The objective of this work was to assess the methods for detection of glyphosate tolerance soybean seeds and the gene flow from a genetically modified soybean cultivar to a conventional one, in Viçosa and Florestal, MG, Brazil. In order to assess the method for detection, a comparative experiment was conduct among five bioassays, from which the germination test in moistened substrate with glyphosate solution was outstanding. The experiment of gene flow was installed in field, in the concentric squares design. In the center, the glyphosate-tolerant cultivar (pollen source) was planted. Around it, the sensitive cultivar (pollen receptor) was sowed. In the stage R8, seeds of lateral of the squares were harvested, in various distances from the pollen source: 0.5, 1, 2, 4 and 8 m. Samples of 900 seeds by row were evaluated, using the germination test in moistened substrate with a solution of glyphosate at 0.06%. Glyphosate-tolerant seedlings indicated cross-pollination. The largest hybridization rates - 1.27% in Florestal, and 0.25% in Viçosa - ocurred at 0.5 m distance between source and pollen receiver, and these rates reached zero at 2.26 and 1.16 m distances, in Florestal and Viçosa, respectively.
Glycine max; cross-pollination; genetically modified organism
