Metiram is a broad-spectrum, protectant fungicide belonging to the dithiocarbamate chemical group.
It is commonly formulated as WP (Wettable Powder) or WG/WDG (Water-Dispersible Granules).
Metiram is a contact fungicide that acts on the surface of plant tissues, preventing fungal infections by inhibiting multiple enzyme systems within fungal cells.
Because of its multi-site mode of action, Metiram has a low risk of resistance development.
✅ 2. Chemical & Physical Properties
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Common Name: Metiram
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Chemical Group: Dithiocarbamate fungicide
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CAS Number: 9006-42-2
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Molecular Formula: C₈H₁₈N₄S₈Zn
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Formulation Types:
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70% WP
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75% WG
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80% WDG (depending on manufacturer)
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Appearance: Grayish-yellow powder or granules
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Solubility: Insoluble in water; dispersible with agitation
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Mode of Action:
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Multi-site inhibitor; blocks fungal enzymatic systems
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Prevents spore germination
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Strong protectant activity
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Physical Characteristics:
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Good rainfastness once dry
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Adheres well to plant surfaces
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Stable in proper storage
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✅ 3. Key Features & Benefits
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Broad-spectrum protectant fungicide
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Low resistance risk (multi-site activity)
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Excellent preventive action
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Effective against many foliar fungal diseases
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Compatible with tank mixes (depending on pH)
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Low phytotoxicity on labeled crops
✅ 4. Applications & Uses
Metiram is widely used in vegetables, fruits, cereals, nuts, and ornamentals.
🌿 A. Fruit Crops
Grapes
Controls:
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Downy mildew (Plasmopara viticola)
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Black rot
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Phomopsis cane & leaf spot
Apple / Pear
Controls:
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Scab
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Alternaria leaf blotch
Citrus
Controls:
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Citrus scab
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Melanose
🍅 B. Vegetables
Tomato, Potato
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Early blight
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Late blight (as part of a program)
Cucumber, Melon, Pumpkin
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Downy mildew
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Anthracnose
Onion & Garlic
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Purple blotch
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Downy mildew (preventive)
🌾 C. Cereals & Row Crops
Wheat, Barley
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Leaf spot complex
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Rust diseases (supportive use)
Soybean
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Anthracnose
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Downy mildew
🌰 D. Nut Crops
Walnut, Hazelnut
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Leaf spot diseases
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Brown rot
🌺 E. Ornamentals
Common uses:
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Leaf spots
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Blights
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Flower diseases
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Downy mildew
🧪 5. Mode of Application
Metiram is typically applied as:
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Foliar spray with high coverage
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Ground sprayers
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Airblast sprayers in orchards
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Used in regular preventive spray programs
Frequency of spraying usually depends on:
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Crop growth stage
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Disease pressure
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Weather conditions
🛡️ 6. Advantages in Crop Protection
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Excellent surface protection
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Multi-site mechanism → very low resistance risk
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Valuable rotation partner in IPM programs
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Effective during wet and humid conditions
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Uniform coverage and persistence
