Emisiones de gases efecto invernadero en caña de azúcar en Tucumán, Argentina: incidencia del quemado del rastrojo y la fertilización nitrogenada

En la caña de azúcar, la aplicación de fertilizante nitrogenado y el quemado de rastrojo post-cosecha son prácticas que liberan gases de efecto invernadero (GEI), perjudicando la sustentabilidad de la producción. Con el objetivo de determinar el efecto de dichas prácticas de manejo sobre las emisiones de dióxido de carbono (CO2), óxido nitroso (N2O) y metano (CH4) durante el ciclo de cultivo y sobre los balances de carbono del suelo, se estableció un experimento a campo durante tres ciclos agrícolas consecutivos, utilizando la metodología de las cámaras estáticas. Los tratamientos evaluados fueron cuatro manejos en caña de azúcar: i) con quema del rastrojo y fertilización nitrogenada; ii) con quema del rastrojo sin fertilización nitrogenada iii) sin quema del rastrojo con fertilización nitrogenada; iv) sin quema del rastrojo sin fertilización nitrogenada; y un sistema de referencia: v) monte nativo. La caña de azúcar posee un balance positivo (secuestro) potencial de 2.03 t ha-1 de carbono, el cual es reducido debido a la quema del rastrojo y la no fertilización nitrogenada. La quema del rastrojo incrementó las emisiones de N2O cuando se aplicó fertilizante. La aplicación anual de urea en el tratamiento sin quema de rastrojo resultó en un factor de emisión promedio (en condiciones climáticas modales de esta área cañera) de 0,73%. Este factor fue menor que el factor propuesto por defecto (1%) por el Panel Intergubernamental para el Cambio Climático (IPCC). Las emisiones acumuladas de CH4 para los tratamientos con caña de azúcar no superaron los 1,2 kg de C-CH4 ha-1 año-1; mientras que para el tratamiento de monte nativo hubo capturas significativas y regulares de CH4 durante todos los ciclos agrícolas. Estrategias de mitigación como evitar la quema del rastrojo y/o disminuir la dosis de fertilización nitrogenada pueden reducir las emisiones totales de GEI de esta agroindustria en Tucumán.Fil: Chalco Vera, Jorge Elías. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Tucumán; Argentina. Universidad Nacional de Tucumán. Facultad de Agronomía y Zootecnia; Argentina. Instituto Nacional de Tecnología Agropecuaria. Centro Regional Tucuman-Santiago del Estero. Estación Experimental Agropecuaria Famaillá; Argentin

Towards a baseline for reducing the carbon budget in sugarcane: three years of carbon dioxide and methane emissions quantification

Sugarcane straw burning or removal and N fertilization are management practices that modify the input of carbon (C) to the soil affecting greenhouse gases emissions and the potential of the soil for C sequestration. This study aimed to determine the effect of post-harvest straw burning and synthetic N fertilization on the dynamics of CO2 and CH4 fluxes in the sugarcane-soil system of Tucuman, Argentina; it also compared these emissions with those of a native forest and discussed a theoretical soil C balance based on C emissions. Close-vented chambers were used to capture CO2 and CH4 during three consecutive growing seasons. The higher CO2 emissions coincided with the period of high soil and air temperatures and rainfalls. There was not a clear pattern in the dynamics of CH4 flux for all sugarcane treatments, while the native forest consistently captured CH4; however, the cumulative CH4 flows were negligible in term of C mass. Annual cumulative CO2 emissions were 12.4–61.4 and 5.9–51.5% higher (for N-fertilized and unfertilized treatments, respectively) when straw was not burned regarding to the burned treatment. However, C losses -as CO2 emissions- in unburnt treatments were lower than the C input from straw and roots, while C losses in burnt treatments were higher than C input from straw and roots. The soil-sugarcane system of Tucuman has a potential C sequestration estimated of 2.03 Mg of C ha−1 yr−1. The results of this manuscript highlighted the importance of preserving straw as a way to maintain or increase soil organic carbon. They also demonstrated the importance of considering management practices when measuring CO2 fluxes during the crop cycle for determining the soil C balance.Fil: Chalco Vera, Jorge Elías. Instituto Nacional de Tecnología Agropecuaria. Centro Regional Tucuman-Santiago del Estero. Estación Experimental Agropecuaria Famaillá; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Acreche, Martin Moises. Instituto Nacional de Tecnología Agropecuaria. Centro Regional Buenos Aires; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentin

