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Sunflower Verticillium Wilt and Leaf Mottle (SVW), caused by Verticillium dahliae (Kleb.; Vd), is a soil-borne disease affecting sunflower worldwide. A single dominant locus, known as V1, was formerly effective in controlling North-American Vd races, whereas races from Argentina, Europe and an emerging race from USA overcome its resistance. This emphasizes the need for identifying broad-spectrum genetic resistance (BSR) sources. Here we characterize two sunflower mapping populations (MPs) for SVW resistance: a biparental MP and the association MP from the National Institute of Agricultural Technology (INTA), under field growing conditions. Nine field-trials (FTs) were conducted in highly infested fields in the most SVW-affected region of Argentina. Several disease descriptors (DDs), including incidence and severity, were scored across four phenological stages. Generalized linear models were fitted according to the nature of each variable, adjusting mean phenotypes for inbred lines across and within FTs. Comparison of these responses allowed the identification of novel BSR sources. Furthermore, we present the first report of SVW resistance heritability, with estimates ranging from 35 to 45% for DDs related to disease incidence and severity, respectively. This study constitutes the largest SVW resistance characterization reported to date in sunflower, identifying valuable genetic resources for BSR-breeding to cope with a pathogen of increasing importance worldwide. EEA Pergamino Fil: Montecchia, Juan Francisco. Instituto Nacional de Tecnología Agropecuaria (INTA). Instituto de Biotecnología. Consejo Nacional de Investigaciones Científicas y Técnicas. Instituto de Agrobiotecnología y Biología Molecular (IABIMO); Argentina Fil: Fass, Mónica I. Instituto Nacional de Tecnología Agropecuaria (INTA). Instituto de Biotecnología. Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET). Instituto de Agrobiotecnología y Biología Molecular (IABIMO); Argentina Fil: Cerrudo, Ignacio. Instituto Nacional de Tecnología Agropecuaria (INTA). Estación Experimental Agropecuaria Balcarce; Argentina Fil: Quiroz, Facundo José. Instituto Nacional de Tecnología Agropecuaria (INTA). Estación Experimental Agropecuaria Balcarce; Argentina Fil: Nicosia, Salvador Maria. Instituto Nacional de Tecnología Agropecuaria (INTA). Instituto de Biotecnologoía. Consejo Nacional de Investigaciones Científicas y Técnicas. Instituto de Agrobiotecnología y Biología Molecular (IABIMO); Argentina Fil: Maringolo, Carla Andrea. Instituto Nacional de Tecnología Agropecuaria (INTA). Estación Experimental Agropecuaria Balcarce; Argentina Fil: Di Rienzo, Julio. Universidad Nacional de Córdoba. Facultad de Ciencias Agropecuarias; Argentina Fil: Troglia, Carolina Beatriz. Instituto Nacional de Tecnología Agropecuaria (INTA). Estación Experimental Agropecuaria Balcarce; Argentina Fil: Hopp, Horacio Esteban. Instituto Nacional de Tecnología Agropecuaria (INTA). Instituto de Biotecnologoía. Consejo Nacional de Investigaciones Científicas y Técnicas. Instituto de Agrobiotecnología y Biología Molecular (IABIMO); Argentina Fil: Hopp, Horacio Esteban. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales; Argentina Fil: Escande, Alberto. Instituto Nacional de Tecnología Agropecuaria (INTA). Estación Experimental Agropecuaria Balcarce; Argentina Fil: Gonzalez, Julio Horacio. Instituto Nacional de Tecnología Agropecuaria (INTA). Estación Experimental Agropecuaria Pergamino. Sección Girasol; Argentina Fil: Alvarez, Daniel. Instituto Nacional de Tecnología Agropecuaria (INTA). Estación Experimental Agropecuaria Manfredi; Argentina Fil: Heinz, Ruth Amelia. Instituto Nacional de Tecnología Agropecuaria (INTA). Instituto de Biotecnologoía. Consejo Nacional de Investigaciones Científicas y Técnicas. Instituto de Agrobiotecnología y Biología Molecular (IABIMO); Argentina Fil: Lia, Veronica Viviana. Instituto Nacional de Tecnología Agropecuaria (INTA). Instituto de Biotecnologoía. Consejo Nacional de Investigaciones Científicas y Técnicas. Instituto de Agrobiotecnología y Biología Molecular (IABIMO); Argentina Fil: Lia, Veronica Viviana. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales; Argentina Fil: Paniego, Norma Beatriz. Instituto Nacional de Tecnología Agropecuaria (INTA). Instituto de Biotecnologoía. Consejo Nacional de Investigaciones Científicas y Técnicas. Instituto de Agrobiotecnología y Biología Molecular (IABIMO); Argentina

Background: Sclerotinia sclerotiorum is a necrotrophic fungus that causes Sclerotinia head rot (SHR) in sunflower, with epidemics leading to severe yield losses. In this work, we present an association mapping (AM) approach to investigate the genetic basis of natural resistance to SHR in cultivated sunflower, the fourth most widely grown oilseed crop in the world. Results: Our association mapping population (AMP), which comprises 135 inbred breeding lines (ILs), was genotyped using 27 candidate genes, a panel of 9 Simple Sequence Repeat (SSR) markers previously associated with SHR resistance via bi-parental mapping, and a set of 384 SNPs located in genes with molecular functions related to stress responses. Moreover, given the complexity of the trait, we evaluated four disease descriptors (i.e, disease incidence, disease severity, area under the disease progress curve for disease incidence, and incubation period). As a result, this work constitutes the most exhaustive AM study of disease resistance in sunflower performed to date. Mixed linear models accounting for population structure and kinship relatedness were used for the statistical analysis of phenotype-genotype associations, allowing the identification of 13 markers associated with disease reduction. The number of favourable alleles was negatively correlated to disease incidence, disease severity and area under the disease progress curve for disease incidence, whereas it was positevily correlated to the incubation period. Conclusions: Four of the markers identified here as associated with SHR resistance (HA1848, HaCOI_1, G33 and G34) validate previous research, while other four novel markers (SNP117, SNP136, SNP44, SNP128) were consistently associated with SHR resistance, emerging as promising candidates for marker-assisted breeding. From the germplasm point of view, the five ILs carrying the largest combination of resistance alleles provide a valuable resource for sunflower breeding programs worldwide. Fil: Filippi, Carla Valeria. Instituto Nacional de Tecnología Agropecuaria. Centro de Investigación en Ciencias Veterinarias y Agronómicas. Instituto de Agrobiotecnología y Biología Molecular. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Parque Centenario. Instituto de Agrobiotecnología y Biología Molecular; Argentina Fil: Zubrzycki, Jeremías Enrique. Instituto Nacional de Tecnología Agropecuaria. Centro de Investigación en Ciencias Veterinarias y Agronómicas. Instituto de Agrobiotecnología y Biología Molecular. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Parque Centenario. Instituto de Agrobiotecnología y Biología Molecular; Argentina Fil: Di Rienzo, Julio Alejandro. Universidad Nacional de Córdoba. Facultad de Ciencias Agropecuarias; Argentina Fil: Quiroz, Facundo José. Instituto Nacional de Tecnología Agropecuaria. Centro Regional Buenos Aires Sur. Estación Experimental Agropecuaria Balcarce; Argentina Fil: Puebla, Andrea Fabiana. Instituto Nacional de Tecnología Agropecuaria. Centro de Investigación en Ciencias Veterinarias y Agronómicas. Instituto de Agrobiotecnología y Biología Molecular. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Parque Centenario. Instituto de Agrobiotecnología y Biología Molecular; Argentina Fil: Alvarez, D.. Instituto Nacional de Tecnología Agropecuaria. Centro Regional Córdoba. Estación Experimental Agropecuaria Manfredi; Argentina Fil: Maringolo, C. A.. Instituto Nacional de Tecnología Agropecuaria. Centro Regional Buenos Aires Sur. Estación Experimental Agropecuaria Balcarce; Argentina Fil: Escande, Alberto Raul. Instituto Nacional de Tecnología Agropecuaria. Centro Regional Buenos Aires Sur. Estación Experimental Agropecuaria Balcarce; Argentina Fil: Hopp, Horacio Esteban. Instituto Nacional de Tecnología Agropecuaria. Centro de Investigación en Ciencias Veterinarias y Agronómicas. Instituto de Agrobiotecnología y Biología Molecular. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Parque Centenario. Instituto de Agrobiotecnología y Biología Molecular; Argentina Fil: Heinz, Ruth Amelia. Instituto Nacional de Tecnología Agropecuaria. Centro de Investigación en Ciencias Veterinarias y Agronómicas. Instituto de Agrobiotecnología y Biología Molecular. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Parque Centenario. Instituto de Agrobiotecnología y Biología Molecular; Argentina Fil: Paniego, Norma Beatriz. Instituto Nacional de Tecnología Agropecuaria. Centro de Investigación en Ciencias Veterinarias y Agronómicas. Instituto de Agrobiotecnología y Biología Molecular. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Parque Centenario. Instituto de Agrobiotecnología y Biología Molecular; Argentina Fil: Lia, Veronica Viviana. Instituto Nacional de Tecnología Agropecuaria. Centro de Investigación en Ciencias Veterinarias y Agronómicas. Instituto de Agrobiotecnología y Biología Molecular. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Parque Centenario. Instituto de Agrobiotecnología y Biología Molecular; Argentina

