Um método rápido para fenotipagem da resistência à imazamox em trigo

The availability of imidazolinone (IMI) resistant cultivars has provided an effective option for weed control in wheat production systems. IMI herbicides control several weeds, including Avena fatua and Lolium multiflorum that are the most frequent grass weeds in wheat crops of Argentine Pampas. The aim of this study was to develop a soil-less method that allows a rapid phenotyping of IMI resistance in wheat. Nine wheat cultivars differing in IMI resistance were evaluated through a between-paper germination method. Herbicide concentrations required to reduce shoot and root length by 50% for resistant cultivars were > 75-fold that of the susceptible cultivars. The response of resistant and susceptible commercial cultivars was assessed in the between-paper and a top-paper methods at 100 µM imazamox as discriminating dose. The Z´-factor was calculated for evaluation of the quality of the screening methods. Both germination methods showed Z´-factors > 0 indicating that the assays were appropriate but the between-paper method allowed to save space in the growth chamber. The germination methods were useful for distinguishing between susceptible and resistant plants carrying at least one resistance gene. The rapid, simple and cost-effective method described in the present study could be a potential tool when selecting for IMI resistance in wheat in breeding programs.A disponibilidade de cultivares resistentes à imidazolinona (IMI) proporcionou uma opção eficaz para o controle de plantas daninhas em sistemas de produção de trigo. Os herbicidas IMI controlam várias plantas daninhas, incluindo Avena fatua e Lolium multiflorum, as gramíneas mais frequentes nas culturas de trigo nos Pampas argentinos. O objetivo deste trabalho foi desenvolver um método sem solo que permita a fenotipagem rápida de resistência ao IMI em trigo. Avaliaram-se nove cultivares de trigo, diferentes na resistência ao IMI, por meio de um método de germinação entre folhas de papel. As concentrações de herbicidas necessárias para reduzir o comprimento da parte aérea e da raiz em 50% para cultivares resistentes foram > 75 vezes que as dos cultivares suscetíveis. A resposta de cultivares comerciais resistentes e suscetíveis, avaliada nos métodos entre folhas de papel e papel, foi superior a 100 mM de imazamox como dose discriminante. O fator Z’ foi calculado para a avaliação da qualidade dos métodos de triagem. Ambos os métodos de germinação mostraram Z’-fatores > 0, indicando que foram apropriados, porém o método entre folhas de papel permitiu economizar espaço na câmara de crescimento. Os testes de germinação foram úteis para distinguir entre plantas suscetíveis e resistentes portadoras de pelo menos um gene de resistência. O método rápido, simples e econômico descrito no presente estudo pode ser uma ferramenta importante para selecionar trigo resistente ao IMI em programas de melhoramento.Fil: Breccia, Gabriela. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Rosario. Instituto de Investigaciones en Ciencias Agrarias de Rosario. Universidad Nacional de Rosario. Facultad de Ciencias Agrarias. Instituto de Investigaciones en Ciencias Agrarias de Rosario; ArgentinaFil: Bisio, María Belén. Universidad Nacional de Rosario. Facultad de Ciencias Agrarias. Departamento de Biología. Cátedra de Genética; ArgentinaFil: Picardi, Liliana Amelia. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Rosario. Instituto de Investigaciones en Ciencias Agrarias de Rosario. Universidad Nacional de Rosario. Facultad de Ciencias Agrarias. Instituto de Investigaciones en Ciencias Agrarias de Rosario; ArgentinaFil: Nestares, Graciela María. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Rosario. Instituto de Investigaciones en Ciencias Agrarias de Rosario. Universidad Nacional de Rosario. Facultad de Ciencias Agrarias. Instituto de Investigaciones en Ciencias Agrarias de Rosario; Argentina. Universidad Nacional de Rosario. Facultad de Ciencias Agrarias. Departamento de Biología. Cátedra de Genética; Argentin

