Which one of the following pairs of genes can control the cotton bollworms?
Answer & explanation
Correct answer: option 3
The correct answer is Option (3) → cryIAc and cryIIAb
Bt toxin is a protein made by the bacterium Bacillus thuringiensis. It kills certain insects. The gene for this toxin is called cry. There are many cry genes, and each Bt toxin acts on a particular group of insects. So the gene put into a crop is chosen according to the crop and the pest.
(1) cryIAb and cryIIAb — Incorrect. The protein of cryIAb controls the corn borer, not the cotton bollworm.
(2) cryIAb and cryIAc — Incorrect. Again, cryIAb is the corn borer gene.
(3) cryIAc and cryIIAb — Correct. The proteins coded by cryIAc and cryIIAb control the cotton bollworms. These genes are used in Bt cotton.
(4) cryIIAc and cryIIAb — Incorrect. The first gene of the correct pair is cryIAc, not cryIIAc.
NCERT Extract:
Biotechnological Applications in Agriculture – …
