecular markers, where there was only a weak reduction. At K >2, the SSR markers showed a greater degree of resolution than for DArT, with their identification of a greater number of groups within each subspecies. Analysis of DArT marker differentiation between the wheat subspecies indicated outlier loci that are potentially linked to genes controlling some important agronomic traits. Among the 211 loci identified under selection, 109 markers were recently mapped, and some of these markers were clustered into specific regions on chromosome arms 2BL, 3BS and 4AL, where several genes/quantitative trait loci (QTLs) are involved in the domestication of tetraploid wheats, such as the tenacious glumes (Tg) and brittle rachis (Br) characteristics. On the basis of these results, it can be assumed that the population structure of the tetraploid wheat collection partially reflects the evolutionary history of Triticum turgidum L. subspecies and the genetic potential of landraces and wild accessions for the detection of unexplored alleles. PMID:23826256

  14. Sequence Polymorphism in Polyploid Wheat and Their D-Genome Diploid Ancestor

    Microsoft Academic Search

    Katherine S. Caldwell; Jan Dvorak; Evans S. Lagudah; Eduard Akhunov; Ming-Cheng Luo; Petra Wolters; Wayne Powell

    2004-01-01

    Sequencing was used to investigate the origin of the D genome of the allopolyploid species Triticum aestivum and Aegilops cylindrica. A 247-bp region of the wheat D-genome Xwye838 locus, encoding ADP- glucopyrophosphorylase, and a 326-bp region of the wheat D-genome Gss locus, encoding granule-bound starch synthase, were sequenced in a total 564 lines of hexaploid wheat (T. aestivum, genome AABBDD)

  15. NAD-dependent aromatic alcohol dehydrogenase in wheats ( Triticum L.) and goatgrasses ( Aegilops L.): evolutionary genetics

    Microsoft Academic Search

    Vello Jaaska

    1984-01-01

    Evolutionary electrophoretic variation of a NAD-specific aromatic alcohol dehydrogenase, AADH-E, in wheat and goatgrass species is described and discussed in comparison with a NAD-specific alcohol dehydrogenase (ADH-A) and a NADP-dependent AADH-B studied previously. Cultivated tetraploid emmer wheats (T. turgidum s. l.) and hexaploid bread wheats (T. aestivum s. l.) are all fixed for a heterozygous triplet, E0.58\\/E0.64. The slowest isoenzyme,

  16. The cytological and genetic characterisation of doubled haploid lines derived from triticale×wheat hybrids

    Microsoft Academic Search

    Y. Z. Tao; J. W. Snape; H. Hu

    1991-01-01

    Anther culture, when applied to hexaploid triticale×wheat hybrids, offers the opportunity to re-assort wheat D genome and rye R genome chromosomes into homozygous doubled haploid lines in a single generation. The characterisation of such lines is the first step in their utilisation in wheat improvement. Two lines, M24 and M25 from the cross of ‘Beagle’בKedong 58’, and one line, M27,

  17. Development of simple sequence repeat markers specific for the Lr34 resistance region of wheat using sequence information from rice and Aegilops tauschii

    Microsoft Academic Search

    Eligio Bossolini; Simon G. Krattinger; Beat Keller

    2006-01-01

    Hexaploid wheat (Triticum aestivum L.) originated about 8,000 years ago from the hybridization of tetraploid wheat with diploid Aegilops tauschii Coss. containing the D-genome. Thus, the bread wheat D-genome is evolutionary young and shows a low degree of polymorphism in the bread wheat gene pool. To increase marker density around the durable leaf rust resistance gene Lr34 located on chromosome 7DS,

  18. QTL mapping of stripe, leaf and stem rust resistance genes in a Kariega × Avocet S doubled haploid wheat population

    Microsoft Academic Search

    R. Prins; Z. A. Pretorius; C. M. Bender; A. Lehmensiek

    2011-01-01

    Adult plant resistance to stripe (yellow) rust in the wheat cultivar Kariega has previously been ascribed to a major quantitative\\u000a trait locus (QTL) on each of chromosomes 2B and 7D, along with a number of minor QTL. We have extended both the size of the\\u000a cv. Kariega × cv. Avocet S mapping population, and the marker coverage within it, by assembling a

  19. Weed populations and agronomic practices at wheat farms on the Hanang plains in Tanzania

    Microsoft Academic Search

    J. R. Moyer; Z. J. Owenya; S. P. Kibuwa

    1989-01-01

    Weed species and densities of weeds present on the wheat farms at the Hanang plains in northern Tanzania were surveyed just before wheat harvest in May, 1986. The dominant weed was Setaria spp. mainly, Setaria verticillata (L.) Beauv., which occurred at an average density of 58 shoots\\/m. Additional weed species which occurred at average densities of greater than 1 plant\\/m

  20. Variation among hexaploid Paspalum dilatum Poir. regenerants from tissue culture.

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The common biotype of Paspalum dilatatum, called paspalum in Australia and dallisgrass in the U.S.A., is a pentaploid obligate apomict and efforts to improve the grass have not been successful because of its asexual reproduction and irregular meiosis. An apomictic hexaploid biotype, known as Urugua...

  1. Chromosome-anchored QTL conferring aluminum tolerance in hexaploid oat

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Abstract Aluminum (Al) toxicity is a major constraint on crop production in acid soils around the world. Hexaploid oat (Avena sativa L.) possesses signi'cant Al tolerance making it a good candidate for production in these environments. Genetic improvement for Al tolerance in oat has traditionally be...

  2. Uredospore germination and germ tube penetration of Puccinia striiformis in seedling leaves of resistant and susceptible wheat varieties

    Microsoft Academic Search

    R. W. Stubbs; J. M. Plotnikova

    1972-01-01

    Differences were observed in spore germination and germ tube penetration of race 60 ofPuccinia striiformis on some wheat varieties. Of the five wheat varieties investigatedTriticum spelta var.album was the most resistant, strongly inhibiting spore germination and retarding germ tube penetration. On the hexaploid wheat varieties the germ tube penetrated through the stomata, whereas on the tetraploid varieties it did so

  3. The effect of wheat prebiotics on the gut bacterial population and iron status of iron deficient broiler chickens

    PubMed Central

    2014-01-01

    Background Currently, there is a lot of interest in improving gut health, and consequently increasing Fe absorption, by managing the colonic microbial population. This is traditionally done by the consumption of probiotics, live microbial food supplements. However, an alternative, and often very effective approach, is the consumption of food ingredients known as prebiotics. Fructans and arabinoxylans are naturally occurring non-digestible oligosaccharides in wheat that exhibit prebiotic properties and may enhance intestinal iron (Fe) absorption. The aim of this study was to assess the effect of prebiotics from wheat on Fe bioavailability in vitro (Caco-2 cells) and in vivo (broiler chickens, Gallus gallus). Methods In the current study, the effect of intra-amniotic administration of wheat samples extracts at 17 d of embryonic incubation on the Fe status and possible changes in the bacterial population in intestinal content of broiler hatchlings were investigated. A group of 144 eggs were injected with the specified solution (1 ml per egg) into the amniotic fluid. Immediately after hatch (21 d) and from each treatment group, 10 chicks were euthanized and their small intestine, liver and cecum were removed for relative mRNA abundance of intestinal Fe related transporters, relative liver ferritin amounts and bacterial analysis of cecal content, respectively. Results The in vivo results are in agreement with the in vitro observations, showing no differences in the hatchling Fe status between the treatment groups, as Fe bioavailability was not increased in vitro and no significant differences were measured in the intestinal expression of DMT1, Ferroportin and DcytB in vivo. However, there was significant variation in relative amounts of bifidobacteria and lactobacilli in the intestinal content between the treatments groups, with generally more bifidobacteria being produced with increased prebiotic content. Conclusions In this study we showed that prebiotics naturally found in wheat grains/bread products significantly increased intestinal beneficial bacterial population in Fe deficient broiler chickens. With this short-term feeding trial we were not able to show differences in the Fe-status of broilers. Nevertheless, the increase in relative amounts of bifidobacteria and lactobacilli in the presence of wheat prebiotics is an important finding as these bacterial populations may affect Fe bioavailability in long-term studies. PMID:24924421

  4. SINGLE KERNEL NEAR-INFRARED ANALYSIS OF TETRAPLOID (DURUM) WHEAT FOR CLASSIFICATION OF THE WAXY CONDITION

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Plant breeding programs are currently active worldwide in the development of waxy hexaploid (bread) and tetraploid (pasta) wheats. It is generally believed that by means of conventional breeding practices, waxy cultivars, adapted to their intended geographical region will confer unique processing a...

  5. High-Quality Draft Genome Sequence of Pseudomonas syringae pv. Syringae Strain SM, Isolated from Wheat

    PubMed Central

    Dudnik, Alexey

    2013-01-01

    Pseudomonas syringae is one of the most widespread plant pathogens that can cause significant damage to crop plantations. Here, we announce a noncontiguous finished genome sequence of Pseudomonas syringae pv. syringae strain SM, isolated from hexaploid wheat. The genome sequence revealed the smallest described complement of type III effectors. PMID:23950121

  6. BAC-FISH in wheat identifies chromosome landmarks consisting of different types of transposable elements

    Microsoft Academic Search

    Peng Zhang; Wanlong Li; John Fellers; Bernd Friebe; Bikram S. Gill

    2004-01-01

    Fluorescence in situ hybridization (FISH) has been widely used in the physical mapping of genes and chromosome landmarks in plants and animals. Bacterial artificial chromosomes (BACs) contain large inserts making them amenable for FISH mapping. We used BAC-FISH to study genome organization and evolution in hexaploid wheat and its relatives. We selected 56 restriction fragment length polymorphism (RFLP) locus-specific BAC

  7. Bread making quality attributes of Iranian trade cultivars of wheat and their HMW glutenin subunits composition

    Microsoft Academic Search

    Najafian G; Baghaee N; Morteza-gholi M; Babaee-Goli E

    Sixty seven varieties of wheat including mostly hexaploid and durum genotypes grown in Iran were tested for bread making quality attributes and their hectoliter weight, percentage of protein content, grain hardness index, flour water absorption, falling number and SDS-sedimentation volume were determined. High molecular weight (HMW) glutenin subunits composition of these varieties was also determined using SDS- PAGE. Clustering of

  8. Development of simple sequence repeat markers specific for the Lr34 resistance region of wheat using sequence information from rice and Aegilops tauschii.

    PubMed

    Bossolini, Eligio; Krattinger, Simon G; Keller, Beat

    2006-10-01

    Hexaploid wheat (Triticum aestivum L.) originated about 8,000 years ago from the hybridization of tetraploid wheat with diploid Aegilops tauschii Coss. containing the D-genome. Thus, the bread wheat D-genome is evolutionary young and shows a low degree of polymorphism in the bread wheat gene pool. To increase marker density around the durable leaf rust resistance gene Lr34 located on chromosome 7DS, we used molecular information from the orthologous region in rice. Wheat expressed sequence tags (wESTs) were identified by homology with the rice genes in the interval of interest, but were monomorphic in the 'Arina' x 'Forno' mapping population. To derive new polymorphic markers, bacterial artificial chromosome (BAC) clones representing a total physical size of approximately 1 Mb and belonging to four contigs were isolated from Ae. tauschii by hybridization screening with wheat ESTs. Several BAC clones were low-pass sequenced, resulting in a total of approximately 560 kb of sequence. Ten microsatellite sequences were found, and three of them were polymorphic in our population and were genetically mapped close to Lr34. Comparative analysis of marker order revealed a large inversion between the rice genome and the wheat D-genome. The SWM10 microsatellite is closely linked to Lr34 and has the same allele in the three independent sources of Lr34: 'Frontana', 'Chinese Spring', and 'Forno', as well in most of the genotypes containing Lr34. Therefore, SWM10 is a highly useful marker to assist selection for Lr34 in breeding programs worldwide. PMID:16896711

  9. Assessment of Allergy to Milk, Egg, Cod, and Wheat in Swedish Schoolchildren: A Population Based Cohort Study

    PubMed Central

    Winberg, Anna; West, Christina E; Strinnholm, Åsa; Nordström, Lisbeth; Hedman, Linnea; Rönmark, Eva

    2015-01-01

    Objectives Knowledge about the prevalence of allergies to foods in childhood and adolescence is incomplete. The purpose of this study was to investigate the prevalence of allergies to milk, egg, cod, and wheat using reported data, clinical examinations, and double-blind placebo-controlled food challenges, and to describe the phenotypes of reported food hypersensitivity in a cohort of Swedish schoolchildren. Methods In a population-based cohort of 12-year-old children, the parents of 2612 (96% of invited) completed a questionnaire. Specific IgE antibodies to foods were analyzed in a random sample (n=695). Children reporting complete avoidance of milk, egg, cod, or wheat due to perceived hypersensitivity and without physician-diagnosed celiac disease were invited to undergo clinical examination that included specific IgE testing, a celiac screening test, and categorization into phenotypes of food hypersensitivity according to preset criteria. Children with possible food allergy were further evaluated with double-blind challenges. Results In this cohort, the prevalence of reported food allergy to milk, egg, cod, or wheat was 4.8%. Food allergy was diagnosed in 1.4% of the children after clinical evaluation and in 0.6% following double-blind placebo-controlled food challenge. After clinical examination, children who completely avoided one or more essential foods due to perceived food hypersensitivity were categorized with the following phenotypes: allergy (29%), outgrown allergy (19%), lactose intolerance (40%), and unclear (12%). Conclusions There was a high discrepancy in the prevalence of allergy to milk, egg, cod and wheat as assessed by reported data, clinical evaluation, and double-blind food challenges. Food hypersensitivity phenotyping according to preset criteria was helpful for identifying children with food allergy. PMID:26134827

  10. Photoperiod and vernalisation response of Mediterranean wheats, and implications for adaptation

    Microsoft Academic Search

    G. Ortiz Ferrara; M. G. Mosaad; V. Mahalakshmi; S. Rajaram

    1998-01-01

    Hexaploid wheat has the largest cultivated area among crop plants due to its adaptability to different agroclimatic regions.\\u000a A large part of this adaptability depends upon the variation in vernalisation and photoperiod requirements. A better understanding\\u000a of the genetic control of flowering in wheat, as expressed by vernalisation requirements and photoperiod response, will guide\\u000a breeders in targeting crosses of different

  11. Chromosomal rearrangements in the rye genome relative to that of wheat

    Microsoft Academic Search

    Katrien M. Devos; M. D. Atkinson; C. N. Chinoy; H. A. Francis; R. L. Harcourt; R. M. D. Koebner; C. J. Liu; P. Masoj?; D. X. Xie; M. D. Gale

    1993-01-01

    An RFLP-based genetic map of Secale Cereale has provided evidence for multiple evolutionary translocations in the rye genome relative to that of hexaploid wheat. DNA clones which have previously been mapped in wheat indicated that chromosome arms 2RS, 3RL, 4RL, 5RL, 6RS, 6RL, 7RS and 7RL have all been involved in at least one translocation. A possible evolutionary pathway, which

  12. Effect of Microbial Inoculants on the Indigenous Actinobacterial Endophyte Population in the Roots of Wheat as Determined by Terminal Restriction Fragment Length Polymorphism

    PubMed Central

    Conn, Vanessa M.; Franco, Christopher M. M.

    2004-01-01

    The effect of single actinobacterial endophyte seed inoculants and a mixed microbial soil inoculant on the indigenous endophytic actinobacterial population in wheat roots was investigated by using the molecular technique terminal restriction fragment length polymorphism (T-RFLP). Wheat was cultivated either from seeds coated with the spores of single pure actinobacterial endophytes of Microbispora sp. strain EN2, Streptomyces sp. strain EN27, and Nocardioides albus EN46 or from untreated seeds sown in soil with and without a commercial mixed microbial soil inoculant. The endophytic actinobacterial population within the roots of 6-week-old wheat plants was assessed by T-RFLP. Colonization of the wheat roots by the inoculated actinobacterial endophytes was detected by T-RFLP, as were 28 to 42 indigenous actinobacterial genera present in the inoculated and uninoculated plants. The presence of the commercial mixed inoculant in the soil reduced the endophytic actinobacterial diversity from 40 genera to 21 genera and reduced the detectable root colonization by approximately half. The results indicate that the addition of a nonadapted microbial inoculum to the soil disrupted the natural actinobacterial endophyte population, reducing diversity and colonization levels. This was in contrast to the addition of a single actinobacterial endophyte to the wheat plant, where the increase in colonization level could be confirmed even though the indigenous endophyte population was not adversely affected. PMID:15528499

  13. The major threshability genes soft glume ( sog ) and tenacious glume ( Tg ), of diploid and polyploid wheat, trace their origin to independent mutations at non-orthologous loci

    Microsoft Academic Search

    Shilpa Sood; Vasu Kuraparthy; Guihua Bai; Bikram S. Gill

    2009-01-01

    Threshability is an important crop domestication trait. The wild wheat progenitors have tough glumes enveloping the floret\\u000a that make spikes difficult to thresh, whereas cultivated wheats have soft glumes and are free-threshing. In hexaploid wheat,\\u000a the glume tenacity gene Tg along with the major domestication locus Q control threshability. The Q gene was isolated recently and found to be a

  14. MARKER ASSISTED SELECTION FOR FUSARIUM RESISTANCE IN WHEAT FROM DOUBLE HAPLOID POPULATIONS

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Fusarium head blight (FHB) is caused by Fusarium graminearum Schwabe. The fungus can degenerate the wheat grain tissue and produce deoxynivalenol (DON) which is toxic to both human and animals. Epidemics of FHB can result in severe loss of yield and grain quality. Cultural or/and chemical control of...

  15. Effects of tillage on microbial populations associated to soil aggregates under dryland spring wheat system

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Tillage may influence the proportions of microorganisms involved in soil aggregation. We evaluated the effects of no till (NT) and conventional tillage (CT, tillage depth about 7 cm) continuous spring wheat system on bacterial communities predominant in microaggregates (0.25-0.05 mm) and on saprophy...

  16. EVOLUTION OF WHEAT STREAK MOSAIC VIRUS: Dynamics of Population Growth Within Plants May Explain Limited Variation

    Microsoft Academic Search

    Roy C. French; Drake C. Stenger

    2003-01-01

    Like many other plant RNA viruses, Wheat streak mosaic virus (WSMV) sequence diversity within and among infected plants is low given the large number of virions produced. This may be explained by considering aspects of plant virus life history. Intracellular replication of RNA viruses is predominately linear, not exponential, which means that the rate at which mutations accumulate also is

  17. Abundance, variability and chromosomal location of microsatellites in wheat

    Microsoft Academic Search

    Marion S. Röder; Jens Plaschke; Susanne U. König; Andreas Börner; Mark E. Sorrells; Steven D. Tanksley; Martin W. Ganal

    1995-01-01

    The potential of microsatellite sequences as genetic markers in hexaploid wheat (Triticum aestivum) was investigated with respect to their abundance, variability, chromosomal location and usefulness in related species. By screening a lambda phage library, the total number of (GA)n blocks was estimated to be 3.6 x 104 and the number of (GT)n blocks to be 2.3 x 104 per haploid

  18. Quantitative trait loci for resistance against powdery mildew in a segregating wheat×spelt population

    Microsoft Academic Search

    M. Keller; B. Keller; G. Schachermayr; M. Winzeler; J. E. Schmid; P. Stamp; M. M. Messmer

    1999-01-01

    Powdery mildew is one of the major diseases of wheat in regions with a maritime or semi-continental climate and can strongly\\u000a affect grain yield. The attempt to control powdery mildew with major resistance genes (Pm genes) has not provided a durable resistance. Breeding for quantitative resistance to powdery mildew is more promising, but\\u000a is difficult to select on a phenotypic

  19. Moving Waves of Bacterial Populations and Total Organic Carbon along Roots of Wheat

    Microsoft Academic Search

    A. M. Semenov; A. H. C. van Bruggen; V. V. Zelenev

    1999-01-01

    To determine if spatial variation in soluble carbon sources along the root coincides with different trophic groups of bacteria,\\u000a copiotrophic and oligotrophic bacteria were enumerated from bulk soil and rhizosphere samples at 2 cm intervals along wheat\\u000a roots 2, 3, and 4 weeks after planting. There was a moderate rhizosphere effect in one experiment with soil rich in fresh\\u000a plant

  20. The wheat ribosomal DNA spacer region: Its structure and variation in populations and among species

    Microsoft Academic Search

    R. Appels; J. Dvo?ák

    1982-01-01

    The wheat rDNA clone pTA250 was examined in detail to provide a restriction enzyme map and the nucleotide sequence of two of the eleven, 130 bp repeating units found within the spacer region. The 130 bp units showed some sequence heterogeneity. The sequence difference between the two 130 bp units analysed (130.6 and 130.8) was at 7 positions and could

  1. Structure and Temporal Dynamics of Populations within Wheat Streak Mosaic Virus Isolates

    Microsoft Academic Search

    JEFFREY S. HALL; ROY FRENCH; T. JACK MORRIS; DRAKE C. STENGER

    2001-01-01

    Variation within the Type and Sidney 81 strains of wheat streak mosaic virus was assessed by single-strand conformation polymorphism (SSCP) analysis and confirmed by nucleotide sequencing. Limiting-dilution subisolates (LDSIs) of each strain were evaluated for polymorphism in the P1, P3, NIa, and CP cistrons. Different SSCP patterns among LDSIs of a strain were associated with single-nucleotide substitutions. Sidney 81 LDSI-S10

  2. Identification and genetic characterization of an Aegilops tauschii ortholog of the wheat leaf rust disease resistance gene Lr1

    Microsoft Academic Search

    Hong-Qing Ling; Jiwen Qiu; Ravi P. Singh; Beat Keller

    2004-01-01

    Aegilops tauschii (goat grass) is the progenitor of the D genome in hexaploid bread wheat. We have screened more than 200 Ae. tauschii accessions for resistance against leaf rust ( Puccinia triticina) isolates, which are avirulent on the leaf rust resistance gene Lr1. Approximately 3.5% of the Ae. tauschii accessions displayed the same low infection type as the tester line Thatcher

  3. CHROMOSOMAL LOCATIONS OF GENES FOR STEM RUST RESISTANCE IN MONOGENIC LINES DERIVED FROM TETRAPLOID WHEAT ACCESSION ST464

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The genetics of resistance to stem rust (Puccinia graminis Pers.:Pers. f. sp. tritici Eriks. & Henn.) in durum (Triticum turgidum L. ssp. durum) is not as well understood as for hexaploid wheat (T. aestivum L.). Our objective was to determine the chromosomal location of genes for stem rust resistan...

  4. Variation between Ethiopian and North American Barley Varieties (Hordeum vulgare) in Response to Russian Wheat Aphid (Diuraphis noxia) populations

    PubMed Central

    Araya, Alemu; Belay, Tesfay; Hussein, Temam

    2014-01-01

    The Russian wheat aphid, Diuraphis noxia (Mordvilko) (Hemiptera: Aphididae), causes severe damage to barley, Hordeum vulgare L. (Poales: Poaceae), in the highlands of Ethiopia. Little information is available on the control of this pest in Ethiopia. An experiment aimed at evaluating the resistance of barley varieties from the USA to D. noxia populations and determining biotypic variation between Ethiopian and North American D. noxia populations was conducted. The D. noxia-resistant barley varieties Burton and RWA-1758 from the USA, the resistant barley line 3296-15 from Ethiopia, and a local Ethiopian susceptible variety were included in a randomized design in a greenhouse under natural light conditions. There were highly significant differences (P < 0.001) in the mean D. noxia population, leaf chlorosis, leaf rolling, plant stunting, number of tillers per plant, and the percentage of infested tillers per plant between the resistant and susceptible varieties. The aphid population per tiller was lower on the resistant barley plants than on the susceptible plants. Severe plant damage was observed on the local barley variety, while the least damage was observed on Burton, followed by RWA-1758. Burton and RWA-1758 were therefore highly resistant and moderately resistant, respectively, to the northern Ethiopian D. noxia populations, indicating similarities in biotypes between the United States and northern Ethiopian D. noxia populations. The damage to variety 3296-15 was greater than to Burton and RWA-1758. Leaf chlorosis scores and leaf rolling scores for variety 3296-15 upon treatment with the north Ethiopian D. noxia population indicate likely biotypic variation between D. noxia populations of northern and central Ethiopia. PMID:25373187

  5. Association of Size Exclusion HPLC of Endosperm Proteins with Dough Mixing and Bread-making Characteristics in a Recombinant Inbred Population of Hard Red Spring Wheat

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Variation of polymeric proteins is known to affect wheat end-use quality. This research aimed to investigate the composition of polymeric proteins and their associations with dough mixing strength and bread-making characteristics in a near-homogenous population of 139 recombinant inbred lines (RILs...

  6. Genetic Analysis of Bread Making Quality Stability in Wheat using a Halberd X Len Recombinant Inbred Line Population 

    E-print Network

    Poudel, Ashima

    2012-07-16

    Wheat grain quality has a complex genetic architecture heavily influenced by the growing environment. Consistency in wheat quality not only affects the efficiency of milling and baking but also the quality of end-use products. The objectives...

  7. [Sequence polymorphism and mapping of wheat Ca2+-binding protein TaCRT-A gene].

    PubMed

    Wang, Ji-Ping; Mao, Xin-Guo; Li, Run-Zhi; Jing, Rui-Lian

    2012-09-01

    Taking thirty-seven hexaploid wheat (AABBDD) accessions with different drought resistance at seedling stage, three wheat species with A genome (AA), and three tetraploid wheat species (AABB) as test materials, and by direct sequencing the single nucleotide polymorphism (SNP) in TaCRT-A, this paper analyzed the relationships of the SNP with the drought resistance of wheat ( Triticum aestivum) at its seedling stage, and mapped the TaCRT-A on the chromosome of wheat. The full-length sequence of the TaCRT-A genomic DNA was 3887 bp. A total of 202 nucleotide variant loci were observed in the full length sequence of 167141 bp, among which, 165 SNP and 37 InDel with the frequencies of 1 SNP/1013 bp and 1 InDel/4517 bp were detected, respectively. The nucleotide diversity (pi) in coding region of TaCRT-A was lower than that in non-coding region, suggesting that the selection pressure in coding region was stronger than that in non-coding region. The 43 accessions could be classified as 14 haplotypes (H1-H14) by haploid analysis, among which, H1, H2, and H13 all contained one accession which was the donor species of A genome in common wheat, H16 and H7 had one high drought-resistant accession, H8 comprised tetraploid wheat, drought-resistant accessions, and drought-sensitive accessions, whereas H11 included the wheat accessions with drought-resistance and medium-drought resistance. Though the expression of TaCRT was induced by water stress, no significant relationship was identified between TaCRT-A polymorphism and drought resistance. Using a population of recombinant inbred lines derived from a cross of Opata 85 x W7984, the TaCRT-A was mapped between SSR markers Xmwg30 and Xmwg570 on chromosome 3A, and the genetic distances were 10.5 cM and 49.6 cM from the flanking markers, respectively. PMID:23286013

  8. Genetic characterization of North American populations of the wheat curl mite (Aceria tosichella) and dry bulb mite (Aceria tulipae)

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The wheat curl mite, Aceria tosichella Keifer, transmits at least three harmful viruses, wheat streak mosaic virus (WSMV), high plains virus (HPV), and Triticum mosaic virus (TriMV) to wheat (Triticum aestivum L.) throughout the Great Plains. This virus complex is considered to be the most serious d...

  9. Co-ordinate regulation of cytokinin gene family members during flag leaf and reproductive development in wheat

    PubMed Central

    2012-01-01

    Background As the global population continues to expand, increasing yield in bread wheat is of critical importance as 20% of the world’s food supply is sourced from this cereal. Several recent studies of the molecular basis of grain yield indicate that the cytokinins are a key factor in determining grain yield. In this study, cytokinin gene family members in bread wheat were isolated from four multigene families which regulate cytokinin synthesis and metabolism, the isopentenyl transferases (IPT), cytokinin oxidases (CKX), zeatin O-glucosyltransferases (ZOG), and ?-glucosidases (GLU). As bread wheat is hexaploid, each gene family is also likely to be represented on the A, B and D genomes. By using a novel strategy of qRT-PCR with locus-specific primers shared among the three homoeologues of each family member, detailed expression profiles are provided of family members of these multigene families expressed during leaf, spike and seed development. Results The expression patterns of individual members of the IPT, CKX, ZOG, and GLU multigene families in wheat are shown to be tissue- and developmentally-specific. For instance, TaIPT2 and TaCKX1 were the most highly expressed family members during early seed development, with relative expression levels of up to 90- and 900-fold higher, respectively, than those in the lowest expressed samples. The expression of two cis-ZOG genes was sharply increased in older leaves, while an extremely high mRNA level of TaGLU1-1 was detected in young leaves. Conclusions Key genes with tissue- and developmentally-specific expression have been identified which would be prime targets for genetic manipulation towards yield improvement in bread wheat breeding programmes, utilising TILLING and MAS strategies. PMID:22672647

  10. Population Dynamics of Meloidogyne incognita, M. arenaria,and Other Nematodes and Crop Yields in Rotations of Cotton, Peanut, and Wheat Under Minimum Tillage

    PubMed Central

    Johnson, A. W.; Dowler, C. C.; Handoo, Z. A.

    2000-01-01

    Wheat, cotton, and peanut were arranged in three cropping sequences to determine the effects of fenamiphos (6.7 kg a.i./ha) and cropping sequence on nematode population densities and crop yields under conservation tillage and irrigation for 6 years. The cropping sequences included a wheat winter cover crop each year and summer crops of cotton every year, peanut every year, or cotton rotated every other year with peanut. The population densities of Meloidogyne spp. and Helicotylenchus dihystera were determined monthly during the experiment. Numbers of M. incognita increased on cotton and decreased on peanut, whereas M. arenaria increased on peanut, and decreased on cotton; both nematode species remained in moderate to high numbers in plots of wheat. Root damage was more severe on cotton than peanut and was not affected by fenamiphos treatment. The H. dihystera population densities were highest in plots with cotton every summer, intermediate in the cotton-peanut rotation, and lowest in plots with peanut every summer. Over all years and cropping sequences, yield increases in fenamiphos treatment over untreated control were 9% for wheat, 8% for cotton, and 0% for peanut. Peanut yields following cotton were generally higher than yields following peanut. These results show that nematode problems may be manageable in cotton and peanut production under conservation tillage and irrigation in the southeastern United States. PMID:19270949

  11. Constructing an alternative wheat karyotype using barley genomic DNA.

    PubMed

    Icsó, Diána; Molnár-Láng, Márta; Linc, Gabriella

    2015-02-01

    The established karyotype was generated by genomic in situ hybridization (GISH) using total barley genomic DNA as labelled probe on mitotic metaphase bread wheat chromosomes. GISH produced specific banding signals on 16 of the 21 chromosome pairs. The following chromosomes showed distinctive banding patterns: 2A, 3A, 4A, 5A, 6A, 7A, 1D, 2D, 7D and all of the B chromosomes. The remaining chromosomes showed either faint bands or no hybridization signals at all. The in situ hybridization patterns corresponded to the GAA-satellite sequence, which is similar to the N-banding pattern in wheat. In situ hybridization by labelling total barley genomic DNA made it possible to identify most of the bread wheat chromosomes. The present paper describes a GISH-banding method for hexaploid wheat chromosomes. It is a valuable alternative method for fast chromosome selection without using FISH repetitive DNA clones. PMID:25027628

  12. GENES ENCODING PLASTID ACETYL-COA CARBOXYLASE AND 3-PHOSPHOGLYCERATE KINASE OF THE TRITICUM/AEGILOPS COMPLEX AND THE EVOLUTIONARY HISTORY OF POLYPLOID WHEAT.

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The classic wheat evolutionary history is one of adaptive radiation of the diploid Triticum/Aegilops species (A, S, D) , genome convergence and divergence of the tetraploid (T. turgidum AABB, and T. timopheevii AAAGG) and hexaploid (T. aestivum, AABBDD) species. The objective of this study was to a...

  13. Differential expression of the pathogenesis-related protein 1 (PR-1) gene family in stem rust (Puccinia graminis f. sp. tritici )-wheat interactions

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The group 1 pathogenesis-related (PR-1) proteins, known as hallmarks of defense pathways, are encoded by a multigene family in hexaploid wheat (Triticum aestivum L.) that includes at least 12 closely related TaPr-1 genes responsive to infection by the necrotrophic pathogen Stagonospora nodorum (Sn) ...

  14. Variation in virulence to wheat in Pyrenophora tritici-repentis population from Saskatchewan, Canada, from 2000 to 2002

    Microsoft Academic Search

    P. K. Singh; M. Mergoum; G. R. Hughes

    2007-01-01

    Tan spot, caused by Pyrenophora tritici-repentis, is an economically important disease of wheat worldwide. Isolates of P. tritici-repentis are presently classified into eight races on the basis of their virulence (ability to induce necrosis and (or) chlorosis) on a set of wheat differential cultivars. A total of 337 isolates of P. tritici-repentis from leaves of common wheat (Triticum aestivum), durum

  15. Consumption of pesticide-treated wheat seed by a rural population in Malawi.

    PubMed

    Schier, Joshua G; Sejvar, James J; Lutterloh, Emily; Likaka, Andrew; Katsoudas, Eugenia; Karaseva, Yelena D; Tippett Barr, Beth; Redwood, Yanique; Monroe, Stephan

    2012-11-01

    An outbreak of typhoid fever in rural Malawi triggered an investigation by the Malawi Ministry of Health and the Centers for Disease Control and Prevention in July 2009. During the investigation, villagers were directly consuming washed, donated, pesticide-treated wheat seed meant for planting. The objective of this study was to evaluate the potential for pesticide exposure and health risk in the outbreak community. A sample of unwashed (1430?g) and washed (759?g) wheat seed donated for planting, but which would have been directly consumed, was tested for 365 pesticides. Results were compared with each other (percentage change), the US Environmental Protection Agency's (EPA) health guidance values and estimated daily exposures were compared with their Reference dose (RfD). Unwashed and washed seed samples contained, respectively: carboxin, 244 and 57?p.p.m.; pirimiphos methyl, 8.18 and 8.56?p.p.m.; total permethrin, 3.62 and 3.27?p.p.m.; and carbaryl, 0.057 and 0.025?p.p.m.. Percentage change calculations (unwashed to washed) were as follows: carboxin, -76.6%; pirimiphos methyl, +4.6%; total permethrin, -9.7%; and carbaryl -56.1%. Only carboxin and total permethrin concentration among washed seed samples exceeded US EPA health guidance values (285 × and seven times, respectively). Adult estimated exposure scenarios (1?kg seed) exceeded the RfD for carboxin (8 × ) and pirimiphos methyl (12 × ). Adult villagers weighing 70?kg would have to consume 0.123, 0.082, 1.06, and 280?kg of washed seed daily to exceed the RfD for carboxin, pirimiphos methyl, permethrins, and carbaryl, respectively. Carboxin, pirimiphos methyl, permethrins, and carbaryl were detected in both unwashed and washed samples of seed. Carboxin, total permethrin, and carbaryl concentration were partially reduced by washing. Health risks from chronic exposure to carboxin and pirimiphos methyl in these amounts are unclear. The extent of this practice among food insecure communities receiving relief seeds and resultant health impact needs further study. PMID:23047320

  16. EVIDENCE FOR FREQUENT RECOMBINATION IN A WHEAT STREAK MOSAIC VIRUS POPULATION

    Technology Transfer Automated Retrieval System (TEKTRAN)

    There are two types of recombination events of interest in RNA viruses. One is between divergent virus populations or virus species. The other is between members of the same population. The former is perhaps important for long-term virus evolution while the latter could serve as a mechanism to preve...

  17. Reconstruction of the synthetic W9784 x Opata85 wheat reference population

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Reference populations are a valuable resource in genetics studies of crop species for determining marker order, marker selection, trait mapping, construction of large-insert libraries, cross-referencing marker platforms, and genome sequencing. Useful reference populations can be propagated indefinit...

  18. Biosystematic study of hexaploids Elymus tschimganicus and E. glaucissimus. I. Morphology and genomic constitution

    Microsoft Academic Search

    Kevin B. Jensen; Zhi-Wu Liu; Bao-Rong Lu; Bjoin Solamon

    1994-01-01

    Elymus tschimganicus andE. glaucissimus are hexaploids (2n = 6x = 42) that inhabit stony slopes and swales in the middle and upper mountain belts of Central Asia. Chromosome pairing at metaphase I inE. tschimganicus andE. glaucissimus was typical of otherElymus hexaploids, averaging 20.94 and 20.98 bivalents per cell, respectively. Meiotic pairing of tetraploid hybrids derived by crossingE. tschimganicus andE. glaucissimus

  19. O-Glucosyltransferase activities toward phenolic natural products and xenobiotics in wheat and herbicide-resistant and herbicide-susceptible black-grass (Alopecurus myosuroides).

