Proven Performance Trials 2017 | Page 4

The availability of disease resistance traits through leading genetic packages is an important tool in managing canola rotations for long term sustainability of the crop . Blackleg , sclerotinia and , more recently , clubroot have become high priority issues when selecting a canola hybrid .

Blackleg

Blackleg resistance has been available in commercial varieties since the early 1990s . However , in recent years , the virulence of the blackleg fungus has been shifting , resulting in the breakdown of resistance in many traditional canola varieties . Multigenic resistance , which is available in all canola varieties sold in Western Canada , is a combination of qualitative and quantitative genes and is the best and most durable form of blackleg resistance . CPS plant breeders are constantly testing and incorporating the most effective genes into Proven Seed canola hybrids .

Sclerotinia

The recent introduction of varieties with some physiological tolerance to sclerotinia is another management tool for growers . These varieties have demonstrated a significant ability to reduce sclerotinia severity in the field and protect yield in years with average disease pressure , although a fungicide application may still be warranted depending on the conditions .

Clubroot

Clubroot is quickly spreading across the Prairies . CPS is proud to offer clubroot-resistant canola varieties that carry genetics which result in a reduction of disease to less than 30 per cent of a fully susceptible variety . Resistance does not mean that the variety is immune to the disease and some galls may still be produced if the disease is present in the field . Single-gene resistant varieties , which are effective against the predominant strains , can be grown in areas with low levels or no clubroot to keep spore levels low . These varieties should not be grown repeatedly in a short rotation as it increases the speed of which a shift towards a more virulent strain will occur . Two-gene resistant varieties , which have more than one resistance gene , offer additional protection , reduce selection pressure and enable resistance to remain durable for longer . These varieties are an excellent tool to rotate genetics where current clubroot hybrids are still effective but the risk of becoming susceptible is still high .

LPC Summary

• Hybrids with lower standability ratings are typically easier and faster to swath . This can lead to time savings in the field , and the ability to manage acres more effectively and efficiently .

• Yield potential can be maximized by selecting the right hybrids for the farm based on genetic potential , standability , days to flower and maturity .

• Environmental factors cannot be controlled , only managed . Seeding a variety of high-yielding hybrids increases the likelihood of attaining optimum returns . Disease resistance and tolerance is one tool in a sound canola disease management system ; rotations and field hygiene best practices are others .

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