Azoxystrobin + Tebuconazole Fungicide: Complete Guide to Uses & Dosage
Two fungicides walked into a spray tank. One blocks fungal respiration. The other blocks ergosterol synthesis. Together, they've built a combination that fungi have never successfully developed resistance to in field conditions. That's not luck — it's chemistry.
Azoxystrobin + Tebuconazole (11% + 18.3% SC) is the most important fungicide combination in modern Indian agriculture, combining two completely different modes of action in a single application. This guide explains why it works so well and exactly how to use it.
What is Azoxystrobin + Tebuconazole Fungicide?
This is a premix fungicide combining two active ingredients from entirely different chemical classes:
- Azoxystrobin 11% — a strobilurin (SDHI-adjacent, Group 11) that inhibits mitochondrial respiration in fungi by blocking the enzyme cytochrome bc1 complex
- Tebuconazole 18.3% — a triazole (DMI, Group 3) that blocks ergosterol biosynthesis and disrupts fungal cell membrane formation
The SC (Suspension Concentrate) formulation ensures both active ingredients are uniformly distributed in every drop. Popular brands in India include Custodia (Adama), Spectrum (Dhanuka), Aleksy (DCM Shriram), and Premia.
Why Two Active Ingredients? The Resistance Logic
This is the most important thing to understand about this product, and most label instructions don't explain it clearly enough.
A fungal pathogen developing resistance to a fungicide needs to mutate the target site. Single-mode-of-action fungicides (Tilt = triazole only; Azoxystrobin = strobilurin only) have one target site to mutate. Resistance can evolve within a few seasons under heavy selection pressure.
Azoxystrobin + Tebuconazole attacks two completely different target sites simultaneously. For resistance to develop, a single fungal cell would need to mutate both sites at once. The probability of this occurring is orders of magnitude lower. In practice, this combination has maintained excellent field efficacy across years of use in India — resistance is not a practical concern when used correctly.
This is the same logic behind HIV combination therapy and antibiotic combinations. Two targets = far harder to evade.
Diseases This Combination Controls
| Disease | Crop(s) |
|---|---|
| Sheath blight | Paddy (rice) |
| Brown spot, neck blast | Paddy |
| Powdery mildew | Chilli, grapes, cucurbits, peas |
| Root rot, die-back | Chilli |
| Purple blotch, downy mildew | Onion |
| Early blight, late blight | Potato, tomato |
| Scab, brown rot | Apple, pear |
| Downy mildew | Grapes |
| Leaf rust, stripe rust | Wheat |
| Early & late leaf spot | Groundnut |
| Anthracnose | Chilli, mango |
Crops and Dosage
| Crop | Disease | Dose per acre | Interval |
|---|---|---|---|
| Paddy | Sheath blight, brown spot | 300 mL in 150–200 L water | At panicle initiation; repeat at 15 days |
| Chilli | Powdery mildew, die-back | 240–280 mL in 200 L water | At first symptom; repeat at 15 days |
| Onion | Purple blotch, downy mildew | 300 mL in 200 L water | Preventive from 45 days after transplanting |
| Potato | Early blight, late blight | 300 mL in 200 L water | Every 10–15 days during blight season |
| Grapes | Downy mildew, powdery mildew | 1 mL/8 L water | Preventive from bud burst, every 10–14 days |
| Apple | Scab, brown rot | 1 mL/8 L water | From green tip stage |
| Wheat | Rusts, leaf spot | 300 mL in 200 L water | At first rust pustule; repeat if needed |
How to Apply: Timing and Technique
- Spray at the preventive or early curative stage. The strobilurin component (Azoxystrobin) is most effective as a protectant; the triazole (Tebuconazole) adds curative power at early infection. Together they cover both scenarios, but earlier application always gives better results.
- Shake the bottle well before use. SC formulations can settle — inadequate mixing results in uneven active ingredient distribution in the spray tank.
- Use 150–200 litres of water per acre for field crops. For tree crops, spray to complete run-off for thorough canopy penetration.
- Absorbed within 2–4 hours; effective rainfastness after that window.
- Do not use more than 2 applications per season from the same combination. Rotate with a product from a different chemical family (e.g., copper oxychloride, mancozeb) between spray cycles.
Azoxystrobin + Tebuconazole vs Single-Ingredient Fungicides
- vs Tilt (Propiconazole): Tilt is a single triazole with good curative action. The Azoxystrobin + Tebuconazole combination adds the strobilurin's protective strength and has longer residual activity. For high-value crops or where disease pressure is consistently high, the combination justifies its higher cost.
- vs Nativo (Tebuconazole + Trifloxystrobin): Both are triazole + strobilurin combinations. Nativo uses Trifloxystrobin (different strobilurin) with Tebuconazole. Custodia/Spectrum uses Azoxystrobin with Tebuconazole. Rotate between them across seasons to reduce any risk of partial resistance development in the strobilurin component.
- vs Roko (Thiophanate Methyl): Roko is a benzimidazole with strong activity on blast and wilt. Azoxystrobin + Tebuconazole is stronger on rusts, sheath blight, and powdery mildew. Use in rotation, not in place of each other.
Azoxystrobin + Tebuconazole Price in India (2026)
- 250 mL: ₹480–₹620
- 500 mL: ₹900–₹1,150
- 1 litre: ₹1,700–₹2,100
Buy Azoxystrobin + Tebuconazole fungicide on Farmkart with cash on delivery across India.
Frequently Asked Questions
Q: Can I mix Azoxystrobin + Tebuconazole with insecticides?
A: Compatible with most insecticides — commonly tank-mixed with Emamectin benzoate, Chlorpyrifos, or Imidacloprid to combine disease and pest control. Do a jar test before bulk preparation.
Q: Does it work on downy mildew?
A: The Azoxystrobin component has activity on downy mildew (Oomycetes), while Tebuconazole does not. The combination provides reasonable downy mildew control, but copper-based fungicides or Metalaxyl-M combinations may be more effective for severe downy mildew outbreaks.
Q: Is this safe for organic farming?
A: No — both Azoxystrobin and Tebuconazole are synthetic fungicides, not permitted under organic certification.
Q: Pre-harvest interval?
A: 7–14 days for most crops. Always verify on the specific product label.
