Cyazofamid

Light yellow odorless powdery solid, m.p. 152.7°C, vapor pressure <1.33×10-5Pa, solubility in water at 20°C is 0.121 μg/mL (pH=5), partition coefficient is 3.2 (25°C).

Sulfamimidazole fungicide. Highly biologically active against oomycete fungi such as Phytophthora, Fusarium, Pseudofusarium, Pythium, and Rhizoctonia brassicae of the Rhizoctoniaceae family.

Cyazofamid is a modern fungicide belonging to the cyanoimidazole chemical class. It is highly effective in controlling diseases caused by oomycetes, such as Phytophthora and Pythium, making it a valuable tool for protecting crops like vegetables, potatoes, and ornamentals.

Key Features

1. Chemical Class: Cyanoimidazole fungicide.

2. Mode of Action: Inhibits mitochondrial respiration by targeting complex III of the electron transport chain.

3. Formulations: Available as suspension concentrates (SC) and water-dispersible granules (WDG).

4. Target Pathogens: Effective against oomycete fungi, including Phytophthora infestans and Pythium spp.

Applications

Crops

• Vegetables: Tomatoes, cucumbers, and lettuce.

• Potatoes: Protection against late blight.

• Ornamentals: Prevention of root and crown rot diseases.

Target Diseases

• Late blight (Phytophthora infestans).

• Downy mildew (Peronospora spp.).

• Root rot and damping-off (Pythium spp.).

Mode of Action

Cyazofamid disrupts mitochondrial respiration by inhibiting the Qo site of complex III in the electron transport chain. This leads to energy depletion in the pathogen, effectively stopping spore germination and mycelial growth.

Advantages

1. Highly Specific: Targets oomycetes with minimal impact on beneficial organisms.

2. Preventive Action: Provides excellent disease prevention when applied before infection.

3. Low Resistance Risk: New mode of action reduces the likelihood of resistance development.

4. Crop Safety: Safe for use on a wide range of crops without causing phytotoxicity.

Usage Guidelines

1. Application Timing: Apply preventively or at the first signs of disease.

2. Dosage: Follow label recommendations specific to the crop and disease.

3. Spray Coverage: Ensure thorough coverage of foliage and soil.

4. Reapplication Interval: Typically 7–14 days, depending on disease pressure and weather conditions.

Safety and Environmental Considerations

Handling and Storage

• Protective Measures: Use gloves, masks, and protective clothing when handling.

• Storage: Keep in a dry, cool place away from food and water sources.

Environmental Impact

• Aquatic Toxicity: Avoid runoff into water bodies to protect aquatic ecosystems.

• Soil and Water Persistence: Degrades moderately in soil; follow best practices to prevent contamination.

Human Health Risks

• Toxicity: Low toxicity to humans when used as directed; may cause mild irritation upon contact.

• First Aid:

  • Skin Contact: Wash thoroughly with soap and water.

  • Eye Contact: Flush with plenty of water for at least 15 minutes.

  • Inhalation: Move to fresh air and seek medical attention if symptoms occur.

  
  

Limitations

1. Narrow Spectrum: Primarily effective against oomycetes; not effective for other fungal classes.

2. Resistance Management: Should be used in rotation with fungicides of different modes of action.

3. Rainfastness: Moderate rainfastness; reapplication may be required after heavy rainfall.

Conclusion

Cyazofamid is a specialized fungicide for managing oomycete diseases in a wide range of crops. Its preventive action, combined with low resistance risk, makes it an essential component of integrated pest management programs. Proper application ensures robust disease control and improved crop productivity.