La importancia de la genotipificación profunda en el mejoramiento genético

One of the greatest challenges facing humanity is the development of sustainable strategiesto ensure food availability in response to population growth and climate change. Oneapproach that can contribute to increase food security is to close yield gaps and enhancinggenetic gain; to such end, what is known as “molecular breeding” plays a fundamental role.Since a crop breeding program is mainly based on the quality of the germplasm, its detailedgenetic characterization is mandatory to ensure the efficient use of genetic resourcesand accelerating development of superior varieties. Deep genotyping is an essential toolfor a comprehensive characterization of the germplasm of interest and, fortunately, thetechnology is now accessible at a reasonable cost. What must be ensured is the correctinterpretation of the genotypic information and on that basis develop efficient practicalmolecular crop breeding strategies that respond to the real needs of the breeding program.Uno de los mayores desafíos que enfrenta la humanidad es el desarrollo de estrategias sostenibles para asegurar la disponibilidad de alimentos en respuesta al crecimiento de la población y el cambio climático. Un enfoque que puede contribuir a aumentar la seguridad alimentaria es cerrar las brechas de rendimiento y mejorar la ganancia genética; para tal fin, lo que se conoce como “mejoramiento molecular” juega un papel fundamental. Dado que un programa de mejoramiento de cultivos se basa principalmente en la calidad del germoplasma, su caracterización genética detallada es fundamental para garantizar el uso eficiente de los recursos genéticos y acelerar el desarrollo de variedades superiores. La genotipificación profunda es una herramienta esencial para una caracterización integral del germoplasma de interés y, afortunadamente, en la actualidad se puede acceder a la tecnología a un costo razonable. Lo que debe asegurarse es la interpretación correcta de la información genotípica y sobre esa base desarrollar estrategias eficientes y prácticas de mejoramiento molecular de cultivos que respondan a las necesidades reales del programa de mejoramiento.Fil: Zambelli, Andres Daniel. Universidad Nacional de Mar del Plata. Facultad de Ciencias Agrarias; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Mar del Plata; Argentin

Effect of genetic background on the stability of sunflower fatty acid composition in different high oleic mutations

The effect of genetic background on the stability of fatty acid composition in sunflower near isogenic lines (NILs) carrying high-oleic Pervenets (P) or high-oleic NM1 mutations was studied. The materials were field-tested in different locations and at different sowing dates to evaluate a wide range of environmental conditions. Relationships were established between the fatty acids and the minimum night temperature (MNT) and the response was characterized. RESULTS: A genetic background effect for the fatty acid composition was found in both groups of NILs. The NM1-NILs showed an oleic level higher than 910 g kg−1 and they were more stable across environments with a zero or low dependence on the genetic background; on the other hand, high oleic materials bearing the P mutation showed lower levels of oleic acid, with a higher variation in fatty acid composition and a highly significant dependence on the genetic background. CONCLUSION: The NM1 mutation is the best option to develop ultra-high oleic sunflower oil that is stable across environments and genetic backgrounds, making its agronomical production more efficient and predictable.Fil: Alberio, Constanza. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Mar del Plata; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Aguirrezábal, Luis Adolfo Nazareno. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Mar del Plata; Argentina. Universidad Nacional de Mar del Plata; ArgentinaFil: Izquierdo, Natalia Gabriela. Universidad Nacional de Mar del Plata; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Mar del Plata; ArgentinaFil: Reid, Roberto. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Advanta Semillas S.A.I.C.; ArgentinaFil: Zuil, Sebastian. Universidad Nacional de Mar del Plata; ArgentinaFil: Zambelli, Andres Daniel. Universidad Nacional de Mar del Plata; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentin

Current Status of High Oleic Seed Oils in Food Processing

Dietary trans fatty acids (TFA) from industrial partial hydrogenation continue to occupy the attention of health and regulatory authorities, prompting renewed recommendations and regulations around the world. Partial hydrogenation of liquid oils was widely used because it increases the oxidative stability and plasticity of vegetable oils. The development of high oleic (HO) oils appeared as an efficient and healthy strategy to replace partially hydrogenated vegetable oils. At present, the main sources of HO oils are the HO varieties of sunflower, canola, and soybean, covering almost the entire market. Although all these HO crops show oleic acid contents higher than 70%, they can be differentiated by their fatty acid profiles. Recent clinical evidence suggests that polyunsaturated content should also be considered since its intake has been associated with coronary heart disease. Comparison of the fatty acid compositions, places HO sunflower as the best option in terms of oxidative stability and beneficial effects on the health of consumers.Fil: Zambelli, Andres Daniel. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Mar del Plata; Argentina. Universidad Nacional de Mar del Plata. Facultad de Ciencias Agrarias; Argentin