Emisiones provinciales de gases con efecto invernadero del sistema suelo-caña de azúcar de Tucumán

Las estimaciones de emisiones de gases con efecto invernadero (GEI) de suelos agrícolas informadas en el último Reporte Bienal de Actualización de Argentina en 2017 presentan gran incertidumbre debido a que se basan en el uso de factores de emisión del IPCC y no en mediciones directas a campo, lo cual limita la capacidad de planificar un desarrollo sostenible de bajas emisiones de GEI. El objetivo de este trabajo fue calcular las emisiones medidas de GEI de la caña de azúcar para la provincia de Tucumán y compararlas con las emisiones determinadas siguiendo el protocolo del IPCC. El cálculo y análisis de las emisiones de GEI se realizó por extrapolación e interpolación de flujos medios medidos a campo durante los ciclos agrícolas 2013-2014 y 2014-2015. Las emisiones totales de GEI (CH4 + N2 O) de la caña de azúcar en Tucumán fueron 343,6 Gg CO2 eq. para el ciclo agrícola 2013-2014 (normal a seco) y 404,9 Gg CO2 eq. para el ciclo agrícola 2014-2015 (húmedo). En un ciclo de precipitaciones modales se demostró que: i) el IPCC sobrestimó las emisiones provinciales en un 18,4%; y ii) una disminución de la superficie quemada se traduciría en un mayor porcentaje de sobrestimación por parte del IPCC. La brecha más importante con el IPCC está dada por el manejo de rastrojo y las emisiones durante el ciclo agrícola del cultivo. La prevención de la quema del rastrojo de la caña de azúcar conduce efectivamente a disminuir las emisiones totales de GEI de Tucumán, lo que puede revertir el efecto adverso sobre el incremento de las emisiones totales de GEI de los eventos extremos de alta precipitación.Estimations of GHG emissions from agricultural soils reported in the latest Biennial Update Report of Argentina of 2017 present great uncertainty because they are based on IPCC emission factors and not on direct field measurements. This limits the ability for planning a sustainable development of low GHG emissions. The objective of this work was to quantify the GHG emissions of sugarcane measured for the province of Tucumán and compare them with the emissions determined following the IPCC protocol. The quantification and analysis of GHG emissions was carried out by extrapolation and interpolation of mean flows measured in the field during the 2013-2014 and 2014-2015. The total emissions of GHG (CH4 + N2O) from sugarcane in Tucumán were 343.6 and 404.9 Gg CO2 eq. for the 2013-2014 (normal to dry) and 2014-2015 (wet) growing seasons, respectively. It was shown that, in a growing season of modal rainfall: i) the IPCC overestimated provincial emissions by 18.4%; and ii) a decrease in the burned area increased the overestimation by the IPCC. The most important gap with the IPCC was given by straw management and the emissions during the growing season. The prevention of straw burning effectively leads to a reduction in total GHG emissions from the sugarcane-soil system of Tucumán, which can reverse the adverse effect on the increase of total GHG emissions from extreme events of high rainfall.Fil: Chalco Vera, Jorge Elías. Instituto Nacional de Tecnología Agropecuaria. Centro Regional Tucuman-Santiago del Estero. Estación Experimental Agropecuaria Famaillá; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Tucumán; ArgentinaFil: Acreche, Martin Moises. Instituto Nacional de Tecnología Agropecuaria. Centro Regional Salta-Jujuy. Estación Experimental Agropecuaria Salta; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Salta; Argentin

Integrating critical values of soil drivers for mitigating GHGs: An assessment in a sugarcane cropping system

