Clodinafop Propargyl 9% + Metribuzin 20% WP Herbicide Uses

Clodinafop Propargyl 9% + Metribuzin 20% WP is a broad-spectrum, selective, post-emergence herbicide combination registered for use in India under the Insecticides Act, 1968, formulated as a wettable powder (WP). It combines two active ingredients with different mechanisms — clodinafop propargyl, a grass-weed-only ACCase inhibitor, and metribuzin, a broadleaf-weed-controlling PS-II inhibitor — in a single product registered for wheat, giving control over both grassy and broadleaf weeds in one spray. This page lists its mode of action, key benefits and the recommended dosage for wheat 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 wheat field match this herbicide's use case? This guide helps match weed identification to this herbicide's approved crop-wise uses.

Mode of Action

This is a dual-mechanism combination product, pairing an ACCase-inhibitor herbicide (for grass weeds) with a PS-II-inhibitor herbicide (for broadleaf weeds) in one spray:

Clodinafop propargyl belongs to the aryloxyphenoxypropionate ("FOP") family within the broader ACCase-inhibitor group of herbicides (Group 1 / Group A). It acts by inhibiting acetyl-CoA carboxylase (ACCase), an enzyme essential for fatty acid biosynthesis in actively growing plant tissue. Fatty acids are needed to build new cell membranes at a plant's growing points (meristems); by blocking ACCase, the herbicide halts membrane and lipid synthesis there, so susceptible grass weeds stop growing within a day or two of spraying — leaves and growing points typically turn reddish-purple, then yellow and brown, with the plant dying over one to three weeks. Because this type of ACCase inhibitor acts on the grass-specific (chloroplastic) form of the enzyme, it is selective to grasses and does not affect broadleaf plants. Wheat is itself a grass, but it tolerates clodinafop propargyl at the recommended dose because it rapidly metabolises (detoxifies) the herbicide into inactive compounds before it can act, whereas Phalaris minor cannot detoxify it fast enough — this differential metabolism is what gives the herbicide its crop selectivity.

Metribuzin belongs to the triazinone family within the PS-II (photosystem II) inhibitor group of herbicides (Group 5 / Group C1). It is absorbed mainly through the roots and moves upward with the plant's water flow, where it blocks electron transport at photosystem II in the chloroplasts of susceptible broadleaf weeds — a step essential to photosynthesis. This blockage prevents the weed from converting light energy into usable chemical energy, and also causes a build-up of reactive molecules that damage cell membranes, leading to rapid chlorosis (yellowing) of leaf tissue followed by necrosis (browning and death) within days of exposure. Because clodinafop propargyl controls grass weeds via ACCase inhibition and metribuzin controls broadleaf weeds via PS-II inhibition, this combination product gives season-long control across both weed categories from a single application — something the standalone grass-only clodinafop product cannot do on its own.

Features & Benefits

• Dual-action control of both grassy weeds (via clodinafop propargyl/ACCase inhibition) and broadleaf weeds (via metribuzin/PS-II inhibition) from a single spray, reducing the need for a separate broadleaf herbicide application.
• Targets Phalaris minor — the single most yield-limiting grass weed of wheat across north India — together with common broadleaf weeds like Bathua and Senji in one pass.
• Fast-acting combined mode of action; grass weeds visibly stop growing within a day or two, while broadleaf weeds show chlorosis and die back within days.
• A single, correctly timed early post-emergence spray can give season-long weed control in wheat, reducing the need for repeated hand-weeding or a second herbicide pass.

Recommended Usage of Clodinafop Propargyl 9% + Metribuzin 20% WP Herbicide

The table below gives the recommended dose, water volume and waiting period per acre for wheat, 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.

Clodinafop Propargyl 9% + Metribuzin 20% WP is registered in India only for use in wheat — no other crop use is documented in the CIB&RC list. The dose above is converted from the CIB&RC-registered per-hectare rate (a.i. 54 g clodinafop propargyl + 120 g metribuzin/ha, 600 g formulation/ha, 300 L water/ha; 1 ha ≈ 2.47 acres), which agrees closely with manufacturer label rates. Always confirm the current product label and PHI/waiting period before use.

How to Use

1. Confirm your field is sown with wheat — this herbicide's label covers wheat only, and it is not recommended for any other crop.
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. Spray uniformly over the wheat field as an early post-emergence application, once both the crop and weeds have emerged and weeds are still small — spraying later, once weeds are larger and more established, significantly reduces effectiveness for both the grass and broadleaf components.
4. Use a knapsack or power sprayer fitted with a flat-fan nozzle for uniform coverage, and spray during calm, dry weather — avoid spraying in windy conditions or when rain is expected within a few hours, as this reduces efficacy and increases drift.
5. Do not tank-mix with other herbicides of a different chemistry unless specifically recommended on the label, and avoid spray drift onto neighbouring crops.
6. Because this product has a long PHI (120 days) and carries a metribuzin component, do not re-sow the treated field with a crop other than wheat within the season without checking the label's rotational-crop restrictions.

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.
• This product combines herbicide Group 1 (ACCase inhibitor, clodinafop propargyl) and Group 5 (PS-II inhibitor, metribuzin); resistance to Group 1 herbicides in Phalaris minor is a well-documented and increasingly common problem in intensively wheat-cropped areas of Punjab and Haryana, so avoid repeated, season-after-season use of the same mode-of-action groups on the same field, and rotate with herbicides from different groups as part of an integrated weed-management program.
• Follow the recommended dose and application window strictly — both underdosing (poor weed control and faster development of resistant weed populations) and overdosing (potential crop injury, especially to a stressed or waterlogged crop) reduce field performance.
• Do not spray on a wheat crop that is under stress from waterlogging, drought, frost or nutrient deficiency, as this can increase the risk of crop injury.
• Respect the labelled waiting period (PHI) of 120 days for wheat before harvest, and follow your local agricultural extension advice for the latest guidance.
• 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.