Precision phenotyping of imidazolinone-induced chlorosis in sunflower

Chlorosis level is a useful parameter to assess imidazolinone resistance in sunflower (Helianthus annuus L.). The aim of this study was to quantify chlorosis through two different methods in sunflower plantlets treated with imazapyr. The genotypes used in this study were two inbred lines reported to be different in their resistance to imidazolinones. Chlorosis was evaluated by spectrophotometrical quantification of photosynthetic leaf pigments and by a bioinformatics-based color analysis. A protocol for pigment extraction was presented which improved pigment stability. Chlorophyll amount decreased significantly when both genotypes were treated with 10 μM of imazapyr. Leaf color was characterized using Tomato Analyzer® color test software. A significant positive correlation between color reduction and chlorophyll concentration was found. It suggests that leaf color measurement could be an accurate method to estimate chlorosis and infer chlorophyll levels in sunflower plants. These results highlight a strong relationship between imidazolinone-induced chlorosis and variations in leaf color and in chlorophyll concentration. Both methods are quantitative, rapid, simple, and reproducible. Thus, they could be useful tools for phenotyping and screening large number of plants when breeding for imidazolinone resistance in this species.Fil: Ochogavía, Ana Claudia. Universidad Nacional de Rosario. Facultad de Ciencias Agrarias. Laboratorio de Biología Molecular; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Rosario; ArgentinaFil: Gil, Mercedes. Universidad Nacional de Rosario. Facultad de Ciencias Agrarias. Departamento de Biología. Cátedra de Genética; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Rosario; ArgentinaFil: Picardi, Liliana Amelia. Universidad Nacional de Rosario. Facultad de Ciencias Agrarias. Departamento de Biología. Cátedra de Genética; Argentina. Universidad Nacional de Rosario. Consejo de Investigaciones de la Universidad de Rosario; ArgentinaFil: Nestares, Graciela María. Universidad Nacional de Rosario. Facultad de Ciencias Agrarias. Departamento de Biología. Cátedra de Genética; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Rosario; Argentin

Proteomics of the tomato ripening : identification of two fruit ripening stages by total pericarp protein profiles in tomato RILs

Durante la madurez del fruto se producen cambios morfológicos, fisiológicos y bioquímicos provocados por la expresión regulada de diferentes genes. El objetivo de este trabajo fue verificar si la presencia de polipéptidos totales del pericarpio en los estados verde maduro (VM) y rojo maduro (RM) permite caracterizar la madurez del tomate. Se analizaron 18 líneas endocriadas recombinantes obtenidas por selección antagónica-divergente de un cruzamiento entre la cv. Caimanta (Solanum lycopersicum) y la entrada LA722 (S. pimpinellifolium), que fueron incluidas junto a la F1 como testigos experimentales. Los extractos proteicos se obtuvieron de dos muestras independientes de cada estado según el protocolo estándar y se resolvieron en SDS-PAGE. Se analizó la presencia/ausencia de bandas por genotipos y por estado, detectándose 26 en VM y 29 en RM. Algunas bandas fueron comunes entre estados, mientras que otras resultaron propias de VM o RM, respectivamente. Se calcularon las distancias de Jaccard y se realizó un análisis de conglomerados según el método UPGMA. En el dendrograma (correlación cofenética = 0,43) se distinguieron dos grandes grupos definidos por el estado de madurez. Se concluye que los perfiles proteicos del pericarpio son una herramienta postgenómica apropiada para identificar dos estados de madurez del fruto de tomate.Several morphological, physiological, and biochemical changes are produced by the regulated expression of different genes during fruit ripening. The aim of this investigation was to check the ability of total polypeptides profiles of the pericarp tissue at the mature-green (VM) and red-ripe (RM) stages for characterizing tomato fruit ripening. Eighteen recombinant inbred lines obtained by antagonic-divergent selection from a cross between cv. Caimanta of Solanum lycopersicum and accession LA722 of S. pimpinellifolium (included with the F1 as experimental testers) were analyzed. Protein extracts were collected from two independent samples from each stage following the standard protocol and solved in SDS-PAGE. The presence/absence of polypeptides by genotypes and by stage was analyzed. Twenty-six polypeptides were detected in VM and 29 in RM. Some of them were common to both stages, while others were stage-specific (either in VM or in RM). Jaccard distances among stages were calculated and a conglomates analysis was carried by UPGMA method. In the dendrogram (cophenetic correlation = 0.43) two well defined groups were distinguished by the ripening stage. As a conclusion, protein profiles of the pericarp are a postgenomic tool appropriate for identifying two ripening stages of the tomato fruit.Fil: Gallo, Mariana. Universidad Nacional de RosarioFil: Rodríguez, Gustavo. Universidad Nacional de RosarioFil: Zorzoli, Roxana. Universidad Nacional de RosarioFil: Picardi, Liliana Amelia. Universidad Nacional de RosarioFil: Pratta, Guillermo Raúl. Universidad Nacional de Rosari

