Efecto de los herbicidas fomesafen y biciclopirona sobre la microbiota del suelo en secuencias de cultivo con soja y maíz

PosterLos microorganismos del suelo son responsable del control de funciones esenciales: la descomposición y acumulación de materia orgánica, cambios en la disponibilidad de nutrientes minerales o degradación de compuestos xenobióticos. Los plaguicidas suelen tener efectos deletéreos sobre los microorganismos del suelo afectando los procesos de degradación biológicos. Fomesafen y Biciclopirona son herbicidas de larga persistencia eficaces para el control de amarantáceas en soja y maíz, cuya residualidad puede afectar de manera sustancial la microbiota del suelo. Se planteó como objetivo, estudiar los efectos de la aplicación de ambos herbicidas sobre la biomasa de la microbiota del suelo, cuantificando el contenido de carbono de la biomasa microbiana (CBM) que determina la cantidad global de microorganismos presentes.EEA AnguilFil: Azcarate, Mariela Pamela. Instituto Nacional de Tecnología Agropecuaria (INTA). Estación Experimental Agropecuaria Anguil; ArgentinaFil: Montoya, Jorgelina. Instituto Nacional de Tecnología Agropecuaria (INTA). Estación Experimental Agropecuaria Anguil; ArgentinaFil: Frasier, Ileana. Instituto Nacional de Tecnología Agropecuaria (INTA). Estación Experimental Agropecuaria Anguil; ArgentinaFil: Porfiri, Carolina. Instituto Nacional de Tecnología Agropecuaria (INTA). Estación Experimental Agropecuaria Anguil; Argentin

Estudio de la distribución geográfica de los quimiotipos de Fusarium graminearum aislados de trigo cultivado en Argentina y de los principales géneros de su micoflora acompañante

Fil: Azcarate, Mariela Pamela. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales; Argentina

Estudio de la distribución geográfica de los quimiotipos de Fusarium graminearum aislados de trigo cultivado en Argentina y de los principales géneros de su micoflora acompañante

Fil: Azcarate, Mariela Pamela. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales; Argentina

Sorption, desorption and leaching potential of sulfonylurea herbicides in Argentinean soils

The sulfonylurea (SUs) herbicides are used to control broadleaf weeds and some grasses in a variety of crops. They have become popular because of their low application rates, low mammalian toxicity and an outstanding herbicidal activity. Sorption is a major process influencing the fate of pesticides in soil. The objective of this study was to characterize sorption–desorption of four sulfonylurea herbicides: metsulfuron-methyl (methyl 2-[(4-methoxy-6-methyl-1,3,5-triazin-2-yl)carbamoylsulfamoyl)] benzoate), sulfometuron-methyl (methyl 2-[(4,6-dimethylpyrimidin-2-yl)carbamoylsulfamoyl]benzoate), rimsulfuron (1-(4,6- dimethoxypyrimidin-2-yl)-3-(3-ethylsulfonyl-2-pyridylsulfonyl)urea) and nicosulfuron (2-[(4,6-dimethoxypyrimidin-2-yl) carbamoylsulfamoyl]-N,N-dimethylnicotinamide) from different soil horizons of different landscape positions. Sorption was studied in the laboratory by batch equilibration method. Sorption coefficients (Kd-SE) showed that rimsulfuron (Kd-SE D 1.18 to 2.08 L kg -1) and nicosulfuron (Kd-SE D 0.02 to 0.47 L kg -1) were more highly sorbed than metsulfuron-methyl (Kd-SE D 0.00 to 0.05 L kg -1) and sulfometuron-methyl (Kd-SE D 0.00 to 0.05 L kg -1). Sorption coefficients (Kd-SE) were correlated with pH and organic carbon content. All four herbicides exhibited desorption hysteresis where the desorption coefficients (Kd-D) > Kd-SE. To estimate the leaching potential, Koc and ground-water ubiquity score (GUS) were used to calculate the half-life (t1/2) required to be classified as “leacher” or “nonleacher”. According to the results, rimsulfuron and nicosulfuron herbicides would be classified as leachers, but factors such as landscape position, soil depth and the rate of decomposition in surface and subsurface soils could change the classification. In contrast, these factors do not affect classification of sulfometuron-methyl and metsulfuron-methyl; they would rank as leachers.Fil: Azcarate, Mariela Pamela. Instituto Nacional de Tecnología Agropecuaria (INTA). Estación Experimental Agropecuaria Anguil; ArgentinaFil: Montoya, Jorgelina Ceferina. Instituto Nacional de Tecnología Agropecuaria (INTA). Estación Experimental Agropecuaria Anguil; ArgentinaFil: Koskinen, William C. Department of Agriculture. Agricultural Research Service. Soil and Water Management Research Unit; Estados Unido

Adsorption and transport of imazapyr through intact soil columns taken from two soils under two tillage systems

