Imazalil is a fungicide widely used in agriculture, particularly in the growing of citrus and banana fruits. Imazalil is also used in veterinary as a topical antimycotic.
What Is Imazalil?
Imazalil is a common name (BSI, E-ISO, (m) F-ISO, ANSI); In South Africa, it is usually called chloramizol; moreover the international nonproprietary name is enilconazole which has been banned.
Table 1 Physical & Chemicals Property of Imazalil
| Common Name | Imazalil |
| IUPAC name | (RS)-1-(β-allyloxy-2,4-dichlorophenethyl)imidazole. |
| CAS No. | 35554-44-0 |
| Mol. wt. | 297.2 |
| M.f. | C14H14Cl2N2O. |
| Color | Slightly yellow to brown |
| Melting Point | 52.7℃ |
| Vapour Pressure | 0.158 mPa (20℃) |
| Boiling point | >340 ºC |
| Solubility | In water 0.18 g/l (pH 7.6, 20 ºC). In acetone, dichloromethane, ethanol, methanol, isopropanol, xylene, toluene, benzene >500, hexane 19 (all in g/l, 20 ºC). Also soluble in heptane and petroleum ether. |
| Stability | Very stable to hydrolysis in dilute acids and alkalis at room temperature, in the absence of light. Stable to temperatures up to 285 ºC. Stable to light under normal storage conditions. |
Imazalil is a fungicide of imidazole which has only one chiral carbon, shown in Fig 1, but in application, we just focus on despinner of imazalil with unstated stereochemistry.
Fig,1 Structure of imazalil
Imazalil, an antifungal postharvest agent, was initially introduced by Janssen Pharmaceutica in 1977. Since then, it has been consistently registered and utilized in various applications. In 1984, imazalil began to be used as a seed treatment, followed by its use in chicken hatcheries in 1990.
As with any fungicide, imazalil serves the purpose of safeguarding crops from disease and ensuring their ability to produce a profitable harvest. Today, imazalil remains instrumental as an agricultural aid, contributing to the preservation of crop integrity and maintaining high production output.
How Does Imazalil Work?
Imazalil is a systemic fungicide that exhibits both protective and curative properties. Its primary mode of action involves inhibiting demethylation in the biosynthesis of ergosterol, a sterol essential for maintaining the integrity of fungal cell membranes, much like cholesterol does in mammals.
When ergosterol is inhibited, the cell membrane becomes permeable and leads to leakage of intracellular contents. As a result, Imazalil effectively hinders fungal reproduction across a broad spectrum.
There are other active ingredients belonging to imidazole with the same action mode, such as triflumizole, pefurazoate and prochloraz etc.
Review of Global Registration and Use
We have checked the registration of imazalil around the world, as shown in the below table.
Table 2 Registration of Imazalil of The World
| Region | Type | Form | No. | Target | Pest. | Method |
| Australia | Formula. | Imazalil/Triadimenol+Imazalil | 3 | Barley Seed/Mushrooms | Green Mould/Net Blotch | / |
| Argentina | Tec. | 0.98 | 2 | / | / | / |
| 0.97 | 1 | / | / | / | ||
| Brazil | Tec. | 98% | 1 | / | / | / |
| 98.5 | 2 | / | / | / | ||
| Formula. | Imazacure 500 Ec | 1 | Banana/Hami Melon/Citrus | Antracnose | Drench | |
| Magnate 500 Ec | 1 | Melons | Antracnose | Drench | ||
| China | Tec. | 95% | 1 | / | / | / |
| 98% | 7 | / | / | / | ||
| Formula. | 15~22%Ew | 7 | Citrus/Banana/Grape Etc. | Green Mold | Drench | |
| 22.2~50%Ec | 13 | Citrus/Banana/Grape Etc. | Green Mold | Drench | ||
| Prochloraz+Imazalil Ew | 7 | Strawberry/Apple | Anthracnose | Drench/Spray | ||
| Imazalil+Fludioxonil Ew | 3 | Strawberry | Gray Mold | Spray | ||
| Egpyt | Formula. | Diabolo 10% Sl | 1 | Potato | Dry Rot | Spray |
| Eu | Formula. | Imazalil48+Ipconazole19 Me | 1 | Hordeum Vulgare | Ustilago | Drilling, Row |
| Imazalil 100ec | 1 | Rubus Idaeus | Ilyonectria | Drench | ||
| Usa | Tec. | 98% | 3 | / | / | / |
| Formula. | 14.~44.6 Ec | 7 | Citrus | Blue/Green Mold/Stem-End Rot | Drench | |
| Barley | Alternaria Leaf And Fruit Spot | Seed Treatment | ||||
| Hatchery Equipment | Aspergillus Fumigatus | Enclosed Premise Treatment | ||||
| 13.8EC | 1 | Hatchery Equipment | Aspergillus Fumigatus | Enclosed Premise Treatment | ||
| 74.25sc | 1 | Citrus | Blue/Green Mold/Stem-End Rot | Drench | ||
| Philippines | Formula. | Fungaflor 50l | 1 | Banana | Black Sigatoka /Black Leaf Streak | Spray |
| Fungaflor 75 Sp | 1 | Banana | Crown Rot Pathogens | Spray | ||
| Pakistan | Formula. | Imazalil 10%Sl | 1 | Seed Potato | Potato Silver Scurf | Spray |
Use on Crops
Imazalil is a highly effective fungicide that is utilized for the management of various fungal diseases on fruit, vegetables, and ornamentals. It provides excellent control against powdery mildews on cucurbits and ornamental plants, as well as roses.
