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1.
New Phytol ; 225(2): 948-959, 2020 01.
Artigo em Inglês | MEDLINE | ID: mdl-31487050

RESUMO

Wheat stem rust, caused by Puccinia graminis Pers. f. sp. tritici (Pgt), is a devastating fungal disease threatening global wheat production. The present paper reports the identification of stem rust resistance gene Sr60, a race-specific gene from diploid wheat Triticum monococcum L. that encodes a protein with two putative kinase domains. This gene, designated as WHEAT TANDEM KINASE 2 (WTK2), confers intermediate levels of resistance to Pgt. WTK2 was identified by map-based cloning and validated by transformation of a c.10-kb genomic sequence including WTK2 into susceptible common wheat variety Fielder (Triticum aestivum L.). Transformation of Fielder with WTK2 was sufficient to confer Pgt resistance. Sr60 transcripts were transiently upregulated 1 d post-inoculation with Pgt, but not in mock-inoculated plants. The upregulation of Sr60 was associated with stable upregulation of several pathogenesis-related genes. The Sr60-resistant haplotype found in T. monococcum was not found in polyploid wheat, suggesting an opportunity to introduce a novel resistance gene. Sr60 was successfully introgressed into hexaploid wheat, and we developed a diagnostic molecular marker to accelerate its deployment and pyramiding with other resistance genes. The cloned Sr60 also can be a useful component of transgenic cassettes including other resistance genes with complementary resistance profiles.


Assuntos
Basidiomycota/fisiologia , Resistência à Doença/genética , Genes de Plantas , Doenças das Plantas/genética , Proteínas de Plantas/química , Proteínas de Plantas/genética , Triticum/genética , Mapeamento Cromossômico , Regulação da Expressão Gênica de Plantas , Haplótipos/genética , Filogenia , Poliploidia , Domínios Proteicos , RNA Mensageiro/genética , RNA Mensageiro/metabolismo
2.
Theor Appl Genet ; 131(11): 2493, 2018 11.
Artigo em Inglês | MEDLINE | ID: mdl-30310930

RESUMO

In the original publication, the IWGSC assembly is incorrectly referenced.

3.
Theor Appl Genet ; 131(3): 625-635, 2018 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-29164273

RESUMO

KEY MESSAGE: The new stem rust resistance gene Sr60 was fine-mapped to the distal region of chromosome arm 5AmS, and the TTKSK-effective gene SrTm5 could be a new allele of Sr22. The emergence and spread of new virulent races of the wheat stem rust pathogen (Puccinia graminis f. sp. tritici; Pgt), including the Ug99 race group, is a serious threat to global wheat production. In this study, we mapped and characterized two stem rust resistance genes from diploid wheat Triticum monococcum accession PI 306540. We mapped SrTm5, a previously postulated gene effective to Ug99, on chromosome arm 7AmL, completely linked to Sr22. SrTm5 displayed a different race specificity compared to Sr22 indicating that they are distinct. Sequencing of the Sr22 homolog in PI 306540 revealed a novel haplotype. Characterization of the segregating populations with Pgt race QFCSC revealed an additional resistance gene on chromosome arm 5AmS that was assigned the official name Sr60. This gene was also effective against races QTHJC and SCCSC but not against TTKSK (a Ug99 group race). Using two large mapping populations (4046 gametes), we mapped Sr60 within a 0.44 cM interval flanked by sequenced-based markers GH724575 and CJ942731. These two markers delimit a 54.6-kb region in Brachypodium distachyon chromosome 4 and a 430-kb region in the Chinese Spring reference genome. Both regions include a leucine-rich repeat protein kinase (LRRK123.1) that represents a potential candidate gene. Three CC-NBS-LRR genes were found in the colinear Brachypodium region but not in the wheat genome. We are currently developing a Bacterial Artificial Chromosome library of PI 306540 to determine which of these candidate genes are present in the T. monococcum genome and to complete the cloning of Sr60.


Assuntos
Resistência à Doença/genética , Genes de Plantas , Doenças das Plantas/genética , Triticum/genética , Basidiomycota , Mapeamento Cromossômico , Ligação Genética , Marcadores Genéticos , Haplótipos , Fenótipo , Doenças das Plantas/microbiologia , Triticum/microbiologia
4.
BMC Nurs ; 16: 58, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-29021714