Six species of Diaporthe associated with Phomopsis stem canker of sunflower in southern Pampean region of Argentina

A survey of 67 commercial fields in 19 locations was conducted in the southern Pampean region of Argentina for Phomopsis stem canker of sunflower (Helianthus annuus L.) between 2014 and 2019. A total of 210 plants having typical symptoms of Phomopsis stem canker were randomly sampled, and fungal isolation was performed. Of the 187 isolates of Diaporthe that were recovered, 94% of the isolates showed morphological characteristics similar to D. helianthi, 3% to D. gulyae, 1% to D. caulivora, 1% to D. sojae, 0.5% to D. kongii, and 0.5% to D. longicolla. Following morphological characterization, the identity of the six morpho-species was confirmed by phylogenetic analyses of b-tubulin, translation elongation factor 1-a, and internal transcribed spacer gene regions. Koch’s postulates were completed for the six fungi by inoculating one susceptible sunflower hybrid with one isolate each of the six species of Diaporthe using the stem-wound inoculation method. Seven days postinoculation, significant differences in disease severity were observed between the six isolates (P < 0.0001), with D. helianthi and D. gulyae isolates causing significantly greater disease severity. To our knowledge, this is the first report of D. kongii, D. longicolla, D. caulivora, and D. sojae associated with Phomopsis stem canker of sunflower in Argentina.Fil: Zambelli, Andres Daniel. Universidad Nacional de Mar del Plata. Facultad de Ciencias Agrarias; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Mar del Plata; ArgentinaFil: Mancebo, María F.. Advanta Semillas S.A.I.C.; ArgentinaFil: Bazzalo, María E.. Advanta Semillas S.A.I.C.; ArgentinaFil: Reid, Roberto J.. Advanta Semillas S.A.I.C.; ArgentinaFil: Sanchez, María C.. Universidad Nacional de Mar del Plata. Facultad de Ciencias Agrarias; ArgentinaFil: Kontz, Brian J.. South Dakota State University; Estados UnidosFil: Mathew, Febina M.. South Dakota State University; Estados Unido

Differential behavior to drought of two elite potato cultivars grown in southeastern pampean region of Argentina

Potatoes production requires large inputs of water for which development of drought tolerant cultivars is particularly relevant to ensure or even increase its productivity. Two elite cultivars, Newen INTA and Spunta, were evaluated in the field under contrasting water regimes. After drought treatment, the yield of marketable tubers decreased 53% in Spunta and 22% in Newen INTA while the number of marketable tubers decreased 32% in both cultivars. Yield of tuber > 90 mm only decreased in Spunta (62.81%, p < 0.05). Newen INTA showed a greater reduction in the shoot and root dry biomass than Spunta, while the root/shoot ratio was higher in Newen INTA. Proline content increased 61% in both cultivars under drought treatment. Drought tolerance indices (GMP and DTI) were higher in Newen INTA, and the drought susceptibility index was higher in Spunta. Proline content was correlated with root dry biomass and the marketable tuber number in both cultivars. Dry root biomass correlated with the yield of marketable tubers and the number of marketabletubers. In drought conditions, Newen INTA showed greater tolerance to drought. Therefore, Newen INTA emerges as a useful genotype to contribute to increasing crop productivity in areas subject to water stress.Fil: Tagliotti, Martin Enrique. Instituto Nacional de Tecnología Agropecuaria. Centro Regional Buenos Aires Sur. Estación Experimental Agropecuaria Balcarce; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Giuliano, Sergio. Universidad Nacional de Mar del Plata. Facultad de Ciencias Agrarias; ArgentinaFil: Puricelli, Marino Marcelo. Instituto Nacional de Tecnología Agropecuaria. Centro Regional Buenos Aires Sur. Estación Experimental Agropecuaria Balcarce; ArgentinaFil: Zambelli, Andres Daniel. Universidad Nacional de Mar del Plata. Facultad de Ciencias Agrarias; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Bedogni, María Cecilia. Instituto Nacional de Tecnología Agropecuaria. Centro Regional Buenos Aires Sur. Estación Experimental Agropecuaria Balcarce; Argentin

Temperature effect on triacylglycerol species in seed oil from high stearic sunflower lines with different genetic backgrounds

