An insecticide used for seed treatment against sucking insect pests is:

Correct option is C

Imidacloprid is a systemic insecticide belonging to the neonicotinoid group. It is widely used for seed treatment, especially against sucking insect pests such as:
· Aphids
· Whiteflies
· Jassids (leafhoppers)
· Thrips
�� Why Imidacloprid for Seed Treatment?
· Systemic Action: After seed germination, the chemical is absorbed by the roots and distributed throughout the plant, making it effective from the inside.
· Long-lasting protection: Offers protection during the early growth stages when plants are most vulnerable.
· Target-specific: Highly effective against piercing and sucking insects.
· Low application dose: Only a small quantity is needed for effective control.
Used extensively in crops like cotton, rice, maize, vegetables, and pulses for prophylactic pest control.
Explanation for Each Option
(a) Quinalphos ❌
· An organophosphate insecticide used mainly as a foliar spray, not preferred for seed treatment.
(b) Decamethrin ❌
· A pyrethroid insecticide, also used as a foliar spray. It is not systemic and hence ineffective for seed treatment.
(c) Imidacloprid ✅
· Correct answer.
· A systemic neonicotinoid used effectively for seed treatment to control sucking pests.
(d) Phorate ❌
· A granular organophosphate, used mostly in soil application, not preferred for seed treatment due to high toxicity and handling risk.