Imazalil

It is yellow to brown crystal, relative density 1.2429(23℃ ), refractive index n20D1.5643, vapor pressure 9.33×10-6Pa, m.p. 52℃ , b.p. >340℃ . Soluble in ethanol, methanol, benzene, xylene, n-heptane, hexane, petroleum ether and other organic solvents, solubility >500g/L; slightly soluble in water (0.18g/L,pH=7.6). Stable to heat, stable at room temperature and stored away from light. Inhibition of mold can be processed into sulfate or nitrate, soluble in water.

New fungicide and seed treatment agent for fruit

Imazalil is a broad-spectrum systemic fungicide used primarily in the post-harvest treatment of fruits and vegetables to prevent fungal diseases. It belongs to the imidazole class of chemicals and is widely employed to control a variety of fungal pathogens, including molds and rots that affect stored produce. Imazalil works by inhibiting the synthesis of ergosterol, an essential component of fungal cell membranes, thereby disrupting the growth and reproduction of fungi.

Key Features

1. Chemical Class: Imidazole

2. Mode of Action: Imazalil inhibits the biosynthesis of ergosterol, a vital component of fungal cell membranes, leading to cell membrane disruption and fungal death.

3. Formulations: Typically available as emulsifiable concentrates (EC), wettable powders (WP), or as a component in commercial post-harvest treatments.

4. Target Pathogens: Imazalil is effective against a wide range of fungal pathogens, including molds, rots, and mildew.

Applications

Crops

• Fruits: Oranges, lemons, apples, bananas, and other citrus fruits.

• Vegetables: Potatoes, tomatoes, and cucurbits (such as cucumbers and melons).

• Other Crops: Imazalil is also used on stored grains and other produce to prevent fungal growth during storage.

Target Diseases

• Penicillium spp.: Commonly responsible for blue mold in citrus fruits.

• Aspergillus spp.: Causes storage rot in various fruits and vegetables.

• Alternaria spp.: Responsible for Alternaria rot in tomatoes and other crops.

• Botrytis spp.: A major pathogen in grapes and strawberries.

• Fusarium spp.: Affects a wide range of crops, including bananas and potatoes.

Mode of Action

Imazalil acts by inhibiting the synthesis of ergosterol, a key component of fungal cell membranes. Without ergosterol, the cell membrane becomes destabilized, leading to the leakage of cellular contents and the eventual death of the fungal cell. This systemic action allows Imazalil to protect the fruit or vegetable from fungal infections even after application, as the chemical is absorbed into the plant tissues.

Advantages

1. Effective Post-Harvest Control: Imazalil is highly effective in preventing fungal growth on harvested fruits and vegetables, extending their shelf life and reducing spoilage.

2. Broad-Spectrum Activity: It controls a wide range of fungal pathogens, making it a versatile fungicide for various crops.

3. Systemic Action: Imazalil's systemic properties ensure that it provides long-lasting protection against fungal diseases.

4. Low Toxicity to Humans: When used according to the manufacturer's guidelines, Imazalil has low toxicity to humans and animals.

5. Prevention of Storage Rot: It is particularly useful for controlling post-harvest diseases that occur during storage and transportation of fruits and vegetables.

Usage Guidelines

1. Application Timing:

   • Pre-Harvest: Imazalil is not typically used before harvest but may be applied during post-harvest handling and storage.

   • Post-Harvest: Apply to fruits and vegetables after harvest, especially before storage, to prevent fungal infections.

   
   

2. Dosage: The recommended application rate varies depending on the crop and disease pressure. Typically, application rates range from 50 to 200 ppm, depending on the formulation and crop.

3. Spray Coverage: Ensure thorough coverage of the produce, especially in areas prone to fungal infection.

4. Reapplication Interval: Imazalil is usually applied once after harvest, but multiple treatments may be required for long-term storage.

Safety and Environmental Considerations

Handling and Storage

• Protective Measures: Wear appropriate personal protective equipment (PPE), such as gloves, goggles, and protective clothing, when handling Imazalil.

• Storage: Store in a cool, dry place away from food, feed, and water sources. Keep containers tightly sealed to avoid contamination.

Environmental Impact

• Aquatic Toxicity: Imazalil is toxic to aquatic organisms, so care should be taken to avoid runoff into water bodies.

• Soil Persistence: Imazalil has moderate persistence in the soil. Follow application guidelines to minimize environmental impact.

• Non-Target Organisms: It is generally not toxic to beneficial insects when used as directed.

Human Health Risks

• Toxicity: Imazalil is of low toxicity to humans when used according to label instructions. However, it is important to avoid inhalation or skin contact.

• First Aid:

  • Skin Contact: Wash with soap and water immediately.

  • Eye Contact: Rinse thoroughly with water for at least 15 minutes.

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

  
  

Resistance Management

To reduce the risk of resistance, it is recommended to rotate Imazalil with fungicides from different chemical classes. Overuse of any single fungicide can lead to resistance, which reduces its effectiveness over time.

Limitations

1. Resistance Risk: Imazalil, like all fungicides, can lead to resistance if used excessively or in high concentrations.

2. Rainfastness: Imazalil is rainfast after approximately 2–4 hours of application, so reapplication may be necessary after heavy rainfall.

3. Narrow Spectrum for Some Pathogens: While effective against many fungal diseases, Imazalil may not control all types of fungi, particularly those with different modes of infection.

Conclusion

Imazalil is a highly effective fungicide used primarily for post-harvest treatment of fruits and vegetables to prevent fungal diseases and extend shelf life. Its systemic action and broad-spectrum activity make it an essential tool in the post-harvest management of produce. By following recommended usage guidelines and integrating resistance management strategies, Imazalil can help reduce spoilage and ensure that crops reach consumers in optimal condition.