Downy Mildew Chemical Control | Chlorothalonil 10% + Cymoxanil 10% FU

Product Specifications

Chlorothalonil 10% + Cymoxanil 10% FU consists of two active ingredients and is formulated as a fumigant. Buyers should pay particular attention to verifying the active ingredient content, formulation, batch quality documents and the scope of registration in the target market.

Technical Parameters	Product Specifications
Product Name	Chlorothalonil 10% + Cymoxanil 10% FU
Active Ingredient 1	Chlorothalonil 10%
Active Ingredient 2	Cymoxanil 10%
CAS Number 1	1897-45-6
CAS Number 2	57966-95-7
Chemical Family 1	Chloronitrile
Chemical Family 2	Cyanoacetamide-oxime
FRAC Group	M05 + 27
Formulation	FU (Smoke Generator)
Product Category	Fungicide
Main Target Disease	Downy Mildew
Scope of Application	Subject to the locally registered label
Quality Standard	Subject to the actual product specifications
Shelf Life	Subject to the product label and stability data
Storage Conditions	As per the product label and SDS

Downy Mildew: Disease Identification and Risk Factors

Downy mildew is a group of plant diseases caused by oomycetes and is not classified as a true fungal disease. Downy mildew on different crops may be caused by different pathogens; therefore, the selection of control products must be based on the specific crop and pathogen in question.

Common Symptoms

Typical symptoms of downy mildew may include:

• Pale yellow to yellowish-brown lesions on the upper leaf surface, some confined by leaf veins.
• Under high humidity, spore structures in greyish-white, greyish-purple, or other colours may appear on the underside of leaves.
• As the disease progresses, lesions may enlarge and coalesce, leading to necrosis of leaf tissue.
• In severe outbreaks, the disease may impair leaf function, plant growth and marketable quality.

Symptoms vary between crops and pathogens; therefore, you cannot determine the disease type from a single symptom alone.

Environmental Conditions That Favour Disease

In some downy mildew infection systems, high humidity, prolonged leaf wetness, inadequate ventilation and dense plant canopies may favour disease development.

In protected cultivation, night-time dew, inappropriate irrigation timing, and insufficient air circulation can all make disease management more difficult.

Therefore, downy mildew management should not rely solely on fungicides but should also incorporate humidity control, ventilation, field hygiene and disease monitoring.

Mode of Action: Chlorothalonil + Cymoxanil

This combination formulation contains two active ingredients with different modes of action; however, it cannot be assumed that, simply because they are combined, they will provide the same level of protection against all downy mildew pathogens.

Chlorothalonil — FRAC Group M05

Chlorothalonil is a multi-site contact protective fungicide.

Its primary mode of action is to protect at the site of deposition by interfering with multiple physiological processes in susceptible pathogens. Owing to its multi-site mode of action, Chlorothalonil plays a distinct role in resistance management compared to many single-site fungicides.
However, its actual performance remains dependent on deposit coverage, application conditions, pathogen susceptibility and the registered uses of the product.

It is not a systemic fungicide capable of penetrating plant tissues to treat all established lesions.

Cymoxanil — FRAC Group 27

Cymoxanil belongs to FRAC Group 27 and shows both local and systemic activity, as well as efficacy against early infection stages.

When used according to product instructions, it can help inhibit the development of early infections caused by susceptible oomycetes.

However, the actual control efficacy of cymoxanil is influenced by the timing of application, pathogen susceptibility and specific product usage conditions. It should not be promoted as capable of eliminating all established lesions, nor should it be claimed effective at any stage after infection.

How the Combination Works

The two active ingredients have different modes of action:

• Chlorothalonil primarily provides contact protection.
• Cymoxanil exhibits local systemic activity and controls infection in the early stages.
• The actual efficacy of the formulated product must still be assessed in conjunction with the target pathogens, application conditions and product quality.

It cannot be claimed that the product will necessarily provide a longer residual effect, more comprehensive disease control or a lower risk of resistance simply because the two active ingredients have different modes of action.

For further information on single-ingredient Cymoxanil products, please refer to the Cymoxanil Fungicide page.

