Seasonal Variation of White Clover Morphology at the North of Buenos Aires Province, Argentine

In order to study the seasonal variation in morphological characters that contribute to forage production in white clover (Trifolium repens L.) cultivars, a trial was conducted at Pergamino Agricultural Experimental Station INTA located north of Buenos Aires province, Argentina. The experimental plots were set out in a completely randomized design with four replicates. Measurements were performed over eight seasons throughout two years. The used cultivars had been previously reported as having differences in seasonal productivity. Significant differences were detected among seasons for all measured characters i. e. stolon length, number of buds, branches and leaves, and leaf area. Differences among cultivars in almost all the season were only found for leaf area and stolon length. The growth in length of stolons kept a consistent pattern in both years. No cultivar produced vegetative buds during summers. The characters most affected by environmental stress were bud and branch development. Keywords: Trifolium repens L., morphological characters, seasonal variation, cultivars.Para estudiar la variación estacional de los caracteres morfológicos que contribuyen a la producción de forraje en cultivares de trébol blanco (Trifolium repens L.), se realizó un ensayo en Estación Experimental Agropecuaria Pergamino INTA ubicada al norte de la provincia de Buenos Aires, argentino Las parcelas experimentales se establecieron en un diseño completamente al azar con cuatro replica Las mediciones se realizaron durante ocho temporadas a lo largo de dos años. El usado Se había informado previamente que los cultivares tenían diferencias en la productividad estacional. Significativo se detectaron diferencias entre estaciones para todos los caracteres medidos i. mi. longitud del estolón, número de yemas, ramas y hojas, y área foliar. Diferencias entre cultivares en casi toda la temporada solo se encontraron para área foliar y longitud de estolón. El crecimiento en longitud de los estolones mantuvo un ritmo constante patrón en ambos años. Ningún cultivar produjo brotes vegetativos durante los veranos. Los personajes más afectados por el estrés ambiental fueron el desarrollo de yemas y ramas.Estación Experimental Agropecuaria PergaminoFil: Pagano, Elba M. Instituto Nacional de Tecnología Agropecuaria (INTA). Estación Experimental Agropecuaria Pergamino; ArgentinaFil: Scheneiter, Jorge Omar. Instituto Nacional de Tecnología Agropecuaria (INTA). Estación Experimental Agropecuaria Pergamino; Argentin

Características de populações naturais de Bromus cartharticus Vahl (Poaceae) coletadas na área central da Argentina

Collection of Bromus catharticus Vahl was carried out in the Argentine humid and sub-humid central area. Sixty-eight natural populations are conserved for medium and long term in Pergamino Germplasm Bank and in IRB Germplasm Bank, and ten morphological and agronomic traits were evaluated in the field during two years. There was variability for the traits considered among the accessions. Those populations from the subhumid area showed differences in valuable attributes for breeding. Exploration of marginal areas for this species might be an effective way to add variability to this collection.Coletas de Bromus catharticus Vahl foram conduzidas nas areas úmidas e sub-úmidas centrais da Argentina. Sessenta e oito populações naturais foram mantidas por médio e longo períodos nos bancos de germoplasma Pergamino e IRB, e dez características morfológicas agronômicas foram avaliadas em campo durante dois anos. Foi observada variabilidade para as características entre os acessos. As populações da região sub-úmida mostraram diferenças para características importantes para o melhoramento. A exploração de áreas marginais para esta espécie pode ser um modo efetivo de adicionar variabilidade para esta coleção de germoplasma

The genetic diversity of wild rescuegrass is associated with precipitation levels

The genus Bromus belongs to the family Poaceae, contains 3 over 160 annual and perennial species of grasses [...]Fil: Cuyeu, Romina. Instituto Nacional de Tecnología Agropecuaria. Centro Nacional de Investigaciones Agropecuarias. Centro de Investigación de Ciencias Veterinarias y Agronómicas. Instituto de Genética; ArgentinaFil: Pagano, Elba Maria. Instituto Nacional de Tecnología Agropecuaria. Centro Nacional de Investigaciones Agropecuarias. Centro de Investigación de Ciencias Veterinarias y Agronómicas. Instituto de Genética; ArgentinaFil: Rosso, Beatriz Elena. Instituto Nacional de Tecnología Agropecuaria; ArgentinaFil: Soto, Gabriela Cynthia. Consejo Nacional de Investigaciones Científicas y Técnicas. Instituto de Investigaciones en Ingeniería Genética y Biología Molecular; ArgentinaFil: Ayub, Nicolas Daniel. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Instituto Nacional de Tecnología Agropecuaria. Centro Nacional de Investigaciones Agropecuarias. Centro de Investigación de Ciencias Veterinarias y Agronómicas. Instituto de Genética; Argentin

