Atrazine 50% WP Herbicide Uses

Atrazine 50% WP is a classic triazine herbicide registered for use in India under the Insecticides Act, 1968, formulated as a wettable powder (WP). It is one of the oldest and most widely used herbicides in maize and sugarcane cultivation in India, registered for pre-emergence weed control — applied soon after sowing or planting, before weeds emerge. This page lists its mode of action, key benefits and the recommended dosage per crop as per the official Central Insecticides Board & Registration Committee (CIB&RC) list of approved herbicide uses (Government of India), cross-checked against manufacturer labels.

Which Weeds Does This Control? (Field Identification Guide)

Not sure whether the weeds in your field match this herbicide's use case? This guide helps match weed identification to this herbicide's approved crop-wise uses.

Mode of Action

Atrazine belongs to the triazine family of herbicides (Group 5 / Group C1) and works as a PS-II (photosystem II) inhibitor — the same broad mechanism shared by other triazine and related herbicides. It is absorbed mainly through the roots of germinating and young weed seedlings and moves upward with the plant's water flow into the leaves, where it blocks electron transport at photosystem II in the chloroplasts — a step essential to photosynthesis. This blockage prevents the weed seedling from converting light energy into usable chemical energy, and also causes a build-up of reactive molecules that damage cell membranes, leading to chlorosis (yellowing) of leaf tissue followed by necrosis (browning) and death of the seedling within days to a couple of weeks. Atrazine is primarily soil-acting and is applied as a pre-emergence treatment — soon after sowing (in maize) or planting (in sugarcane) and before weeds emerge — since it works mainly on germinating seedlings absorbing it through their roots, rather than on established weeds.

Features & Benefits

• One of the oldest, most widely used and well-understood pre-emergence herbicides in maize and sugarcane cultivation across India.
• Broad-spectrum control of both grassy and broadleaf weeds, including major problem weeds like Trianthema, Digera, Echinochloa and Amaranthus in maize, and Portulaca, Digitaria and Tribulus in sugarcane.
• Applied early — soon after sowing/planting — so it gives season-early weed control before weeds compete with the young crop for nutrients, light and water.
• Economical, well-established use pattern with a long track record in Indian field conditions.

Recommended Usage of Atrazine 50% WP Herbicide

The table below gives the recommended dose, water volume and waiting period per acre for each crop, converted from the CIB&RC-registered per-hectare rate — see the note below the table for conversion details. Always spray in the recommended water volume for uniform coverage, and confirm against the current product label before use.

Figures above are converted from the CIB&RC-registered per-hectare rates (1 ha ≈ 2.47 acres): Maize — 0.5–1.0 kg a.i./ha, 1–2 kg formulation/ha, 500–700 L water/ha, PHI not specified by CIB; Sugarcane — 0.50–2.00 kg a.i./ha, 1.00–4.00 kg formulation/ha, 500–700 L water/ha, PHI not specified by CIB. Where CIB does not specify a PHI, no figure has been assumed — always confirm the current product label before use.

How to Use

1. Confirm your crop matches this herbicide's approved use — maize or sugarcane — and identify the weeds present using the guide above.
2. Since this is a wettable powder, first mix the recommended dose into a small quantity of water to make a smooth, lump-free paste, then add this to the full spray tank volume while stirring continuously so it disperses evenly.
3. Apply as a pre-emergence spray, timed relative to sowing (maize) or planting (sugarcane) — not relative to weed growth stage — spraying onto a well-prepared, level field soon after sowing/planting and before weeds emerge, for best results.
4. Use a knapsack or power sprayer fitted with a flat-fan nozzle for even ground coverage, and avoid overlapping spray passes which can cause crop injury from excess dose.
5. Pre-emergence herbicides work best on moist soil — spray onto a moist, well-prepared seedbed, and a light irrigation shortly after spraying (where the crop allows) helps activate the herbicide and improve weed control.
6. Spray during calm weather, avoiding windy conditions and rainfall expected within a few hours, to reduce drift and wash-off.
7. Do not delay application once the crop is sown or planted — atrazine works mainly on germinating weed seedlings, so timing relative to sowing/planting matters more than for a post-emergence product.

Precautions & Safety

• Wear appropriate PPE — mask/respirator, gloves, goggles and full-sleeved clothing — while mixing and spraying, and avoid inhaling the wettable powder dust while opening the pack.
• Atrazine belongs to herbicide Group 5 (PS-II inhibitors); avoid repeated, season-after-season use of the same mode-of-action group on the same field, and rotate with herbicides from a different group as part of an integrated weed-management program to slow resistance development.
• Atrazine has well-documented soil persistence and can carry over in soil beyond the treated crop's season — take particular care about which crop is planted next in rotation, and check the label for rotational-crop restrictions before sowing a sensitive follow-up crop in the treated field.
• Where CIB does not specify a PHI for maize or sugarcane, follow the current product label and local agricultural extension advice on the appropriate waiting period before any produce is used.
• Because this is primarily a soil-acting, pre-emergence herbicide, accurate timing (soon after sowing/planting, before weeds emerge) and uniform spray coverage matter more than for post-emergence products.
• Store in the original, tightly closed container in a cool, dry place away from direct sunlight, food and feed, and out of reach of children and livestock.
• 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.