What is the difference between seed-treatment fungicides and insecticides? How should you choose between them?

Seed-treatment fungicides are primarily used to manage specific seed-borne and soil-borne pathogens, while seed-treatment insecticides mainly target soil-dwelling pests and certain insects that damage seedlings in the early stages. Although both are applied to seeds before planting, they address entirely different issues.

For example, fludioxonil and metalaxyl-M can be used for seedling disease management within their respective registration scopes, while thiamethoxam is primarily used for the control of specific early-stage insects. Fungicides cannot replace insecticides in addressing feeding damage caused by pests, nor can insecticides replace fungicides in controlling seed rot caused by pathogens such as Pythium.

So why are there still so many combined seed treatment products on the market that contain both insecticides and fungicides?

The reason is simple: some crops may indeed face threats from both pathogens and pests during the seedling stage. However, not every region or crop requires dual protection.

To make the right product choice, one should first understand the specific risks present in the local area before deciding whether to use a fungicide, an insecticide, or a combined insecticide-fungicide product. For pesticide importers and distributors, this assessment also impacts product registration, formulation selection, seed treatment costs, and whether there is overlap in their existing product lines.

What is the main difference between seed treatment fungicides and insecticides?

The most fundamental difference between the two lies in their targets.

The primary function of seed treatment fungicides is to reduce losses caused by specific pathogens during seed germination and the early seedling establishment stage.

Seed treatment insecticides, on the other hand, primarily target certain insects in the soil surrounding the seeds, as well as pests that may cause damage during the early stages of crop emergence.

The two are not interchangeable, and their scope of control should not be determined solely based on their trade names.

Comparison of Seed Treatment Fungicides and Insecticides

Comparison Criteria	Seed-Treatment Fungicides	Seed-Treatment Insecticides
Primary Targets	Specific fungal and oomycete pathogens	Specific insect pests
Primary Risks	Seed rot, damping-off, and certain seedling root rot diseases	Feeding by soil-dwelling pests and damage from certain early-stage sucking pests
Common Active Ingredients	Fludioxonil, Metalaxyl-M, Difenoconazole, Azoxystrobin	Thiamethoxam, Imidacloprid, Clothianidin
Classification by Mode of Action	FRAC Group	IRAC Group
Typical Protection Stages	Seed Germination and Early Seedling Establishment	Early Stages of Seed and Seedling Damage
Can It Control Risks from Another Category?	No	No
Selection Criteria	Local pathogen species and disease risk	Local pest species and early outbreak risk
Does it guarantee increased yield?	Not guaranteed	Not guaranteed
Must it be mixed with other products?	Not necessarily	Not necessarily

This table helps us understand product classifications, but when actually making a purchase, it is necessary to further confirm the specific control scope of each active ingredient.

This is because even among fungicides, not all products are effective against the same pathogens.

Similarly, thiamethoxam and other seed-treatment insecticides cannot be assumed to have the same efficacy against all soil-borne and seedling-stage pests.

For further information on the functions and limitations of seed treatment itself, please refer to SunAgro’s Seed Treatment Benefits for more information.

What diseases do seed-treatment fungicides primarily protect seeds against?

From the moment seeds are sown into the soil until healthy seedlings emerge, they must undergo processes such as water absorption, germination, root formation, and emergence.

During this stage, seeds and seedlings may be infected by various pathogens.

Some of these pathogens originate from the surface or interior of the seed, while others are present in the soil.

If the infection is severe, the following may occur:

• Seed rot before emergence;
• Infection of the radicle or young roots;
• Damping-off after seedlings emerge;
• Inhibited root growth;
• Uneven emergence in the field;
• A reduction in the number of viable plants ultimately produced.

The value of seed-treatment fungicides lies in providing targeted protection early on against these risks, rather than guaranteeing that all seeds will germinate successfully.

What is the difference between seed-borne and soil-borne pathogens?

