Bt toxins are insect group specific proteins. Gene named cryIAc and cryIIAb control:
Answer & explanation
Correct answer: option 1
The correct answer is Option (1) → Cotton bollworms
Option (1) Cotton bollworms — Correct. Bt toxin is coded by the cry genes, each specific to a group of insects. The proteins of cryIAc and cryIIAb control cotton bollworms; that of cryIAb controls the corn borer.
NCERT Extract:
Biotechnological Applications in Agriculture – “… Specific Bt toxin genes were isolated from Bacillus thuringiensis and incorporated into the several crop plants such as cotton (Figure 10.1). The choice of genes depends upon the crop and the targeted pest, as most Bt toxins are insect-group specific. The toxin is coded by a gene cryIAc named cry. There are a number of them, for example, the proteins encoded by the genes cryIAc and cryIIAb control the cotton bollworms, that of cryIAb controls corn borer.”