Downy Mildew

From Turf Wiki

• Pathogen: Sclerophthora macrospora

• Common Names: Downy Mildew, Yellow Tuft

• Climatic Zone: Temperate, Subtropical, and Tropical

• Geographic Distribution: North America, Europe, East Asia, Australia, Africa, South America

• Favorable Conditions: Generally conditions that promote good grass growth, as well as heavy water

• Hosts:Creeping Bentgrass, colonial bentgrass, velvet bentgrass, Perennial Ryegrass, Annual Bluegrass (Poa annua), bermudagrass (Cynodon dactylon), Tall Fescue, Kentucky Bluegrass, St. Augustinegrass, zoysiagrass, fine fescues

• Symptoms: Slightly stunted growth with a broadening of the blades, when severe yellow patches 1/4"-4" (1-10 cm) diamter. If conditions become cool and wet there may be a white, downy growth