Seed & Chemical
Stripe rust in four Alberta counties
By Top Crop Manager
Apr. 27. 2015 - Stripe rust on winter wheat has been reported in Alberta, in the counties of Cardston, Lethbridge, Lacombe and Warner.
"Additionally, there was a report of potential stripe rust in the Edmonton area and there is some evidence that stripe rust overwintered in Alberta again this year," says Mike Harding, plant pathologist with Alberta Agriculture and Rural Development (AARD) at Brooks. "Frequent scouting of winter wheat fields across the province is recommended."
For moderately resistant (MR) cultivars of CWRW such as AAC Gateway, AC Tempest, CDC Chase, Emerson and Moats, weekly scouting is recommended. All other cultivars are susceptible and scouting is recommended every three to fivedays in regions already reporting stripe rust symptoms.
A fungicide application may provide an economic return when approximately one plant per square metre has stripe rust symptoms, says Harding. "The ideal crop stage for fungicide application is at head emergence targeting the head, flag leaf and penultimate leaf. Susceptible varieties with symptoms on one or more plants per square metre will require a fungicide application. The MR varieties may not require a fungicide, but scouting is still necessary in case disease pressure overwhelms the resistance and becomes severe (severe symptoms would cover more than five per cent of the leaf area in the upper canopy leaves)."
For more information on stripe rust biology, diagnosis and control measures, see Stripe Rust 101: What Is It, Why Do We Have It, What Can Be Done About It.