The objective of this work was to study the sorption and transport of imazapyr (IMZ) in two soils with different physical–chemical properties, subject to long-term conventional tillage (CT) and no-tillage (NT) systems. Sorption was carried out using batch equilibrium method and high performance liquid chromatography analytical routines. Displacement experiments through intact soil cores were done using IMZ as reactive solute and bromide (Br) as non-reactive solute. Equilibrium (CDEeq) and non-equilibrium (CDEnon-eq) transport models (CXTFIT 2.1) were employed to describe the breakthrough curves (BTCs). IMZ was only sorbed by NT soils with Kd values ranging from 0.22 to 1.1 L kg−1 . Clay content, pH and CEC values were the main factors affecting the sorption of IMZ. Miscible displacement studies showed that almost all the soil water was mobile and transport was related to physical equilibrium conditions. Some evidence of sorption non-equilibrium was seen in column experiments with IMZ; retardation factors were close to one, demonstrating the low sorption and the high potential to leach of this compound.Fil: Porfiri, Carolina. Instituto Nacional de Tecnología Agropecuaria (INTA). Estación Experimental Agropecuaria Anguil; ArgentinaFil: Montoya, Jorgelina Ceferina. Instituto Nacional de Tecnología Agropecuaria (INTA). Estación Experimental Agropecuaria Anguil; ArgentinaFil: Koskinen, William C. Department of Agriculture. Agricultural Research Service. Soil and Water Management Research Unit; Estados UnidosFil: Azcarate, Mariela Pamela. Instituto Nacional de Tecnología Agropecuaria (INTA). Estación Experimental Agropecuaria Anguil; Argentin

Alternaria toxins in wheat during the 2004 to 2005 Argentinean harvest

The natural occurrence of Alternaria mycotoxins in Argentinean wheat from the zone 5 South during the 2004 to 2005 harvest was investigated in 64 wheat samples. All samples were highly contaminated with a wide range of fungal species. Alternaria was found as the main component of the mycota, with an infection percentage of 100%. Three mycotoxins produced by species of Alternaria were determined in wheat: alternariol, alternariol monomethyl ether, and tenuazonic acid. Alternariol was detected in 4 (6%) of 64 samples, with a range of 645 to 1,388 μg/kg (mean of 1,054 μg/kg); alternariol monomethyl ether, with a range of 566 to 7,451 μg/kg (mean of 2,118 μg/kg) in 15 (23%) of 64 samples; and tenuazonic acid in 12 (19%) of 64 samples, with a range of 1,001 to 8,814 μg/kg (mean, 2,313 μg/kg). Alternariol monomethyl ether was the predominant toxin, but tenuazonic acid was detected in higher concentrations. Alternariol was present in fewer samples and in lower levels than were the other toxins. Tenuazonic acid and alternariol monomethyl ether occurred together in four samples, while tenuazonic acid and alternariol co-occurred in one sample. This the first report of the natural occurrence of Alternaria mycotoxins in Argentinean wheat. Toxin levels were high, probably due to the heavy infection with Alternaria species found in the samples.Fil: Azcarate, Mariela Pamela. Instituto Nacional de Tecnología Agropecuaria. Centro Regional La Pampa-San Luis. Estación Experimental Agropecuaria Anguil; ArgentinaFil: Patriarca, Andrea Rosana. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Ciudad Universitaria. Instituto de Micología y Botánica. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Instituto de Micología y Botánica; ArgentinaFil: Terminiello, Laura Adriana. Universidad Nacional de La Plata; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Fernández Pinto, Virginia. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Departamento de Química Orgánica; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentin

Métodos de análisis e implementación de calidad en el Laboratorio de Suelos

En esta publicación el lector encontrará resultados de investigación referidos a métodos de análisis de suelos y experiencias de la implementación de un Sistema de Gestión de Calidad siguiendo el lineamiento de la Norma IRAM 301:2005 (ISO/IEC 17025:2005).EEA AnguilFil: Azcarate, Mariela Pamela. Instituto Nacional de Tecnología Agropecuaria (INTA). Estación Experimental Agropecuaria Anguil; ArgentinaFil: Baglioni, Micaela. Universidad Nacional de La Pampa. Facultad de Ciencias Exactas y Naturales; ArgentinaFil: Brambilla, Clara. Universidad Nacional de La Pampa. Facultad de Ciencias Exactas y Naturales; ArgentinaFil: Brambilla, Emilio Cesar. Instituto Nacional de Tecnología Agropecuaria (INTA). Estación Experimental Agropecuaria Balcarce; ArgentinaFil: Fernandez, Romina. Instituto Nacional de Tecnología Agropecuaria (INTA). Estación Experimental Agropecuaria Anguil; ArgentinaFil: Noellemeyer, Elke. Universidad Nacional de La Pampa. Facultad de Agronomía; ArgentinaFil: Ostinelli, Miriam Mabel. Instituto Nacional de Tecnología Agropecuaria (INTA). Instituto de Suelos; ArgentinaFil: Perez, Maria Micaela. Instituto Nacional de Tecnología Agropecuaria (INTA). Estación Experimental Agropecuaria Anguil; ArgentinaFil: Quiroga, Alberto Raul. Instituto Nacional de Tecnología Agropecuaria (INTA). Estación Experimental Agropecuaria Anguil; ArgentinaFil: Savio, Marianela. Universidad Nacional de La Pampa. Facultad de Ciencias Exactas y Naturales; ArgentinaFil: Kloster, Nanci Soledad. Instituto Nacional de Tecnología Agropecuaria (INTA). Estación Experimental Agropecuaria Anguil; Argentin