Crop Biotech Update

Effect of Exposure to Multiple Bt Proteins on Honey Bee Larvae

March 30, 2012

Honey bee is an important non-target organism used in environmental risk assessment of GM crops. Harmer Hendriksma of the University of Würzburg, Germany, and colleagues analyzed the reaction of honey bee larvae on exposure to three insecticidal Bacillus thuringiensis (Bt) proteins and CP4-protein conferring herbicide resistance combined in one GM maize variety. They also tested the biosafety of Galanthus nivalis agglutinin (GNA lectin), a candidate protein for pest control.

The bee larvae were subjected under worst-case exposure scenario using controlled in vitro larvae rearing. Results showed that the combination of three Bt proteins had no adverse effect on the bee larvae. On the contrary, the GNA lectin was found to be toxic for the larvae at certain levels signified by changes in the pupal weight before and after the exposure.

The researchers concluded that neither one Bt protein nor the combination thereof could bring harmful effects on honey bee larvae.

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