CURVULARIA LEAF SPOT
Causal Agent:
Curvularia spp.
Susceptible Turfgrass:
Wintergrass, Kentucky Bluegrass, Bentgrass, Fescue, Couch
Symptoms:
- Individual leaves initially show yellow and green dapple patterns that extend downwards from the leaf tipInfected leaves turn brown, then grey as they shrivel and die.I
- rregular shaped patches of thinned turn appear, often coalescing to affect larger areas.
- Stolons and leaf sheaths may also rot.
Conditions Favouring Disease:
- Curvularia Leaf Spot occurs in areas that experience prolonged leaf wetness for severakl consecutive days.
- Curvularia spp. Occurs at temperatures, 25C to 35C.
- Soil compaction and excessive levels of nitrogen and thatch.
Management Tips:
- Maintain balanced fertility.Increase the height of cut.
- Avoid nitrogen applications in the spring when the disease is active.Avoid over watering.Improve the drainage of the turf.
- Reduce thatch accumulation
General Comments:
- Curvularia is mostly secondary disease after primary pathogens such as Spring Dead Spot and Helminthosporium, have infected turfgrass.
- Physiological changes in the turfgrass plant can increase susceptibility to Curvalaria when the light intensity is low or when the mowing height is lower than recommended for the specific situation.
- Sometimes called “Melting Out”
Distribution:
Found in Queensland, New South Wales, Victoria and South Australia.