85 research outputs found
Intensive Soybean Management : an Integrated Systems Approach
No full textEcological intensification impacted soybean yield, biomass and N uptake. Narrow row spacing, high seeding rate, other best production practices, and balanced nutrition increased partitioning effi ciency for biomass, measured by seed harvest index
(HI), grain N, and N HI (NHI). Partial factor productivity of fertilizer (PFPf) increased when best production and fertilizer management practices were implemented in combination, with 19% and 28% increases under irrigated and dryland scenarios, respectively. An integrated approach, simultaneously considering multiple management factors in a farming system, is needed for closing exploitable yield gapsEEA OliverosFil: Balboa, Guillermo R. Kansas State University. Department of Agronomy; Estados UnidosFil: Stewart, W.M. International Plant Nutrition Institute. North American Program; Estados UnidosFil: Salvagiotti, Fernando. Instituto Nacional de Tecnología Agropecuaria (INTA). Estación Experimental Agropecuaria Oliveros. Departamento de Agronomía; ArgentinaFil: García, Fernando O. International Plant Nutrition Institute. Latin American Southern Cone; ArgentinaFil: Francisco, Eros Artur Bohac. International Plant Nutrition Institute; BrasilFil: Ciampitti, Ignacio A. Kansas State University. Department of Agronomy; Estados Unido
ASEAN Rules of Origin: Lessons and Recommendations for Best Practice
No full textRules of Origin (ROO) set the criteria in determining the nationality of a product and where a product was made. The importance of ROO has increased in the past years as more countries engage in Free Trade Agreements (FTAs) and begun treating goods differently according to where the product was made, along with trade-specific preferences or restrictions to the imported good once its origin is determined. This study is done to cull the lessons from ASEAN's experience in determining and implementing the Rules of Origin. It draws the important lessons and makes recommendations for best practice that would contribute to the cooperation and integration efforts in the region. The paper examines the various design and implementation practice in ROO regimes, focusing on RTAs where the ASEAN is involved. The paper presents findings from recent studies on the cost of ROO compliance and the FTA utilization rates. It concludes with recommendations on simplification of ROO and some reforms on administrative procedures, bringing in the development country dimension, and some general guidelines to follow to improve ROOs.Rules of Origin, Free Trade Agreements, ASEAN.
Best management systems for intensifying a maize – soybean rotation: integrating field production, plant physiology, and modeling
No full textDoctor of PhilosophyDepartment of AgronomyIgnacio A. CiampittiPotential yield (PY) is defined by the yield limited by temperature, radiation, and genetics – under no limitation on nutrients or water. The difference between PY and actual yield (AY) is defined as yield gap (YG). Management practices such as planting date, row spacing, seeding rate, fertilization program, pest, and disease control can help producers to intensify the productivity of the farming systems and consequently, close the YGs. To evaluate the impact of different management system (MS, specific combination of management practices) on closing the YG the following objectives were established: i) conduct a historical synthesis analysis to characterize shifts in soybean yields, biomass and nutrient uptake and partitioning dissecting the main physiological component related to nutrient use efficiency, seed nutrient composition and nutrient stoichiometry; ii) study the contribution of five MS for intensifying maize-soybean production systems; iii) quantify the nitrogen (N) contribution from the biological N fixation (BNF) process for soybeans under two contrasting MSs (low vs. high inputs); and iv) utilize the same contrasting input treatments to calibrate the Agricultural Production System Simulator (APSIM) for modeling a maize – soybean rotation and apply the parametrized model to estimate a long-term (1980-2016) simulation. For the first objective, main findings indicate that soybean yield increase over time was driven by an increase in biomass with a relatively small variation in harvest index, and with modern varieties producing more yield per unit of N uptake. For the second objective, field experiments demonstrated that intensification practices (narrow row spacing, increasing seeding