Cry genes are present in Bacillus thuringensis. It codes for certain toxins that act as a poison to some insects, thereby, providing resistance to the plants against them and these genes are responsible for creating crystalline proteins that help to kill the pests.
There are three different types of cry genes they are cry IAB, cry IAC and cry IIAB. The IAB gene cry is responsible for managing borer pest in the corn. The genes IAC cry and IIAB cry are responsible for regulating the bollworms that damage the cotton plant.