Identificación de cultivares de trébol blanco (trifolium repens l.) mediante SSR

El trébol blanco (Trifolium repens L) es una leguminosa forrajera de gran valor nutritivo y muy eficiente en la incorporación de nitrógeno (N) al suelo mediante fijación simbiótica. En Argentina se ha difundido ampliamente en las regiones húmeda y subhúmeda. Los objetivos del presente trabajo fueron i) detectar la capacidad de marcadores moleculares microsatélites (SSR) para la diferenciación genética e identificación de cultivares de trébol blanco y ii) determinar la relación entre los agrupamientos de los cultivares basados en marcadores moleculares y caracteres agronómicos. Se analizaron 24 cultivares de trébol blanco y dos de trébol rojo de diversos orígenes. Se utilizaron 15 SSR marcados con fluorescencia. Los productos de PCR fueron separados en analizador genético ABI PRISM 3100. Se obtuvieron un total de 114 productos de amplificación, con 99 % de polimorfismo. El promedio de bandas por SSR fue de 8,66. En el dendograma obtenido de la clasificación de los 24 cultivares de trébol blanco se observó que los cultivares se distribuyen entre un 15 % y 85 % de similitud. Los cultivares de origen neozelandés fueron genéticamente los más distantes, con valores de similitud inferiores a 50 %. La correlación de matrices morfológica y genética fue significativa (r= 0,48). Los 15 cultivares de trébol blanco se clasificaron en tres grupos, que correspondieron principalmente a los tipos de trébol según el tamaño de folíolo.White clover (Trifolium repens L.) is a forage legume of high nutritive value. It is a very efficient species for nitrogen soil fixation through symbiosis. In Argentina, it has widely spread in humid and sub-humid regions. The aim of this work was to evaluate SSR molecular markers for genetic differentiation and identification of white clover cultivars. Relationships among cultivars were established and cultivars were grouped on the basis of molecular markers and morpho-agronomic characters . Twenty- four white clover cultivars and two red clover cultivars from different origins were evaluated. Fifteen SSR fluorescence markers were employed. PCR products were separated using ABI PRISM 3100 genetic analyzer. A total of 114 amplification products were obtained, with 99 % polymorphism. Average number of bands per SSR was 8.66. Cultivar similarity ranged from 15 % to 85 % , being Haifa and Zapicán the most similar. Cultivars from New Zealand were genetically more distant, with similarity values lower than 50 %. Correlation between morphological and genetic matrixes was significant (r= 0.48). All cultivars clustered in three groups, following a pattern which corresponded mainly to white clover leaflet type.EEA PergaminoFil: Randazzo, C. P. Instituto Nacional de Tecnología Agropecuaria (INTA). Instituto de Genética; ArgentinaFil: Rosso, Beatríz Susana. Instituto Nacional de Tecnología Agropecuaria (INTA). Estación Experimental Agropecuaria Pergamino. Banco de germoplasma; ArgentinaFil: Pagano, Elba Maria. Instituto Nacional de Tecnología Agropecuaria (INTA). Instituto de Genética; Argentin

Mutualism effectiveness and vertical transmission of symbiotic fungal endophytes in response to host genetic backround

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Genetic diversity in a world germplasm collection of tall fescue

