Economic evaluation of seeding decisions in hybrid and open-pollinated herbicide-resistant canola (Brassica napus)

Herbicide-resistant canola (Brassica napus) is widely cultivated in western Canada. Data from a multi-year field experiment conducted at three locations in Alberta were used to investigate the effect of canola cultivar, time of seeding, polymer seed coating (PSC) on profitability and the net return risk. Cultivars included hybrid and open pollinated. Time of seeding was early and late fall, and early and normal spring. The hybrid canola generally had higher mean net return than the open-pollinated cultivar. The probability of thin canola stand was higher for fall dormant seeding compared with spring seeding. The use of PSC for early fall dormant seeding reduced the likelihood of thin canola stand, which translated into risk-efficient decision. However, PSC use for late fall seeding had mixed results. Early and normal spring seeding was generally risk-efficient at all locations. In exceptional cases, net returns from late fall dormant seeding (with or without PSC) were similar to that of spring seeding. Re-seeding of fall seeded canola in the spring could be beneficial, if the plant density was below 20 plant m-2. Seeding decisions were robust across a wide range of canola prices, based on the probability of negative net returns. Key words: Canola, fall seeding, net returns, polymer seed coat, re-seeding, risk