Question

How would you produce pest resistant plants?

Hint:

Recall Bt cotton and the cry-gene toxin mechanism as the standard example.

Answer 1

Step 1: Genetic Engineering Approach:
Pest-resistant plants are produced by genetically engineering crop plants to carry and express a gene from the soil bacterium Bacillus thuringiensis (Bt) that codes for a protein toxic to specific insect pests, such as the cry genes (e.g., cryIAc, cryIAb).

Step 2: How the Toxin Works:
The cry gene is introduced into the plant's genome so the plant itself produces the Bt toxin protein in its tissues; when a susceptible insect larva feeds on the plant, the toxin binds to its midgut cells, causing them to swell and lyse, killing the insect, while the toxin is harmless to non-target organisms including humans.