    PubMed

    Brazier, Melissa; Cole, David J; Edwards, Robert

    2002-01-01

    Herbicide safeners manipulate herbicide selectivity by enhancing the activities of detoxifying enzymes, such as glutathione transferases (GSTs) and cytochrome P450 mono-oxygenases (CYPs) in cereal crops. As part of a study examining the importance of O-glucosyltransferases (OGTs) in pesticide metabolism in hexaploid bread wheat (Triticum aestivum L.), seedlings were grown in the presence of dichlormid, a safener used in maize and cloquintocet mexyl, a wheat safener. The efficacy of the treatments was confirmed by monitoring changes in the abundance of phi and tau class GSTs. OGT activities in the root and shoot tissue were assayed using phenolics of natural and xenobiotic origin to determine if they were enhanced by safeners. Cloquintocet mexyl selectively increased OGT activities toward xenobiotics (4-nitrophenol and 2,4,5-trichlorophenol) and flavonoids, (quercetin, luteolin, genistein and coumestrol) in both the roots and shoots. However, OGT activity towards simple phenols and phenylpropanoids was not enhanced by cloquintocet mexyl. Dichlormid was a much weaker enhancer of OGT activity, with the same subset of OGT activities increased as determined with cloquintocet mexyl, but with the effect being largely restricted to the roots. OGT activities were also determined in black-grass (Alopecurus myosuroides L.), an agronomically important weed in wheat. Two populations of black-grass differing in their sensitivity to herbicides were analysed. The population Peldon, which is resistant to multiple classes of herbicides due in part to the elevated expression of CYPs and GSTs active in herbicide detoxification, contained higher OGT activities than herbicide sensitive black-grass. Unlike wheat, treatment with cloquintocet mexyl or dichlormid, had no effect on OGT activities in either black-grass population. PMID:11809449

  20. Applicability of inter-simple sequence repeat polymorphisms in wheat for use as DNA markers in comparison to RFLP and RAPD markers

    Microsoft Academic Search

    T. Nagaoka; Y. Ogihara

    1997-01-01

    Inter-simple sequence repeat polymorphic DNA (ISSR) was evaluated for its applicability as a genetic marker system in wheat.\\u000a PCR was carried out with primers that annealed to simple sequence repeats. The resultant products were subjected to agarose-gel\\u000a electrophoresis, and the banding patterns were compared among six wheat accessions containing diploid, tetraploid, and hexaploid\\u000a members. Out of 100 examined, 33 primers

  1. High resolution melting analysis for the detection of EMS induced mutations in wheat SbeIIa genes

    PubMed Central

    2011-01-01

    Background Manipulation of the amylose-amylopectin ratio in cereal starch has been identified as a major target for the production of starches with novel functional properties. In wheat, silencing of starch branching enzyme genes by a transgenic approach reportedly caused an increase of amylose content up to 70% of total starch, exhibiting novel and interesting nutritional characteristics. In this work, the functionality of starch branching enzyme IIa (SBEIIa) has been targeted in bread wheat by TILLING. An EMS-mutagenised wheat population has been screened using High Resolution Melting of PCR products to identify functional SNPs in the three homoeologous genes encoding the target enzyme in the hexaploid genome. Results This analysis resulted in the identification of 56, 14 and 53 new allelic variants respectively for SBEIIa-A, SBEIIa-B and SBEIIa-D. The effects of the mutations on protein structure and functionality were evaluated by a bioinformatic approach. Two putative null alleles containing non-sense or splice site mutations were identified for each of the three homoeologous SBEIIa genes; qRT-PCR analysis showed a significant decrease of their gene expression and resulted in increased amylose content. Pyramiding of different single null homoeologous allowed to isolate double null mutants showing an increase of amylose content up to 21% compared to the control. Conclusion TILLING has successfully been used to generate novel alleles for SBEIIa genes known to control amylose content in wheat. Single and double null SBEIIa genotypes have been found to show a significant increase in amylose content. PMID:22074448

  2. SNP and haplotype identification of the wheat monomeric alpha-amylase inhibitor genes.

    PubMed

    Wang, Ji-Rui; Wei, Yu-Ming; Yan, Ze-Hong; Zheng, You-Liang

    2008-11-01

    Seventy-three gene sequences encoding monomeric alpha-amylase inhibitors were characterized from cultivated wheat "Chinese Spring", group 6 nullisomic-tetrasomic lines of "Chinese Spring" and diploid putative progenitors of common wheat. The monomeric alpha-amylase inhibitors from the different sources shared very high homology (99.54%). The different alpha-amylase inhibitors, which were determined by the 24 single nucleotide polymorphisms (SNPs) of their gene sequences, were investigated. A total of 15 haplotypes were defined by sequence alignment, among which 9 haplotypes were found with only one single sequence sample. Haplotype H02 was found to be the main haplotype occurring in 83 WMAI sequence samples, followed by haplotype H11. The median-joining network for the 15 haplotypes of monomeric alpha-amylase inhibitor gene sequences from hexaploid wheats was star like, and at least two subclusters emerged. Furthermore evidence of homologous recombination was found between the haplotypes. The relationship between nucleotide substitutions and the amino acid changes in WMAI of hexaploid wheats was summarized. It was clear that only five polymorphic sites in the nucleotide sequence of WMAI resulted in amino acid variations, and that should be the reason for different structure and function of inhibitors. However, little evidence could be found that there were WMAI genes in the A genome of hexaploid wheat, whereas it could conclude from our results that the A genome diploid wheat had WMAI genes. The overall information on the monomeric alpha-amylase inhibitors from wheat and Aegilops strongly support the view that these inhibitors have evolved from a common ancestral gene through duplication and mutation. PMID:18060568

  3. Population-Specific Patterns of Linkage Disequilibrium and SNP Variation in Spring and Winter Polyploid Wheat

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Single nucleotide polymorphisms (SNPs) are ideally suited for the construction of high-resolution genetic maps, studying population evolutionary history and performing genome-wide association mapping experiments. Here we used a genome-wide set of 1536 SNPs to study linkage disequilibrium (LD) and po...

  4. Identification of inter simple sequence repeat (ISSR) markers associated with seed size in wheat

    Microsoft Academic Search

    J. S. S. Ammiraju; B. B. Dholakia; D. K. Santra; H. Singh; M. D. Lagu; S. A. Tamhankar; H. S. Dhaliwal; V. S. Rao; V. S. Gupta; P. K. Ranjekar

    2001-01-01

    The feasibility of identifying inter-simple sequence repeat markers associated with seed weight in hexaploid wheat was tested\\u000a using 113 recombinant inbred lines developed by the single-seed descent method, from a cross between Rye selection111, an\\u000a Indian genetic stock obtained through the introgression of genes for bold seed size from rye, and Chinese Spring having small\\u000a seed size. Three markers were

  5. Population structure within lineages of Wheat streak mosaic virus derived from a common founding event exhibits stochastic variation inconsistent with the deterministic quasi-species model

    SciTech Connect

    French, Roy [Agricultural Research Service, United States Department of Agriculture and Department of Plant Pathology, University of Nebraska, Lincoln, NE 68583 (United States); Stenger, Drake C. [Agricultural Research Service, United States Department of Agriculture and Department of Plant Pathology, University of Nebraska, Lincoln, NE 68583 (United States)]. E-mail: dstenger@unlnotes.unl.edu

    2005-12-20

    Structure of Wheat streak mosaic virus (WSMV) populations derived from a common founding event and subjected to serial passage at high multiplicity of infection (MOI) was evaluated. The founding population was generated by limiting dilution inoculation. Lineages of known pedigree were sampled at passage 9 (two populations) and at passage 15, with (three populations) or without mixing (four populations) of lineages at passage 10. Polymorphism within each population was assessed by sequencing 17-21 clones containing a 1371 nt region (WSMV-Sidney 81 nts 8001-9371) encompassing the entire coat protein cistron and flanking regions. Mutation frequency averaged {approx}5.0 x 10{sup -4}/nt across all populations and ranged from 2.4 to 11.6 x 10{sup -4}/nt within populations, but did not consistently increase or decrease with the number of passages removed from the founding population. Shared substitutions (19 nonsynonymous, 10 synonymous, and 3 noncoding) occurred at 32 sites among 44 haplotypes. Only four substitutions became fixed (frequency = 100%) within a population and nearly one third (10/32) never achieved a frequency of 10% or greater in any sampled population. Shared substitutions were randomly distributed with respect to genome position, with transitions outnumbering transversions 5.4:1 and a clear bias for A to G and U to C substitutions. Haplotype composition of each population was unique with complexity of each population varying unpredictably, in that the number and frequency of haplotypes within a lineage were not correlated with number of passages removed from the founding population or whether the population was derived from a single or mixed lineage. The simplest explanation is that plant virus lineages, even those propagated at high MOI, are subject to frequent, narrow genetic bottlenecks during systemic movement that result in low effective population size and stochastic changes in population structure upon serial passage.

  6. Taxonomic Structure and Monitoring of the Dominant Population of Lactic Acid Bacteria during Wheat Flour Sourdough Type I Propagation Using Lactobacillus sanfranciscensis Starters?

    PubMed Central

    Siragusa, Sonya; Di Cagno, Raffaella; Ercolini, Danilo; Minervini, Fabio; Gobbetti, Marco; De Angelis, Maria

    2009-01-01

    The structure and stability of the dominant lactic acid bacterium population were assessed during wheat flour sourdough type I propagation by using singly nine strains of Lactobacillus sanfranciscensis. Under back-slopping propagation with wheat flour type 0 F114, cell numbers of presumptive lactic acid bacteria varied slightly between and within starters. As determined by randomly amplified polymorphic DNA-PCR and restriction endonuclease analysis-pulsed-field gel electrophoresis analyses, only three (LS8, LS14, and LS44) starters dominated throughout 10 days of propagation. The others progressively decreased to less than 3 log CFU g?1. Partial sequence analysis of the 16S rRNA and recA genes and PCR-denaturating gradient gel electrophoresis analysis using the rpoB gene allowed identification of Weissella confusa, Lactobacillus sanfranciscensis, Lactobacillus plantarum, Lactobacillus rossiae, Lactobacillus brevis, Lactococcus lactis subsp. lactis, Pediococcus pentosaceus, and Lactobacillus spp. as the dominant species of the raw wheat flour. At the end of propagation, one autochthonous strain of L. sanfranciscensis was found in all the sourdoughs. Except for L. brevis, strains of the above species were variously found in the mature sourdoughs. Persistent starters were found in association with other biotypes of L. sanfranciscensis and with W. confusa or L. plantarum. Sourdoughs were characterized for acidification, quotient of fermentation, free amino acids, and community-level catabolic profiles by USING Biolog 96-well Eco microplates. In particular, catabolic profiles of sourdoughs containing persistent starters behaved similarly and were clearly differentiated from the others. The three persistent starters were further used for the production of sourdoughs and propagated by using another wheat flour whose lactic acid bacterium population in part differed from the previous one. Also, in this case all three starter strains persisted during propagation. PMID:19088320

  7. Wheat Improvement Programs WHEAT PROGRAM

    E-print Network

    Wheat Improvement Programs WHEAT PROGRAM The small grains improvement effort at Texas Agri techniques. The College Station center focuses on wheat and oats for the South Texas and Blacklands regions of Texas, while the Amarillo center develops wheat and triticale lines for the Texas High Plains

  8. Wheat Streak Mosaic Virus

    E-print Network

    Morgan, Gaylon

    2005-01-26

    Virus First discovered in Nebraska in 1922, wheat streak mosaic virus (WSMV) remains a threat today across most of the U.S. Central Plains. WSMV affects spring wheat, barley, corn, triticale, rye and numerous other annual and perennial grasses... have tre- mendous reproductive capability, enabling large populations to build. The mite is most active during warm weather, with temperatures of 75-80 degrees F optimum for reproduction. Mites require a living grass host to survive the summer; sum...

  9. Synthesis of trigeneric hybrids of hexaploid wheat with diploid wheatgrasses: Specificity of chromosome pairing

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Wild grasses in the tribe Triticeae are excellent sources of genes for superior traits, including resistance to various diseases. Diploid wheatgrasses – Lophopyrum elongatum (Host) Á. Löve (2n = 2x = 14; EE genome) and Thinopyrum bessarabicum (Savul. & Rayss) Á. Löve (2n = 2x = 14; JJ genome) – are...

  10. Molecular detection of QTLs for agronomic and quality traits in a doubled haploid population derived from two Canadian wheats (Triticum aestivum L.).

    PubMed

    Huang, X Q; Cloutier, S; Lycar, L; Radovanovic, N; Humphreys, D G; Noll, J S; Somers, D J; Brown, P D

    2006-08-01

    Development of high-yielding wheat varieties with good end-use quality has always been a major concern for wheat breeders. To genetically dissect quantitative trait loci (QTLs) for yield-related traits such as grain yield, plant height, maturity, lodging, test weight and thousand-grain weight, and for quality traits such as grain and flour protein content, gluten strength as evaluated by mixograph and SDS sedimentation volume, an F1-derived doubled haploid (DH) population of 185 individuals was developed from a cross between a Canadian wheat variety "AC Karma" and a breeding line 87E03-S2B1. A genetic map was constructed based on 167 marker loci, consisting of 160 microsatellite loci, three HMW glutenin subunit loci: Glu-A1, Glu-B1 and Glu-D1, and four STS-PCR markers. Data for investigated traits were collected from three to four environments in Manitoba, Canada. QTL analyses were performed using composite interval mapping. A total of 50 QTLs were detected, 24 for agronomic traits and 26 for quality-related traits. Many QTLs for correlated traits were mapped in the same genomic regions forming QTL clusters. The largest QTL clusters, consisting of up to nine QTLs, were found on chromosomes 1D and 4D. HMW glutenin subunits at Glu-1 loci had the largest effect on breadmaking quality; however, other genomic regions also contributed genetically to breadmaking quality. QTLs detected in the present study are compared with other QTL analyses in wheat. PMID:16838135

  11. Recent emergence of the wheat Lr34 multi-pathogen resistance: insights from haplotype analysis in wheat, rice, sorghum and Aegilops tauschii.

    PubMed

    Krattinger, Simon G; Jordan, David R; Mace, Emma S; Raghavan, Chitra; Luo, Ming-Cheng; Keller, Beat; Lagudah, Evans S

    2013-03-01

    Spontaneous sequence changes and the selection of beneficial mutations are driving forces of gene diversification and key factors of evolution. In highly dynamic co-evolutionary processes such as plant-pathogen interactions, the plant's ability to rapidly adapt to newly emerging pathogens is paramount. The hexaploid wheat gene Lr34, which encodes an ATP-binding cassette (ABC) transporter, confers durable field resistance against four fungal diseases. Despite its extensive use in breeding and agriculture, no increase in virulence towards Lr34 has been described over the last century. The wheat genepool contains two predominant Lr34 alleles of which only one confers disease resistance. The two alleles, located on chromosome 7DS, differ by only two exon-polymorphisms. Putatively functional homoeologs and orthologs of Lr34 are found on the B-genome of wheat and in rice and sorghum, but not in maize, barley and Brachypodium. In this study we present a detailed haplotype analysis of homoeologous and orthologous Lr34 genes in genetically and geographically diverse selections of wheat, rice and sorghum accessions. We found that the resistant Lr34 haplotype is unique to the wheat D-genome and is not found in the B-genome of wheat or in rice and sorghum. Furthermore, we only found the susceptible Lr34 allele in a set of 252 Ae. tauschii genotypes, the progenitor of the wheat D-genome. These data provide compelling evidence that the Lr34 multi-pathogen resistance is the result of recent gene diversification occurring after the formation of hexaploid wheat about 8,000 years ago. PMID:23117720

  12. Analogy potential effects of planting methods and t ank mixed herbicides on wheat yield and weed populations

    Microsoft Academic Search

    S. Sedigheh

    2009-01-01

    The aim of integrated weed management (IWM) was to use the combination of different practices to maintain weed densities at manageable levels. A field experiment was conducted at Agricultural College, Tehran of University, in K araj city 2005-2006 by planting wheat, to investigate the response of planting methods and ta nk mixed herbicides. The experiment was laid out using a

  13. Population Structure, Linkage Disequilibrium, and Genetic Diversity in Soft Winter Wheat Enriched for Fusarium Head Blight Resistance

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The occurrence of epidemics of Fusarium head blight (FHB), caused by Fusarium graminearum Schwabe, in U.S. winter wheat (Triticum aestivum L.) during the past two decades has resulted in increased emphasis on development of resistant cultivars. Understanding the effect of focused breeding efforts fo...

  14. Population Dynamics and Metabolite Target Analysis of Lactic Acid Bacteria during Laboratory Fermentations of Wheat and Spelt Sourdoughs

    Microsoft Academic Search

    Roel Van der Meulen; Ilse Scheirlinck; Ann Van Schoor; Geert Huys; Marc Vancanneyt; Peter Vandamme; Luc De Vuyst

    2007-01-01

    Four laboratory sourdough fermentations, initiated with wheat or spelt flour and without the addition of a starter culture, were prepared over a period of 10 days with daily back-slopping. Samples taken at all refreshment steps were used for determination of the present microbiota. Furthermore, an extensive metabolite target analysis of more than 100 different compounds was performed through a combination

  15. Use of wild relatives to improve salt tolerance in wheat.

    PubMed

    Colmer, Timothy D; Flowers, Timothy J; Munns, Rana

    2006-01-01

    There is considerable variability in salt tolerance amongst members of the Triticeae, with the tribe even containing a number of halophytes. This is a review of what is known of the differences in salt tolerance of selected species in this tribe of grasses, and the potential to use wild species to improve salt tolerance in wheat. Most investigators have concentrated on differences in ion accumulation in leaves, describing a desirable phenotype with low leaf Na+ concentration and a high K+/Na+ ratio. Little information is available on other traits (such as "tissue tolerance" of accumulated Na+ and Cl-) that might also contribute to salt tolerance. The sources of Na+ "exclusion" amongst the various genomes that make up tetraploid (AABB) durum wheat (Triticum turgidum L. ssp. durum), hexaploid (AABBDD) bread wheat (Triticum aestivum L. ssp. aestivum), and wild relatives (e.g. Aegilops spp., Thinopyrum spp., Elytrigia elongata syn. Lophopyrum elongatum, Hordeum spp.) are described. The halophytes display a capacity for Na+ "exclusion", and in some cases Cl- "exclusion", even at relatively high salinity. Significantly, it is possible to hybridize several wild species in the Triticeae with durum and bread wheat. Progenitors have been used to make synthetic hexaploids. Halophytic relatives, such as tall wheatgrass spp., have been used to produce amphiploids, disomic chromosome addition and substitution lines, and recombinant lines in wheat. Examples of improved Na+ "exclusion" and enhanced salt tolerance in various derivatives from these various hybridization programmes are given. As several sources of improved Na+ "exclusion" are now known to reside on different chromosomes in various genomes of species in the Triticeae, further work to identify the underlying mechanisms and then to pyramid the controlling genes for the various traits, that could act additively or even synergistically, might enable substantial gains in salt tolerance to be achieved. PMID:16513812

  16. Quality (End-Use) Improvement in Wheat

    Microsoft Academic Search

    R. J. Peña; R. Trethowan; W. H. Pfeiffer; M. Van Ginkel

    2002-01-01

    Wheat provides nutrients and the raw materials for industrialized food production. Recent global economic trends and increases in urban population growth have led to an increased demand for wheat-based convenience foods (fast, ready-to-eat, frozen foods, etc.) and for new wheat-based products. These factors have resulted in a greater emphasis than ever on the end-use quality of wheat. This paper reviews

  17. The making of a new pathogen: Insights from comparative population genomics of the domesticated wheat pathogen Mycosphaerella graminicola and its wild sister species

    PubMed Central

    Stukenbrock, Eva H.; Bataillon, Thomas; Dutheil, Julien Y.; Hansen, Troels T.; Li, Ruiqiang; Zala, Marcello; McDonald, Bruce A.; Wang, Jun; Schierup, Mikkel H.

    2011-01-01

    The fungus Mycosphaerella graminicola emerged as a new pathogen of cultivated wheat during its domestication ?11,000 yr ago. We assembled 12 high-quality full genome sequences to investigate the genetic footprints of selection in this wheat pathogen and closely related sister species that infect wild grasses. We demonstrate a strong effect of natural selection in shaping the pathogen genomes with only ?3% of nonsynonymous mutations being effectively neutral. Forty percent of all fixed nonsynonymous substitutions, on the other hand, are driven by positive selection. Adaptive evolution has affected M. graminicola to the highest extent, consistent with recent host specialization. Positive selection has prominently altered genes encoding secreted proteins and putative pathogen effectors supporting the premise that molecular host–pathogen interaction is a strong driver of pathogen evolution. Recent divergence between pathogen sister species is attested by the high degree of incomplete lineage sorting (ILS) in their genomes. We exploit ILS to generate a genetic map of the species without any crossing data, document recent times of species divergence relative to genome divergence, and show that gene-rich regions or regions with low recombination experience stronger effects of natural selection on neutral diversity. Emergence of a new agricultural host selected a highly specialized and fast-evolving pathogen with unique evolutionary patterns compared with its wild relatives. The strong impact of natural selection, we document, is at odds with the small effective population sizes estimated and suggest that population sizes were historically large but likely unstable. PMID:21994252

  18. Evolution of the Oat Genetic Road Map: From Tetraploid to Hexaploid

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The development of a genetic linkage map for hexaploid oat (Avena sativa L. 2n = 6 x = 42) that defines all 21 chromosomes has been hindered due to the lack of oat-based markers and the size and complexity of the oat genome. Recent efforts in oat DArT, SSR, and SNP marker development should improve...

  19. Trigenomic origin of the hexaploid Psammopyrum athericum (Triticeae: Poaceae) revealed by in-situ hybridization

    Microsoft Academic Search

    Pernilla Ellneskog-Staam; Björn Salomon; Roland von Bothmer; Kesara Anamthawat-Jònsson

    2001-01-01

    The genomic constitution of the hexaploid Psammopyrum athericum was studied with in-situ DNA hybridization using both genomic DNA and isolated cloned sequences as probes. A genomic probe from Thinopyrum bessarabicum (E genome) hybridized successfully to 14 chromosomes of Ps. athericum and a probe from Festucopsis serpentinii (L genome) hybridized to another 14 chromosomes. The remaining chromosomes did not hybridize, apart

  20. Genome-Wide Quantitative Trait Locus Mapping Identifies Multiple Major Loci for Brittle Rachis and Threshability in Tibetan Semi-Wild Wheat (Triticum aestivum ssp. tibetanum Shao)

    PubMed Central

    Luo, Wei; Kong, Xing-Chen; Qi, Peng-Fei; Wang, Ji-Rui; Wei, Yu-Ming; Jiang, Qian-Tao; Liu, Ya-Xi; Peng, Yuan-Ying; Chen, Guo-Yue; Dai, Shou-Fen; Zheng, You-Liang

    2014-01-01

    Tibetan semi-wild wheat (Triticum aestivum ssp. tibetanum Shao) is a semi-wild hexaploid wheat resource that is only naturally distributed in the Qinghai-Tibet Plateau. Brittle rachis and hard threshing are two important characters of Tibetan semi-wild wheat. A whole-genome linkage map of T. aestivum ssp. tibetanum was constructed using a recombinant inbred line population (Q1028×ZM9023) with 186 lines, 564 diversity array technology markers, and 117 simple sequence repeat markers. Phenotypic data on brittle rachis and threshability, as two quantitative traits, were evaluated on the basis of the number of average spike rachis fragments per spike and percent threshability in 2012 and 2013, respectively. Quantitative trait locus (QTL) mapping performed using inclusive composite interval mapping analysis clearly identified four QTLs for brittle rachis and three QTLs for threshability. However, three loci on 2DS, 2DL, and 5AL showed pleiotropism for brittle rachis and threshability; they respectively explained 5.3%, 18.6%, and 18.6% of phenotypic variation for brittle rachis and 17.4%, 13.2%, and 35.2% of phenotypic variation for threshability. A locus on 3DS showed an independent effect on brittle rachis, which explained 38.7% of the phenotypic variation. The loci on 2DS and 3DS probably represented the effect of Tg and Br1, respectively. The locus on 5AL was in very close proximity to the Q gene, but was different from the predicted q in Tibetan semi-wild wheat. To our knowledge, the locus on 2DL has never been reported in common wheat but was prominent in T. aestivum ssp. tibetanum accession Q1028. It remarkably interacted with the locus on 5AL to affect brittle rachis. Several major loci for brittle rachis and threshability were identified in Tibetan semi-wild wheat, improving the understanding of these two characters and suggesting the occurrence of special evolution in Tibetan semi-wild wheat. PMID:25474652

  1. On-farm dynamic management of genetic diversity: the impact of seed diffusions and seed saving practices on a population-variety of bread wheat

    PubMed Central

    Thomas, Mathieu; Demeulenaere, Elise; Dawson, Julie C; Khan, Abdul Rehman; Galic, Nathalie; Jouanne-Pin, Sophie; Remoue, Carine; Bonneuil, Christophe; Goldringer, Isabelle

    2012-01-01

    Since the domestication of crop species, humans have derived specific varieties for particular uses and shaped the genetic diversity of these varieties. Here, using an interdisciplinary approach combining ethnobotany and population genetics, we document the within-variety genetic structure of a population-variety of bread wheat (Triticum aestivum L.) in relation to farmers’ practices to decipher their contribution to crop species evolution. Using 19 microsatellites markers, we conducted two complementary graph theory-based methods to analyze population structure and gene flow among 19 sub-populations of a single population-variety [Rouge de Bordeaux (RDB)]. The ethnobotany approach allowed us to determine the RDB history including diffusion and reproduction events. We found that the complex genetic structure among the RDB sub-populations is highly consistent with the structure of the seed diffusion and reproduction network drawn based on the ethnobotanical study. This structure highlighted the key role of the farmer-led seed diffusion through founder effects, selection and genetic drift because of human practices. An important result is that the genetic diversity conserved on farm is complementary to that found in the genebank indicating that both systems are required for a more efficient crop diversity conservation. PMID:23346224

  2. Estimation of genetic parameters of a DH wheat population grown at different N stress levels characterized by probe genotypes

    Microsoft Academic Search

    Anne Laperche; Maryse Brancourt-Hulmel; Emmanuel Heumez; Olivier Gardet; Jacques Le Gouis

    2006-01-01

    Low market prices and environmental concerns in Europe favor lower input wheat production systems. To efficiently breed for\\u000a new varieties adapted to low input management while maintaining high yield levels, our objective was to characterize the heritability\\u000a and its components for yield and nitrogen traits under different nitrogen levels. Two hundred and twenty-two doubled-haploid\\u000a (DH) lines from the cross between

  3. Sequence polymorphism in polyploid wheat and their d-genome diploid ancestor.

    PubMed Central

    Caldwell, Katherine S; Dvorak, Jan; Lagudah, Evans S; Akhunov, Eduard; Luo, Ming-Cheng; Wolters, Petra; Powell, Wayne

    2004-01-01

    Sequencing was used to investigate the origin of the D genome of the allopolyploid species Triticum aestivum and Aegilops cylindrica. A 247-bp region of the wheat D-genome Xwye838 locus, encoding ADP-glucopyrophosphorylase, and a 326-bp region of the wheat D-genome Gss locus, encoding granule-bound starch synthase, were sequenced in a total 564 lines of hexaploid wheat (T. aestivum, genome AABBDD) involving all its subspecies and 203 lines of Aegilops tauschii, the diploid source of the wheat D genome. In Ae. tauschii, two SNP variants were detected at the Xwye838 locus and 11 haplotypes at the Gss locus. Two haplotypes with contrasting frequencies were found at each locus in wheat. Both wheat Xwye838 variants, but only one of the Gss haplotypes seen in wheat, were found among the Ae. tauschii lines. The other wheat Gss haplotype was not found in either Ae. tauschii or 70 lines of tetraploid Ae. cylindrica (genomes CCDD), which is known to hybridize with wheat. It is concluded that both T. aestivum and Ae. cylindrica originated recurrently, with at least two genetically distinct progenitors contributing to the formation of the D genome in both species. PMID:15238542

  4. Sequence polymorphism in polyploid wheat and their d-genome diploid ancestor.

    PubMed

    Caldwell, Katherine S; Dvorak, Jan; Lagudah, Evans S; Akhunov, Eduard; Luo, Ming-Cheng; Wolters, Petra; Powell, Wayne

    2004-06-01

    Sequencing was used to investigate the origin of the D genome of the allopolyploid species Triticum aestivum and Aegilops cylindrica. A 247-bp region of the wheat D-genome Xwye838 locus, encoding ADP-glucopyrophosphorylase, and a 326-bp region of the wheat D-genome Gss locus, encoding granule-bound starch synthase, were sequenced in a total 564 lines of hexaploid wheat (T. aestivum, genome AABBDD) involving all its subspecies and 203 lines of Aegilops tauschii, the diploid source of the wheat D genome. In Ae. tauschii, two SNP variants were detected at the Xwye838 locus and 11 haplotypes at the Gss locus. Two haplotypes with contrasting frequencies were found at each locus in wheat. Both wheat Xwye838 variants, but only one of the Gss haplotypes seen in wheat, were found among the Ae. tauschii lines. The other wheat Gss haplotype was not found in either Ae. tauschii or 70 lines of tetraploid Ae. cylindrica (genomes CCDD), which is known to hybridize with wheat. It is concluded that both T. aestivum and Ae. cylindrica originated recurrently, with at least two genetically distinct progenitors contributing to the formation of the D genome in both species. PMID:15238542

  5. Resistance among U.S. wheat Triticum aestivum cultivars to the wheat pathotype of Magnaporthe oryzae

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Magnaporthe oryzae is the causal agent of blast on several graminaceous plants. The M. oryzae population causing wheat blast has not been found outside South America. U.S. wheat production is at risk to this pathogen if introduced and established. Proactive testing of US wheat cultivars for their re...

  6. Relationship between Russian wheat aphid abundance and edaphic and topographic characteristics of wheat fields

    Technology Transfer Automated Retrieval System (TEKTRAN)

    This study explores the spatial relationship between Russian wheat aphid population density and variation in edaphic or topographic factors within wheat fields. Multiple regression analysis was applied to data collected from six wheat fields located in three States, Colorado, Wyoming, and Nebraska....

  7. Structural and functional partitioning of bread wheat chromosome 3B.

    PubMed

    Choulet, Frédéric; Alberti, Adriana; Theil, Sébastien; Glover, Natasha; Barbe, Valérie; Daron, Josquin; Pingault, Lise; Sourdille, Pierre; Couloux, Arnaud; Paux, Etienne; Leroy, Philippe; Mangenot, Sophie; Guilhot, Nicolas; Le Gouis, Jacques; Balfourier, Francois; Alaux, Michael; Jamilloux, Véronique; Poulain, Julie; Durand, Céline; Bellec, Arnaud; Gaspin, Christine; Safar, Jan; Dolezel, Jaroslav; Rogers, Jane; Vandepoele, Klaas; Aury, Jean-Marc; Mayer, Klaus; Berges, Hélène; Quesneville, Hadi; Wincker, Patrick; Feuillet, Catherine

    2014-07-18

    We produced a reference sequence of the 1-gigabase chromosome 3B of hexaploid bread wheat. By sequencing 8452 bacterial artificial chromosomes in pools, we assembled a sequence of 774 megabases carrying 5326 protein-coding genes, 1938 pseudogenes, and 85% of transposable elements. The distribution of structural and functional features along the chromosome revealed partitioning correlated with meiotic recombination. Comparative analyses indicated high wheat-specific inter- and intrachromosomal gene duplication activities that are potential sources of variability for adaption. In addition to providing a better understanding of the organization, function, and evolution of a large and polyploid genome, the availability of a high-quality sequence anchored to genetic maps will accelerate the identification of genes underlying important agronomic traits. PMID:25035497

  8. Registration of Warhorse wheat

    Technology Transfer Automated Retrieval System (TEKTRAN)

    'Warhorse' (Reg. No. CV-1096, PI 670157) hard red winter (HRW) wheat (Triticum aestivum L.) was developed and released by the Montana Agricultural Experiment Station in September 2013. Warhorse is of unknown pedigree, derived from a composite of three topcrosses made to the same F1 population in 200...

  9. Registration of ‘Warhorse’ wheat

    Technology Transfer Automated Retrieval System (TEKTRAN)

    ‘Warhorse’ (Reg. No. CV-1096, PI 670157) hard red winter (HRW) wheat (Triticum aestivum L.) was developed and released by the Montana Agricultural Experiment Station in September 2013. Warhorse is of unknown pedigree, derived from a composite of three topcrosses made to the same F1 population in 200...

  10. Physical Mapping Integrated with Syntenic Analysis to Characterize the Gene Space of the Long Arm of Wheat Chromosome 1A

    PubMed Central

    Lucas, Stuart J.; Akp?nar, Bala An?; Kantar, Melda; Weinstein, Zohar; Ayd?no?lu, Fatma; Šafá?, Jan; Šimková, Hana; Frenkel, Zeev; Korol, Abraham; Magni, Federica; Cattonaro, Federica; Vautrin, Sonia; Bellec, Arnaud; Bergès, Hélène; Doležel, Jaroslav; Budak, Hikmet

    2013-01-01

    Background Bread wheat (Triticum aestivum L.) is one of the most important crops worldwide and its production faces pressing challenges, the solution of which demands genome information. However, the large, highly repetitive hexaploid wheat genome has been considered intractable to standard sequencing approaches. Therefore the International Wheat Genome Sequencing Consortium (IWGSC) proposes to map and sequence the genome on a chromosome-by-chromosome basis. Methodology/Principal Findings We have constructed a physical map of the long arm of bread wheat chromosome 1A using chromosome-specific BAC libraries by High Information Content Fingerprinting (HICF). Two alternative methods (FPC and LTC) were used to assemble the fingerprints into a high-resolution physical map of the chromosome arm. A total of 365 molecular markers were added to the map, in addition to 1122 putative unique transcripts that were identified by microarray hybridization. The final map consists of 1180 FPC-based or 583 LTC-based contigs. Conclusions/Significance The physical map presented here marks an important step forward in mapping of hexaploid bread wheat. The map is orders of magnitude more detailed than previously available maps of this chromosome, and the assignment of over a thousand putative expressed gene sequences to specific map locations will greatly assist future functional studies. This map will be an essential tool for future sequencing of and positional cloning within chromosome 1A. PMID:23613713

  11. Analysis of the Endophytic Actinobacterial Population in the Roots of Wheat (Triticum aestivum L.) by Terminal Restriction Fragment Length Polymorphism and Sequencing of 16S rRNA Clones

    Microsoft Academic Search

    Vanessa M. Conn; Christopher M. M. Franco

    2004-01-01

    The endophytic actinobacterial population in the roots of wheat grown in three different soils obtained from the southeast part of South Australia was investigated by terminal restriction fragment length polymorphism (T-RFLP) analysis of the amplified 16S rRNA genes. A new, validated approach was applied to the T-RFLP analysis in order to estimate, to the genus level, the actinobacterial population that

  12. Population Diversity of Yeasts and Lactic Acid Bacteria in Pig Feed Fermented with Whey, Wet Wheat Distillers' Grains, or Water at Different Temperatures?

    PubMed Central

    Olstorpe, Matilda; Lyberg, Karin; Lindberg, Jan Erik; Schnürer, Johan; Passoth, Volkmar

    2008-01-01

    The diversity of populations of yeast and lactic acid bacteria (LAB) in pig feeds fermented at 10, 15, or 20°C was characterized by rRNA gene sequencing of isolates. The feeds consisted of a cereal grain mix blended with wet wheat distillers' grains (WWDG feed), whey (W feed), or tap water (WAT feed). Fermentation proceeded for 5 days without disturbance, followed by 14 days of daily simulated feed outtakes, in which 80% of the contents were replaced with fresh feed mixtures. In WWDG feed, Pichia galeiformis became the dominant yeast species, independent of the fermentation temperature and feed change. The LAB population was dominated by Pediococcus pentosaceus at the start of the fermentation period. After 3 days, the Lactobacillus plantarum population started to increase in feeds at all temperatures. The diversity of LAB increased after the addition of fresh feed components. In W feed, Kluyveromyces marxianus dominated, but after the feed change, the population diversity increased. With increasing fermentation temperatures, there was a shift toward Pichia membranifaciens as the dominant species. L. plantarum was the most prevalent LAB in W feed. The WAT feed had a diverse microbial flora, and the yeast population changed throughout the whole fermentation period. Pichia anomala was the most prevalent yeast species, with increasing occurrence at higher fermentation temperatures. Pediococcus pentosaceus was the most prevalent LAB, but after the feed change, L. plantarum started to proliferate. The present study demonstrates that the species composition in fermented pig feed may vary considerably, even if viable cell counts indicate stable microbial populations. PMID:18223110

  13. Discrimination of the Closely Related A and D Genomes of the Hexaploid Oat Avena sativa L

    Microsoft Academic Search

    Concha Linares; Esther Ferrer; Araceli Fominaya

    1998-01-01

    A satellite DNA sequence, As120a, specific to the A-genome chromosomes in the hexaploid oat, Avena sativa L., was isolated by subcloning a fragment with internal tandem repeats from a plasmid, pAs120, that had been obtained from an Avena strigosa (As genome) genomic library. Southern and in situ hybridization showed that sequences with homology to sequences within pAs120 were dispersed throughout

  14. Eat Wheat!

    ERIC Educational Resources Information Center

    Idaho Wheat Commission, Boise.

    This pamphlet contains puzzles, games, and a recipe designed to teach elementary school pupils about wheat. It includes word games based on the U.S. Department of Agriculture Food Guide Pyramid and on foods made from wheat. The Food Guide Pyramid can be cut out of the pamphlet and assembled as a three-dimensional information source and food guide.…

  15. Wheat Newsletter

    Technology Transfer Automated Retrieval System (TEKTRAN)

    This review was written for readers of the Annual Wheat Newsletter, Volume 53. It summarizes activities on wheat research during 2006 at the U.S. Grain Marketing Research Laboratory (USGMRL). The article includes technical abstracts of research accomplishments from the Grain Quality and Structure ...

  16. Population Dynamics and Metabolite Target Analysis of Lactic Acid Bacteria during Laboratory Fermentations of Wheat and Spelt Sourdoughs?

    PubMed Central

    Van der Meulen, Roel; Scheirlinck, Ilse; Van Schoor, Ann; Huys, Geert; Vancanneyt, Marc; Vandamme, Peter; De Vuyst, Luc

    2007-01-01

    Four laboratory sourdough fermentations, initiated with wheat or spelt flour and without the addition of a starter culture, were prepared over a period of 10 days with daily back-slopping. Samples taken at all refreshment steps were used for determination of the present microbiota. Furthermore, an extensive metabolite target analysis of more than 100 different compounds was performed through a combination of various chromatographic methods including liquid chromatography-mass spectrometry and gas chromatography-mass spectrometry. The establishment of a stable microbial ecosystem occurred through a three-phase evolution within a week, as revealed by both microbiological and metabolite analyses. Strains of Lactobacillus plantarum, Lactobacillus fermentum, Lactobacillus rossiae, Lactobacillus brevis, and Lactobacillus paraplantarum were dominating some of the sourdough ecosystems. Although the heterofermentative L. fermentum was dominating one of the wheat sourdoughs, all other sourdoughs were dominated by a combination of obligate and facultative heterofermentative taxa. Strains of homofermentative species were not retrieved in the stable sourdough ecosystems. Concentrations of sugar and amino acid metabolites hardly changed during the last days of fermentation. Besides lactic acid, ethanol, and mannitol, the production of succinic acid, erythritol, and various amino acid metabolites, such as phenyllactic acid, hydroxyphenyllactic acid, and indolelactic acid, was shown during fermentation. Physiologically, they contributed to the equilibration of the redox balance. The biphasic approach of the present study allowed us to map some of the interactions taking place during sourdough fermentation and helped us to understand the fine-tuned metabolism of lactic acid bacteria, which allows them to dominate a food ecosystem. PMID:17557853

  17. WheatGenome.info: an integrated database and portal for wheat genome information.

    PubMed

    Lai, Kaitao; Berkman, Paul J; Lorenc, Michal Tadeusz; Duran, Chris; Smits, Lars; Manoli, Sahana; Stiller, Jiri; Edwards, David

    2012-02-01

    Bread wheat (Triticum aestivum) is one of the most important crop plants, globally providing staple food for a large proportion of the human population. However, improvement of this crop has been limited due to its large and complex genome. Advances in genomics are supporting wheat crop improvement. We provide a variety of web-based systems hosting wheat genome and genomic data to support wheat research and crop improvement. WheatGenome.info is an integrated database resource which includes multiple web-based applications. These include a GBrowse2-based wheat genome viewer with BLAST search portal, TAGdb for searching wheat second-generation genome sequence data, wheat autoSNPdb, links to wheat genetic maps using CMap and CMap3D, and a wheat genome Wiki to allow interaction between diverse wheat genome sequencing activities. This system includes links to a variety of wheat genome resources hosted at other research organizations. This integrated database aims to accelerate wheat genome research and is freely accessible via the web interface at http://www.wheatgenome.info/. PMID:22009731

  18. EST-derived SSR markers from defined regions of the wheat genome to identify Lophopyrum elongatum specific loci.

    PubMed

    Mullan, Daniel J; Platteter, Amanda; Teakle, Natasha L; Appels, Rudi; Colmer, Timothy D; Anderson, Joseph M; Francki, Michael G

    2005-10-01

    Lophopyrum elongatum, a close relative of wheat, provides a source of novel genes for wheat improvement. Molecular markers were developed to monitor the introgression of L. elongatum chromosome segments into hexaploid wheat. Existing simple sequence repeats (SSRs) derived from genomic libraries were initially screened for detecting L. elongatum loci in wheat, but only 6 of the 163 markers tested were successful. To increase detection of L. elongatum specific loci, 165 SSRs were identified from wheat expressed sequence tags (ESTs), where their chromosomal positions in wheat were known from deletion bin mapping. Detailed sequence analysis identified 41 SSRs within this group as potentially superior in their ability to detect L. elongatum loci. BLASTN alignments were used to position primers within regions of the ESTs that have sequence conservation with at least 1 similar EST from another cereal species. The targeting of primers in this manner enabled 14 L. elongatum markers from 41 wheat ESTs to be identified, whereas only 2 from 124 primers designed in random positions flanking SSRs detected L. elongatum loci. Addition and ditelosomic lines were used to assign all 22 markers to specific chromosome locations in L. elongatum. Nine of these SSR markers were assigned to homoeologous chromosome locations based on their similar position in hexaploid wheat. The remaining markers mapped to other L. elongatum chromosomes indicating a degree of chromosome rearrangements, paralogous sequences and (or) sequence variation between the 2 species. The EST-SSR markers were also used to screen other wheatgrass species indicating further chromosome rearrangements and (or) sequence variation between wheatgrass genomes. This study details methodologies for the generation of SSRs for detecting L. elongatum loci. PMID:16391687

  19. Origin, Migration Routes and Worldwide Population Genetic Structure of the Wheat Yellow Rust Pathogen Puccinia striiformis f.sp. tritici

    PubMed Central

    Ali, Sajid; Gladieux, Pierre; Leconte, Marc; Gautier, Angélique; Justesen, Annemarie F.; Hovmøller, Mogens S.; Enjalbert, Jérôme; de Vallavieille-Pope, Claude

    2014-01-01

    Analyses of large-scale population structure of pathogens enable the identification of migration patterns, diversity reservoirs or longevity of populations, the understanding of current evolutionary trajectories and the anticipation of future ones. This is particularly important for long-distance migrating fungal pathogens such as Puccinia striiformis f.sp. tritici (PST), capable of rapid spread to new regions and crop varieties. Although a range of recent PST invasions at continental scales are well documented, the worldwide population structure and the center of origin of the pathogen were still unknown. In this study, we used multilocus microsatellite genotyping to infer worldwide population structure of PST and the origin of new invasions based on 409 isolates representative of distribution of the fungus on six continents. Bayesian and multivariate clustering methods partitioned the set of multilocus genotypes into six distinct genetic groups associated with their geographical origin. Analyses of linkage disequilibrium and genotypic diversity indicated a strong regional heterogeneity in levels of recombination, with clear signatures of recombination in the Himalayan (Nepal and Pakistan) and near-Himalayan regions (China) and a predominant clonal population structure in other regions. The higher genotypic diversity, recombinant population structure and high sexual reproduction ability in the Himalayan and neighboring regions suggests this area as the putative center of origin of PST. We used clustering methods and approximate Bayesian computation (ABC) to compare different competing scenarios describing ancestral relationship among ancestral populations and more recently founded populations. Our analyses confirmed the Middle East-East Africa as the most likely source of newly spreading, high-temperature-adapted strains; Europe as the source of South American, North American and Australian populations; and Mediterranean-Central Asian populations as the origin of South African populations. Although most geographic populations are not markedly affected by recent dispersal events, this study emphasizes the influence of human activities on recent long-distance spread of the pathogen. PMID:24465211

  20. Origin, migration routes and worldwide population genetic structure of the wheat yellow rust pathogen Puccinia striiformis f.sp. tritici.

