Most turf grass diseases in the Midwest are caused by which organism?

• A. Bacteria
• B. Fungi
• C. Viruses
• D. Nematodes

Answer: (B)

Fungi are the main culprits behind most turfgrass diseases in the Midwest because the region’s warm, humid summers create long periods of leaf wetness that let fungal spores germinate and infect grass tissues. Fungi spread easily through wind-blown spores and water splash, thriving in thatch and moist turf to cause common problems such as dollar spot, brown patch, and powdery mildew. Bacteria and viruses can infect grasses, but they are far less common as the primary disease-causing agents in turf, and nematodes mainly affect roots rather than leaf or crown tissues. So, when turf disease pressure is seen in this region, fungal pathogens are the predominant cause.