Thiophanate Methyl 70% WP: Complete Guide — Active Ingredient in Roko & Prism
You've probably used Thiophanate Methyl without knowing it. If you've sprayed Roko on your paddy crop, or Prism on your vegetables, or any of dozens of other systemic fungicides on Indian farms — that's Thiophanate Methyl. It's the active ingredient behind one of the most widely used fungicide formulations in India, and understanding what it does helps you use every product containing it more effectively.
This guide covers Thiophanate Methyl 70% WP as an active ingredient — what it is, how it works, which products contain it, and the complete dosage and application guide for Indian farmers.
What is Thiophanate Methyl 70% WP?
Thiophanate Methyl is a systemic benzimidazole fungicide — the active ingredient in a wide range of fungicide products sold under different brand names across India. The "70% WP" refers to 70% active ingredient in a Wettable Powder formulation.
Major Indian brands containing Thiophanate Methyl 70% WP:
- Roko (Biostadt India Limited) — the most widely recognised brand
- Prism (Insecticides India Limited)
- KIRIN (Parijat Industries)
- Riico (various)
- Numerous generic formulations from regional manufacturers
All these products contain the same active ingredient at the same concentration (70% WP). The choice between them comes down to price, availability, and brand trust.
How Does Thiophanate Methyl Work?
Thiophanate Methyl is a pro-fungicide — it is not directly active but converts inside the plant to its active form, Carbendazim (MBC — methyl benzimidazole carbamate).
MBC inhibits the polymerisation of tubulin — the protein that forms the spindle fibres needed for fungal cell division. Without functional spindle fibres, fungal cells cannot divide. The fungus is first arrested (fungistatic), then killed (fungicidal) as existing cells eventually die without replacement.
This mechanism gives Thiophanate Methyl three distinct advantages:
- Systemic activity — absorbed through roots and leaves, transported throughout the plant via xylem
- Curative as well as preventive — can arrest established early infections, not just prevent new ones
- Phytotonic effect — the slow conversion process and improved plant metabolism leads to mildly enhanced plant vigour at recommended doses
Diseases Thiophanate Methyl 70% WP Controls
| Disease | Crop(s) |
|---|---|
| Blast (leaf & neck blast) | Paddy |
| Sheath blight | Paddy |
| Powdery mildew | Wheat, tomato, grapes, cucurbits |
| Scab (Venturia) | Apple, pear |
| Anthracnose | Chilli, mango, papaya |
| Botrytis (grey mould) | Tomato, grapes, strawberry |
| Sclerotinia stem rot | Soybean, sunflower, mustard |
| Fusarium wilt / damping off | Tomato, brinjal, chilli (nurseries) |
| Cercospora leaf spot | Groundnut, tomato |
| Loose smut / seed-borne fungi | Wheat, barley (seed treatment) |
| Gummy stem blight | Cucurbits |
Dosage Chart by Application Method
| Application | Crop | Dose |
|---|---|---|
| Foliar spray | Paddy, vegetables, fruits | 1 g/L water (500–600 g/acre in 200 L) |
| Seed treatment | Wheat, paddy, vegetables | 2–3 g per kg of seed |
| Soil drench | Nursery seedlings, flower beds | 2–4 g/L water |
| Tuber/rhizome dip | Potato, ginger, turmeric | 1–2 g/L water; soak for 30 minutes before planting |
| Post-harvest dip | Fruits (mango, citrus) | 0.5–1 g/L water |
The versatility across application methods is one of Thiophanate Methyl's greatest strengths. Very few fungicide actives work equally well as foliar sprays, seed treatments, soil drenches, and post-harvest dips.
Application Tips
- Spray at first symptom or preventively in high-risk seasons. As a systemic, it works best at low to moderate disease pressure. Once >30% of the canopy is infected, curative efficacy drops significantly.
- Repeat at 10–14 day intervals if disease pressure is sustained. Maximum 2–3 sprays per season before rotating chemical class.
- For nursery damping-off: soil drench at 2–4 g/L at transplanting or seeding provides systemic protection to young roots — one of the most cost-effective disease management steps in vegetable production.
- For seed treatment: dry treat the seed 24–48 hours before sowing. The systemic activity protects against seed-borne fungi during germination and early establishment.
- Resistance management: Benzimidazole resistance is documented in some pathogen populations after decades of continuous use (notably in Botrytis cinerea and certain Fusarium strains). Rotate with fungicides from different chemical groups — triazoles (Tilt, Nativo), strobilurins, or copper-based products — every alternate spray.
Thiophanate Methyl 70% WP Price in India (2026)
Prices vary by brand. Generics are significantly cheaper than Roko (Biostadt's branded version):
- Generic 250 g: ₹90–₹150
- Generic 500 g: ₹160–₹270
- Generic 1 kg: ₹300–₹450
- Roko (Biostadt) 250 g: ₹280–₹350
- Roko 1 kg: ₹1,100–₹1,367
The generic versions contain the same active ingredient at the same concentration. The price difference reflects brand premium. For routine disease prevention on lower-value crops, generics are cost-effective. For high-value crops or where brand QC matters, Roko or Prism are trusted choices.
Buy Thiophanate Methyl 70% WP fungicide on Farmkart — multiple brands available with cash on delivery.
Frequently Asked Questions
Q: Is Thiophanate Methyl the same as Carbendazim?
A: They are related but different. Thiophanate Methyl converts to Carbendazim inside the plant. Carbendazim (50% WP) is sold directly as a separate product. Both have similar efficacy, but Thiophanate Methyl is considered to have slightly better plant safety at recommended doses on certain crops.
Q: Can I use Thiophanate Methyl on flowering crops?
A: Yes — it is not toxic to bees or pollinators and can be applied on flowering crops. Spray in the evening as a standard precaution.
Q: Pre-harvest interval?
A: 7–10 days for most vegetable and fruit crops. Check the specific product label.
Q: Is Thiophanate Methyl effective against downy mildew?
A: No — downy mildew is caused by Oomycetes, not true fungi, and benzimidazoles are not effective against Oomycetes. Use Metalaxyl, copper-based products, or dedicated downy mildew fungicides.
