8/9/2021 - By Dr. Paul Giordano

Phosphonate, or phosphite, products have long been known to contribute to direct and indirect control of important diseases like Pythium blight and Pythium root rot on turf. Now, Title Phyte® can get its proper due as an industry leading disease control solution, with the official registration of Title Phyte® Systemic Fungicide – Part of the Harrell’s ProtectMAX® line of products.

What’s changed?

While new claims can now be made around the fungicidal benefits of Title Phyte®, the product itself has not changed. It’s the same great formulation, same 0-0-30 analysis, and same load of potassium phosphite - which happens to be among the highest a.i. load of any phosphite product on the market. The only thing that has changed is the product label, which now includes disease control claims and instructions on how to use Title Phyte® as a fungicide. As seen below:

Why the new Label?

In order to make claims of disease control, a product must obtain a registration number from the United States Environmental Protection Agency (EPA). This involves a rigorous, and often expensive submission and review process – one that most companies are not willing to undertake with nutritional type products. Harrell’s is dedicated to providing our customers with the most robust, agronomically sound and economically efficient tools; and while Title Phyte® will continue to be known as an important nutritional supplement, which can be used to bolster overall plant health, it can now be reliably promoted and positioned as a true fungicide solution within our customers agronomic programs.

How does it work?

Phosphite fungicides are an important mode of action (FRAC Group P07) that work to suppress disease activity directly, by inhibiting phosphate metabolism in certain fungal and oomycete organisms. Phosphites have also been shown to indirectly assist in disease control by stimulating natural plant defenses or phytoalexins. Phosphites like Title Phyte® have symplastic ambiomobility – a fancy way of saying they can translocate in both the xylem (up) and the phloem (down) of the plant. Their systemicity and unique mode of action result in what’s likely a multi-site inhibition of pathogen growth and metabolism. This allows Title Phyte® to control diseases in a way that helps to mitigate fungicide resistance to traditional single site chemistries. Check out the below graph that shows just how effective Title Phyte® can be, when applied on regular intervals, to combat an aggressive disease like Pythium blight under high pressure.

For further reading, a more comprehensive review of phosphites as fungicides from Dr. Pete Landschoot at Penn State University can be found HERE.

Bottom Line

Title Phyte® is a perfect addition to any spray tank and a staple for added plant health assurance, nutritional benefits for potassium needs, and improved disease control throughout the growing season. Stay tuned for more exciting information as the Harrell’s R&D team continues to put Title Phyte® “head-to-head” up against other industry standards, in research trials around the country.