The Asteraceae family is the largest and most diversified family of the Angiosperms, characterized by the presence of numerous clustered inflorescences, which have the appearance of a single compound flower. It is estimated that this family represents around 10% of all flowered species, with a great biodiversity, covering all environments on the planet, except Antarctica. Also, it includes economically important crops, such as lettuce, sunflower, and chrysanthemum; wild flowers; herbs, and several species that produce molecules with pharmacological properties. Nevertheless, the biotechnological improvement of this family is limited to a few species and their genetic transformation was achieved later than in other plant families. Lettuce (Lactuca sativa L.) is a model species in molecular biology and plant biotechnology that has easily adapted to tissue culture, with efficient shoot regeneration from different tissues, organs, cells, and protoplasts. Due to this plasticity, it was possible to obtain transgenic plants tolerant to biotic or abiotic stresses as well as for the production of commercially interesting molecules (molecular farming). These advances, together with the complete sequencing of lettuce genome allowed the rapid adoption of gene editing using the CRISPR system. On the other hand, sunflower (Helianthus annuus L.) is a species that for years was considered recalcitrant to in vitro culture. Although this difficulty was overcome and some publications were made on sunflower genetic transformation, until now there is no transgenic variety commercialized or authorized for cultivation. In this article, we review similarities (such as avoiding the utilization of the CaMV35S promoter in transformation vectors) and differences (such as transformation efficiency) in the state of the art of genetic transformation techniques performed in these two species. Instituto de Biotecnología Fil: Darqui, Flavia Soledad. Instituto Nacional de Tecnología Agropecuaria (INTA). Instituto de Agrobiotecnología y Biología Molecular; Argentina Fil: Darqui, Flavia Soledad. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina Fil: Radonic, Laura Mabel. Instituto Nacional de Tecnología Agropecuaria (INTA). Instituto de Agrobiotecnología y Biología Molecular; Argentina Fil: Radonic, Laura Mabel. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina Fil: Beracochea, Valeria Cecilia. Instituto Nacional de Tecnología Agropecuaria (INTA). Instituto de Agrobiotecnología y Biología Molecular; Argentina Fil: Beracochea, Valeria Cecilia. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina Fil: Hopp, Horacio Esteban. Instituto Nacional de Tecnología Agropecuaria (INTA). Instituto de Agrobiotecnología y Biología Molecular; Argentina Fil: Hopp, Horacio Esteban. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Fil: Hopp, Horacio Esteban. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Departamento de Fisiología, Biología Molecular y Celular; Argentina Fil: Lopez Bilbao, Marisa Gisela. Instituto Nacional de Tecnología Agropecuaria (INTA). Instituto de Agrobiotecnología y Biología Molecular; Argentina. Fil: Lopez Bilbao, Marisa Gisela. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina

Plasmopara halstedii (Farl.) Berl. & De Toni causing downy mildew of sunflower is responsible for considerable economic losses worldwide. Because P. halstedii can be seed-transmitted, monitoring of seeds for pathogen contamination is important for the sunflower seed trade. The relevance of asymptomatic or latent infections as factors of disease spread have not been studied by molecular techniques. A molecular marker based on a putative effector gene of P. halstedii was used to examine the pathogen´s presence in asymptomatic sunflowers growing near patches of mildewed plants in naturally infected fields. The method based on conventional PCR was highly sensitive for detection of P. halstedii in DNA from whole seeds. By the application of this protocol, we found that all seed samples obtained from symptomatic plants amplified the expected fragment, whereas the diagnostic marker identified the presence of pathogen in one out of 21 asymptomatic plants. Possible uses of this marker to detect downy mildew in seed from asymptomatic plants or for race identification are discussed. Fil: Martínez, Ana Laura. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Bahía Blanca. Centro de Recursos Naturales Renovables de la Zona Semiárida. Universidad Nacional del Sur. Centro de Recursos Naturales Renovables de la Zona Semiárida; Argentina Fil: Quiroz, Facundo José. Instituto Nacional de Tecnología Agropecuaria. Centro Regional Buenos Aires Sur. Estación Experimental Agropecuaria Balcarce. Agencia de Extensión Rural Balcarce; Argentina Fil: Carrera, Alicia Delia. Universidad Nacional del Sur. Departamento de Agronomía; Argentina

The aims of the present study were to assess the phenotypic diversity among 221 sunflower accessions of INTA Pergamino Sunflower Breeding Program, to obtain discriminant functions that allow the classification of new accessions in similar groups and to evaluate the relationship between genetic distance pairwise accessions and hybrid performance for grain yield and oil content. We used 19 quantitative descriptors to evaluate phenotypic and morphological variability. Principal Component Analysis (PCA) and Hierarchical Cluster Analysis (HCA) were used to evaluate simultaneously all the variables and to describe phenotypic variation patterns of the germplasm. The distribution of germplasm in the dendrogram did not follow a clear pattern with regard to the predefined groups. This study revealed the variability observed among the lines that form the INTA Pergamino breeding program despite the highly selective forces applied to obtain inbred lines that produce superior hybrids for the Argentinean sunflower area. This work demonstrates the need for more in-depth study of genetic variability to be used as a predictor of heterosis in sunflower. EEA Pergamino Fil: Dominguez, Matías. Instituto Nacional de Tecnología Agropecuaria (INTA). Estación Experimental Agropecuaria Pergamino. Sección Girasol; Argentina Fil: Dominguez, Matías. Consejo Nacional de Investigaciones Científicas y Tecnicas; Argentina Fil: Herrera, Stefanía. Universidad Nacional del Noroeste de Buenos Aires; Argentina Fil: Gonzalez, Julio Horacio. Instituto Nacional de Tecnología Agropecuaria (INTA). Estación Experimental Agropecuaria Pergamino. Sección Girasol; Argentina

Sclerotinia head rot (SHR) is one of the most serious constraints to sunflower (Helianthus annuus L. var. macrocarpus) production worldwide. Here, we evaluated the response to SHR in a sunflower inbred panel from a large INTA germplasm collection, consisting of 137 inbred lines (ILs). Field trials were performed over five consecutive seasons using a twice-replicated randomized complete-block design. Disease incidence, disease severity, incubation period and area under disease progress curve for disease incidence and severity were determined after controlled inoculation with the pathogen. Statistical analysis using mixed-effect models detected significant differences among ILs for all variables (P

