Oxyfluorfen 23.5% EC Herbicide Uses

Oxyfluorfen 23.5% EC is a broad-spectrum herbicide from the diphenyl ether chemical group, registered for use in India under the Insecticides Act, 1968, formulated as an emulsifiable concentrate (EC). It is registered for weed control across a diverse range of crops — direct-sown rice, tea, onion and mentha — mainly as a contact/pre-emergence spray applied before or soon after 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

Oxyfluorfen belongs to the diphenyl ether family of herbicides (Group 14 / Group E) and works as a PPO (protoporphyrinogen oxidase) inhibitor. It blocks an enzyme in the chlorophyll-synthesis pathway, causing an unstable, light-reactive compound to build up inside plant cells. When this compound is exposed to sunlight, it generates highly reactive molecules that rupture cell membranes on contact, leading to rapid desiccation and burning of green tissue in susceptible weed seedlings. Because it acts mainly at the soil surface and on contact with emerging shoots, oxyfluorfen is essentially non-systemic and moves very little in the soil — it must be applied before weeds emerge, or while they are still very small, for effective control, and gives poor results once weeds are established.

Features & Benefits

• Broad-spectrum control of both grassy and broadleaf weeds across multiple crop types — direct-sown rice, tea, onion and mentha.
• Fast, visible burn-down action on susceptible weed seedlings once activated by sunlight, giving early confirmation that the spray has worked.
• Low soil mobility (non-systemic, surface-acting) reduces the risk of the herbicide moving to and injuring the roots of the main crop when used as directed.
• Suitable as a pre-emergence treatment in direct-sown rice, helping manage early-season weed competition when hand-weeding is difficult in wet fields.

Recommended Usage of Oxyfluorfen 23.5% EC 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): Rice — 150–240 g a.i./ha, 650–1000 ml formulation/ha, 500 L water/ha, PHI not specified by CIB; Tea — 150–250 g a.i./ha, 650–1000 ml formulation/ha, 500–750 L water/ha, PHI 15 days; Onion — 100–200 g a.i./ha, 425–850 ml formulation/ha, 500–750 L water/ha, PHI not specified by CIB; Mentha — 206 g a.i./ha, 904.3 ml formulation/ha, 500 L water/ha, PHI 10 days. 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 — direct-sown rice, tea, onion or mentha — and identify the weeds present using the guide above.
2. Since this is an emulsifiable concentrate (EC), it mixes directly into water — add the recommended dose to the spray tank while stirring, without needing to make a paste first.
3. Apply as a pre-emergence spray, timed relative to sowing or transplanting (not relative to weed growth stage) — spray on a well-prepared, level seedbed at or soon after sowing/transplanting, 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 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. Avoid spray contact with crop foliage where possible, since oxyfluorfen can scorch green tissue on contact — direction and timing of spray matter more than for systemic herbicides.

Precautions & Safety

• Wear appropriate PPE — mask/respirator, gloves, goggles and full-sleeved clothing — while mixing and spraying, and avoid skin contact with the concentrate.
• Oxyfluorfen belongs to herbicide Group 14 (PPO 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.
• Respect the labelled waiting period (PHI) for tea (15 days) and mentha (10 days) before harvest; for rice and onion, where CIB does not specify a PHI, follow the current product label and local extension advice.
• Because this is a contact, non-systemic herbicide, accurate timing (pre-emergence, before weeds emerge) and uniform spray coverage matter more than for systemic products — avoid delaying application once the crop is sown or transplanted.
• 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.