South Africa Turf Disease Guide - Pythium Root Rot (Root Dysfunction)

Disease and Insect Control
Pythium Root Rot PRR in Turf

Causal Agent:

Pythium aphanidermatum, Pythium aristosporum, Pythium graminicola, Pythium vanterpooli, other Pythium species.

South Africa Turf Disease Guide - Pythium Root Rot

Susceptible Turfgrass:

Annual Bluegrass and Creeping Bentgrass most susceptible. Bermudagrass and Seashore Paspalum can also be affected.


Pythium Root Rot is common on highly maintained turf, such as golf course greens. Although symptoms of Pythium Root Rot are typically non-distinctive, this disease can appear as yellow, irregularly shaped patches. The affected turfgrass is thin, off-colour, and slow growing, while the root system is stunted with reduced volume and vigour. Foliar mycelium does not occur.

Conditions Favouring Disease:

Some Pythium species favour temperatures between 0°C and 10°C while others thrive in temperatures between 21°C and 32°C. Pythium Root Rot occurs in areas with high soil moisture, poor drainage, and low light. It also infects locations with low mowing height and excessive wear.

Integrated Turf Management Tips:

  1. Increase the height of cut
  2. Apply optimum amounts of nitrogen, phosphorous, and potash
  3. Reduce mowing frequency and use lightweight mowers
  4. Avoid over-watering
  5. Apply low amounts of nitrogen in the Spring when roots are forming • Minimise the amount of shade
  6. Improve the drainage of the turf
  7. Reduce soil compaction
  8. Apply penetrant fungicides on a preventive basis

Just tap the links below to read about other turf diseases. Or download the full free guide at the bottom.

  1. Anthracnose
  2. Brown Patch 
  3. Brown Ring Patch (Waitea Patch) 
  4. Dollar Spot 
  5. Fairy Ring 
  6. Superficial Fairy Ring 
  7. Grey Leaf Spot 
  8. Large Patch 
  9. Microdochium Patch 
  10. Powdery Mildew 
  11. Pythium Blight 
  12. Pythium Root Rot (Root Dysfunction) 
  13. Red Thread 
  14. Rhizoctonia Zeae (Rhizoctonia leaf and sheath spot) 
  15. Rusts: Crown, Leaf and Stem 
  16. Spring Dead Spot 
  17. Summer Patch 
  18. Take-all Patch  and
  19. Take-all Root Rot 

If you would like to have a complete copy with all the turf diseases, you can download it on the link below.

PDF icon
Download the full guide here (14.41 MB).