Seed-borne pathogens may be present on the seed surface, within the seed coat, or inside the seed.

As the seed germinates, the pathogen may infect the growing tissue.

Soil-borne diseases primarily originate from the soil environment surrounding the seeds.

For example:

• Fusarium
• Rhizoctonia
• Pythium
• Phytophthora

All of these may be associated with seedling-stage diseases in various crops.

However, these pathogens do not belong to exactly the same biological category, nor do they exhibit the same susceptibility to pesticides.

Among them, Pythium and Phytophthora are oomycetes, not true fungi.

Therefore, when selecting a seed-treatment fungicide, one cannot simply assume that any fungicide is suitable just because the label mentions “Seed Rot” or “Damping-off.”It is even more important to confirm:

What exactly is the pathogen causing the disease? Does the active ingredient you intend to purchase have the appropriate registered uses and control efficacy?

Why do Fludioxonil and Metalaxyl-M often appear in the same formulation?

These two active ingredients have different modes of action and target different primary pathogens.

Fludioxonil belongs to FRAC Group 12.

Within its approved registration scope, it can be used to manage certain seed-borne, seed-surface, and soil-borne fungal diseases, such as specific risks associated with Fusarium and Rhizoctonia.

Metalaxyl-M belongs to FRAC Group 4.

It is primarily used to manage certain oomycete pathogens, such as Pythium and Phytophthora, within the scope of its registration.

This means that the combination of the two is not simply a matter of increasing the number of fungicides, but rather of having different active ingredients perform distinct pathogen management functions.

For example, SunAgro’s Fludioxonil 25 g/L + Metalaxyl-M 10 g/L FS falls under this category of dual-fungicide seed treatment products.

However, even when two FRAC Groups are combined, the product cannot be claimed to control all seed and seedling-stage diseases.

The final scope of control must still be determined based on the target crop, pathogen types, product registration, and actual treatment conditions.

Under what circumstances is fungicidal seed treatment worth considering?

Fungicidal seed treatment may offer significant value in markets that frequently face the following issues:

• A history of frequent seed rot or seedling diseases;
• Persistently low soil temperatures or excessive soil moisture during planting;
• A high risk of seed-borne pathogens in some seeds;
• Slow crop emergence, making seedlings susceptible to infection;
• Pathogens that require management through seed treatment have been clearly identified locally.

However, it is important to note:

Low temperatures and high humidity are merely environmental factors that may increase the risk of certain diseases; they do not directly prove the presence of a specific pathogen.

If the seeds themselves have lost viability, or if the soil is chronically waterlogged, fungicides cannot resolve all germination issues.

What early-stage pests are seed-treatment insecticides primarily used to control?

Unlike fungicides, seed-treatment insecticides target insects.

Some pests feed on seeds, young roots, or underground stems before or after seed germination.

Others damage leaves or suck plant sap after seedlings emerge from the soil.

If local pest occurrence patterns are well-defined and the product has the appropriate registered uses, seed-treatment insecticides can serve as a method for managing early-stage insect pests.

However, seed-treatment insecticides do not constitute a comprehensive pest management strategy for the entire growing season.

Why do soil-dwelling pests require separate consideration?

Soil-dwelling pests may have already caused damage before farmers even notice a problem.

For example, in some markets, attention should be paid to:

• Wireworms
• Seedcorn Maggots
• Certain other soil-feeding insects

These pests can damage seeds, radicles, or the underground tissues of seedlings.

Symptoms of damage may resemble those of certain seedling-stage diseases.

For example, missing plants or slow plant growth may also occur in the field.

However, the causes are different, and the management approaches are entirely different.

If missing plants are caused by soil-dwelling pests, adding a fungicide will not solve the problem of insect feeding.

Similarly, just because a particular seed-treatment insecticide can manage one type of soil-dwelling pest does not mean it can control all soil-dwelling pests.

Can seed-treated insecticides also control post-emergence pests?

