Dollar spot disease pressure is now increasing, as temperature and humidity rise resulting in prolonged periods of leaf wetness, warns technical expert Sean Loakes.

Speaking to course managers with ICL at the 72-hole championship Melbourne Club, on the Brocket Hall Estate in Hertfordshire this week, Syngenta technical manager Loakes highlighted that although overall dollar spot pressure has been relatively low so far this season with the dry spring, early symptoms are beginning to be seen in disease hot spots.

“Turf management actions now, with cultural controls and fungicide treatments, can reduce the risk and prevent damaging loss of grass cover or surface quality,” he advised.

He highlighted the danger of dollar spot is becoming more severe, since the pathogen appears to be developing at lower temperatures and with shorter periods of leaf wetness.

“Researchers who designed the original forecasting model now report the evolving pathogen appears to be developing with shorter periods of suitable leaf wetness and temperature,” he said. 

The effect would be a double whammy of more frequent conditions for the disease occurring, and the capability for the disease to go through its lifecycle faster.

 “For courses in high pressure situations that find they have been consistently hit earlier by dollar spot, it may be necessary to target treatments at a lower pressure threshold, for example,” he advocated.

“Be aware of localised risks on your course, as irrigation and microclimates will increase periods of leaf wetness that pushes up pressure – and can leave turf open to attack.”