Bt toxin gene has been cloned from the bacteria and been expressed in plants to provide resistance to insects without the need for insecticides and creates a bio-pesticide. It is produced by Bacillus thuringiensis. Examples are - Bt cotton, rice, tomato, potato, soyabean etc.
Specific Bt toxin genes were isolated from Baciilus thuringiensis and incorporated into the several crop plants such as cotton. The toxin is coded by a gene named cry. There are a number of them like the proteins encoded by the genes cryIAc and cryIIAb control the cotton bollworms, that of cryIAb controls corn borer.