Grainswest - Winter 2024

Winter 2024 grainswest.com 41 “Any little contamination of infected seed can ruin a big shipment of grain.” — Reem Aboukhaddour “Outside, you see the plant as normal, but when the head forms, you start to see some sign of the infected grain. It’s not easy to tell infected plants from non-infected ones. The fungus will form a lot of spores and hijack all the grain.” As the crop emerges from the boot, farmers can observe a bluish-greyish spike, rather than a healthy light green. Crushed heads appear black, and that is the bunt ball inside the infected head. “Usually they make the tiller shorter, and the awns are more outward than inward,” added Aboukhaddour. “There are some clues, but it’s not easy to determine without training.” Often confused with loose smut, Aboukhaddour said bunt is hard to identify without training. She and her team conduct genetic testing for western Canadian breeders from government agencies, universities and the private sector. Bunt has been found across Canada and the U.S., but the Pacific Northwest and the Canadian Prairie are hot spots for infection. This is attributed to the higher elevation, high snow accumulation and cool spring. In Lethbridge, Aboukhaddour and her team regularly test genetic material for western Canadian breeders from government agencies, universities and the private sector. Thousands of spring and winter wheat lines are tested annually, each over the course of three years. A line receives a rating to match its worst performance, with environmental factors being considered. A farmer who suspects a crop may have bunt should scout in the early morning or afternoon—never during the middle of the day—as it is not easy to spot the difference between healthy and infected heads. Aboukhaddour noted people regularly confuse loose smut and bunt. This is because they are closely related diseases that originate from the same group of fungi and form black spores. In loose smut, however, spores are not contained under the intact glumes. Unlike rust, bunt does not travel on the wind, which is a huge plus for farmers. When infection occurs, it’s localized