Certain active ingredients with systemic activity may be used, under conditions permitted by their registration, to manage specific early-stage sucking pests or other seedling-stage pests.

For example:

Thiamethoxam belongs to IRAC Group 4A.

It can be used for the management of corresponding early-stage insects in some registered crop seed treatment systems.

However, whether it can effectively control the following pests:

• Aphids
• Thrips
• Flea Beetles
• Other seedling-stage insects

depends on the crop, the target pest, the treatment rate, product registration, and local pest susceptibility.

The fact that thiamethoxam is systemic should not be used to claim that it provides continuous control of these pests throughout the entire growing season.

SunAgro’s Thiamethoxam 600 g/L FS is a practical example of a seed treatment product containing a single active insecticidal ingredient.

Why doesn’t early pest control equal protection throughout the entire growing season?

Because seed treatment products are primarily applied to seeds, the scope and duration of protection they provide are influenced by many factors.

For example:

• The active ingredient and its properties;
• The registered application rate;
• Seed size;
• Crop growth rate;
• Soil moisture;
• Soil conditions;
• Pest emergence timing;
• Pest susceptibility.

As the crop grows, the actual level of protection provided by seed treatments may gradually decline.

Therefore, distributors should not treat seed-treated insecticides as a substitute for later-stage field monitoring and necessary pest control measures.

For some pests that primarily occur during the mid-to-late stages of crop growth, seed treatments may not even be an appropriate product strategy.

When should you choose a fungicide, insecticide, or a combined seed treatment?

This is the most important question to consider when selecting a seed treatment product.

Let’s set aside brand, formulation, and concentration for now and focus solely on the specific issues in the local market.

Four Common Risk Scenarios

Local Growing Conditions	Product Types to Prioritize	Reason
Diseases frequently occur during the seedling stage; early-season insect pests are less common	Fungicide seed treatment	The primary risk comes from pathogens
Recurring early-season insect pests, with low disease risk or existing adequate disease protection	Insecticidal seed treatment or supplemental insecticide solution	The primary new demand comes from insects
Clear risks exist for both diseases and early-season insect pests	Combined insecticide and fungicide treatment	Both types of biological risks require management
Unclear incidence of diseases and pests	Assess risks first	Avoid increasing treatment costs without justification

This is a product selection framework, not a globally standardized seed treatment prescription.

Even in markets with the same crops, completely different treatment strategies may be required due to variations in climate, soil, crop rotation, historical pest and disease history, and agricultural management practices.

Scenario 1: The primary issues are seed rot and seedling damping-off

Assume that a particular growing region has experienced the following for multiple consecutive seasons:

Seed rot after sowing, uneven emergence, or seedling damping-off.Local records indicate that these issues are associated with specific seed-borne or soil-borne pathogens.

In this situation, priority should be given to evaluating fungicidal seed treatment products targeting the relevant pathogens.

Whether an insecticide should be added simultaneously depends on whether there are significant early-stage insect risks in the area that warrant management.

If there are no clear insect problems, adding an insecticide merely to make the product appear more comprehensive may not necessarily provide additional value.

Scenario 2: The primary issues are soil-dwelling pests

Suppose local seed quality, planting practices, and disease management are relatively stable, but some corn fields frequently experience feeding damage from soil-dwelling insects.

In this case, a more reasonable approach might be to evaluate seed treatment insecticides with registrations for the relevant pests.

However, if the market already employs other effective seed fungicide treatment regimens, the introduction of a new insecticide requires consideration of how it will integrate with the existing treatment system.

This involves:

• Product registration;
• Treatment process;
• Dosage;
• Physical compatibility;
• Seed safety;
• Total cost.

It is not advisable to simply recommend that customers directly mix two different seed treatment (FS) products.

Scenario 3: Early-season losses caused by both diseases and pests

This scenario represents one of the clearest applications for combined insecticide-fungicide seed treatment products.

For example, a market may face both persistent seedling-stage disease risks and problems with soil-dwelling pests or early-season sucking pests.

