Publication: Riesgos y beneficios del cultivo en España de maíz Bt (MON810) resistente a insectos
Loading...
Files
Official URL
Full text at PDC
Publication Date
2016-03-14
Authors
Advisors (or tutors)
Editors
Journal Title
Journal ISSN
Volume Title
Publisher
Universidad Complutense de Madrid
Citations
Exportar
Abstract
El uso de plantas genéticamente modificadas (GM) resistentes a insectos que expresan toxinas Cry de Bacillus thuringiensis ofrece un control altamente efectivo sobre plagas de gran importancia económica. Actualmente, la única planta GM resistente a insectos que se cultiva comercialmente en Europa es el maíz MON810 que expresa la toxina Cry1Ab (maíz Bt), activa frente a los taladros del maíz Ostrinia nubilalis (Hübner) (Lepidoptera: Crambidae) y Sesamia nonagrioides (Lefèbvre) (Lepidoptera: Noctuidae). Los daños de ambas especies son producidos por las larvas, que tienen un comportamiento endófito, es decir, penetran en el interior de la caña de la planta y se alimentan de su médula. Por este motivo, el maíz Bt es el método de control que se ha mostrado más eficaz en zonas con alta incidencia de dichas plagas. España es el único país de la UE que ha adoptado de forma significativa este cultivo, habiéndose sembrado en 2014 más de 130.000 ha, lo que representó el 30% del total de maíz. La incorporación del maíz Bt a la agricultura ha suscitado una gran controversia en Europa debido, entre otros motivos, a los posibles efectos que la liberación a gran escala de estas plantas puede producir sobre el medio ambiente. A pesar que el maíz Bt controla de manera específica a los taladros, los artrópodos asociados temporal y/o espacialmente al agroecosistema hacia los que no va dirigido este control (artrópodos nodiana), pueden estar expuestos a la toxina, y por tanto verse afectados por la misma. Hasta el momento se han realizado numerosos estudios de campo y de laboratorio con artrópodos de distintos grupos funcionales presentes en el cultivo del maíz para evaluar la toxicidad de la proteína Cry1Ab sobre ellos, así como el nivel de exposición al que pueden estar sometidos. Sin embargo, a pesar de toda la información recabada, aún quedan aspectos relevantes por conocer acerca de los efectos del cultivo del maíz Bt sobre algunos artrópodos no-diana que se encuentran en las partes aéreas de la planta y sobre los microartrópodos que habitan en el suelo, así como de su exposición a la toxina insecticida en el campo. Como no es posible llevar a cabo evaluaciones de riesgo ambiental de plantas GM para todas las especies presentes en un agroecosistema, se ha propuesto la utilización de especies indicadoras, sensibles a cambios en el medio ambiente o importantes por su papel ecológico, que actuarían como representantes de una comunidad de artrópodos determinada. En general, la selección de estas especies se basa en diversos criterios como su función ecológica, distribución geográfica, la posible exposición a la toxina, la facilidad para la identificación taxonómica en campo, el manejo en el laboratorio o la importancia económica...
The use of insect-resistant genetically modified (GM) crops which express insecticidal Cry proteins from Bacillus thuringiensis is an effective method to control pests of major economic importance. Nowadays, the only insect-resistant GM plants commercially cultivated in the EU are those maize varieties derived from the event MON810, engineered to express the Cry1Ab insecticidal protein (Bt maize). This toxin efficiently control two key pests: the Mediterranean corn borer, Sesamia nonagrioides (Lefèbvre) (Lepidoptera: Noctuidae) and the European corn borer, Ostrinia nubilalis (Hübner) (Lepidoptera: Crambidae). Immature stages of both species have endophytic behaviour, being the main damage caused by the stalk tunneling of larger larvae. As a consequence, Bt maize has shown high efficacy to control these pests, especially in areas where they are in high densities. Among the EU, Spain is the member state with the highest adoption rate of Bt maize, presenting more than 130.000 hectares in 2014 (representing the 30% of the total maize cultivated in the country). The extended use of Bt maize into agriculture has raised controversy in Europe, mainly due to the potential negative effects that the extended spread of these GM plants could cause to the environment. Despite Bt maize is highly specific to control these two corn borers, other arthropods associated with the GM plant that are not targeted (non-target arthropods) could be exposed and negatively affected by the toxin. So far, several laboratory and field studies have assessed the toxicity of the Cry1Ab protein against different functional guilds of non-target arthropods and their exposure to the toxin. Nevertheless, there are still certain groups and aspects associated with the cultivation of Bt maize that require more research, as the effects of Bt maize on non-target arthropods inhabiting the aerial parts of the maize and on the soil microarthropod communities, as well as their exposure to the insecticidal toxin in the field. Since not all the non-target arthropods can be tested, it has been proposed the selection of a representative subset of them (referred as surrogate species) for consideration in the risk assessment of GM plants. The species selection should be performed according to different selection criteria, such as: ecological function, geographical distribution, potential exposure to the toxin, economic relevance and feasibility to be taxonomically identified in the field and to perform bioassays in the laboratory...
The use of insect-resistant genetically modified (GM) crops which express insecticidal Cry proteins from Bacillus thuringiensis is an effective method to control pests of major economic importance. Nowadays, the only insect-resistant GM plants commercially cultivated in the EU are those maize varieties derived from the event MON810, engineered to express the Cry1Ab insecticidal protein (Bt maize). This toxin efficiently control two key pests: the Mediterranean corn borer, Sesamia nonagrioides (Lefèbvre) (Lepidoptera: Noctuidae) and the European corn borer, Ostrinia nubilalis (Hübner) (Lepidoptera: Crambidae). Immature stages of both species have endophytic behaviour, being the main damage caused by the stalk tunneling of larger larvae. As a consequence, Bt maize has shown high efficacy to control these pests, especially in areas where they are in high densities. Among the EU, Spain is the member state with the highest adoption rate of Bt maize, presenting more than 130.000 hectares in 2014 (representing the 30% of the total maize cultivated in the country). The extended use of Bt maize into agriculture has raised controversy in Europe, mainly due to the potential negative effects that the extended spread of these GM plants could cause to the environment. Despite Bt maize is highly specific to control these two corn borers, other arthropods associated with the GM plant that are not targeted (non-target arthropods) could be exposed and negatively affected by the toxin. So far, several laboratory and field studies have assessed the toxicity of the Cry1Ab protein against different functional guilds of non-target arthropods and their exposure to the toxin. Nevertheless, there are still certain groups and aspects associated with the cultivation of Bt maize that require more research, as the effects of Bt maize on non-target arthropods inhabiting the aerial parts of the maize and on the soil microarthropod communities, as well as their exposure to the insecticidal toxin in the field. Since not all the non-target arthropods can be tested, it has been proposed the selection of a representative subset of them (referred as surrogate species) for consideration in the risk assessment of GM plants. The species selection should be performed according to different selection criteria, such as: ecological function, geographical distribution, potential exposure to the toxin, economic relevance and feasibility to be taxonomically identified in the field and to perform bioassays in the laboratory...
Description
Tesis inédita de la Universidad Complutense de Madrid, Facultad de Ciencias Biológicas, Departamento de Microbiología III, leída el 09-12-2015