White mould is a fungus caused by Sclerotinia sclerotiorum, and tends to cause a bleached area of the stem, with black oblong sclerotia developing in the centre of the affected area, and inside the stem. But, we don’t want it to get that far. Enter fungicides.“The number one problem that growers have in timing fungicides is putting them on too late,” says Chris Gillard of the University of Guelph – Ridgetown Campus. “Every fungicide product that we have on the marketplace today are protectant products.”
That means you have to take proactive measures, spraying even before actually seeing the disease in the crop. To make that decision, Gillard encourages farmers to walk their soybean fields daily during flowering, looking at soil and canopy moisture conditions, forecasts, the history of the field and the susceptibility of the variety planted.
In this episode of the Soybean School, Chris Gillard talks about the economics and agronomics of making the time-sensitive decision to spray for white mould, and some of the points to consider for a successful application of fungicides.