Gene flow of transgenes into non-target populations is an important biosafety concern. The case of genetically modified (GM) maize in Mexico has been of particular interest because of the country’s status as center of origin and landrace diversity. In contrast to maize in the U.S. and Europe, Mexican landraces form part of an evolving metapopulation in which new genes are subject to evolutionary processes of drift, gene flow and selection. Although these processes are affected by seed management and particularly seed flow, there has been little study into the population genetics of transgenes under traditional seed management. Here, we combine recently compiled data on seed management practices with a spatially explicit population genetic model to evaluate the importance of seed flow as a determinant of the long-term fate of transgenes in traditional seed systems. Seed flow between farmers leads to a much wider diffusion of transgenes than expected by pollen movement alone, but a predominance of seed replacement over seed mixing lowers the probability of detection due to a relative lack of homogenization in spatial frequencies. We find that in spite of the spatial complexities of the modeled system, persistence probabilities under positive selection are estimated quite well by existing theory. Our results have important implications concerning the feasibility of long term transgene monitoring and control in traditional seed systems.
Este artículo publicado en la revista Internacional, Molecular Ecology, confirma la presencia de transgenes en maíces nativos de Oaxaca y muestra modelos de simulación sobre la dinámica de dispersión de transgenes en poblaciones de maices nativos en México. Contribuye a la discusión sobre métodos de monitoreo,tanto en su componente molecular, como de muestreo.
Cecilio Mota Cruz Fundación
Semillas de Vida, AC
El calentamiento global o "cambio climático" es el mayor reto ambiental que enfrentaremos en este siglo. Sus impactos ya se están verificando y, de no tomar medidas preventivas de inmediato, serán mucho más severos.
With the rapid growth of biofuel production and consumption, and the proliferation of policy decisions supporting this expansion, concerns about the biofuel sector’s environmental and social impacts are increasing. Consequently, a range of actors – among them governments, multilateral institutions, nongovernmental organisations and multistakeholder industry groups – have created sustainability frameworks, some mandatory, others voluntary. This report examines how the most developed sustainability frameworks for feedstock production (including biofuels) address key environmental issues. It identifies critical gaps in these frameworks and proposes areas for improvement. The frameworks analysed are the European Union Renewable Energy Directive (EU RED), Roundtable on Sustainable Biofuels (RSB), Roundtable on Sustainable Palm Oil (RSPO), Round Table on Responsible Soy Association (RTRS), Better Sugarcane Initiative (BSI) and the Forest Stewardship Council (FSC).
In this article, we attempt to find the spatial relations between deforestation and biofuel production at global level by analyzing available global deforestation and biofuels data, and find that, for a variety of reasons relating to data availability and its characteristics, and the way biofuels are produced, this task is extremely difficult if not virtually impossible. Then we bring down the scale of the analysis to the case study level and provide a detailed methodology for analyzing the spatial relation between deforestation and biofuel development. We argue that this multi-scale approach, based on systematic sampling at the case study level would help to better understand the relation between biofuels and deforestation. Given the fact that biofuels are a highly contested approach to reduction of global carbon emissions, and that different lobbies in this debate are making claims that deforestation is, or is not, occurring as a result of the expansion of biofuel production, clarity on the methodological difficulties of making statements of this kind, at least in a global spatial analysis, may help avoid false conclusions being promulgated in the future.
The relationship between biofuel development and tropical deforestation is complex. It is difficult to detect direct links and to quantify these at the global level, due to limited data availability. These limitations include: the lack of time series data on deforestation at sufficient resolution on the global scale; the lack of information on the geographical location of biofuel cultivation areas; much of the deforestation related to biofuel cultivation being indirect through displacement of other agriculture; much of the biofuel cultivation being very recent; and, that many biofuel feedstocks are multipurpose (biofuels often represent only a small proportion of larger food and fodder production systems).
Mexico has recently taken significant steps towards promoting the bioenergy sector. Adoption of bioenergy is perceived as an opportunity to develop alternatives to fossil fuels, to foster economic development and to meet international commitments to reduce greenhouse gases. However, such opportunities are accompanied by concerns such as the effect of biofuel production on deforestation rates – concerns that may be addressed through policy instruments and proper program design. Therefore, this country report contains an analysis of the legal and institutional frameworks related to Mexico’s bioenergy sector.
