Evaluation of Phosphonate Fungicides for Control of Pythium Blight on Creeping Bentgrass and Perennial Ryegrass

Phosphonate fungicides are used by golf course managers to control Pythium diseases, suppress anthracnose basal rot, alleviate summer stress, and improve turf quality. In many areas of the northeast, phosphonate products are applied at regular intervals throughout the summer as part of a fairway and putting green management program. Currently, over a dozen phosphonate fungicides and fertilizers are available on the golf turf market. Although these products have similar active ingredients and modes of action, they differ in trade name, formulation, label terminology, uses, and price. Understanding the different phosphonate products and how they perform in the field should help superintendents decide which product is most suitable for their particular need.