Background: Leaf senescence is a complex process, controlled by multiple genetic and environmental variables. In sunflower, leaf senescence is triggered abruptly following anthesis thereby limiting the capacity of plants to keep their green leaf area during grain filling, which subsequently has a strong impact on crop yield. Recently, we performed a selection of contrasting sunflower inbred lines for the progress of leaf senescence through a physiological, cytological and molecular approach. Here we present a large scale transcriptomic analysis using RNA-seq and its integration with metabolic profiles for two contrasting sunflower inbred lines, R453 and B481-6 (early and delayed senescence respectively), with the aim of identifying metabolic pathways associated to leaf senescence. Results: Gene expression profiles revealed a higher number of differentially expressed genes, as well as, higher expression levels in R453, providing evidence for early activation of the senescence program in this line. Metabolic pathways associated with sugars and nutrient recycling were differentially regulated between the lines. Additionally, we identified transcription factors acting as hubs in the co-expression networks; some previously reported as senescence-associated genes in model species but many are novel candidate genes. Conclusions: Understanding the onset and the progress of the senescence process in crops and the identification of these new candidate genes will likely prove highly useful for different management strategies to mitigate the impact of senescence on crop yield. Functional characterization of candidate genes will help to develop molecular tools for biotechnological applications in breeding crop yield. Fil: Moschen, Sebastián Nicolás. Instituto Nacional de Tecnología Agropecuaria. Centro Regional Tucuman-Santiago del Estero. Estación Experimental Agropecuaria Famaillá; Argentina. Instituto Nacional de Tecnología Agropecuaria. Centro de Investigación en Ciencias Veterinarias y Agronómicas. Instituto de Agrobiotecnología y Biología Molecular. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Parque Centenario. Instituto de Agrobiotecnología y Biología Molecular; Argentina Fil: Marino, Johanna Magali. Universidad Nacional de San Martín; Argentina Fil: Nicosia, Salvador. Instituto Nacional de Tecnología Agropecuaria. Centro de Investigación en Ciencias Veterinarias y Agronómicas. Instituto de Agrobiotecnología y Biología Molecular. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Parque Centenario. Instituto de Agrobiotecnología y Biología Molecular; Argentina Fil: Higgins, Janet. Earlham Institute; Reino Unido Fil: Alseekh, Saleh. No especifíca; Fil: Astigueta, Francisco Horacio. Instituto Nacional de Tecnología Agropecuaria. Centro de Investigación en Ciencias Veterinarias y Agronómicas. Instituto de Agrobiotecnología y Biología Molecular. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Parque Centenario. Instituto de Agrobiotecnología y Biología Molecular; Argentina Fil: Bengoa Luoni, Sofia Ailin. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata. Instituto de Investigaciones Biotecnológicas. Instituto de Investigaciones Biotecnológicas "Dr. Raúl Alfonsín" (sede Chascomús). Universidad Nacional de San Martín. Instituto de Investigaciones Biotecnológicas. Instituto de Investigaciones Biotecnológicas "Dr. Raúl Alfonsín" (sede Chascomús); Argentina Fil: Rivarola, Maximo Lisandro. Instituto Nacional de Tecnología Agropecuaria. Centro de Investigación en Ciencias Veterinarias y Agronómicas. Instituto de Agrobiotecnología y Biología Molecular. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Parque Centenario. Instituto de Agrobiotecnología y Biología Molecular; Argentina Fil: Fernie, Alisdair R.. No especifíca; Fil: Blanchet, Nicolas. Centre National de la Recherche Scientifique; Francia Fil: Langlade, Nicolas B.. Centre National de la Recherche Scientifique; Francia Fil: Paniego, Norma Beatriz. Instituto Nacional de Tecnología Agropecuaria. Centro de Investigación en Ciencias Veterinarias y Agronómicas. Instituto de Agrobiotecnología y Biología Molecular. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Parque Centenario. Instituto de Agrobiotecnología y Biología Molecular; Argentina Fil: Fernández, Paula. No especifíca; Fil: Heinz, Ruth Amelia. Instituto Nacional de Tecnología Agropecuaria. Centro de Investigación en Ciencias Veterinarias y Agronómicas. Instituto de Agrobiotecnología y Biología Molecular. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Parque Centenario. Instituto de Agrobiotecnología y Biología Molecular; Argentina

Transgenic wheat expressing the sunflower transcription factor HaHB4 outyields the wild type by 6% when tested in the field during 9 years across 37 contrasting environments., HaHB4 is a sunflower transcription factor belonging to the homeodomain-leucine zipper I family whose ectopic expression in Arabidopsis triggers drought tolerance. The use of PCR to clone the HaHB4 coding sequence for wheat transformation caused unprogrammed mutations producing subtle differences in its activation ability in yeast. Transgenic wheat plants carrying a mutated version of HaHB4 were tested in 37 field experiments. A selected transgenic line yielded 6% more (P

Gene flow can have several different applied consequences, ranging from extinction to the escape of transgenes to the evolution of weedy or invasive lineages. Here, we describe patterns of hybridization and gene flow involving domesticated and wild sunflowers in Argentina. To address the risks of introgression of variants from the cultivated sunflower into invasive wild Helianthus, we used genotyping‐by‐sequencing (GBS) to genotype 182 samples from 11 sites in Argentina, along with previously published data from samples from the native range (North America), to determine the native source populations of the Argentinian samples and to detect admixture. We unexpectedly discovered two distinctive forms of H. petiolaris in Argentina, one from H. petiolaris subsp. petiolaris as expected, but the other from an unknown source. Extensive admixture was observed among Argentinian sunflowers, largely confirming phenotypic predictions. While many hybrids are F1s, there were signals consistent with introgression from the domesticated sunflower into H. petiolaris. Whether this introgression is incidental or a causal driver of invasiveness is not yet clear, but it seems likely that genes found in the domesticated sunflower genome (whether engineered or not) will quickly find their way into wild Argentinian sunflower populations. EEA Hilario Ascasubi Fil: Mondon, Ana Laura. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Bahía Blanca. Centro de Recursos Naturales Renovables de la Zona Semiárida; Argentina Fil: Owens, Gregory L. University of British Columbia. Department of Botany and Biodiversity Research Centre; Canada Fil: Poverene, Maria Monica. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Bahía Blanca. Centro de Recursos Naturales Renovables de la Zona Semiárida; Argentina. Universidad Nacional del Sur. Departamento de Agronomía; Argentina Fil: Cantamutto, Miguel Angel. Instituto Nacional de Tecnología Agropecuaria (INTA). Estación Experimental Agropecuaria Hilario Ascasubi; Argentina Fil: Rieseberg, Loren H. University of British Columbia. Department of Botany and Biodiversity Research Centre; Canada

Leaf senescence is a complex process controlled by multiple genetic and environmental variables. In different crops, a delay in leaf senescence has an important impact on grain yield trough the maintenance of the photosynthetic leaf area during the reproductive stage. In sunflower (Helianthus annuus L.), the fourth largest oil crop worldwide, senes‐ cence reduces the capacity of plants to maintain their green leaf area for longer periods, especially during the grain filling phase, leading to important economic losses. In crop species, taking into account the temporal gap between the onset and the phe‐ notypic detection of senescence, identification of both, candidate genes and functional stay-green are indispensable to enable the early detection of senescence, the elucida‐ tion of molecular mechanisms and the development of tools for breeding applications. In this chapter a comprehensive literature revision of leaf senescence process not only in model plant species but also in agronomical relevant crops is presented. Results derived from system biology approaches integrating transcriptomic, metabolomic and physiological data as well as those leading to the selection and characterization of stay green sunflower genotypes are included, making an important contribution to the knowledge of leaf senescence process and providing a valuable tool to assist in crop breeding. Fil: Moschen, Sebastián Nicolás. Instituto Nacional de Tecnología Agropecuaria. Centro de Investigación en Ciencias Veterinarias y Agronómicas. Instituto de Biotecnología; Argentina. Universidad Nacional de San Martín. Escuela de Ciencia y Tecnología; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina Fil: López, Agustín Ignacio. Instituto Nacional de Tecnología Agropecuaria. Centro de Investigación en Ciencias Veterinarias y Agronómicas. Instituto de Biotecnología; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina Fil: Paniego, Norma Beatriz. Instituto Nacional de Tecnología Agropecuaria. Centro de Investigación en Ciencias Veterinarias y Agronómicas. Instituto de Biotecnología; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina Fil: Fernández, Paula del Carmen. Instituto Nacional de Tecnología Agropecuaria. Centro de Investigación en Ciencias Veterinarias y Agronómicas. Instituto de Biotecnología; Argentina. Universidad Nacional de San Martín. Escuela de Ciencia y Tecnología; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina Fil: Heinz, Ruth Amelia. Instituto Nacional de Tecnología Agropecuaria. Centro de Investigación en Ciencias Veterinarias y Agronómicas. Instituto de Biotecnología; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina

Sunflower (Helianthus annuus) is one of the main oleaginous crops in the world and Argentina is positioned among the top sunflower seed producers worldwide (FAO, 2019). During the 2018-2019 crop season, sunflower plants showing symptoms similar to those reported for the tobacco streak virus (TSV) were observed in one field of Rivera, Buenos Aires province. The symptoms included leaf mosaic, severe necrosis of stem, petioles, leaves and pith, often progressing to complete collapse and death of affected plants (e-Xtra). Samples from symptomatic leaf tissue were collected from five plants and leaves of sunflower seedlings maintained under greenhouse conditions were used as healthy control. Leaf extracts obtained from symptomatic leaves were positive by DAS-ELISA test, using a polyclonal antibody against TSV (Bioreba, Switzerland). The average optical density of infected samples was 0.384, eight times higher than the mean plus three standard deviations of four healthy controls. Total RNA was extracted from collected samples using RNeasy Plant Mini Kit (Qiagen, Hilden, Germany) and tested by reverse transcription-polymerase chain reaction (RT-PCR) with specific TSV primers (Almeida et al., 2005). Only infected samples produced expected amplicons (~1 kb). The RT-PCR products, obtained in duplicate from two symptomatic plants were purified and sequenced in both directions. The sequences were generated by individually sequencing and assembling each product to avoid assemble possible variants. The obtained sequences were assembled using the DNASTAR Lasergene SeqMan software (DNASTAR, Madison, WI) and generated a consensus 969 bp sequence, which included the gene of the 714 nt CP and a 255 nt 3? untranslated region. The obtained sequences were identical, then a single nucleotide sequence was deposited in GenBank database under the accession number MK732934, and used in the analysis. A BLASTn analysis of the obtained sequence with those available in the GenBank database showed the highest nucleotide sequence identity (91%, 78-100% query coverage) with TSV isolates from Australia (JX463336, EU871659, EU375481). Phylogenetic trees obtained by using Bayesian inference in Mr. Bayes 3.2.6 (Ronquist et al. 2012) indicated that the TSV isolate from Argentina clustered together with those from Australia (JX463336, EU871659, EU375481) and Brazil (AY354406) (e-Xtra). TSV has been associated with disease epidemics in sunflower and a range of legume and vegetable crops worldwide (Gracia and Feldman, 1974; Sharman et al. 2009; Bag et al. 2019). To our knowledge, this is the first report of the occurrence of TSV infecting sunflower crops in Argentina. According to Sharman et al. (2016), the use of tolerant germplasm is critical to minimise the risk of TSV epidemics in sunflower. This finding should be addressed in future studies of resistant-cultivars selection in Argentina. Fil: Cabrera Mederos, Dariel. Instituto Nacional de Tecnología Agropecuaria; Argentina. Instituto Nacional de Tecnologia Agropecuaria. Centro de Investigaciones Agropecuarias. Unidad de Fitopatologia y Modelizacion Agricola. - Consejo Nacional de Investigaciones Cientificas y Tecnicas. Centro Cientifico Tecnologico Conicet - Cordoba. Unidad de Fitopatologia y Modelizacion Agricola.; Argentina Fil: Trucco, Verónica Milagros. Instituto Nacional de Tecnología Agropecuaria; Argentina Fil: Bejerman, Nicolas. Instituto Nacional de Tecnologia Agropecuaria. Centro de Investigaciones Agropecuarias. Unidad de Fitopatologia y Modelizacion Agricola. - Consejo Nacional de Investigaciones Cientificas y Tecnicas. Centro Cientifico Tecnologico Conicet - Cordoba. Unidad de Fitopatologia y Modelizacion Agricola.; Argentina Fil: Lenardon, Sergio Luis. Instituto Nacional de Tecnología Agropecuaria; Argentina Fil: Giolitti, Fabián José. Instituto Nacional de Tecnología Agropecuaria; Argentina

Background In recent years, high throughput technologies have led to an increase of datasets from omics disciplines allowing the understanding of the complex regulatory networks associated with biological processes. Leaf senescence is a complex mechanism controlled by multiple genetic and environmental variables, which has a strong impact on crop yield. Transcription factors (TFs) are key proteins in the regulation of gene expression, regulating different signaling pathways; their function is crucial for triggering and/or regulating different aspects of the leaf senescence process. The study of TF interactions and their integration with metabolic profiles under different developmental conditions, especially for a non-model organism such as sunflower, will open new insights into the details of gene regulation of leaf senescence. Results Weighted Gene Correlation Network Analysis (WGCNA) and BioSignature Discoverer (BioSD, Gnosis Data Analysis, Heraklion, Greece) were used to integrate transcriptomic and metabolomic data. WGCNA allowed the detection of 10 metabolites and 13 TFs whereas BioSD allowed the detection of 1 metabolite and 6 TFs as potential biomarkers. The comparative analysis demonstrated that three transcription factors were detected through both methodologies, highlighting them as potentially robust biomarkers associated with leaf senescence in sunflower. Conclusions The complementary use of network and BioSignature Discoverer analysis of transcriptomic and metabolomic data provided a useful tool for identifying candidate genes and metabolites which may have a role during the triggering and development of the leaf senescence process. The WGCNA tool allowed us to design and test a hypothetical network in order to infer relationships across selected transcription factor and metabolite candidate biomarkers involved in leaf senescence, whereas BioSignature Discoverer selected transcripts and metabolites which discriminate between different ages of sunflower plants. The methodology presented here would help to elucidate and predict novel networks and potential biomarkers of leaf senescence in sunflower. Electronic supplementary material The online version of this article (doi:10.1186/s12859-016-1045-2) contains supplementary material, which is available to authorized users.

Se evaluó la sustitución de grasa animal por grasa vegetal en un producto escaldado utilizando la carne de búfalo en un salchichón seleccionado por su aceptabilidad en Colombia. Las formulaciones experimentales fueron preparadas por triplicado utilizando aceite de soya, cañóla y girasol en 5%, 10% y 15%, estas fueron comparadas frente a un patrón, en el cual se utilizo carnes de vacuno y grasa animal. La humedad, proteína, grasa y textura (Warner-Bratzler) fueron determinadas por duplicado. La aceptabilidad fue evaluada con panel sensorial no entrenado. Los datos experimentales fueron evaluados mediante estadística descriptiva con análisis vahanza multivahado y univahado, y establecieron que no hubo diferencias significativas entre las diferentes formulaciones con soya y girasol. El análisis sensorial definió como mejor producto el salchichón resultante del aceite de soya al 10%.

Leaf senescence is a complex process, which has dramatic consequences on crop yield. In sunflower, gap between potential and actual yields reveals the economic impact of senescence. Indeed, sunflower plants are incapable of maintaining their green leaf area over sustained periods. This study characterizes the leaf senescence process in sunflower through a systems biology approach integrating transcriptomic and metabolomic analyses: plants being grown under both glasshouse and field conditions. Our results revealed a correspondence between profile changes detected at the molecular, biochemical and physiological level throughout the progression of leaf senescence measured at different plant developmental stages. Early metabolic changes were detected prior to anthesis and before the onset of the first senescence symptoms, with more pronounced changes observed when physiological and molecular variables were assessed under field conditions. During leaf development, photosynthetic activity and cell growth processes decreased, whereas sucrose, fatty acid, nucleotide and amino acid metabolisms increased. Pathways related to nutrient recycling processes were also up-regulated. Members of the NAC, AP2-EREBP, HB, bZIP and MYB transcription factor families showed high expression levels, and their expression level was highly correlated, suggesting their involvement in sunflower senescence. The results of this study thus contribute to the elucidation of the molecular mechanisms involved in the onset and progression of leaf senescence in sunflower leaves as well as to the identification of candidate genes involved in this process. Inst. de Biotecnología Fil: Moschen, Sebastian. Instituto Nacional de Tecnología Agropecuaria (INTA). Instituto de Biotecnología; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina Fil: Gonzalez, Sergio Alberto. Instituto Nacional de Tecnología Agropecuaria (INTA). Instituto de Biotecnología; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina Fil: Rivarola, Maximo Lisandro. Instituto Nacional de Tecnología Agropecuaria (INTA). Instituto de Biotecnología; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina Fil: Hopp, Horacio Esteban. Instituto Nacional de Tecnología Agropecuaria (INTA). Instituto de Biotecnología; Argentina. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales; Argentina Fil: Paniego, Norma Beatriz. Instituto Nacional de Tecnología Agropecuaria (INTA). Instituto de Biotecnología; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina Fil: Fernandez, Paula. Instituto Nacional de Tecnología Agropecuaria (INTA). Instituto de Biotecnología; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Universidad Nacional de San Martín. Escuela de Ciencia y Tecnología; Argentina Fil: Heinz, Ruth Amelia. Instituto Nacional de Tecnología Agropecuaria (INTA). Instituto de Biotecnología; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Universidad Nacional de Buenos Aires. Facultad de Ciencias Exactas y Naturales; Argentina Fil: Bengoa Luoni, Sofía. Universidad Nacional de San Martín. Escuela de Ciencia y Tecnología; Argentina Fil: Di Rienzo, Julio A. Universidad Nacional de Córdoba. Facultad de Ciencias Agropecuarias; Argentina Fil: Caro, María del Pilar. Consejo Nacional de Investigaciones Científicas y Técnicas. Instituto Superior de Investigaciones Biológicas; Argentina. Universidad Nacional de Tucumán; Argentina Fil: Tohge, Takayuki. Max-Planck-Institut fur Molekulare Pflanzenphysiologie; Alemania Fil: Watanabe, Mutsumi Max-Planck-Institut fur Molekulare Pflanzenphysiologie; Alemania Fil: Hollmann, Julien. University of Kiel. Institute of Botany, Christian-Albrechts; Alemania Fil: García-García, Francisco. Centro de Investigación Príncipe Felipe. Department of Bioinformatics and Genomics; España. Centro de Investigación Príncipe Felipe . National Institute of Bioinformatics. Functional Genomics Node; España Fil: Dopazo, Joaquín. Centro de Investigación Príncipe Felipe. Department of Bioinformatics and Genomics; España. Centro de Investigación Príncipe Felipe . National Institute of Bioinformatics. Functional Genomics Node; España Fil: Hoefgen, Rainer Max-Planck-Institut fur Molekulare Pflanzenphysiologie; Alemania Fil: Fernie, Alisdair R. Max-Planck-Institut fur Molekulare Pflanzenphysiologie; Alemania

