49 www.seed.ab.ca | fall.2018 Westlock, AB Greg & Clifford Cyre Cell (780) 307-4332 [email protected] Wheat AAC Brandon AAC Penhold AAC Crossfield - NEW AC Foremost Peas Cooper (Green) Faba Beans Snowbird The entire process is a matter of crossbreeding canola with resistant relatives through normal pollination procedures and recovering offspring that are clubroot-resistant. “Those offspring then have to be crossed with canola again and again through many generations, selecting the resistant offspring at each generation for use in the next cycle to obtain plants that maintain resistance, but have recovered the characteristics of high- performing canola,” Christianson explains. Weidler adds that unwanted genetic material from the resistance donor that negatively impacts the agronomic performance of the offspring is removed through several crossings of the offspring with elite parent stock. “Using molecular breeding tools, we can check the progress towards the end goal,” he notes. “Ideally, only the genetic sequence conferring clubroot resistance has been transferred and no other parts of the donor genome remain in the offspring.” Breeding Progress DowDupont was the first company in Canada to market clubroot resistant hybrids in 2009 (45H29). “Our hybrids have multi-source and multi-race resistance to clubroot, and have a high level of resistance to the most prevalent clubroot race – race 3 – along with resistance to races 2, 5, 6 and 8,” Falak notes. Pioneer has new canola hybrids that contains a new source of clubroot resistance that confers resistance to both the initial type and new pathotypes, and can be rotated with the original resistant hybrids.” For its part, Bayer CropScience has “identified several new potential resistance sources,” says Weidler, “and we have been able to demonstrate that these are different from what is currently on the market.” Christianson says that as Monsanto nears “actual commercial entry into the marketplace, we will have more to share about how second-generation resistance fits in with existing resistance traits to provide a sound disease management strategy.” No matter what resistant canola varieties are marketed, no company can predict how long a new variety will last before it’s compromised. This depends on too many factors, explains Weidler, including the resistance gene, environmental conditions and management practices. All the companies strongly agree that the existence of varieties with resistance is only part of the clubroot solution. Weidler emphasizes the importance of an integrated disease management approach for clubroot, and fully supports the recommendations of the Canola Council of Canada. Falak and Christianson echo the sentiment. “All resistance traits will be effective for longer periods of time if they are used judiciously,” says Christianson. “Choosing resistant seed is only one part of a successful disease management strategy. Growers need to include crop rotation, field scouting and early detection of clubroot, and minimizing soil movement between fields on equipment.” Falak agrees. He says following a proper canola rotation as well as rotation of resistance genes, combined with preventing soil movement and other agronomic measures “would enable sustainable clubroot management that would prolong efficacy of any new resistance sources that are introduced.” Treena Hein Dr. Marcus Weidler