Diquat (Reward) is classified as which type of herbicide?

• A. Non-selective systemic herbicide
• B. Selective contact herbicide
• C. Contact cell membrane disruptor herbicide
• D. Persistent soil herbicide

Answer: (C)

Diquat, marketed as Reward, is classified as a contact cell membrane disruptor herbicide, which means it works by damaging the cell membranes of plant tissues, leading to rapid desiccation of the target weeds. When applied, diquat primarily affects the tissue it contacts, making it effective almost immediately for controlling annual weeds and some perennial species. This mode of action contrasts with other herbicide classifications, such as systemic herbicides, which are absorbed and translocated throughout the plant, affecting areas not directly contacted by the application. The focus on cell membrane disruption highlights the quick action of diquat, making it suitable for specific applications where fast results are desired.