A forester’s perspective
Enrique Riegelhaupt and Teresita Arias Chalico
“BEBIDAS ALCOHÓLICAS - BEBIDAS ALCOHÓLICAS ELABORADAS A PARTIR DE AGAVÁCEAS - ESPECIFICACIONES, MÉTODOS DE PRUEBA E INFORMACIÓN COMERCIAL”.
"BEBIDAS ALCOHÓLICAS, BEBIDAS ALCOHÓLICAS ELABORADAS A PARTIR DE AGAVÁCEAS. ESPECIFICACIONES, MÉTODOS DE PRUEBA E INFORMACIÓN COMERCIAL".
Rising agricultural prices, combined with growing import dependence, have driven Mexico’s food import bill over $20 billion per year and increased its agricultural trade deficit. Mexico imports one-third of its maize, overwhelmingly from the United States, but three million producers grow most of the country’s white maize, which is used primarily for tortillas and many other pluricultural products for human consumption. Yield gaps are large among the country’s small to medium-scale maize farmers, with productivity estimated at just 57% of potential. To what extent could Mexico close this yield gap, using proven technologies currently employed in the country, to regain its lost self-sufficiency in maize? A comprehensive review of the literature highlights the potential for achieving that goal. With a new government coming to power in Mexico, policy options are examined, identifying those most likely to increase both maize productivity and sustainable resource use while reducing import dependence. With climate change likely to constrain input-intensive agricultural productivity growth, these involve an emphasis on farmer-led extension services, the promotion of sustainable agricultural practices, and improved water management, including expanded irrigation.
A new study shows that glyphosate herbicide (e.g. Roundup) enhances the growth of aflatoxin-producing fungi.
GM Bt crops have long been touted as a solution to the problem of aflatoxins in grains. Aflatoxins are toxic and in some cases carcinogenic to animals and humans. The fungi that produce aflatoxins also cause plant diseases.
Cultivation-independent establishment of genetically engineered plants in natural populations: current evidence and implications for EU regulation
Andreas Bauer-Panskus1, Broder Breckling23, Sylvia Hamberger4 and Christoph Then5*
* Corresponding author: Christoph Then email@example.com
1 epigen, Frohschammerstr. 14, Munich 80807, Germany
2 Landscape Ecology, University of Vechta, Driverstrasse 22, Vechta 49377, Germany
3 UFT Centre of Environmental Research and Sustainable Technology, University of Bremen, Bibliothekstrasse 1, Bremen 28359, Germany
4 Gesellschaft für Ökologische Forschung, Frohschammerstr. 14, Munich 80807, Germany
5 Testbiotech, Frohschammerstr. 14, Munich 80807, Germany
Laboratory Rodent Diets Contain Toxic Levels of Environmental Contaminants: Implications for Regulatory Tests
Robin Mesnage , Nicolas Defarge , Louis-Marie Rocque, Joël Spiroux de Vendômois, Gilles-Eric Séralin
Economic and environmental impacts of production intensification in agriculture: comparing transgenic, conventional, and agroecological maize crops
Adinor José Capellesso, Ademir Antonio Cazella, Abdon Luiz Schmitt Filho, Joshua Farley & Diego Albino Martins
SUPLEMENTO "EL JAROCHO CUANTICO"
Número especial de aniversario
Monografía sobre las características toxicológicas de este herbicida que los OGM usan de forma exclusiva.
Pervasive presence of transgenes and glyphosate in maize-derived food in Mexico
Presencia masiva de transgenes y del herbicida glifosato en alimentos derivados de maíz en México
E. González-Ortega, A. Piñeyro-Nelson, E. Gómez-Hernández, E. Monterrubio-Vázquez, M. Arleo, J. Dávila-Velderrain, C. Martínez-Debat & E.R. Álvarez-Buylla
Conflictos socioambientales, resistencias ciudadanas y violencia neoliberal en México
Víctor M. Toledo
Socio-environmental Conflicts in Mexico
Víctor M. Toledo
Mariana Ortega Breña