Evaluation of the efficiency of fungicides in controlling foliage soybean diseases in Tucumán, Argentina

Las enfermedades de la soja [Glycine max (L.) Merr.] constituyen un factor limitante de la producción cuando el cultivo se desarrolla bajo sistemas de manejo y condiciones ambientales favorables al desarrollo y dispersión de patógenos que lo afectan. Este trabajo muestra los resultados de cuatro años de evaluación a campo de la eficiencia del control químico de las enfermedades de fin de ciclo y la roya asiática de la soja, utilizando diferentes ingredientes activos y momentos de aplicación. Los ensayos se realizaron sobre A 8000 RG, grupo de maduración VIII, en la localidad de Puesto del Medio, departamento Burruyacú (Tucumán), durante las campañas 2007/2008, 2008/2009, 2009/2010 y 2010/2011. Los ingredientes activos evaluados fueron: flutriafol, pyraclostrobin + epoxiconazole, trifloxistrobin + cyproconazole, azoxistrobina + cyproconazole, picoxistrobin + cyproconazole, metominostrobin + tebuconazole, carbendazim + tebuconazole y cyproconazole + difenoconazole. Se aplicaron en los estadios fenológicos R3, R5 o R3+R5. Los parámetros evaluados fueron: severidad de las enfermedades (en R6), persistencia foliar (a inicios de R7), rendimiento del cultivo (kg/ha), peso de 1000 semillas (g), emergencia radicular (%) y porcentaje de infección en semillas. En la campaña 2007/2008, todos los tratamientos superaron al testigo en rendimiento y peso de 1000 semillas, presentando también menores niveles de enfermedad. No se detectaron diferencias significativas en el rendimiento y peso de 1000 semillas entre los tratamientos durante la campaña 2008/2009. Para las campañas 2009/2010 y 2010/2011, el tratamiento azoxistrobina + cyproconazole en R5 se diferenció del testigo en el rendimiento; en peso de 1000 semillas, trifloxistrobin + cyproconazole (R3) y azoxistrobina + cyproconazole (R3 y R5) se diferenciaron estadísticamente del testigo en la campaña 2009/2010, pero no se observaron diferencias para la campaña 2010/2011. En conclusión, la aplicación de fungicidas disminuyó los porcentajes de patógenos en la semilla, mejoró la emergencia radicular e incrementó los rendimientos de los cultivos, confirmando que existen ingredientes activos eficaces para el manejo de dichas patologías.Diseases may severely restrain soybean [Glycine max (L.) Merr.] production, especially when crops are grown under management systems and environmental conditions that favor the development and spread of pathogens. This paper reports the results of field trials which were conducted throughout four growing seasons, in order to evaluate the efficiency of different active ingredients and application timings in controlling diseases that affect soybean aerial parts, especially the late-season disease complex and Asian soybean rust. The trials were planted with A 8000 RG, a soybean cultivar from maturity group VIII, in Puesto del Medio, Burruyacú (Tucumán province), and were assessed during the 2007/2008, 2008/2009, 2009/2010 and 2010/2011 growing seasons. Evaluated active ingredients were flutriafol, pyraclostrobin + epoxiconazole, trifloxystrobin + cyproconazole, azoxystrobin + cyproconazole, picoxystrobin + cyproconazole, metominostrobin + tebuconazole, carbendazim + tebuconazole and cyproconazole + difenoconazole. Treatments were applied at R3, R5 or R3+R5 phenological states. Parameters assessed were: disease severity (at R6), foliar persistence (at early R7), crop yield (kg/ha), 1000-seed weight (g), seed emergence and seed infection (%). In the 2007/2008 season, all treatments were superior to the untreated control for disease control, crop yield, and 1000-seed weight. No statistically significant differences were found among treatments for yield and 1000-seed weight in the 2008/2009 season, whereas in the 2009/2010 and 2010/2011 seasons the only treatment that differed from the control in crop yield was the azoxystrobin + cyproconazole mix at R5. The trifloxystrobin + cyproconazole (at R3) and azoxystrobin + cyproconazole treatments (both at R3 and R5) differed from the control as regards 1000-seed weight in the 2009/2010 season, but no statistically significant differences were found among treatments in relation to this parameter in the 2010/2011 season. Fungicide applications generally decreased seed fungal infection, improved root emergence and increased crop yield, confirming that there are efficient active ingredients for the management of these diseases.Fil: Ploper, Leonardo Daniel. Gobierno de Tucumán. Ministerio de Desarrollo Productivo. Estación Experimental Agroindustrial Obispo Colombres; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Tucumán. Instituto de Tecnología Agroindustrial del Noroeste Argentino; Argentina; ArgentinaFil: González, Victoria. Gobierno de Tucumán. Ministerio de Desarrollo Productivo. Estación Experimental Agroindustrial Obispo Colombres; ArgentinaFil: Reznikov, Sebastian. Gobierno de Tucumán. Ministerio de Desarrollo Productivo. Estación Experimental Agroindustrial Obispo Colombres; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Tucumán. Instituto de Tecnología Agroindustrial del Noroeste Argentino; Argentina; ArgentinaFil: Hecker, Luis. Gobierno de Tucumán. Ministerio de Desarrollo Productivo. Estación Experimental Agroindustrial Obispo Colombres; ArgentinaFil: de Lisi, Vicente. Gobierno de Tucumán. Ministerio de Desarrollo Productivo. Estación Experimental Agroindustrial Obispo Colombres; ArgentinaFil: Henríquez, Diego D.. Gobierno de Tucumán. Ministerio de Desarrollo Productivo. Estación Experimental Agroindustrial Obispo Colombres; ArgentinaFil: Stegmayer, Carlos A.. Gobierno de Tucumán. Ministerio de Desarrollo Productivo. Estación Experimental Agroindustrial Obispo Colombres; ArgentinaFil: Devani, Mario R.. Gobierno de Tucumán. Ministerio de Desarrollo Productivo. Estación Experimental Agroindustrial Obispo Colombres; Argentin