    PubMed

    Ali, Sajid; Gladieux, Pierre; Leconte, Marc; Gautier, Angélique; Justesen, Annemarie F; Hovmøller, Mogens S; Enjalbert, Jérôme; de Vallavieille-Pope, Claude

    2014-01-01

    Analyses of large-scale population structure of pathogens enable the identification of migration patterns, diversity reservoirs or longevity of populations, the understanding of current evolutionary trajectories and the anticipation of future ones. This is particularly important for long-distance migrating fungal pathogens such as Puccinia striiformis f.sp. tritici (PST), capable of rapid spread to new regions and crop varieties. Although a range of recent PST invasions at continental scales are well documented, the worldwide population structure and the center of origin of the pathogen were still unknown. In this study, we used multilocus microsatellite genotyping to infer worldwide population structure of PST and the origin of new invasions based on 409 isolates representative of distribution of the fungus on six continents. Bayesian and multivariate clustering methods partitioned the set of multilocus genotypes into six distinct genetic groups associated with their geographical origin. Analyses of linkage disequilibrium and genotypic diversity indicated a strong regional heterogeneity in levels of recombination, with clear signatures of recombination in the Himalayan (Nepal and Pakistan) and near-Himalayan regions (China) and a predominant clonal population structure in other regions. The higher genotypic diversity, recombinant population structure and high sexual reproduction ability in the Himalayan and neighboring regions suggests this area as the putative center of origin of PST. We used clustering methods and approximate Bayesian computation (ABC) to compare different competing scenarios describing ancestral relationship among ancestral populations and more recently founded populations. Our analyses confirmed the Middle East-East Africa as the most likely source of newly spreading, high-temperature-adapted strains; Europe as the source of South American, North American and Australian populations; and Mediterranean-Central Asian populations as the origin of South African populations. Although most geographic populations are not markedly affected by recent dispersal events, this study emphasizes the influence of human activities on recent long-distance spread of the pathogen. PMID:24465211

  1. Quanah Wheat.

    E-print Network

    Atkins, Irvin Milburn

    1951-01-01

    laboratories show that it is satisfactory for the production of bakery flour. BULLETIN 734 IAY 1951 I. M. ATKINS* W INTER WHEAT is grown in Texas on more than five million acres annually and is one of the most important cash crops. Approximately half... Milling and baking characteristics are of major consideration in the development of a new wheat variety, since it must fit into the needs of the trade. Wheat that will make !good bakery flour is in greatest demand because commercial bakeries now supply...

  2. The wheat D-genome HMW-glutenin locus: BAC sequencing, gene distribution, and retrotransposon clusters

    Microsoft Academic Search

    O. D. Anderson; C. Rausch; O. Moullet; E. S. Lagudah

    2003-01-01

    .   A bacterial-artificial-chromosome (BAC) clone from the genome of Triticum tauschii, the D-genome ancestor of hexaploid bread wheat, was sequenced and the presence of the two paralogous x- and y-type high-molecular-weight\\u000a (HMW) glutenin genes of the Glu-D1 locus was confirmed. These two genes occur in the same orientation, are 51,893 bp apart, and the separating DNA includes\\u000a a 31,000-bp cluster of

  3. Homoeologous gene silencing in tissue cultured wheat callus

    PubMed Central

    Bottley, Andrew; Chapman, Natalie H; Koebner, Robert MD

    2008-01-01

    Background In contrast to diploids, most polyploid plant species, which include the hexaploid bread wheat, possess an additional layer of epigenetic complexity. Several studies have demonstrated that polyploids are affected by homoeologous gene silencing, a process in which sub-genomic genomic copies are selectively transcriptionally inactivated. This form of silencing can be tissue specific and may be linked to developmental or stress responses. Results Evidence was sought as to whether the frequency of homoeologous silencing in in vitro cultured wheat callus differ from that in differentiated organs, given that disorganized cells are associated with a globally lower level of DNA methylation. Using a reverse transcription PCR (RT-PCR) single strand conformation polymorphism (SSCP) platform to detect the pattern of expression of 20 homoeologous sets of single-copy genes known to be affected by this form of silencing in the root and/or leaf, we observed no silencing in any of the wheat callus tissue tested. Conclusion Our results suggest that much of the homoeologous silencing observed in differentiated tissues is probably under epigenetic control, rather than being linked to genomic instability arising from allopolyploidization. This study reinforces the notion of plasticity in the wheat epi-genome. PMID:18928533

  4. IMPROVING BIOLOGICAL CONTROL OF AN INVASIVE PEST WITH MOLECULAR PHYLOGEOGRAPHIC AND POPULATION GENETIC APPROACHES: THE WHEAT STEM SAWFLY, CEPHUS CINCTUS NORTON, (HYMENOPTERA : CEPHIDAE) AS A CASE STUDY

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The wheat stem sawfly (WSS), Cephus cinctus Norton (Hymenoptera: Cephidae) has become a chronic pest of wheat in the semi-arid steppe region of the North American Great Plains. To develop a more general and conceptual framework with predictive value for the biological control of this pest, it is imp...

  5. Association between simple sequence repeat-rich chromosome regions and intergenomic translocation breakpoints in natural populations of allopolyploid wild wheats

    PubMed Central

    Molnár, István; Cifuentes, Marta; Schneider, Annamária; Benavente, Elena; Molnár-Láng, Márta

    2011-01-01

    Background and Aims Repetitive DNA sequences are thought to be involved in the formation of chromosomal rearrangements. The aim of this study was to analyse the distribution of microsatellite clusters in Aegilops biuncialis and Aegilops geniculata, and its relationship with the intergenomic translocations in these allotetraploid species, wild genetic resources for wheat improvement. Methods The chromosomal localization of (ACG)n and (GAA)n microsatellite sequences in Ae. biuncialis and Ae. geniculata and in their diploid progenitors Aegilops comosa and Aegilops umbellulata was investigated by sequential in situ hybridization with simple sequence repeat (SSR) probes and repeated DNA probes (pSc119·2, Afa family and pTa71) and by dual-colour genomic in situ hybridization (GISH). Thirty-two Ae. biuncialis and 19 Ae. geniculata accessions were screened by GISH for intergenomic translocations, which were further characterized by fluorescence in situ hybridization and GISH. Key Results Single pericentromeric (ACG)n signals were localized on most U and on some M genome chromosomes, whereas strong pericentromeric and several intercalary and telomeric (GAA)n sites were observed on the Aegilops chromosomes. Three Ae. biuncialis accessions carried 7Ub–7Mb reciprocal translocations and one had a 7Ub–1Mb rearrangement, while two Ae. geniculata accessions carried 7Ug–1Mg or 5Ug–5Mg translocations. Conspicuous (ACG)n and/or (GAA)n clusters were located near the translocation breakpoints in eight of the ten translocated chromosomes analysed, SSR bands and breakpoints being statistically located at the same chromosomal site in six of them. Conclusions Intergenomic translocation breakpoints are frequently mapped to SSR-rich chromosomal regions in the allopolyploid species examined, suggesting that microsatellite repeated DNA sequences might facilitate the formation of those chromosomal rearrangements. The (ACG)n and (GAA)n SSR motifs serve as additional chromosome markers for the karyotypic analysis of UM genome Aegilops species. PMID:21036694

  6. [Use of the common winter wheat homozygous population for genetic analysis of beta-amylase and evaluation of its aggregation ability].

    PubMed

    Netsvetaev, V P; Akinshina, O V; Bondarenko, L S

    2014-11-01

    We investigated a self-pollinated homozygous population of common winter wheat, F(-> ?) 24/04 x Odesskaya krasnokolosaya, for variants of beta-amylase and the aggregation ability of the protein complex of weevil via disulfide bonds. It was found that variation in the electrophoretic types of this enzyme was due to four isoenzymes. Two of them (a and b) are doubled and controlled by separate loci with independent inheritance. Isoenzyme c was due to three dominant factors, and four loci were responsible for d. Analysis of the number of -S-S-bonds of five genotypes, which were harvested in 2013 and differed in the types of beta-amylase, showed that some of them were significantly different from others in this indicator. In general, the samples were grouped by the type of this enzyme, forming the following continuous series with respect to aggregation ability: I ? B ? F ? D ? G or 59.13 ± 3.18 ? 56.65 ± 2.46 ? 52.54 ± 2.24 ? 50.16 ± 1.67 ? 48.63 ± 6.25 of cond. units. Significant differences were observed for this property between groups B > D and I > D. Therefore, genotypes having types I and B have a positive influence on the rheological properties of dough. PMID:25739283

  7. Accelerated Senescence and Enhanced Disease Resistance in Hybrid Chlorosis Lines Derived from Interspecific Crosses between Tetraploid Wheat and Aegilops tauschii

    PubMed Central

    Tosa, Yukio; Yoshida, Kentaro; Park, Pyoyun; Takumi, Shigeo

    2015-01-01

    Hybrid chlorosis, a type of hybrid incompatibility, has frequently been reported in inter- and intraspecific crosses of allopolyploid wheat. In a previous study, we reported some types of growth abnormalities such as hybrid necrosis and observed hybrid chlorosis with mild or severe abnormalities in wheat triploids obtained in crosses between tetraploid wheat cultivar Langdon and four Ae. tauschii accessions and in their derived synthetic hexaploids. However, the molecular mechanisms underlying hybrid chlorosis are not well understood. Here, we compared cytology and gene expression in leaves to characterize the abnormal growth in wheat synthetics showing mild and severe chlorosis. In addition, we compared disease resistance to wheat blast fungus. In total 55 and 105 genes related to carbohydrate metabolism and 53 and 89 genes for defense responses were markedly up-regulated in the mild and severe chlorosis lines, respectively. Abnormal chloroplasts formed in the mesophyll cells before the leaves yellowed in the hybrid chlorosis lines. The plants with mild chlorosis showed increased resistance to wheat blast and powdery mildew fungi, although significant differences only in two, third internode length and maturation time, out of the examined agricultural traits were found between the wild type and plants showing mild chlorosis. These observations suggest that senescence might be accelerated in hybrid chlorosis lines of wheat synthetics. Moreover, in wheat synthetics showing mild chlorosis, the negative effects on biomass can be minimized, and they may show substantial fitness under pathogen-polluted conditions. PMID:25806790

  8. Accelerated senescence and enhanced disease resistance in hybrid chlorosis lines derived from interspecific crosses between tetraploid wheat and Aegilops tauschii.

    PubMed

    Nakano, Hiroki; Mizuno, Nobuyuki; Tosa, Yukio; Yoshida, Kentaro; Park, Pyoyun; Takumi, Shigeo

    2015-01-01

    Hybrid chlorosis, a type of hybrid incompatibility, has frequently been reported in inter- and intraspecific crosses of allopolyploid wheat. In a previous study, we reported some types of growth abnormalities such as hybrid necrosis and observed hybrid chlorosis with mild or severe abnormalities in wheat triploids obtained in crosses between tetraploid wheat cultivar Langdon and four Ae. tauschii accessions and in their derived synthetic hexaploids. However, the molecular mechanisms underlying hybrid chlorosis are not well understood. Here, we compared cytology and gene expression in leaves to characterize the abnormal growth in wheat synthetics showing mild and severe chlorosis. In addition, we compared disease resistance to wheat blast fungus. In total 55 and 105 genes related to carbohydrate metabolism and 53 and 89 genes for defense responses were markedly up-regulated in the mild and severe chlorosis lines, respectively. Abnormal chloroplasts formed in the mesophyll cells before the leaves yellowed in the hybrid chlorosis lines. The plants with mild chlorosis showed increased resistance to wheat blast and powdery mildew fungi, although significant differences only in two, third internode length and maturation time, out of the examined agricultural traits were found between the wild type and plants showing mild chlorosis. These observations suggest that senescence might be accelerated in hybrid chlorosis lines of wheat synthetics. Moreover, in wheat synthetics showing mild chlorosis, the negative effects on biomass can be minimized, and they may show substantial fitness under pathogen-polluted conditions. PMID:25806790

  9. The Localization and Expression of the Class II Starch Synthases of Wheat1

    PubMed Central

    Li, Zhongyi; Chu, Xiusheng; Mouille, Gregory; Yan, Liuling; Kosar-Hashemi, Behjat; Hey, Sandra; Napier, Johnathan; Shewry, Peter; Clarke, Bryan; Appels, Rudi; Morell, Matthew K.; Rahman, Sadequr

    1999-01-01

    The starch granules of hexaploid wheat (Triticum aestivum) contain a group of three proteins known as SGP-1 (starch granule protein-1) proteins, which have apparent molecular masses of 100, 108, and 115 kD. The nature and role of these proteins has not been defined previously. We demonstrate that these polypeptides are starch synthases that are present in both the starch granule and the soluble fraction at the early stages of wheat endosperm development, but that are exclusively granule bound at mid and late endosperm development. A partial cDNA clone encoding a fragment of the 100-kD protein was obtained by screening a wheat endosperm cDNA expression library using monoclonal antibodies. Three classes of cDNA were subsequently isolated from a wheat endosperm cDNA library by nucleic acid hybridization and were shown to encode the 100-, 108-, and 115-kD proteins. The cDNA sequences are highly homologous to class II starch synthases and have the highest homology with the maize SSIIa (starch synthase IIa) gene. mRNA for the SGP-1 proteins was detected in the leaf, pre-anthesis florets, and endosperm of wheat and is highly expressed in the leaf and in the grain during the early to mid stages of development. We discuss the roles of the SGP-1 proteins in starch biosynthesis in wheat. PMID:10444098

  10. The localization and expression of the class II starch synthases of wheat.

    PubMed

    Li, Z; Chu, X; Mouille, G; Yan, L; Kosar-Hashemi, B; Hey, S; Napier, J; Shewry, P; Clarke, B; Appels, R; Morell, M K; Rahman, S

    1999-08-01

    The starch granules of hexaploid wheat (Triticum aestivum) contain a group of three proteins known as SGP-1 (starch granule protein-1) proteins, which have apparent molecular masses of 100, 108, and 115 kD. The nature and role of these proteins has not been defined previously. We demonstrate that these polypeptides are starch synthases that are present in both the starch granule and the soluble fraction at the early stages of wheat endosperm development, but that are exclusively granule bound at mid and late endosperm development. A partial cDNA clone encoding a fragment of the 100-kD protein was obtained by screening a wheat endosperm cDNA expression library using monoclonal antibodies. Three classes of cDNA were subsequently isolated from a wheat endosperm cDNA library by nucleic acid hybridization and were shown to encode the 100-, 108-, and 115-kD proteins. The cDNA sequences are highly homologous to class II starch synthases and have the highest homology with the maize SSIIa (starch synthase IIa) gene. mRNA for the SGP-1 proteins was detected in the leaf, pre-anthesis florets, and endosperm of wheat and is highly expressed in the leaf and in the grain during the early to mid stages of development. We discuss the roles of the SGP-1 proteins in starch biosynthesis in wheat. PMID:10444098

  11. Biosystematic study of hexaploids Elymus tschimganicus and E. glaucissimus. I. Morphology and genomic constitution.

    PubMed

    Jensen, K B; Liu, Z W; Lu, B R; Solamon, B

    1994-05-01

    Elymus tschimganicus and E. glaucissimus are hexaploids (2n = 6x = 42) that inhabit stony slopes and swales in the middle and upper mountain belts of Central Asia. Chromosome pairing at metaphase I in E. tschimganicus and E. glaucissimus was typical of other Elymus hexaploids, averaging 20.94 and 20.98 bivalents per cell, respectively. Meiotic pairing of tetraploid hybrids derived by crossing E. tschimganicus and E. glaucissimus with P. spicata (2n = 2x = 14; genome = SS) averaged 4.97 and 4.90 bivalents per cell respectively, indicating the presence of the S genome in the target taxa. Pentaploid hybrids derived by crossing E. tschimganicus and E. glaucissimus with tetraploid analyzer species E. mutabilis and E. sibiricus (2n = 4x = 28; genome = SSHH) had mean bivalent frequencies of 5.61 and 4.64 respectively, suggesting the absence of the H genome in the target taxa. Mean bivalent associations were similar among hybrids derived by crossing the target taxa with E. nevski (2n = 4x = 28; genome = SSYY), which averaged 10.61 and 11.42 bivalents, respectively, suggesting the presence of the Y genome in E. tschimganicus and E. glaucissimus. Based on chromosome pairing in the hybrids, the genomic formula for both E. tschimganicus and E. glaucissimus should be SSSSYY. PMID:8069464

  12. Ecological and molecular investigation of wheat bulb fly (Delia coarctata, Fallén, Diptera: Anthomyiidae) for the advancement of population monitoring and control methodologies 

    E-print Network

    Rogers, Craig David

    2012-06-22

    Wheat bulb fly (WBF) (Delia coarctata, Fallén, Diptera: Anthomyiidae) is a pest of commercial importance in cereal crops. Control is dependent on organophosphates some of which are restricted in the UK, while current ...

  13. DETERMINATION OF PLOIDY LEVELS OF SOME POPULATIONS OF AGROPYRON CRISTATUM (POACEAE) IN IRAN BY FLOW CYTOMETRY

    Microsoft Academic Search

    M. YOUSOFI; Payam Noor

    Flow cytometry (FCM) was used to determine the ploidy levels of six different populations of Agropyron cristatum (L.) Gaertn. (Poaceae) in Iran, using a diploid cultivated barley (Hordeum vulgare L.) as an internal reference. According to flow cytometric data, tetraploid (2n = ± 28) and hexaploid (2n = ± 42) levels were detected among the examined populations and these results

  14. Recurrent Deletions of Puroindoline Genes at the Grain Hardness Locus in Four Independent Lineages of Polyploid Wheat1[W][OA

    PubMed Central

    Li, Wanlong; Huang, Li; Gill, Bikram S.

    2008-01-01

    Polyploidy is known to induce numerous genetic and epigenetic changes but little is known about their physiological bases. In wheat, grain texture is mainly determined by the Hardness (Ha) locus consisting of genes Puroindoline a (Pina) and b (Pinb). These genes are conserved in diploid progenitors but were deleted from the A and B genomes of tetraploid Triticum turgidum (AB). We now report the recurrent deletions of Pina-Pinb in other lineages of polyploid wheat. We analyzed the Ha haplotype structure in 90 diploid and 300 polyploid accessions of Triticum and Aegilops spp. Pin genes were conserved in all diploid species and deletion haplotypes were detected in all polyploid Triticum and most of the polyploid Aegilops spp. Two Pina-Pinb deletion haplotypes were found in hexaploid wheat (Triticum aestivum; ABD). Pina and Pinb were eliminated from the G genome, but maintained in the A genome of tetraploid Triticum timopheevii (AG). Subsequently, Pina and Pinb were deleted from the A genome but retained in the Am genome of hexaploid Triticum zhukovskyi (AmAG). Comparison of deletion breakpoints demonstrated that the Pina-Pinb deletion occurred independently and recurrently in the four polyploid wheat species. The implications of Pina-Pinb deletions for polyploid-driven evolution of gene and genome and its possible physiological significance are discussed. PMID:18024553

  15. Wheat Diseases Atlas.

    E-print Network

    McCoy, Norman L.; Berry, Robert W.

    1982-01-01

    . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8 Barley Yellow Dwarf (Virus) . . . . . . . . . . . . . . . . 9 Wheat Streak Mosaic (Virus) . . . . . . . . . . . . . . . IO Wheat (Soilborne) Mosaic (Virus) . . . . . . . . . . . IO STEM AND HEAD DISEASES .............. II Glume Blotch... . . . . . . . . . . . . . . . . . . . . . . . . . . . I5 Yellow Berry . . . . . . . . . . . . . . . . . . . . . . . . . . . . . I5 Storage Molds . . . . . . . . . . . . . . . . . . . . . . . . . . . . I6 HERBICIDE INJURY TO WHEAT . . . . . . . . . . . 16 Low Fertility...

  16. Determination of the linkage relationships and the gene-centromere genetic distances for endopeptidase structural genes in hexaploid wheat

    E-print Network

    McMillin, David Edwin

    1977-01-01

    . Pl of cross No. 2 ll. Fl of cross No. 3 12. Pl of cross No. 5 13. Fl of cross No. 6 14. Fl of cross No. 8 15. Fl of crass No. 9 Chinese Chinese Chinese Chinese Chinese Chi. . ese Chinese Chinese Chinese Chinese Chinese Chinese Chinese... Chinese Spring ditelo 7AL and 78L. The Fl progeny were backcrossed to Chinese Spring. Nine zymogram phenotypes were observed from e"ch cross. An offspring from the 7BL backcross was found to have 41 chromosomes; from the analysis of this offspring a...

  17. Sequencing of chloroplast genomes from wheat, barley, rye and their relatives provides a detailed insight into the evolution of the Triticeae tribe.

    PubMed

    Middleton, Christopher P; Senerchia, Natacha; Stein, Nils; Akhunov, Eduard D; Keller, Beat; Wicker, Thomas; Kilian, Benjamin

    2014-01-01

    Using Roche/454 technology, we sequenced the chloroplast genomes of 12 Triticeae species, including bread wheat, barley and rye, as well as the diploid progenitors and relatives of bread wheat Triticum urartu, Aegilops speltoides and Ae. tauschii. Two wild tetraploid taxa, Ae. cylindrica and Ae. geniculata, were also included. Additionally, we incorporated wild Einkorn wheat Triticum boeoticum and its domesticated form T. monococcum and two Hordeum spontaneum (wild barley) genotypes. Chloroplast genomes were used for overall sequence comparison, phylogenetic analysis and dating of divergence times. We estimate that barley diverged from rye and wheat approximately 8-9 million years ago (MYA). The genome donors of hexaploid wheat diverged between 2.1-2.9 MYA, while rye diverged from Triticum aestivum approximately 3-4 MYA, more recently than previously estimated. Interestingly, the A genome taxa T. boeoticum and T. urartu were estimated to have diverged approximately 570,000 years ago. As these two have a reproductive barrier, the divergence time estimate also provides an upper limit for the time required for the formation of a species boundary between the two. Furthermore, we conclusively show that the chloroplast genome of hexaploid wheat was contributed by the B genome donor and that this unknown species diverged from Ae. speltoides about 980,000 years ago. Additionally, sequence alignments identified a translocation of a chloroplast segment to the nuclear genome which is specific to the rye/wheat lineage. We propose the presented phylogeny and divergence time estimates as a reference framework for future studies on Triticeae. PMID:24614886

  18. Sequencing of Chloroplast Genomes from Wheat, Barley, Rye and Their Relatives Provides a Detailed Insight into the Evolution of the Triticeae Tribe

    PubMed Central

    Middleton, Christopher P.; Senerchia, Natacha; Stein, Nils; Akhunov, Eduard D.; Keller, Beat

    2014-01-01

    Using Roche/454 technology, we sequenced the chloroplast genomes of 12 Triticeae species, including bread wheat, barley and rye, as well as the diploid progenitors and relatives of bread wheat Triticum urartu, Aegilops speltoides and Ae. tauschii. Two wild tetraploid taxa, Ae. cylindrica and Ae. geniculata, were also included. Additionally, we incorporated wild Einkorn wheat Triticum boeoticum and its domesticated form T. monococcum and two Hordeum spontaneum (wild barley) genotypes. Chloroplast genomes were used for overall sequence comparison, phylogenetic analysis and dating of divergence times. We estimate that barley diverged from rye and wheat approximately 8–9 million years ago (MYA). The genome donors of hexaploid wheat diverged between 2.1–2.9 MYA, while rye diverged from Triticum aestivum approximately 3–4 MYA, more recently than previously estimated. Interestingly, the A genome taxa T. boeoticum and T. urartu were estimated to have diverged approximately 570,000 years ago. As these two have a reproductive barrier, the divergence time estimate also provides an upper limit for the time required for the formation of a species boundary between the two. Furthermore, we conclusively show that the chloroplast genome of hexaploid wheat was contributed by the B genome donor and that this unknown species diverged from Ae. speltoides about 980,000 years ago. Additionally, sequence alignments identified a translocation of a chloroplast segment to the nuclear genome which is specific to the rye/wheat lineage. We propose the presented phylogeny and divergence time estimates as a reference framework for future studies on Triticeae. PMID:24614886

  19. Evidence for AEGILOPS SHARONENSIS Eig as the Donor of the B Genome of Wheat

    PubMed Central

    Kushnir, U.; Halloran, G. M.

    1981-01-01

    A number of lines of evidence are advanced for the candidacy of Aegilops sharonensis Eig as the donor of the B genome of wheat. The cytoplasm of Ae. sharonensis is compatible with tetraploid wheat Triticum turgidum dicoccoides, as evidenced by the high level of chromosome pairing and fertility of the amphiploid Ae. sharonensis x T. turgidum dicoccoides. Ae. sharonensis chromosomes exhibit high levels of pairing with those of the B genome of wheat in hybrids with Ph-deficient hexaploid wheat and low levels of homoeologous pairing with T. monococcum chromosomes.——The amphidiploid between Ae. sharonensis and T. monococcum is very similar to T. turgidum dicoccoides in spike, spikelet and grain morphology. The karyotype of Ae. sharonensis resembles more closely that of extrapolated B genome karyotypes of wheat than do the karyotypes of other proposed B-genome donor species of Aegilops. Because of distinctiveness in cytological affinity and karyotype morphology between Ae. sharonensis and Ae. longissima, a separate genome symbol Ssh is proposed for the former species. PMID:17249127

  20. A Chromosome Bin Map of 2148 Expressed Sequence Tag Loci of Wheat Homoeologous Group 7

    PubMed Central

    Hossain, K. G.; Kalavacharla, V.; Lazo, G. R.; Hegstad, J.; Wentz, M. J.; Kianian, P. M. A.; Simons, K.; Gehlhar, S.; Rust, J. L.; Syamala, R. R.; Obeori, K.; Bhamidimarri, S.; Karunadharma, P.; Chao, S.; Anderson, O. D.; Qi, L. L.; Echalier, B.; Gill, B. S.; Linkiewicz, A. M.; Ratnasiri, A.; Dubcovsky, J.; Akhunov, E. D.; Dvo?ák, J.; Miftahudin; Ross, K.; Gustafson, J. P.; Radhawa, H. S.; Dilbirligi, M.; Gill, K. S.; Peng, J. H.; Lapitan, N. L. V.; Greene, R. A.; Bermudez-Kandianis, C. E.; Sorrells, M. E.; Feril, O.; Pathan, M. S.; Nguyen, H. T.; Gonzalez-Hernandez, J. L.; Conley, E. J.; Anderson, J. A.; Choi, D. W.; Fenton, D.; Close, T. J.; McGuire, P. E.; Qualset, C. O.; Kianian, S. F.

    2004-01-01

    The objectives of this study were to develop a high-density chromosome bin map of homoeologous group 7 in hexaploid wheat (Triticum aestivum L.), to identify gene distribution in these chromosomes, and to perform comparative studies of wheat with rice and barley. We mapped 2148 loci from 919 EST clones onto group 7 chromosomes of wheat. In the majority of cases the numbers of loci were significantly lower in the centromeric regions and tended to increase in the distal regions. The level of duplicated loci in this group was 24% with most of these loci being localized toward the distal regions. One hundred nineteen EST probes that hybridized to three fragments and mapped to the three group 7 chromosomes were designated landmark probes and were used to construct a consensus homoeologous group 7 map. An additional 49 probes that mapped to 7AS, 7DS, and the ancestral translocated segment involving 7BS also were designated landmarks. Landmark probe orders and comparative maps of wheat, rice, and barley were produced on the basis of corresponding rice BAC/PAC and genetic markers that mapped on chromosomes 6 and 8 of rice. Identification of landmark ESTs and development of consensus maps may provide a framework of conserved coding regions predating the evolution of wheat genomes. PMID:15514045

  1. Genetic transformation of mature embryos of bread (T. aestivum) and pasta (T. durum) wheat genotypes.

    PubMed

    Moghaieb, Reda E A; El-Arabi, Nagwa I; Momtaz, Osama A; Youssef, Sawsan S; Soliman, Mohamed H

    2010-01-01

    The objective of the present study is to develop an efficient protocol for regeneration of transgenic wheat plants using Agrobacterium- mediated transformation of mature embryos of hexaploid bread wheat (Triticum aestivum) and tetraploid pasta wheat (Triticum durum). The data indicated that embryogenic calli were formed within 7 days in the presence of 2 mgl-1 2,4-D. Adventitious shoots emerged from the embryonic calli in the presence of 2 mgl-1 BA. Shoot regeneration frequency varied between wheat cultivars according to their genetic background differences. Regeneration frequency was higher in the cultivar Gemmiza 10 (95 %) compared with the other cultivars tested. Mature embryos derived callus of the cultivars Gemmiza 10 and Gemmiza 9 were co-cultivated with A. tumefaciens strain LBA4404 harboring a binary vector pBI-121 containing the neomycin phosphotransferase-II gene (npt-II). The resulted putative transgenic plantlets were able to grow on kanamycin containing medium. A successful integration of the transgene was confirmed by analyzing the T0 plantlets using Southern hybridization and PCR amplification. The gus gene expression can be detected only in the transgenic plants. The reported protocol is reproducible and can be used to regenerate transgenic wheat plants expressing the genes present in A. tumifaciens binary vectors. PMID:21865876

  2. Functional characterisation of wheat Pgip genes reveals their involvement in the local response to wounding.

    PubMed

    Janni, M; Bozzini, T; Moscetti, I; Volpi, C; D'Ovidio, R

    2013-11-01

    Polygalacturonase-inhibiting proteins (PGIPs) are cell wall leucine-rich repeat (LRR) proteins involved in plant defence. The hexaploid wheat (Triticum aestivum, genome AABBDD) genome contains one Pgip gene per genome. Tapgip1 (B genome) and Tapgip2 (D genome) are expressed in all tissues, whereas Tapgip3 (A genome) is inactive because of a long terminal repeat, Copia retrotransposon insertion within the coding region. To verify whether Tapgip1 and Tapgip2 encode active PGIPs and are involved in the wheat defence response, we expressed them transiently and analysed their expression under stress conditions. Neither TaPGIP1 nor TaPGIP2 showed inhibition activity in vitro against fungal polygalacturonases. Moreover, a wheat genotype (T. turgidum ssp. dicoccoides) lacking active homologues of Tapgip1 or Tapgip2 possesses PGIP activity. At transcript level, Tapgip1 and Tapgip2 were both up-regulated after fungal infection and strongly induced following wounding. This latter result has been confirmed in transgenic wheat plants expressing the ?-glucuronidase (GUS) gene under control of the 5'-flanking region of Tdpgip1, a homologue of Tapgip1 with an identical sequence. Strong and transient GUS staining was mainly restricted to the damaged tissues and was not observed in adjacent tissues. Taken together, these results suggest that Tapgips and their homologues are involved in the wheat defence response by acting at the site of the lesion caused by pathogen infection. PMID:23574379

  3. Aegilops tauschii draft genome sequence reveals a gene repertoire for wheat adaptation.

    PubMed

    Jia, Jizeng; Zhao, Shancen; Kong, Xiuying; Li, Yingrui; Zhao, Guangyao; He, Weiming; Appels, Rudi; Pfeifer, Matthias; Tao, Yong; Zhang, Xueyong; Jing, Ruilian; Zhang, Chi; Ma, Youzhi; Gao, Lifeng; Gao, Chuan; Spannagl, Manuel; Mayer, Klaus F X; Li, Dong; Pan, Shengkai; Zheng, Fengya; Hu, Qun; Xia, Xianchun; Li, Jianwen; Liang, Qinsi; Chen, Jie; Wicker, Thomas; Gou, Caiyun; Kuang, Hanhui; He, Genyun; Luo, Yadan; Keller, Beat; Xia, Qiuju; Lu, Peng; Wang, Junyi; Zou, Hongfeng; Zhang, Rongzhi; Xu, Junyang; Gao, Jinlong; Middleton, Christopher; Quan, Zhiwu; Liu, Guangming; Wang, Jian; Yang, Huanming; Liu, Xu; He, Zhonghu; Mao, Long; Wang, Jun

    2013-04-01

    About 8,000 years ago in the Fertile Crescent, a spontaneous hybridization of the wild diploid grass Aegilops tauschii (2n = 14; DD) with the cultivated tetraploid wheat Triticum turgidum (2n = 4x = 28; AABB) resulted in hexaploid wheat (T. aestivum; 2n = 6x = 42; AABBDD). Wheat has since become a primary staple crop worldwide as a result of its enhanced adaptability to a wide range of climates and improved grain quality for the production of baker's flour. Here we describe sequencing the Ae. tauschii genome and obtaining a roughly 90-fold depth of short reads from libraries with various insert sizes, to gain a better understanding of this genetically complex plant. The assembled scaffolds represented 83.4% of the genome, of which 65.9% comprised transposable elements. We generated comprehensive RNA-Seq data and used it to identify 43,150 protein-coding genes, of which 30,697 (71.1%) were uniquely anchored to chromosomes with an integrated high-density genetic map. Whole-genome analysis revealed gene family expansion in Ae.?tauschii of agronomically relevant gene families that were associated with disease resistance, abiotic stress tolerance and grain quality. This draft genome sequence provides insight into the environmental adaptation of bread wheat and can aid in defining the large and complicated genomes of wheat species. PMID:23535592

  4. Tan spot susceptibility governed by the Tsn1 locus and race-nonspecific resistance quantitative trait loci in a population derived from the wheat lines Salamouni and Katepwa

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Wheat-tan spot interactions are known to have an inverse gene-for-gene relationship where pathogen-produced necrotrophic effectors are recognized by host sensitivity genes to cause susceptibility. However, broad-spectrum non race-specific resistance quantitative trait loci (QTL) that do not conform...

  5. Analysis of agronomic and domestication traits in a durum x cultivated emmer wheat population using a high-density single nucleotide polymorphism-based linkage map

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Cultivated emmer wheat (Triticum turgidum ssp. dicoccum) is tetraploid and considered one of the eight founder crops that spawned the Agricultural Revolution about 10,000 years ago. Cultivated emmer has non-free-threshing seed and a somewhat fragile rachis, but mutations in genes governing these an...

  6. Inheritance of allozymes from seed tissues of the hexaploid gymnosperm, Sequoia sempervirens (D. Don) Endl. (Coast redwood)

    Microsoft Academic Search

    Deborah L Rogers

    1997-01-01

    Coast redwood, Sequoia sempervirens, is a hexaploid gymnosperm of putative autoallopolyploid origin. In this first study of allozymes from the seed tissues of Coast redwood, six enzyme systems were examined in the megagametophyte and embryo tissues of nine control-pollinated (full-sib) families. Megagametophyte segregation patterns reflected considerable within-family segregation and a meiotic process that is consistent with hexasomic segregation. The array

  7. Partial characterization of glutathione S-transferases from wheat (Triticum spp.) and purification of a safener-induced glutathione S-transferase from Triticum tauschii.

    PubMed Central

    Riechers, D E; Irzyk, G P; Jones, S S; Fuerst, E P

    1997-01-01

    Hexaploid wheat (Triticum aestivum L.) has very low constitutive glutathione S-transferase (GST) activity when assayed with the chloroacetamide herbicide dimethenamid as a substrate, which may account for its low tolerance to dimethenamid in the field. Treatment of seeds with the herbicide safener fluxofenim increased the total GST activity extracted from T. aestivum shoots 9-fold when assayed with dimethenamid as a substrate, but had no effect on glutathione levels. Total GST activity in crude protein extracts from T. aestivum, Triticum durum, and Triticum tauschii was separated into several component GST activities by anion-exchange fast-protein liquid chromatography. These activities (isozymes) differed with respect to their activities toward dimethenamid or 1-chloro-2,4-dinitrobenzene as substrates and in their levels of induction by safener treatment. A safener-induced GST isozyme was subsequently purified by anion-exchange and affinity chromatography from etiolated shoots of the diploid wheat species T. tauschii (a progenitor of hexaploid wheat) treated with the herbicide safener cloquintocet-mexyl. The isozyme bound to a dimethenamid-affinity column and had a subunit molecular mass of 26 kD based on sodium dodecyl sulfate-polyacrylamide gel electrophoresis. The purified enzyme (designated GST TSI-1) was recognized by an antiserum raised against a mixture of maize (Zea mays) GSTs. Amino acid sequences obtained from protease-digested GST TSI-1 had significant homology with the safener-inducible maize GST V and two auxin-regulated tobacco (Nicotiana tabacum) GST isozymes. PMID:9276955

  8. Partial characterization of glutathione S-transferases from wheat (Triticum spp.) and purification of a safener-induced glutathione S-transferase from Triticum tauschii.

