Question

Cotton is protected from boll worm by using bacterium ______________.

• A. Escherichia coli
• B. Bacillus thuringiensis
• C. Rhizobium leguminosarum
• D. Salmonella typhimurium

Hint:

Bt cotton is a transgenic crop expressing Cry toxin genes.

Answer 1

The Correct Option is B

Step 1: Understanding boll worm control.
Boll worm is a major insect pest of cotton that damages bolls and reduces yield.
Step 2: Role of Bacillus thuringiensis (Bt).
Bacillus thuringiensis produces crystal (Cry) proteins which are toxic to insect larvae when ingested.
Step 3: Mechanism of action.
Cry proteins destroy the gut lining of boll worm larvae, leading to their death without harming humans or plants.
Step 4: Conclusion.
Therefore, cotton is protected from boll worm by using Bacillus thuringiensis.