Pretilachlor 37% EW Herbicide Uses

Pretilachlor 37% EW is a selective, pre-emergence herbicide from the chloroacetanilide group, registered for use in India under the Insecticides Act, 1968. Formulated as an emulsion (EW), it is applied to standing water shortly after transplanting rice, where it forms a treatment layer that acts on weed seeds as they germinate. This page lists its mode of action, key benefits and the recommended crop-wise dosage as per CIB-registered labels.

Which Weeds Does This Control? (Field Identification Guide)

Not sure whether the weeds coming up in your transplanted rice field are the ones this herbicide is meant to control? This guide helps you identify the grasses, sedges and broadleaf weeds it targets so you can confirm before spraying.

Mode of Action

Pretilachlor belongs to the chloroacetanilide group of herbicides (an inhibitor of very-long-chain fatty acid synthesis). It does not act on weeds that have already emerged; instead, it is absorbed by the coleoptile and young shoot tissue of grass and sedge seeds as they germinate in the treated soil-water layer, blocking cell division and elongation at these growing points. Affected weed seedlings fail to emerge properly, or die shortly after, while transplanted rice — whose root system is already established below the treated zone at the time of application — largely escapes injury at the labelled dose. Because it works on germinating weeds rather than established ones, correct timing shortly after transplanting, and maintaining a standing water layer afterward, are both critical for good control.

Features & Benefits

• Pre-emergence, soil/water-acting control that stops weeds before they compete with young transplanted rice for nutrients, light and space.
• Effective against a broad spectrum of grasses (Echinochloa spp., Digitaria sanguinalis), sedges (Cyperus spp., Fimbristylis miliacea) and several broadleaf weeds (Eclipta alba, Ludwigia parviflora, Monochoria vaginalis) common in transplanted rice.
• Water-emulsifiable (EW) formulation for straightforward tank-mixing and uniform application with standard spray equipment.
• A single, well-timed application shortly after transplanting can reduce the need for repeated early-season hand-weeding.

Recommended Usage of Pretilachlor 37% EW Herbicide

The table below gives the CIB-registered dose, water volume, timing and waiting period per acre for transplanted rice, converted from the official per-hectare rate (1 hectare ≈ 2.47 acres). Always confirm against the current product label before use.

Doses above are converted from the CIB-registered per-hectare rate (0.60–0.75 kg a.i./ha; 1.5–1.875 litres formulation/ha; 500 litres water/ha) for Pretilachlor 37% EW in transplanted rice. Always confirm the current pack label/CIB registration and consult your local agricultural extension office before use and before harvest.

How to Use

1. Apply shortly after transplanting, once the field has a thin layer of standing water, so the herbicide settles into a uniform layer at the soil-water interface where weed seeds are germinating.
2. Mix the required quantity of Pretilachlor 37% EW thoroughly into the spray tank, or apply as directed on the current label for sand/granule-mixed broadcast application if offered for this formulation.
3. Apply uniformly across the field, working backward so you do not walk through the just-treated area.
4. Avoid draining treated water out of the field for at least 3–4 days after application, so the herbicide layer is not washed away before it can act on germinating weeds.
5. Maintain a thin, standing water layer in the field for several days after application, since pretilachlor's activity depends on this water layer carrying it to germinating weed seeds.
6. Do not use on direct-seeded or newly germinating rice unless specifically permitted on the current label, since young rice without an established root system can also be affected.

Precautions & Safety

• Wear appropriate PPE — mask, gloves, goggles and full-sleeved clothing — while mixing and applying.
• Apply only at the correct crop stage (shortly after transplanting) and dose given above; early or excess application can stunt young rice seedlings.
• Maintain the recommended standing water depth after application; premature drainage or field overflow reduces weed control and can move the herbicide off-field.
• 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.
• Respect the 90-day waiting period (PHI) before harvest and follow your local agricultural extension advice for the latest guidance.
• Wash hands, face and any exposed skin thoroughly with soap and water after handling or spraying, and change out of contaminated clothing before eating, drinking or smoking.

Brand names mentioned on this page are registered trademarks of their respective owners and are referenced here for identification purposes only; FarmMate is not affiliated with or endorsed by these brands. This page is for general information only — always consult your local agricultural extension office and confirm the current product label before use.