    PubMed

    Riechers, D E; Irzyk, G P; Jones, S S; Fuerst, E P

    1997-08-01

    Hexaploid wheat (Triticum aestivum L.) has very low constitutive glutathione S-transferase (GST) activity when assayed with the chloroacetamide herbicide dimethenamid as a substrate, which may account for its low tolerance to dimethenamid in the field. Treatment of seeds with the herbicide safener fluxofenim increased the total GST activity extracted from T. aestivum shoots 9-fold when assayed with dimethenamid as a substrate, but had no effect on glutathione levels. Total GST activity in crude protein extracts from T. aestivum, Triticum durum, and Triticum tauschii was separated into several component GST activities by anion-exchange fast-protein liquid chromatography. These activities (isozymes) differed with respect to their activities toward dimethenamid or 1-chloro-2,4-dinitrobenzene as substrates and in their levels of induction by safener treatment. A safener-induced GST isozyme was subsequently purified by anion-exchange and affinity chromatography from etiolated shoots of the diploid wheat species T. tauschii (a progenitor of hexaploid wheat) treated with the herbicide safener cloquintocet-mexyl. The isozyme bound to a dimethenamid-affinity column and had a subunit molecular mass of 26 kD based on sodium dodecyl sulfate-polyacrylamide gel electrophoresis. The purified enzyme (designated GST TSI-1) was recognized by an antiserum raised against a mixture of maize (Zea mays) GSTs. Amino acid sequences obtained from protease-digested GST TSI-1 had significant homology with the safener-inducible maize GST V and two auxin-regulated tobacco (Nicotiana tabacum) GST isozymes. PMID:9276955

  9. A spider population in flux: selection and abandonment of artificial web-sites and the importance of intraspecific interactions in Lephthyphantes tenuis (Araneae: Linyphiidae) in wheat

    Microsoft Academic Search

    Ferenc Samu; Keith D. Sunderland; Chris J. Topping; John S. Fenlon

    1996-01-01

    Lepthyphantes tenuis, a small sheet-webbuilding linyphiid spider is one of the most abundant spider species of cereal fields in Europe. In the present study we examined the process of web-site selection and web-site tenacity by adult females of this species in a winter wheat field. Spiders were selective in their choice of web-site. Different immigration rates into various manipulated web-sites,

  10. Exploring and Mobilizing the Gene Bank Biodiversity for Wheat Improvement

    PubMed Central

    Sehgal, Deepmala; Vikram, Prashant; Sansaloni, Carolina Paola; Ortiz, Cynthia; Pierre, Carolina Saint; Payne, Thomas; Ellis, Marc; Amri, Ahmed; Petroli, César Daniel; Wenzl, Peter; Singh, Sukhwinder

    2015-01-01

    Identifying and mobilizing useful genetic variation from germplasm banks to breeding programs is an important strategy for sustaining crop genetic improvement. The molecular diversity of 1,423 spring bread wheat accessions representing major global production environments was investigated using high quality genotyping-by-sequencing (GBS) loci, and gene-based markers for various adaptive and quality traits. Mean diversity index (DI) estimates revealed synthetic hexaploids to be genetically more diverse (DI= 0.284) than elites (DI = 0.267) and landraces (DI = 0.245). GBS markers discovered thousands of new SNP variations in the landraces which were well known to be adapted to drought (1273 novel GBS SNPs) and heat (4473 novel GBS SNPs) stress environments. This may open new avenues for pre-breeding by enriching the elite germplasm with novel alleles for drought and heat tolerance. Furthermore, new allelic variation for vernalization and glutenin genes was also identified from 47 landraces originating from Iraq, Iran, India, Afghanistan, Pakistan, Uzbekistan and Turkmenistan. The information generated in the study has been utilized to select 200 diverse gene bank accessions to harness their potential in pre-breeding and for allele mining of candidate genes for drought and heat stress tolerance, thus channeling novel variation into breeding pipelines. This research is part of CIMMYT’s ongoing ‘Seeds of Discovery’ project visioning towards the development of high yielding wheat varieties that address future challenges from climate change. PMID:26176697

  11. Reproduction and development of Russian wheat aphid biotype 2 on crested wheatgrass, intermediate wheatgrass, and susceptible and resistant wheat.

    PubMed

    Merrill, Scott C; Peairs, Frank B; Miller, Hayley R; Randolph, Terri L; Rudolph, Jeff B; Talmich, Emili E

    2008-04-01

    The Russian wheat aphid, Diuraphis noxia (Kurdjumov), is an economically important pest of small grains. Since its introduction into North America in 2003, Russian wheat aphid Biotype 2 has been found to be virulent to all commercially available winter wheat, Triticum aestivum L., cultivars. Our goal was to examine differences in Russian wheat aphid reproduction and development on a variety of plant hosts to gain information about 1) potential alternate host refuges, 2) selective host pressures on Russian wheat aphid genetic variation, and 3) general population dynamics of Russian wheat aphid Biotype 2. We studied host quality of two wheatgrasses (crested wheatgrass, Agropyron cristatum [L.] Gaertn., and intermediate wheatgrass, Agropyron intermedium [Host] Beauvoir) and two types of winter wheat (T. aestivum, one Biotype 2 susceptible wheat, 'Custer' and one biotype 2 resistant wheat, STARS02RWA2414-11). The susceptible wheat had the highest intrinsic rate of increase, greatest longevity and greatest fecundity of the four host studied. Crested wheatgrass and the resistant wheat showed similar growth rates. Intermediate wheatgrass had the lowest intrinsic rate of increase and lowest fecundity of all tested hosts. PMID:18459422

  12. Evidence for stable transformation of wheat by floral dip in Agrobacterium tumefaciens.

    PubMed

    Zale, Janice M; Agarwal, S; Loar, S; Steber, C M

    2009-06-01

    Hexaploid wheat, one of the world's most important staple crops, remains a challenge for genetic transformation. We are developing a floral transformation protocol for wheat that does not require tissue culture. This paper presents three transformants in the hard red germplasm line Crocus that have been characterized thoroughly at the molecular level over three to six generations. Wheat spikes at the early boot stage, i.e. the early, mid or late uninucleate microspore stages, were immersed in an infiltration medium of strain C58C1 harboring pDs(Hyg)35S, or strain AGL1 harboring pBECKSred. pDs(Hyg)35S contains the NPTII and hph selectable markers, and transformants were detected using paromomycin spray at the whole plant level, NPTII ELISAs, or selection on medium with hygromycin. Strain AGL1, harboring pBECKSred, which contains the maize anthocyanin regulators, Lc and C1, and the NPTII gene, was also used to produce a Crocus transformant. T1 and T2 seeds with red embryos were selected; T1 and T2 plants were screened by sequential tests for paromomycin resistance and NPTII ELISAs. The transformants were low copy number and showed Mendelian segregation in the T2. Stable transmission of the transgenes over several generations has been demonstrated using Southern analysis. Gene expression in advanced progeny was shown using Reverse Transcriptase-PCR and ELISA assays for NPTII protein expression. This protocol has the potential to reduce the time and expense required for wheat transformation. PMID:19308413

  13. Effect of 7H(ch) Hordeum chilense chromosome introgressions on the wheat endosperm proteomic profile.

    PubMed

    Collado-Romero, Melania; Alós, Enriqueta; Prieto, Pilar

    2015-04-15

    Hordeum chilense is an excellent genetic resource for wheat breeding due to its potential to improve breadmaking quality and nutritional value and provide resistance to some biotic and abiotic stresses. Hexaploid wheat lines carrying chromosome 7H(ch) introgressions, namely, chromosome additions of the whole chromosome 7H(ch) or the 7H(ch)? or the 7H(ch)? chromosome arms, and chromosome substitutions of the homeologous chromosomes 7A, 7B, or 7D by chromosome 7H(ch) were compared by 2D-PAGE analysis to study the effect of these alien introgressions on the wheat endosperm proteome. The addition of the 7H(ch)? chromosome arm did not alter the profile of most glutenins and gliadins, but showed higher quantities of puroindolines and lower xylanase inhibitors, which might improve also resistance to plant pathogens. On the other hand, (7A)7H(ch) or (7D)7H(ch) substitution lines showed enhanced avenin-like b proteins and triticin levels but reduced puroindolines, which could be desirable to improve dough properties and nutritional value and increase kernel hardness in wheat. PMID:25824108

  14. Potential new sources of wheat curl mite resistance in wheat to prevent the spread of yield-reducing pathogens.

    PubMed

    Richardson, Kelly; Miller, Adam D; Hoffmann, Ary A; Larkin, Philip

    2014-01-01

    The wheat curl mite (WCM), Aceria tosichella Keifer (Trombidiformes: Eriophyidae), is a major pest in cropping regions of the world and is recognised as the primary vector of several yield-reducing pathogens, primarily affecting wheat. Management of WCM is complicated due to several aspects of the mite's biology and ecology; however, commercially viable mite resistant wheat varieties may offer practical long-term management options. Unfortunately, mite populations have adapted to previously identified sources of resistance, highlighting the need for further sources of resistance and the value of stacking different resistances to give greater degrees and longevity of control. In this study we assessed the susceptibility of 42 wheat-derived genotypes to mite population growth using a new experimental method that overcomes methodological limitations of previous studies. Experimental wheat lines included a variety of wheat genotypes, related Triticeae species, wheat-alien chromosome amphiploids, and chromosome addition or substitution lines. From these we identify new promising sources of WCM resistance associated with Thinopyrum intermedium, Th. ponticum and Hordeum marinum chromosomes. More specifically we identify group 1J and 5J chromosomes of the L3 and L5 wheat-Th. intermedium addition lines as new sources of resistance that could be exploited to transfer resistance onto homoeologous wheat chromosomes. This study offers new methods for reliable in situ estimations of mite abundance on cereal plants, and new sources of WCM resistance that may assist management of WCM and associated viruses in wheat. PMID:24705793

  15. NAD-dependent aromatic alcohol dehydrogenase in wheats (Triticum L.) and goatgrasses (Aegilops L.): evolutionary genetics.

    PubMed

    Jaaska, V

    1984-04-01

    Evolutionary electrophoretic variation of a NAD-specific aromatic alcohol dehydrogenase, AADH-E, in wheat and goatgrass species is described and discussed in comparison with a NAD-specific alcohol dehydrogenase (ADH-A) and a NADP-dependent AADH-B studied previously. Cultivated tetraploid emmer wheats (T. turgidum s. l.) and hexaploid bread wheats (T. aestivum s. l.) are all fixed for a heterozygous triplet, E(0.58)/E(0.64). The slowest isoenzyme, E(0.58), is controlled by a homoeoallelic gene on the chromosome arm 6AL of T. aestivum cv. 'Chinese Spring' and is inherent in all diploid wheats, T. monococcum s. Str., T. boeoticum s. l. and T. urartu. The fastest isoenzyme, E(0.64), is presumably controlled by the B- and D-genome homoeoalleles of the bread wheat and is the commonest alloenzyme of diploid goat-grasses, including Ae. speltaides and Ae. tauschii. The tetraploid T. timopheevii s. str. has a particular heterozygous triplet E(0.56)/E(0.71), whereas the hexaploid T. zhukovskyi exhibited polymorphism with electromorphs characteristic of T. timopheevii and T. monococcum. Wild tetraploid wheats, T. dicoccoides and T. araraticum, showed partially homologous intraspecific variation of AADH-E with heterozygous triplets E(0.58)/E(0.64) (the commonest), E(0.58)/E(0.71), E(0.45)/E(0.58), E(0.48)/E(0.58) and E(0.56)/E(0.58) recorded. Polyploid goatgrasses of the D-genome group, excepting Ae. cylindrica, are fixed for the common triplet E(0.58)/E(0.64). Ae. cylindrica and polyploid goatgrasses of the C(u)-genome group, excepting Ae. kotschyi, are homozygous for E(0.64). Ae. kotschyi is exceptional, showing fixed heterozygosity for both AADH-E and ADH-A with unique triplets E(0.56)/E(0.64) and A(0.49)/A(0.56). PMID:24258843

  16. Solid-stemmed wheat does not affect overwintering mortality of the wheat stem sawfly, Cephus cinctus.

    PubMed

    Cárcamo, Héctor A; Beres, Brian L; Herle, Carolyn E; McLean, Hugh; McGinne, Sean

    2011-01-01

    The wheat stem sawfly, Cephus cinctus Norton (Hymenoptera: Cephidae), is a key pest of wheat in the northern Great Plains of North America. Host plant resistance in the form of solid-stemmed wheat cultivars is the main control strategy for C. cinctus. This study investigated the effect of novel and traditional solid wheat hosts on the overwintering mortality and cold-hardiness of C. cinctus. Field conditions from 2003-2005 showed that overwintering mortality in various wheat cultivars averaged 8% and was not related to the type of wheat cultivar. Similarly, supercooling points (-22° C) were not influenced by wheat host type. C. cintus are cold-hardy; up to 80% survive 10 days at -20° C and 10% survive 40 days. Its overwintering microhabitat near the crown area of the plant is well insulated for temperatures above -10° C and remains ~ 20° C above ambient minima. These data suggest that winter mortality is a minor factor in the population dynamics of wheat stem sawfly, and despite clear detrimental effects on larval weight and adult fitness, solid-stemmed cultivars do not reduce the ability of larvae to survive winters. PMID:22235942

  17. Identification and characterization of more than 4 million intervarietal SNPs across the group 7 chromosomes of bread wheat.

    PubMed

    Lai, Kaitao; Lorenc, Micha? T; Lee, Hong Ching; Berkman, Paul J; Bayer, Philipp Emanuel; Visendi, Paul; Ruperao, Pradeep; Fitzgerald, Timothy L; Zander, Manuel; Chan, Chon-Kit Kenneth; Manoli, Sahana; Stiller, Jiri; Batley, Jacqueline; Edwards, David

    2015-01-01

    Despite being a major international crop, our understanding of the wheat genome is relatively poor due to its large size and complexity. To gain a greater understanding of wheat genome diversity, we have identified single nucleotide polymorphisms between 16 Australian bread wheat varieties. Whole-genome shotgun Illumina paired read sequence data were mapped to the draft assemblies of chromosomes 7A, 7B and 7D to identify more than 4 million intervarietal SNPs. SNP density varied between the three genomes, with much greater density observed on the A and B genomes than the D genome. This variation may be a result of substantial gene flow from the tetraploid Triticum turgidum, which possesses A and B genomes, during early co-cultivation of tetraploid and hexaploid wheat. In addition, we examined SNP density variation along the chromosome syntenic builds and identified genes in low-density regions which may have been selected during domestication and breeding. This study highlights the impact of evolution and breeding on the bread wheat genome and provides a substantial resource for trait association and crop improvement. All SNP data are publically available on a generic genome browser GBrowse at www.wheatgenome.info. PMID:25147022

  18. Wheat grass selection

    NSDL National Science Digital Library

    Richard Wang (USDA; ARS)

    2006-09-25

    The wheat grass on the right is not tolerant of high salinity, or high salt conditions. The wheat grass on the left is a hybrid that has a high salt tolerance. It grows well in high salinity environments.

  19. Processing Wheat for Food

    NSDL National Science Digital Library

    Teachers' Domain presents this interactive lesson on wheat processing, including an introduction to the five kinds of wheat grown in the US and the anatomy of wheat. The module then moves through the six steps in wheat processing: cleaning, conditioning, blending, breaking, sieving, and reducing. Each step is animated to help students visualize the process. On the site, visitors will also find a supplemental background essay, discussion questions, and standards alignment from Teachers' Domain.

  20. Genetic diversity of wild emmer wheat in Israel and Turkey

    Microsoft Academic Search

    E. Nevo; A. Beiles

    1989-01-01

    Allozyme variation in the tetraploid wild emmer wheat, Triticum dicoccoides, the progenitor of all cultivated wheats, was studied for the proteins encoded by 42 gene loci in 1815 plants representing 37 populations - 33 from Israel and 4 from Turkey - sampled in 33 localities from 1979 to 1987. The results showed that: (a) 6 loci (14%) were monomorphic in

  1. QUANTITATIVE TRAIT LOCI FOR ALUMINUM RESISTANCE IN WHEAT

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Quantitative trait loci (QTLs) for wheat resistance to aluminum (Al) toxicity were analyzed using simple sequence repeats (SSRs) in a population of 192 F6 recombinant inbred lines (RILs) derived from a cross between an Al-resistant cultivar, Atlas 66 and an Al-sensitive cultivar, Chisholm. Wheat rea...

  2. Wheat: Science and Trade

    Technology Transfer Automated Retrieval System (TEKTRAN)

    This is for a book review of Wheat: science and trade, edited by B.F. Carver. The book provides an indepth review of wheat biology, production, breeding, processing, and trade and is organized in four sections. "Making of a Wheat Plant" reviews domestication, evolution, development, and molecular ...

  3. Wheat Stripe Rust

    Technology Transfer Automated Retrieval System (TEKTRAN)

    This is a chapter on wheat stripe rust in a book entitled “Wheat: Science and Trade”. The chapter provides an overview on various aspects of wheat stripe rust and control, including distribution and epidemiology; origin and historical importance; taxonomy, lifecycle, and host range; genetic variati...

  4. Molecular, physicochemical and rheological characteristics of introgressive Triticale/Triticum monococcum ssp. monococcum lines with wheat 1D/1A chromosome substitution.

    PubMed

    Salmanowicz, Boles?aw P; Langner, Monika; Wi?niewska, Halina; Apolinarska, Barbara; Kwiatek, Micha?; B?aszczyk, Lidia

    2013-01-01

    Three sets of hexaploid introgressive triticale lines, with Triticum monococcum ssp. monococcum (cultivated einkorn wheat) genes and a bread wheat chromosome 1D substituted for chromosome 1A, and one set of secondary triticale lines were evaluated for grain and flour physicochemical and dough rheological characteristics in two generations (F7 and F8). Genomic in situ hybridization (GISH) and fluorescence in situ hybridization (FISH) confirmed the 1D/1A chromosome substitution. The presence or absence of einkorn high-molecular-weight (HMW) glutenin subunits and the wheat Glu-D1d locus encoding the 5 + 10 subunits was assessed by sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE), capillary zone electrophoresis, and allele-specific molecular markers. Significant differences were found among physicochemical properties (with the exception of the Hagberg falling number) of all introgressive Triticale/T. monococcum lines and the secondary triticale lines. The wheat 1D/1A chromosome substitution also affected these properties. The results showed that in all introgressive triticale lines, the protein and gluten content, Zeleny sedimentation value, and water absorption capacity, were increased. The rheological parameters estimated using micro-farinograph, reomixer, and Kieffer dough extensibility systems also showed an appreciable increase in dough-mixing properties, maximum resistance to extension (Rmax), and dough extensibility. Introgressive Triticale/T. monococcum lines with 5 + 10 subunits have particularly favorable rheological parameters. The results obtained in this study suggest that the cultivated einkorn genome Am, in the context of hexaploid secondary triticale lines and with a wheat 1D/1A substitution, has the potential to improve gluten polymer interactions and be a valuable genetic resource for triticale quality improvement. PMID:23896593

  5. Molecular, Physicochemical and Rheological Characteristics of Introgressive Triticale/Triticum monococcum ssp. monococcum Lines with Wheat 1D/1A Chromosome Substitution

    PubMed Central

    Salmanowicz, Boles?aw P.; Langner, Monika; Wi?niewska, Halina; Apolinarska, Barbara; Kwiatek, Micha?; B?aszczyk, Lidia

    2013-01-01

    Three sets of hexaploid introgressive triticale lines, with Triticum monococcum ssp. monococcum (cultivated einkorn wheat) genes and a bread wheat chromosome 1D substituted for chromosome 1A, and one set of secondary triticale lines were evaluated for grain and flour physicochemical and dough rheological characteristics in two generations (F7 and F8). Genomic in situ hybridization (GISH) and fluorescence in situ hybridization (FISH) confirmed the 1D/1A chromosome substitution. The presence or absence of einkorn high-molecular-weight (HMW) glutenin subunits and the wheat Glu-D1d locus encoding the 5 + 10 subunits was assessed by sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE), capillary zone electrophoresis, and allele-specific molecular markers. Significant differences were found among physicochemical properties (with the exception of the Hagberg falling number) of all introgressive Triticale/T. monococcum lines and the secondary triticale lines. The wheat 1D/1A chromosome substitution also affected these properties. The results showed that in all introgressive triticale lines, the protein and gluten content, Zeleny sedimentation value, and water absorption capacity, were increased. The rheological parameters estimated using micro-farinograph, reomixer, and Kieffer dough extensibility systems also showed an appreciable increase in dough-mixing properties, maximum resistance to extension (Rmax), and dough extensibility. Introgressive Triticale/T. monococcum lines with 5 + 10 subunits have particularly favorable rheological parameters. The results obtained in this study suggest that the cultivated einkorn genome Am, in the context of hexaploid secondary triticale lines and with a wheat 1D/1A substitution, has the potential to improve gluten polymer interactions and be a valuable genetic resource for triticale quality improvement. PMID:23896593

  6. Population.

    ERIC Educational Resources Information Center

    King, Pat; Landahl, John

    This pamphlet has been prepared in response to a new problem, a rapidly increasing population, and a new need, population education. It is designed to help teachers provide their students with some basic population concepts with stress placed on the elements of decision making. In the first section of the pamphlet, some of the basic concepts of…

  7. High-Density Genetic Linkage Map Construction and QTL Mapping of Grain Shape and Size in the Wheat Population Yanda1817 × Beinong6

    PubMed Central

    Wu, Qiu-Hong; Chen, Yong-Xing; Zhou, Sheng-Hui; Fu, Lin; Chen, Jiao-Jiao; Xiao, Yao; Zhang, Dong; Ouyang, Shu-Hong; Zhao, Xiao-Jie; Cui, Yu; Zhang, De-Yun; Liang, Yong; Wang, Zhen-Zhong; Xie, Jing-Zhong; Qin, Jin-Xia; Wang, Guo-Xin; Li, De-Lin; Huang, Yin-Lian; Yu, Mei-Hua; Lu, Ping; Wang, Li-Li; Wang, Ling; Wang, Hao; Dang, Chen; Li, Jie; Zhang, Yan; Peng, Hui-Ru; Yuan, Cheng-Guo; You, Ming-Shan; Sun, Qi-Xin; Wang, Ji-Rui; Wang, Li-Xin; Luo, Ming-Cheng; Han, Jun; Liu, Zhi-Yong

    2015-01-01

    High-density genetic linkage maps are necessary for precisely mapping quantitative trait loci (QTLs) controlling grain shape and size in wheat. By applying the Infinium iSelect 9K SNP assay, we have constructed a high-density genetic linkage map with 269 F 8 recombinant inbred lines (RILs) developed between a Chinese cornerstone wheat breeding parental line Yanda1817 and a high-yielding line Beinong6. The map contains 2431 SNPs and 128 SSR & EST-SSR markers in a total coverage of 3213.2 cM with an average interval of 1.26 cM per marker. Eighty-eight QTLs for thousand-grain weight (TGW), grain length (GL), grain width (GW) and grain thickness (GT) were detected in nine ecological environments (Beijing, Shijiazhuang and Kaifeng) during five years between 2010–2014 by inclusive composite interval mapping (ICIM) (LOD?2.5). Among which, 17 QTLs for TGW were mapped on chromosomes 1A, 1B, 2A, 2B, 3A, 3B, 3D, 4A, 4D, 5A, 5B and 6B with phenotypic variations ranging from 2.62% to 12.08%. Four stable QTLs for TGW could be detected in five and seven environments, respectively. Thirty-two QTLs for GL were mapped on chromosomes 1B, 1D, 2A, 2B, 2D, 3B, 3D, 4A, 4B, 4D, 5A, 5B, 6B, 7A and 7B, with phenotypic variations ranging from 2.62% to 44.39%. QGl.cau-2A.2 can be detected in all the environments with the largest phenotypic variations, indicating that it is a major and stable QTL. For GW, 12 QTLs were identified with phenotypic variations range from 3.69% to 12.30%. We found 27 QTLs for GT with phenotypic variations ranged from 2.55% to 36.42%. In particular, QTL QGt.cau-5A.1 with phenotypic variations of 6.82–23.59% was detected in all the nine environments. Moreover, pleiotropic effects were detected for several QTL loci responsible for grain shape and size that could serve as target regions for fine mapping and marker assisted selection in wheat breeding programs. PMID:25675376

  8. Nucleotide diversity maps reveal variation in diversity among wheat genomes and chromosomes

    PubMed Central

    2010-01-01

    Background A genome-wide assessment of nucleotide diversity in a polyploid species must minimize the inclusion of homoeologous sequences into diversity estimates and reliably allocate individual haplotypes into their respective genomes. The same requirements complicate the development and deployment of single nucleotide polymorphism (SNP) markers in polyploid species. We report here a strategy that satisfies these requirements and deploy it in the sequencing of genes in cultivated hexaploid wheat (Triticum aestivum, genomes AABBDD) and wild tetraploid wheat (Triticum turgidum ssp. dicoccoides, genomes AABB) from the putative site of wheat domestication in Turkey. Data are used to assess the distribution of diversity among and within wheat genomes and to develop a panel of SNP markers for polyploid wheat. Results Nucleotide diversity was estimated in 2114 wheat genes and was similar between the A and B genomes and reduced in the D genome. Within a genome, diversity was diminished on some chromosomes. Low diversity was always accompanied by an excess of rare alleles. A total of 5,471 SNPs was discovered in 1791 wheat genes. Totals of 1,271, 1,218, and 2,203 SNPs were discovered in 488, 463, and 641 genes of wheat putative diploid ancestors, T. urartu, Aegilops speltoides, and Ae. tauschii, respectively. A public database containing genome-specific primers, SNPs, and other information was constructed. A total of 987 genes with nucleotide diversity estimated in one or more of the wheat genomes was placed on an Ae. tauschii genetic map, and the map was superimposed on wheat deletion-bin maps. The agreement between the maps was assessed. Conclusions In a young polyploid, exemplified by T. aestivum, ancestral species are the primary source of genetic diversity. Low effective recombination due to self-pollination and a genetic mechanism precluding homoeologous chromosome pairing during polyploid meiosis can lead to the loss of diversity from large chromosomal regions. The net effect of these factors in T. aestivum is large variation in diversity among genomes and chromosomes, which impacts the development of SNP markers and their practical utility. Accumulation of new mutations in older polyploid species, such as wild emmer, results in increased diversity and its more uniform distribution across the genome. PMID:21156062

  9. Inferring the contribution of sexual reproduction, migration and off-season survival to the temporal maintenance of microbial populations: a case study on the wheat fungal pathogen Puccinia striiformis f.sp. tritici.

    PubMed

    Ali, Sajid; Gladieux, Pierre; Rahman, Hidayatur; Saqib, Muhammad S; Fiaz, Muhammad; Ahmad, Habib; Leconte, Marc; Gautier, Angélique; Justesen, Annemarie F; Hovmøller, Mogens S; Enjalbert, Jérôme; de Vallavieille-Pope, Claude

    2014-02-01

    Understanding the mode of temporal maintenance of plant pathogens is an important domain of microbial ecology research. Due to the inconspicuous nature of microbes, their temporal maintenance cannot be studied directly through tracking individuals and their progeny. Here, we suggest a series of population genetic analyses on molecular marker variation in temporally spaced samples to infer about the relative contribution of sexual reproduction, off-season survival and migration to the temporal maintenance of pathogen populations. We used the proposed approach to investigate the temporal maintenance of wheat yellow rust pathogen, Puccinia striiformis f.sp. tritici (PST), in the Himalayan region of Pakistan. Multilocus microsatellite genotyping of PST isolates revealed high genotypic diversity and recombinant population structure across all locations, confirming the existence of sexual reproduction in this region. The genotypes were assigned to four genetic groups, revealing a clear differentiation between zones with and without Berberis spp., the alternate host of PST, with an additional subdivision within the Berberis zone. The lack of any differentiation between samples across two sampling years, and the very infrequent resampling of multilocus genotypes over years at a given location was consistent with limited over-year clonal survival, and a limited genetic drift. The off-season oversummering population in the Berberis zone, likely to be maintained locally, served as a source of migrants contributing to the temporal maintenance in the non-Berberis zone. Our study hence demonstrated the contribution of both sexual recombination and off-season oversummering survival to the temporal maintenance of the pathogen. These new insights into the population biology of PST highlight the general usefulness of the analytical approach proposed. PMID:24354737

  10. How diverse a farmer-managed wheat landrace can be?

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Phenotypic variation in phenological, quantitative and qualitative traits was assessed in geographically-isolated, farmer-managed wheat landrace populations grown under subsistence farming conditions. Several multivariate, genetic diversity and sequential equation modeling procedures were used to bu...

  11. The Structure and Expression of the Wheat Starch Synthase III Gene. Motifs in the Expressed Gene Define the Lineage of the Starch Synthase III Gene Family1

    PubMed Central

    Li, Zhongyi; Mouille, Greg; Kosar-Hashemi, Behjat; Rahman, Sadequr; Clarke, Bryan; Gale, Kevin R.; Appels, Rudi; Morell, Matthew K.

    2000-01-01

    The endosperm of hexaploid wheat (Triticum aestivum [L.]) was shown to contain a high molecular weight starch synthase (SS) analogous to the product of the maize du1 gene, starch synthase III (SSIII; DU1). cDNA and genomic DNA sequences encoding wheat SSIII were isolated and characterized. The wheat SSIII cDNA is 5,346 bp long and contains an open reading frame that encodes a 1,628-amino acid polypeptide. A putative N-terminal transit peptide, a 436-amino acid C-terminal catalytic domain, and a central 470-amino acid SSIII-specific domain containing three regions of repeated amino acid similarity were identified in the wheat gene. A fourth region between the transit peptide and the SSIII-specific domain contains repeat motifs that are variable with respect to motif sequence and repeat number between wheat and maize. In dicots, this N-terminal region does not contain repeat motifs and is truncated. The gene encoding wheat SSIII, designated ss3, consists of 16 exons extending over 10 kb, and is located on wheat chromosome I. Expression of ss3 mRNA in wheat was detected in leaves, pre-anthesis florets, and from very early to middle stage of endosperm development. The entire N-terminal variable repeat region and the majority of the SSIII-specific domain are encoded on a single 2,703-bp exon. A gene encoding a class III SS from the Arabidopsis genome sequencing project shows a strongly conserved exon structure to the wheat ss3 gene, with the exception of the N-terminal region. The evolutionary relationships of the genes encoding monocot and dicot class III SSs are discussed. PMID:10859191

  12. Mitochondrial DNA heteroplasmy in wheat, Aegilops and their nucleus-cytoplasm hybrids.

    PubMed Central

    Hattori, Nobuaki; Kitagawa, Kazuaki; Takumi, Shigeo; Nakamura, Chiharu

    2002-01-01

    A mitochondrial (mt) transcriptional unit, nad3-orf156, was studied in the nucleus-cytoplasm hybrids of wheat with D/D2 plasmons from Aegilops species and their parental lines. A comparative RFLP analysis and sequencing of the random PCR clones revealed the presence of seven sequence types and their polymorphic sites were mapped. All the hybrids possessed the paternal copies besides the maternal copies. More paternal copies were present in the D2 plasmon hybrids, whereas more maternal copies were present in the D plasmon hybrids. Two major copies were present with different stoichiometries in the maternal Aegilops parents. However, only a major D plasmon copy was detected in the hybrids, irrespective of their plasmon types. The hexaploid wheat parent (AABBDD genome) possessed the major D plasmon copy in approximately 5% stoichiometry, while no D plasmon-homologous copies were detected in the tetraploid wheat parent (AABB genome). The results suggest that the observed mtDNA heteroplasmy is due to paternal contribution of mtDNA. The different copy stoichiometry suggests differential amplification of the heteroplasmic copies among the hybrids and the parental lines. All editing sites and their editing frequencies were conserved among the lines, and only the maternal pattern of editing occurred in the hybrids. PMID:11973315

  13. Wheat alleles introgress into selfing wild relatives: empirical estimates from approximate Bayesian computation in Aegilops triuncialis.

    PubMed

    Pajkovic, Mila; Lappe, Sylvain; Barman, Rachel; Parisod, Christian; Neuenschwander, Samuel; Goudet, Jerome; Alvarez, Nadir; Guadagnuolo, Roberto; Felber, François; Arrigo, Nils

    2014-10-01

    Extensive gene flow between wheat (Triticum sp.) and several wild relatives of the genus Aegilops has recently been detected despite notoriously high levels of selfing in these species. Here, we assess and model the spread of wheat alleles into natural populations of the barbed goatgrass (Aegilops triuncialis), a wild wheat relative prevailing in the Mediterranean flora. Our sampling, based on an extensive survey of 31 Ae. triuncialis populations collected along a 60 km × 20 km area in southern Spain (Grazalema Mountain chain, Andalousia, totalling 458 specimens), is completed with 33 wheat cultivars representative of the European domesticated pool. All specimens were genotyped with amplified fragment length polymorphism with the aim of estimating wheat admixture levels in Ae. triuncialis populations. This survey first confirmed extensive hybridization and backcrossing of wheat into the wild species. We then used explicit modelling of populations and approximate Bayesian computation to estimate the selfing rate of Ae. triuncialis along with the magnitude, the tempo and the geographical distance over which wheat alleles introgress into Ae. triuncialis populations. These simulations confirmed that extensive introgression of wheat alleles (2.7 × 10(-4) wheat immigrants for each Ae. triuncialis resident, at each generation) into Ae. triuncialis occurs despite a high selfing rate (Fis ? 1 and selfing rate = 97%). These results are discussed in the light of risks associated with the release of genetically modified wheat cultivars in Mediterranean agrosystems. PMID:25223217

  14. Genomic in situ hybridization reveals both auto- and allopolyploid origins of different North and Central American hexaploid potato (Solanum sect. Petota) species

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Wild potato (Solanum section Petota) species contain diploids (2n = 2x = 24), tetraploids (2n = 4x = 48), hexaploids (2n = 6x = 72), and rare triploids and pentaploids. Determination of the type of polyploidy and the development of the genome concept for section Petota classically was based on the a...

  15. Isolation and sequence analysis of the wheat B genome subtelomeric DNA

    PubMed Central

    Salina, Elena A; Sergeeva, Ekaterina M; Adonina, Irina G; Shcherban, Andrey B; Afonnikov, Dmitry A; Belcram, Harry; Huneau, Cecile; Chalhoub, Boulos

    2009-01-01

    Background Telomeric and subtelomeric regions are essential for genome stability and regular chromosome replication. In this work, we have characterized the wheat BAC (bacterial artificial chromosome) clones containing Spelt1 and Spelt52 sequences, which belong to the subtelomeric repeats of the B/G genomes of wheats and Aegilops species from the section Sitopsis. Results The BAC library from Triticum aestivum cv. Renan was screened using Spelt1 and Spelt52 as probes. Nine positive clones were isolated; of them, clone 2050O8 was localized mainly to the distal parts of wheat chromosomes by in situ hybridization. The distribution of the other clones indicated the presence of different types of repetitive sequences in BACs. Use of different approaches allowed us to prove that seven of the nine isolated clones belonged to the subtelomeric chromosomal regions. Clone 2050O8 was sequenced and its sequence of 119 737 bp was annotated. It is composed of 33% transposable elements (TEs), 8.2% Spelt52 (namely, the subfamily Spelt52.2) and five non-TE-related genes. DNA transposons are predominant, making up 24.6% of the entire BAC clone, whereas retroelements account for 8.4% of the clone length. The full-length CACTA transposon Caspar covers 11 666 bp, encoding a transposase and CTG-2 proteins, and this transposon accounts for 40% of the DNA transposons. The in situ hybridization data for 2050O8 derived subclones in combination with the BLAST search against wheat mapped ESTs (expressed sequence tags) suggest that clone 2050O8 is located in the terminal bin 4BL-10 (0.95-1.0). Additionally, four of the predicted 2050O8 genes showed significant homology to four putative orthologous rice genes in the distal part of rice chromosome 3S and confirm the synteny to wheat 4BL. Conclusion Satellite DNA sequences from the subtelomeric regions of diploid wheat progenitor can be used for selecting the BAC clones from the corresponding regions of hexaploid wheat chromosomes. It has been demonstrated for the first time that Spelt52 sequences were involved in the evolution of terminal regions of common wheat chromosomes. Our research provides new insights into the microcollinearity in the terminal regions of wheat chromosomes 4BL and rice chromosome 3S. PMID:19732459

  16. Characterization of FLOWERING LOCUS T1 (FT1) Gene in Brachypodium and Wheat

    PubMed Central

    Han, Xiuli; Wang, Shuyun; Ni, Fei; Li, Kun; Pearce, Stephen; Wu, Jiajie; Dubcovsky, Jorge; Fu, Daolin

    2014-01-01

    The phase transition from vegetative to reproductive growth is a critical event in the life cycle of flowering plants. FLOWERING LOCUS T (FT) plays a central role in the regulation of this transition by integrating signals from multiple flowering pathways in the leaves and transmitting them to the shoot apical meristem. In this study, we characterized FT homologs in the temperate grasses Brachypodium distachyon and polyploid wheat using transgenic and mutant approaches. Downregulation of FT1 by RNAi was associated with a significant downregulation of the FT-like genes FT2 and FT4 in Brachypodium and FT2 and FT5 in wheat. In a transgenic wheat line carrying a highly-expressed FT1 allele, FT2 and FT3 were upregulated under both long and short days. Overexpression of FT1 caused extremely early flowering during shoot regeneration in both Brachypodium and hexaploid wheat, and resulted in insufficient vegetative tissue to support the production of viable seeds. Downregulation of FT1 transcripts by RNA interference (RNAi) resulted in non-flowering Brachypodium plants and late flowering plants (2–4 weeks delay) in wheat. A similar delay in heading time was observed in tetraploid wheat plants carrying mutations for both FT-A1 and FT-B1. Plants homozygous only for mutations in FT-B1 flowered later than plants homozygous only for mutations in FT-A1, which corresponded with higher transcript levels of FT-B1 relative to FT-A1 in the early stages of development. Taken together, our data indicate that FT1 plays a critical role in the regulation of flowering in Brachypodium and wheat, and that this role is associated with the simultaneous regulation of other FT-like genes. The differential effects of mutations in FT-A1 and FT-B1 on wheat heading time suggest that different allelic combinations of FT1 homoeologs could be used to adjust wheat heading time to improve adaptation to changing environments. PMID:24718312

  17. Studies of yield and quality of grain, yield components, effect of leaf rust, and forage production of mixed varietal populations, and pure stands of varieties in wheat and oats 

    E-print Network

    Da Gama Rose, Renaud Wilfred

    1964-01-01

    . AFFENDIX. page 20 48 54 57 TABLES Table 1 2 3 4 5 6 7 8 9 10 11 12 13 Number of culms of wheat (College Station). Bushels per acre of wheat (College Station) Number of culms of wheat (Beeville). Bushels per acre of wheat (Beeville... at lower temperatures and at later stages of growth. Futrell and Rivers (11) suggested that this type of resistance may partly account for Victoria derivatives not becoming infected with crown rust under cool season temperatures in Texas. Winter...