BACKGROUND: This study characterized the influence of temperature during grain filling on the saturated fatty acid distribution in triacylglycerol molecules from high stearic sunflower lines with different genetic backgrounds. Two growth chamber experiments were conducted with day/night temperatures of 16/16, 26/16, 26/26 and 32/26 °C.Fil: Izquierdo, Natalia Gabriela. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Universidad Nacional de Mar del Plata. Facultad de Ciencias Agrarias. Cátedra de Fisiología Vegetal; Argentina. Instituto Nacional de Tecnología Agropecuaria. Centro Regional Buenos Aires Sur. Estación Experimental Agropecuaria Balcarce; ArgentinaFil: Martínez Force, Enrique. Consejo Superior de Investigaciones Científicas; EspañaFil: Garcés, Rafael. Consejo Superior de Investigaciones Científicas; EspañaFil: Aguirrezábal, Luis Adolfo Nazareno. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Universidad Nacional de Mar del Plata. Facultad de Ciencias Agrarias. Cátedra de Fisiología Vegetal; Argentina. Instituto Nacional de Tecnología Agropecuaria. Centro Regional Buenos Aires Sur. Estación Experimental Agropecuaria Balcarce; ArgentinaFil: Zambelli, Andres Daniel. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Centro de Investigaciones Biotecnológicas; ArgentinaFil: Reid, Roberto. Centro de Investigaciones Biotecnológicas; Argentin

A new sunflower high oleic mutation confers stable oil grain fatty acid composition across environments

The oil industry demands sunflower oils with high oleic acid content. New varieties producing high oleic oils independently of the growing environment are needed as growers could receive an extra prime for offering them. Oil fatty acid composition of high oleic sunflower hybrids currently available carrying the Pervenets mutation could however be affected by the temperature during the grain filling period. A new high oleic mutation has been obtained to attain oils with ultra-high oleic levels (>90%oleic acid content). This new structural mutation would be able to reduce the variation in oleic acid percentage to changes in the minimum night temperature (MNT). The aim of this work was to assess the response of oil fatty acid composition of the new high oleic mutation to MNT compared to traditional and Pervenets genotypes. Field experiments in different sowing dates and locations and one growth chambers experiment were performed to explore a wide range of temperatures (11.8-23.2°C) during grain filling. The oleic acid percentage in traditional and high oleic Pervenets genotypes varied between 15.0-50.9% and 87.4-91.2%, respectively, while the new mutation genotype presented values of oleic acid between 91.3 and 92.5%. Moreover, the oleic acid percentage of traditional and Pervenets genotypes showed a linear and positive response to temperature (slopes 2.95 and 0.28%oleic acid °C-1, respectively). No response to temperature was detected in the new mutation genotype. The ultra-high oleic quality from the new high oleic sunflower mutant could be obtained in a wide range of environments as the fatty acid composition was not affected by temperature during grain filling, representing an advantage over the high oleic Pervenets and traditional genotypes.Fil: Alberio, Constanza. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Universidad Nacional de Mar del Plata; ArgentinaFil: Izquierdo, Natalia Gabriela. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Universidad Nacional de Mar del Plata; ArgentinaFil: Galella, Teresa. Advanta Semillas S.A.I.C.; ArgentinaFil: Zuil, Sebastian. Instituto Nacional de Tecnología Agropecuaria. Centro Regional Santa Fe. Estación Experimental Agropecuaria Reconquista; ArgentinaFil: Reid, Roberto. Advanta Semillas S.A.I.C.; ArgentinaFil: Zambelli, Andres Daniel. Advanta Semillas S.A.I.C.; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Aguirrezábal, Luis Adolfo Nazareno. Universidad Nacional de Mar del Plata; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentin

Theory of orthogonal interactions of CO molecules on a one-dimensional substrate

A minimal model based on density-functional theory is proposed and solved to explain the unusual chemisorption properties of carbon-monooxide (CO) molecules on Cu(110)-(2 × 1)-O quasi-one-dimensional (1D) surface reported in Feng. The striking features of CO adsorption include (1) the strong lifting of the host Cu atom by 1 Å, and (2) the highly anisotropic CO-CO interaction leading to self-assembly into a nanograting structure. Our model implies that the 1D nature of the surface band is the key to these two features. We illustrate how formation of a chemical bond through specific orbital interactions between an adsorbate and 1D dispersive states of the substrate can impact the surface geometrical and electronic structure. © 2012 American Physical Society.We thank DOE-BES Division of Chemical Sciences, Geosciences, and Biosciences for support through Grant No. DE-FG02-09ER16056, W. M. Keck foundation, Ministerio de Ciencia e Innovación (Grant No. FIS2010-19609-C02-00) and G.V.-UPV/EHU (Grant No. IT-366-07) for financial support.Peer Reviewe