Grain filling in sunflower (Helianthus annuus L.) mainly depends on actual photosynthesis, being the contribution of stored reserves in stems (sucrose, hexoses, and starch) rather low. Drought periods during grain filling often reduce yield. Increasing the capacity of stem to store reserves could help to increase grain filling and yield stability in dry years. Fructans improve water uptake in soils at low water potential, and allow the storage of large amount of assimilates per unit tissue volume that can be readily remobilized to grains. Sunflower is a close relative to Jerusalem artichoke (H. tuberosus L.), which accumulates large amounts of fructan (inulin) in tubers and true stems. The reason why sunflower does not accumulate fructans is obscure. Through a bioinformatics analysis of a sunflower transcriptome database, we found sequences that are homologous to dicotyledon and monocotyledon fructan synthesis genes. A HPLC analysis of stem sugar composition revealed the presence of low amounts of 1-kestose, while a drastic enhancement of endogenous sucrose levels by capitulum removal did not promote 1-kestose accumulation. This suggests that the regulation of fructan synthesis in this species may differ from the currently best known model, mainly derived from research on Poaceae, where sucrose acts as both a signaling molecule and substrate, in the induction of fructan synthesis. Thus, sunflower might potentially constitute a fructanbearing species, which could result in an improvement of its performance as a grain crop. However, a large effort is needed to elucidate how this up to now unsuspected potential could be effectively expressed. Fil: Martínez Noël, Giselle María Astrid. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Mar del Plata. Instituto de Investigaciones En Biodiversidad y Biotecnología; Argentina Fil: Dosio, Guillermo Aníbal Adrián. Universidad Nacional de Mar del Plata. Facultad de Ciencias Agrarias; Argentina Fil: Puebla, Andrea F.. Instituto Nacional de Tecnología Agropecuaria. Centro Nacional de Investigaciones Agropecuarias. Centro de Investigación de Ciencias Veterinarias y Agronómicas. Instituto de Biotecnología; Argentina Fil: Insani, Ester M.. Instituto Nacional de Tecnología Agropecuaria. Centro Nacional de Investigaciones Agropecuarias. Centro de Investigación de Ciencias Veterinarias y Agronómicas. Instituto de Biotecnología; Argentina Fil: Tognetti, Jorge A.. Universidad Nacional de Mar del Plata. Facultad de Ciencias Agrarias; Argentina. Provincia de Buenos Aires. Gobernación. Comisión de Investigaciones Científicas; Argentina

The pericarp anatomy and the effects of storage after harvest, storage temperature and early cypsela imbibition on phytohormone profiles were studied in inbred sunflower lines B123 and B91. On day 0, germination of B123 cypselas was near 0%, indicating dormancy, whereas that of B91 cypselas was near 100%, indicating non-dormancy. The germination of B123 and B91 on day 33 at room temperature (25 °C) storage was similar. Cell wall thickness and sclerification of the pericarp were higher in B123 than B91, suggesting that structural characteristics may contribute to physical dormancy in B123. Jasmonates (JAs), salicylic acid (SA) and abscisic acid (ABA) were measured in dry and imbibed pericarps. SA content of dry pericarp was higher on day 33 than day 0. SA content during imbibition on day 33 was similar for room and low (20 °C) storage temperatures. ABA content after 12 h imbibition was similar on days 0 and 33 at low temperature, but it increased on day 33 at room temperature for B123. 12-Oxophytodienoic acid (OPDA) was maximal on day 0 for B123, but peaked at day 33 at low temperature for B91. JA was higher on days 0 and 33 at room temperature as compared with low temperature. Our findings indicate that pericarp hormone profiles are affected in the two lines with different dormancy degree depending on storage conditions and imbibition processes. Fil: Andrade, Andrea Mariela. Universidad Nacional de Río Cuarto. Facultad de Ciencias Exactas, Fisicoquímicas y Naturales. Departamento de Ciencias Naturales; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina Fil: Riera, Natalí Vanesa. Universidad Nacional de Río Cuarto. Facultad de Ciencias Exactas, Fisicoquímicas y Naturales. Departamento de Ciencias Naturales; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina Fil: Lindström, Lilia Ivone. Universidad Nacional del Sur. Departamento de Agronomía; Argentina Fil: Alemano, Sergio Gabriel. Universidad Nacional de Río Cuarto. Facultad de Ciencias Exactas, Fisicoquímicas y Naturales. Departamento de Ciencias Naturales; Argentina Fil: Alvarez, Daniel. Instituto Nacional de Tecnología Agropecuaria; Argentina Fil: Abdala, Guillermina Irene. Universidad Nacional de Río Cuarto. Facultad de Ciencias Exactas, Fisicoquímicas y Naturales. Departamento de Ciencias Naturales; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina Fil: Vigliocco, Ana Edit. Universidad Nacional de Río Cuarto. Facultad de Ciencias Exactas, Fisicoquímicas y Naturales. Departamento de Ciencias Naturales; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina

Sclerotinia Head Rot (SHR), a disease caused by Sclerotinia sclerotiorum, is one of the most limiting factors in sunflower production. In this study, we identified genomic loci associated with resistance to SHR to support the development of assisted breeding strategies. We genotyped 114 Recombinant Inbred Lines (RILs) along with their parental lines (PAC2 ?partially resistant?and RHA266 ?susceptible?) by using a 384 single nucleotide polymorphism (SNP) Illumina Oligo Pool Assay to saturate a sunflower genetic map. Subsequently, we tested these lines for SHR resistance using assisted inoculations with S. sclerotiorum ascospores. We also conducted a randomized complete-block assays with three replicates to visually score disease incidence (DI), disease severity (DS), disease intensity (DInt) and incubation period (IP) through four field trials (2010?2014). We finally assessed main effect quantitative trait loci (M-QTLs) and epistatic QTLs (E-QTLs) by composite interval mapping (CIM) and mixed-model-based composite interval mapping (MCIM), respectively. As a result of this study, the improved map incorporates 61 new SNPs over candidate genes. We detected a broad range of narrow sense heritability (h2) values (1.86?59.9%) as well as 36 M-QTLs and 13 E-QTLs along 14 linkage groups (LGs). On LG1, LG10, and LG15, we repeatedly detected QTLs across field trials; which emphasizes their putative effectiveness against SHR. In all selected variables, most of the identified QTLs showed high determination coefficients, associated with moderate to high heritability values. Using markers shared with previous Sclerotinia resistance studies, we compared the QTL locations in LG1, LG2, LG8, LG10, LG11, LG15 and LG16. This study constitutes the largest report of QTLs for SHR resistance in sunflower. Further studies focusing on the regions in LG1, LG10, and LG15 harboring the detected QTLs are necessary to identify causal alleles and contribute to unraveling the complex genetic basis governing the resistance. Fil: Zubrzycki, Jeremías Enrique. Instituto Nacional de Tecnología Agropecuaria. Centro de Investigación en Ciencias Veterinarias y Agronómicas. Instituto de Biotecnología; Argentina Fil: Maringolo, Carla Andrea. Universidad Nacional de Mar del Plata; Argentina. Instituto Nacional de Tecnología Agropecuaria. Centro Regional Buenos Aires Sur. Estación Experimental Agropecuaria Balcarce; Argentina Fil: Filippi, Carla Valeria. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Instituto Nacional de Tecnología Agropecuaria. Centro de Investigación en Ciencias Veterinarias y Agronómicas. Instituto de Biotecnología; Argentina Fil: Quiroz, Facundo José. Instituto Nacional de Tecnología Agropecuaria. Centro Regional Buenos Aires Sur. Estación Experimental Agropecuaria Balcarce; Argentina Fil: Nishinakamasu, Verónica. Instituto Nacional de Tecnología Agropecuaria. Centro de Investigación en Ciencias Veterinarias y Agronómicas. Instituto de Biotecnología; Argentina Fil: Puebla, Andrea Fabiana. Instituto Nacional de Tecnología Agropecuaria. Centro de Investigación en Ciencias Veterinarias y Agronómicas. Instituto de Biotecnología; Argentina Fil: Di Rienzo, Julio Alejandro. Universidad Nacional de Córdoba. Facultad de Ciencias Agropecuarias. Departamento de Desarrollo Rural. Area de Estadística y Biometría; Argentina Fil: Escande, Alberto Raul. Instituto Nacional de Tecnología Agropecuaria. Centro de Investigación en Ciencias Veterinarias y Agronómicas. Instituto de Biotecnología; Argentina Fil: Lia, Verónica Viviana. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Instituto Nacional de Tecnología Agropecuaria. Centro de Investigación en Ciencias Veterinarias y Agronómicas. Instituto de Biotecnología; Argentina. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales; Argentina Fil: Heinz, Ruth Amelia. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Instituto Nacional de Tecnología Agropecuaria. Centro de Investigación en Ciencias Veterinarias y Agronómicas. Instituto de Biotecnología; Argentina. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales; Argentina Fil: Hopp, Horacio Esteban. Instituto Nacional de Tecnología Agropecuaria. Centro de Investigación en Ciencias Veterinarias y Agronómicas. Instituto de Biotecnología; Argentina. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales; Argentina Fil: Cervigni, Gerardo Domingo Lucio. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Rosario. Centro de Estudios Fotosinteticos y Bioquimicos. Universidad Nacional de Rosario. Facultad de Cs.bioquímicas y Farmaceuticas. Centro de Estudios Fotosinteticos y Bioquimicos; Argentina Fil: Paniego, Norma Beatriz. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Instituto Nacional de Tecnología Agropecuaria. Centro de Investigación en Ciencias Veterinarias y Agronómicas. Instituto de Biotecnología; Argentina