Caracterización de la generación segregante de un híbrido de tomate con genes nor y silvestres

The objective of this work was to study recombination of the productive and fruit quality traits in the segregating generation of the hybrid between a cultivated variety ofLycopersicon esculentum homozygous for nor and the accession LA1385 of L. esculentum var. cerasiforme using multivariate statistical analysis. F1and F2 generations and the parents were evaluated for vegetative and productive traits (internode length, stem perimeter at the basal, middle and apical parts, number of flowers per cluster, number of clusters per plant and days to harvest) and quality fruit traits (weight, shape, soluble solids content, acidity, firmness, color and shelf life). A canonical correlation between vegetative and productive traits and those of fruit quality and clustering for fruit traits performed with the F1 and F2 and the parents were used. The productive and fruit quality traits showed recombination in the segregating generation. Shelf life was the most outstanding fruit trait to discriminate groups in the F2. For three cluster levels each group of F2individuals behaved each one of the parents and the F1.The objective of this work was to study recombination of the productive and fruit quality traits in the segregating generation of the hybrid between a cultivated variety of Lycopersicon esculentum homozygous for nor and the accession LA1385 of L. esculentum var. cerasiforme using multivariate statistical analysis. F1 and F2 generations and the parents were evaluated for vegetative and productive traits (internode length, stem perimeter at the basal, middle and apical parts, number of flowers per cluster, number of clusters per plant and days to harvest) and quality fruit traits (weight, shape, soluble solids content, acidity, firmness, color and shelf life). A canonical correlation between vegetative and productive traits and those of fruit quality and clustering for fruit traits performed with the F1 and F2 and the parents were used. The productive and fruit quality traits showed recombination in the segregating generation. Shelf life was the most outstanding fruit trait to discriminate groups in the F2. For three cluster levels each group of F2 individuals behaved each one of the parents and the F1.El objetivo del trabajo fue estudiar en la generación segregante del híbrido entre una cultivar de Lycopersicon esculentum homocigota para el gen nor y la accesión LA1385 de L. esculentum var. cerasiforme, la recombinación de caracteres productivos y de calidad de fruto a través de las metodologías de análisis multivariado. En las generaciones F1 y F2 y en los progenitores se evaluaron caracteres vegetativos y productivos (longitud de entrenudos, perímetro del tallo en las partes basal, media y apical, número de flores por inflorescencia, número de inflorescencias por planta y días a cosecha) y de calidad de fruto (peso, forma, sólidos solubles, acidez, firmeza, color y vida poscosecha). Se utilizaron las correlaciones canónicas entre los caracteres vegetativos y productivos y los de calidad de fruto y también un análisis de agrupamiento para las características del fruto, incluyendo los progenitores, la F1 y la F2. Estos análisis permitieron demostrar que las características productivas y de calidad de fruto recombinaron en la generación segregante. La vida poscosecha fue la característica de los frutos más importante para discriminar grupos en la F2. Para tres niveles de agrupamiento cada grupo de individuos F2 se comportó como alguno de los progenitores o la F1

Contribution of non-target-site resistance in imidazolinone-resistant imisun sunflower