rate and implementation of a balanced nutrition program) increased yields in both soybeans and maize under rainfed and irrigated conditions. For the third objective, to better understand the soybean N status, BNF measurements were collected during the 2015 growing season and also investigated in a greenhouse setting. The B value, N fixation when plants are fully relying on atmospheric N, changed among varieties, growth stages and plant fractions. Overall B value at R₇ (beginning of maturity) was -1.97 contrasting with the -1.70 value reported as mode according to a literature review. For the range of fixation measured in this research (average of 45-57%), utilization of a B value obtained from the scientific literature or measured in field conditions will have a reduced impact on BNF estimations. Lastly, for the last and fourth objective, the APSIM performed well in estimating yield, biomass production and total N uptake with a high model efficiency and low relative root mean square error (RRMSE). The long-term simulation helped characterize the YG for each crop and MS according to different weather patterns. The modeling approach increased the value of data collected in field experiments. Overall, this research project provided an approach to quantifying and understanding YGs in a maize-soybean rotation and the impact of different MSs on intensifying productivity. Future work can be conducted to model specific MSs to advise producers on the best management systems (BMSs) for sustainably intensifying productivity while minimizing the environmental footprint of current farming systems
A systems-level yield gap assessment of maize-soybean rotation under high- and low-management inputs in the Western US Corn Belt using APSIM
No full textQuantifying yield gaps (potential minus actual yield) and identifying management practices to close those gaps is critical for sustaining high-yielding production systems. The objectives of this study were to: 1) calibrate and validate the APSIM maize and soybean models using local field experimental data and 2) use the calibrated model to estimate and explain yield gaps in the long term as a function of management (high- vs low-input) and weather conditions (wet-warm, wet-cold, dry-warm and dry-cold years) in the western US Corn Belt. The model was calibrated and validated using in-season crop growth data from six maize-soybean rotations obtained in 2014 and 2015 in Kansas, US. Experimental data included two management systems: 1) Common Practices (CP, low-input), wide row spacing, lower seeding rate, and lack of nutrient applications (except N in maize), and 2) Intensified Practices (IP, high-input), narrow rows, high seeding rate, and balanced nutrition. Results indicated that APSIM simulated in-season crop above ground mass and nitrogen (N) dynamics as well yields with a modeling efficiency of 0.75 to 0.92 and a relative root mean square error of 18 to 31%. The simulated maize yield gap across all years was 4.2 and 2.5 Mg ha−1 for low- and high-input, respectively. Similarly, the soybean yield gap was 2.5 and 0.8 Mg ha−1. Simulation results indicated that the high-input management system had greater yield stability across all weather years. In warm-dry years, yield gaps were larger for both crops and water scenarios. Irrigation reduced yield variation in maize more than in soybean, relative to the rainfed scenario. Besides irrigation, model analysis indicated that N fertilization for maize and narrow rows for soybean were the main factors contributing to yield gains. This study provides a systems level yield gap assessment of maize and soybean cropping system in Western US Corn Belt that can initiate dialogue (both experimental and modeling activities) on finding and applying best management systems to close current yield gaps.EEA OliverosFil: Balboa, Guillermo R. Kansas State University. Department of Agronomy; Estados Unidos. Universidad Nacional de Río Cuarto; ArgentinaFil: Archontoulis, Sotirios. Iowa State University. Department of Agronomy; Estados UnidosFil: Salvagiotti, Fernando. Instituto Nacional de Tecnología Agropecuaria (INTA). Estación Experimental Agropecuaria Oliveros. Departamento de Agronomía; ArgentinaFil: García, Fernando O. International Plant Nutrition Institute. Latin American Southern Cone; ArgentinaFil: Stewart, W.M. International Plant Nutrition Institute. Great Plains Region; Estados UnidosFil: Francisco, Eros Artur Bohac. International Plant Nutrition Institute. Cerrados; BrasilFil: Vara Prasad, P.V. Kansas State University. Department of Agronomy; Estados UnidosFil: Ciampitti, Ignacio A. Kansas State University. Department of Agronomy; Estados Unido
