Quest Reliant Systemic Fungicide
Reliant from Quest Products is the phosphite-based fungicide with the lowest salt index on the market. It contains no sodium, ammonium or aluminum co-products that can harm your plants or the environment. Highly systemic, Reliant quickly and fully translocates to all parts of the plant. This powerful foliar fungicide controls multiple diseases and is highly flexible to use, Reliant is a fit for most tree care operations.
Quest Reliant Fungicide Label (PDF)
Quest Reliant Fungicide SDS (PDF)
Quest Reliant Fungicide Datasheet (PDF)
Quest Reliant Fungicide Treating Phytophthora on Palm Trees (PDF)
Reliant Works in Three Ways:
- It’s a fungicide: Kills pathogens on contact, in the soil and on the plant
- It’s a nutrient: Potassium builds plant health
- It’s a stimulant: Increases the plant’s production of phytoalexin antibodies that stimulate the plant’s immune system against disease
- It’s Flexible
- A “Reduced Risk” pesticide, Reliant has a 4-hour re-entry interval (REI) and a zero-day pre-harvest interval
- It’s Tank-Mix Friendly
- Compatible with most pesticides, except certain copper products
- Offers Multiple Foliar Application Methods
- Apply Reliant via root drench, root dip, soil incorporation, chemigation (except in California) and by basal bark application
- Perfect for Disease Resistance Programs
- Reliant has a unique mode of action, which makes it an ideal fit within resistance management program.
Always read and follow all label directions.
Reliant contains 45.8% mono- and di-potassium salts of phosphorus acid. When applied, Reliant is rapidly absorbed across cell walls. It quickly translocates throughout the entire plant and kills pathogens on contact. Reliant also works as a protectant, making the plant resistant to further disease infection by thickening plant cellular walls to prevent mycelia penetration.