If appropriate active ingredients can be identified and the combination product obtains local registration, the formulation can integrate both types of protection into a single seed treatment process.For example:Thiamethoxam + Metalaxyl-M + FludioxonilIn which:

• Thiamethoxam is responsible for early-stage insect management within the scope of the registration;
• Metalaxyl-M primarily manages certain oomycete pathogens;
• Fludioxonil is responsible for managing the corresponding fungal diseases.

Each active ingredient should have a clearly defined function.

A truly meaningful formulation is not simply about increasing the number of ingredients, but about ensuring they collectively address the various risks that actually exist in the market.SunAgro’s Thiamethoxam 22.2% + Metalaxyl-M 1.7% + Fludioxonil 1.1% FS is an example of this type of formulation.

Scenario 4: Uncertain whether poor seedling emergence is caused by pests or diseases

This situation is not uncommon in actual production.

When farmers see missing plants in the field, their first reaction might be:

“The seed treatment didn’t work.”However, missing plants are not necessarily caused by disease or pests.

Other possible causes include:

• Low seed germination rate;
• Improper seed storage;
• Inappropriate seeding depth;
• soil compaction;
• severe waterlogging;
• drought;
• abnormal temperatures;
• issues with seeding machinery.

If the cause has not been determined, immediately recommending a combination product with a higher concentration or more active ingredients may not solve the problem.

Product selection should begin with a diagnosis, not with a quote.

Are insecticide-fungicide combination seed treatments always better than single-component treatments?

Not necessarily. The primary value of combination products lies in integrating different protective functions, not in guaranteeing greater efficacy than single-component treatments in all situations. For distributors, whether it is worthwhile to add combination products to their product line should be evaluated based on four factors.

First, does the market truly need dual protection?

This is the most fundamental question.

If customers are already achieving good disease control through existing management practices and early-season pest outbreaks are rare, then adding an insecticidal ingredient may not yield returns commensurate with the cost.

Conversely, if the market experiences persistent losses from both diseases and pests, combination products may offer clearer commercial value.

Therefore, combination products cannot justify their value solely on the basis of “broader protection”; they must also demonstrate that the added protection is genuinely needed by the market.

Second, do the added active ingredients have clearly defined roles?

For example:

Difenoconazole, Fludioxonil, and Thiamethoxam can form:

• Difenoconazole: FRAC Group 3
• Fludioxonil: FRAC Group 12
• Thiamethoxam: IRAC Group 4A

This indicates that the formulation contains two fungicidal modes of action and one insecticidal mode of action.

However, not all pathogens are susceptible to these two fungicides, nor can all insects be controlled by thiamethoxam.

Therefore, the ultimate value of the combination must be assessed based on the local target pests and diseases.

It is also important to note a common point of confusion:FRAC Group 4 and IRAC Group 4A are not the same classification of modes of action.FRAC is used for fungicide resistance management, while IRAC is used for insecticide resistance management. One cannot assume that they share the same mode of action simply because their numbers are similar.

Third, is the formulated mixture suitable for the target seeds?

If a product needs to contain multiple active ingredients, in addition to biological activity, it is also necessary to consider whether the formulation can be produced and used stably.For example:

• Concentrations of different active ingredients;
• Suspension stability;
• Particle size and dispersion properties;
• Viscosity;
• Seed coverage and adhesion;
• Compatibility with treatment equipment;
• Germination and seed vitality;
• Storage stability.

For FS products, formulation quality and seed treatment performance are crucial foundations for commercialization.

Even if the three active ingredients each have clearly defined control applications, this does not directly guarantee that their combination product will be suitable for every type of crop seed.

Fourth, can the formulated product reduce overall application complexity?

In some specialized seed processing systems, a formulated product with a pre-designed, optimized formulation may help simplify product preparation, metering, and management processes.

However, this advantage must be grounded in actual processing practices.

