Question

Which among the followings is used as modifier for herbicides?

• A. Butylate
• B. Dazomet
• C. Dietholate
• D. Molinate

Hint:

Herbicide extenders like dietholate prevent "accelerated biodegradation" of carbamothioate herbicides in soils that have had prior repeated exposures to the same chemical.

Answer 1

The Correct Option is C

Step 1: Understanding the Concept:
Herbicide modifiers (also known as safeners, extenders, or synergists) are chemicals added to herbicide formulations to modify their activity, enhance crop safety, or alter persistence.

Step 3: Detailed Explanation:
- Butylate (A) and Molinate (D): These are thiocarbamate herbicides, not modifiers.
- Dazomet (B): This is a chemical soil fumigant used to control weeds, nematodes, and soil pathogens.
- Dietholate (C): This is used as a herbicide extender/modifier. When applied to soil, it inhibits the soil microbes that rapidly degrade thiocarbamate herbicides (such as EPTC or butylate). By slowing down biodegradation, dietholate extends the persistence and efficacy of the herbicide in the soil.

Step 4: Final Answer:
The chemical used as a modifier/extender is Dietholate, which corresponds to option (C).