Nutrient partitioning and stoichiometry in soybean: A synthesis-analysis
No full textOn-farm attainable soybean yields are primarily limited by nutrient and water supply. High-yielding soybeans is related to high nutrient uptake. A proposed theoretical framework underpinning yield formation includes plant nitrogen (N) uptake, N harvest index (NHI), and N seed concentration (%Nseeds). The objectives of this study were focused on (i) investigating the effect of NHI and %Nseed on yield-to-uptake relation for N, and (ii) analyzing dry mass and N partitioning and extending this analysis to phosphorous (P) and potassium (K) uptake and (iii) studying the influence of specific seed:stover ratios on the relationship of N with P, and K uptake. Metadata on yield, nutrient uptake and specific-organ nutrient concentration (%nutrient) was summarized from experiments located in three different environments: Indiana, Kansas (both US), and Argentina (herein termed as IN, KS, and ARG, respectively). The main outcomes from this research were: 1) the yield-to-uptake relation for N was primarily explained by NHI; 2) the algebraic model proposed by Sinclair (1998), that includes each specific-organ %nutrient explained consistently nutrient (N, P or K) HI as a function of HI with different trend, and 3) plant nutrient ratios were primarily governed by vegetative %nutrient (stover fraction), acting as a nutrient reservoir or supply depending on the demand of nutrient in the seed. Further research on the nutrient and biomass partitioning should focus on examining the NHI:HI relationship under varying genotype x environment x management interaction.EEA OliverosFil: Tamagno, S. Kansas State University. Department of Agronomy; Estados UnidosFil: Balboa, Guillermo R. Kansas State University. Department of Agronomy; Estados UnidosFil: Assefa, Y. Kansas State University. Department of Agronomy; Estados UnidosFil: Kovács, P. Purdue University. Department of Agronomy; Estados UnidosFil: Casteel, S.N. Purdue University. Department of Agronomy; Estados UnidosFil: Salvagiotti, Fernando. Instituto Nacional de Tecnología Agropecuaria (INTA). Estación Experimental Agropecuaria Oliveros. Departamento de Agronomía; ArgentinaFil: García, Fernando O. International Plant Nutrition Institute. Latin American Southern Cone; ArgentinaFil: Stewart, W.M. International Plant Nutrition Institute. Great Plains Region; Estados UnidosFil: Ciampitti, Ignacio A. Kansas State University. Department of Agronomy; Estados Unido
La influencia de la cobertura de seguridad social como factor de dignificación del campesino en la población de Balboa Risaralda para el año 2023
No full textEste artículo pretende visualizar las políticas públicas implementadas sobre la cobertura y acceso a la seguridad social para los campesinos colombianos, dando una mirada crítica sobre su forma de aplicación y la eficacia en el terreno. Para ello se realizó una revisión documental de jurisprudencia de la Corte Constitucional, sobre la protección que debe garantizar el Estado al campesinado, y se examinaron datos oficiales relacionados con la población campesina del municipio de Balboa y su vinculación al sistema de seguridad social. Se parte del reconocimiento del campesinado colombiano como sujeto de especial protección constitucional, enmarcado en el acto legislativo 01 de 2023. Se concluye que las políticas públicas desarrolladas por el gobierno nacional no son efectivas en la protección material de los derechos fundamentales de los campesinos, además la situación de vulnerabilidad se agrava cuando se evidencia que en la muestra poblacional que para el presente caso fue el municipio de Balboa, el 70% de la población campesina no cuenta con afiliación al sistema de seguridad social.Universidad Libre Seccional Pereira -- Facultad de Derecho, Ciencias Políticas y Sociales -- Derech
Shifts in Soybean Yield, Nutrient Uptake, and Nutrient Stoichiometry: A Historical Synthesis-Analysis
No full textMechanisms of Rapid Adaptation to Environmental Stressors in Phytoplankton
No full textThis is an open-access article distributed under the terms of the Creative Commons Attribution License, which
permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.In the current scenario of global change, the impact of anthropogenic stressors is affecting the aquatic ecosystems, especially essential microorganisms such as phytoplankton, driving toward a biodiversity crisis. Classic ecotoxicology studies, focused on the immediate tolerance to pollution, have provide an over simplistic understanding of the long time impact of pollutants on phytoplankton (because of the usual misconception that evolutionary changes can only take place at long-term), inadequate to enable a suitable environmental risk assessment (ERA). Currently, concepts such as predictive ecology and integrating strategies are rising rapidly in prominence with regard to forecasting phytoplankton response to human impact. This review compiles the state of the art of multigenerational and evolutionary experimental studies and the mechanisms that trigger rapid adaptation in phytoplankton to anthropogenic stressors, highlighting the importance of ecology and evolution. Ecological realisms is one of the challenging parts of the stressors hazard, considering the broad phytoplankton diversity and the multifactorial character of the natural ambiances. Field and community experiments contribute to a better discerning of ecology interactions and network relations. Moreover, laboratory experiments exploring evolutionary mechanisms that allow rapid adaptation to contaminants (e.g., fluctuation analysis or ratchet procedures) have proven to be useful linking concentration of pollutants and adaptation strategy. When environmental change exceeds the range of variation that can be coped with by organisms through plasticity, selection processes may occur and evolutionary dynamics take place. Ecology and evolution are necessary to enhance the ERA knowledge and novel experiments may well emerge from the when contemplated as whole.Supported by the Spanish Secretaría de Estado de Investigación, Desarrollo e Innovación (Grant CTM 2012-34757 and Grant CTM 2013-44366-R) and Junta de Andalucía project RNM-04744.Peer reviewe
Income Distribution and Poverty in a CGE Framework: A Proposed Methodology
No full textThe paper discusses methodologies addressing income distribution and poverty in a Computable General Equilibrium (CGE) model framework, by describing how to link CGE results with household survey data to analyze income distribution and poverty implications. The most basic approach is simply to fit the household income/expenditure to the survey data by suitable parametric distribution functions. The post-simulation poverty indices can be estimated by either assuming that the income of each individual household within the group moves proportionally with the group's mean income, or by our proposed elasticity method. In our proposed method, we use the elasticity estimated from existing surveys to calculate the change in expenditure of each subgroup category in response to change in the household category's mean consumption, supplied by the core model's simulation, to derive post-simulation poverty indices. Our approach may better capture intra-group income distribution of households and moderate gains or losses in welfare from economic growths.Computable General Equilibrium, Income Distribution, Poverty.
Relacion Entre La Densidad Óptima Agronomica Y El Número De Granos Por Planta En Maíz (Zea Maysl.)
No full textThe density of sowing (D) is one of the main management practices that influences the yield (Y) of corn. There exists a density value in which the yield is maximum (OPD), depending on the environment, the genotype and its interaction. The objectives of this project were: i-To determine the OPD for two corn genotypes in different productive environments; ii- Analyze the relationship between the number of kernel fixed per plant (KNP) and its plant growing rate (PGR) to different environments and genotypes iii- Determine the KNP that is related to the OPD for two corn genotypes. Three experiments were carried out in different locations (L) of Córdoba (Argentina) during 2013/14, comparing 2 genotypes (G) in 2 management zones (MZ). The statistical design was random blocks, with a factorial arrangement of subdivided plots, with L, MZ and G being the primary, secondary and tertiary factors, respectively. In addition, 5 D were planted to obtain the relationships that estimate OPD, PGR, KNP and Y. The results indicate that OPD was affected by L; the relationship between PGR and KNP was not modified by the environment, but by G. The PGR coincident with the OPD was modified by the G interaction: L. The OPD the PGR was between 2.74 to 4.81 g d -1 , which were associated with the NGP that varied only between 509 and 603 grains p-1
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