Nutrien Ag Solutions Seed Guide 2019 | Page 27

Disease management Blackleg, clubroot and sclerotinia continue to be a triple threat for Western Canadian canola crops. These devastating diseases can result in yield losses of up to 50%. Nutrien Ag Solutions has invested heavily in researching the best disease packages and developing new hybrids with genetics proven to combat current predominant blackleg strains, as well as high resistance to newly emerging and well-established clubroot pathotypes. Blackleg Blackleg resistance has been available in commercial canola varieties since the early 1990s. A shift towards increasingly virulent strains of the blackleg fungus has resulted in the breakdown of resistance in many traditional canola varieties. Increasing canola acreage and shortened rotations have contributed to this. Newer R-rated hybrids have been tested against current strains of the fungus and provide good protection against blackleg in the majority of locations. Nutrien Ag Solutions varieties are tested thoroughly across Western Canada and Proven Seed has a leading line-up of new R-rated varieties. PV 533 G has consistently demonstrated exceptional blackleg resistance effective against current prevalent strains of the fungus. The next generation of hybrids from Proven Seed, including new  PV 540 G, offer world-class protection with our continued evolution of blackleg resistance genetics. As the clubroot threat continues to evolve, canola varieties with multiple effective resistance genes are the first line of defense, offering additional protection and durability. Crop rotation is central to long-term disease management and will help preserve the resistance genetics currently available. Proven Seed introduced the first and only true multigenic canola variety with PV 580 GC. Now it’s time for the next evolution in clubroot defense, PV 585 GC, which boasts superior resistance to both clubroot and blackleg, along with strong yields. Intermediate rated hybrid PV 580 GC – Multigenic Sclerotinia DK 74-44 BL (L) vs PV 540 G (R) Clubroot Clubroot is a serious threat to both current and future canola production due to its high potential for adaptation, especially in regions of intense canola production and shortened rotations. Clubroot has many strains which can exist in the soil of an infested field. Since the disease was identified as problematic in canola in 2003, the predominant strain in fields has been P3. Resistance in most clubroot-resistant (CR) hybrids is becoming ineffective as multiple new strains are virulent on these hybrids, including the 5X strain. Sclerotinia stem rot is one of the most destructive diseases in western Canadian canola. The severity of sclerotinia is extremely variable from year to year, region-to-region and even from field to field. Sclerotinia has become more serious as canola production has increased, likely due to a combination of more acres of canola in rotations and management practices that contribute to high yields, but also produce dense canopies, which are a better microclimate for disease development. Foliar fungicides remain the main control strategy for sclerotinia. But seeding a variety with tolerance to sclerotinia also reduces your risk. PV 591 GCS from Nutrien Ag Solutions features the Pioneer Protector ® sclerotinia resistance trait. This trait provides several benefits to growers including a reduction in disease incidence, increased flexibility and insurance when timing fungicide applications, convenience as sclerotinia protection is planted with the seed, and control regardless of weather patterns throughout the entire growing season. Canola 25