Festuca arundinacea Schreb., commonly known as tall fescue, is a major forage crop in temperate regions. Recently, a molecular analysis of different accessions of a world germplasm collection of tall fescue has demonstrated that it contains different species from the genus Festuca and allowed their rapid classification into the three major morphotypes (Continental, Mediterranean and Rhizomatous). In this study, we explored the genetic diversity of 161 accessions of Festuca species from 29 countries, including 28 accessions of INTA (Argentina), by analyzing 15 polymorphic SSR markers by capillary electrophoresis. These molecular markers allowed us to detect a total of 214 alleles. The number of alleles per locus varied between 5 and 24, and the values of polymorphic information content ranged from 0.627 to 0.840. In addition, the accessions analyzed by flow cytometry showed different ploidy levels (diploid, tetraploid, hexaploid and octaploid), placing in evidence that the world germplasm collection consisted of multiple species, as previously suggested. Interestingly, almost all accessions of INTA germplasm collection were true hexaploid tall fescue, belonging to two eco-geographic races (Continental and Mediterranean). Finally, the data presented revealed an ample genetic diversity of tall fescue showing the importance of preserving the INTA collection for future breeding programs.Fil: Cuyeu, Romina. Instituto Nacional de Tecnología Agropecuaria. Centro Nacional de Investigaciones Agropecuarias. Centro de Investigación de Ciencias Veterinarias y Agronómicas. Instituto de Genética; ArgentinaFil: Rosso, Beatriz Elena. Instituto Nacional de Tecnología Agropecuaria. Centro Regional Buenos Aires Norte. Estación Experimental Agropecuaria Pergamino; ArgentinaFil: Pagano, Elba Maria. Instituto Nacional de Tecnología Agropecuaria. Centro Nacional de Investigaciones Agropecuarias. Centro de Investigación de Ciencias Veterinarias y Agronómicas. Instituto de Genética; ArgentinaFil: Soto, Gabriela Cynthia. Instituto Nacional de Tecnología Agropecuaria. Centro Nacional de Investigaciones Agropecuarias. Centro de Investigación de Ciencias Veterinarias y Agronómicas. Instituto de Genética; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Fox, Ana Romina. Consejo Nacional de Investigaciones Científicas y Técnicas. Instituto de Investigaciones en Ingeniería Genética y Biología Molecular; ArgentinaFil: Ayub, Nicolas Daniel. Instituto Nacional de Tecnología Agropecuaria. Centro Nacional de Investigaciones Agropecuarias. Centro de Investigación de Ciencias Veterinarias y Agronómicas. Instituto de Genética; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentin

Genetic diversity in a world germplasm collection of tall fescue

Festuca arundinacea Schreb., commonly known as tall fescue, is a major forage crop in temperate regions. Recently, a molecular analysis of different accessions of a world germplasm collection of tall fescue has demonstrated that it contains different species from the genus Festuca and allowed their rapid classification into the three major morphotypes (Continental, Mediterranean and Rhizomatous). In this study, we explored the genetic diversity of 161 accessions of Festuca species from 29 countries, including 28 accessions of INTA (Argentina), by analyzing 15 polymorphic SSR markers by capillary electrophoresis. These molecular markers allowed us to detect a total of 214 alleles. The number of alleles per locus varied between 5 and 24, and the values of polymorphic information content ranged from 0.627 to 0.840. In addition, the accessions analyzed by flow cytometry showed different ploidy levels (diploid, tetraploid, hexaploid and octaploid), placing in evidence that the world germplasm collection consisted of multiple species, as previously suggested. Interestingly, almost all accessions of INTA germplasm collection were true hexaploid tall fescue, belonging to two eco-geographic races (Continental and Mediterranean). Finally, the data presented revealed an ample genetic diversity of tall fescue showing the importance of preserving the INTA collection for future breeding programsFil: Cuyeu, Alba Romina. Instituto Nacional de Tecnología Agropecuaria (INTA). Instituto de Genética "Ewald A. Favret"; ArgentinaFil: Rosso, Beatriz Susana. Instituto Nacional de Tecnología Agropecuaria (INTA). Estación Experimental Agropecuaria Pergamino; ArgentinaFil: Pagano, Elba Maria. Instituto Nacional de Tecnología Agropecuaria (INTA). Instituto de Genética "Ewald A. Favret"; ArgentinaFil: Soto, Gabriela. Instituto Nacional de Tecnología Agropecuaria (INTA). Instituto de Genética "Ewald A. Favret"; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Fox, Ana Romina. Instituto Nacional de Tecnología Agropecuaria (INTA). Instituto de Genética "Ewald A. Favret"; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Ayub, Nicolás Daniel. Instituto Nacional de Tecnología Agropecuaria (INTA). Instituto de Genética "Ewald A. Favret"; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentin

Pseudomonas fluorescens Pf-5 genome-wide mutant screen for resistance to the antimicrobial peptide alfalfa snakin-1

