28 research outputs found

    Identification of New Sources of Resistance to Wheat Stem Rust in Aegilops spp. in the Tertiary Genepool of Wheat

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    Recent stem rust epidemics in eastern Africa and elsewhere demonstrated that wheat stem rust is a re-emerging disease posing a threat to wheat production worldwide. The cultivated wheat gene pool has a narrow genetic base for resistance to virulent races, such as races in the Ug99 race group. Wild relatives of wheat are a tractable source of stem rust resistance genes. Aegilops species in the tertiary genepool have not been exploited to any great extent as a source of stem rust resistance. We evaluated 1,422 accessions of Aegilops spp. for resistance to three highly virulent races (TTKSK, TRTTF, and TTTTF) of Puccinia graminis f. sp. tritici. Species studied include Ae. biuncialis, Ae. caudata, Ae. comosa, Ae. cylindrica, Ae. geniculata, Ae. neglecta, Ae. peregrina, Ae. triuncialis, and Ae. umbellulata that do not share common genomes with cultivated wheat. High frequencies of resistance were observed as 977 (68.8%), 927 (65.2%), and 850 (59.8%) accessions exhibited low infection types to races TTKSK, TTTTF, and TRTTF, respectively. Contingency table analyses showed strong association for resistance to different races in several Aegilops spp., indicating that for a given species, the resistance genes effective against multiple races. Inheritance studies in selected accessions showed that resistance to race TTKSK is simply inherited

    Discovery and characterization of two new stem rust resistance genes in Aegilops sharonensis

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    Stem rust is one of the most important diseases of wheat in the world. When single stem rust resistance (Sr) genes are deployed in wheat, they are often rapidly overcome by the pathogen. To this end, we initiated a search for novel sources of resistance in diverse wheat relatives and identified the wild goat grass species Aegilops sharonesis (Sharon goatgrass) as a substantial reservoir of resistance to wheat stem rust. The objectives of this study were to discover and map novel Sr genes in Ae. sharonensis and to explore the possibility of identifying new Sr genes by genome-wide association study (GWAS). We developed two biparental populations between resistant and susceptible accessions of Ae. sharonensis and performed QTL and linkage analysis. In an F6 recombinant inbred line and an F2 population, two genes were identified that mapped to the short arm of chromosome 1Ssh, designated as Sr-1644-1Sh, and the long arm of chromosome 5Ssh, designated as Sr-1644-5Sh. The gene Sr-1644-1Sh confers a high level of resistance to race TTKSK (one of the Ug99 lineage races), while the gene Sr-1644-5Sh conditions strong resistance to TRTTF, another widely virulent race found in Yemen. Additionally, GWAS was conducted on 125 diverse Ae. sharonensis accessions for stem rust resistance. The gene Sr-1644-1Sh was detected by GWAS, while Sr-1644-5Sh was not detected, indicating that the effectiveness of GWAS might be affected by marker density, population structure, low allele frequency and other factors

    Association Mapping Reveals Novel Stem Rust Resistance Loci in Durum Wheat at the Seedling Stage

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    Wheat stem rust rapidly evolves new virulence to resistance genes. Recently emerged races in East Africa, such as TTKSK (or Ug99), possess broad virulence to durum cultivars, and only a limited number of genes provide resistance. An association mapping (AM) study conducted on 183 durum wheat accessions has allowed us to identify 41 quantitative trait loci (QTLs; determination coefficient [R2] values from 1.1 to 23.1%) for seedling resistance to one or more of four highly virulent stem rust races: TRTTF, TTTTF, TTKSK (Ug99), and JRCQC, two of which (TRTTF and JRCQC) were isolated from Ethiopia. Among these loci, 24 are novel, while the remaining 17 overlapped with loci previously shown to provide field resistance in Ethiopia and/or chromosome regions known to harbor designated stem rust resistance designated loci (Sr). The identified loci were either effective against multiple races or race specific, particularly for race JRCQC. Our results highlight that stem rust resistance in durum wheat is governed in part by loci for resistance across multiple races, and in part by race-specific ones (23 and 18, respectively). Collectively, these results provide useful information to improve the effectiveness of marker-assisted selection towards the release of durum wheat cultivars with durable stem rust resistance

    Modelo de estrategia de sustentabilidad, propuesta de aplicación para emprendimientos regionales en Misiones

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    Este proyecto surge en el contexto del Proyecto de investigación “Estrategias innovadoras de desarrollo regional: Emprendimientos basados en el diseño y la sustentabilidad”, de la Universidad Nacional de Misiones-Facultad de Arte y Diseño. Se busca generar modelos de estrategias proyectuales innovadoras dentro de la práctica del diseño basadas en la sustentabilidad y la refuncionalización de objetos y materiales. Desde una perspectiva global, el desarrollo sustentable de productos y servicios se ha posicionado rápidamente y es una ventaja competitiva para emprendimientos muy diversos. En nuestro país, y especialmente en Misiones, no se ha percibido aún con precisión la potencia que puede tener en la economía local la implementación de unidades económicas basadas en estrategias de esta índole. Se parte del análisis de casos preexistentes nacionales e internacionales que desarrollan estrategias de producción sustentable, especialmente aquellos que incorporan a la refuncionalización. La investigación está enfocada en casos de empresas industriales tales como: empresas que integran el sector foresto maderero (caso 1), que es uno de los de mayor potencial, tanto desde la escala industrial como desde la posibilidad de generar valor (e identidad). Y una empresa de producción de envases de papel y laminados (caso 2), se incluye porque contienen elementos diversos, además la identidad se constata en que esta empresa es la principal proveedora de material para envases de las yerbateras locales. En mencionadas empresas existen materiales de descarte, tales como: Caso 1: Despuntes de pino en diferentes estados de proceso, multilaminados y placas de terciados, descartes por problemas de producción, despuntes de los palos, y aserrín. Caso 2: Films de PP, envases de yerba, tubos de cartón, postizos plásticos de PE, tablas de madera aglomerada, pallets, entre otros. Los mencionados descartes aún no son aprovechados. Se pretende promover el desarrollo sustentable de la región y potenciar la gestión como herramienta de diseño, que ayude a articular los distintos actores que intervienen en una cadena de valor, fortaleciendo el capital humano, su cultura e identidad. El objetivo es la incubación de propuestas que sirvan como modelo para emprendedores regionales, a fin de promover y sensibilizar acerca del uso de estrategias de sustentabilidad tanto en emprendedores, como empresas e instituciones de la región, comunicando el valor económico, ambiental y social de la incorporación de procesos sustentables como variable de innovación en dichas unidades productivas.publishedVersio