Agricultural practices can reduce emissions of greenhouse gases (GHG). The definition of management practices toward mitigating GHG emissions could gain accuracy by integrating critical values of soil variables related to GHG fluxes. The aim of this study was to combine critical values of soil variables determining groups of GHG fluxes with similar and/or opposite direction of carbon dioxide (CO2), nitrous oxide (N2O) and methane (CH4). We determined CO2, N2O, CH4 fluxes, soil temperature, gravimetric soil moisture (GSM), soil inorganic nitrogen (SIN), soil bulk density (SBD), soil porosity (P), and water-filled pore space (WFPS) monthly in three consecutive growing seasons in a sugarcane agroecosystem. The regression tree method defined groups of emission. Six terminal groups of CO2, N2O fluxes, and four for CH4 fluxes were determined. The critical values of soil variables that defined the terminal groups with the highest fluxes were soil temperature (>19 °C) and GSM (>35.2%) for CO2, GSM (>29.2%) and SIN (≤1.1 ppm) for N2O, and GSM (>24.9 °C), SBD (>0.98 g cm−3) and SIN (>1.82 ppm) for CH4. Trade-offs were found among GHGs: N2O emissions were high and CO2 emissions were low when GSM and soil temperature ranged from 29 to 35% and 14–19 °C, respectively (moderate values). CO2 emissions were high and N2O emissions were the lowest when GSM was equal or lower than 29.2% and soil temperature ranged from 19 to 21.3 °C. In this study, we highlight that management practices aimed to mitigate GHG fluxes should consider the integrated analysis of critical values of soil variables for GHGs together in order to avoid trade-offs.Fil: Chalco Vera, Jorge Elías. Instituto Nacional de Tecnología Agropecuaria. Centro Regional Salta-Jujuy. Estación Experimental Agropecuaria Salta; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Salta; ArgentinaFil: Curti, Ramiro Nestor. Universidad Nacional de Salta. Facultad de Ciencias Naturales; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Salta; ArgentinaFil: Acreche, Martin Moises. Instituto Nacional de Tecnología Agropecuaria. Centro Regional Salta-Jujuy. Estación Experimental Agropecuaria Salta; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Salta; Argentin

Is it possible to mitigate nitrous oxide emissions by improving the nitrogen use efficiency?

La fertilización nitrogenada aumenta las tasas de emisión de óxido nitroso (tN2O), el más potente de los gases con efecto invernadero. Se determinó en caña de azúcar las tN2O, la eficiencia fisiológica y de uso de nitrógeno (EFN y EUN, respectivamente) en cuatro tratamientos de fertilización: sin fertilizante (SF), con urea (55 y 110 kgN ha ) (US y UC, respectivamente) y con nitrato de amonio (110 kgN ha-1) (NA). LastN2O se midieron quincenalmente utilizando cámaras estáticas. Los promedios de tN2O de cuatro muestreos pos-fertilización fueron:77.5±19.6; 137.6±24.2; 145.2±25.7 y 179.5±39.4 µg N-N2O m-1 h-1 para los tratamientos SF, US, UC y NA, respectivamente. Las mayorestN2O se asociaron a menores valores de EFN y EUN. A igualdad de dosis nitrogenada, la EUN fue de 123.4 y 103.3 kg tallo seco por kgN disponible en el suelo para UC y NA, respectivamente; mientras que la EFN fue de 183.4 y 145.6 kg tallo por kgN absorbido. Los resultados obtenidos sugieren que además de reducir las dosis de fertilizante, aumentar la EUN y la EFN con formulaciones alternativas puede reducirlas tN2O. Sin embargo, más mediciones de emisiones concentradas en la pos-fertilización es clave para aumentar la precisión de estos.Fil: Chalco Vera, Jorge Elías. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Salta; Argentina. Instituto Nacional de Tecnología Agropecuaria. Centro Regional Salta-Jujuy. Estación Experimental Agropecuaria Salta; ArgentinaFil: Portocarrero, Rocio de Los Angeles. Instituto Nacional de Tecnología Agropecuaria. Centro Regional Tucuman-Santiago del Estero. Estación Experimental Agropecuaria Famaillá; ArgentinaFil: Acreche, Martin Moises. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Salta; Argentina. Instituto Nacional de Tecnología Agropecuaria. Centro Regional Salta-Jujuy. Estación Experimental Agropecuaria Salta; ArgentinaXXXII Reunión Argentina de Fisiología Vegetal; XV Congreso Latinoamericano de Fisiología VegetalCórdobaArgentinaSociedad Argentina de Fisiología Vegeta