Reference Values of Three-Dimensional Proximal Femur Parameters from Bone Densitometry Images in Healthy Subjects from Argentina

Objective: New methodologies for the assessment of bone mass from by DXA have been developed in the last years. The threedimensional analysis of the proximal femur by (3D-DXA) allows the evaluation of cortical and trabecular bone separately and has shown a good correlation with computed tomography. We aimed to obtain reference values in a healthy population of both sexesin Argentina.Methods: Adults female and male subjects (n=992) from four cities from Argentina were included. BMD (g/cm2) was measured by DXA on the femoral neck and total hip. The 3D analysis was performed with 3D-Shaper software (v2.9, Galgo Medical, Spain).The cortical BMD (sDens - mg/cm2) and trabecular volumetric BMD (trab vBMD - mg/cm3) were consider. The distribution of the data was evaluated with the Shapiro-Wilk test and parametricor non-parametric tests were used as appropriate. Data were expressed as mean±SD and p<0.05 was considered significant.Results: 75.5% women (n=749) and 24.5% men (n=243) were included. The mean age was 54.8±16.8 y and BMI was 27.3±5.4 kg/m2. The data according to each decade and a comparison with a references group (decade 20-30) are shown in the following table (*indicates significant differences compared to decade 20-30).Conclusion: A significant decrease in trabecular vBMD from D40 was observed in women, while in men this decrease was observed later (D60). The cortical parameter sDens was observed decreasefrom D50 in women and in men, an increase in D40 and cortical bone maintenance according to age was found.Fil: Brance, M. L.. Reumatología y Enfermedades Óseas; ArgentinaFil: Saravi, Fernando Daniel. Escuela de Medicina Nuclear; ArgentinaFil: Henríquez, M. M.. Escuela de Medicina Nuclear; ArgentinaFil: Longobardi, V.. Instituto de Investigaciones Metabólicas; ArgentinaFil: Zanchetta, M. B.. Instituto de Investigaciones Metabólicas; ArgentinaFil: Larroudé, M. S.. Centro de Diagnostico Rossi; ArgentinaFil: Ulla, M. R.. Instituto Latinoamericano de Investigaciones Médicas; ArgentinaFil: Matos, F.. Instituto Latinoamericano de Investigaciones Médicas; ArgentinaFil: Salerni, H.. No especifíca;Fil: Oliveri, María Beatriz. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Houssay. Instituto de Inmunología, Genética y Metabolismo. Universidad de Buenos Aires. Facultad de Medicina. Instituto de Inmunología, Genética y Metabolismo; Argentina. Universidad de Buenos Aires. Facultad de Medicina. Hospital de Clínicas General San Martín; ArgentinaFil: Bonanno, Marina Soledad. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Houssay. Instituto de Inmunología, Genética y Metabolismo. Universidad de Buenos Aires. Facultad de Medicina. Instituto de Inmunología, Genética y Metabolismo; Argentina. Universidad de Buenos Aires. Facultad de Medicina. Hospital de Clínicas General San Martín; ArgentinaFil: Meneses, N. L.. No especifíca;Fil: Di Gregorio, S.. Fundacion Cetir.; EspañaFil: Brum, L. R.. Universidad Nacional de Rosario; ArgentinaWorld Congress on Osteoporosis, Osteoarthritis and Musculoskeletal DiseasesVirtualBélgicaInternational Osteoporosis FoundationEuropean Society for Clinical and Economic Aspects of Osteoporosis, Osteoarthritis and Musculoskeletal Disease

