Question: On apraying Bacillus thuringienas on an infected cotton crop field the pesta are killed by the toxin, however the toxin although produced by the bactera does not affect it. Explain giving reason.
The correct answer is –
Bacillus thuringiensis (Bt) produces a protein toxin that is toxic to certain pests, including cotton bollworm, but is not harmful to the bacterium itself. The toxin is produced during sporulation, which is a natural part of the bacterial life cycle.
The reason why the toxin does not harm the bacterium is due to the presence of specific receptors on the surface of the pest cells that are targeted by the toxin. These receptors are absent or inaccessible on the surface of the bacterial cells. Therefore, when Bt is sprayed on the infected cotton crop, the toxin only affects the pests that have consumed the bacterial spores, while leaving the bacterium itself unharmed.
This targeted toxicity is the reason why Bt is considered an environmentally friendly and effective biological control agent for managing pest infestations in crops.
