Bt toxin is not taken up from soil or hydroponic culture by corn, carrot, radish, or turnip
Authors: Saxena, D., Stotzky, G.
Journal, Volume, Year: Plant and Soil, volume 239:165-172, 2002
The rhizosphere soil of Bt and isoline corn was collected and carrot, radish, and turnip were grown in the soil. Carrot, isoline corn, and radish were also grown in soil amended with Bt corn biomass. Additionally, Bt corn was grown hydroponically for 15 days and then non-Bt was grown in the same media for 7 and 15 days. Finally, plants were grown in soil amended with purified Bt protein for 30, 60, and 90 days. The analytical methods utilized were Quickstix ELISA and bioassay. No toxin uptake was observed in any of the experiments. Soils amended with biomass were positive for Bt presence (using both ELISA and larvicidal assay) after 120 and 180 days.
The study used both plant-produced and microbially-produced material, for a good comparison. The results of finding presence of Bt in rhizosphere soil 180 days after removal is very different from other fate studies.