According to a study conducted by Sebastian Höss of the Institute for Biodiversity in Regensburg, Germany, soil-dwelling nematodes are unaffected by a certain genetically modified Bacillus thuringiensis maize cultivar (MON89034xMON88017) containing three different Bt proteins.

The nematodes, which are essential to the soil nutrient cycle, showed a negative reaction only to levels of Bt proteins far higher than would be found in the soil of a typical Bt maize field, said the study. Practical trials were conducted over three years to determine whether the nematode communities found in the fields of Bt maize were any different from those found in conventional maize fields, with the results that the Bt maize being tested had no impact on the nematode communities.