With the season in full flight, cocksfoot growers will be monitoring their crops for downy mildew and considering control options.
FAR’s Weather Platform is trialing a downy mildew prediction model (pictured here), based on parameters used in horticulture for onion downy mildew. For onion downy mildew, optimum sporulation conditions are the red flag, specifically consecutive days of it is critical. After that, looking at germination risk and the overall pattern of high pressure (spores and germ) and low pressure can help make decisions on the need for control.
Back to Cocksfoot downy mildew, FAR’s downy mildew prediction model is currently suggesting that this season has had less optimum sporulation periods than last year and that disease pressure may currently be lower (pictured here).
Last years’ experience was that good control and large seed yield increases were achieved when spraying started in mid- to late November. As fungicide applications made now will severely restrict control options later in the season when we know control can be effectively achieved, consider the number of downy mildew-specific applications you might need to manage the seasonal disease pressure in your area whilst maintaining an anti-resistance strategy.
Picture. A comparison of downy mildew sporulation and germination conditions this season and last suggests far fewer risk periods have occurred this season and that disease pressure may be lower (data collected using Methven weather station on the FAR weather platform, www.far.org.nz).