FU Formulation Characteristics

FU stands for ‘Smoke Generator’ in the pesticide formulation coding system. These formulations typically release smoke containing the active ingredient via a specified ignition method, which differs from the application method of conventional spray formulations.

Smoke Dispersion and Deposition

Smoke can disperse within a suitable space, but the final deposition pattern is not entirely uniform.

Actual performance may be influenced by the following factors:

• The facility’s internal structure and spatial layout.
• Airflow direction and air exchange rates.
• Plant density and canopy structure.
• Product placement and method of application.
• Operating conditions specified on the product label.

Consequently, smoke dispersion cannot be equated with uniform coverage of every leaf, nor can it guarantee that the same amount of active ingredient will be deposited on both the upper and lower surfaces of the leaves.

Differences from Conventional Spray Formulations

There are differences in application methods between FU smoke generators and conventional spray formulations.

Depending on the specific product label, FU products generally do not require preparing a spray solution in the conventional manner, nor do they rely on conventional spraying equipment.

However, this does not imply that they are more effective than spray formulations in all scenarios, nor does it justify claims of zero drift, zero residue deposition or the complete absence of under-coverage.

Application and Operator Safety

Because FU products involve ignition and smoke release, strictly adhere to the relevant product’s operating label and SDS.

During actual use, ensure that:

• Ignition and placement methods comply with the product label.
• Personnel and other non-target organisms leave the treatment area as the label requires during treatment.
• The prescribed ventilation and re-entry interval (REI) are observed.
• Store unused product in accordance with the safety documentation, and keep it away from inappropriate heat sources and ignition sources.
• Treatment residues and packaging are disposed of in accordance with local regulations.

This page does not provide general guidelines on application rates, application spacing or treatment duration; these parameters should be determined by consulting the actual product label.

Application Scenarios and Target Crops

The pathogen, epidemiological characteristics and crop susceptibility of downy mildew vary. Even if a particular crop is frequently affected by downy mildew, this does not mean this product is registered for use on that crop.

Protected-Crop Applications

The following categories of crops in protected cultivation may involve downy mildew management; they illustrate relevant application scenarios and do not imply that this product has been approved for use on all of these crops.

Crop Category	Examples	Confirmation Required
Cucurbits	Cucumber, Melon and other cucurbits	Check crop, pathogen and product registration
Leafy Greens	Lettuce, spinach and other leafy vegetables	Check specific crops and authorised uses
Herbs	Basil, parsley, coriander, etc.	Check crop registration and residue requirements
Allium Crops	Onions and other Allium crops	Check pathogens and scope of registration
Nursery Crops	Specific seedling and propagation facilities	Check facility uses and labelling restrictions

Target Pathogens

Downy mildew can be caused by various oomycete pathogens, such as certain species of the genera Pseudoperonospora, Bremia and Peronospora.

These pathogens have specific relationships with different crops; therefore, control results from one crop cannot be directly extrapolated to all cases of downy mildew.

Determine whether a product is suitable for a particular pathogen based on the product’s registered scope and efficacy data.

Application Timing

Downy mildew management typically requires the combination of disease risk, crop growth stage and disease monitoring to determine control strategies.

However, this page does not provide uniform recommendations for all crops on preventive application timing, treatment regimens at disease onset, or intervals between repeat applications.

Specific application periods, frequency, dosage and safety intervals should all comply with the approved label of the corresponding product.

Resistance Management and IPM Integration

Resistance management should be conducted in conjunction with the active ingredients’ modes of action, pathogen susceptibility, registered uses, and non-chemical management measures.

Chlorothalonil belongs to FRAC Group M05, whilst Cymoxanil belongs to FRAC Group 27. Although the two active ingredients have distinct modes of action, this does not mean that other resistance management measures are unnecessary when using this formulated product.

Fungicide Rotation

Resistance management must account for the susceptibility of target pathogens to different active ingredients.

It is recommended to rotate products that are effective against the target pathogens and have appropriately different modes of action, based on local registrations, FRAC resistance management guidelines and actual disease conditions.

One should not assume that two products will necessarily control the same pathogen effectively simply because their FRAC codes differ.

At the same time, adhere to the number of applications and intervals specified on the label to avoid unreasonable repeated use of products with the same mode of action.