For example:

If a local seed company already has a mature fungicide treatment process, but there is demand for insecticides only among certain customers, it may be more flexible to retain separate fungicide and insecticide products.

Therefore, importers should not assume that:

pre-mixed formulations are necessarily more convenient than single-component solutions, nor should they assume that all single-component products are suitable for on-site mixing.

Ultimately, factors such as registration status, equipment, treatment processes, and economic costs should be compared.

How should seed treatment products be selected for wheat, corn, soybeans, and cotton?

There are significant differences among crops in terms of seeds, pests and diseases, and treatment channels.

Therefore, even when using the same active ingredient, the registered application rates and treatment methods for other crops cannot be directly replicated.

Key Evaluation Criteria for Different Crops

Crop	Common Early-Stage Disease Risks	Common Early-Stage Pest Risks	Key Considerations for Product Selection
Wheat	Certain seed-borne diseases, seedling rot, and root diseases	Certain soil-dwelling pests, early-season aphids	Pathogen types, seed health, and early-season pest outbreaks
Corn	Seed rot, seedling damping-off, and certain root diseases	Wireworms, seedcorn maggots, etc.	History of soil-dwelling pests and early-season disease risks
Soybeans	Diseases caused by Pythium, Phytophthora, Rhizoctonia, Fusarium, etc.	Certain seed and seedling pests	Soil conditions, history of diseases, and economic risks from early-season pests
Cotton	Partial seed rot, damping-off, and seedling-stage diseases	Thrips, certain soil-dwelling pests	Seedling growth rate, pest pressure, and treatment regimens
Rice	Specific diseases associated with local seeds and seedlings	Early-season pests within the scope of local registrations	Cultivation methods, seed treatment processes, and registration status

The pathogens and pests listed in the table represent areas of market evaluation and do not imply that any product has been approved for use on these crops.

Wheat: Why Is Assessing Seed-Borne Diseases Important?

Seed treatment for wheat and other cereal crops often requires a focus on specific seed-borne pathogens and early-stage seedling diseases.

If economically significant early-stage insect damage is present locally, insecticide supplementation strategies can be further evaluated.

However, not all wheat markets should be defined as requiring the use of combined insecticide-fungicide products.

What really matters is:

Whether there is a clear pathogen risk to local seeds, and whether insects cause economic damage in the early stages that warrants management.

Corn: Soil-dwelling Pests and Early-Stage Diseases Require Separate Assessment

When corn seeds germinate in the soil, they may face both pathogen infection and feeding by soil-dwelling insects simultaneously.

However, the primary concerns may vary significantly from region to region.

In some regions, seed rot and seedling diseases warrant greater attention.

In other regions, there may be persistent problems with soil-dwelling pests such as wireworms.

If both types of risks are clearly present, combination products may offer practical value.

However, just because corn is a field crop does not mean a one-size-fits-all insecticide-fungicide combination formulation should be used.

Soybeans: Not Every Field Needs Additional Insecticide Treatment

This is an example that distributors should take the time to understand thoroughly.

In its 2026 update to the soybean seed treatment guidelines, the U.S. Crop Protection Network notes that fungicide seed treatments are more likely to demonstrate value in fields with higher disease risk.

For insecticidal seed treatments, greater emphasis should be placed on actual pest pressure, historical records, and economic returns.

In some soybean markets, if early-season insect damage is low, the economic benefits of an additional insecticidal treatment may not be sufficient to cover the costs.

This does not mean that soybeans in all countries do not require insecticidal seed treatments.

What it really means is:Even when growing the same crop—soybeans—the optimal seed treatment strategy may vary by region.

Cotton: Early-season Insects and Seedling-Stage Diseases May Be Equally Important

Cotton may face certain seedling-stage diseases and insect pests, such as thrips, during its early growth stages.

In markets with clear dual risks, insecticide-fungicide combination formulations may be a product direction worth evaluating.

However, cotton seed treatment methods, surface conditions, and processing procedures differ from those of wheat and soybeans.

