Biossegurança da proteína Cry1Ac, sintetizada pelo algodão geneticamente modificado, em abelhas indígenas sem ferrão e africanizadas

• Autor(a) principal: Siqueira, Maria Augusta Lima
• Data de Publicação: 2008
• Tipo de documento: Tese
• Idioma: por
• Título da fonte: LOCUS Repositório Institucional da UFV
• Texto Completo: http://locus.ufv.br/handle/123456789/851
• topic: Biossegurança; Apis mellifera; Trigona spinipes; Algodão; Biosafety; Apis mellifera; Trigona spinipes; Cotton; CNPQ::CIENCIAS BIOLOGICAS::ZOOLOGIA

Genetic engineering techniques offer opportunities for the developement of insect-resistant plants due to the synthesis of entomotoxical proteins by plants. To evaluate the biosafety of GM cotton in relation to pollinators, bioassay methods were developed for rearing larvae of Trigona spinipes and Apis mellifera, bees commonly found in cotton flowers in Brazil, using Cry1Ac protein as a model. Protocols were developed for rearing T. spinipes larvae under laboratory controlled conditions, using natural bee food. Similar methods were used for rearing larvae of A. mellifera treated with artificial diet. Bioassays were developed to expose the bees of both species to three treatments, with five replicates (40 bees/replicate): (i) pure bee food (control); (ii) bee food + sterile water; (3) bee food + sterile water + Cry1Ac. Mortality and development of the bees were monitored daily. Body mass, head width and intertegular span of newly-emerged bees were recorded for the three treatments. Brood rearing methods were successful for T. spinipes larvae (91% survival in the control). Rearing of A. mellifera, however, resulted in high mortality in the three treatments. None of the parameters parameters analyzed were statistically different among the treatments for both species. Methodologies used for rearing workers of T. spinipes and A. mellifera were adequated for toxicological studies with entomotoxical proteins on these bees. Survival, size and development time of T. spinipes and A. mellifera were not altered by the ingestion of Cry1Ac, but studies with larvae that will develop into queens are still necessary.