To burn or not to burn: The question of straw burning and nitrogen fertilization effect on nitrous oxide emissions in sugarcane

Nitrous oxide (N2O) is the main greenhouse gas emitted from farming systems and is associated with nitrogen (N) fertilizer application as well as decomposition of organic matter present in the environment. The objective of this study was to determine the effect of post-harvest straw burning and synthetic N fertilization on the dynamics of N2O emissions in the sugarcane-soil system in Tucuman, Argentina, compared with a native forest. Close-vented chambers were used to capture N2O during three consecutive growing seasons. The highest N2O emissions from the sugarcane-soil system coincided with the period of high soil and air temperatures, rainfall and soil N content. The effect of synthetic N fertilization on annual cumulative N2O emission was 7.4–61.5% higher in straw burned than in unburned treatments, especially during a wet growing season. There was a significant effect of treatments on N2O emission factors among growing seasons: 0.58–1.67% and 0.94–3.34% in the unburnt and burnt treatments, respectively. The emission factors for sugarcane are highly dependent on rainfall, temperature and crop management practices; regarding the latter, avoiding straw burning and reducing N soil availability, assessing alternative N fertilizers or new application modes such as split rates, seem to be the key for mitigating N2O emissions from the sugarcane-soil system in Tucumán, Argentina.Fil: Chalco Vera, Jorge Elías. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Instituto Nacional de Tecnología Agropecuaria. Centro Regional Tucuman-Santiago del Estero. Estación Experimental Agropecuaria Famaillá; ArgentinaFil: Valeiro, Alejandro. Instituto Nacional de Tecnología Agropecuaria. Centro Regional Tucuman-Santiago del Estero. Estación Experimental Agropecuaria Famaillá; ArgentinaFil: Posse Beaulieu, Gabriela. Instituto Nacional de Tecnología Agropecuaria. Centro de Investigación de Recursos Naturales. Instituto de Clima y Agua; ArgentinaFil: Acreche, Martin Moises. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Instituto Nacional de Tecnología Agropecuaria. Centro Regional Salta. Estación Experimental Agropecuaria Salta; Argentin

Increases in nitrogen use efficiency decrease nitrous oxide emissions but can penalize yield in sugarcane

Nitrogen (N) fertilization strategies focused on increasing nitrogen use efficiency (NUE) and decreasing nitrous oxide (N2O) emissions are important for sustainable crop production. In sugarcane, however, a joint assessment of NUE, N2O emissions and yield is still required. We aimed to establish, in a subtropical sugarcane cropping system, if variations in NUE (by decreasing rates or changing formulations of N fertilization) allow decreasing N2O emissions and, to what extent, yield is penalized. Four fertilization treatments were used: without fertilizer, with low and high urea fertilization (55 and 110 kg N ha−1) and with ammonium nitrate fertilization (110 kg N ha−1). There was a significant negative relationship between N2O emissions and NUE. At high N rates (110 kgN ha−1) ammonium nitrate produced 37% higher cumulative N2O emissions and 13 and 12% lower NUE and cane yield, respectively, than urea. The highest N2O emissions of the ammonium nitrate treatment occurred within 48 hs after N fertilization and were mainly associated with the direct addition of nitrate (NO3−–N). Results showed that, for the environmental conditions of Tucuman (Argentina), NUE above 160 kg of cane per kg of N available in soil penalized cane yield, whereas NUE below 140 kg of cane per kg of N available in soil penalized N2O emission abatement.Fil: Chalco Vera, Jorge Elías. Instituto Nacional de Tecnología Agropecuaria. Centro Regional Salta. Estación Experimental Agropecuaria Salta; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Salta; ArgentinaFil: Portocarrero, Rocio de Los Angeles. Instituto Nacional de Tecnología Agropecuaria. Centro Regional Tucuman-Santiago del Estero. Estación Experimental Agropecuaria Famaillá; Argentina. Universidad Nacional de Tucumán. Facultad de Agronomía y Zootecnia; ArgentinaFil: Piñeiro, Gervasio. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Parque Centenario. Instituto de Investigaciones Fisiológicas y Ecológicas Vinculadas a la Agricultura. Universidad de Buenos Aires. Facultad de Agronomía. Instituto de Investigaciones Fisiológicas y Ecológicas Vinculadas a la Agricultura; ArgentinaFil: Acreche, Martin Moises. Instituto Nacional de Tecnología Agropecuaria. Centro Regional Salta-Jujuy. Estación Experimental Agropecuaria Salta; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Salta; Argentin