  18. Wheat Pasture Poisoning. 

    E-print Network

    Crookshank, H. R.; Sims, Frank H.

    1956-01-01

    Tech Field Laboratory near Panhandle by personnel of the Texas Agricultural Experiment Station, Texas Technological College and the U. S. Department of Agriculture on wheat pasture poisoning. The condition known as wheat pasture poisoning occurs primarily... serum of normal cows was compared with the serum of cows affected with wheat pasture poisoning, a decrease in inarganic phos- phate, total and diffusible calcium, magnesium and the albumin-globulin ratio was found in the cases. The total serum protein...

  19. Wheat Evolution: Dough Washing

    NSDL National Science Digital Library

    Biotechnology and Biological Sciences Research Council

    2012-01-01

    In this activity (page 5), learners investigate the evolution of wheat by washing different types of dough with water and comparing the results. The evolution of wheat from wild grasses demonstrates the dramatic effect of both natural and directed evolution on the structure of a crop plant and the chemical makeup of the product harvested from it. These activities illustrate the changes to both the structure and the chemistry of the wheat plant.

  20. De Novo Transcriptome Assembly and Analyses of Gene Expression during Photomorphogenesis in Diploid Wheat Triticum monococcum

    PubMed Central

    Naithani, Sushma; Sullivan, Chris; Preece, Justin; Tiwari, Vijay K.; Elser, Justin; Leonard, Jeffrey M.; Sage, Abigail; Gresham, Cathy; Kerhornou, Arnaud; Bolser, Dan; McCarthy, Fiona; Kersey, Paul; Lazo, Gerard R.; Jaiswal, Pankaj

    2014-01-01

    Background Triticum monococcum (2n) is a close ancestor of T. urartu, the A-genome progenitor of cultivated hexaploid wheat, and is therefore a useful model for the study of components regulating photomorphogenesis in diploid wheat. In order to develop genetic and genomic resources for such a study, we constructed genome-wide transcriptomes of two Triticum monococcum subspecies, the wild winter wheat T. monococcum ssp. aegilopoides (accession G3116) and the domesticated spring wheat T. monococcum ssp. monococcum (accession DV92) by generating de novo assemblies of RNA-Seq data derived from both etiolated and green seedlings. Principal Findings The de novo transcriptome assemblies of DV92 and G3116 represent 120,911 and 117,969 transcripts, respectively. We successfully mapped ?90% of these transcripts from each accession to barley and ?95% of the transcripts to T. urartu genomes. However, only ?77% transcripts mapped to the annotated barley genes and ?85% transcripts mapped to the annotated T. urartu genes. Differential gene expression analyses revealed 22% more light up-regulated and 35% more light down-regulated transcripts in the G3116 transcriptome compared to DV92. The DV92 and G3116 mRNA sequence reads aligned against the reference barley genome led to the identification of ?500,000 single nucleotide polymorphism (SNP) and ?22,000 simple sequence repeat (SSR) sites. Conclusions De novo transcriptome assemblies of two accessions of the diploid wheat T. monococcum provide new empirical transcriptome references for improving Triticeae genome annotations, and insights into transcriptional programming during photomorphogenesis. The SNP and SSR sites identified in our analysis provide additional resources for the development of molecular markers. PMID:24821410

  1. Molecular cytogenetic analysis of wheat - Elymus repens introgression lines with resistance to Fusarium head blight.

    PubMed

    Zeng, J; Cao, W; Hucl, P; Yang, Y; Xue, A; Chi, D; Fedak, G

    2013-01-01

    Elymus repens (L.) Gould (2n = 6x = 42, StStStStHH) is a hexaploid perennial wheatgrass species from the tribe Triticeae, distantly related to bread wheat Triticum aestivum L. (2n = 6x = 42, AABBDD). As a potential source of resistance to Fusarium head blight (FHB), E. repens was crossed to common wheat to transfer resistance genes. The progeny were advanced to homozygosity by single seed descent. A total of eight BC(1)F(9) progeny lines were selected and characterized in this study. The chromosome numbers of these derived lines ranged from 42 to 56, including lines with 44, 52, and 54 chromosomes. All of the lines were cytologically stable in terms of meiotic chromosome behavior. The univalent frequency in the lines varied between 0.34 and 2.36 per cell. Similarly, the multivalent frequency did not exceed 1% in any of the lines. GISH analysis revealed that the number of intact wheat chromosomes in the various lines varied between 40 and 44. Numerous translocated chromosomes were detected in all lines. The translocations involved chromosomal segments from wheat, and the St and H genomes of E. repens. Furthermore, trigenomic translocated chromosomes were detected in some of the lines. The introgression into wheat chromosomes included not only terminal types but also interstitial segments. The Fusarium head blight resistance of the eight lines, following point inoculation, varied from 5.65% infected florets to 11.46% compared with the check cultivars T. aestivum 'Roblin' and T. aestivum 'Crocus' at 100% and 85%, respectively. PMID:23379340

  2. Regulation of VRN-1 Vernalization Genes in Normal and Transgenic Polyploid Wheat1

    PubMed Central

    Loukoianov, Artem; Yan, Liuling; Blechl, Ann; Sanchez, Alexandra; Dubcovsky, Jorge

    2005-01-01

    Vernalization, the requirement of a long exposure to low temperatures to accelerate flowering, is an essential adaptation of plants to cold winters. The vernalization gene VRN-1 plays an important role in this process in diploid (Triticum monococcum) and polyploid wheat (Triticum aestivum). We have recently shown that the diploid wheat VRN-Am1 gene was similar to the Arabidopsis (Arabidopsis thaliana L. Heynh.) APETALA1 meristem identity gene. We also showed that dominant Vrn-Am1 alleles were the result of loss-of-function mutations in regulatory regions recognized by a VRN-1 repressor, likely VRN-2. This model predicts that only the dominant Vrn-1 allele will be transcribed in lines carrying both recessive and dominant alleles. Here, we confirm this prediction in young isogenic lines of hexaploid wheat carrying different dominant Vrn-A1, Vrn-B1, and Vrn-D1 alleles, and also in heterozygous VRN-1 diploid wheat plants. However, a few weeks later, transcripts from the recessive alleles were also detected in both the polyploid and heterozygous diploid spring plants. Transcription of the recessive alleles was preceded by a reduction of the transcript levels of VRN-2. These results suggest that the dominant Vrn-1 allele or a gene regulated by VRN-1 down-regulates the VRN-2 repressor facilitating the transcription of the recessive alleles in unvernalized plants. We also show here that the level of VRN-1 transcripts in early developmental stages is critical for flowering initiation. A reduction of VRN-1 transcript levels by RNA interference delayed apex transition to the reproductive stage, increased the number of leaves, and delayed heading time by 2 to 3 weeks. We hypothesize that the coordinated transcription of dominant and recessive alleles may contribute to an earlier attainment of the VRN-1 transcript level threshold required to trigger flowering initiation in polyploid wheat. PMID:16055679

  3. Response of Spring Wheat Yield and Protein to Row Spacing, Plant Density, and Nitrogen Application in Central Montana

    E-print Network

    Lawrence, Rick L.

    Response of Spring Wheat Yield and Protein to Row Spacing, Plant Density, and Nitrogen Application and agronomic management practices must maximize the efficient use of these resources. Spring wheat development was to investigate effects of plant population, row spacing, and split-application of N on spring wheat yield

  4. Evolution of new disease specificity at a simple resistance locus in a crop-weed complex: reconstitution of the Lr21 gene in wheat.

    PubMed

    Huang, Li; Brooks, Steven; Li, Wanlong; Fellers, John; Nelson, James C; Gill, Bikram

    2009-06-01

    The wheat leaf-rust resistance gene Lr21 was first identified in an Iranian accession of goatgrass, Aegilops tauschii Coss., the D-genome donor of hexaploid bread wheat, and was introgressed into modern wheat cultivars by breeding. To elucidate the origin of the gene, we analyzed sequences of Lr21 and lr21 alleles from 24 wheat cultivars and 25 accessions of Ae. tauschii collected along the Caspian Sea in Iran and Azerbaijan. Three basic nonfunctional lr21 haplotypes, H1, H2, and H3, were identified. Lr21 was found to be a chimera of H1 and H2, which were found only in wheat. We attempted to reconstitute a functional Lr21 allele by crossing the cultivars Fielder (H1) and Wichita (H2). Rust inoculation of 5876 F(2) progeny revealed a single resistant plant that proved to carry the H1H2 haplotype, a result attributed to intragenic recombination. These findings reflect how plants balance the penalty and the necessity of a resistance gene and suggest that plants can reuse "dead" alleles to generate new disease-resistance specificity, leading to a "death-recycle" model of plant-resistance gene evolution at simple loci. We suggest that selection pressure in crop-weed complexes contributes to this process. PMID:19364806

  5. Transcriptome analysis of an mvp mutant reveals important changes in global gene expression and a role for methyl jasmonate in vernalization and flowering in wheat

    PubMed Central

    Diallo, Amadou Oury; Agharbaoui, Zahra; Sarhan, Fathey

    2014-01-01

    The einkorn wheat mutant mvp-1 (maintained vegetative phase 1) has a non-flowering phenotype caused by deletions including, but not limited to, the genes CYS, PHYC, and VRN1. However, the impact of these deletions on global gene expression is still unknown. Transcriptome analysis showed that these deletions caused the upregulation of several pathogenesis-related (PR) and jasmonate-responsive genes. These results suggest that jasmonates may be involved in flowering and vernalization in wheat. To test this hypothesis, jasmonic acid (JA) and methyl jasmonate (MeJA) content in mvp and wild-type plants was measured. The content of JA was comparable in all plants, whereas the content of MeJA was higher by more than 6-fold in mvp plants. The accumulation of MeJA was also observed in vernalization-sensitive hexaploid winter wheat during cold exposure. This accumulation declined rapidly once plants were deacclimated under floral-inductive growth conditions. This suggests that MeJA may have a role in floral transition. To confirm this result, we treated vernalization-insensitive spring wheat with MeJA. The treatment delayed flowering with significant downregulation of both TaVRN1 and TaFT1 genes. These data suggest a role for MeJA in modulating vernalization and flowering time in wheat. PMID:24683181

  6. Family-based mapping of quantitative trait loci in plant breeding populations with resistance to Fusarium head blight in wheat as an illustration

    Microsoft Academic Search

    U. R. Rosyara; J. L. Gonzalez-Hernandez; K. D. Glover; K. R. Gedye; J. M. Stein

    2009-01-01

    Traditional quantitative trait loci (QTL) mapping approaches are typically based on early or advanced generation analysis\\u000a of bi-parental populations. A limitation associated with this methodology is the fact that mapping populations rarely give\\u000a rise to new cultivars. Additionally, markers linked to the QTL of interest are often not immediately available for use in\\u000a breeding and they may not be useful

  7. Identification and mapping of PmG16 , a powdery mildew resistance gene derived from wild emmer wheat

    Microsoft Academic Search

    Roi Ben-David; Weilong Xie; Zvi Peleg; Yehoshua Saranga; Amos Dinoor; Tzion Fahima

    2010-01-01

    The gene-pool of wild emmer wheat, Triticum turgidum ssp. dicoccoides, harbors a rich allelic repertoire for disease resistance. In the current study, we made use of tetraploid wheat mapping\\u000a populations derived from a cross between durum wheat (cv. Langdon) and wild emmer (accession G18-16) to identify and map a\\u000a new powdery mildew resistance gene derived from wild emmer wheat. Initially,

  8. REGISTRATION OF 'TRIBUTE' WHEAT

    Technology Transfer Automated Retrieval System (TEKTRAN)

    ‘Tribute’ (Reg. no. CV-958, PI 632689) is a soft red winter wheat (Triticum aestivum L.) developed and released May 2002 by the Virginia Agricultural Experiment Station. Tribute is broadly adapted and has performed well over most of the soft red winter wheat production regions in the U.S.A. and Can...

  9. Registration of 'Ripper' Wheat

    Technology Transfer Automated Retrieval System (TEKTRAN)

    ‘Ripper’ (Reg. No. CV-1016, PI 644222) hard red winter wheat (Triticum aestivum L.) was developed by the Colorado Agricultural Experiment Station and released in August 2006 through an exclusive marketing agreement with the Colorado Wheat Research Foundation. In addition to researchers at Colorado S...

  10. Registration of 'Antero' Wheat

    Technology Transfer Automated Retrieval System (TEKTRAN)

    ’Antero’ (Reg. No. CV-XXXX, PI 667743) hard white winter wheat (Triticum aestivum L.) was developed by the Colorado Agricultural Experiment Station and released in August 2012 through a marketing agreement with the Colorado Wheat Research Foundation. In addition to researchers at Colorado State Univ...

  11. Agrometeorology and Wheat Production

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Winter wheat phenology varies among shoots on the plant to main stems on plants within a plot to locations across a landscape. Most often phenological measurements have focused on small treatment plots under presumably similar soils and topography. Many models exist to predict wheat phenology for sm...

  12. Registration of 'Snowmass' wheat

    Technology Transfer Automated Retrieval System (TEKTRAN)

    ‘Snowmass’ (Reg. No. CV-1050, PI 658597) hard white winter wheat (Triticum aestivum L.) was developed by the Colorado Agricultural Experiment Station and released in July 2009 through a marketing agreement with the Colorado Wheat Research Foundation. In addition to researchers at Colorado State Uni...

  13. Registration of ‘Yellowstone’ wheat

    Technology Transfer Automated Retrieval System (TEKTRAN)

    'Yellowstone' hard red winter wheat (Triticum aestivum L.) was developed by the Montana Agricultural Experiment Station and released in September 2005. Yellowstone was released for its high yield potential and broad adaptation to Montana winter wheat production environments. Yellowstone was named in...

  14. Infestation of transgenic powdery mildew-resistant wheat by naturally occurring insect herbivores under different environmental conditions.

    PubMed

    Álvarez-Alfageme, Fernando; von Burg, Simone; Romeis, Jörg

    2011-01-01

    A concern associated with the growing of genetically modified (GM) crops is that they could adversely affect non-target organisms. We assessed the impact of several transgenic powdery mildew-resistant spring wheat lines on insect herbivores. The GM lines carried either the Pm3b gene from hexaploid wheat, which confers race-specific resistance to powdery mildew, or the less specific anti-fungal barley seed chitinase and ?-1,3-glucanase. In addition to the non-transformed control lines, several conventional spring wheat varieties and barley and triticale were included for comparison. During two consecutive growing seasons, powdery mildew infection and the abundance of and damage by naturally occurring herbivores were estimated under semi-field conditions in a convertible glasshouse and in the field. Mildew was reduced on the Pm3b-transgenic lines but not on the chitinase/glucanase-expressing lines. Abundance of aphids was negatively correlated with powdery mildew in the convertible glasshouse, with Pm3b wheat plants hosting significantly more aphids than their mildew-susceptible controls. In contrast, aphid densities did not differ between GM plants and their non-transformed controls in the field, probably because of low mildew and aphid pressure at this location. Likewise, the GM wheat lines did not affect the abundance of or damage by the herbivores Oulema melanopus (L.) and Chlorops pumilionis Bjerk. Although a previous study has revealed that some of the GM wheat lines show pleiotropic effects under field conditions, their effect on herbivorous insects appears to be low. PMID:21829479

  15. Effects of combined thiamethoxam and diatomaceous earth on mortality and progeny production of four Pakistani populations of Rhyzopertha dominica (Coleoptera: Bostrychidae) on wheat, rice and maize

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Bioassays were conducted to evaluate the effects of combining thiamethoxam at 0.25, 0.5 and 0.75 mg/kg with the diatomaceous earth (DE) formulation, SilicoSec, at the rate of 100 mg/kg against four diverse populations of the lesser grain borer, Rhyzopertha dominica (F.) (Coleoptera: Bostrychidae) th...

  16. The impact of Ty3-gypsy group LTR retrotransposons Fatima on B-genome specificity of polyploid wheats

    PubMed Central

    2011-01-01

    Background Transposable elements (TEs) are a rapidly evolving fraction of the eukaryotic genomes and the main contributors to genome plasticity and divergence. Recently, occupation of the A- and D-genomes of allopolyploid wheat by specific TE families was demonstrated. Here, we investigated the impact of the well-represented family of gypsy LTR-retrotransposons, Fatima, on B-genome divergence of allopolyploid wheat using the fluorescent in situ hybridisation (FISH) method and phylogenetic analysis. Results FISH analysis of a BAC clone (BAC_2383A24) initially screened with Spelt1 repeats demonstrated its predominant localisation to chromosomes of the B-genome and its putative diploid progenitor Aegilops speltoides in hexaploid (genomic formula, BBAADD) and tetraploid (genomic formula, BBAA) wheats as well as their diploid progenitors. Analysis of the complete BAC_2383A24 nucleotide sequence (113 605 bp) demonstrated that it contains 55.6% TEs, 0.9% subtelomeric tandem repeats (Spelt1), and five genes. LTR retrotransposons are predominant, representing 50.7% of the total nucleotide sequence. Three elements of the gypsy LTR retrotransposon family Fatima make up 47.2% of all the LTR retrotransposons in this BAC. In situ hybridisation of the Fatima_2383A24-3 subclone suggests that individual representatives of the Fatima family contribute to the majority of the B-genome specific FISH pattern for BAC_2383A24. Phylogenetic analysis of various Fatima elements available from databases in combination with the data on their insertion dates demonstrated that the Fatima elements fall into several groups. One of these groups, containing Fatima_2383A24-3, is more specific to the B-genome and proliferated around 0.5-2.5 MYA, prior to allopolyploid wheat formation. Conclusion The B-genome specificity of the gypsy-like Fatima, as determined by FISH, is explained to a great degree by the appearance of a genome-specific element within this family for Ae. speltoides. Moreover, its proliferation mainly occurred in this diploid species before it entered into allopolyploidy. Most likely, this scenario of emergence and proliferation of the genome-specific variants of retroelements, mainly in the diploid species, is characteristic of the evolution of all three genomes of hexaploid wheat. PMID:21635794

  17. Wheat Evolution: Sedimentation Testing

    NSDL National Science Digital Library

    Biotechnology and Biological Sciences Research Council

    2012-01-01

    In this activity (p.8-9 of PDF), learners investigate the evolution of wheat by conducting sedimentation tests on different flours. The evolution of wheat from wild grasses demonstrates the dramatic effect of both natural and directed evolution on the structure of a crop plant and the chemical makeup of the product harvested from it. These activities illustrate the changes to both the structure and the chemistry of the wheat plant. Note: Sedimentation test can also be done using SDS detergent and lactic acid instead of soap and vinegar.

  18. Wheat Evolution: Dough Rising

    NSDL National Science Digital Library

    Biotechnology and Biological Sciences Research Council

    2012-01-01

    In this activity (p.6-7 of PDF), learners investigate the evolution of wheat by creating dough from different flours, observing the samples of dough as they rise, and then baking the dough. The evolution of wheat from wild grasses demonstrates the dramatic effect of both natural and directed evolution on the structure of a crop plant and the chemical makeup of the product harvested from it. These activities illustrate the changes to both the structure and the chemistry of the wheat plant.

  19. A high-density, SNP-based consensus map of tetraploid wheat as a bridge to integrate durum and bread wheat genomics and breeding

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Consensus linkage maps are important tools in crop genomics. We have assembled a high-density tetraploid wheat consensus map by integrating 13 datasets from independent biparental populations involving durum wheat cultivars (Triticum turgidum ssp. durum), cultivated emmer (T. turgidum ssp. dicoccum...

  20. Supplementary Materials for Reckoning wheat yield trends

    E-print Network

    Huybers, Peter

    Supplementary Materials for Reckoning wheat yield trends Marena Lin and Peter Huybers Department decomposition of wheat yields 5 4.1 U.S. county-level wheat yields . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6 4.2 French departmental wheat yields . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6 5

  1. Dissemination of the highly expressed Bx7 glutenin subunit (Glu-B1al allele) in wheat as revealed by novel PCR markers and RP-HPLC.

    PubMed

    Butow, B J; Gale, K R; Ikea, J; Juhász, A; Bedö, Z; Tamás, L; Gianibelli, M C

    2004-11-01

    Increased expression of the high molecular weight glutenin subunit (HMW-GS) Bx7 is associated with improved dough strength of wheat (Triticum aestivum L.) flour. Several cultivars and landraces of widely different genetic backgrounds from around the world have now been found to contain this so-called 'over-expressing' allelic form of the Bx7 subunit encoded by Glu-B1al. Using three methods of identification, SDS-PAGE, RP-HPLC and PCR marker analysis, as well as pedigree information, we have traced the distribution and source of this allele from a Uruguayan landrace, Americano 44D, in the mid-nineteenth century. Results are supported by knowledge of the movement of wheat lines with migrants. All cultivars possessing the Glu-B1al allele can be identified by the following attributes: (1) the elution of the By sub-unit peak before the Dx sub-unit peak by RP-HPLC, (2) high expression levels of Bx7 (>39% Mol% Bx), (3) a 43 bp insertion in the matrix-attachment region (MAR) upstream of the gene promoter relative to Bx7 and an 18 bp nucleotide duplication in the coding region of the gene. Evidence is presented indicating that these 18 and 43 bp sequence insertions are not causal for the high expression levels of Bx7 as they were also found to be present in a small number of hexaploid species, including Chinese Spring, and species expressing Glu-B1ak and Glu-B1a alleles. In addition, these sequence inserts were found in different isolates of the tetraploid wheat, T. turgidum, indicating that these insertion/deletion events occurred prior to hexaploidization. PMID:15340686

  2. Tritrophic Studies of Russian Wheat Aphid, a Parasitoid, and Resistant and Susceptible Wheat over Three Parasitoid Generations

    Microsoft Academic Search

    Abid Farid; J. B Johnson; B Shafii; S. S Quisenberry

    1998-01-01

    Parasitism of Russian wheat aphid,Diuraphis noxia(Mordvilko), byDiaeretiella rapae(McIntosh) was studied over three parasitoid generations on resistant and susceptible wheat,Triticum aestivumL. Rate of increase forD. noxiawas lower when plants were initially infested with 20 aphids than 10 aphids per plant. Plant damage was similar between the two aphid densities (10 and 20 aphids per plant). Rate of population increase forD. noxiawas

  3. No evidence for a role of competitive capabilities of adults in causing habitat segregation of diploid and hexaploid Senecio carniolicus (Asteracaeae)

    Microsoft Academic Search

    Karl Hülber; Andreas Berger; Christian Gilli; Markus Hofbauer; Monika Patek; Gerald M. Schneeweiss

    Hexaploid individuals of Senecio carniolicus (Asteraceae) predominantly occur in dense swards while diploids prevail in open vegetation. We test whether this habitat\\u000a segregation is due to differential responses to competition. Linear regression models were used to relate biomass and maximum\\u000a leaf length of adults to vegetation cover within radii of 20 cm around target individuals. Biomass differed between ploidy\\u000a levels, but

  4. A study of cytological and morphological segregation in "F 1" three-species hybrids derived from hexaploid X diploid crosses of Gossypium

    E-print Network

    Memon, Abdul Rahman M.

    1955-01-01

    and bracteoles of Tetraploids...................... . . . 34 V. Variation in ,fF|_" Tetraploids in Comparison to Triploid hybrids and Hexaploids........... VI. Variation in flower size of uF-j_" Tetraploids ? . 3? VTI. Cytological configurations in Triploids... pollen mother cells examined. 42 PLATE V H Diagrams of the cytological configurations at first meiotic metaphase of F^ Triploid hybrids. Plate VII Cymlojical Confijurahons Observed In Irip lo ids Iff A k X A $? ? ? ?? 32 W # .V W W 0< 3 4...

  5. Quantitative trait loci and epistasis for crown freezing tolerance in the Kanota x Ogle hexaploid oat mapping population.

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Winter hardiness is a complex trait, and poor winter hardiness limits commercial production of winter oat. Crown freeze tolerance is the most important factor conferring winter hardiness, and controlled crown freeze tests correlate well with field winter hardiness. The objective of this study was ...

  6. Resistance and susceptibility of various wheat varieties to Sitobion avenae (Hemiptera: Aphididae) in Iran

    Microsoft Academic Search

    Jabraeil RazmjouShirzad Ramazani; Shirzad Ramazani; Bahram Naseri; Gadir Nouri Ganbalani; Hooshang Rafiee Dastjerdi

    The English grain aphid, Sitobion avenae (Fabricius), is a severe pest of wheat plants in temperate countries. Therefore, we carried out primary screening to assess\\u000a the resistance or susceptibility of 23 commonly grown wheat varieties to this aphid at greenhouse and laboratory conditions\\u000a in Iran. Also, population attributes of this aphid were evaluated on six wheat varieties, namely Saysonz, Arta,

  7. Wheat Diseases Atlas. 

    E-print Network

    McCoy, Norman L.; Berry, Robert W.

    1982-01-01

    CONTENTS INTRODUCTION ........................ . DISSEMINATION OF WHEAT DISEASES ... . ROOT DISEASES ......................... . Root, Crown and Foot Rots ............... . Plant Parasitic Nematodes ................ . Seedling Diseases... . . . . . . . . . . . . . . . . . . . . . . . . . FOLIAGE DISEASES ..................... . 3 3 4 4 4 4 5 Rusts . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5 Leaf Rust . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5 Stem Rust...

  8. Argentina wheat yield model

    NASA Technical Reports Server (NTRS)

    Callis, S. L.; Sakamoto, C.

    1984-01-01

    Five models based on multiple regression were developed to estimate wheat yields for the five wheat growing provinces of Argentina. Meteorological data sets were obtained for each province by averaging data for stations within each province. Predictor variables for the models were derived from monthly total precipitation, average monthly mean temperature, and average monthly maximum temperature. Buenos Aires was the only province for which a trend variable was included because of increasing trend in yield due to technology from 1950 to 1963.

  9. Wheat for Kids! [and] Teacher's Guide.

    ERIC Educational Resources Information Center

    Idaho Wheat Commission, Boise.

    "Wheat for Kids" contains information at the elementary school level about: the structure of the wheat kernel; varieties of wheat and their uses; growing wheat; making wheat dough; the U.S. Department of Agriculture Food Guide Pyramid and nutrition; Idaho's part of the international wheat market; recipes; and word games based on the information…

  10. The wheat transcriptional activator SPA: a seed-specific bZIP protein that recognizes the GCN4-like motif in the bifactorial endosperm box of prolamin genes.

    PubMed Central

    Albani, D; Hammond-Kosack, M C; Smith, C; Conlan, S; Colot, V; Holdsworth, M; Bevan, M W

    1997-01-01

    The conserved bifactorial endosperm box found in the promoter of wheat storage protein genes comprises two different cis elements that are thought to be involved in regulating endosperm-specific gene expression. Endosperm nuclear extracts contain binding activities. One is called ESBF-I, which binds to the endosperm motif (EM), and the other is called ESBF-II, which binds to the GCN4-like motif(GLM). Here, we present a functional analysis of the endosperm box of a low-molecular-weight glutenin gene found on the 1D1 chromosome of hexaploid wheat (LMWG-1D1) in transgenic tobacco plants. Our analysis demonstrates the necessity of the EM and GLM for endosperm-specific gene expression and suggests the presence in tobacco of functional counterparts of wheat ESBF-I and ESBF-II. Furthermore, we describe the isolation and characterization of cDNA clones encoding SPA, a seed-specific basic leucine zipper protein from wheat that can activate transcription from the GLMs of the -326-bp LMWG-1D1 promoter in both maize and tobacco leaf protoplasts. This activation is also partially dependent on the presence of functional EMs, suggesting interactions between SPA with ESBF-I-like activities. PMID:9061949

  11. Construction and evaluation of cDNA libraries for large-scale expressed sequence tag sequencing in wheat (Triticum aestivum L.).

    PubMed

    Zhang, D; Choi, D W; Wanamaker, S; Fenton, R D; Chin, A; Malatrasi, M; Turuspekov, Y; Walia, H; Akhunov, E D; Kianian, P; Otto, C; Simons, K; Deal, K R; Echenique, V; Stamova, B; Ross, K; Butler, G E; Strader, L; Verhey, S D; Johnson, R; Altenbach, S; Kothari, K; Tanaka, C; Shah, M M; Laudencia-Chingcuanco, D; Han, P; Miller, R E; Crossman, C C; Chao, S; Lazo, G R; Klueva, N; Gustafson, J P; Kianian, S F; Dubcovsky, J; Walker-Simmons, M K; Gill, K S; Dvorák, J; Anderson, O D; Sorrells, M E; McGuire, P E; Qualset, C O; Nguyen, H T; Close, T J

    2004-10-01

    A total of 37 original cDNA libraries and 9 derivative libraries enriched for rare sequences were produced from Chinese Spring wheat (Triticum aestivum L.), five other hexaploid wheat genotypes (Cheyenne, Brevor, TAM W101, BH1146, Butte 86), tetraploid durum wheat (T. turgidum L.), diploid wheat (T. monococcum L.), and two other diploid members of the grass tribe Triticeae (Aegilops speltoides Tausch and Secale cereale L.). The emphasis in the choice of plant materials for library construction was reproductive development subjected to environmental factors that ultimately affect grain quality and yield, but roots and other tissues were also included. Partial cDNA expressed sequence tags (ESTs) were examined by various measures to assess the quality of these libraries. All ESTs were processed to remove cloning system sequences and contaminants and then assembled using CAP3. Following these processing steps, this assembly yielded 101,107 sequences derived from 89,043 clones, which defined 16,740 contigs and 33,213 singletons, a total of 49,953 "unigenes." Analysis of the distribution of these unigenes among the libraries led to the conclusion that the enrichment methods were effective in reducing the most abundant unigenes and to the observation that the most diverse libraries were from tissues exposed to environmental stresses including heat, drought, salinity, or low temperature. PMID:15514038

  12. Metabolite Profiling of a Diverse Collection of Wheat Lines Using Ultraperformance Liquid Chromatography Coupled with Time-of-Flight Mass Spectrometry

    PubMed Central

    Wolfe, Pamela; Byrne, Patrick F.; Thompson, Henry J.

    2012-01-01

    Genetic differences among major types of wheat are well characterized; however, little is known about how these distinctions affect the small molecule profile of the wheat seed. Ethanol/water (65% v/v) extracts of seed from 45 wheat lines representing 3 genetically distinct classes, tetraploid durum (Triticum turgidum subspecies durum) (DW) and hexaploid hard and soft bread wheat (T. aestivum subspecies aestivum) (BW) were subjected to ultraperformance liquid chromatography coupled with time-of-flight mass spectrometry (UPLC-TOF-MS). Discriminant analyses distinguished DW from BW with 100% accuracy due to differences in expression of nonpolar and polar ions, with differences attributed to sterol lipids/fatty acids and phospholipids/glycerolipids, respectively. Hard versus soft BW was distinguished with 100% accuracy by polar ions, with differences attributed to heterocyclic amines and polyketides versus phospholipid ions, respectively. This work provides a foundation for identification of metabolite profiles associated with desirable agronomic and human health traits and for assessing how environmental factors impact these characteristics. PMID:22957002

  13. The wheat-Septoria conflict: a new front opening up?

    PubMed

    O'Driscoll, Aoife; Kildea, Steven; Doohan, Fiona; Spink, John; Mullins, Ewen

    2014-09-01

    In the utopic absence of abiotic and/or biotic stressors, attaining the predicted increase (up to 70%) in wheat demand by 2050 in response to global population trends is a challenge. This objective becomes daunting, however, when one factors in the continuous constraint on global wheat production posed by Septoria tritici blotch (STB) disease. This is because, despite resistant loci being identified, a deficit of commercially relevant STB-resistant wheat germplasm remains. The issue is further compounded for growers by the emergence and prevalence of fungicide-resistant/insensitive strains of the causative pathogen Zymoseptoria tritici (formerly known as Mycosphaerella graminicola/Septoria tritici). However, biotechnology-based research is providing new opportunities in this struggle. As the exome response of wheat to STB attack begins to be deciphered, genes intrinsic to resistant and susceptible phenotypes will be identified. Combined with the application of genome-editing techniques and a growing appreciation of the complexity of wheat's and the dynamism of Z. tritici's genome, the generation of resulting STB-resistant wheat varieties will counter the prevalent threat of STB disease in wheat-production systems. PMID:24957882

  14. A high-density microsatellite consensus map for bread wheat ( Triticum aestivum L.)

    Microsoft Academic Search

    Daryl J. Somers; Peter Isaac; Keith Edwards

    2004-01-01

    A microsatellite consensus map was constructed by joining four independent genetic maps of bread wheat. Three of the maps were F1-derived, doubled-haploid line populations and the fourth population was ‘Synthetic’ × ‘Opata’, an F6-derived, recombinant-inbred line population. Microsatellite markers from different research groups including the Wheat Microsatellite Consortium, GWM, GDM, CFA, CFD, and BARC were used in the mapping. A

  15. Distribution and diversity of Russian wheat aphid (Hemiptera: Aphididae) biotypes in South Africa and Lesotho.

    PubMed

    Jankielsohn, Astrid

    2011-10-01

    Russian wheat aphid, Diuraphis noxia (Kurdjumov) (Hemiptera: Aphididae) was recorded for the first time in South Africa in 1978. In 2005, a second biotype, RWASA2, emerged, and here we report on the emergence of yet another biotype, found for the first time in 2009. The discovery of new Russian wheat aphid biotypes is a significant challenge to the wheat, Triticum aestivum L., industry in South Africa. Russian wheat aphid resistance in wheat, that offered wheat producers a long-term solution to Russian wheat aphid control, may no longer be effective in areas where the new biotypes occur. It is therefore critical to determine the diversity and extent of distribution of biotypes in South Africa to successfully deploy Russian wheat aphid resistance in wheat. Screening of 96 Russian wheat aphid clones resulted in identification of three Russian wheat aphid biotypes. Infestations of RWASA1 caused susceptible damage symptoms only in wheat entries containing the Dn3 gene. Infestations of RWASA2 caused susceptible damage symptoms in wheat entries containing Dn1, Dn2, Dn3, and Dn9 resistant genes. Based on the damage-rating scores for the seven resistance sources, a new biotype, which caused damage rating scores different from those for RWASA1 and RWASA2, was evident among the Russian wheat aphid populations tested. This new biotype is virulent to the same resistance sources as RWASA2 (Dn1, Dn2, Dn3, and Dn9), but it also has added virulence to Dn4, whereas RWASA2 is avirulent to this resistance source. PMID:22066205

  16. Insects which challenge global wheat production: Russian wheat aphid

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The book chapter on Russian wheat aphid, (Diuraphis noxia (Mord.)), is one of several that addresses significant pests in the book entitled, Wheat Science and Trade. The chapter gives a detailed account of the history of the Russian wheat aphid as global pest, and its biology, ecology and managemen...

  17. New Uses for Wheat and Modified Wheat Products

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Hard wheat from the Great Plains historically has been used as a source of flour for the production of leavened bakery products. However, potentially applications of wheat in both new markets and new products has necessitated the need to develop wheats with novel processing attributes. The most lo...

  18. Flowering time control in European winter wheat

    PubMed Central

    Langer, Simon M.; Longin, C. Friedrich H.; Würschum, Tobias

    2014-01-01

    Flowering time is an important trait in wheat breeding as it affects adaptation and yield potential. The aim of this study was to investigate the genetic architecture of flowering time in European winter bread wheat cultivars. To this end a population of 410 winter wheat varieties was evaluated in multi-location field trials and genotyped by a genotyping-by-sequencing approach and candidate gene markers. Our analyses revealed that the photoperiod regulator Ppd-D1 is the major factor affecting flowering time in this germplasm set, explaining 58% of the genotypic variance. Copy number variation at the Ppd-B1 locus was present but explains only 3.2% and thus a comparably small proportion of genotypic variance. By contrast, the plant height loci Rht-B1 and Rht-D1 had no effect on flowering time. The genome-wide scan identified six QTL which each explain only a small proportion of genotypic variance and in addition we identified a number of epistatic QTL, also with small effects. Taken together, our results show that flowering time in European winter bread wheat cultivars is mainly controlled by Ppd-D1 while the fine tuning to local climatic conditions is achieved through Ppd-B1 copy number variation and a larger number of QTL with small effects. PMID:25346745

  19. Mapping Quantitative Trait Loci for Long Coleoptile in Chinese Wheat Landrace Wangshuibai

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Wheat (Triticum aestivum L.) cultivars with long coleoptiles can be sown deeply for better seedling establishment in drought environments. A population of 139 recombinant inbred lines (RILs) from a cross between a long-coleoptile Chinese landrace, Wangshuibai, and short coleoptile U.S. wheat cultiva...

  20. Spatially Located Platform and Aerial Photography for Documentation of Grazing Impacts on Wheat

    Microsoft Academic Search

    Mounir Louhaichi; Michael M. Borman; Douglas E. Johnson

    2001-01-01

    Goose populations that winter in Oregon's Lower Willamette Valley have increased from 25 000 to more than 250 000 birds in the last 25 years, resulting in heavy grazing of wheat and other crops. To map and document the extent and intensity of goose impacts on wheat fields, we combined rectified aerial photography with both globally positioned ground observations and

  1. Uniquely identifying wheat plant structures

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Uniquely naming wheat (Triticum aestivum L. em Thell) plant parts is useful for communicating plant development research and the effects of environmental stresses on normal wheat development. Over the past 30+ years, several naming systems have been proposed for wheat shoot, leaf, spike, spikelet, ...

  2. Whole Wheat Strawberry Muffins Ingredients

    E-print Network

    Liskiewicz, Maciej

    Whole Wheat Strawberry Muffins Ingredients: Non stick cooking spray 1 cup strawberries, chopped 2 wheat flour 1/2 cup brown sugar, packed 1 1/2 teaspoons baking soda Directions 1. Heat oven to 400º bowl mix together whole wheat flour, brown sugar and baking soda. Mix well. 5. Add strawberry mixture

  3. Intraspecific sequence comparisons reveal similar rates of non-collinear gene insertion in the B and D genomes of bread wheat

    PubMed Central

    2012-01-01

    Background Polyploidization is considered one of the main mechanisms of plant genome evolution. The presence of multiple copies of the same gene reduces selection pressure and permits sub-functionalization and neo-functionalization leading to plant diversification, adaptation and speciation. In bread wheat, polyploidization and the prevalence of transposable elements resulted in massive gene duplication and movement. As a result, the number of genes which are non-collinear to genomes of related species seems markedly increased in wheat. Results We used new-generation sequencing (NGS) to generate sequence of a Mb-sized region from wheat chromosome arm 3DS. Sequence assembly of 24 BAC clones resulted in two scaffolds of 1,264,820 and 333,768 bases. The sequence was annotated and compared to the homoeologous region on wheat chromosome 3B and orthologous loci of Brachypodium distachyon and rice. Among 39 coding sequences in the 3DS scaffolds, 32 have a homoeolog on chromosome 3B. In contrast, only fifteen and fourteen orthologs were identified in the corresponding regions in rice and Brachypodium, respectively. Interestingly, five pseudogenes were identified among the non-collinear coding sequences at the 3B locus, while none was found at the 3DS locus. Conclusion Direct comparison of two Mb-sized regions of the B and D genomes of bread wheat revealed similar rates of non-collinear gene insertion in both genomes with a majority of gene duplications occurring before their divergence. Relatively low proportion of pseudogenes was identified among non-collinear coding sequences. Our data suggest that the pseudogenes did not originate from insertion of non-functional copies, but were formed later during the evolution of hexaploid wheat. Some evidence was found for gene erosion along the B genome locus. PMID:22935214

  4. Thermoformed wheat gluten biopolymers.

    PubMed

    Pallos, Ferenc M; Robertson, George H; Pavlath, Attila E; Orts, William J

    2006-01-25

    The quantity of available wheat gluten exceeds the current food use markets. Thermoforming is an alternative technical means for transforming wheat gluten. Thermoforming was applied here to wheat gluten under chemically reductive conditions to form pliable, translucent sheets. A wide variety of conditions, i.e., temperature, reducing agents, plasticizers and additives were tested to obtain a range of elastic properties in the thermoformed sheets. These properties were compared to those of commercially available polymers, such as polypropylene. Elasticity of the gluten formulations were indexed by Young's modulus and were in the range measured for commercial products when tested in the 30-70% relative humidity range. Removal of the gliadin subfraction of gluten yielded polymers with higher Young's modulus since this component acts as a polymer-chain terminator. At relative humidity less than 30% all whole gluten-based sheets were brittle, while above 70% they were highly elastic. PMID:16417290

  5. Biolistics Transformation of Wheat

    NASA Astrophysics Data System (ADS)

    Sparks, Caroline A.; Jones, Huw D.

