Causal organism:
Pythium Spp
| Problem |
Pythium Foliar Blight / Grease Spot |
| Host Grass Types |
All turfgrass species |
| Symptons |
Small, discoloured spots that can enlarge very quickly to irregular areas of dead turf. May also show as ‘frog-eyes’. Grass becomes dark and watersoaked, feeling greasy to touch. Patches are shrivelled and matted when dry. Mycelia may be present during high humidity. The infection can look streaked as it follows channels of natural drainage and paths of mowing equipment |
Conditions that can favour the development of the disease
- Common in hot summer weather (29 - 35°C) with little air movement and high relative humidity
- Can occur at lower temperatures (20°C) when other environmental factors are conducive
- Poor drainage and waterlogging
- Lush, over-fertilized turf
- The disease spreads rapidly by mycelial growth, in water and on mechanical equipment, especially mowing infected turf on dewy mornings
Management strategy to reduce the likelihood of attack
- Optimise drainage and soil profile management to avoid waterlogging
- Use irrigation appropriately to avoid excess soil moisture
- Regular aeration to develop good soil structure for drainage and root development
- Topdress to improve the soil’s structure and drainage capabilities
- Avoid excessive nutrition
- Reduce thatch
- Use fungicides as part of your iTurf programme and be aware of causing resistance to one chemical group by its regular use
Pythium Foliar Blight / Grease Spot