Additionally, imazalil is particularly valuable in preventing storage diseases caused by pathogens such as Penicillium, Gloeosporium, Phomopsis, and Phoma spp. This versatile compound plays a significant role in safeguarding the quality and longevity of citrus fruit, pome fruit, bananas, and seed potatoes.
The recommended application rates are as follows: for seed treatment, it is advisable to use 4-5 grams per 100 kilograms of seeds; for ornamentals and vegetables, the range is between 5 and 30 grams per hectoliter; and for post-harvest treatment, a dosage of 2-4 grams per metric ton of fruit is sufficient.
Citrus
The antifungal agent imazalil is commonly used on citrus fruits and is registered almost all over the world. It is used to control green mould in citrus by drench. Here are the excellent effects on the fresh rate of green orange in table 3.
Table 3 Effects of fungicides on fresh rate of Hainan green orange
| Treatment | Storage Time/ d | |||||
| 13 | 16 | 19 | 22 | 25 | 28 | |
| Control | 97.4 | 96.2 | 84.1 | 81.6 | 74.6 | 61.4d |
| Carbendazim250 | 98.1 | 96.8 | 90.9 | 87.0 | 80.6 | 72.1c |
| Carbendazim500 | 97.4 | 94.8 | 89.1 | 84.9 | 76.9 | 69.9c |
| Thiophanate methyl 250 | 99.4 | 95.6 | 91.9 | 90.6 | 85.6 | 83.8b |
| Thiophanate methyl 500 | 100.0 | 98.8 | 95.6 | 91.2 | 86.2 | 84.4b |
| Imazalil 500 | 98.8 | 98.8 | 96.9 | 93.9 | 88.9 | 87.7b |
| Imazalil 1000 | 100 | 99.4 | 98.2 | 96.3 | 93.3 | 93.3a |
In postharvest citrus fruit treatment, the use of this product can greatly enhance the appearance of the fruit. It adds a beautiful shine, prevents weight loss, and slows down the aging process by reducing transpiration and providing protection against decay-causing fungi such as Penicillium and Diploida.
This product can be used in conjunction with other imazalil products at various stages of harvest, storage, and packaging. However, it is important to note that no more than two applications of imazalil can be made to any single batch of citrus fruit.
The recommended post-harvest interval (PHI) for this citrus product is 14 days, and the fruit can only be used once. It is advisable to treat the citrus within 24 hours of harvesting by soaking it for 2 minutes, drying it, and storing it. After a period of 14 days, the fruit can then be marketed.
If you need to store the citrus for a short term before sale, dilute the liquid 1400 times and soak the fruit for 2 minutes. For citrus that has been stored for more than three months, dilute the solution 1000 times and soak the fruit for 2 minutes. In regions where acid rot or wet collapse is prevalent, it is recommended to soak the fruit for 2 minutes.
Fig.2 Green mold of cirtus
Seed Dressing
Imazalil serves as a seed dressing agent, specifically targeting diseases such as Fusarium and Helminthosporium spp. in cereals. Since its introduction as a seed treatment in 1984, imazalil has been instrumental in reducing crop loss caused by disease, with barley being a primary focus.
Its effectiveness has led to its registration for seed dressing in both the USA and Australia. Imazalil 500EC is an effective treatment option for controlling barley leaf rust through seed treatment protocols.
Fig.3 Barley leaf rust
Hatchery Equipment
This product is highly effective for controlling Aspergillus organisms in poultry and turkey hatchery equipment that has been thoroughly cleaned. Before introducing the eggs, it can be applied to empty hatchery cabinets, setters, coolers, storerooms, and handling equipment.
It’s important to note that Imazalil 13.8 ec should not be used when eggs and poultry are present. By using Imazalil 13.8 EC, the levels of Aspergillus organisms and spores in treated areas can be significantly reduced.
A concentration of 0.15% active ingredient should be provided for antifungal purposes. The diluted product should be applied using spray devices directly to areas such as walls, floors, and equipment.
It is essential to ensure the cleanliness of the area or equipment being treated and to seal it off from outside air currents prior to treatment in order to achieve optimal effectiveness. Before treating ventilation ducts, fans should be shut off.
Fig.4 Hatchery Equipment
Find Supplier
If you want to guarantee the quality and price of Imazalil, it is important to choose a manufacturer rather than a trading company. For more information call +86 (0)577 55882935 or email info@hb-p.com for a free sample.
