Daconil

Daconil is a brand of fungicides whose active ingredient is chlorothalonil. The Daconil formulations are produced and sold by various agricultural chemical companies for use in horticulture, agriculture, and turf management. Daconil products are used to protect foliage, fruit, and ornamental plants from a broad range of fungal diseases, including many leaf spots, blights, mildews, and rots.

Chlorothalonil acts as a contact fungicide with broad-spectrum activity. It forms a protective film on leaf surfaces and inhibits fungal development at multiple sites, which helps prevent infection rather than curing existing infections. Because it is not systemic, effectiveness depends on timely application, good coverage, and rainfastness. Rain, sunlight, and plant growth can reduce residual protection, so reapplication is often required under ongoing disease pressure. Daconil is commonly applied on vegetables, fruits, grapes, ornamentals, and turfgrass, and is used in both greenhouse and field settings.

Formulations of Daconil include liquid concentrates suitable for dilution in water, water-dispersible granules, and ready-to-use sprays such as WeatherStik variants. Labels provide crop-specific guidance, recommended rates, intervals, and safety precautions, as well as pre-harvest intervals and re-entry times.

Safety and environmental notes emphasize following the product label. Daconil formulations can be toxic to aquatic organisms; users should avoid spray drift into waterways and worn protective equipment during mixing and application. It should not be used in ways that violate local regulations. As a preventive fungicide with a multi-site mode of action, resistance management typically involves rotating with fungicides that have different modes of action.