    Proyecto de extensión universitaria: Manipulación de Alimentos, Educación y Seguridad Alimentaria (M.E.S.A) relevamiento bromatológico y control de alimentos en instituciones educativas y recreativas de la ciudad de La Plata

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    El objetivo de este Proyecto es el de formar Agentes Multiplicadores con criterio bromatológico que fomenten normas de control sanitario, aseguren la calidad e inocuidad de los alimentos que llegan al consumidor y apoyen la transformación, a través de Capacitación y Asistencia técnica, teniendo como punto de partida la Educación para la Salud y la Educación Ecológica.Mesa: Alimentos y Vacunas.Facultad de Ciencias Veterinaria

    Proyecto de extensión universitaria: Manipulación de Alimentos, Educación y Seguridad Alimentaria (M.E.S.A) relevamiento bromatológico y control de alimentos en instituciones educativas y recreativas de la ciudad de La Plata

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    El objetivo de este Proyecto es el de formar Agentes Multiplicadores con criterio bromatológico que fomenten normas de control sanitario, aseguren la calidad e inocuidad de los alimentos que llegan al consumidor y apoyen la transformación, a través de Capacitación y Asistencia técnica, teniendo como punto de partida la Educación para la Salud y la Educación Ecológica.Mesa: Alimentos y Vacunas.Facultad de Ciencias Veterinaria

    Proyecto de extensión universitaria: Manipulación de Alimentos, Educación y Seguridad Alimentaria (MESA) relevamiento bromatológico y control de alimentos en instituciones educativas y recreativas de la ciudad de La Plata

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    El objetivo de este Proyecto es el de formar Agentes Multiplicadores con criterio bromatológico que fomenten normas de control sanitario, aseguren la calidad e inocuidad de los alimentos que llegan al consumidor y apoyen la transformación, a través de Capacitación y Asistencia técnica, teniendo como punto de partida la Educación para la Salud y la Educación Ecológica.Mesa: Alimentos y Vacunas.Facultad de Ciencias Veterinaria

    Adaptive Radiation in Mediterranean Cistus (Cistaceae)

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    lineage consists of 12 species primarily distributed in Mediterranean habitats and is herein subject to analysis. lineages), which display asymmetric characteristics: number of species (2 vs. 10), leaf morphologies (linear vs. linear to ovate), floral characteristics (small, three-sepalled vs. small to large, three- or five-sepalled flowers) and ecological attributes (low-land vs. low-land to mountain environments). A positive phenotype-environment correlation has been detected by historical reconstructions of morphological traits (leaf shape, leaf labdanum content and leaf pubescence). Ecological evidence indicates that modifications of leaf shape and size, coupled with differences in labdanum secretion and pubescence density, appear to be related to success of new species in different Mediterranean habitats.

    Clonal chromosomal mosaicism and loss of chromosome Y in elderly men increase vulnerability for SARS-CoV-2

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    The pandemic caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2, COVID-19) had an estimated overall case fatality ratio of 1.38% (pre-vaccination), being 53% higher in males and increasing exponentially with age. Among 9578 individuals diagnosed with COVID-19 in the SCOURGE study, we found 133 cases (1.42%) with detectable clonal mosaicism for chromosome alterations (mCA) and 226 males (5.08%) with acquired loss of chromosome Y (LOY). Individuals with clonal mosaic events (mCA and/or LOY) showed a 54% increase in the risk of COVID-19 lethality. LOY is associated with transcriptomic biomarkers of immune dysfunction, pro-coagulation activity and cardiovascular risk. Interferon-induced genes involved in the initial immune response to SARS-CoV-2 are also down-regulated in LOY. Thus, mCA and LOY underlie at least part of the sex-biased severity and mortality of COVID-19 in aging patients. Given its potential therapeutic and prognostic relevance, evaluation of clonal mosaicism should be implemented as biomarker of COVID-19 severity in elderly people. Among 9578 individuals diagnosed with COVID-19 in the SCOURGE study, individuals with clonal mosaic events (clonal mosaicism for chromosome alterations and/or loss of chromosome Y) showed an increased risk of COVID-19 lethality

    Aegilops sharonensis genome-assisted identification of stem rust resistance gene Sr62

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    The wild relatives and progenitors of wheat have been widely used as sources of disease resistance (R) genes. Molecular identification and characterization of these R genes facilitates their manipulation and tracking in breeding programmes. Here, we develop a reference-quality genome assembly of the wild diploid wheat relative Aegilops sharonensis and use positional mapping, mutagenesis, RNA-Seq and transgenesis to identify the stem rust resistance gene Sr62, which has also been transferred to common wheat. This gene encodes a tandem kinase, homologues of which exist across multiple taxa in the plant kingdom. Stable Sr62 transgenic wheat lines show high levels of resistance against diverse isolates of the stem rust pathogen, highlighting the utility of Sr62 for deployment as part of a polygenic stack to maximize the durability of stem rust resistance
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