Which of the following is NOT a type of adjuvant?

In herbicide application, adjuvants are substances added to a pesticide formulation to enhance its effectiveness. They improve various properties of the herbicide, such as its spreading, sticking, or dispersing characteristics.

Wetting agents, for instance, help reduce the surface tension of a liquid, allowing it to spread more evenly over plant surfaces. Spreaders improve the coverage and adherence of herbicides on the target plants, ensuring that they remain on the plant surfaces longer for maximum efficacy. Drift control additives are designed to minimize the movement of herbicide spray droplets off-target, thereby enhancing application accuracy and reducing environmental impact.

Antifungal agents, on the other hand, are not classified as adjuvants. They are a specific type of pesticide used to prevent or manage fungal diseases in plants. While they serve an important purpose within pest management, they do not function in the capacity of modifying herbicide behavior or increasing its effectiveness during application like the other options do. Therefore, identifying antifungal agents as not being a type of adjuvant is accurate in the context of herbicide application.