Biotech Updates

Meta-analysis: Bt Maize No Effect on 26 NTO in Spain

August 7, 2013

Bt maize has been planted in Europe since 1998. EU and Spanish regulations require laboratory and field trials to analyze possible risks of GM crops on non-target organisms (NTO). Several field trials were conducted in Spain to measure the effects of Bt maize on 26 arthropod taxa and literature records of these trials showed that the GM had no effect on the non-target organisms.

Universitat de Lleida scientists conducted a meta-analysis combining the results of 13 independent field trials conducted in Spain to improve the statistical power of the analysis. Compared with the single trial analysis, the meta-analysis showed increased detectability of treatment effects for most of the taxa regardless of the sampling technique. Of the 26 arthropod taxa studied, only three had poorer detectability in the meta-analysis than the best recorded in the 13 single trials. Based on the findings of the meta-analysis, Bt maize indeed had no effect on the most common herbivore, predatory, and parasitoid arthropods present in the maize ecosystems of Spain.

Read the abstract at