The first commercial herbicide-resistant trait in sunflower (Helianthus annuus L.) is known as ‘Imisun’. Imidazolinone resistance in Imisun cultivars has been reported to be genetically controlled by a major gene (known as Imr1 or Ahasl1-1) and modifier genes. Imr1 is an allelic variant of the Ahasl1 locus that codes for the acetohydroxyacid synthase, which is the target site of these herbicides. The mechanism of resistance endowed by modifier genes has not been characterized and it could be related to non-target-site resistance. The objective of this study was to evaluate the role of cytochrome P450 monooxygenases (P450s) in Imisun resistance. The response to imazapyr herbicide in combination with P450s inhibitor malathion was evaluated in 2 Imisun lines, IMI-1 and RHA426. Malathion reduced herbicide efficacy in both lines, but IMI-1 was affected in a greater extent. A significant reduction in plant growth in response to P450s inhibitors 1-aminobenzotriazole and piperonyl butoxide treatment was detected in the Imisun line HA425. The increased susceptibility to imazapyr after P450s-inhibitor treatment indicates that herbicide metabolism by P450s is a mechanism involved in Imisun resistance. These results also suggest the involvement of different P450s isozymes in endowing resistance to imazapyr in Imisun cultivars.Fil: Breccia, Gabriela. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Rosario. Instituto de Investigaciones en Ciencias Agrarias de Rosario. Universidad Nacional de Rosario. Facultad de Ciencias Agrarias. Instituto de Investigaciones en Ciencias Agrarias de Rosario; ArgentinaFil: Gil, Mercedes. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Rosario. Instituto de Investigaciones en Ciencias Agrarias de Rosario. Universidad Nacional de Rosario. Facultad de Ciencias Agrarias. Instituto de Investigaciones en Ciencias Agrarias de Rosario; ArgentinaFil: Vega, Tatiana Alejandra. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Rosario. Instituto de Investigaciones en Ciencias Agrarias de Rosario. Universidad Nacional de Rosario. Facultad de Ciencias Agrarias. Instituto de Investigaciones en Ciencias Agrarias de Rosario; ArgentinaFil: Altieri, Emiliano. Nidera S. A. Departamento de Biotecnología; ArgentinaFil: Bulos, Mariano. Nidera S. A. Departamento de Biotecnología; ArgentinaFil: Picardi, Liliana Amelia. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Rosario. Instituto de Investigaciones en Ciencias Agrarias de Rosario. Universidad Nacional de Rosario. Facultad de Ciencias Agrarias. Instituto de Investigaciones en Ciencias Agrarias de Rosario; ArgentinaFil: Nestares, Graciela María. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Rosario. Instituto de Investigaciones en Ciencias Agrarias de Rosario. Universidad Nacional de Rosario. Facultad de Ciencias Agrarias. Instituto de Investigaciones en Ciencias Agrarias de Rosario; Argentin

Assessment of the carcass traits of lambs with ¾ of the Texel breed genotype

Thirty six ¾ Texel (T) and 32 Ideal lambs were grown in feedlot for two months postweaning to evaluate final liveweight (FLW), relative average daily gain (ADGr) and various carcass characteristics, including: cold carcass weight (CCW), total lean weight (TLW), loin weight (LW), and total fat weight (TFW). Differences were found between males of the two genotypes in FW (P<.01) and TLW (P<.05); and between the females in TFW (P<.05). There were no differences between genotypes in ADGr. A multiple regression analysis relating FLW, as dependent variable, and the carcass variables as independent, showed that 73% of the variation in liveweight of the¾T animals was associated withLW and TLW. At conclusion of the confinement feeding, blood plasma samples from three lambs of each genotype/sex were analyzed for relative proportions of the mayor fatty acids and concentrations of total cholesterol and triglycerides. A negative relationship was found between the proportion of oleic acid and degree of fatness, expressed as (TFW/CCW) (100), whereas for linoleic acid the relationship was positive

Factores genéticos que afectan la calidad del fruto del tomate

La calidad de los frutos en tomate juega un rol muy importante tanto en la elección de los cultivares por parte de los productores como en la demanda del producto obtenido por parte de los consumidores. Un carácter relacionado a la calidad de fundamental importancia y altamente apreciado para la comercialización del fruto fresco, es la prolongación de su vida poscosecha. La biotecnología ha hecho considerables progresos para modificar vías metabólicas involucradas en la madurez del fruto.Trabajo galardonado con el Premio Fundación Pérez Companc, versión 2010Academia Nacional de Agronomía y Veterinari

Factores genéticos que afectan la calidad del fruto del tomate

La calidad de los frutos en tomate juega un rol muy importante tanto en la elección de los cultivares por parte de los productores como en la demanda del producto obtenido por parte de los consumidores. Un carácter relacionado a la calidad de fundamental importancia y altamente apreciado para la comercialización del fruto fresco, es la prolongación de su vida poscosecha. La biotecnología ha hecho considerables progresos para modificar vías metabólicas involucradas en la madurez del fruto.Trabajo galardonado con el Premio Fundación Pérez Companc, versión 2010Academia Nacional de Agronomía y Veterinari

Panel: Planeamiento y metodología de los cursos de postgrado

Resúmenes de los trabajos presentados en el panel y síntesis.Academia Nacional de Agronomía y Veterinaria (ANAV