The second weekly Prairie wind trajectory cereal rust risk report for 2024 is available for download now at the following link: May 14-20, 2024 report.
As of the week of May 14-20, 2024, the overall Prairie cereal rust risk assessment and need for in-crop scouting is as follows:
Pacific Northwest – There were relatively low numbers of reverse wind trajectories that passed over the PNW region and into the Prairies, while stripe rust development is continuing, although levels are generally low, especially in commercial winter wheat fields in the PNW. Prairie winter wheat crops are progressing into the tillering stage, while much of the spring wheat crop has just been seeded or will be seeded over the next two weeks. Overall, as of May 20, 2024 the risk of stripe rust appearance from the PNW is limited and scouting for this disease in the Prairie region is generally not urgent.
Kansas-Nebraska corridor – There were no reverse wind trajectories that passed over the KS/NE region and into the Prairies from May 14-20, 2024, while stripe and leaf rust development are continuing, albeit levels are generally low, especially in commercial winter wheat fields in this region. However, elevated stripe rust levels have been observed in central regions of Kansas. Prairie winter wheat crops are moving into the tillering stage, while much of the spring wheat crop has just been seeded or will be seeded over the next two weeks. Overall, as of May 20, 2024 the risk of stem, leaf, stripe, and crown rust appearance from the Kansas-Nebraska corridor is relatively low and scouting for these diseases in the Prairies is not urgent.
The early and widespread appearance of stripe rust in the PNW, TX/OK and KS/NE regions is still concerning. Over the next 2-4 weeks if favourable weather conditions (especially more rainfall) occur in these source US regions, further rust development could occur. This would result in more rust spores being available to be blown into the Prairie region, as well as more northerly rust development into the Dakotas and Minnesota/Wisconsin. Currently, Prairie winter wheat fields are most at risk, but fortunately most current winter wheat varieties have intermediate to high levels of resistance, although AC Radiant, CDC Buteo, AAC Elevate, Broadview, and CDC Falcon are rated as susceptible (https://www.seed.ab.ca/variety-data/cereals/; https://saskseed.ca/wp-content/uploads/2020/12/2024-Varieties-of-Grain-Crops.pdf; https://www.seedmb.ca/pdf-editions-and-separate-section-pdfs/). If you are growing a stripe rust susceptible variety, it will be important to keep an eye on your crops and follow further PCDMN cereal risk updates (https://prairiecropdisease.blogspot.com/).