Snakin-1, a peptide produced by higher plants, has broad-spectrum antibiotic activity, inhibiting organisms ranging from Bacteria to Eukaryotes. However, the mode of action against target organisms is poorly understood. As a first step to elucidate the mechanism, we screened a mutation library of Pseudomonas fluorescens Pf-5 in LB and agar medium supplemented with alfalfa snakin-1 (MsSN1). We identified three biofilm formation-related Pseudomonas mutants that showed increased resistance to MsSN1. Genetic, physiological and bioinformatics analysis validated the results of the mutant screens, indicating that bacterial adhesion protein lapA is probably the target of MsSN1. Collectively, these findings suggest that snakin-1 acts on microbial adhesion properties.Instituto de GenéticaFil: Ayub, Nicolás Daniel. Instituto Nacional de Tecnología Agropecuaria (INTA). Instituto de Genética; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Fox, Ana Romina. Instituto Nacional de Tecnología Agropecuaria (INTA). Instituto de Genética; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Garcia, Araceli Nora. Instituto Nacional de Tecnología Agropecuaria (INTA). Instituto de Genética; ArgentinaFil: Mozzicafreddo, Matteo. University of Camerino. School of Biosciences and Biotechnology; ItaliaFil: Cuccioloni, Massimiliano. University of Camerino. School of Biosciences and Biotechnology; ItaliaFil: Angeletti, Mauro. University of Camerino. School of Biosciences and Biotechnology; ItaliaFil: Pagano, Elba Maria. Instituto Nacional de Tecnología Agropecuaria (INTA). Instituto de Genética; ArgentinaFil: Soto, Gabriela Cinthia. Instituto Nacional de Tecnología Agropecuaria (INTA). Instituto de Genética; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentin

Alfalfa snakin-1 prevents fungal colonization and probably coevolved with rhizobia

Background: The production of antimicrobial peptides is a common defense strategy of living cells against a wide range of pathogens. Plant snakin peptides inhibit bacterial and fungal growth at extremely low concentrations. However, little is known of their molecular and ecological characteristics, including origin, evolutionary equivalence, specific functions and activity against beneficial microbes. The aim of this study was to identify and characterize snakin-1 from alfalfa (MsSN1). Results: Phylogenetic analysis showed complete congruence between snakin-1 and plant trees. The antimicrobial activity of MsSN1 against bacterial and fungal pathogens of alfalfa was demonstrated in vitro and in vivo. Transgenic alfalfa overexpressing MsSN1 showed increased antimicrobial activity against virulent fungal strains. However, MsSN1 did not affect nitrogen-fixing bacterial strains only when these had an alfalfa origin. Conclusions: The results reported here suggest that snakin peptides have important and ancestral roles in land plant innate immunity. Our data indicate a coevolutionary process, in which alfalfa exerts a selection pressure for resistance to MsSN1 on rhizobial bacteria. The increased antimicrobial activity against virulent fungal strains without altering the nitrogen-fixing symbiosis observed in MsSN1-overexpressing alfalfa transgenic plants opens the way to the production of effective legume transgenic cultivars for biotic stress resistance.Instituto de GenéticaFil: Garcia, Araceli Nora. Instituto Nacional de Tecnología Agropecuaria (INTA). Instituto de Genética; ArgentinaFil: Ayub, Nicolás Daniel. Instituto Nacional de Tecnología Agropecuaria (INTA). Instituto de Genética; ArgentinaFil: Fox, Ana Romina. Instituto Nacional de Tecnología Agropecuaria (INTA). Instituto de Genética; Argentina.Fil: Gomez, Maria Cristina. Instituto Nacional de Tecnología Agropecuaria (INTA). Instituto de Genética; ArgentinaFil: Dieguez, María José. Instituto Nacional de Tecnología Agropecuaria (INTA). Instituto de Genética; ArgentinaFil: Pagano, Elba Maria. Instituto Nacional de Tecnología Agropecuaria (INTA). Instituto de Genética; ArgentinaFil: Berini, Carolina Andrea. Instituto de Investigaciones Biomédicas en Retrovirus y SIDA; ArgentinaFil: Muschietti, Jorge Prometeo. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Departamento de Biodiversidad y Biología Experimental; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Instituto de Investigaciones en Ingeniería Genética y Biología Molecular, “Dr. Hector Torres”; ArgentinaFil: Soto, Gabriela Cinthia. Instituto Nacional de Tecnología Agropecuaria (INTA). Instituto de Genética; Argentin