Question

In which one of the following transgenic crop Pot PI-II (Potato proteinase inhibitor –II) has been employed for insect control ?

• A. Rice, against stem borer, Scirpophaga incertulas
• B. Maize, against stem borer, Chilo partellus
• C. Tomato, against fruit borer, Helicoverpa armigera
• D. Sugarcane, against internode borer, Chilo sacchariphagus indicus

Hint:

Potato proteinase inhibitor-II (Pot PI-II) is a non-Bt plant-derived gene engineered into tomato crops to inhibit protein digestion in the gut of the fruit borer, Helicoverpa armigera.

Answer 1

The Correct Option is C

Step 1: Understanding the Concept:
Transgenic crops can be engineered with plant-derived genes, such as protease inhibitors, to protect against insect pests.
These inhibitors interfere with the digestive enzymes of herbivorous insects, reducing their growth and survival.

Step 2: Detailed Explanation:
The Potato proteinase inhibitor-II (Pot PI-II) is a serine protease inhibitor that targets digestive trypsin and chymosin-like enzymes in the insect gut.
When an insect feeds on transgenic tissue expressing Pot PI-II, the inhibitor binds to these digestive enzymes, preventing protein digestion and causing amino acid deficiency, stunted growth, and mortality.
This transgenic technology has been successfully introduced into tomato plants to provide resistance against the tomato fruit borer, Helicoverpa armigera.
The fruit borer is a highly destructive pest of tomato crops, and expressing Pot PI-II in the leaves and fruits significantly reduces larval feeding and damage.
While Bacillus thuringiensis (Bt) genes are also used for pest control, the Pot PI-II gene is a key non-Bt alternative used specifically in tomato biotechnology.

Step 3: Final Answer
The correct option is (C).