2/13/2024 - By Dr. Paul Giordano

Microdochium patch is caused by the pathogen Microdochium nivale – the same fungal organism that causes pink snow mold on turfgrass. This disease can be very unsightly and exceptionally damaging when conditions are favorable for extended periods of development. It can occur on both cool and warm-season turfgrasses and poses significant issues in areas where cool, wet, rainy weather persists.

Harrell’s ProtectMAX® Title Phyte® Systemic Fungicide has been a staple product in many agronomic programs for years. Its quality formulation and well-documented disease control and nutritional benefits help to set it apart from other potassium phosphites. In 2021, Harrell’s went the extra step and registered Title Phyte® as a fungicide through EPA (Environmental Protection Agency) regulatory channels.

This allowed for more dedicated research and development efforts with Title Phyte® to explore different disease control benefits and added value potential of Title Phyte® to turfgrass managers. It’s through these efforts that Harrell's ProtectMAX® Title Phyte® Systemic Fungicide is now one of the only potassium phosphite fungicides labeled for the control of Microdochium patch.

Microdochium Patch Control

Microdochium patch is particularly challenging due to its prolific sporulation and ability to spread via mechanical traffic and mowing. The disease can damage the turfgrass foliage and work its way down to the crown – ultimately leaving circular patches of dead grass and voids in the stand. Cultural practices like reducing surface moisture and limiting nitrogen fertilization leading into the winter can help mitigate the disease, but fungicides are often needed for complete control. There are relatively limited fungicide options available for control of this disease as well as documented resistance issues in Microdochium patch to certain chemistries.

Using Phosphorus Acid for the Control of Microdochium Patch

Plenty of research has been done over the past 10 years that has explored alternative methods of controlling Microdochium patch on turfgrass. Phosphorus acid – the active fungicidal component in Title Phyte®- has shown in numerous studies to both directly and indirectly inhibit the growth and disease development of Microdochium nivale on turf.

This has given rise to different agronomic program recommendations that incorporate phosphorus acid and other non-traditional fungicidal chemistries to aid in the control of Microdochium patch in areas that have persistent or chronic disease epidemics throughout the season.

Title Phyte® Research and 2ee Label Recommendation

Trials have been conducted with Title Phyte® Systemic Fungicide that have proven excellent efficacy in controlling Microdochium patch alone or in combination with iron-based fertility products (such as Harrell'sMAX® IronMn Mg). The data and photos below are from an Oregon State University trial with Dr. Alec Kowalewski.

Under extremely high disease pressure, preventive applications of Title Phyte® showed nearly complete control of Microdochium patch at 4 fl oz/1,000 sq ft when applied at a 14-day interval. With a growing need for new options and improved disease control methods on Microdochium patch, it was an easy choice to pursue a label expansion for Title Phyte®. The new 2ee recommendation for Microdochium patch makes Title Phyte® one of the only potassium phosphite products on the market today labeled for the control of this disease.

How to Use Title Phyte® in Disease Control Programs

Title Phyte® should serve as the backbone of any disease control program on golf courses and other high value turf areas. Flexible use rates of 1-5 oz/1,000 sq ft allow for applications at varying intervals to greens, tees, or fairways. Whether used to help fight Pythium blight and anthracnose during hot, humid stretches of the growing season or for added Microdochium patch control through the cooler parts of the year, the systemic movement of Title Phyte® and supplemental potassium nutrition makes it a great tank addition in any situation.

Additionally, with no documented cases of resistance, Title Phyte can be incorporated as a rotational tool or in combination with other fungicides to help consistently bolster plant health and efficacy on key diseases.

For more information on Harrell's ProtectMAX® Title Phyte® Systemic Fungicide and other Harrell's research trials and innovations, reach out to your local Harrell's Representative.