Effect of two commercial formulations of Bacillus thuringiensis subsp. kurstaki (Dipel 8L and Dipel 8AF) on the collembolan species Folsomia candida in a soil microcosm study
Authors: Addison, J.A., Holmes, S.B.
Journal, Volume, Year: Bulletin of Environmental Contamination and Toxicology, volume 55:771-778, 1995
Simple microcosms were used to determine the effects of Dipel�8L and 8AF (containing Btk) on the collembolan Folsomia candida. In control microcosms and microcosms treated with Dipel�8AF, collembola populations increased rapidly. However, in microcosms treated with Dipel�8L, populations remained low throughout the experiment. Because collembolan populations were not affected by unformulated preparations of Btk or the aqueous formulation (Dipel�8AF), it was concluded that the oil-based formulation (Dipel�8L), rather than Btk itself, was responsible for reduction in collembolan populations.
This study suggests that different formulations can be toxic to collembola (e.g., aqueous vs. oil based formulations). This paper did not use Bt from transgenic plants.