Greenhouse gas emissions from green-harvested sugarcane with and without postharvest burning in Tucumán, Argentina

Concentrations of greenhouse gases (GHG) in the atmosphere are increasing due to anthropogenic actions, and agriculture is one of the most important contributors. This study quantified GHG emissions from greencane harvested sugarcane with and without post-harvest burning in Tucuma´n (Argentina). A field trial was conducted in Tucuma´n during the 2011/2012 season using a randomised complete-block design with four replications. Treatments were: (a) harvest without sugarcane burning (neither before nor after), and (b) harvest with trash burnt after harvest. The method used to capture gases (CO2, CH4 and N2O) in the crop cycle was based on closed-vented chambers, while quantification was by gas chromatography. There were significant emission rates of CO2 and N2O during the sugarcane cycle in Tucuma´n, but no evidence of CH4 emissions or uptakes. N2O and CO2 emission rates were higher in the no-burning treatment than in the burnt, but only in part of the crop cycle. The former is apparently associated with the application of nitrogen fertiliser, while the higher CO2 emissions seem to be associated with trash retention. There were no significant correlations between environmental factors and emission rates. Although these results seem pessimistic, in the context of an entire crop GHG balance (including the emissions due to burning before or after harvest) green-cane harvesting without burning could effectively lead to a reduction of total GHG emissions during the crop cycle.Fil: Acreche, Martin Moises. Instituto Nacional de Tecnología Agropecuaria. Centro Regional Tucumán-Santiago del Estero. Estación Experimental Agropecuaria Famaillá; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Tucumán; ArgentinaFil: Portocarrero, R.. Instituto Nacional de Tecnología Agropecuaria. Centro Regional Tucumán-Santiago del Estero. Estación Experimental Agropecuaria Famaillá; ArgentinaFil: Chalco Vera, Jorge Elías. Instituto Nacional de Tecnología Agropecuaria. Centro Regional Tucumán-Santiago del Estero. Estación Experimental Agropecuaria Famaillá; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Tucumán; ArgentinaFil: Danert, C.. Universidad Nacional de Tucumán. Facultad de Agronomía y Zootecnia; ArgentinaFil: Valeiro, A. H.. Instituto Nacional de Tecnología Agropecuaria. Centro Regional Tucumán-Santiago del Estero. Estación Experimental Agropecuaria Famaillá; Argentin

Could the ecophysiological basis of sugarcane be of help in improving sugar yield gains?

