UPL Dithane M45 Fungicide – Mancozeb 75% WP Broad-Spectrum Contact Fungicide for Blight, Downy Mildew, Leaf Spot & Rust

UPL Dithane M45 is a broad-spectrum, contact (non-systemic) protective fungicide trusted by Indian farmers for decades to protect field crops, fruits, and vegetables from a wide range of fungal diseases. It is based on the active ingredient Mancozeb 75% WP, which belongs to the dithiocarbamate group of compounds. Dithane M45 works by creating a protective barrier on the plant surface that stops fungal spores from germinating and penetrating plant tissue, preventing diseases before they can take hold.

This fungicide is registered for the control of many common fungal diseases including blight, leaf spot, rust, downy mildew, scab, anthracnose, and blast across crops like grapes, paddy/rice, potato, tomato, onion, groundnut, banana, wheat, maize, and chilli. Its multi-site mode of action attacks the fungus at six different enzymatic sites, which makes it very difficult for pathogens to develop resistance. In fact, no reported resistance to Dithane has been observed even after more than 45 years of commercial use, making it an excellent blend partner and a preferred choice for resistance management programs.

Beyond disease control, Dithane M45 also supplies essential micronutrients like manganese and zinc to the crop, supporting better overall plant health and growth. The very fine particle size of the formulation gives better solubility and spreading on the leaf surface, providing more uniform and reliable disease protection. It is safe for natural predators and beneficial insects, and can be applied multiple times per season without resistance risk. The recommended dose is 2 to 2.5 gm per litre of water, which works out to 600–800 gm per acre in 300 litres of water.

Key Benefits

• Broad-spectrum protection against major fungal diseases including blight, downy mildew, leaf spot, rust, anthracnose, scab, and blast in a single product.
• Multi-site mode of action attacks the fungus at six enzymatic sites, making it extremely difficult for pathogens to develop resistance even after repeated use.
• Preventive protective action forms a reliable barrier on the plant surface, stopping fungal spores from germinating and infecting plant tissue.
• Supplies essential micronutrients like manganese and zinc to the crop, supporting healthier growth and better nutrient use.
• Safe for natural predators and beneficial insects, helping maintain a balanced and environmentally friendly farming system.
• Very fine particle size gives better solubility and spreading on the leaf surface for more uniform disease protection.
• Can be applied multiple times per season without resistance risk, making it a dependable partner in resistance management programs.
• Compatible with most systemic fungicides and insecticides, ideal for tank mixing and rotation strategies.

How It Works

Dithane M45 works as a contact protective fungicide. When sprayed on the crop, it forms a thin protective layer on the surface of leaves, stems, and fruits. The active ingredient mancozeb releases an air-activated isothiocyanate compound that inactivates the SH (sulphydryl) groups in fungal enzymes. This disrupts lipid metabolism, respiration, and ATP production inside the fungal cell, leading to fungal death.

Because Dithane M45 acts upon six different enzymatic sites in the fungal cell, it inhibits spore germination and prevents the fungus from establishing infection. This multi-site action is the key reason why pathogens find it very difficult to develop resistance against this product. The product stays on the plant surface and does not move inside the plant system, so complete and uniform coverage of all plant parts is essential for best results. The very fine particle size of the formulation ensures better spreading and sticking on the leaf surface, giving more consistent and long-lasting protection.

Technical Specifications

Recommended Dosage & Application

The recommended dose is 2 gm per litre of water, which is equivalent to 30–40 gm per 15L pump and 600–800 gm per acre in 300 litres of water. Apply every 10–14 days during active disease pressure. Dithane M45 can be applied multiple times per season without resistance risk due to its multi-site mode of action. Always follow label guidance on maximum applications per season per crop.

When to Use

Dithane M45 works best as a preventive application, before disease symptoms appear. Start preventive sprays from the early vegetative stage of the crop when conditions favour fungal disease development. For Potato Late Blight, begin spraying from the canopy-closing stage. For Paddy Blast, begin from the tillering stage during humid weather.

Apply during periods of high humidity, rain, or cool weather that favours fungal infection. Spray in the early morning or late evening on a calm, dry day. Avoid peak midday heat to prevent rapid drying before the product can form its protective layer. Apply every 10–14 days during active disease pressure for continuous protection.

Step by Step Usage Instructions

1. Read the product label carefully before measuring the dose.
2. Measure 2 gm of Dithane M45 per litre of water (600–800 gm per acre in 300 litres of water).
3. Add the required amount directly into a partially filled spray tank with the agitation system running, ensuring it disperses completely into a uniform suspension.
4. Fill the tank with the remaining water and stir well to form a uniform suspension before spraying.
5. Spray as a preventive application before disease symptoms appear, especially during periods of high humidity, rain, or cool weather.
6. Apply uniformly on all plant surfaces – cover the upper and lower leaf surfaces, stems, and fruit zones completely for maximum protective coverage.
7. Spray during early morning or late evening, avoiding peak midday heat.
8. Rinse the sprayer thoroughly with clean water after every use.

Compatibility

Dithane M45 is compatible with most systemic fungicides and insecticides, making it ideal for resistance management when rotated or combined with FRAC Group 3 or 11 fungicides. It is an excellent blend partner and the preferred choice for resistance management programs. Always do a jar test before mixing with unfamiliar products to confirm compatibility.

Precautions & Safety

• Wear gloves, a mask, and goggles before handling or spraying Dithane M45.
• Do not eat, drink, or smoke while mixing or applying the product.
• Avoid direct skin and eye contact – wash immediately with plenty of clean water if contact occurs.
• Keep Dithane M45 away from children, animals, water bodies, and food sources.
• Do not spray near fish ponds or waterways – Mancozeb 75% WP is toxic to aquatic organisms.
• Wash hands thoroughly with soap and water after every spray session.
• Triple rinse empty containers, puncture, and dispose of per local waste guidelines.
• Do not enter treated fields for at least 24 hours after spraying without proper protective gear.
• Dithane M45 is restricted in Kerala – do not purchase or use in this state.

PHI / REI & Storage

• Pre-Harvest Interval (PHI): 7–21 days depending on crop (Potato/Tomato 7 days, Groundnut 14 days, Grapes 14 days, Paddy 21 days).
• Re-Entry Period (REI): Do not enter treated fields for at least 24 hours after spraying without proper protective gear.
• Shelf Life: 2 years from the date of manufacture.
• Storage Temperature: Below 35°C.
• Store in original sealed packaging in a cool, dry place away from direct sunlight and moisture.
• Keep tightly sealed after use to prevent moisture absorption and caking.
• Keep away from food, animal feed, and seeds. Store out of reach of children and farm animals.