The role of small GTPases in neuronal morphogenesis and polarity

The highly dynamic remodeling and cross talk of the microtubule and actin cytoskeleton support neuronal morphogenesis. Small RhoGTPases family members have emerged as crucial regulators of cytoskeletal dynamics. In this review we will comprehensively analyze findings that support the participation of RhoA, Rac, Cdc42, and TC10 in different neuronal morphogenetic events ranging from migration to synaptic plasticity. We will specifically address the contribution of these GTPases to support neuronal polarity and axonal elongation. © 2012 Wiley Periodicals, Inc

The Light Chain 1 Subunit of the Microtubule-Associated Protein 1B (MAP1B) Is Responsible for Tiam1 Binding and Rac1 Activation in Neuronal Cells

<div><p>Microtubule-associated protein 1B (MAP1B) is a neuronal protein involved in the stabilization of microtubules both in the axon and somatodendritic compartments. Acute, genetic inactivation of MAP1B leads to delayed axonal outgrowth, most likely due to changes in the post-translational modification of tubulin subunits, which enhances microtubule polymerization. Furthermore, MAP1B deficiency is accompanied by abnormal actin microfilament polymerization and dramatic changes in the activity of small GTPases controlling the actin cytoskeleton. In this work, we showed that MAP1B interacts with a guanine exchange factor, termed Tiam1, which specifically activates Rac1. These proteins co-segregated in neurons, and interact in both heterologous expression systems and primary neurons. We dissected the molecular domains involved in the MAP1B-Tiam1 interaction, and demonstrated that pleckstrin homology (PH) domains in Tiam1 are responsible for MAP1B binding. Interestingly, only the light chain 1 (LC1) of MAP1B was able to interact with Tiam1. Moreover, it was able to increase the activity of the small GTPase, Rac1. These results suggest that the interaction between Tiam1 and MAP1B, is produced by the binding of LC1 with PH domains in Tiam1. The formation of such a complex impacts on the activation levels of Rac1 confirming a novel function of MAP1B related with the control of small GTPases. These results also support the idea of cross-talk between cytoskeleton compartments inside neuronal cells.</p> </div

Tiam1 interacts with light chain 1 (LC1) of MAP1B.