Therefore, whether a formulation is suitable for cotton must be confirmed through appropriate seed treatment processes and safety evaluations.

Why is field emergence still poor even after using seed treatment products?

This is a common issue encountered after seed treatment products are sold.

Customers may have purchased insecticides, fungicides, or combination products, but the following issues may still occur:

• Uneven emergence;
• Seed rot;
• Seedling death;
• Poor root development;
• Early insect damage;
• Missing plants in the field.

In such cases, the product cannot be immediately deemed substandard.This is because seed treatment only manages certain risks within its designed and registered scope; it does not resolve all germination issues.

Rapid Diagnosis of Germination Issues

Field Observations	Possible Issues	What to Check First
Seed Rot in Soil	Specific Pathogens, Waterlogging, or Seed Quality	Pathogen Identification, Seed Quality, and Soil Conditions
Damping-off after seedling emergence	Pathogen infection during the seedling stage	Target pathogens and fungicide coverage
Feeding damage on seeds or young roots	Soil-borne pests	Actual pest species and registered insecticides
Seedlings still damaged by aphids	Protection window, pest occurrence period, or susceptibility	Label information, pest outbreak timing, field monitoring
Missing plants in the field but no clear signs of pests or diseases	Seed viability, seeding, or environmental issues	Germination rate, seeding depth, soil conditions
Formulated products still fail to control a specific disease	Target pathogen is not within the spectrum of activity or other issues exist	Pathogen identification, active ingredient activity, and registration
Decreased germination rate after treatment	Dosage, seed quality, or treatment process	Control trials, treatment rate, and seed viability
Significant performance differences between batches	Variations in seeds, formulations, or treatment equipment	Batch records, COA, and treatment process

Why can’t efficacy be judged solely based on emergence rate?

Because emergence rate is only one aspect of the final performance and does not directly indicate at which stage the problem occurred.
For example:

A batch of seeds may inherently have a low germination rate; even when a seed treatment product of qualified quality is used, the desired emergence may not be achieved.

On the other hand, if the soil is severely compacted or the seeding depth is inappropriate, even a combination of insecticides and fungicides cannot fully overcome these limitations.

Therefore, to evaluate the effectiveness of seed treatment, it is best to consider the following factors together:

• Untreated control;
• Initial seed quality;
• Pest and disease incidence;
• Application rate;
• Uniformity of seed treatment;
• Soil and seeding conditions;
• Actual seedling emergence performance.

Only in this way can the product’s effectiveness be distinguished from other influencing factors.

How should importers select fungicides and insecticides for seed treatment?

For importers and distributors, deciding whether to sell fungicide seed treatments, insecticide seed treatments, or formulated seed treatments (FS) separately is not simply a matter of selecting from a product catalog.

It involves local agricultural needs, product registration, market prices, and long-term supply planning.

Step 1: First, understand what pests and diseases actually need to be controlled locally

It is recommended to clarify the following information:

• Target country
• Major crops
• Seed treatment channels
• Common seed-borne or soil-borne pathogens
• Major early-stage insects
• Active ingredients currently in use
• Local seed treatment practices
• Major customers’ seed treatment equipment

If this information is unclear, one should not immediately assume that a combination product will necessarily have a better market.

Step 2: Determine which functionality is missing from the current product line

Suppose a distributor already sells two fungicide FS products.

If there is little difference between the two in terms of target pests, registered crops, and price range, adding a third fungicide FS product may simply increase inventory.

Conversely, if the local market already has a well-established fungicide regimen but lacks specific tools for managing early-stage pests, introducing a corresponding insecticidal seed treatment may be more meaningful.

Similarly, if the market has long experienced concurrent outbreaks of diseases and pests, a well-registered, formulation-stable combination seed treatment may be more suitable for local seed processing companies.

A product line requires different functionalities, not an endless increase in product variants.