    We present a complete, step-by-step guide to the production of transformed wheat plants using a particle bombardment device to deliver plasmid DNA into immature embryos and the regeneration of transgenic plants via somatic embryogenesis. Currently, this is the most commonly used method for transforming wheat and it offers some advantages. However, it will be interesting to see whether this position is challenged as facile methods are developed for delivering DNA by Agrobacterium tumefaciens or by the production of transformants via a germ-line process (see other chapters in this book).

  6. Registration of 'Juniper' Wheat

    Technology Transfer Automated Retrieval System (TEKTRAN)

    ‘Juniper’ (PI 639951) is a hard red winter wheat (Triticum aestivum L.) developed by the Idaho Agricultural Experimental Station and released in February 2006. Juniper, named for the town of Juniper, Idaho, was released for its superior yield and quality compared with previous full stature hard red...

  7. Registration of ‘Jamestown’ Wheat

    Technology Transfer Automated Retrieval System (TEKTRAN)

    ‘Jamestown’ (Reg. No. CV-1041, PI 653731) soft red winter wheat (Triticum aestivum L.) was developed and released by the Virginia Agricultural Experiment Station in March 2007. Jamestown was derived from the cross ‘Roane’/Pioneer Brand ‘2691’ and was tested under the experimental number VA02W-370. J...

  8. Registration of ‘Shirley’ Wheat

    Technology Transfer Automated Retrieval System (TEKTRAN)

    ‘Shirley’ (Reg. No. CV-1039, PI 656753) soft red winter (SRW) wheat (Triticum aestivum L.), developed and tested as VA03W-409 by the Virginia Agricultural Experiment Station, was released in March 2008. Shirley was derived from the three-way cross VA94-52-25/‘Coker 9835’//VA96-54-234. Shirley is wid...

  9. Wheat Production in Texas. 

    E-print Network

    Atkins, I. M.; Porter, K. B.; Merkle, O. G.; Lahr, K. A.; Gilmore, E. C.

    1970-01-01

    half of the Tesr; acreage. The acreages of varieties and percent- age of the State total, by research testing area.;. are given in Table 7. Tascosa now occupie: TABLE 7. ACREAGES AND PERCENT OF TOTAL FOR WHEAT VARIETIES GROWN IN TEXAS IN 1968' I...

  10. Registration of Colter wheat

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Colter’ (Reg. No. CV-1099, PI 670156) hard red winter wheat (Triticum aestivum L.) was developed and released by the Montana Agricultural Experiment Stations in September 2013. Colter was derived from the cross MT9982*2/BZ9W96-895. MT9982 is a sib selection of 'Yellowstone', and BZ9W96-895 is an unr...

  11. Registration of ‘Judee’ wheat

    Technology Transfer Automated Retrieval System (TEKTRAN)

    ‘Judee’ (Reg. No. CV-1084, PI 665227) hard red winter (HRW) wheat (Triticum aestivum L.) was developed and released by the Montana Agricultural Experiment Station in September 2011. Judee has the pedigree ‘Vanguard’/‘Norstar’//‘Judith’ dwarf selection/3/‘NuHorizon’. Judee was developed using a modif...

  12. Registration of ‘Alice’ Wheat

    Technology Transfer Automated Retrieval System (TEKTRAN)

    ‘Alice’ (Reg. No. CV-1023, PI 644223) hard white winter wheat (Triticum aestivum L.) was developed by the South Dakota Agricultural Experiment Station and released in 2006 to seed producers by the developing institution and the Nebraska Agricultural Experiment Station. Alice was selected from the cr...

  13. Registration of ‘Jamestown’ Wheat

    Technology Transfer Automated Retrieval System (TEKTRAN)

    ‘Jamestown’ (Reg. No. CV-, PI 653731) soft red winter wheat (Triticum aestivum L.) was developed and released by the Virginia Agricultural Experiment Station in March 2007. Jamestown was derived from the cross ‘Roane’ (PI 612958)/Pioneer Brand ‘2691’ (PI 590941 PVPO) and was tested under the experim...

  14. Registration of 'Chesapeake' Wheat

    Technology Transfer Automated Retrieval System (TEKTRAN)

    ‘Chesapeake’ (Reg. No. CV-1011, PI 643935) is a soft red winter wheat (Triticum aestivum L.) that was jointly developed and released by the Maryland Agricultural Experiment Station, Department of Plant Science and Landscape Architecture, and the Virginia Agricultural Experiment Station in 2005. Ches...

  15. Registration of ‘Shirley’ Wheat

    Technology Transfer Automated Retrieval System (TEKTRAN)

    ‘Shirley’ (Reg. No. CV-, PI) soft red winter (SRW) wheat (Triticum aestivum L.) was developed by the Virginia Agricultural Experiment Station and released in March 2008. Shirley was derived from the three-way cross VA94-52-25 / ‘Coker 9835’ (PI 548846 PVPO) // VA96-54-234. Shirley is widely adapted ...

  16. Registration of Camelot Wheat

    Technology Transfer Automated Retrieval System (TEKTRAN)

    'Camelot ' (PI 653832) hard red winter wheat (Triticum aestivum L.) was developed cooperatively by the Nebraska Agricultural Experiment Station and the USDA-ARS and released in 2008. In addition to researchers at the releasing institutions, USDA-ARS researchers at Manhattan, KS, and St. Paul, MN, ...

  17. Registration of ‘Darrell’ Wheat

    Technology Transfer Automated Retrieval System (TEKTRAN)

    ‘Darrell’ (Reg. No. CV-1024, PI 644224) hard red winter wheat (Triticum aestivum L.) was developed by the South Dakota State University–Agricultural Experiment Station and released in 2006 to seed producers by the South Dakota State University–Agricultural Experiment Station and the University of Ne...

  18. Registration of ‘MDM’ wheat

    Technology Transfer Automated Retrieval System (TEKTRAN)

    ‘MDM’ (J980628, WA007936) hard white winter wheat (HWW) (Triticum aestivum L.) (Reg. No. CV-XXX, PI 634716) was released in 2005 by the Agricultural Research Center of Washington State University (WSU) in cooperation with the USDA-ARS. MDM is a semi dwarf cultivar adapted to the low- to intermediat...

  19. REGISTRATION OF 'BAUERMEISTER' WHEAT

    Technology Transfer Automated Retrieval System (TEKTRAN)

    'Bauermeister' (J981107, WA007939) hard red winter wheat (HRW)(Triticum aestivum L.) (Reg. No. CV-XXX, PI 634717) was released in 2005 by the Agricultural Research Center of Washington State University (WSU) in cooperation with the USDA-ARS. Bauermeister is a semidwarf cultivar adapted to the low- ...

  20. REGISTRATION OF GOODSTREAK WHEAT

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Goodstreak¿ (Reg. No. Cv- , PI ) is a hard red winter wheat (Triticum aestivum L.) cultivar developed cooperatively by the Nebraska Agricultural Experiment Station and the USDA-ARS and released in 2000 by the developing institutions and the Wyoming Agricultural Experiment Station. Goodstreak was re...

  1. Registration of ‘Bearpaw’ wheat

    Technology Transfer Automated Retrieval System (TEKTRAN)

    ‘Bearpaw’ (Reg. No. CV-1083, PI 665228) hard red winter (HRW) wheat (Triticum aestivum L.) was developed and released by the Montana Agricultural Experiment Station in September 2011. Bearpaw is of unknown pedigree, derived from a composite of five crosses made to the same F1 male sterile parent in ...

  2. Registration of 'Guymon' wheat

    Technology Transfer Automated Retrieval System (TEKTRAN)

    'Guymon' (Reg. No. CV-_______, PI 643133) is a hard white (HW) winter wheat (Triticum aestivum L.) cultivar developed and released cooperatively by the Oklahoma Agric. Exp. Stn. (AES) and the USDA-ARS in 2005. It is recommended for grain-only and dual-purpose production systems in an area of the so...

  3. REGISTRATION OF 'HATCHER' WHEAT.

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Hatcher (Reg. no. CV-971, PI 638512) hard red winter wheat (Triticum aestivum L.) was developed by the Colorado Agricultural Experiment Station and released to seed producers in August 2004. Hatcher was released based on its resistance to the original North American biotype, designated as Biotype 1...

  4. REGISTRATION OF 'DELIVER' WHEAT

    Technology Transfer Automated Retrieval System (TEKTRAN)

    ‘Deliver’ (Reg. No. CV-_______, PI 639232) hard red winter wheat (Triticum aestivum L.) was released to certified seed growers with permission of the Oklahoma Agricultural Experiment Station (AES) and the USDA-ARS in 2004. Deliver, an awnletted cultivar, was named for its unique and competitive abil...

  5. Registration of "Merl" Wheat.

    Technology Transfer Automated Retrieval System (TEKTRAN)

    ‘Merl’ (Reg. No. CV- , PI 658598) soft red winter (SRW) wheat (Triticum aestivum L.)developed and tested as VA03W-412 by the Virginia Agricultural Experiment Station was released in March 2009. Merl was derived from the three-way cross ‘Roane’ / Pioneer Brand ‘2643’ // ‘38158’ (PI 619052). Merl is a...

  6. Registration of 'Otto' Wheat

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Resistance to strawbreaker foot rot (caused by Oculimacula yallundae Crous & W. Gams and O. acuformis Crous & W. Gams) and to stripe rust (caused by Puccinia striiformis Westend. f. sp. tritici Eriks.) are important traits for winter wheat cultivars produced in the Pacifi Northwest region of the Uni...

  7. Wheat Breeding Activity

    NSDL National Science Digital Library

    This interactive activity goes through the basic process used in a wheat breeding program. Crossing, genetic variation, selection and elements of DNA technology are discussed within this activity. The material is aimed towards high school or introductory life science undergraduate students.

  8. Registration of ‘5205’ Wheat

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The soft red winter (SRW) wheat (Triticum aestivum L.) cultivar ‘5205’ (Reg. No. CV-, PI) was developed by the Virginia Agricultural Experiment Station and released in March 2008. Cultivar 5205 was derived from the three-way cross Pioneer Brand ‘2684’ (PI 566923 PVPO) / VA93-54-185 // ’Pocahontas’ ...

  9. Registration of ‘Brick’ Wheat

    Microsoft Academic Search

    K. D. Glover; J. C. Rudd; R. N. Devkota; R. G. Hall; Y. Jin; L. E. Osborne; J. A. Ingemansen; J. R. Rickertsen; D. D. Baltensperger; G. A. Hareland

    2010-01-01

    Alice' (Reg. No. CV-1023, PI 644223) hard white winter wheat (Triticum aestivum L.) was developed by the South Dakota Agricultural Experiment Station and released in 2006 to seed producers by the developing institution and the Nebraska Agricultural Experiment Station. Alice was selected from the cross 'Abilene' (PI 511307)\\/'Karl' (PI 527480) made in 1992 at Brookings, SD. Alice was selected as

  10. REGISTRATION OF ‘CHOPTANK’ WHEAT

    Technology Transfer Automated Retrieval System (TEKTRAN)

    ‘Choptank’ (Reg. no. CV-976, PI 639724) is a soft red winter wheat (triticum aestivum L.) that was jointly developed and released by the Maryland Agricultural Experiment Station, Department of Natural Resource Sciences and Landscape Architecture, and the Virginia Agricultural Experiment Station in 2...

  11. Registration of ‘3434’ Wheat

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Soft red winter (SRW) wheat (Triticum aestivum L.) cultivar 3434 (Reg. No. CV-1040, PI 656754) developed and tested as VA03W-434 by the Virginia Agricultural Experiment Station was released in March 2008. Cultivar 3434 was derived from the three-way cross ‘Roane’/‘Coker 9835’//VA96W-270. Cultivar 34...

  12. REGISTRATION OF 'GLENN' WHEAT.

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Glenn (Reg. no. CV- , PI 639273), is a hard red spring wheat (Triticum aestivum L.) developed at North Dakota State university and released by the North Dakota Agricultural Experiment Station in July 2005. Glenn was released because it combines a very high level of resistance to Fusarium head bli...

  13. REGISTRATION OF 'JERRY' WHEAT

    Technology Transfer Automated Retrieval System (TEKTRAN)

    'Jerry' is a hard red winter wheat (Triticum aestivum L.) cultivar developed by the North Dakota Agricultural Experiment Station in cooperation with the USDA-ARS and released in 2001. Jerry was tested as ND9257 and is an F3-derived line from the cross 'Roughrider'/ND7571//'Arapahoe' made in 1987 by...

  14. Registration of ‘Decade’ wheat

    Technology Transfer Automated Retrieval System (TEKTRAN)

    'Decade’ (Reg. No. CV-1058, PI 660291) hard red winter (HRW) wheat (Triticum aestivum L.) was developed and released jointly by the Montana and North Dakota Agricultural Experiment Stations in 2010. The name “Decade” denotes the extended time period (1997–2010) during which the Montana State Univers...

  15. Registration of ‘Colter’ wheat

    Technology Transfer Automated Retrieval System (TEKTRAN)

    ‘Colter’ (Reg. No. CV-1099, PI 670156) hard red winter wheat (Triticum aestivum L.) was developed and released by the Montana Agricultural Experiment Stations in September 2013. Colter was derived from the cross MT9982*2/BZ9W96-895. MT9982 is a sib selection of ‘Yellowstone’, and BZ9W96-895 is an un...

  16. Tetraploid Wheat Landraces in the Mediterranean Basin: Taxonomy, Evolution and Genetic Diversity

    PubMed Central

    Oliveira, Hugo R.; Campana, Michael G.; Jones, Huw; Hunt, Harriet V.; Leigh, Fiona; Redhouse, David I.; Lister, Diane L.; Jones, Martin K.

    2012-01-01

    The geographic distribution of genetic diversity and the population structure of tetraploid wheat landraces in the Mediterranean basin has received relatively little attention. This is complicated by the lack of consensus concerning the taxonomy of tetraploid wheats and by unresolved questions regarding the domestication and spread of naked wheats. These knowledge gaps hinder crop diversity conservation efforts and plant breeding programmes. We investigated genetic diversity and population structure in tetraploid wheats (wild emmer, emmer, rivet and durum) using nuclear and chloroplast simple sequence repeats, functional variations and insertion site-based polymorphisms. Emmer and wild emmer constitute a genetically distinct population from durum and rivet, the latter seeming to share a common gene pool. Our population structure and genetic diversity data suggest a dynamic history of introduction and extinction of genotypes in the Mediterranean fields. PMID:22615891

  17. New insights into the organization, recombination, expression and functional mechanism of low molecular weight glutenin subunit genes in bread wheat.

    PubMed

    Dong, Lingli; Zhang, Xiaofei; Liu, Dongcheng; Fan, Huajie; Sun, Jiazhu; Zhang, Zhongjuan; Qin, Huanju; Li, Bin; Hao, Shanting; Li, Zhensheng; Wang, Daowen; Zhang, Aimin; Ling, Hong-Qing

    2010-01-01

    The bread-making quality of wheat is strongly influenced by multiple low molecular weight glutenin subunit (LMW-GS) proteins expressed in the seeds. However, the organization, recombination and expression of LMW-GS genes and their functional mechanism in bread-making are not well understood. Here we report a systematic molecular analysis of LMW-GS genes located at the orthologous Glu-3 loci (Glu-A3, B3 and D3) of bread wheat using complementary approaches (genome wide characterization of gene members, expression profiling, proteomic analysis). Fourteen unique LMW-GS genes were identified for Xiaoyan 54 (with superior bread-making quality). Molecular mapping and recombination analyses revealed that the three Glu-3 loci of Xiaoyan 54 harbored dissimilar numbers of LMW-GS genes and covered different genetic distances. The number of expressed LMW-GS in the seeds was higher in Xiaoyan 54 than in Jing 411 (with relatively poor bread-making quality). This correlated with the finding of higher numbers of active LMW-GS genes at the A3 and D3 loci in Xiaoyan 54. Association analysis using recombinant inbred lines suggested that positive interactions, conferred by genetic combinations of the Glu-3 locus alleles with more numerous active LMW-GS genes, were generally important for the recombinant progenies to attain high Zeleny sedimentation value (ZSV), an important indicator of bread-making quality. A higher number of active LMW-GS genes tended to lead to a more elevated ZSV, although this tendency was influenced by genetic background. This work provides substantial new insights into the genomic organization and expression of LMW-GS genes, and molecular genetic evidence suggesting that these genes contribute quantitatively to bread-making quality in hexaploid wheat. Our analysis also indicates that selection for high numbers of active LMW-GS genes can be used for improvement of bread-making quality in wheat breeding. PMID:20975830

  18. Association between allelic variation at the Phytoene synthase 1 gene and yellow pigment content in the wheat grain.

    PubMed

    Zhang, W; Dubcovsky, J

    2008-03-01

    A better understanding of the genetic factors controlling grain yellow pigment content (GYPC) is important for both pasta (high GYPC) and bread wheat (low GYPC) quality improvement. Quantitative trait loci (QTL) for GYPC have been mapped repeatedly on the distal regions of chromosome arms 7AL and 7BL in wheat, and the Phytoene synthase 1 (PSY-1) gene located in this region has been proposed as a candidate gene. We show here that PSY-E1, the tall wheatgrass orthologue, is completely linked to differences in GYPC, and that selection for white endosperm mutants in recombinant lines carrying this gene resulted in the identification of a mutation in a conserved amino acid of PSY-E1. These results, together with the association between GYPC and allelic differences in PSY-1 in hexaploid wheat, suggest that this gene plays an important role in the determination of GYPC. However, a second white endosperm mutant previously mapped to chromosome arm 7EL showed no mutations in PSY-E1 suggesting the existence of additional gene(s) affecting GYPC in this chromosome region. This hypothesis was further supported by the mapping of QTL for GYPC on 7AL proximal to PSY-1 in a cross between pasta wheat varieties UC1113 and Kofa. Interestingly, the Kofa PSY-B1 allele showed unusually high levels of polymorphisms as a result of a conversion event involving the PSY-A1 allele. In summary, our results support the hypothesis that allelic differences in PSY-1 and at least one additional gene in the distal region of the long arm of homoeologous group 7L are associated with differences in GYPC. PMID:18193186

  19. Cancer mortality in four northern wheat-producing states.

    PubMed Central

    Schreinemachers, D M

    2000-01-01

    Chlorophenoxy herbicides are used both in cereal grain agriculture and in nonagricultural settings such as right-of-ways, lawns, and parks. Minnesota, North Dakota, South Dakota, and Montana grow most of the spring and durum wheat produced in the United States. More than 90% of spring and durum wheat is treated with chlorophenoxy herbicides, in contrast to treatment of approximately 30% of winter wheat. In this ecologic study I used wheat acreage as a surrogate for exposure to chlorophenoxy herbicides. I investigated the association of chlorophenoxy herbicides with cancer mortality during 1980-1989 for selected counties based on level of agriculture ([greater and equal to] 20%) and rural population ([greater and equal to] 50%). Age-standardized cancer mortality rates were determined for grouped counties based on tertiles of wheat acreage per county or for individual counties for frequently occurring cancers. The cancer sites that showed positive trends of increasing cancer mortality with increasing wheat acreage were esophagus, stomach, rectum, pancreas, larynx, prostate, kidney and ureter, brain, thyroid, bone, and all cancers (men) and oral cavity and tongue, esophagus, stomach, liver and gall bladder and bile ducts, pancreas, cervix, ovary, bladder, and other urinary organs, and all cancers (women). Rare cancers in men and women and cancers in boys and girls were studied by comparing counties above and below the median of wheat acreage per county. There was increased mortality for cancer of the nose and eye in both men and women, brain and leukemia in both boys and girls, and all cancers in boys. These results suggest an association between cancer mortality and wheat acreage in counties of these four states. PMID:11017893

  20. Structural changes during early embryogenesis in wheat pollen

    Microsoft Academic Search

    F. J. Bonet; A. Olmedilla

    2000-01-01

    Summary We have made a detailed cytological examination of the development of wheat embryoids, monitoring their initial divisions from two to ten cells by both light and electron microscopy. According to our observations the first embryogenic division is symmetrical. After the androgenesis induction treatment, there is a decrease in ribosome population with cells that have inactive nucleoli made up almost

  1. Delineation of the wheat Tsn1 candidate gene region

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The wheat Tsn1 gene confers sensitivity to the host-selective proteinaceous toxins Ptr ToxA and SnToxA produced by the pathogenic fungi Pyrenophora tritici-repentis and Stagonospora nodorum, respectively. A positional cloning strategy is being used to clone this gene. An F2 population consisting of...

  2. Genomic prediction in CIMMYT maize and wheat breeding programs

    PubMed Central

    Crossa, J; Pérez, P; Hickey, J; Burgueño, J; Ornella, L; Cerón-Rojas, J; Zhang, X; Dreisigacker, S; Babu, R; Li, Y; Bonnett, D; Mathews, K

    2014-01-01

    Genomic selection (GS) has been implemented in animal and plant species, and is regarded as a useful tool for accelerating genetic gains. Varying levels of genomic prediction accuracy have been obtained in plants, depending on the prediction problem assessed and on several other factors, such as trait heritability, the relationship between the individuals to be predicted and those used to train the models for prediction, number of markers, sample size and genotype × environment interaction (GE). The main objective of this article is to describe the results of genomic prediction in International Maize and Wheat Improvement Center's (CIMMYT's) maize and wheat breeding programs, from the initial assessment of the predictive ability of different models using pedigree and marker information to the present, when methods for implementing GS in practical global maize and wheat breeding programs are being studied and investigated. Results show that pedigree (population structure) accounts for a sizeable proportion of the prediction accuracy when a global population is the prediction problem to be assessed. However, when the prediction uses unrelated populations to train the prediction equations, prediction accuracy becomes negligible. When genomic prediction includes modeling GE, an increase in prediction accuracy can be achieved by borrowing information from correlated environments. Several questions on how to incorporate GS into CIMMYT's maize and wheat programs remain unanswered and subject to further investigation, for example, prediction within and between related bi-parental crosses. Further research on the quantification of breeding value components for GS in plant breeding populations is required. PMID:23572121

  3. Functional properties of soy hulls supplemented wheat flour

    Microsoft Academic Search

    Faqir Muhammad Anjum; Muhammad Issa Khan; Masood Sadiq Butt; Shahzad Hussain; Muhammad Abrar

    2006-01-01

    Purpose – Almost 90 per cent of the wheat produced in Pakistan is used for chapattis and rotis preparation. Unleavened flat bread (chapattis and rotis) is staple food of Pakistani population. The present study was carried out to prepare composite flour and to assess suitable level of composition. The main aim was to introduce soy hulls as a rich source

  4. Durum wheat landraces from syria. II. patterns of variation

    Microsoft Academic Search

    A. Elings

    1991-01-01

    Phenotypic variation components were estimated with respect to days to heading, flag leaf length and width, plant height, awn and spike length, awn and spike colour, spikelets per spike and seed shrivelling of 84 Syrian durum wheat landrace populations. Multivariate patterns of variation were established through principal component analysis to describe relationships between landrace groups and regions of collection. Agroecological

  5. Effect of storage and insect infestation on the mineral and vitamin contents of wheat grain and flour.

    PubMed

    Keskin, S; Ozkaya, H

    2013-04-01

    The objective of this study was to evaluate how storage and Sitophilus granarius L. infestation affects mineral and vitamin (thiamin and riboflavin) contents of wheat grain and flour obtained from the wheat. Wheat samples were infested with nonsexed S. granarius at a rate of two adults per kilogram, and stored for 6 mo at 30 +/- 1 degrees C and 70 +/- 5% relative humidity. Every 30 d, samples of wheat were collected and evaluated for insect population, mineral, thiamin, and riboflavin contents. Flour milled from these wheat samples was also evaluated for mineral, thiamin, and riboflavin contents. None of the analyses performed on the uninfested wheat and flour samples showed any noticeable change during the storage period. The insect population of the infested wheat samples increased during the storage period. The ratio of the mineral contents to dry matter significantly increased in the infested wheat and flour samples during the infestation period, whereas thiamin and riboflavin contents considerably decreased. The feeding habits of S. granarius and the distribution of minerals and vitamins in the wheat grain caused the changes observed in the levels of these compounds. The effects of infestation were greatest in the latter stages, during which the insect population increased greatly. PMID:23786101

  6. Wheat Streak Mosaic Virus 

    E-print Network

    Morgan, Gaylon

    2005-01-26

    . Infected wheat plants normally are stunted, with leaves mottled and streaked in green-yellow, parallel and discontinuous patterns (Fig. 1). This disease?s negative impact varies from year to year depending on its severity and distribution...; in the Southern Great Plains states, crop losses due to WSMV exceed $30 million in some years but are in- significant in others. High Plains Virus High Plains Virus (HPV), occasionally called High Plains Disease, is a relatively new virus identified...

  7. Genomics of Wheat Domestication

    Microsoft Academic Search

    Carlo Pozzi; Francesco Salamini

    The review covers several issues concerning the state of molecular knowledge of the effects induced by domestication and breeding\\u000a on the wheat crop. Genes at the root of the domestication syndrome are currently the focus of an active research which frequently\\u000a uses comparative genomics approaches. Conclusions drawn on available data indicate that the domestication syndrome is originated\\u000a by “sudden” genetic

  8. Desarrollo folicular y tasa ovulatoria en cabras criollas después de un periodo corto de consumo de trigo protegido de la degradación ruminal Follicular development and ovulation rate in Creole goats after short- term consumption of wheat protected from ruminal degradation

    Microsoft Academic Search

    Xochitl Pastrana Martínez; Martín Ramírez Sánchez; Juan López; Eugenio Villagómez; Everardo González Padilla; Héctor Raymundo Vera Ávila

    To determine ovarian effects after consumption of wheat protected from ruminal degradation, 40 Creole female goats received for 11 d before a synchronized estrous, 33.2 g\\/kg.75 of durum wheat treated with 5 % formaldehyde and mixed with 15 % saponified tallow (TW, n=20) or milled durum wheat and separately 15 % saponified tallow (NTW, n=20). Ovarian follicular populations were characterized

  9. Aggregation and mortality of Agriotes obscurus (Coleoptera: Elateridae) at insecticide-treated trap crops of wheat.

    PubMed

    Vernon, Robert S

    2005-12-01

    Agriotes obscurus (L.) wireworms assembled in increasing numbers at rows of treated (Agrox DL Plus seed treatment) and untreated wheat, Triticum aestivum L., planted at increasing densities (0, 0.15, 0.30, and 0.60 seeds/cm). In treated wheat plots at all planting densities, no wireworm damage to seedlings was apparent, and total wireworms taken in core samples in wheat rows increased according to the asymptotic equation y = B0(1 -e(-Blx)), where B0 is the asymptote, B1 is the slope of the initial rise, and x is the seeding density. The number of dead wireworms in treated plots increased linearly and intercepted the asymptotic models (theoretical point at which 100% mortality of assembled population occurs) at 0.95 seeds/cm on 11 June and 1.14 seeds/cm on 18 June 1996. Untreated wheat at all densities planted had severe wireworm damage and significantly reduced stand. Populations that had assembled at the surviving untreated wheat were fewer than in the treated wheat plots, and although increasing with seeding density, did not follow the asymptotic model. The data suggest that A. obscurus populations can be assembled and killed in fallowed fields in large numbers at treated trap crops of wheat over a 19-d period when planted in rows spaced 1 m apart at a linear seeding density of 1.5 seeds/cm. PMID:16539125

  10. Development,Identification and Validation of Markers for Mmarker-Assisted Selection Against the Stagonospora nodorum Toxin Ssensitivity Genes Tsn1 and Snn2 in Wheat

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The wheat-Stagonospora nodorum pathosystem involves a number of pathogen-produced host-selective toxins that interact with host genes in an inverse gene-for-gene manner to cause disease. The wheat intervarietal recombinant inbred population derived from BR34 and Grandin (BG population) segregates f...

  11. Evolution and Acceleration of No-till Farming in Rice-Wheat Cropping System of the Indo-Gangetic Plains

    Microsoft Academic Search

    Ram K. Malik; Ashok Yadav; Gurjeet S. Gill; Parveen Sardana; Raj Kumar Gupta; Colin Piggin

    The major challenge facing the rice-wheat cropping system in India is to sustain its long-term productivity. There are signs that the productivity and economic gains of this cropping system are consistently becoming smaller. For a populous country like India such a slow down amounts to food insecurity. One reason for the slow down in the growth of wheat productivity during

  12. Preliminary assessment of resistance among U.S. wheat cultivars to the Triticum pathotype of Magnaporthe oryzae

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Magnaporthe oryzae is the causal agent of blast disease on several graminaceous plants. The M. oryzae population causing wheat blast has not been officially reported outside South America. U.S. wheat production is at risk to this pathogen if it is introduced and established. Proactive testing of U.S...

  13. How does wheat resistance mediated by H genes prevent manipulation of cell development by Hessian fly larvae?

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The larva of the Hessian fly, Mayetiola destructor (Say) (Diptera: Cecidomyiidae), induces a gall nutritive tissue in susceptible wheat Triticum aestivum L. The nutritive tissue acts as a resource sink within the wheat seedling and causes serious crop losses. Hessian fly populations have been succes...

  14. Group 3 Chromosome Bin Maps of Wheat and Their Relationship to Rice Chromosome 1

    PubMed Central

    Munkvold, J. D.; Greene, R. A.; Bermudez-Kandianis, C. E.; La Rota, C. M.; Edwards, H.; Sorrells, S. F.; Dake, T.; Benscher, D.; Kantety, R.; Linkiewicz, A. M.; Dubcovsky, J.; Akhunov, E. D.; Dvo?ák, J.; Miftahudin; Gustafson, J. P.; Pathan, M. S.; Nguyen, H. T.; Matthews, D. E.; Chao, S.; Lazo, G. R.; Hummel, D. D.; Anderson, O. D.; Anderson, J. A.; Gonzalez-Hernandez, J. L.; Peng, J. H.; Lapitan, N.; Qi, L. L.; Echalier, B.; Gill, B. S.; Hossain, K. G.; Kalavacharla, V.; Kianian, S. F.; Sandhu, D.; Erayman, M.; Gill, K. S.; McGuire, P. E.; Qualset, C. O.; Sorrells, M. E.

    2004-01-01

    The focus of this study was to analyze the content, distribution, and comparative genome relationships of 996 chromosome bin-mapped expressed sequence tags (ESTs) accounting for 2266 restriction fragments (loci) on the homoeologous group 3 chromosomes of hexaploid wheat (Triticum aestivum L.). Of these loci, 634, 884, and 748 were mapped on chromosomes 3A, 3B, and 3D, respectively. The individual chromosome bin maps revealed bins with a high density of mapped ESTs in the distal region and bins of low density in the proximal region of the chromosome arms, with the exception of 3DS and 3DL. These distributions were more localized on the higher-resolution group 3 consensus map with intermediate regions of high-mapped-EST density on both chromosome arms. Gene ontology (GO) classification of mapped ESTs was not significantly different for homoeologous group 3 chromosomes compared to the other groups. A combined analysis of the individual bin maps using 537 of the mapped ESTs revealed rearrangements between the group 3 chromosomes. Approximately 232 (44%) of the consensus mapped ESTs matched sequences on rice chromosome 1 and revealed large- and small-scale differences in gene order. Of the group 3 mapped EST unigenes ?21 and 32% matched the Arabidopsis coding regions and proteins, respectively, but no chromosome-level gene order conservation was detected. PMID:15514041

  15. Group 3 chromosome bin maps of wheat and their relationship to rice chromosome 1.

    PubMed

    Munkvold, J D; Greene, R A; Bermudez-Kandianis, C E; La Rota, C M; Edwards, H; Sorrells, S F; Dake, T; Benscher, D; Kantety, R; Linkiewicz, A M; Dubcovsky, J; Akhunov, E D; Dvorák, J; Miftahudin; Gustafson, J P; Pathan, M S; Nguyen, H T; Matthews, D E; Chao, S; Lazo, G R; Hummel, D D; Anderson, O D; Anderson, J A; Gonzalez-Hernandez, J L; Peng, J H; Lapitan, N; Qi, L L; Echalier, B; Gill, B S; Hossain, K G; Kalavacharla, V; Kianian, S F; Sandhu, D; Erayman, M; Gill, K S; McGuire, P E; Qualset, C O; Sorrells, M E

    2004-10-01

    The focus of this study was to analyze the content, distribution, and comparative genome relationships of 996 chromosome bin-mapped expressed sequence tags (ESTs) accounting for 2266 restriction fragments (loci) on the homoeologous group 3 chromosomes of hexaploid wheat (Triticum aestivum L.). Of these loci, 634, 884, and 748 were mapped on chromosomes 3A, 3B, and 3D, respectively. The individual chromosome bin maps revealed bins with a high density of mapped ESTs in the distal region and bins of low density in the proximal region of the chromosome arms, with the exception of 3DS and 3DL. These distributions were more localized on the higher-resolution group 3 consensus map with intermediate regions of high-mapped-EST density on both chromosome arms. Gene ontology (GO) classification of mapped ESTs was not significantly different for homoeologous group 3 chromosomes compared to the other groups. A combined analysis of the individual bin maps using 537 of the mapped ESTs revealed rearrangements between the group 3 chromosomes. Approximately 232 (44%) of the consensus mapped ESTs matched sequences on rice chromosome 1 and revealed large- and small-scale differences in gene order. Of the group 3 mapped EST unigenes approximately 21 and 32% matched the Arabidopsis coding regions and proteins, respectively, but no chromosome-level gene order conservation was detected. PMID:15514041

  16. Mapping a gene conferring resistance to Wheat yellow mosaic virus in European winter wheat cultivar `Ibis'

    E-print Network

    Murray, Timothy D.

    Mapping a gene conferring resistance to Wheat yellow mosaic virus in European winter wheat cultivar Springer Science+Business Media B.V. 2010 Abstract Wheat yellow mosaic, caused by Wheat yellow mosaic virus (WYMV), is one of the most devastating soil-borne diseases of winter wheat (Trit- icum aestivum L

  17. Registration of Vision 40 Wheat

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The potential exists to develop and market hard winter wheat (Triticum aestivum L.) in the eastern United States, where a majority of the mills, bakeries, and consumers reside. The primary objective of this study was to develop adapted and competitive hard winter wheat cultivars possessing high-valu...

  18. Registration of 'Bill Brown' wheat

    Technology Transfer Automated Retrieval System (TEKTRAN)

    'Bill Brown’ (Reg. No. CV-133, PI 653260) hard red winter wheat (Triticum aestivum L.) was developed by the Colorado Agricultural Experiment Station and released in August 2007 through an exclusive marketing agreement with the Colorado Wheat Research Foundation. In addition to researchers at Colorad...

  19. Registration of 'Thunder CL' Wheat

    Technology Transfer Automated Retrieval System (TEKTRAN)

    'Thunder CL' (Reg. No. CV- , PI XXXXXX) hard white winter wheat (Triticum aestivum L.) was developed by the Colorado Agricultural Experiment Station and released in August 2008 through a marketing agreement with the Colorado Wheat Research Foundation. In addition to researchers at Colorado State Uni...

  20. Genome size variation in diploid and tetraploid wild wheats

    PubMed Central

    Özkan, Hakan; Tuna, Metin; Kilian, Benjamin; Mori, Naoki; Ohta, Shoji

    2010-01-01

    Background and aims Intra- and interspecific variations of C-values and the relationship between habitat factors and genome size were studied in natural populations of diploid and tetraploid wild wheats. Methodology The 1C nuclear DNA content of 376 individual plants representing 41 populations of diploid and tetraploid wild wheats was determined by flow cytometry (FCM) and correlated with geographical and bioclimate variables. Principal results Based on analysis of variance, significant differences between diploid and tetraploid Triticum species were found. Differences among populations of T. boeoticum and T. dicoccoides were also statistically significant and argue for isolation between populations, except for T. araraticum. However, the variation among individuals of the same population was not statistically significant. Maximum genome size differences among populations for T. boeoticum (0.143 pg; 2.32 %), T. dicoccoides (0.314 pg; 2.49 %) and T. araraticum (0.116 pg; 0.98 %) argue for genome constancy in these species. There was no significant correlation between intra-population variance and geographical and bioclimate variables for T. boeoticum and T. dicoccoides. In contrast to the limited genome size variation at the intraspecific level, the interspecific variation was large: ?0.5 pg/1C (8 %) at the diploid level (T. boeoticum vs. T. urartu) and ?1 pg/1C (9.7 %) at the tetraploid level (T. dicoccoides vs. T. araraticum). Conclusions Low intraspecific genome size variation occurs in diploid and tetraploid wild wheats, and this limited variation is not correlated with geographical and climate variables. However, interspecific variation is significant at the diploid and tetraploid level. It can be concluded that the genome size of wild self-fertilizing Triticum species is generally stable, despite the presence of many potentially active retroelements. In natural habitats, it is very difficult to distinguish wild wheats from each other. However, all four species can be distinguished easily, quickly and unambiguously by using the FCM technique. PMID:22476073

  1. Specific genetic markers for wheat, spelt, and four wild relatives: comparison of isozymes, RAPDs, and wheat microsatellites.

    PubMed

    Guadagnuolo, R; Bianchi, D S; Felber, F

    2001-08-01

    Three types of markers-isozymes, RAPDs (random amplified polymorphic DNAs), and wheat microsatellites- were tested on wheat, spelt, and four wild wheat relatives (Aegilops cylindrica, Elymus caninus, Hordeum marinum, and Agropyron junceum). The aim was to evaluate their capability to provide specific markers for differentiation of the cultivated and wild species. The markers were set up for subsequent detection of hybrids and introgression of wheat DNA into wild relatives. All markers allowed differentiation of the cultivated from the wild species. Wheat microsatellites were not amplified in all the wild relatives, whereas RAPDs and isozymes exhibited polymorphism for all species. The dendrograms obtained with RAPD and isozyme data separated Swiss wheat cultivars from those collected in Austria and England, while no difference was found between Swiss spelt and wheat. RAPD data provided a weak discrimination between English and Austrian E. caninus. The microsatellite-based dendrogram discriminated populations of Ae. cylindrica, but no clear separation of H. marinum from E. caninus was revealed. The similarity matrices based on the three different sets of data were strongly correlated. The highest value was recorded between the matrices based on RAPDs and isozymes (Mantel's test, r = 0.93). Correlations between the similarity matrix based on microsatellites and matrices based on RAPDs and isozymes were lower: 0.74 and 0.68, respectively. While microsatellites are very useful for comparisons of closely related accessions, they are less suitable for studies involving less-related taxa. Isozymes provide interesting markers for species differentiation, but their use seems less appropriate for studies of within-species genetic variation. RAPDs can produce a large set of markers, which can be used for the evaluation of both between- and within-species genetic variation, more rapidly and easily than isozymes and microsatellites. PMID:11550895

  2. Varietal Trials Results Wheat, Hard Red Winter

    E-print Network

    Thomas, David D.