Background: Argentina has a long tradition of sunflower breeding, and its germplasm is a valuable genetic resource worldwide. However, knowledge of the genetic constitution and variability levels of the Argentinean germplasm is still scarce, rendering the global map of cultivated sunflower diversity incomplete. In this study, 42 microsatellite loci and 384 single nucleotide polymorphisms (SNPs) were used to characterize the first association mapping population used for quantitative trait loci mapping in sunflower, along with a selection of allied open-pollinated and composite populations from the germplasm bank of the National Institute of Agricultural Technology of Argentina. The ability of different kinds of markers to assess genetic diversity and population structure was also evaluated. Results: The analysis of polymorphism in the set of sunflower accessions studied here showed that both the microsatellites and SNP markers were informative for germplasm characterization, although to different extents. In general, the estimates of genetic variability were moderate. The average genetic diversity, as quantified by the expected heterozygosity, was 0.52 for SSR loci and 0.29 for SNPs. Within SSR markers, those derived from non-coding regions were able to capture higher levels of diversity than EST-SSR. A significant correlation was found between SSR and SNP- based genetic distances among accessions. Bayesian and multivariate methods were used to infer population structure. Evidence for the existence of three different genetic groups was found consistently across data sets (i.e., SSR, SNP and SSR + SNP), with the maintainer/restorer status being the most prevalent characteristic associated with group delimitation. Conclusion: The present study constitutes the first report comparing the performance of SSR and SNP markers for population genetics analysis in cultivated sunflower. We show that the SSR and SNP panels examined here, either used separately or in conjunction, allowed consistent estimations of genetic diversity and population structure in sunflower breeding materials. The generated knowledge about the levels of diversity and population structure of sunflower germplasm is an important contribution to this crop breeding and conservation. Instituto de Biotecnología Fil: Filippi, Carla Valeria. Instituto Nacional de Tecnología Agropecuaria (INTA). Instituto de Biotecnología; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina Fil: Aguirre, Natalia Cristina. Instituto Nacional de Tecnología Agropecuaria (INTA). Instituto de Biotecnología; Argentina Fil: Rivas, Juan Gabriel. Instituto Nacional de Tecnología Agropecuaria (INTA). Instituto de Biotecnología; Argentina Fil: Zubrzycki, Jeremias Enrique. Instituto Nacional de Tecnología Agropecuaria (INTA). Instituto de Biotecnología; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina Fil: Puebla, Andrea Fabiana. Instituto Nacional de Tecnología Agropecuaria (INTA). Instituto de Biotecnología; Argentina Fil: Cordes, Diego Darío. Instituto Nacional de Tecnología Agropecuaria (INTA). Estación Experimental Agropecuaria Manfredi; Argentina Fil: Moreno, Maria Valeria. Instituto Nacional de Tecnología Agropecuaria (INTA). Estación Experimental Agropecuaria Manfredi; Argentina Fil: Fusari, Corina Mariana. Instituto Nacional de Tecnología Agropecuaria (INTA). Instituto de Biotecnología; Argentina. Max Planck Institute of Molecular Plant Physiology; Alemania Fil: Alvarez, Daniel. Instituto Nacional de Tecnología Agropecuaria (INTA). Estación Experimental Agropecuaria Manfredi; Argentina Fil: Heinz, Ruth Amelia. Instituto Nacional de Tecnología Agropecuaria (INTA). Instituto de Biotecnología; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales; Argentina Fil: Hopp, Horacio Esteban. Instituto Nacional de Tecnología Agropecuaria (INTA). Instituto de Biotecnología; Argentina. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales; Argentina Fil: Paniego, Norma Beatriz. Instituto Nacional de Tecnología Agropecuaria (INTA). Instituto de Biotecnología; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina Fil: Lia, Veronica Viviana. Instituto Nacional de Tecnología Agropecuaria (INTA). Instituto de Biotecnología; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales; Argentina

Extracts of lipoxygenase were obtained from sunflower seeds using 12 different extraction mixtures, and lipoxygenase activity and content of phenolic compounds in the extracts were determined. The content of phenolic compounds was determined as the ratio of optical densities at 320/280nm. Statistical analysis of the results for the extracts showed a significant correlation between the lipoxygenase activity and the OD320nm/OD280nm ratio with r = 0.619. However, after dialysis of the extracts, no correlation was found.Efecto de los compuestos fenólicos extraídos de semillas de girasol sobre la actividad lipoxigenasa nativa. Se obtuvieron extractos de lipoxigenasa de semillas de girasol usando 12 mezclas de extracción diferentes, y se determinó la actividad lipoxigenasa y el contenido en compuestos fenólicos. Este último se llevó a cabo mediante medida de la relación de absorbancias a 320/280nm. El análisis estadístico de los resultados para los extractos mostró una correlación entre la actividad lipoxigenasa y la relación OD320nm/OD280nm con r = 0,619. Sin embargo, después de la diálisis de los extractos, no se observó esta correlación.

The effects of photosynthetic photon flux density (PPFD) and soil temperature on root system elongation rate have been analysed by using an architectural framework. Root elongation rate was analysed by considering three terms, (i) the branch appearance rate, (ii) the individual elongation rates of the taproot and branches and (iii) the proportion of branches which stop elongating. Large ranges ofPPFD and soil temperature were obtained in a series of field and growth chamber experiments. In the field, the growth of root systems experiencing day-to-day natural fluctuation of PPFD and temperature was followed, and some of the plants under study were shaded. In the growth chamber, plants experienced contrasting and constant PPFDs and root temperatures. The direct effect of apex temperature on individual root elongation rate was surprisingly low in the range 13–25°C, except for the first days after germination. Root elongation rate was essentially related to intercepted PPFD and to distance to the source, both in the field and in the growth chamber. Branch appearance rate substantially varied among days and environmental conditions. It was essentially linked to taproot elongation rate, as the profile of branch density along the taproot was quite stable. The length of the taproot segment carrying newly appeared branches on a given day was equal to taproot elongation on this day, plus a 'buffering term' which transiently increased if taproot elongation rate slowed down. The proportion of branches which stopped elongating a short distance from the taproot ranged from 50–80% and was, therefore, a major architectural variable, although it is not taken into account in current architectural models. A set of equations accounting for the variabilities in elongation rate, branch appearance rate and proportion of branches which stop elongating, as a function of intercepted PPFD and apex temperature is proposed. These equations apply for both field and growth chamber experiments. EEA Balcarce Fil: Aguirrezábal, Luis Adolfo Nazareno. Universidad Nacional de Mar del Plata. Facultad de Ciencias Agrarias. Cátedra de Fisiología Vegetal; Argentina. Instituto Nacional de Tecnología Agropecuaria (INTA). Estación Experimental Agropecuaria Balcarce; Argentina Fil: Tardieu, F. INRA. Laboratory d’Ecophysiologie des Plantes sous Stress Environnementaux; Francia

