Explanation:

Bio-insecticidal plants

Bacillus thuringiensis is the bacterium which produces an endotoxin. The bacterium contains a gene called as cry gene which produces crystal proteins. These proteins get activated in the alkaline pH of the gut of the pests. This protein causes pores in the gut which results in the bursting of the cells and death of the insects. These are considered as biopesticides because of this property. This gene from the bacterium can be used for designing plants which are resistant to pests.