Anthracnose
Colletotrichum cereale (formerly C. graminicola)
Anthracnose basal rot, caused by Colletotrichum cereale, shows as orange-to-yellow individual plants in a non-descript pattern, with black setae on the leaves and black infection mats at the crown.
Identification
Orange or yellowing of individual plants in a non-descript pattern; black hair-like setae on the leaves and black infection mats at the crown.
Symptoms
Symptoms of anthracnose include small, orange/yellow spots on leaves that may coalesce to form larger, tan/brown dead spots. The disease tends to follow water movement patterns.
Signs
Signs of anthracnose include the presence of setae (black, hair-like structures containing conidia), crescent-shaped conidia with an oil drop spot in the middle, infection cushions at the crown (which will appear black), hyphopodia, and runner hyphae.
Biology
Colletotrichum is a fungal pathogen that can exist in saprophytic and pathogenic forms. It feeds on dead turf in its saprophytic form but causes disease in its pathogenic form by infecting the foliage and crown of the turfgrass.
Epidemiology
Anthracnose is a common disease on ABG greens, occurring season-long from March to October with peak incidence in the summer. On CBG, it is typically found in hot and stressful times, primarily in the transition zone and southern regions.
Favorable Conditions
Most severe from May to October, and often seen in shaded areas or those with poor air circulation.
Cultural Management
Cultural control options for anthracnose include proper irrigation at 80% of evapotranspiration, topdressing on a programmatic approach to bury the crown, controlling seedheads to redirect energy back into the plant, and using plant growth regulators (PGRs) such as trinexapac-ethyl. Additionally, applying nitrogen at the shoulders of the season and spoon-feeding in the summer, rolling, raising the height of cut (HOC), and increasing mowing frequency can also help control the disease.
Further Reading
University extension resources — open in a new tab.
Related Reports
No published reports yet for this pest.
Reports will appear here as they are peer-reviewed and published.