6 research outputs found
Sunflower Hybrid Breeding: From Markers to Genomic Selection
In sunflower, molecular markers for simple traits as, e.g., fertility restoration, high oleic acid content, herbicide tolerance or resistances to Plasmopara halstedii, Puccinia helianthi, or Orobanche cumana have been successfully used in marker-assisted breeding programs for years. However, agronomically important complex quantitative traits like yield, heterosis, drought tolerance, oil content or selection for disease resistance, e.g., against Sclerotinia sclerotiorum have been challenging and will require genome-wide approaches. Plant genetic resources for sunflower are being collected and conserved worldwide that represent valuable resources to study complex traits. Sunflower association panels provide the basis for genome-wide association studies, overcoming disadvantages of biparental populations. Advances in technologies and the availability of the sunflower genome sequence made novel approaches on the whole genome level possible. Genotype-by-sequencing, and whole genome sequencing based on next generation sequencing technologies facilitated the production of large amounts of SNP markers for high density maps as well as SNP arrays and allowed genome-wide association studies and genomic selection in sunflower. Genome wide or candidate gene based association studies have been performed for traits like branching, flowering time, resistance to Sclerotinia head and stalk rot. First steps in genomic selection with regard to hybrid performance and hybrid oil content have shown that genomic selection can successfully address complex quantitative traits in sunflower and will help to speed up sunflower breeding programs in the future. To make sunflower more competitive toward other oil crops higher levels of resistance against pathogens and better yield performance are required. In addition, optimizing plant architecture toward a more complex growth type for higher plant densities has the potential to considerably increase yields per hectare. Integrative approaches combining omic technologies (genomics, transcriptomics, proteomics, metabolomics and phenomics) using bioinformatic tools will facilitate the identification of target genes and markers for complex traits and will give a better insight into the mechanisms behind the traits
Una nueva temporalidad: progreso individual, progreso instantáneo
Partiendo del análisis de un grupo de publicidades de tecnologías informáticas aparecidas en el diario Clarín en los primeros años de la aparición de Internet en Argentina se busca dar cuenta de algunas de las transformaciones Que ha sufrido la idea moderna de progreso. Al ser atravesada por diversos aspectos de un contexto posmoderno, la idea de futuro y por tanto de progreso aparece como modificada básica- mente en dos aspectos: en primer lugar una reducción de las dimensiones sociales de la idea de progreso, Que ahora adopta características claramente individuales y abandona cualquier aspiración a un progreso de la sociedad como con- junto; en segundo lugar la idea misma de futuro aparece cercenada en sus miras de largo plazo. Muelles metáforas del camino a recorrer Que durante la modernidad sirvieron para representar el concepto de progreso, como el lugar donde arribar luego de un largo trayecto, parecen ahora adoptar la nueva forma del acceso o el ingreso . Así, no se arribaría al futuro conjuntamente luego de recorrer un extenso camino, sino Que al futuro se ingresaría individual e instantánea- mente contando con la llave o las claves individualmente obtenidas, apareciendo como amenazante la siempre presente posibilidad de Quedar excluido del futuro
Management of Field-Evolved Resistance to Bt Maize in Argentina: A Multi-Institutional Approach
Evolution of resistance to control measures in insect populations is a natural process, and management practices are intended to delay or mitigate resistance when it occurs. During the 2012/13 season the first reports of unexpected damage by Diatraea saccharalis on some Bt maize hybrids occurred in the northeast of San Luis province, Argentina. The affected Bt technologies were Herculex I® (HX-TC1507) and VT3PRO® (MON 89034 × MON 88017*). Event TC1507 expresses Cry1F and event MON 89034 expresses Cry1A.105 and Cry2Ab2, whichr are all Bt proteins with activity against the lepidopterans D. saccharalis and Spodoptera frugiperda (MON 88017 expresses the protein Cry3Bb1 for control of coleopteran insects and the enzyme CP4EPSPS for glyphosate tolerance). The affected area is an isolated region surrounded by sierra systems to the northeast and west, with a hot semi-arid climate, long frost-free period, warm winters, hot dry summers, and woody shrubs as native flora. To manage and mitigate the development of resistance, joint actions were taken by the industry, growers and Governmental Agencies. Hybrids expressing Vip3A protein (event MIR162) and/or Cry1Ab protein (events MON 810 and Bt11) as single or stacked events are used in early plantings to control the first generations of D. saccharalis, and in later plantings date's technologies with good control of S. frugiperda. A commitment was made to plant the refuge, and pest damage is monitored. As a result, maize production in the area is sustainable and profitable with yields above the average