Greenhouse IPM Practices

In protected cultivation, the following management measures help to reduce the risk of downy mildew:

• Humidity Management: Manage humidity and night-time dew formation appropriately.
• Ventilation: Improve air circulation according to greenhouse conditions.
• Irrigation Timing: Schedule irrigation to minimise prolonged leaf wetness.
• Canopy Management: Control planting density appropriately to improve canopy ventilation.
• Sanitation: Promptly remove infected tissue and plant debris.
• Crop Monitoring: Regularly inspect both sides of the leaves and monitor disease progression.
• Planting Material: Use healthy seedlings and varieties suited to local growing conditions wherever possible.

For further information on disease management for different crops, please refer to Crop Disease Management Solutions.

Chemical control and environmental management should be used in conjunction; one should not rely on a single product to resolve all downy mildew issues.

Compliance and Safety

Verify product registration, authorised crops, target diseases, and safety requirements separately for each target market.

Regulatory Status

The European Union has decided, under Commission Implementing Regulation (EU) 2019/677, not to renew authorisation for the active substance chlorothalonil.

This Regulation stipulates that authorisations for relevant plant protection products must be withdrawn by 20 November 2019 at the latest, with the transitional grace period ending on 20 May 2020 at the latest.

Consequently, this product containing Chlorothalonil should not be promoted as a plant protection product currently authorised for routine use in the EU.

For markets outside the EU, local regulations, product registrations, authorised crops and residue requirements must be verified on a case-by-case basis; the approval status in one country cannot be directly applied to other countries.

Product Label and Use Restrictions

Prior to purchase and use, please confirm:

• Whether the target country permits the relevant active substance and formulation.
• Whether the product has the corresponding registration or legal basis for use.
• Approved crops, diseases and methods of application.
• Personal protective equipment, ventilation and re-entry intervals specified on the label.
• Relevant pre-harvest intervals, residue limits and other restrictions on use.

If local regulations do not permit the sale or use of the relevant product, do not introduce the product into that market solely on the basis of the active ingredient’s technical characteristics.

Personnel and Environmental Safety

FU smoke-generating agents involve smoke release and ignition operations; safety management must be carried out in accordance with the specific product label and SDS.

Compliance with general operating principles alone does not guarantee that the product poses no risk to all personnel, non-target organisms or the environment.

Appropriate personal protective equipment should be used in accordance with the actual hazard classification, and the prescribed requirements for isolation, ventilation, re-entry and waste disposal must be implemented.

Quality Control and Technical Documentation

For Chlorothalonil 10% + Cymoxanil 10% FU, purchasers should focus on verifying the active ingredient content, formulation identity, batch quality and packaging integrity.

Key Quality Checks

Quality Item	Procurement Focus
Active Ingredient Content	Verify the nominal content and test results for both active ingredients
Product Identity	Verify that the formulation is the FU fumigant
Batch Consistency	Verify that batch quality complies with the actual product standards
Physical Condition	Inspect appearance and relevant physical parameters in accordance with product specifications
Packaging Integrity	Verify packaging integrity and suitability for transport
Storage Stability	Subject to actual stability data
Batch Traceability	Verify batch numbers and production records
Technical Documentation	To be confirmed based on the documentation actually available

COA, SDS and TDS

The COA is used to detail the test results for the corresponding batch; the SDS is used to provide information on product hazards, operational precautions, storage and emergency response; the TDS is used to specify the technical parameters of the actual product.

The purchaser should verify that the relevant documents correspond to the actual product supplied.

If the target market requires specific stability reports, registration dossiers, or other technical documentation, confirm the scope of what can be provided before procurement. General production capacity should not be equated with testing or validation already completed for a specific batch.

Packaging and Bulk Supply

POMAIS offers professional product supply partnerships to pesticide importers, distributors, wholesalers, brand owners and registration companies.

For Chlorothalonil 10% + Cymoxanil 10% FU, packaging, labelling, documentation, and order arrangements must be confirmed in accordance with the actual product specifications and the target market’s requirements.

