A Bt Corn is Field corn that has received a gene transferred from a naturally-occurring soil bacterium called Bacillus thuringiensis. The gene causes the corn plant to produce one of several insecticidal compounds commonly called Bt toxins. The toxins affect the midgut of particular groups of insects such as European corn borer that can be harmful to corn.

---

Other /More definition:
A Bt Corn is a field corn that has received a gene transferred from a naturally-occurring soil bacterium called Bacillus thuringiensis. The gene causes the corn plant to produce one of several insecticidal compounds commonly called Bt toxins. The toxins affect the midgut of particular groups of insects such as European corn borer that can be harmful to corn.