RESUMO

BACKGROUND: The concept of evidence-based practice is globally relevant in current healthcare climates. However, students and teachers struggle with integrating evidence based practice effectively into a curriculum. This has implications for nurse education and in particular the way in which research is presented and delivered to students. A new undergraduate Evidence Based Practice module (Evidence Based Nursing 1) was developed in a large University within the United Kingdom. It commenced in October 2014 running in year one of a 3 year undergraduate nursing programme. This study sought to formally evaluate attitudes and beliefs, knowledge level and utilization of evidence based practice though using two validated questionnaires: Evidence Based Practice Beliefs Scale© and Evidence Based Practice Implementation Scale©. METHOD: This was a pilot study using quantitative pre and post-test design. Anonymised data was collected from Year 1 undergraduate student nurses in the September 2014 intake (n = 311) at two time points. Time 1: pre-module in September 2014; and Time 2: post -module in August 2015. All data was collected via Survey Monkey. RESULTS: Results demonstrate that the educational initiative positively impacted on both the beliefs and implementation of evidence based practice. Analysis highlighted statistically significant changes (p < 0.05) in both the Evidence Based Practice Beliefs Scale (7/16 categories) and the Evidence Based Practice Implementation Scale (13 / 18 categories). CONCLUSIONS: The significance of integrating evidence based practice into undergraduate nurse education curriculum cannot be underestimated if evidence based practice and its positive impact of patient care are to be appreciated in healthcare settings internationally.

5.
PLoS One ; 11(6): e0157029, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27309724

RESUMO

Stem rust, caused by Puccinia graminis (Pgt), is a damaging disease of wheat that can be controlled by utilizing effective stem rust resistance genes. 'Thatcher' wheat carries complex resistance to stem rust that is enhanced in the presence of the resistance gene Lr34. The purpose of this study was to examine APR in 'Thatcher' and look for genetic interactions with Lr34. A RIL population was tested for stem rust resistance in field nurseries in Canada, USA, and Kenya. BSA was used to find SNP markers associated with reduced stem rust severity. A major QTL was identified on chromosome 3BL near the centromere in all environments. Seedling testing showed that Sr12 mapped to the same region as the QTL for APR. The SNP markers were physically mapped and the region carrying the resistance was searched for sequences with homology to members of the NB-LRR resistance gene family. SNP marker from one NB-LRR-like sequence, NB-LRR3 co-segregated with Sr12. Two additional populations, including one that lacked Lr34, were tested in field nurseries. NB-LRR3 mapped near the maximum LOD for reduction in stem rust severity in both populations. Lines from a population that segregated for Sr12 and Lr34 were tested for seedling Pgt biomass and infection type, as well as APR to field stem rust which showed an interaction between the genes. We concluded that Sr12, or a gene closely linked to Sr12, was responsible for 'Thatcher'-derived APR in several environments and this resistance was enhanced in the presence of Lr34.


Assuntos
Resistência à Doença/genética , Doenças das Plantas/genética , Locos de Características Quantitativas/genética , Triticum/genética , Basidiomycota/patogenicidade , Mapeamento Cromossômico , Cromossomos de Plantas , Epistasia Genética , Genótipo , Fenótipo , Doenças das Plantas/microbiologia , Caules de Planta/crescimento & desenvolvimento , Caules de Planta/microbiologia , Polimorfismo de Nucleotídeo Único , Plântula/genética , Plântula/crescimento & desenvolvimento , Triticum/crescimento & desenvolvimento , Triticum/microbiologia
6.
Phytopathology ; 105(10): 1347-54, 2015 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-25844826

RESUMO

Race TTKSK (or Ug99) of Puccinia graminis f. sp. tritici, the causal agent of wheat stem rust, is a serious threat to wheat production worldwide. Diploid wheat, Triticum monococcum (genome Am), has been utilized previously for the introgression of stem rust resistance genes Sr21, Sr22, and Sr35. Multipathotype seedling tests of biparental populations demonstrated that T. monococcum accession PI 306540 collected in Romania contains a recessive resistance gene effective to all P. graminis f. sp. tritici races screened, including race TTKSK. We will refer to this gene as SrTm4, which is the fourth stem rust resistance gene characterized from T. monococcum. Using two mapping populations derived from crosses of PI 272557×PI 306540 and G3116×PI 306540, we mapped SrTm4 on chromosome arm 2AmL within a 2.1 cM interval flanked by sequence-tagged markers BQ461276 and DR732348, which corresponds to a 240-kb region in Brachypodium chromosome 5. The eight microsatellite and nine sequence-tagged markers linked to SrTm4 will facilitate the introgression and accelerate the deployment of SrTm4-mediated Ug99 resistance in wheat breeding programs.


Assuntos
Basidiomycota/fisiologia , Cromossomos de Plantas/genética , Resistência à Doença/genética , Doenças das Plantas/imunologia , Triticum/genética , Mapeamento Cromossômico , Diploide , Marcadores Genéticos , Genótipo , Repetições de Microssatélites/genética , Doenças das Plantas/microbiologia , Folhas de Planta/genética , Folhas de Planta/imunologia , Caules de Planta/genética , Caules de Planta/imunologia , Plântula/genética , Plântula/imunologia , Triticum/imunologia
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