Copper Oxychloride 50% WP Fungicide Uses

Copper Oxychloride 50% WP is a protectant, multi-site contact fungicide from the inorganic copper group, registered for use in India under the Insecticides Act, 1968, formulated as a wettable powder (WP). It carries a broad label across fruit, vegetable, plantation and field crops for the control of a wide range of fungal diseases — including downy mildew, anthracnose and late blight — and, unusually for a fungicide, also has meaningful activity against bacterial plant diseases such as citrus canker and bacterial leaf spot. This page lists its mode of action, key benefits and the crop-wise recommended dosage as documented in the Central Insecticides Board & Registration Committee's (CIB&RC) official list of approved fungicide uses (Government of India), the ranked source of record, cross-checked against the TNAU Agritech portal and independent manufacturer labels.

Which Problem Is This For? (Symptom Guide)

Not sure whether what you're seeing in the field matches this fungicide's use case? This guide helps match symptoms to this fungicide's approved crop-wise uses.

Mode of Action

Copper oxychloride is a protectant, multi-site, inorganic contact fungicide with no systemic movement within the plant — it must be applied ahead of infection to be effective, coating the plant surface. In the presence of moisture (dew, rain or high humidity), the copper compound slowly releases free cupric (Cu²⁺) ions on the leaf or fruit surface. These copper ions are directly toxic on contact to fungal spores and bacterial cells: they denature proteins and enzymes and disrupt several different essential cellular processes at once inside the invading spore or bacterial cell, preventing spore germination and bacterial multiplication before infection can become established in plant tissue. Because copper acts on many different biochemical targets rather than one single site, resistance development is very rare — copper-based fungicides have remained effective against many pathogens even after well over a century of continuous agricultural use, dating back to the invention of Bordeaux mixture in the 19th century. Copper is somewhat unusual among fungicides in also having meaningful activity against bacterial plant pathogens, which is why it remains one of the few chemical options for diseases such as citrus canker and bacterial leaf spot, alongside its primary fungicidal role.

Features & Benefits

• Dual fungicidal-and-bactericidal action from a single product — valuable against both fungal diseases (downy mildew, anthracnose, late blight) and bacterial diseases (citrus canker, bacterial leaf spot) on the same or neighbouring crops.
• Multi-site protectant action gives an extremely low risk of the pathogen developing resistance, even after very long-term historical use across agriculture.
• Broad crop label spanning fruit, vegetable, plantation and field crops, making it a versatile general-purpose protectant fungicide for many farm situations.
• A well-established, relatively low-cost input with a long, well-understood usage history in Indian agriculture.

Recommended Usage of Copper Oxychloride 50% WP Fungicide

The table below gives the recommended dose for each crop and disease, based on the Government of India's CIB&RC official fungicide dosage list for this exact formulation — see the note below the table for the per-hectare-to-per-acre conversion. Always spray in sufficient water volume for uniform coverage, and confirm against the current product label before use.

The CIB&RC official fungicide dosage list for this exact Copper Oxychloride 50% WP formulation gives grapes (downy mildew) a dose of 2.5 kg formulation per hectare in 750–1000 litres of water — converting at 1 ha ≈ 2.47 acres, this works out to almost exactly 1 kg per acre in 300–400 litres of water, the same general-purpose rate shown above for potato, citrus, chilli, tomato, banana and coconut (and matching a major-brand Rallis/Tata commercial label for this formulation). A mango (anthracnose) entry for copper oxychloride does exist in the CIB&RC list, but only under a different formulation — Copper Oxychloride 50% WG (a granule, not this wettable-powder product) — so it has been removed from this page rather than carried over from a formulation this product isn't; a TNAU Agritech figure for mango on this WP formulation is not supported by CIB&RC and is not shown here. Always follow the dose printed on your specific product's current label, and consult your local agricultural extension office if in doubt.

How to Use

1. Identify your crop and target disease from the table above, and confirm the correct dose/concentration on your product's current label.
2. Mix the required quantity of Copper Oxychloride 50% WP into a small amount of water first to make a smooth paste, then add this to the full spray tank volume while stirring continuously, so the wettable powder disperses evenly and does not settle or clog the nozzle.
3. Since this is a protectant, contact fungicide with no systemic movement, spray before infection is expected (ahead of forecast humid/wet weather) or at the very first sign of disease, and ensure thorough, even coverage of all plant surfaces, including the undersides of leaves.
4. Use a knapsack or power sprayer fitted with a suitable nozzle, and spray during calm, dry weather — avoid spraying in windy conditions or when rain is expected within a few hours, as this washes off the protective copper deposit and reduces efficacy.
5. Repeat sprays at 10–15 day intervals during periods of high disease pressure or favourable weather, or as advised by local agricultural extension, and reapply after heavy rain since copper deposits can be washed off the plant surface.

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.
• Repeated, heavy, long-term use of copper-based fungicides can lead to copper accumulation in soil over many years, which in some situations may affect soil microbial activity or earthworm populations; avoid excessive, unnecessary applications and follow the recommended dose and spray interval.
• Avoid tank-mixing with strongly alkaline materials or with certain other pesticides without checking compatibility first, and avoid spraying copper on a crop under heat or moisture stress, as this can occasionally cause leaf russeting or scorch on sensitive varieties.
• Copper Oxychloride can be phytotoxic to certain sensitive crops or varieties at high concentrations or under cool, slow-drying conditions; if using on a crop for the first time, consider a small test-patch spray before treating the whole field.
• 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.