<p>Overexpression of Myc-tagged MAP1B constructs in COS7 cells and N1E115 cells was analyzed by immunoprecipitation (IPP) with anti-myc antibodies followed by Western blotting (Wb) against endogenous Tiam-1 for N1E115 or Tiam-HA for COS7 cells. (A) myc-tagged MAP1B constructs expressed in COS7 cells are differentially recovered by HA-Tiam1. Note that only myc-LC1 subunit interact with Tiam1. (B) All myc-tagged MAP1B FL, HC and LC1 constructs expressed in N1E115 cells were able to recover Tiam1. (C) Only endogeneous N1E115 LC1 protein was recovered with Tiam1 under high stringent conditions (see <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0053123#s2" target="_blank">materials and methods</a>). (D) Myc-tagged MAP1B constructs expression in whole cell lysates. Full length (FL), Heavy chain (HC), and Light chain (LC) of MAP1B expressed in N1E115 (A) or COS7 (C) cells.</p

N-PH and C-PH domains of Tiam 1 interact with both domains of the light chain 1 (LC1) of MAP1B.

<p>Pull down assays using GST-fusion proteins of LC1, indicated by western blots using anti-GST antibody (bottom of each panel), were incubated with lysates of COS7 cells expressing T2 (N-PH) or T5 (C-PH). Both fragments of Tiam1 (T2 and T5) interacted with NTD and CTD of LC1.</p

Tiam1 interacts with the N- and C-terminal domains of LC1.

<p>(<b>A</b>) Schematic representation of GST protein fused to LC1. Numbers refer to the amino acid positions in mouse MAP1B. <b>NTD</b>, N-terminal domain (microtubule binding domain); <b>CTD</b>, C-terminal domain (actin binding domain). (<b>B</b>) and (<b>D</b>) Coomassie brilliant blue stain (CBBS) of GST proteins used in pull down assays and immunoblot using anti-GST antibody. (<b>C</b>) and (<b>E</b>) Pull down assay using LC1-GST full length or isolated N- and C-terminal domains were incubated with fetal brain lysates. The bound protein was analyzed by immunoblotting with anti-Tiam 1 antibody. The arrows on the right-hand side of the images show the band corresponding to Tiam1.</p

Mapping of the region in Tiam 1 that is required for binding to LC1.

<p>LC1-GST immobilized beads were incubated with cell lysates of COS7 cells expressing the FLAG-Tiam1 constructs. As indicated in (<b>A</b>), only domains containing the pleckstrin domain of Tiam 1 (T2 and T5) interact with LC1-GST, as visualized by immunoblotting using an anti-FLAG antibody. (<b>B</b>) Panel shows the total lysate of COS7 cells expressing each of the Tiam1 fragment proteins used for the pull down assays. (<b>C</b>) N-PH (T2) and C-PH (T5) interacted with LC1 in immunoprecipitation assays of Tiam1 fragments with LC1-Myc. Proteins were expressed in COS7 cells (<b>D</b>) (input of immunoprecipitation reaction).</p

Tiam1 colocalizes with MAP1B and displays polarized distribution in hippocampal neurons during polarization.

<p>Hippocampal neurons grown for 24 (A), 48 (B) and 72 (D) hours in vitro and stained with MAP1B (green), Tiam1 (red) and axonal marker tau-1 (white). (C) and (E) shown a zoom of the MAP1B/Tiam1 merged channel (white square in B and D). Tiam1 and MAP1B are concentrated at the tip of the axon at 48 and 72 hrs in culture.</p

Deletion constructs of Tiam 1 containing a FLAG epitope at the N-terminal.

<p>(<b>A</b>) Schematic representation of Tiam1 and the deletion mutants. The numbers refer to the amino acid positions in mouse Tiam1. T1, N-terminal domain and PEST motif; T2, N-terminal pleckstrin domain (N-PH); T3, Ras binding domain (RBD) and PDZ domain; T4, Dbl-homology domain (DH) and T5 C-terminal pleckstrin domain (C-PH). (<b>B</b>) immunoblotting showing the expression of the FLAG-Tiam1 constructs in COS-7 cells.</p