Question

‘‘Cotton bollworms enjoy feeding on cotton plants, but get killed when feed on Bt cotton plant.’’ Justify the statement.

Answer 1

Bt-cotton is a genetically modified (transgenic) plant that produces an insecticidal protein effective against bollworms. The bacterium Bacillus thuringiensis contains the Bt (Cry) gene, which is transferred into the cotton plant using biotechnological techniques. As a result, the plant synthesizes a crystalline Bt protein.

When insect pests feed on the plant, the toxin becomes active in their alkaline gut. It forms pores in the intestinal wall, leading to the death of the insect. This gene thus provides protection to the genetically modified cotton against pests such as budworms, bollworms, beetles and borers.