Metalaxyl 35% WS Fungicide Uses

Metalaxyl 35% WS is a systemic, benzenoid-class fungicide registered for use in India under the Insecticides Act, 1968 and sold under various trade names including Metsac and Moxyl. Formulated specifically as a water-dispersible seed treatment (WS), it is used exclusively as a seed dressing — not as a foliar spray — across maize, bajra (pearl millet), sorghum, sunflower and mustard to protect the germinating seed and seedling from downy mildew and related soil-borne diseases. Metalaxyl remains legally registered and sold in India; always confirm the current pack label before use. This page lists its mode of action, key benefits and the recommended crop-wise seed treatment dosage as per manufacturer labels.

Mode of Action

Metalaxyl belongs to the phenylamide (acylalanine) class of fungicides and acts systemically against Oomycete pathogens — a group of fungus-like organisms that includes Pythium, Phytophthora and the downy mildew pathogens (Peronosclerospora and Sclerospora species) and Albugo species (which causes white rust). It works by inhibiting RNA polymerase I inside the pathogen, blocking the synthesis of ribosomal RNA that the organism needs to grow and reproduce. Applied as a seed treatment, metalaxyl is taken up by the germinating seed and moves systemically into the emerging seedling, giving protection against seed-borne and soil-borne downy mildew and damping-off infection from the moment of germination, without needing a separate foliar spray at this early stage.

Features & Benefits

• Targeted, systemic protection against downy mildew and Pythium/Phytophthora-driven damping-off, right from seed germination.
• Seed treatment application means protection begins before the pathogen can establish, reducing early-season crop loss and the need for follow-up fungicide sprays.
• Low dose rates (a few hundred grams of product per 100 kg of seed) make it a cost-effective, low-volume input applied once at sowing.
• Usable across a wide range of field crops — maize, bajra, sorghum, sunflower and mustard — each with its own labelled target disease.

Recommended Seed Treatment Usage of Metalaxyl 35% WS

The table below gives the commonly recommended seed treatment dose for each crop and target disease, as listed on manufacturer labels for this active ingredient. All uses listed are seed dressing (seed treatment), not foliar spray. Always confirm against the current product label before use.

Doses above are the commonly listed formulation-label rates for Metalaxyl 35% WS as a seed treatment, expressed as grams of product per 100 kg of seed. Waiting periods of roughly 3–4 months (varying by crop) are listed on manufacturer labels for the growing season as a whole; always confirm the current pack label/CIB registration and consult your local agricultural extension office for the latest guidance.

How to Use

1. Identify your crop and target disease from the table above, and confirm the correct dose per 100 kg of seed.
2. Measure the required quantity of Metalaxyl 35% WS for the total seed lot to be treated, and mix it with the specified quantity of water to form a uniform slurry.
3. Spread the seed in a shaded area and apply the slurry evenly, mixing thoroughly (by hand with gloves, or in a mechanical seed treatment drum) so every seed gets a uniform coating.
4. Dry treated seed in shade before sowing or storage — do not dry in direct sunlight, and do not sow wet-treated seed immediately if the label specifies a drying period.
5. Sow treated seed within the time frame recommended on the label, and do not use treated seed for food, feed or oil extraction — clearly mark and store it separately from untreated seed.

Precautions & Safety

• Wear appropriate PPE — mask/respirator, gloves, goggles and full-sleeved clothing — while handling and mixing the seed treatment product, and while treating and handling coated seed.
• Ensure treated seed is fully covered by soil at sowing so that no treated seed remains exposed on the surface where birds or other wildlife could access it.
• Never use metalaxyl-treated seed for human or animal consumption, or for oil extraction — treated seed is for sowing only.
• Store in the original, tightly closed container in a cool, dry place away from direct sunlight, food, feed and out of reach of children and livestock.
• Metalaxyl is a single-site fungicide (phenylamide/acylalanine class); resistant strains of some Oomycete pathogens are known, so avoid relying on it as the sole disease-management tool across seasons and follow any label guidance on resistance management.
• Wash hands, face and any exposed skin thoroughly with soap and water after handling, and change out of contaminated clothing before eating, drinking or smoking.