Abstract: Maize DR 12-5 expessing a fused protein Cry1Ab/Cry2Aj is a genetically modified (GM) event that has been approved for preproduction field testing in China. The ecologically and economic important honey bee (Apis mellifera) is a primary non-target arthropod species in environmental risk assessment (ERA) of GM plants. When GM insect resistant plants are planted in field, pollinators may be exposed to the toxin proteins via ingestion of GM pollen. To assess the potential effect of the DR 12-5 to A. mellifera, a laboratory bioassay was conducted using the DR 12-5 pollen and purified Cry1Ab toxin. The results showed that consumption of the DR12-5 pollen or purified Cry1Ab toxin led to detection of low levels of Cry1Ab toxin in the midgut of A. mellifera adults. Neither the DR 12-5 pollen nor 8 μg·mL^-1 purified Cry1Ab toxin showed an adverse effect on the survival rate of A. mellifera adult. In contrast, feeding with 300 mg·L^-1 imidacloprid caused significant toxic effects. These results indicated the minimal risk for potential negative effects on A. mellifera by exposure to the GM maize DR 12-5 or Cry1Ab toxin.

Key words: Apis mellifera, genetically modified (GM) maize DR 12-5, Cry1Ab, pollen