Battling white mould on soybeans

Jun 24, 2015

Tips to give farmers an edge

Farmers are always having to fight their way to success, whether it be by adhering to government regulations, dealing with the unpredictability of the weather, or warding off pests and diseases from their crops.

White mould has been a problem for farmers, but for soybean producers in Eastern Ontario, it’s been much more than that.

“Last year was probably the worst year in the last 10 for soybeans,” said Chris Gillard, Dry Bean Agronomy & Pest Management Assistant Professor at the University of Guelph’s Ridgetown Campus.

Gillard has come up with a checklist of things every grower should consider so they can have a better understanding of white mould and the dangers it can pose to their fields.

White mould

1.Size of the canopy
A full canopy will put your crop at risk of developing white mould.

2.Field’s moisture level
White mould can develop and start to spread when there’s a wet plant canopy for at least 72 hours.

3.Is the crop flowering?
Once the bean crop starts to flower, the risk of infection increases as the flowers provide a food source for the disease to grow and attack the soybeans.

4.Field history
A field that’s had white mould in recent years is still infected. Crop rotation is recommended, but it won’t eradicate the disease completely.

5.Yield potential and potential value
White mould is a disease of high-yielding crops with large canopies. If a high potential value is possible, fungicide application may be necessary

6.Weather forecast
Sunny skies and hot temperatures will reduce the crop’s potential for infection. Up to 28°C is ideal.

How does white mould work?

“Spores have been released inside the crop canopy and they’re not visible to the human eye,” said Gillard. “The spores land on the plant, then flower pedals from the plant often land on a branch and given the right weather conditions, will provide nutrients for the spores to germinate and start to grow.”

Gillard said there is a way to identify white mould on soybeans with the naked eye.

“Picture a funnel that’s about only 3-4mm across,” he said. “It sends that up the surface of the soil, the funnel opens up and the spores are inside that funnel. The wind takes them and blows them around. There are other fungi that do the same thing, so it takes some experience.”

Have you ever had to battle white mould? What measures did you take to do so?

Video: Evolution of Beef Cattle Farming

The Clear Conversations podcast took to the road for a special episode recorded in Nashville during CattleCon, bringing listeners straight into the heart of the cattle industry. Host Tracy Sellers welcomed rancher Steve Wooten of Beatty Canyon Ranch in Colorado for a wide-ranging discussion that blended family history and sustainability, particularly as it relates to the future of beef production.

Sustainability emerged as a central theme of the conversation, a word that Wooten acknowledges can mean very different things depending on who you ask. For him, sustainability starts with the soil. Healthy soil produces healthy grass, which supports efficient cattle capable of producing year after year with minimal external inputs. It’s an approach that equally considers vegetation, animal efficiency, and long-term profitability.

That philosophy aligned naturally with Wooten’s involvement in the U.S. Roundtable for Sustainable Beef, where he served as a representative for the Colorado Cattlemen’s Association. The roundtable brings together the entire beef supply chain—from producers to retailers—along with universities, NGOs, and allied industries. Its goal is not regulation, Wooten emphasized, but collaboration, shared learning, and continuous improvement.