Step 3: Check FRAC and IRAC Groups

Fungicidal seed treatments should focus on the FRAC Group.

Insecticidal seed treatments should focus on the IRAC Group.

For example:

Active Ingredient	Classification	Primary Technical Role
Fludioxonil	FRAC Group 12	Specific seed-borne and seedling-stage fungal diseases
Metalaxyl-M	FRAC Group 4	Specific oomycete pathogens
Difenoconazole	FRAC Group 3	Specific fungal diseases within the scope of registration
Azoxystrobin	FRAC Group 11	Specific fungal diseases within the scope of registration
Thiamethoxam	IRAC Group 4A	Certain early-stage insects
Imidacloprid	IRAC Group 4A	Certain early-stage insects
Clothianidin	IRAC Group 4A	Certain early-stage insects

It is also important to note:

Thiamethoxam, Imidacloprid, and Clothianidin all belong to IRAC Group 4A.

Therefore, having three different active insecticidal ingredients does not mean there are three different modes of action.

Additionally, different countries may have varying restrictions on the registration and use of these active ingredients and treated seeds, which should be confirmed at the beginning of the project.

Step 4: Compare Formulations, Quality, and Seed Treatment Performance

FS is merely a formulation type and does not directly indicate product quality.

Even if two products have the same active ingredient and labeled concentration, the following should be compared:

• Measured concentration of the active ingredient;
• Relevant impurities;
• Suspension stability;
• Storage stability;
• Viscosity and flowability;
• Seed coverage and adhesion;
• Seed flowability;
• Compatibility with germination;
• Packaging compatibility;
• Batch consistency.

Some of these fall under formulation specification testing, while others pertain to the application evaluation of specific seeds and treatment processes.

It is not sufficient to assume that a product will perform consistently across all seed processing equipment solely based on the content meeting specifications on the COA.

Step 5: Confirm Registration and Long-Term Supply Conditions

Importers must also confirm:

• Source of the active ingredient;
• Source of the formulated product;
• Product specifications;
• Registration documentation;
• Batch traceability;
• Available technical documentation;
• Packaging requirements;
• Continuity of product supply.

Depending on the target country and project phase, the following may be required:

• COA
• SDS / MSDS
• TDS
• Product Quality Specifications
• Formulation Technical Information
• Stability Data
• Applicable Seed Treatment Evaluation Data
• Documents Related to Existing Registrations

Additionally, labels, transportation, usage restrictions, and food and feed isolation requirements for treated seeds should be reviewed.

SunAgro’s seed treatment product categories can be used to further compare the actual product specifications of single-component fungicides, single-component insecticides, and formulated suspensions (FS).

Frequently Asked Questions on Seed Treatment Fungicides and Insecticides

Can seed treatment fungicides control soil-borne pests?

No.

Seed treatment fungicides primarily target fungi or oomycetes within their registered scope and are not intended to replace insecticides for managing soil-dwelling insects.

If seeds or seedlings are damaged by soil-dwelling pests, identify the insect first, then evaluate insecticide products with corresponding registered uses.

Can seed treatment insecticides control seedling damping-off?

Insecticides should not be considered a substitute for seedling disease management.

Damping-off may be caused by Pythium, Rhizoctonia, or other pathogens.

The specific pathogen should be identified first, and then an appropriate fungicidal active ingredient should be selected.

Do all seeds require a combination of insecticide and fungicide?

No.

Whether to use a combination formulation depends on whether the target crop faces both manageable disease and early-stage pest risks simultaneously.

For markets with only a single risk, a suitable single-component product may be more cost-effective.

Does a combined insecticide-fungicide formulation always improve germination rates?

This cannot be guaranteed.

The primary function of seed treatment is to reduce losses caused by specific pests and diseases, not to restore the viability of low-vitality seeds.

If the seed quality is poor or sowing conditions are unsuitable, even the use of multi-ingredient combination products cannot guarantee an increase in germination rates.

Why do two fungicides need to be used in combination?