Sugars are part of an integrated redox system, since they are key regulators of respiration and photosynthesis, and therefore of the levels of reducing power, ATP and ROS. These elements are major determinants of the cellular redox state, which is involved in the perception and regulation of many endogenous and environmental stimuli. Our previous findings suggested that early sugar increase produced during compatible Sunflower chlorotic mottle virus (SuCMoV) infection might modulate chlorotic symptom development through redox state alteration in sunflower. The purpose of this work was to characterize redox-related metabolites and gene expression changes associated with high sugar availability and symptom development induced by SuCMoV. The results show that sugar caused an increase in glutathione, ascorbate, pyridine nucleotides, and ATP. In addition, higher sugar availability reduced hydrogen peroxide and ΦPSII. This finding suggests that high sugar availability would be associated with cellular redox alteration and photoinhibitory process. The expression of the genes analyzed was also strongly affected by sugar, such as the down-regulation of psbA and up-regulation of psbO and cp29. The expression level of cytoplasmic (apx-1 and gr)- and chloroplastic (Fe-sod)-targeted genes was also significantly enhanced in sugar-treated leaves. Therefore, all these responses suggest that sugars induce chloroplastic redox state alteration with photoinhibition process that could be contributing to chlorotic symptom development during SuCMoV infection. Fil: Rodriguez, Marianela Soledad. Instituto Nacional de Tecnología Agropecuaria. Centro de Investigaciones Agropecuarias. Instituto de Fisiología y Recursos Geneticos Vegetales; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina Fil: Muñoz, Nacira Belén. Instituto Nacional de Tecnología Agropecuaria. Centro de Investigaciones Agropecuarias. Instituto de Fisiología y Recursos Geneticos Vegetales; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina Fil: Lenardon, Sergio Luis. Instituto Nacional de Tecnología Agropecuaria. Centro de Investigaciones Agropecuarias. Instituto de Patología Vegetal; Argentina Fil: Lascano, Hernan Ramiro. Instituto Nacional de Tecnología Agropecuaria. Centro de Investigaciones Agropecuarias. Instituto de Fisiología y Recursos Geneticos Vegetales; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina

During microsporogenesis, sunflower florets might be exposed to episodes of day- and night-time temperatures exceeding 30 and 20 °C, respectively, that can affect pollen availability and consequently plant’s yield. The relationship between air temperature and relative humidity during the meiotic phase of microsporogenesis, and the quantity and quality of pollen produced by the flowers, were studied in two sunflower hybrids during two years. The hybrids were grown on irrigated plots in Bahía Blanca (38° 45’ S; 62° 11’ W) in three planting dates (PD) at a density of 5.6 plants/m2 . Flowers were consecutively taken as anthesis progressed, sectorizing the capitulum in three regions (external, middle and internal), to determine pollen grain number per flower (PGF) and pollen viability (PV). Both average air temperature (AT, °C) and relative humidity (RH, %) from reproductive stage R1 to R2 [36 to 48 days from emergence (DFE), respectively] were calculated for each PD, hybrid and capitulum sectors. Pollen viability was high (> 90%) with no differences between PD, capitulum sectors and hybrids. The number of PGF, with respect to AT (19 to 31 °C) from R1 to R2, was adjusted to a second-order polynomial (R2 =0.53, n=24; p 90%) no habiendo diferencias entre FS, sectores del capítulo e híbridos. El nú- mero de GPF respecto a la TMA (entre 19 y 31 °C) ocurrida entre R1 y R2 ajustó a un polinomio de segundo orden (R2 =0.53, n=24; p

Background/Objectives: Aging enhances frequency of chronic diseases like cardiovascular diseases or periodontitis. Here we reproduced an age-dependent model of the periodontium, a fully physiological approach to periodontal conditions, to evaluate the impact of dietary fat type on gingival tissue of young (6 months old) and old (24 months old) rats., Methods/Findings: Animals were fed life-long on diets based on monounsaturated fatty acids (MUFA) as virgin olive oil, n-6 polyunsaturated fatty acids (n-6PUFA), as sunflower oil, or n-3PUFA, as fish oil. Age-related alveolar bone loss was higher in n-6PUFA fed rats, probably as a consequence of the ablation of the cell capacity to adapt to aging. Gene expression analysis suggests that MUFA or n-3PUFA allowed mitochondria to maintain an adequate turnover through induction of biogenesis, autophagy and the antioxidant systems, and avoiding mitochondrial electron transport system alterations., Conclusions: The main finding is that the enhanced alveolar bone loss associated to age may be targeted by an appropriate dietary treatment. The mechanisms involved in this phenomenon are related with an ablation of the cell capacity to adapt to aging. Thus, MUFA or n-3PUFA might allow mitochondrial maintaining turnover through biogenesis or autophagy. They might also be able to induce the corresponding antioxidant systems to counteract age-related oxidative stress, and do not inhibit mitochondrial electron transport chain. From the nutritional and clinical point of view, it is noteworthy that the potential treatments to attenuate alveolar bone loss (a feature of periodontal disease) associated to age could be similar to some of the proposed for the prevention and treatment of cardiovascular diseases, a group of pathologies recently associated with age-related periodontitis., This study was supported by I+D grants from the Spanish Ministry of Education and Science (AGL2008-01057) and the Autonomous Government of Andalusia (AGR832).

Oligonucleotide-based microarrays with accurate gene coverage represent a key strategy for transcriptional studies in orphan species such as sunflower, H. annuus L., which lacks full genome sequences. The goal of this study was the development and functional annotation of a comprehensive sunflower unigene collection and the design and validation of a custom sunflower oligonucleotide-based microarray. A large scale EST (>130,000 ESTs) curation, assembly and sequence annotation was performed using Blast2GO (www.blast2go.de). The EST assembly comprises 41,013 putative transcripts (12,924 contigs and 28,089 singletons). The resulting Sunflower Unigen Resource (SUR version 1.0) was used to design an oligonucleotide-based Agilent microarray for cultivated sunflower. This microarray includes a total of 42,326 features: 1,417 Agilent controls, 74 control probes for sunflower replicated 10 times (740 controls) and 40,169 different non-control probes. Microarray performance was validated using a model experiment examining the induction of senescence by water deficit. Pre-processing and differential expression analysis of Agilent microarrays was performed using the Bioconductor limma package. The analyses based on p-values calculated by eBayes (p

Background: Sclerotinia Head Rot (SHR) is one of the most damaging diseases of sunflower in Europe, Argentina, and USA, causing average yield reductions of 10 to 20 %, but leading to total production loss under favorable environmental conditions for the pathogen. Association Mapping (AM) is a promising choice for Quantitative Trait Locus (QTL) mapping, as it detects relationships between phenotypic variation and gene polymorphisms in existing germplasm without development of mapping populations. This article reports the identification of QTL for resistance to SHR based on candidate gene AM. Results: A collection of 94 sunflower inbred lines were tested for SHR under field conditions using assisted inoculation with the fungal pathogen Sclerotinia sclerotiorum. Given that no biological mechanisms or biochemical pathways have been clearly identified for SHR, 43 candidate genes were selected based on previous transcript profiling studies in sunflower and Brassica napus infected with S. sclerotiorum. Associations among SHR incidence and haplotype polymorphisms in 16 candidate genes were tested using Mixed Linear Models (MLM) that account for population structure and kinship relationships. This approach allowed detection of a significant association between the candidate gene HaRIC_B and SHR incidence (P

Plants under water deficit reduce leaf growth, thereby reducing transpiration rate at the expense of reduced photosynthesis. The objective of this work was to analyse the response of leaf growth to water deficit in several sunflower genotypes in order to identify and quantitatively describe sources of genetic variability for this trait that could be used to develop crop varieties adapted to specific scenarios. The genetic variability of the response of leaf growth to water deficit was assessed among 18 sunflower (Helianthus annuus L.) inbred lines representing a broad range of genetic diversity. Plants were subjected to long-term, constant-level, water-deficit treatments, and the response to water deficit quantified by means of growth models at cell-, leaf-, and plant-scale. Significant variation among lines was found for the response of leaf expansion rate and of leaf growth duration, with an equal contribution of these responses to the variability in the reduction of leaf area. Increased leaf growth duration under water deficit is usually suggested to be caused by changes in the activity of cell-wall enzymes, but the present results suggest that the duration of epidermal cell division plays a key role in this response. Intrinsic genotypic responses of rate and duration at a cellular scale were linked to genotypic differences in whole-plant leaf area profile to water deficit. The results suggest that rate and duration responses are the result of different physiological mechanisms, and therefore capable of being combined to increase the variability in leaf area response to water deficit. EEA Balcarce Fil: Pereyra Irujo, Gustavo Adrian. Instituto Nacional de Tecnología Agropecuaria (INTA). Estación Experimental Agropecuaria Balcarce. Unidad Integrada. Universidad Nacional de Mar del Plata. Facultad de Ciencias Agrarias; Argentina Fil: Velazquez, Luciano. Instituto Nacional de Tecnología Agropecuaria (INTA). Estación Experimental Agropecuaria Balcarce. Unidad Integrada. Universidad Nacional de Mar del Plata. Facultad de Ciencias Agrarias; Argentina Fil: Lechner, Leandra. Instituto Nacional de Tecnología Agropecuaria (INTA). Estación Experimental Agropecuaria Balcarce. Unidad Integrada. Universidad Nacional de Mar del Plata. Facultad de Ciencias Agrarias; Argentina. Fil: Aguirrezábal, Luis Adolfo Nazareno. Instituto Nacional de Tecnología Agropecuaria (INTA). Estación Experimental Agropecuaria Balcarce. Unidad Integrada. Universidad Nacional de Mar del Plata. Facultad de Ciencias Agrarias; Argentina.