    Varietal Trials Results Wheat, Hard Red Winter 47 Winter wheat varieties were compared in trial plots at Crookston, Lamberton, Roseau and St. Paul. Wheat varieties were grown in replicated plots. These winter wheat trials are not designed for crop (species) compar- isons because the various crops are grown

  3. BREEDING WHEAT FOR RESISTANCE TO INSECTS

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Host-plant resistance plays an important role in the management of the insect pests of wheat (Triticum sp.). Five pests, Hessian fly (Mayetiola destructor), Russian wheat aphid (Diuraphis noxia), wheat midge (Sitodiplosis mosellana), greenbug (Schizaphis graminum) and the wheat stem sawfly (Cephus s...

  4. Wheat Production in Texas. 

    E-print Network

    Atkins, I. M.; Porter, K. B.; Lahr, Keith; Merkle, Owen G.; Futrell, M. C.

    1960-01-01

    susceptible to stem rust but usually es- capes damage because of its early maturity. Vermillion is a sister strain of Knox wheat. Its yield record is equal to that of Knox and re- cently has been introduced to the State by com- mercial seedsmen... are satisfactory but Concho and Tascosa may be damaged seriously by the !+usts. Vermillion, Knox and Frisco are moder- ately resistant to leaf rust and also may escape damage because of their earliness. AREA 4 Area 4 of Central Texas differs from area 3...

  5. Using multi-spectral imagery to detect and map stress induced by Russian wheat aphid

    NASA Astrophysics Data System (ADS)

    Backoulou, Georges Ferdinand

    Scope and Method of Study. The rationale of this study was to assess the stress in wheat field induced by the Russian wheat aphid using multispectral imagery. The study was conducted to (a) determine the relationship between RWA and edaphic and topographic factors; (b) identify and quantify the spatial pattern of RWA infestation within wheat fields; (c) differentiate the stress induced by RWA from other stress causing factors. Data used for the analysis included RWA population density from the wheat field in, Texas, Colorado, Wyoming, and Nebraska, Digital Elevation Model from the Unites States Geological Survey (USGS), soil data from the Soil Survey Geographic database (SSURGO), and multispectral imagery acquired in the panhandle of Oklahoma. Findings and Conclusions. The study revealed that the population density of the Russian wheat aphid was related to topographic and edaphic factors. Slope and sand were predictor variables that were positively related to the density of RWA at the field level. The study has also demonstrated that stress induced by the RWA has a specific spatial pattern that can be distinguished from other stress causing factors using a combination of landscape metrics and topographic and edaphic characteristics of wheat fields. Further field-based studies using multispectral imagery and spatial pattern analysis are suggested. The suggestions require acquiring biweekly multispectral imagery and collecting RWA, topographic and edaphic data at the sampling points during the phonological growth development of wheat plants. This is an approach that may pretend to have great potential for site specific technique for the integrated pest management.

  6. Seasonal Dynamics of Cereal Aphids on Russian Wheat Aphid (Homoptera: Aphididae) Susceptible and Resistant Wheats

    Microsoft Academic Search

    Dennis J. Schotzko; Nilsa A. Bosque-Pérez

    2000-01-01

    Field experiments were conducted in 1997 and 1998 to evaluate the impact of resistance to Russian wheat aphid, Diuraphis noxia (Mordvilko), on the cereal aphid complex in wheat. Two spring wheats were planted: the variety \\

  7. Drought tolerance in wheat.

    PubMed

    Nezhadahmadi, Arash; Prodhan, Zakaria Hossain; Faruq, Golam

    2013-01-01

    Drought is one of the most important phenomena which limit crops' production and yield. Crops demonstrate various morphological, physiological, biochemical, and molecular responses to tackle drought stress. Plants' vegetative and reproductive stages are intensively influenced by drought stress. Drought tolerance is a complicated trait which is controlled by polygenes and their expressions are influenced by various environmental elements. This means that breeding for this trait is so difficult and new molecular methods such as molecular markers, quantitative trait loci (QTL) mapping strategies, and expression patterns of genes should be applied to produce drought tolerant genotypes. In wheat, there are several genes which are responsible for drought stress tolerance and produce different types of enzymes and proteins for instance, late embryogenesis abundant (lea), responsive to abscisic acid (Rab), rubisco, helicase, proline, glutathione-S-transferase (GST), and carbohydrates during drought stress. This review paper has concentrated on the study of water limitation and its effects on morphological, physiological, biochemical, and molecular responses of wheat with the possible losses caused by drought stress. PMID:24319376

  8. Molecular approaches for characterization and use of natural disease resistance in wheat

    Microsoft Academic Search

    Navreet Kaur; Michael Mackay; Nabila Yahiaoui; Beat Keller

    Wheat production is threatened by a constantly changing population of pathogen species and races. Given the rapid ability\\u000a of many pathogens to overcome genetic resistance, the identification and practical implementation of new sources of resistance\\u000a is essential. Landraces and wild relatives of wheat have played an important role as genetic resources for the improvement\\u000a of disease resistance. The use of

  9. Molecular approaches for characterization and use of natural disease resistance in wheat

    Microsoft Academic Search

    Navreet Kaur; Michael Mackay; Nabila Yahiaoui; Beat Keller

    2008-01-01

    Wheat production is threatened by a constantly changing population of pathogen species and races. Given the rapid ability\\u000a of many pathogens to overcome genetic resistance, the identification and practical implementation of new sources of resistance\\u000a is essential. Landraces and wild relatives of wheat have played an important role as genetic resources for the improvement\\u000a of disease resistance. The use of

  10. Estimating climate change, CO2 and technology development effects on wheat yield in northeast Iran.

    PubMed

    Bannayan, M; Mansoori, H; Rezaei, E Eyshi

    2014-04-01

    Wheat is the main food for the majority of Iran's population. Precise estimation of wheat yield change in future is essential for any possible revision of management strategies. The main objective of this study was to evaluate the effects of climate change, CO2 concentration, technology development and their integrated effects on wheat production under future climate change. This study was performed under two scenarios of the IPCC Special Report on Emission Scenarios (SRES): regional economic (A2) and global environmental (B1). Crop production was projected for three future time periods (2020, 2050 and 2080) in comparison with a baseline year (2005) for Khorasan province located in the northeast of Iran. Four study locations in the study area included Mashhad, Birjand, Bojnourd and Sabzevar. The effect of technology development was calculated by fitting a regression equation between the observed wheat yields against historical years considering yield potential increase and yield gap reduction as technology development. Yield relative increase per unit change of CO2 concentration (1 ppm(-1)) was considered 0.05 % and was used to implement the effect of elevated CO2. The HadCM3 general circulation model along with the CSM-CERES-Wheat crop model were used to project climate change effects on wheat crop yield. Our results illustrate that, among all the factors considered, technology development provided the highest impact on wheat yield change. Highest wheat yield increase across all locations and time periods was obtained under the A2 scenario. Among study locations, Mashhad showed the highest change in wheat yield. Yield change compared to baseline ranged from -28 % to 56 % when the integration of all factors was considered across all locations. It seems that achieving higher yield of wheat in future may be expected in northeast Iran assuming stable improvements in production technology. PMID:23397072

  11. Aphid Feeding Activates Expression of a Transcriptome of Oxylipin-based Defense Signals in Wheat Involved in Resistance to Herbivory

    Microsoft Academic Search

    Charles Michael Smith; Xuming Liu; Liang J. Wang; Xiang Liu; Ming-Shun Chen; Sharon Starkey; Jianfa Bai

    2010-01-01

    Damage by the Russian wheat aphid (RWA), Diuraphis noxia, significantly reduces wheat and barley yields worldwide. In compatible interactions, virulent RWA populations flourish and\\u000a susceptible plants suffer extensive leaf chlorophyll loss. In incompatible interactions, RWA reproduction and population growth\\u000a are significantly reduced and RWA-related chlorophyll loss in resistant plants is minor. The objectives of this study were\\u000a to develop an

  12. Whole Wheat Pizza Dough Ingredients

    E-print Network

    Liskiewicz, Maciej

    /4 teaspoon salt 1 teaspoon sugar 1 package yeast, quick rise 2/3 cup hot water 1 tablespoon olive oil. Blend yeast with flour mixture. Add hot water; stir to form dough. 3. Add enough whole wheat flour

  13. Endosperm tolerance of paternal aneuploidy allows radiation hybrid mapping of the wheat D-genome and a measure of ? ray-induced chromosome breaks.

    PubMed

    Tiwari, Vijay K; Riera-Lizarazu, Oscar; Gunn, Hilary L; Lopez, Kasandra; Iqbal, M Javed; Kianian, Shahryar F; Leonard, Jeffrey M

    2012-01-01

    Physical mapping and genome sequencing are underway for the ?17 Gb wheat genome. Physical mapping methods independent of meiotic recombination, such as radiation hybrid (RH) mapping, will aid precise anchoring of BAC contigs in the large regions of suppressed recombination in Triticeae genomes. Reports of endosperm development following pollination with irradiated pollen at dosages that cause embryo abortion prompted us to investigate endosperm as a potential source of RH mapping germplasm. Here, we report a novel approach to construct RH based physical maps of all seven D-genome chromosomes of the hexaploid wheat 'Chinese Spring', simultaneously. An 81-member subset of endosperm samples derived from 20-Gy irradiated pollen was genotyped for deletions, and 737 markers were mapped on seven D-genome chromosomes. Analysis of well-defined regions of six chromosomes suggested a map resolution of ?830 kb could be achieved; this estimate was validated with assays of markers from a sequenced contig. We estimate that the panel contains ?6,000 deletion bins for D-genome chromosomes and will require ?18,000 markers for high resolution mapping. Map-based deletion estimates revealed a majority of 1-20 Mb interstitial deletions suggesting mutagenic repair of double-strand breaks in pollen provides a useful resource for RH mapping and map based cloning studies. PMID:23144983

  14. Genetic Diversity and Grain Protein Composition of Tetraploid Wheat

    E-print Network

    Genetic Diversity and Grain Protein Composition of Tetraploid Wheat (Triticum durum Desf wheat and kernels of durum wheat #12;Genetic diversity and grain protein composition of tetraploid wheat in landraces of tetraploid wheat germplasm collected from major wheat-producing regions of Ethiopia were

  15. Dough Rheology and Wet Milling of Hard Waxy Wheat Flours

    Technology Transfer Automated Retrieval System (TEKTRAN)

    To realize the full potential of waxy wheat (Triticum aestivum L.), wet milling of waxy wheat flour to produce gluten and waxy wheat starch was investigated. Flours of six advanced lines of waxy hard wheats, one normal hard wheat (‘Karl 92’), and one partial waxy wheat (‘Trego’) were fractionated by...

  16. Applications of Suits spectral model to wheat

    NASA Technical Reports Server (NTRS)

    Chance, J. E.

    1977-01-01

    Canopy reflectance calculations for a spring type Mexican wheat, Penjamo, are compared with published data on Scout winter wheat. Good agreement exists between model calculations and experimental data in the spectral range, 500 nm to 750 nm, suggesting that the model parameters for wheat can be applied to different cultivars of wheat in the same growth stage. Wheat canopy reflectance is dependent upon surface soil type and this dependency is examined with the Suits' spectral model. In this particular growth stage wheat reflectance is shown to be nearly independent of soil reflectance in the visible wavelengths and progressively dependent at longer wavelengths in the infrared.

  17. Climate change induced rainfall patterns affect wheat productivity and agroecosystem functioning dependent on soil types

    NASA Astrophysics Data System (ADS)

    Tabi Tataw, James; Baier, Fabian; Krottenthaler, Florian; Pachler, Bernadette; Schwaiger, Elisabeth; Whylidal, Stefan; Formayer, Herbert; Hösch, Johannes; Baumgarten, Andreas; Zaller, Johann G.

    2014-05-01

    Wheat is a crop of global importance supplying more than half of the world's population with carbohydrates. We examined, whether climate change induced rainfall patterns towards less frequent but heavier events alter wheat agroecosystem productivity and functioning under three different soil types. Therefore, in a full-factorial experiment Triticum aestivum L. was cultivated in 3 m2 lysimeter plots containing the soil types sandy calcaric phaeozem, gleyic phaeozem or calcic chernozem. Prognosticated rainfall patterns based on regionalised climate change model calculations were compared with current long-term rainfall patterns; each treatment combination was replicated three times. Future rainfall patterns significantly reduced wheat growth and yield, reduced the leaf area index, accelerated crop development, reduced arbuscular mycorrhizal fungi colonisation of roots, increased weed density and the stable carbon isotope signature (?13C) of both old and young wheat leaves. Different soil types affected wheat growth and yield, ecosystem root production as well as weed abundance and biomass. The interaction between climate and soil type was significant only for the harvest index. Our results suggest that even slight changes in rainfall patterns can significantly affect the functioning of wheat agroecosystems. These rainfall effects seemed to be little influenced by soil types suggesting more general impacts of climate change across different soil types. Wheat production under future conditions will likely become more challenging as further concurrent climate change factors become prevalent.

  18. Reflectance characteristics of Russian wheat aphid (Hemiptera: Aphididae) stress and abundance in winter wheat

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The Russian wheat aphid (Diuraphis noxia (Mordvilko)) infests wheat (Triticum aestivum L.), barley (Hordeum vulgare L.), and other small grains and grasses. Russian wheat aphid infestations are unpredictable in time and space. In favorable conditions, Russian wheat aphid feeding can result in heavy...

  19. Registration of `Bauermeister' Wheat `Bauermeister' (J981107, WA007939) hard red winter wheat

    E-print Network

    Murray, Timothy D.

    Registration of `Bauermeister' Wheat `Bauermeister' (J981107, WA007939) hard red winter wheat (HRW cultivar adapted to the low- to intermediate-rainfall (, 460 mm average annual precipitation) HRW wheat, and excellent quality attributes. Bauermeister is named in honor of Dale and Dan Bauermeister, wheat producers

  20. Wheat and Stocker Cattle Production Stocker cattle grazing wheat pasture is an important

    E-print Network

    Wheat and Stocker Cattle Production Challenges Stocker cattle grazing wheat pasture is an important part of the economy in the Texas Rolling Plains region. Wheat and stocker cattle business decisions are impacted by a variety of issues, including cattle and wheat prices, animal health, weather

  1. Multiplication of soilborne wheat mosaic virus (SBWMV) in wheat roots infected by a soil

    E-print Network

    Paris-Sud XI, Université de

    Multiplication of soilborne wheat mosaic virus (SBWMV) in wheat roots infected by a soil carrying SBWMV and wheat yellow mosaic virus (WYMV) Djabbar HARIRI, Michel COURTILLOT Pascal ZAOUI, Hervé winter wheat cultivars were infected in the field or in a growth chamber with an inoculum consisting

  2. EVALUATION OF DURUM SPRING WHEAT SUSCEPTIBILITY TO WHEAT STEM SAWFLY (HYMENOPTERA: CEPHIDAE)

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The wheat stem sawfly, Cephus cinctus Norton, is the primary arthropod pest of wheat, Triticum aestivum, in the Northern Great Plains. Rotation to non-host crops should decrease infestation of susceptible spring or winter wheats. Information is unavailable on wheat stem sawfly infestation potentia...

  3. SURVIVAL OF WHEAT CURL MITES ON DIFFERENT SOURCES OF RESISTANCE IN WHEAT

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Wheat yield is limited by wheat streak mosaic virus which is vectored by the wheat curl mite (WCM) Aceria tosicheilla (Keifer).Host resistance to WCM has reduced losses. This study evaluated the effectiveness of resistance in wheat to WCM collected from various locations in the Great Plains. Collect...

  4. Ethanol production from mixtures of wheat straw and wheat meal

    PubMed Central

    2010-01-01

    Background Bioethanol can be produced from sugar-rich, starch-rich (first generation; 1G) or lignocellulosic (second generation; 2G) raw materials. Integration of 2G ethanol with 1G could facilitate the introduction of the 2G technology. The capital cost per ton of fuel produced would be diminished and better utilization of the biomass can be achieved. It would, furthermore, decrease the energy demand of 2G ethanol production and also provide both 1G and 2G plants with heat and electricity. In the current study, steam-pretreated wheat straw (SPWS) was mixed with presaccharified wheat meal (PWM) and converted to ethanol in simultaneous saccharification and fermentation (SSF). Results Both the ethanol concentration and the ethanol yield increased with increasing amounts of PWM in mixtures with SPWS. The maximum ethanol yield (99% of the theoretical yield, based on the available C6 sugars) was obtained with a mixture of SPWS containing 2.5% water-insoluble solids (WIS) and PWM containing 2.5% WIS, resulting in an ethanol concentration of 56.5 g/L. This yield was higher than those obtained with SSF of either SPWS (68%) or PWM alone (91%). Conclusions Mixing wheat straw with wheat meal would be beneficial for both 1G and 2G ethanol production. However, increasing the proportion of WIS as wheat straw and the possibility of consuming the xylose fraction with a pentose-fermenting yeast should be further investigated. PMID:20598120

  5. Stress-induced changes in wheat grain composition and quality.

    PubMed

    Ashraf, M

    2014-01-01

    Abiotic stresses such as drought, salinity, waterlogging, and high temperature cause a myriad of changes in the metabolism of plants, and there is a lot of overlap in these changes in plants in response to different stresses such as drought and salinity. These stress-induced metabolic changes cause impaired crop growth thereby resulting in poor yield. The metabolic changes taking place in several plant species due to a particular abiotic stress have been revealed from the whole plant to the molecular level by researchers, but most studies have focused on organs such as leaf, stem, and root. Information on such stress-induced changes in seed or grains is infrequent in the literature. From the information that is available, it is now evident that abiotic stress can induce considerable changes in the composition and quality of cereal grains including those of wheat, the premier staple food crop in the world. Thus, the present review discusses how far different types of stresses, mainly salinity, drought, high temperature, and waterlogging, can alter the wheat grain composition and quality. By fully uncovering the stress-induced changes in the nutritional values of wheat grains it would be possible to establish whether balanced supplies of essential nutrients are available to the human population from the wheat crop grown on stress-affected areas. PMID:24580559

  6. Associations of wheat with pea can reduce aphid infestations.

    PubMed

    Lopes, T; Bodson, B; Francis, F

    2015-06-01

    Increasing plant diversity within crops can be beneficial for pest control. In this field study, the effects of two wheat and pea associations (mixed cropping and strip cropping) on aphid populations were compared with pure stands of both crops by observations on tillers and plants. Pea was more susceptible to infestations than wheat. As expected, the density of aphid colonies was significantly higher in pure stands during the main occurrence periods, compared with associations. Additionally, flying beneficials, such as not only aphidophagous adult ladybirds but also parasitoid, hoverfly and lacewing species that feed on aphids at the larval stage, were monitored using yellow pan traps. At specific times of the sampling season, ladybirds and hoverflies were significantly more abundant in the pure stand of pea and wheat, respectively, compared with associations. Few parasitoids and lacewings were trapped. This study showed that increasing plant diversity within crops by associating cultivated species can reduce aphid infestations, since host plants are more difficult to locate. However, additional methods are needed to attract more efficiently adult beneficials into wheat and pea associations. PMID:26013274

  7. Evolution of bacterial communities in the wheat crop rhizosphere.

    PubMed

    Donn, Suzanne; Kirkegaard, John A; Perera, Geetha; Richardson, Alan E; Watt, Michelle

    2015-03-01

    The gap between current average global wheat yields and that achievable through best agronomic management and crop genetics is large. This is notable in intensive wheat rotations which are widely used. Expectations are that this gap can be reduced by manipulating soil processes, especially those that involve microbial ecology. Cross-year analysis of the soil microbiome in an intensive wheat cropping system revealed that rhizosphere bacteria changed much more than the bulk soil community. Dominant factors influencing populations included binding to roots, plant age, site and planting sequence. We demonstrated evolution of bacterial communities within the field rhizosphere. Early in the season, communities tightly bound to the root were simplest. These increased in diversity with plant age and senescence. Loosely bound communities also increased in diversity from vegetative to reproductive plant stages but were more stable than those tightly bound to roots. Planting sequence and, to a lesser extent, wheat genotype also significantly affected rhizosphere bacteria. Plasticity in the rhizosphere generated from crop root system management and genetics offers promise for manipulating the soil ecology of intense cereal systems. Analyses of soil microbiomes for the purpose of developing agronomic benefit should include roots as well as soil loosely adhered to the roots, and the bulk soil. PMID:24628845

  8. Identification of a hybridization window that facilitates sizeable reductions of pollen-mediated gene flow in spring wheat.

    PubMed

    Willenborg, Christian J; Brûlé-Babel, Anita L; Van Acker, Rene C

    2010-06-01

    Transgenic wheat (Triticum aestivum L.) with improved agronomic traits is currently being field-tested. Gene flow in space is well-documented, but isolation in time has not received comparable attention. Here, we report the results of a field experiment that investigated reductions in intraspecific gene flow associated with temporal isolation of flowering between T. aestivum conspecifics. Pollen-mediated gene flow (PMGF) between an imazamox-resistant (IR) volunteer wheat population and a non-IR spring wheat crop was assessed over a range of volunteer emergence timings and plant population densities that collectively promoted flowering asynchrony. Natural hybridization events between the two populations were detected by phenotypically scoring plants in F(1) populations followed by verification with Mendelian segregation ratios in the F(1:2) lines. Based on the examination of >545,000 seedlings, we identified a hybridization window in spring wheat approximately 125 growing degree-days (GDD) in length. We found a sizeable reduction (two- to four-fold) in gene flow frequencies when flowering occurred outside of this window. The hybridization window identified in this research also will serve to temporally isolate neighboring wheat crops. However, strict control of volunteer populations or spatial isolation of neighbouring crops emerging within a 125 GDD hybridization window will be necessary to maintain low frequencies of PMGF in spring wheat fields. The model developed herein also is likely to be applicable to other wind-pollinated species. PMID:19763864

  9. Expression of a Thatcher wheat adult plant stem rust resistance QTL on chromosome arm 2BL is enhanced by Lr34

    Technology Transfer Automated Retrieval System (TEKTRAN)

    An F6 recombinant inbred line (RIL) spring wheat population derived from RL6071, a stem rust susceptible line and RL6058, a backcross line of Thatcher wheat with Lr34 that is highly resistant to stem rust, was evaluated for adult plant stem rust resistance in North Dakota in 1999, and in Kenya in 20...

  10. Wheat Curl Mite and Wheat Streak Mosaic Virus Spread from Volunteer Wheat Figure 2. Spectral profiles at three points identified in Figure

    E-print Network

    Nebraska-Lincoln, University of

    Wheat Curl Mite and Wheat Streak Mosaic Virus Spread from Volunteer Wheat Figure 2. Spectral Management Information Technologies (CALMIT) (apeters@calmit.unl.edu) Background: Wheat streak mosaic (WSM) is the most severe disease of winter wheat in the Great Plains. Estimates indicate WSM causes an average loss

  11. The value of wheat landraces (Editorial)

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Whether man was domesticated by wheat, or wheat was domesticated by man is but two faces of the same coin; both incidents marked a turning point in human history and led to the emergence of human civilization in the Fertile Crescent of the Old World. The complex history of wheat domestication from i...

  12. Hard Spring Wheat Technical Committee, 2008 Crop.

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Eleven hard spring wheat lines that were developed by breeders throughout the spring wheat region of the U. S. were grown at up to five locations in 2008 and evaluated for kernel, milling, and bread baking quality against the check variety Glenn. Samples of wheat were milled at the USDA Hard Red Sp...

  13. Growing Wheat. People on the Farm.

    ERIC Educational Resources Information Center

    Department of Agriculture, Washington, DC. Office of Governmental and Public Affairs.

    This booklet, one in a series about life on modern farms, describes the daily life of the Don Riffel family, wheat farmers in Kansas. Beginning with early morning, the booklet traces the family's activities through a typical harvesting day in July, while explaining how a wheat farm is run. The booklet also briefly describes the wheat growing…

  14. CULTIVAR DESCRIPTION CDC Kestrel winter wheat

    E-print Network

    Saskatchewan, University of

    CULTIVAR DESCRIPTION CDC Kestrel winter wheat D. B. Fowler Crop Development Centre, University 17 December 1996, accepted 12 August 1997. Fowler, D. B. 1997. CDC Kestrel winter wheat. Can. J. Plant Sci. 77: 673­675. CDC Kestrel is a lodging-resistant, high-yielding, semidwarf winter wheat

  15. CULTIVAR DESCRIPTION CDC Clair winter wheat

    E-print Network

    Saskatchewan, University of

    CULTIVAR DESCRIPTION CDC Clair winter wheat D. B. Fowler Crop Development Centre, University 17 December 1996, accepted 12 August 1997. Fowler, D. B. 1997. CDC Clair winter wheat. Can. J. Plant Sci. 77: 669­671. CDC Clair is a high-yielding, strong-strawed, semi- dwarf winter wheat (Triticum

  16. Wheat Proteins Improve Cryopreservation of Rat Hepatocytes

    E-print Network

    Sarhan, Fathey

    ARTICLE Wheat Proteins Improve Cryopreservation of Rat Hepatocytes Me´lanie Grondin, Francine Hamel demonstrated that a crude wheat extract protects rat hepatocytes during cryo- preservation and could provide by using wheat extracts that are partially purified by either ammonium sulphate or acetone precipitation

  17. Disease Update in Wheat Gaylon Morgan

    E-print Network

    Mukhtar, Saqib

    Disease Update in Wheat Gaylon Morgan State Extension Small Grains Specialist March 3, 2005 There are three major foliar leaf diseases that commonly occur in Texas wheat fields, including Leaf Rust, Stripe of Powdery Mildew that occurred in 2004. Factors to Consider for Managing Foliar Diseases in Wheat: 1

  18. HEDONIC PRICE ESTIMATION FOR KANSAS WHEAT CHARACTERISTICS

    Microsoft Academic Search

    Juan Andres Espinosa; Barry K. Goodwin

    1991-01-01

    A hedonic price model is applied to a cross-sectional time-series data set of Kansas wheat characteristics. Results indicate that prices received by wheat producers reflect the presence of conventional quality characteristics of wheat and also milling and dough characteristics. Furthermore, the results indicate that the alternative sets of characteristics exhibit quality information that is, to some degree, independent of one

  19. Deciphering the genetics of flowering time by an association study on candidate genes in bread wheat (Triticum aestivum L.).

    PubMed

    Rousset, Michel; Bonnin, Isabelle; Remoué, Carine; Falque, Matthieu; Rhoné, Bénédicte; Veyrieras, Jean-Baptiste; Madur, Delphine; Murigneux, Alain; Balfourier, François; Le Gouis, Jacques; Santoni, Sylvain; Goldringer, Isabelle

    2011-10-01

    Earliness is very important for the adaptation of wheat to environmental conditions and the achievement of high grain yield. A detailed knowledge of key genetic components of the life cycle would enable an easier control by the breeders. The objective of the study was to investigate the effect of candidate genes on flowering time. Using a collection of hexaploid wheat composed of 235 lines from diverse geographical origins, we conducted an association study for six candidate genes for flowering time and its components (vernalization sensitivity and earliness per se). The effect on the variation of earliness components of polymorphisms within the copies of each gene was tested in ANOVA models accounting for the underlying genetic structure. The collection was structured in five groups that minimized the residual covariance. Vernalization requirement and lateness tend to increase according to the mean latitude of each group. Heading date for an autumnal sowing was mainly determined by the earliness per se. Except for the Constans (CO) gene orthologous of the barley HvCO3, all gene polymorphisms had a significant impact on earliness components. The three traits used to quantify vernalization requirement were primarily associated with polymorphisms at Vrn-1 and then at Vrn-3 and Luminidependens (LD) genes. We found a good correspondence between spring/winter types and genotypes at the three homeologous copies of Vrn-1. Earliness per se was mainly explained by polymorphisms at Vrn-3 and to a lesser extent at Vrn-1, Hd-1 and Gigantea (GI) genes. Vernalization requirement and earliness as a function of geographical origin, as well as the possible role of the breeding practices in the geographical distribution of the alleles and the hypothetical adaptive value of the candidate genes, are discussed. PMID:21761163

  20. Biofortification of wheat grain with iron and zinc: integrating novel genomic resources and knowledge from model crops

    PubMed Central

    Borrill, Philippa; Connorton, James M.; Balk, Janneke; Miller, Anthony J.; Sanders, Dale; Uauy, Cristobal

    2014-01-01

    Wheat, like many other staple cereals, contains low levels of the essential micronutrients iron and zinc. Up to two billion people worldwide suffer from iron and zinc deficiencies, particularly in regions with predominantly cereal-based diets. Although wheat flour is commonly fortified during processing, an attractive and more sustainable solution is biofortification, which requires developing new varieties of wheat with inherently higher iron and zinc content in their grains. Until now most studies aimed at increasing iron and zinc content in wheat grains have focused on discovering natural variation in progenitor or related species. However, recent developments in genomics and transformation have led to a step change in targeted research on wheat at a molecular level. We discuss promising approaches to improve iron and zinc content in wheat using knowledge gained in model grasses. We explore how the latest resources developed in wheat, including sequenced genomes and mutant populations, can be exploited for biofortification. We also highlight the key research and practical challenges that remain in improving iron and zinc content in wheat. PMID:24600464

  1. Origin and spread of wheat in China

    NASA Astrophysics Data System (ADS)

    Dodson, John R.; Li, Xiaoqiang; Zhou, Xinying; Zhao, Keliang; Sun, Nan; Atahan, Pia

    2013-07-01

    Wheat was added as a new crop to the existing millet and rice based agricultural systems of China. Here we present 35 radiocarbon ages from wheat seeds collected from 18 sites between western (Xinjiang Province) and eastern (Henan Province) China. The earliest wheat ages cluster around 2100-1800 BCE in northern China's Hexi corridor of Gansu Province, where millet was already a well-established crop. Wheat first appears in Xinjiang and Henan about 300-400 years later, and perhaps a little earlier than this in Xinjiang, and we hypothesize that the likely route of wheat into China was via Russia through Gansu.

  2. Diseases Which Challenge Global Wheat Production - The Cereal Rusts

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The rusts of wheat are common and widespread diseases in the US and throughout the world. Wheat rusts have been important throughout the history of wheat cultivation and are currently important diseases that are responsible for regularly occurring yield losses in wheat. The wheat rust fungi are obli...

  3. Attitudes towards the Canadian Wheat Board monopoly in Saskatchewan

    E-print Network

    Saskatchewan, University of

    Attitudes towards the Canadian Wheat Board monopoly in Saskatchewan: A research brief December 2011 to eliminate the Canadian Wheat Board (CWB)'s monopoly on the selling of all wheat, durum and barley produced' or `oppose' the Canadian Wheat Board's monopoly on selling prairie wheat, durum and barley, or do you have

  4. Wheat Rusts in the United States in 2007

    Technology Transfer Automated Retrieval System (TEKTRAN)

    In 2007 90% of wheat stem rust races were QFC and 10% were RCRS Both races are relatively avirulent to wheat cultiars grown in the U.S. Wheat stem rust occurred in scattered locations on research plots of susceptible wheat cultivars in 2007, and did not cause yield loss. Wheat leaf rust was widespr...

  5. Sex pheromone of orange wheat blossom midge, Sitodiplosis mosellana

    NASA Astrophysics Data System (ADS)

    Gries, Regine; Gries, G.; Khaskin, Grigori; King, Skip; Olfert, Owen; Kaminski, Lori-Ann; Lamb, Robert; Bennett, Robb

    Pheromone extract of the female orange wheat blossom midge, Sitodiplosis mosellana (Géhin) (SM) (Diptera: Cecidomyiidae), was analyzed by coupled gas chromatographic-electroantennographic detection (GC-EAD) and GC-mass spectrometry (MS), employing fused silica columns coated with DB-5, DB-210, DB-23 or SP-1000. These analyses revealed a single, EAD-active candidate pheromone which was identified as 2,7-nonanediyl dibutyrate. In experiments in wheat fields in Saskatchewan, traps baited with (2S,7S)-2,7-nonanediyl dibutyrate attracted significant numbers of male SM. The presence of other stereoisomers did not adversely affect trap captures. Facile synthesis of stereoisomeric 2,7-nonanediyl dibutyrate will facilitate the development of pheromone-based monitoring or even control of SM populations.

  6. Genetic structure of Tribolium castaneum (Coleptera: Tenebrionidae) populations in mills

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The red flour beetle, Tribolium castaneum, is primarily found associated with human structures such as wheat and rice mills, which are spatially isolated resource patches with apparently limited immigration that could produce genetically structured populations. We investigated genetic diversity and...

  7. 1134 PHYTOPATHOLOGY Ecology and Population Biology

    E-print Network

    McDonald, Bruce

    1134 PHYTOPATHOLOGY Ecology and Population Biology High Genetic Similarity Among PopulationsDermott, and B. A. McDonald First and second authors: Institute for Plant Sciences, Phytopathology Group, Federal in Switzerland. Phytopathology 87:1134-1139. Phaeosphaeria nodorum was sampled from nine wheat fields across a 30

  8. Registration of ‘WB3768’ wheat

    Technology Transfer Automated Retrieval System (TEKTRAN)

    ‘WB3768’ (Reg. No. CV-1100, PI 670158) hard white winter wheat (Triticum aestivum L.) was developed and released by the Montana Agricultural Experiment Station in September 2013. An exclusive license for commercialization of WB3768 was granted to Monsanto. WB3768 is of unknown pedigree, derived from...

  9. Registration of ‘UI SRG’ wheat

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Developing wheat (Triticum aestivum L.) cultivars with high yield, desirable end-use quality, and resistance to prevalent diseases are the major goals for the breeding programs in the Pacifi c Northwest region of the United States and the world. ‘UI SRG’ (Reg. No. CV-1066, PI 660546) hard red winter...

  10. REGISTRATION OF 'INFINITY CL' WHEAT

    Technology Transfer Automated Retrieval System (TEKTRAN)

    ‘Infinity CL’ (Reg. No. Cv- ) is a hard red winter wheat (Triticum aestivum L.) cultivar developed cooperatively by the Nebraska Agricultural Experiment Station and the USDA-ARS, and released in 2005 by the developing institutions. Infinity CL contains a patented gene owned by BASF Corporation. In...

  11. Registration of TAM401 wheat

    Technology Transfer Automated Retrieval System (TEKTRAN)

    'TAM 401', a hard red winter wheat (Triticum aestivum L) cultivar (PI658500) with experimental designation TX03M1096, was developed and released by Texas AgriLife Research in 2008. TAM 401 is an F4 derived line from the cross 'Mason' (PI 594044)/'Jagger' (PI593688). TAM 401 is an early maturing apic...

  12. Registration of 'Red Ruby' Wheat

    Technology Transfer Automated Retrieval System (TEKTRAN)

    ‘Red Ruby’ soft red winter wheat (Triticum aestivum L.) was developed by the Michigan Agricultural Experiment Station and released in 2007 via an exclusive licensing agreement through Michigan State University (MSU) Technologies. Red Ruby was selected from the cross Pioneer ‘2552’/Pioneer ‘2737W’ ma...

  13. Registration of 'TAM 113' wheat

    Technology Transfer Automated Retrieval System (TEKTRAN)

    ‘TAM 113’ (Reg. No. CV-1081, PI 666125), a hard red winter wheat (Triticum aestivum L.) cultivar with experimental designation TX02A0252, was developed and released by Texas AgriLife Research in 2010. TAM 113 is an F5–derived line from the cross TX90V6313/TX94V3724 made at Vernon, TX in 1995. Both T...

  14. Registration of 'Clara CL' Wheat

    Technology Transfer Automated Retrieval System (TEKTRAN)

    ‘Clara CL’ hard white winter wheat (Triticum aestivum L.) was developed at the Agricultural Research Center-Hays, Kansas State University and released by the Kansas Agricultural Experiment Station in 2011. Clara CL carries one Clearfield gene and has the tolerance to imazamox herbicide. Clara CL wa...

  15. Registration of Vision 30 Wheat

    Technology Transfer Automated Retrieval System (TEKTRAN)

    ‘Vision 30’ (Reg. No. CV-1062, PI 661153) hard red winter (HRW) wheat (Triticum aestivum L.) was developed and tested as VA06HRW-49 and released by the Virginia Agricultural Experiment Station in March 2010. Vision 30 was derived from the cross 92PAN1#33/VA97W-414. Vision 30 is high yielding, awned,...

  16. Registration of ‘UI Winchester’ Wheat

    Technology Transfer Automated Retrieval System (TEKTRAN)

    ‘UI Winchester’ (PI 642362) hard red spring wheat (Triticum aestivum L.) was developed by the Idaho Agricultural Experiment Station and released in July 2009. UI Winchester was released for its improved stripe rust (Puccinia striiformis Westend f. sp. tritici) resistance combined with resistance to ...

  17. Adapting wheat to uncertain future

    NASA Astrophysics Data System (ADS)

    Semenov, Mikhail; Stratonovitch, Pierre

    2015-04-01

    This study describes integration of climate change projections from the Coupled Model Intercomparison Project Phase 5 (CMIP5) multi-model ensemble with the LARS-WG weather generator, which delivers an attractive option for downscaling of large-scale climate projections from global climate models (GCMs) to local-scale climate scenarios for impact assessments. A subset of 18 GCMs from the CMIP5 ensemble and 2 RCPs, RCP4.5 and RCP8.5, were integrated with LARS-WG. Climate sensitivity indexes for temperature and precipitation were computed for all GCMs and for 21 regions in the world. For computationally demanding impact assessments, where it is not practical to explore all possible combinations of GCM × RCP, climate sensitivity indexes could be used to select a subset of GCMs from CMIP5 with contrasting climate sensitivity. This would allow to quantify uncertainty in impacts resulting from the CMIP5 ensemble by conducting fewer simulation experiments. As an example, an in silico design of wheat ideotype optimised for future climate scenarios in Europe was described. Two contrasting GCMs were selected for the analysis, "hot" HadGEM2-ES and "cool" GISS-E2-R-CC, along with 2 RCPs. Despite large uncertainty in climate projections, several wheat traits were identified as beneficial for the high-yielding wheat ideotypes that could be used as targets for wheat improvement by breeders.

  18. Registration of ‘Ok101’ Wheat

    Technology Transfer Automated Retrieval System (TEKTRAN)

    ‘Ok101’ (Reg. no. CV-932, PI 631493) is a hard red winter wheat (Triticum aestivum L.) developed cooperatively by the Oklahoma Agricultural Experiment Station and the USDA-ARS, and released in March 2001. Ok101 was released for its high tolerance to acidic soil, broad adaptation to both dual-purpose...

