Cry proteins are a group of toxic protein which are highly poisonous to deficient types of insects. It is produced by a soil bacterium Bacillus thuringiensis. The genes controlling their formation are called crygenes
eg:- Cry I Ab, Cry I Ac, Cry II Ab, The bacterium produces protein in the crystal form of protoxin. Two cry genes have been incorporated in cotton (Bt cotton) while one has been introduced in corn (Bt corn) As a result Bt Cotton was disease resistance to boll worm and Bt corn was resistance to corn borer.