The main reason is likely that they target different pathogens or have different modes of action.

For example, Fludioxonil and Metalaxyl-M target different pathogens.

However, if the two ingredients do not effectively cover the target pathogen spectrum, adding a second ingredient may not be practical.

If fungicide seed treatment has already been applied, can insecticide seed treatment be added?

Whether this is possible depends on the registered label, treatment process, and compatibility.

For markets requiring simultaneous management of both diseases and pests, pre-formulated combination products or other treatment solutions that meet local registration and processing requirements can be evaluated.

It cannot be directly assumed that two independent products can be mixed or applied in combination at will.

Can seed treatments protect crops throughout the entire growing season?

Generally, no.

Most seed treatment products are primarily designed for the seed germination and early seedling establishment stages.

As the crop grows, it is still necessary to monitor for pests and diseases based on actual conditions and take necessary follow-up management measures.

Is it better to have more active ingredients in a FS formulation?

No.

What truly matters is whether each active ingredient has a clearly defined target risk, an appropriate application rate, good formulation compatibility, and legally approved uses.

More active ingredients may lead to more complex production, registration, and quality control requirements and do not necessarily result in higher commercial value.

How to Build a Seed Treatment Product Line Suitable for the Local Market?

A well-designed seed treatment product line should ensure that each product has a clear purpose, rather than simply packing as many active ingredients as possible into every product.

For distributors new to the market, you can start by establishing a simple decision-making framework:

Product Direction	Problems to Address	Key Pre-Purchase Considerations
Fungicide FS	Identified seed-borne and soil-borne disease risks	Pathogen spectrum, FRAC Group, crop registration
Insecticide FS	Identified early-stage insect risks	Pest species, IRAC Group, protection window
Insecticide + Fungicide FS	Both types of early-stage risks are equally important	Ingredient allocation, formulation quality, and economic value
Specialized seed treatment solutions	Markets with specific treatment or processing requirements	Seeds, equipment, treatment processes, and registration requirements

As the market evolves, products can be added based on different crops, pathogens, pests, and price ranges.

However, for every new SKU added, we should be able to answer:

Compared to existing products, what new problem does it actually solve?

If two products differ only in packaging, brand name, and formulation strength, yet target the same pests and diseases, the same application scenarios, and similar customers, then the second product may not truly add value to the product line.

Evaluate Seed Treatment Products with SunAgro

The question is not which is more important: fungicides or insecticides in seed treatment.

What truly needs to be answered is:

During the germination and seedling establishment stages, do local crops primarily face the risk of disease, insects, or both?

If the primary risk comes from pathogens, priority should be given to evaluating the corresponding fungicidal seed treatments.

If the primary risk comes from insects, it should be confirmed whether locally registered insecticidal treatments are suitable.

If both types of risks are indeed equally significant, then compound seed treatments (FS) with a clear division of roles among active ingredients can be further evaluated.

SunAgro serves pesticide importers, distributors, registration partners, and specialized seed treatment channels by providing seed treatment products with various active ingredients and formulations. We also support specific collaborative projects by providing product documentation, sample evaluations, and long-term supply coordination.

If you are selecting or planning to use seed treatment products, please provide us with the following information:

• Target countries and markets;
• Major crops and seed types;
• Common seed-borne or soil-borne diseases in the region;
• Major soil-dwelling or early-stage pests;
• Currently used seed treatment products;
• Desired active ingredients and formulations;
• Requirements for single-ingredient or formulated products;
• Registration status for target crops;
• Seed treatment equipment and packaging requirements;
• Estimated annual procurement volume.

Based on the actual pest and disease risks in your target market, we can assist in discussing suitable product specifications, formulations, technical documentation, and distribution partnership options.

A good seed treatment solution does not involve subjecting every seed to as much pesticide treatment as possible, but rather ensuring that each active ingredient serves a specific purpose and that the cost of each treatment corresponds to the actual risks that need to be managed.