Packaging and Labelling Requirements

The following may be discussed based on the actual order:

• Packaging specifications and outer carton labelling.
• Labelling languages required by the target market.
• Batch number, production date and product traceability information.
• Relevant quality documentation and transport information.
• Applicable trade terms and delivery arrangements.

Customised labelling and packaging must comply with the actual product specifications, registered uses, and local regulations; they do not substitute for product registration.

Commercial Terms

Item	Confirmation
Minimum Order Quantity	Subject to confirmation based on actual FU units and consolidated order quantities
Lead Time	To be confirmed following verification of product, packaging and compliance requirements
Trade Terms	To be confirmed based on destination and order conditions
Technical Documents	Subject to the actual documentation available
Registration Support	To be confirmed based on target market requirements and the scope of documentation actually available

Frequently Asked Questions

What Is Chlorothalonil 10% + Cymoxanil 10% FU?

This is a combined fungicide containing Chlorothalonil and Cymoxanil, formulated as a FU (Smoke Generator). It is primarily positioned for downy mildew management. Specific uses depend on the product registration label.

What Does FU Mean in Pesticide Formulations?

FU stands for ‘Smoke Generator’. These formulations typically release smoke containing the active ingredients via a specified ignition method, unlike conventional spray formulations.

How Do Chlorothalonil and Cymoxanil Work?

Chlorothalonil belongs to FRAC Group M05 and is a multi-site contact protective fungicide; Cymoxanil belongs to FRAC Group 27 and shows local systemic activity and efficacy against early infection stages. Actual efficacy depends on pathogen susceptibility, application conditions and the authorised uses specified on the product label.

Which Crops Can This Product Be Used On?

The specific range of crops depends on the product’s registration status in the target country. Cucurbits, leafy vegetables, herbs, and certain Allium crops may require downy mildew management; however, these crop categories should not be regarded as a list of crops for which this product is authorised.

Does FU Smoke Guarantee Complete Leaf Coverage?

This cannot be guaranteed. The smoke will disperse within the appropriate space, but final deposition is influenced by the structure of the facility, air flow, plant density and arrangement. It cannot therefore be claimed that every leaf receives uniform coverage.

Does This Product Leave No Residue?

No such assurance can be given. Determine the presence of active ingredient deposition or residues based on the actual product, method of application, analytical data, and applicable regulations. Harvest intervals and residue requirements must comply with the relevant registered label.

Can This Product Be Mixed with Other Fungicides?

FU smoke generators differ from conventional spray formulations and cannot be used directly in a spray tank. Any scheme involving combination with other products must be supported by the relevant label and technical justification; products should not be mixed without prior confirmation.

What Technical Documents Can Buyers Request?

Purchasers may request a Certificate of Analysis (COA), Safety Data Sheet (SDS), Technical Data Sheet (TDS) and other technical documents in accordance with project requirements. Confirm the availability of specific documents before purchase, based on the actual product and the target market’s requirements.

Is Chlorothalonil Approved in the European Union?

The European Union has decided not to renew the approval of the active ingredient Chlorothalonil; the authorisation for relevant plant protection products has been revoked and the transitional grace period has ended. The approval status in other markets must be verified separately.

Request Product Specifications and Quotation

If you are evaluating Chlorothalonil 10% + Cymoxanil 10% FU, POMAIS can discuss product specifications, quality documentation, packaging and export cooperation arrangements based on actual supply conditions.

We primarily serve pesticide importers, distributors, brand owners and registration companies, supporting professional procurement clients in product evaluation and supply partnerships.

To facilitate the confirmation of specific requirements, please provide:

• Destination Country: Target import country.
• Required Product: Chlorothalonil 10% + Cymoxanil 10% FU.
• Registration Status: Registered, under registration or pending evaluation.
• Target Crop and Disease: Target crop and downy mildew management requirements.
• Packaging Requirements: Packaging capacity, labelling language and related requirements.
• Expected Purchase Volume: Estimated purchase quantity.
• Technical Documents: Required COA, SDS, TDS and other documentation.
• Delivery Requirements: Expected procurement and delivery arrangements.

We will further confirm a viable procurement partnership based on actual product specifications, available documentation, supply conditions and target market regulations.

Contact POMAIS for Product Specifications