Background and Aims: Leaves expand during a given period of time until they reach their final size and form, which is called determinate growth. Duration of leaf expansion is stable when expressed in thermal-time and in the absence of stress, and consequently it is often proposed that it is controlled by a robust programme at the plant scale. The usual hypothesis is that growth cessation occurs when cell expansion becomes limited by an irreversible tightening of cell wall, and that leaf size is fixed once cell expansion ceases. The objective of this paper was to test whether leaf expansion could be restored by rewatering plants after a long soil water-deficit period. Methods: Four experiments were performed on two different species (Arabidopsis thaliana and Helianthus annuus) in which the area of leaves that had apparently reached their final size was measured upon reversal of water stresses of different intensities and durations. Key Results: Re-growth of leaves that had apparently reached their final size occurred in both species, and its magnitude depended only on the time elapsed from growth cessation to rewatering. Leaf area increased up to 186% in A. thaliana and up to 88% in H. annuus after rewatering, with respect to the leaves of plants that remained under water deficit. Re-growth was accounted for by cell expansion. Increase in leaf area represented actual growth and not only a reversible change due to increased turgor. Conclusions: After the leaf has ceased to grow, leaf cells retain their ability to expand for several days before leaf size becomes fixed. A response window was identified in both species, during which the extent of leaf area recovery decreased with time after the ‘initial’ leaf growth cessation. These results suggest that re-growth after rewatering of leaves having apparently attained their final size could be a generalized phenomenon, at least in dicotyledonous plants. EEA Balcarce Fil: Lechner, Leandra. Instituto Nacional de Tecnología Agropecuaria (INTA). Estación Experimental Agropecuaria Balcarce. Unidad Integrada. Universidad Nacional de Mar del Plata. Facultad de Ciencias Agrarias; Argentina. Fil: Pereyra Irujo, Gustavo Adrian. Instituto Nacional de Tecnología Agropecuaria (INTA). Estación Experimental Agropecuaria Balcarce. Unidad Integrada. Universidad Nacional de Mar del Plata. Facultad de Ciencias Agrarias; Argentina. Fil: Granier, Christine. Institut National de la Recherche Agronomique. Laboratoire d'Ecophysiologie des Plantes sous Stress Environnementaux; Francia Fil: Aguirrezábal, Luis Adolfo Nazareno. Instituto Nacional de Tecnología Agropecuaria (INTA). Estación Experimental Agropecuaria Balcarce. Unidad Integrada. Universidad Nacional de Mar del Plata. Facultad de Ciencias Agrarias; Argentina.

Con el propósito de evaluar la posible alteración en el desarrollo de los gametos masculinos en la progenie de un cruzamiento entre dos subespecies de girasol, se estudió la viabilidad del polen en la línea cultivada AN-3, así como en la subespecie silvestre Helianthus annuus ssp. texanus y en la descendencia híbrida resultante del cruzamiento CMS-AN-3 x H. annuus ssp. texanus. De las plantas híbridas, 95% exhibieron fertilidad masculina, lo cual indica la presencia de alelos restauradores de la fertilidad en las poblaciones silvestres. La viabilidad de polen no mostró diferencias significativas entre el híbrido (91.5%), el progenitor cultivado (94.6%) y el silvestre (95.2%). Los resultados sugieren que la viabilidad de polen es una característica mantenida en niveles altos tanto en las poblaciones silvestres como las cultivadas, y que no hay indicios de que la domesticación del girasol haya influido sobre este carácter. En lo que concierne al uso de material silvestre para el mejoramiento genético del girasol cultivado, la viabilidad de polen en los híbridos no es una barrera para el uso de poblaciones locales (sureste de Coahuila) de H. annuus ssp. texanus en programas de cruzamientos con fines de introducción de caracteres de plantas espontáneas a las variedades élite.

Cultivated sunflower (Helianthus annuus L.), an important source of edible vegetable oil, shows rapid onset of senescence, which limits production by reducing photosynthetic capacity under specific growing conditions. Carbon for grain filling depends strongly on light interception by green leaf area, which diminishes during grain filling due to leaf senescence. Transcription factors (TFs) regulate the progression of leaf senescence in plants and have been well explored in model systems, but information for many agronomic crops remains limited. Here, we characterize the expression profiles of a set of putative senescence associated genes (SAGs) identified by a candidate gene approach and sunflower microarray expression studies. We examined a time course of sunflower leaves undergoing natural senescence and used quantitative PCR (qPCR) to measure the expression of 11 candidate genes representing the NAC, WRKY, MYB and NF-Y TF families. In addition, we measured physiological parameters such as chlorophyll, total soluble sugars and nitrogen content. The expression of Ha-NAC01, Ha-NAC03, Ha-NAC04, Ha-NAC05 and Ha-MYB01 TFs increased before the remobilization rate increased and therefore, before the appearance of the first physiological symptoms of senescence, whereas Ha-NAC02 expression decreased. In addition, we also examined the trifurcate feed-forward pathway (involving ORE1, miR164, and ETHYLENE INSENSITIVE 2) previously reported for Arabidopsis. We measured transcription of Ha-NAC01 (the sunflower homolog of ORE1) and Ha-EIN2, along with the levels of miR164, in two leaves from different stem positions, and identified differences in transcription between basal and upper leaves. Interestingly, Ha-NAC01 and Ha-EIN2 transcription profiles showed an earlier up-regulation in upper leaves of plants close to maturity, compared with basal leaves of plants at pre-anthesis stages. These results suggest that the H. annuus TFs characterized in this work could play important roles as potential triggers of leaf senescence and thus can be considered putative candidate genes for senescence in sunflower. Fil: Moschen, Sebastián Nicolás. Instituto Nacional de Tecnología Agropecuaria. Centro de Investigación en Ciencias Veterinarias y Agronómicas. Instituto de Biotecnología; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina Fil: Bengoa Luoni, Sofia Ailin. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Universidad Nacional de San Martín. Escuela de Ciencia y Tecnología; Argentina Fil: Paniego, Norma Beatriz. Instituto Nacional de Tecnología Agropecuaria. Centro de Investigación en Ciencias Veterinarias y Agronómicas. Instituto de Biotecnología; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina Fil: Hopp, Horacio Esteban. Instituto Nacional de Tecnología Agropecuaria. Centro de Investigación en Ciencias Veterinarias y Agronómicas. Instituto de Biotecnología; Argentina. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales; Argentina Fil: Dosio, Guillermo Aníbal Adrián. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Universidad Nacional de Mar del Plata. Facultad de Ciencias Agrarias; Argentina. Instituto Nacional de Tecnología Agropecuaria. Centro Regional Buenos Aires Sur. Estación Experimental Agropecuaria Balcarce; Argentina Fil: Fernández, Paula del Carmen. Instituto Nacional de Tecnología Agropecuaria. Centro de Investigación en Ciencias Veterinarias y Agronómicas. Instituto de Biotecnología; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Universidad Nacional de San Martín. Escuela de Ciencia y Tecnología; Argentina Fil: Heinz, Ruth Amelia. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales; Argentina. Instituto Nacional de Tecnología Agropecuaria. Centro de Investigación en Ciencias Veterinarias y Agronómicas. Instituto de Biotecnología; Argentina

Protein content of residual meals of two sunflower cultivar during two harvest are evaluated. The relation between this component and the oil content of hull, achene and seed are showed. Negative tendency of correlation are observed between hull oil content and hull protein content, on achene oil content and achene protein content and on seed oil content and seed protein content along the harvest studied. Although the protein content for second harvest studied was lower, the apparent competitive behaviour between oil-protein was ratified.Se analizaron los contenidos proteicos de las harinas seminales residuales de extracción, correspondientes a cultivos de girasol (durante dos cosechas), con el fin de estudiar el comportamiento de esta variable en relación con los contenidos de aceite de los constituyentes de la semilla. Se realizaron correlaciones entre los contenidos proteicos de la cáscara, la pipa y la semilla, y la cantidad de aceite que éstos aportan, obteniendo tendencias de correlación negativas entre los mismos. A pesar que los contenidos proteicos obtenidos para la segunda cosecha fueron menores respecto de la primera, el comportamiento aparentemente competitivo entre aceite-proteína se ratificó con similar relevancia.