Sugar yield (SY) gains worldwide have been slowing down since the 1980s. This study aimed to identify how this trend could be reversed by exploring the ecophysiological basis associated with yield increments. Nitrogen, water and radiation use efficiencies were explored. Thirteen cultivars were grown during three consecutive cycles at Tucumán, Argentina. Cane yield (CY), sugar content (SC), SY, average-stem-weight (ASW), nitrogen-use-efficiency (NUE) and wateruse-efficiency (WUE) increased linearly with the year of release of the cultivars. Sugar yield was associated with CY, SC, ASW, NUE and WUE (r>0.65; P0.81; P<0.01). Stem number at harvest was not increased by breeding and was not related to SY and CY. This could be because breeding did not modify the dynamic of generation and mortality of stems. However, breeding modified the canopy architecture of the crop. This was associated with increases in the amount of radiation intercepted by the crop during its cycle; modern cultivars had higher maximum interception and needed fewer days to reach maximum interception than older cultivars. However, sugarcane breeding did not increase the radiation-use-efficiency. In summary, using ecophysiological tools could help breeders to improve SY.Fil: Acreche, Martin Moises. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Salta; Argentina. Instituto Nacional de Tecnología Agropecuaria. Centro Regional Salta-Jujuy. Estación Experimental Agropecuaria Salta; ArgentinaFil: Chalco Vera, Jorge Elías. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Salta; Argentina. Instituto Nacional de Tecnología Agropecuaria. Centro Regional Salta-Jujuy. Estación Experimental Agropecuaria Salta; ArgentinaFil: Saez, Julio Víctor. Instituto Nacional de Tecnología Agropecuaria. Centro Regional Tucuman-Santiago del Estero. Estación Experimental Agropecuaria Famaillá; ArgentinaFil: Martínez Calsina, Luciana. Instituto Nacional de Tecnología Agropecuaria. Centro Regional Tucuman-Santiago del Estero. Estación Experimental Agropecuaria Famaillá; ArgentinaFil: Erazzú, Luis Ernesto. Instituto Nacional de Tecnología Agropecuaria. Centro Regional Tucuman-Santiago del Estero. Estación Experimental Agropecuaria Famaillá; Argentina30th Congress of the International Society of Sugar Cane TechnologistsTucumánArgentinaInternational Society of Sugar Cane Technologist

Long-term vinasse application enhanced the initial dissipation of atrazine and ametryn in a sugarcane field in Tucumán, Argentina

The production of sugarcane bioethanol generates large volumes of vinasse, an effluent whose final disposal can produce an environmental impact that is of concern. The long-term disposal of vinasse in sugarcane fields could challenge crop management, such as the performance of traditional herbicides, by changing soil properties. This study aimed to evaluate the effect of long-term vinasse application on the field and the dissipation of atrazine and ametryn herbicides in a subtropical sugarcane agroecosystem, and to discuss the potential processes involved in it. Vinasse affected soil properties by increasing pH (12%), electrical conductivity (160%), and soil organic carbon (25%) at 0–10 cm depth of soil. Differences in the herbicide calculated sorption coefficient (Kd) varied according to the pedotransfer function applied and the herbicide type (atrazine or ametryn). During the first seven days after herbicide application, the soil underwent long-term vinasse application and increased atrazine and ametryn dissipation 45% and 33%, respectively, compared with the conventional fertilization scheme (control). The Pesticide Root Zone Model revealed that dissipation was mediated mainly by the degradation process rather than transport or other processes. The long-term application of vinasse in a typical sugarcane field of Tucumán, Argentina decreased the potential groundwater pollution of triazines and, adversely, reduced their bioavailability for weed control. For this, the present study presents original information about how long-term treatment with vinasse may require an adaptation of conventional management practices such as the application of herbicides in Argentina and other sugarcane-producing regions.EEA FamailláFil: Portocarrero, Rocio. Instituto Nacional de Tecnología Agropecuaria (INTA). Estación Experimental Agropecuaria Famaillá; ArgentinaFil: Portocarrero, Rocio. Universidad Nacional de Tucumán. Facultad de Agronomía y Zootecnia; ArgentinaFil: Chalco Vera, Jorge Elias. Instituto Nacional de Tecnología Agropecuaria (INTA). Estación Experimental Agropecuaria Salta; Argentina.Fil: Chalco Vera, Jorge Elias. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Vallejo, Juan Inosencio. Instituto Nacional de Tecnología Agropecuaria (INTA). Instituto de Investigación Animal del Chaco Semiárido; Argentina.Fil: De Gerónimo, Eduardo. Instituto Nacional de Tecnología Agropecuaria (INTA). Estación Experimental Agropecuaria Balcarce; ArgentinaFil: De Gerónimo, Eduardo. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Costa, José Luis. Instituto Nacional de Tecnología Agropecuaria (INTA). Estación Experimental Agropecuaria Balcarce; ArgentinaFil: Aparicio, Virginia Carolina. Instituto Nacional de Tecnología Agropecuaria (INTA). Estación Experimental Agropecuaria Balcarce; ArgentinaFil: Aparicio, Virginia Carolina. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentin