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Glossary Terms

Active ingredient

An active ingredient (A.I. ) is the chemical compound within a solution that is responsible for an intended biological or chemical effect. In other words, an active ingredient is the component of a crop protection product formulation that acts upon a target organism, like an insect or fungal pathogen. For example, an active ingredient in a fungicide may block the ability of a fungal cell to respirate, essentially cutting off the cell’s energy supply and blocking fungal spore reproduction


Azoxystrobin is a broad-spectrum fungicide used for both preventive and curative control of a wide range of fungal diseases. Azoxystrobin features both systemic and translaminar properties and can be applied as a foliar spray or a soil treatment. As a FRAC Group 11 fungicide, azoxystrobin belongs to the methoxy-acrylate group within the strobilurin class of fungicides, otherwise known as Qol inhibitors. For more information on this class of chemistry, see Strobilurin


Broad-spectrum is a term used to describe products that are effective against a wide range of organisms. For example, a broad-spectrum insecticide will control not just one but an array of different insect species, while a broad-spectrum fungicide will act on a variety of different fungal pathogens. When faced with multiple pest threats, a broad-spectrum solution helps to deliver a well-rounded defense.

Carboxamide SDHI

Carboxamide refers to a chemistry subclass within the succinate dehydrogenase inhibitor (SDHI) group of fungicides. As a class of SDHI chemistries, carboxamides act on the succinate dehydrogenase enzyme within fungal cells to disrupt cell respiration, block energy production and inhibit fungal growth and development. While carboxamide chemistries representing the SDHI mode of action have existed since the 1960s, newer, more powerful carboxamide subgroups, such as the pyrazole carboxamides, have been developed, with the latest advancement being the introduction of molecules like ADEPIDYN® technology (pydiflumetofen) and SOLATENOL® technology (benzovindiflupyr). In the case of ADEPIDYN technology, the carboxamide chemistry is differentiated even further as a novel N-methoxy-(phenyl-ethyl)-pyrazole-carboxamide class, which helps ensures even more potency, persistence and efficacy on a broad spectrum of pathogens and diseases. For more information on SDHI chemistries, see SDHI (succinate dehydrogenase inhibitor).


A curative product or solution is designed to treat an existing condition or infection and prevent it from spreading. For example, curative measures can be taken when a plant has already been infected with a disease, and further disease progression must be stopped.


Cyproconazole is a broad-spectrum systemic fungicide in FRAC Group 3, belonging to the triazole class of fungicides. Classified as a sterol-inhibiting fungicide, otherwise known as a demethylation inhibiting (DMI) fungicide, cyproconazole halts fungal growth by halting the synthesis of a key component of fungal cell walls, disrupting cell integrity and ultimately leading to fungal cell death.

Deoxynivalenol (DON)

Also known as vomitoxin, deoxynivalenol (DON) is the most commonly occurring mycotoxin in grain crops like wheat, barley, oats and corn. Produced by two fungal pathogens, Fusarium graminearum and Fusarium culmorum, deoxynivalenol infects grain during periods of high humidity and moderate temperatures. The presence of DON in grains can lead to substantial economic losses and significant health risks for both animals and humans, and great care must be taken to prevent DON contamination both in the field and during storage


Difenoconazole is a broad-spectrum systemic fungicide used to control a wide range of fungal diseases as either a foliar or soil-applied solution. Difenoconazole belongs to FRAC Group 3 and the triazole class of fungicides, and it is classified as a sterol-inhibiting fungicide, also known as a demethylation inhibiting (DMI) fungicide. As a sterol inhibitor, difenoconazole disrupts fungal cell membrane function and effectively halts fungal cell growth and development.


Fludioxonil is a broad-spectrum contact fungicide in FRAC Group 12, belonging to the phenylpyrrole class of fungicides. Fludioxonil’s mode of action inhibits the transport of a protein kinase within fungal cells, which stops spore germination and further cell growth. Fludioxonil is used to treat a wide array of diseases like Fusarium, Rhizoctonia and Alternaria.

Modes of action

Also known as a mechanism of action, a mode of action is a specific biochemical interaction between a target organism and the chemistry working against it. A mode of action describes how a product’s chemistry binds to a molecular target, such as an enzyme or receptor, within a target organism. For example, SDHI fungicides act upon the succinate dehydrogenase (SDHI) complex within the mitochondrial respiratory chain of target pathogens, blocking cell respiration and effectively shutting down energy production in fungal cells.

Plant health

Plant health is an overarching term that refers to the overall wellbeing of plant crops, taking into account several factors including a plant’s ability to properly take up and use nutrients or water, defend against pests and disease or adapt to changing environmental conditions. Healthy plants are more resilient to both biotic and abiotic stressors, require fewer crop inputs and ultimately produce more yield.


A preventive product or solution is designed to prevent an undesirable event or effect from happening. In other words, preventive measures are taken to stop something before it occurs. For example, applying a fungicide before conditions are favorable for disease development would be considered a preventive treatment.


Propiconazole is a broad-spectrum systemic fungicide in FRAC Group 3, belonging to the triazole class of fungicides. Classified as a sterol-inhibiting fungicide, otherwise known as a demethylation inhibiting (DMI) fungicide, propiconazole halts fungal growth by halting the synthesis of a key component of fungal cell walls, disrupting cell integrity and ultimately leading to fungal cell death.


Rainfastness is the ability of a product to withstand rain and moisture, often referring to the amount of time it takes for a product to dry or absorb into plant tissue after application. If a product is rainfast or has excellent rainfastness, you can rest assured that it will not be washed off by rain and will remain adhered to the surface it was applied to. However, rainfastness varies from product to product, and it is imperative that users consult the product label for guidance on proper application timing and weather considerations to ensure rainfastness. In general, it’s a good rule of thumb to not apply a fungicide when rainfall is expected shortly afterwards, allowing ample time for products to dry or absorb into plant tissue. Please consult product labels for more detailed information.

Residual control

Residual control refers to the ability of a product to remain effective and continue working after the initial product application date. The length of a product’s residual control, or its residual strength, will vary depending on several factors, such as product formulation (liquid, dust, etc.), environmental conditions and the type of surface on which the product is applied. For example, a fungicide with excellent residual control will remain active for months and can help to control successive generations of pathogens.

SDHI (succinate dehydrogenase inhibitor)

An SDHI, or a succinate dehydrogenase inhibitor, is a class of fungicides that target the succinate dehydrogenase enzyme complex in fungal cells. Belonging to FRAC Group 7, SDHI fungicides work similarly to FRAC Group 11 fungicides, blocking cell respiration and halting the production of energy within fungal cells. SDHI chemistries stop fungal growth and development, leading to fungal cell death.


Strobilurins are a group of popular fungicide compounds first developed in 1996 and derived from naturally occurring fungal isolates. Now the most widely used fungicide group in the world, strobilurins are members of FRAC Group 11 and 11A. Known as quinol oxidation inhibitor (QoI) fungicides, strobilurins bind to fungal complexes and block electron transport within the pathogen, effectively stopping spore germination and halting fungal growth.

Test weight

Often used as a grain quality indicator, test weight is a measure of density (mass/volume) in several agricultural crops, most often represented in pounds per bushel. Test weights tend to decrease as grain quality deteriorates, so higher test weights normally indicate higher quality grain.


Thiabendazole is a systemic fungicide belonging to FRAC Group 1 and the benzimidazole class of fungicides. As a ß-tubulin inhibitor, thiabendazole disrupts fungal cell growth and division and can also impair cell uptake of glucose. This broad-spectrum fungicide is used to control a wide array of diseases in agricultural crops.