Impacto do cultivo da soja resistente ao glyphosate sobre artrópodes e componentes de produção da cultura

• Autor(a) principal: Pereira, Jardel Lopes
• Data de Publicação: 2009
• Tipo de documento: Tese
• Idioma: por
• Título da fonte: LOCUS Repositório Institucional da UFV
• Texto Completo: http://locus.ufv.br/handle/123456789/1124
• topic: Soja; Plantas transgênicas; Glyphosate; Soybean; Transgenic crops; Glyphosate; CNPQ::CIENCIAS AGRARIAS::AGRONOMIA::FITOTECNIA

The global area planted with transgenic crops was 125 million hectares in 2008. Of this total, 53% was occupied by soybean modified for tolerance to glyphosate. The rapid acceptance of this technology is due to high efficiency, low cost and easy to implement. However, the abuse use of a broad spectrum herbicide can cause direct and indirect impacts. The direct impact is caused by the cultivation of transgenic soybean by inserting the gene for glyphosate resistance (CP4 EPSPS) from the Agrobacterium sp. strain CP4. Indirect effects may include changes in management practices of culture, mainly due to utilization of glyphosate in post-emergence of soybean. This work aimed to evaluate the impact of soybean crops resistant to glyphosate and their management with glyphosate on arthropods and components of plant yield. The experiment was conducted during the growing seasons of 2007/2008 and 2008/2009 in experimental station of Universidade Federal de Viçosa in Coimbra, Minas Gerais State, Brazil. The treatments studied were: non-GM and GM soybean with mechanical weed control; and GM soybean with one and three applications of glyphosate. Transgenic soybean, resistant to glyphosate did not affect the richness and abundance of arthropods in the canopy of plants, and the surface and inside the soil. In transgenic soybean canopy, with three applications of glyphosate, the total density of arthropods (in the second year of cultivation) and phytophagous chewer Cerotoma arcuatus (Coleoptera: Chrysomelidae) was lower than those observed in other treatments. The same occurred with the total density of arthropods on the soil surface, especially predators Achaearanea sp. (Araneae: Theridiidae), Oxypodini sp. (Coleoptera: Staphylinidae) and Solenopsis sp. (Hymenoptera: Formicidae) and detritivorous Entomobryidae (Collembola), Hypogastrura sp. (Collembola: Hypogastruridae) and Xyleborus sp. (Coleoptera: Scolytidae). Since the reverse was observed for the phytophagous sucking Bemisia tabaci (Hemiptera: Aleyrodidae), Caliothrips brasiliensis (Thysanoptera: Thripidae) and Tetranychus sp. (Acari: Tetranychidae) in the plant canopy. The application of glyphosate (one or three) reduced the densities of predator Solenopsis sp. and detritivore Hypogastrura sp. the canopy of the plant. The same occurred inside the soil, with the predators Acari: Galumnidae, Neivamyrmex sp. (Hymenoptera: Formicidae) and Solenopsis sp. and the detritivorous Entomobryidae, Hypogastrura sp. Onychiuridae. The soybean resistant to glyphosate and their management with glyphosate did not affect the components of plant yield; growth, development and crop productivity.