Abstract:Bt (Bacillus thuringiensis) toxins produced in insect-resistant transgenic Bt crops can enter soils in the forms of plant residues, root exudates and pollens, posing potential risks to beneficial organisms in the soil. Active Bt toxins may be bound to certain types of soil and persist there for a long period of time. In the present study, seasonal expression patterns of Bt cry1Ab in plant tissues of Bt rice were observed, and then by burying the plant tissues highly expressing Cry1Ab into soils, degradation...