  19. REGISTRATION OF 'OK BULLET' WHEAT

    Technology Transfer Automated Retrieval System (TEKTRAN)

    ‘OK Bullet’ is a hard red winter wheat (Triticum aestivum L.) cultivar developed cooperatively by the Oklahoma Agric. Exp. Stn. (AES), USDA-ARS, and the Texas AES and released by the Oklahoma AES and the USDA-ARS in 2005. OK Bullet is recommended for grain-only and dual-purpose production systems t...

  20. Registration of 'NE01643' Wheat

    Technology Transfer Automated Retrieval System (TEKTRAN)

    NE01643 is a hard red winter wheat (Triticum aestivum L.) cultivar developed cooperatively by the Nebraska Agricultural Experiment Station and the USDA-ARS and released in 2007 by the developing institutions and the South Dakota Agricultural Experiment Station. NE01643 will be marketed under the na...

  1. Registration of ‘Ok102’ Wheat

    Technology Transfer Automated Retrieval System (TEKTRAN)

    ‘Ok102’ (Reg. no. CV-941, PI 632635) is a hard red winter wheat (Triticum aestivum L.) developed cooperatively by the Oklahoma Agric. Exp. Stn. and the USDA-ARS. Ok102 was released in March 2002, primarily on the basis of its resistance to several foliar diseases, excellent milling quality, and desi...

  2. Understanding the Genetic Interactions that Regulate Heat and Drought Tolerance in Relation to Wax Deposition and Yield Stability in Wheat (Tricticum Aestivum L.) 

    E-print Network

    Huggins, Trevis D

    2014-04-08

    Wheat (Triticum aestivum L.) has been a major food crop for nearly 8000 years. Breeders continue to face an ongoing battle to produce stress tolerant cultivars that are able to feed a rapidly increasing global population. ...

  3. QTL mapping for adult-plant resistance to stripe rust in Italian common wheat cultivars Libellula and Strampelli

    Microsoft Academic Search

    Yaming Lu; Caixia Lan; Shanshan Liang; Xiangchun Zhou; Di Liu; Gang Zhou; Qinglin Lu; Jinxue Jing; Meinan Wang; Xianchun Xia; Zhonghu He

    2009-01-01

    Italian common wheat cultivars Libellula and Strampelli, grown for over three decades in Gansu province of China, have shown\\u000a effective resistance to stripe rust. To elucidate the genetic basis of the resistance, F3 populations were developed from crosses between the two cultivars and susceptible Chinese wheat cultivar Huixianhong. The\\u000a F3 lines were evaluated for disease severity in Beijing, Gansu and

  4. Linked gene networks involved in nitrogen and carbon metabolism and levels of water-soluble carbohydrate accumulation in wheat stems

    Microsoft Academic Search

    C. Lynne McIntyre; Rosanne E. Casu; Allan Rattey; M. Fernanda Dreccer; Jason W. Kam; Anthony F. van Herwaarden; Ray Shorter; Gang Ping Xue

    High levels of water-soluble carbohydrates (WSC) provide an important source of stored assimilate for grain filling in wheat.\\u000a To better understand the interaction between carbohydrate metabolism and other metabolic processes associated with the WSC\\u000a trait, a genome-wide expression analysis was performed using eight field-grown lines from the high and low phenotypic tails\\u000a of a wheat population segregating for WSC and

  5. Reinforcement Effect of Alkali-Hydrolyzed Wheat Gluten and Shear-Degraded Wheat Starch in Carboxylated Styrene-Butadiene Composites

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Wheat gluten (WG) and wheat starch (WS) are the protein and carbohydrate obtained from wheat flours. Wheat gluten is not water soluble or dispersible due to its hydrophobic nature. To prepare wheat gluten dispersions, an alkali hydrolysis reaction was carried out to produce a stable aqueous disper...

  6. Development of trispecies backcross populations using a 2(ADD) hexaploid bridging line to introgress genes from A-genome diploids into upland cotton

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Introgression of genes from A-genome diploid Gossypium species into tetraploid upland cotton is desirable but post-zygotic breeding barriers, in addition to ploidy differences, make the task difficult. G. arboreum L. and G. herbaceum L. accessions that had been previously identified as resistant to ...

  7. 21 CFR 139.138 - Whole wheat macaroni products.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ...2014-04-01 2014-04-01 false Whole wheat macaroni products. 139.138 Section 139...Macaroni and Noodle Products § 139.138 Whole wheat macaroni products. (a) Whole wheat macaroni products are the class of food...

  8. 21 CFR 139.138 - Whole wheat macaroni products.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ...2011-04-01 2011-04-01 false Whole wheat macaroni products. 139.138 Section 139...Macaroni and Noodle Products § 139.138 Whole wheat macaroni products. (a) Whole wheat macaroni products are the class of food...

  9. 21 CFR 139.138 - Whole wheat macaroni products.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ...2013-04-01 2013-04-01 false Whole wheat macaroni products. 139.138 Section 139...Macaroni and Noodle Products § 139.138 Whole wheat macaroni products. (a) Whole wheat macaroni products are the class of food...

  10. 21 CFR 139.138 - Whole wheat macaroni products.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ...2012-04-01 2012-04-01 false Whole wheat macaroni products. 139.138 Section 139...Macaroni and Noodle Products § 139.138 Whole wheat macaroni products. (a) Whole wheat macaroni products are the class of food...

  11. Wheat Variety and Barley Malt Properties: Influence on Haze Intensity and Foam Stability of Wheat Beer

    Microsoft Academic Search

    Sofie A. Depraetere; Filip Delvaux; Stefan Coghe; Freddy R. Delvaux

    J. Inst. Brew. 110(3), 200-206, 2004 Laboratory wheat beers were brewed with different wheat va- rieties of different protein content (8.7-14.4%) and with five dif- ferent barley malts, varying in degree of modification (soluble protein: 3.9-6.9%). In a first series of experiments, it was in- vestigated whether wheat positively influences the foam stabil- ity, a major characteristic of wheat beers.

  12. Characterization of Fusarium strains recovered from wheat with symptoms of head blight in Kentucky

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Fusarium graminearum species complex (FGSC) members cause Fusarium head blight (FHB) of wheat (Triticum aestivum L.) and small grains in the United States. The U.S. population is diverse, and includes several genetically distinct local emergent subpopulations, some more aggressive and toxigenic than...

  13. Automated Single-Kernel Sorting to Select for Quality Traits in Wheat Breeding Lines

    Technology Transfer Automated Retrieval System (TEKTRAN)

    An automated single kernel near-infrared system was used to select kernels to enhance the end-use quality of hard red wheat breeder samples. Twenty breeding populations and advanced lines were sorted for hardness index, protein content, and kernel color. To determine if the phenotypic sorting was b...

  14. Aggregate stability of a silt loam soil as affected by roots of corn, soybeans and wheat

    Microsoft Academic Search

    C. D. Monroe; E. J. Kladivko

    1987-01-01

    A greenhouse experiment was conducted to investigate the effect of root growth and exudation of 3 crop species on soil aggregation. Two plant populations for each of 3 crops (corn, soybeans, and wheat) were grown in a Fincastle silt loam for 5 time periods (7, 14, 21, 28, and 41 days) and compared with fallow controls. Aggregate stability was estimated

  15. Predicting Cadmium Concentrations in Wheat and Barley Grain Using Soil Properties

    Microsoft Academic Search

    M. L. Adams; F. J. Zhao; S. P. McGrath; F. A. Nicholson; B. J. Chambers

    2004-01-01

    s the U.S. adult population was reported to receive about 20% of the FAO\\/WHO allowable daily intake of The entry of Cd into the food chain is of concern as it can cause Cd from the consumption of grain and cereal products chronic health problems. To investigate the relationship between soil properties and the concentration of Cd in wheat (Triticum

  16. SOIL ERODIBILITY AND PM10 EMISSIONS FOLLOWING TILLAGE IN A DRYLAND WHEAT-FALLOW CROPPING SYSTEM

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Traditional agronomic practices in the conventional wheat-fallow rotation employed in central Washington include multiple passes with tillage implements during the fallow cycle, both to create a dust mulch layer to retard soil moisture losses and to manage weed populations. This dust mulch, in asso...

  17. Genetic mapping analysis of bread-making quality traits in spring wheat

    Technology Transfer Automated Retrieval System (TEKTRAN)

    In this study we assess the genetic architecture of bread-making quality traits in spring wheat. A mapping population derived from BR34 and Grandin, a soft x hard cross, was used to measure 20 end-use quality traits including six kernel characteristics, seven milling and flour traits, four dough mi...

  18. Rapid Assessment of Glutenin and Gliadin in Wheat by UV Spectrophotometer

    Microsoft Academic Search

    J. Suchy; O. M. Lukow; D. Brown; R. DePauw; S. Fox; G. Humphreys

    2007-01-01

    Traditional breeding of common wheat (Triticum aestivum L.) con- centrates largely on the improvement of protein quality because of the importance of protein in end-product functionality, nutritional value, and economic impact. New, rapid, and inexpensive protein quality tests are required to identify premium quality families from large and diverse early-generation breeding populations. In this study, a simple method was designed

  19. Microsatellite tagging of the leaf rust resistance gene Lr16 on wheat chromosome 2BSc

    Microsoft Academic Search

    C. A. McCartney; D. J. Somers; B. D. McCallum; J. Thomas; D. G. Humphreys; J. G. Menzies; P. D. Brown

    2005-01-01

    Leaf rust, caused by Puccinia triticina, is one of the most damaging diseases of wheat worldwide. Lr16 is a widely deployed leaf rust resistance gene effective at the seedling stage. Although virulence to Lr16 exists in the Canadian P. triticina population, Lr16 provides a level of partial resistance in the field. The primary objective of this study was to identify

  20. Quantitative Trait Loci for Aluminum Resistance in Chinese Wheat Landrace FSW

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Aluminum (Al) toxicity is a major constraint for wheat production in acid soils worldwide. Chinese landrace FSW demonstrates a high level of Al resistance. A population of 170 F6 recombinant inbred lines (RILs) was developed from a cross between FSW and an Al-sensitive Chinese line, ND35, using sing...

  1. Grain and vegetative biomass reduction by the Russian wheat aphid in winter wheat

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The Russian wheat aphid, Diuraphis noxia (Mordvilko), is a severe pest of wheat (Triticum aestivum L.), barley (Hordeum vulgare L.), other small grains, and grasses. Although the Russian wheat aphid is a significant pest of small grains, its feeding effects on grain yield and vegetative biomass in ...

  2. Spatially discriminating Russian wheat aphid induced plant stress from other wheat stressing factors

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The Russian wheat aphid (RWA) Diuraphis noxia (Mordvilko) is a major pest of winter wheat and barley in the United States. RWA induces stress to the wheat crop by damaging plant foliage, lowering the greenness of plants, and affecting productivity. Multispectral remote sensing is effective at dete...

  3. Effects of protein in wheat flour on retrogradation of wheat starch.

    PubMed

    Xijun, Lian; Junjie, Guo; Danli, Wang; Lin, Li; Jiaran, Zhu

    2014-08-01

    Albumins, globulins, gliadins, and glutenins were isolated from wheat flour and the effects of those proteins on retrogradation of wheat starch were investigated. The results showed that only glutenins retarded retrogradation of wheat starch and other 3 proteins promoted it. The results of IR spectra proved that no S-S linkage formed during retrogradation of wheat starch blended with wheat proteins. Combination of wheat starch and globulins or gliadins through glucosidic bonds hindered the hydrolysis of wheat starch by ?-amylase. The melting peak temperatures of retrograded wheat starch attached to different proteins were 128.46, 126.14, 132.03, 121.65, and 134.84 °C for the control with no protein, albumins, glutenins, globulins, gliadins groups, respectively, and there was no second melting temperature for albumins group. Interaction of wheat proteins and starch in retrograded wheat starch greatly decreased the endothermic enthalpy (?H) of retrograded wheat starch. Retrograded wheat starch bound to gliadins might be a new kind of resistant starch based on glycosidic bond between starch and protein. PMID:25048342

  4. Partial Support for Winter Wheat Laboratory Marker-Assisted-Selection Program Phil Bruckner, Winter Wheat Breeder

    E-print Network

    Maxwell, Bruce D.

    Partial Support for Winter Wheat Laboratory Marker-Assisted-Selection Program Phil Bruckner, Winter Wheat Breeder Project Description Marker-assisted selection (MAS) is an established plant breeding with limited technological capabilities such as ours. The MSU winter wheat program conducted a laboratory MAS

  5. Wheat puroindolines interact to form friabilin and control wheat grain hardness

    Microsoft Academic Search

    A. C. Hogg; T. Sripo; B. Beecher; J. M. Martin; M. J. Giroux

    2004-01-01

    Wheat grain is sold based upon several physiochemical characteristics, one of the most important being grain texture. Grain texture in wheat directly affects many end use qualities such as milling yield, break flour yield, and starch damage. The hardness (Ha) locus located on the short arm of chromosome 5D is known to control grain hardness in wheat. This locus contains

  6. Effects of Processing on Wheat Tortilla Quality: Benefits of Hard White Wheat

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The suitability of Kansas hard white winter (HWW) wheat milled at a high extraction rate for tortilla production was investigated. Tortillas were made from eight wheat cultivars milled at 80% extraction: four HWW wheat cultivars included Betty, Heyne, Oro Blanco and NuWest; three hard red winter (H...

  7. Modification of Extensigraph Dough Preparation Method Developed for Wheat Breeding Lines and Commercial Wheat

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Dough rheological characteristics - resistance to extension and extensibility, are very important wheat flour quality traits for the milling and baking industries, and for new wheat varietal selection in wheat breeding programs. Current available techniques or test methods, such as the AACCI extens...

  8. Association Analysis of Soft Wheat Quality Traits in Eastern US Soft Winter Wheat

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Soft wheat quality is highly heritable, is controlled by multiple loci, and has been mapped in a number of bi-parental crosses. We extended the mapping information on soft wheat quality by using association analysis between genetic markers and quality phenotyping in 192 soft winter wheat cultivars ...

  9. Morphological spike diversity of Omani wheat

    Microsoft Academic Search

    S. Al Khanjari; A. A. Filatenko; K. Hammer; A. Buerkert

    2008-01-01

    Little is known about the diversity of field crops in Oman. The objective of this study therefore was to characterize wheat\\u000a accessions from this country using individual spikes collected from different wheat cultivation areas. The phenotypic assessment\\u000a of 15 qualitative and 17 quantitative characters showed variations among Omani wheat landraces. The standardized phenotypic\\u000a diversity index (H?) was with 0.66 higher

  10. Wheat Production in the Panhandle of Texas.

    E-print Network

    Whitfield, Charles J. (Charles James); Atkins, Irvin Milburn; Porter, Kenneth B.

    1952-01-01

    , Triumph and Wichita. Crop rotations, stubble mulch farming, the use of good seed, planting at the right time, proper management of graz- ing, and the control of weeds, diseases and pests in wheat, will give more stable wheat production. Wheat may... be resistant to diseases, lodging and shattering, be adapted to the harvesting methods employed, and have good milling and baking char- acteristics. Modern methods of developing new varieties consist usu- ally of crossing the best adapted commercial...

  11. Wheat breeding for end-product use

    Microsoft Academic Search

    W. Bushuk

    1998-01-01

    High grain yield is the primary objective of most wheat breeding programs around the world. In some countries, for example\\u000a Australia and Canada, a new wheat cultivar must meet a prescribed level of quality before it can be registered for commercial\\u000a production. For most traditional uses, wheat quality derives mainly from two interrelated characteristics: grain hardness\\u000a and protein content. Grain

  12. LACIE: Wheat yield models for the USSR

    NASA Technical Reports Server (NTRS)

    Sakamoto, C. M.; Leduc, S. K.

    1977-01-01

    A quantitative model determining the relationship between weather conditions and wheat yield in the U.S.S.R. was studied to provide early reliable forecasts on the size of the U.S.S.R. wheat harvest. Separate models are developed for spring wheat and for winter. Differences in yield potential and responses to stress conditions and cultural improvements necessitate models for each class.

  13. The microgeographical patterns of morphological and molecular variation of a mixed ploidy population in the species complex Actinidia chinensis.

    PubMed

    Liu, Yifei; Li, Dawei; Yan, Ling; Huang, Hongwen

    2015-01-01

    Polyploidy and hybridization are thought to have significant impacts on both the evolution and diversification of the genus Actinidia, but the structure and patterns of morphology and molecular diversity relating to ploidy variation of wild Actinidia plants remain much less understood. Here, we examine the distribution of morphological variation and ploidy levels along geographic and environmental variables of a large mixed-ploidy population of the A. chinensis species complex. We then characterize the extent of both genetic and epigenetic diversity and differentiation exhibited between individuals of different ploidy levels. Our results showed that while there are three ploidy levels in this population, hexaploids were constituted the majority (70.3%). Individuals with different ploidy levels were microgeographically structured in relation to elevation and extent of niche disturbance. The morphological characters examined revealed clear difference between diploids and hexaploids, however tetraploids exhibited intermediate forms. Both genetic and epigenetic diversity were high but the differentiation among cytotypes was weak, suggesting extensive gene flow and/or shared ancestral variation occurred in this population even across ploidy levels. Epigenetic variation was clearly correlated with changes in altitudes, a trend of continuous genetic variation and gradual increase of epigenomic heterogeneities of individuals was also observed. Our results show that complex interactions between the locally microgeographical environment, ploidy and gene flow impact A. chinensis genetic and epigenetic variation. We posit that an increase in ploidy does not broaden the species habitat range, but rather permits A. chinensis adaptation to specific niches. PMID:25658107

  14. Wheat and Barley Genome Sequencing

    Microsoft Academic Search

    Kellye Eversole; Andreas Graner; Nils Stein

    A high quality reference genome sequence is a prerequisite resource for accessing any gene, driving genomics-based approaches\\u000a to systems biology, and for efficient exploitation of natural and induced genetic diversity of an organism. Wheat and barley\\u000a possess genomes of a size that was long presumed to be not amenable for whole genome sequencing. So far, only limited genomic\\u000a sequencing of

  15. Winter wheat and summer shade

    NASA Astrophysics Data System (ADS)

    Artru, S.; Garre, S.; Lassois, L.; Dupraz, C.

    2014-12-01

    Agroforestry research is in full expansion, but uncertainty remains on the performance of combinations of species with regard to the broad range of possible species associations. In addition, the variability of environmental conditions under which agroforestry stands can be successfully developed is unknown. Under Belgian pedoclimatic conditions, tree-crop competition for light might be the principal limiting factor in the agroforestry context. Most studies show that shade stress induces a systematic reduction of final crop yield. However, the response of a specific crop to shade is highly dependent on environmental conditions. In agroforestry systems, the tree canopy reduces the incident radiation for the crop following a dynamic spatio-temporal pattern. In this study, we will report on the efficiency of wheat under artificial dynamic shade in the experimental farm of Gembloux Agro-Bio Tech, Belgium in order to evaluate it's potential for agroforestry purposes in the same region. Wheat productivity and development under artificial shade conditions have been monitored during 1 year and the observations will be continued for 2 more years. We constructed an artificial shade structure, which mimics the light environment observed under hybrid walnut agroforestry trees: periodic fluctuation in radiation transmittance and discontinuous light quantity. We collected information on biomass development, soil state and radiation patterns in the field. Using this data, we evaluated the influence of dynamic shade, light availability and the efficiency with which energy is converted in wheat dry matter under the artificial shade treatment. This, in combination with modeling, will allow a thorough study of the potential of wheat-walnut agroforestry systems in the Hesbaye region in Belgium.

  16. Structural analysis of wheat stems

    Microsoft Academic Search

    Kurt D. Hamman; Richard L. Williamson; Eric D. Steffler; Christopher T. Wright; J. Richard Hess; Peter A. Pryfogle

    2005-01-01

    Design and development of improved harvesting, preprocessing, and bulk handling systems for biomass requires knowledge of\\u000a the biomechanical properties and structural characteristics of crop residue. Structural analysis of wheat stem cross-sections\\u000a was performed using the theory of composites and finite element analysis techniques. Representative geometries of the stem’s\\u000a structural components including the hypoderm, ground tissue, and vascular bundles were established

  17. Structural Analysis of Wheat Stems

    Microsoft Academic Search

    Kurt D. Hamman; Richard L. Williamson; Eric D. Steffler; Christopher T. Wright; J. Richard Hess; Peter A. Pryfogle

    Design and development of improved harvesting, preprocessing, and bulk handling systems for biomass requires knowledge of\\u000a the biomechanical properties and structural characteristics of crop residue. Structural analysis of wheat stem cross-sections\\u000a was performed using the theory of composites and finite element analysis techniques. Representative geometries of the stem’s\\u000a structural components including the hypoderm, ground tissue, and vascular bundles were established

  18. The Role of Natural Enemy Foraging Guilds in Controlling Cereal Aphids in Michigan Wheat

    PubMed Central

    Safarzoda, Shahlo; Bahlai, Christine A.; Fox, Aaron F.; Landis, Douglas A.

    2014-01-01

    Insect natural enemies (predators and parasitoids) provide important ecosystem services by suppressing populations of insect pests in many agricultural crops. However, the role of natural enemies against cereal aphids in Michigan winter wheat (Triticum aestivum L.) is largely unknown. The objectives of this research were to characterize the natural enemy community in wheat fields and evaluate the role of different natural enemy foraging guilds (foliar-foraging versus ground-dwelling predators) in regulating cereal aphid population growth. We investigated these objectives during the spring and summer of 2012 and 2013 in four winter wheat fields on the Michigan State University campus farm in East Lansing, Michigan. We monitored and measured the impact of natural enemies by experimentally excluding or allowing their access to wheat plants infested with Rhopalosiphum padi (L.) and Sitobion avenae (F.) (Hemiptera: Aphidae). Our results indicate that the natural enemy community in the wheat fields consisted mostly of foliar-foraging and ground-dwelling predators with relatively few parasitoids. In combination, these natural enemy groups were very effective at reducing cereal aphid populations. We also investigated the role of each natural enemy foraging guild (foliar-foraging versus ground-dwelling predators) independently. Overall, our results suggest that, in combination, natural enemies can almost completely halt early-season aphid population increase. Independently, ground-dwelling predators were more effective at suppressing cereal aphid populations than foliar-foraging predators under the conditions we studied. Our results differ from studies in Europe and the US Great Plains where foliar foraging predators and parasitoids are frequently more important cereal aphid natural enemies. PMID:25473951

  19. Systems Responses to Progressive Water Stress in Durum Wheat

    PubMed Central

    Habash, Dimah Z.; Baudo, Marcela; Hindle, Matthew; Powers, Stephen J.; Defoin-Platel, Michael; Mitchell, Rowan; Saqi, Mansoor; Rawlings, Chris; Latiri, Kawther; Araus, Jose L.; Abdulkader, Ahmad; Tuberosa, Roberto; Lawlor, David W.; Nachit, Miloudi M.

    2014-01-01

    Durum wheat is susceptible to terminal drought which can greatly decrease grain yield. Breeding to improve crop yield is hampered by inadequate knowledge of how the physiological and metabolic changes caused by drought are related to gene expression. To gain better insight into mechanisms defining resistance to water stress we studied the physiological and transcriptome responses of three durum breeding lines varying for yield stability under drought. Parents of a mapping population (Lahn x Cham1) and a recombinant inbred line (RIL2219) showed lowered flag leaf relative water content, water potential and photosynthesis when subjected to controlled water stress time transient experiments over a six-day period. RIL2219 lost less water and showed constitutively higher stomatal conductance, photosynthesis, transpiration, abscisic acid content and enhanced osmotic adjustment at equivalent leaf water compared to parents, thus defining a physiological strategy for high yield stability under water stress. Parallel analysis of the flag leaf transcriptome under stress uncovered global trends of early changes in regulatory pathways, reconfiguration of primary and secondary metabolism and lowered expression of transcripts in photosynthesis in all three lines. Differences in the number of genes, magnitude and profile of their expression response were also established amongst the lines with a high number belonging to regulatory pathways. In addition, we documented a large number of genes showing constitutive differences in leaf transcript expression between the genotypes at control non-stress conditions. Principal Coordinates Analysis uncovered a high level of structure in the transcriptome response to water stress in each wheat line suggesting genome-wide co-ordination of transcription. Utilising a systems-based approach of analysing the integrated wheat’s response to water stress, in terms of biological robustness theory, the findings suggest that each durum line transcriptome responded to water stress in a genome-specific manner which contributes to an overall different strategy of resistance to water stress. PMID:25265161

  20. Wireworm management I: stand protection versus wireworm mortality with wheat seed treatments.

    PubMed

    Vernon, Robert S; van Herk, Willem G; Clodius, Markus; Harding, Chantelle

    2009-12-01

    The efficacy of various insecticidal seed treatments in protecting wheat, Triticum aestivum L., from wireworm damage as well as reducing wireworm (Coleoptera: Elateridae) populations was studied over 3 yr. Protection from wireworm damage was measured by postplanting stand counts, and effects on wireworm populations were measured by within-row core samples and by bait traps placed in plots the following spring. The effects of treatments on populations of larger wireworms already present at planting were distinguished from their effects on neonate wireworms produced that growing season. Neonicotinoid seed treatments (imidacloprid, clothianidin, and thiamethoxam) provided excellent wheat stand protection, likely through prolonged wireworm intoxication, but populations of larger and neonate wireworms were not significantly reduced in bait traps the following spring. The pyrethroid tefluthrin, applied to seed with and without a neonicotinoid insecticide (thiamethoxam), provided excellent crop protection, but populations of wireworms also were not significantly reduced. This and additional laboratory data suggest that wheat stand establishment provided by tefluthrin is due to a combination of repulsion and short term morbidity events. The phenyl pyrazole fipronil provided excellent crop protection, and populations of both larger and neonate wireworms could not be detected in plots the following spring. The previously registered organochlorine lindane, although reducing wireworm feeding, was phytotoxic in 2 of 3 yr. Next to fipronil, lindane was the most consistent seed treatment in reducing populations of larger and neonate wireworms. These studies indicate that stand and yield protection provided by contemporary wheat seed treatments cannot automatically be equated with wireworm population mortality. This is an important consideration when choosing a suitable seed treatment to replace lindane, which historically provided both stand protection and wireworm reduction, and did not have to be applied every year. PMID:20069841

  1. Search for evidence of introgression of wheat (Triticum aestivum L.) traits into sea barley (Hordeum marinum s.str. Huds.) and bearded wheatgrass (Elymus caninus L.) in central and northern Europe, using isozymes, RAPD and microsatellite markers

    Microsoft Academic Search

    R. Guadagnuolo; D. Savova-Bianchi; J. Keller-Senften; F. Felber

    2001-01-01

    Seeds of English and Austrian populations of bearded wheatgrass (Elymus caninus L.) and sea barley (Hordeum marinum Huds.) growing in the vicinity of wheat (Triticum aestivum L.) fields were collected in order to search for evidence of the introgression of wheat traits into these wild relatives.\\u000a Seeds were sown and plants grown for subsequent analyses using morphological and genetic (isozymes,

  2. Alternative Dryland Cropping Systems to Wheat Fallow

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Winter wheat-summer fallow (W-F) in the Central Great Plains of the U.S.A. is not a long-term sustainable dryland system due to a high potential for erosion and associated soil degradation. Utilizing no-till and more intensive cropping we have developed several alternative rotations to wheat fallow....

  3. WHEAT ALLERGY & INTOLERENCE; RECENT UPDATES AND PERSPECTIVES.

    PubMed

    Pasha, Imran; Saeed, Farhan; Sultan, Muhammad Tauseef; Batool, Rizwana; Aziz, Mahwash; Ahmed, Waqas

    2013-09-01

    Abstract The current review article highlights the complicacies associated with communities relying on wheat as their dietary staple. Although, wheat is an important source of nutrients but is also linked with allergenic responses in genetically susceptible subjects. The wheat proteins especially ?-amylase inhibitors, ?-5 gliadins, prolamins, non-prolamin, glucoprotein and profilins are of significance importance. The allergenic responses are further categorized into IgE-mediated and non-IgE-mediated reactions. Conjugation and degranulation of the IgEs with the allergens results in release of several mediators. In contrary, non-IgE-mediated wheat allergy depends on immune complexes formed by food and food antibodies and cell-mediated immunity. As results, different diseases tend to occur on the completion of these reactions i.e. celiac disease (CD), baker's asthma, diarrhea, atopic dermatitis (AD) and urticaria. This instant article highlighted the concept of food allergy with special reference to wheat. The models are developed that are included in this article showing the wheat allergen, their possible routes, impact on human health, and indeed possible remedies. The article would provide the basic information for the researchers, common man, and allied stakeholders to cater the issue in details. However, the issue needs the attention of the researchers as there is a need to clarify the issues of wheat allergy and wheat intolerance. PMID:24915366

  4. Wheat Leaf Rust Caused by Puccinia triticina

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Leaf rust, caused by Puccinia triticina, is the most common rust disease of wheat. The fungus is an obligate parasite capable of producing infectious urediniospores as long as the host remains healthy. Urediniospores can be wind-disseminated hundreds of kilometers and may result in wheat leaf rust e...

  5. TRACKING WHEAT RUST ON A CONTINENTAL SCALE

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The rusts of wheat are important fungal plant pathogens that can be wind disseminated for thousands of kilometers across continents and oceans. Rusts are obligate parasites that interact with resistance genes in wheat in a gene-for-gene manner. New races of rust develop by mutation and selection for...

  6. Registration of STARS 0601W wheat germplasm

    Technology Transfer Automated Retrieval System (TEKTRAN)

    STARS 0601W (PI 643399) is a hard red winter wheat (Triticum aestivum L.) germplasm developed cooperatively by the Wheat, Peanut and Other Field Crops Research Unit, USDA-Agricultural Research Service, Stillwater, Oklahoma, and the Oklahoma Agricultural Experiment Station. STARS 0601W is resistant ...

  7. SOIL-BORNE WHEAT MOSAIC VIRUS

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Soil-borne wheat mosaic virus is widely distributed in most temperate wheat growing regions of the world. It can cause significant yield loss although due to the transient symptoms that disappear as temperatures increase, the disease is often mistaken for a nutrient deficiency. The virus has many ...

  8. Sunflower phytochemicals adversely affect wheat yield.

    PubMed

    Anjum, Tehmina; Bajwa, Rukhsana

    2010-05-01

    Various researchers have reported the weedicidal potential of sunflower when used as incorporation, mulch or aqueous extract without noticing its effect on crop. This study was planned to investigate the harmful effects of sunflower phytochemicals on wheat varieties. Early laboratory experiments were performed on four wheat varieties, i.e. Inqlab-91, Punjab-96, Pasban-90 and Uqab-2000. The aqueous extract of three sunflower varieties tested against wheat varieties significantly decreased biomass of wheat seedlings, especially at concentrations of 40% and 50%. However, wheat variety Punjab-96 resisted the most, which was selected for further trials. This detrimental effect was also noticed in pot trials, the extent of which varied with the age of the wheat seedlings and number of sprays. Three early sprays with one week intervals showed maximum losses to the crop plant. The study suggests the use of sunflower extracts for the management of weeds that emerge 3-4 weeks after wheat seedlings. However, the study discourages the use of sunflower mulch or incorporation in wheat fields for weed management. PMID:20461628

  9. DIATOMACEOUS EARTH SURFACE TREATMENT FOR STORED WHEAT

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Diatomaceous earth (DE) can be used as a surface treatment in stored wheat to control pest infestations. However, it is not known how the thickness of the DE-treated wheat layer or grain temperature impacts effectiveness. When adult Rhizopertha dominica (F.), lesser grain borers, were released in e...

  10. Genetics of tan spot resistance in wheat

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Tan spot is a devastating foliar disease of wheat caused by the necrotrophic fungal pathogen Pyrenophora tritici-repentis. Much has been learned during the past two decades regarding the genetics of wheat-P. tritici-repentis interactions. Research has shown that the fungus produces at least three ho...

  11. Optimal Hedging Ratio for Pakistan's Wheat Imports

    Microsoft Academic Search

    TARIQ ALI; SARFRAZ HASSAN; KHALID MUSHTAQ; KHUDA BAKHSH

    In this paper, optimal hedging ratio is calculated for Pakistan's wheat imports from USA. Price risk faced by various market participants is estimated. Slope coefficient from OLS regression is used to calculate optimal hedging ratio (OHR). Results indicate that FOB and CIF prices of wheat are significantly volatile and need proper management of associated risk. While optimal hedging ratio of

  12. IMPACT OF OZONE ON WINTER WHEAT YIELD

    EPA Science Inventory

    Wheat is one of the more important agricultural crops in the USA, and the major production areas may be subjected to potentially damaging concentrations of ozone (O3). Since no information was available regarding the O3 sensitivity of winter wheat cultivars grown in the Midwest, ...

  13. Current status of wide hybridization in wheat

    Microsoft Academic Search

    H. C. Sharma; B. S. Gill

    1983-01-01

    Current status of wide hybridization in wheat is considered in the light of the number of hybrids produced, the number of genes transferred to commercial cultivars and their use in world wide agricuture. Some original results are presented and results of other authors are compiled to provide update information regarding wide crosses in wheat. Barriers to wide hybridization and progress

  14. Selecting wheat varieties for tortilla production

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Wheat flour tortillas are the second most consumed bread product behind white pan bread. Manufactured tortillas are formulated with highly viscoelastic hard red wheat flours selected and grown for bread making. However, the inherent properties of the bread making flours require costly reducing agent...

  15. Paint removal using wheat starch blast media

    Microsoft Academic Search

    Terry Foster; John Oestreich

    1993-01-01

    A review of the Wheat Starch Blasting technology is presented. Laboratory evaluations covering Almen Arc testing on bare 2024-T3 aluminum and magnesium, as well as crack detection on 7075-T6 bare aluminum, are discussed. Comparisons with Type V plastic media show lower residual stresses are achieved on aluminum and magnesium with wheat starch media. Dry blasting effects on the detection of

  16. Agronomic Performance of Low Phytic Acid Wheat

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Low phytic acid (LPA) genotypes of wheat are one approach to improving the nutritional quality of wheat by reducing the concentration of phytic acid in the aleurone layer, thus reducing the chelation of nutritionally important minerals and improving the bioavailability of phosphorus. Field studies ...

  17. Molecular evolution of dimeric ?-amylase inhibitor genes in wild emmer wheat and its ecological association

    PubMed Central

    2008-01-01

    Background ?-Amylase inhibitors are attractive candidates for the control of seed weevils, as these insects are highly dependent on starch as an energy source. In this study, we aimed to reveal the structure and diversity of dimeric ?-amylase inhibitor genes in wild emmer wheat from Israel and to elucidate the relationship between the emmer wheat genes and ecological factors using single nucleotide polymorphism (SNP) markers. Another objective of this study was to find out whether there were any correlations between SNPs in functional protein-coding genes and the environment. Results The influence of ecological factors on the genetic structure of dimeric ?-amylase inhibitor genes was evaluated by specific SNP markers. A total of 244 dimeric ?-amylase inhibitor genes were obtained from 13 accessions in 10 populations. Seventy-five polymorphic positions and 74 haplotypes were defined by sequence analysis. Sixteen out of the 75 SNP markers were designed to detect SNP variations in wild emmer wheat accessions from different populations in Israel. The proportion of polymorphic loci P (5%), the expected heterozygosity He, and Shannon's information index in the 16 populations were 0.887, 0.404, and 0.589, respectively. The populations of wild emmer wheat showed great diversity in gene loci both between and within populations. Based on the SNP marker data, the genetic distance of pair-wise comparisons of the 16 populations displayed a sharp genetic differentiation over long geographic distances. The values of P, He, and Shannon's information index were negatively correlated with three climatic moisture factors, whereas the same values were positively correlated by Spearman rank correlation coefficients' analysis with some of the other ecological factors. Conclusion The populations of wild emmer wheat showed a wide range of diversity in dimeric ?-amylase inhibitors, both between and within populations. We suggested that SNP markers are useful for the estimation of genetic diversity of functional genes in wild emmer wheat. These results show significant correlations between SNPs in the ?-amylase inhibitor genes and ecological factors affecting diversity. Ecological factors, singly or in combination, explained a significant proportion of the variations in the SNPs, and the SNPs could be classified into several categories as ecogeographical predictors. It was suggested that the SNPs in the ?-amylase inhibitor genes have been subjected to natural selection, and ecological factors had an important evolutionary influence on gene differentiation at specific loci. PMID:18366725

  18. Wheat quality evaluation methods to predict wheat flour tortilla production

    E-print Network

    Sullins, Barbie Denise

    1997-01-01

    of the requirements for the degree of MASTER OF SCIENCE Approved as to style and content by: R ph D. Waniska (Co- hair of Co mittee) Lloyd W. Roo (Co-Chair of Co ittee) H Imeida-Dominguez (Mem r) Ronald L. Richter (Member) Al B. W er, Jr. (Chair, Food... from Chemically-Treated Flours 143 XIV LIST OF TABLES TABLE Page Commercial Millers Providing Flour Samples 29 Chemical Treatments Given to Unbleached/Bleached Wheat Flours 30 Dough Smoothness Scores 33 IV Dough Softness Scores 33 V Dough...

  19. Short-term variability of plant populations within a regularly disturbed habitat

    Microsoft Academic Search

    L. G. Firbank

    1993-01-01

    The changing populations of weeds during 13 years of the Broadbalk continuous wheat experiment were analysed to investigate the extent of differences in shortterm variability of cover between species. The data were from two sections of the experiment where winter wheat was grown continuously under herbicide treatment for 13 and 6 years respectively. Logistic regressions were fitted to the data.

  20. Clusters of genes encoding fructan biosynthesizing enzymes in wheat and barley.

    PubMed

    Huynh, Bao-Lam; Mather, Diane E; Schreiber, Andreas W; Toubia, John; Baumann, Ute; Shoaei, Zahra; Stein, Nils; Ariyadasa, Ruvini; Stangoulis, James C R; Edwards, James; Shirley, Neil; Langridge, Peter; Fleury, Delphine

    2012-10-01

    Fructans are soluble carbohydrates with health benefits and possible roles in plant adaptation. Fructan biosynthetic genes were isolated using comparative genomics and physical mapping followed by BAC sequencing in barley. Genes encoding sucrose:sucrose 1-fructosyltransferase (1-SST), fructan:fructan 1-fructosyltransferase (1-FFT) and sucrose:fructan 6-fructosyltransferase (6-SFT) were clustered together with multiple copies of vacuolar invertase genes and a transposable element on two barley BAC. Intron-exon structures of the genes were similar. Phylogenetic analysis of the fructosyltransferases and invertases in the Poaceae showed that the fructan biosynthetic genes may have evolved from vacuolar invertases. Quantitative real-time PCR was performed using leaf RNA extracted from three wheat cultivars grown under different conditions. The 1-SST, 1-FFT and 6-SFT genes had correlated expression patterns in our wheat experiment and in existing barley transcriptome database. Single nucleotide polymorphism (SNP) markers were developed and successfully mapped to a major QTL region affecting wheat grain fructan accumulation in two independent wheat populations. The alleles controlling high- and low- fructan in parental lines were also found to be associated in fructan production in a diverse set of 128 wheat lines. To the authors' knowledge, this is the first report on the mapping and sequencing of a fructan biosynthetic gene cluster and in particular, the isolation of a novel 1-FFT gene from barley. PMID:22864927