Canadian canola challenging wheat
GroundCover™ Issue: 116 | Author: Rebecca Jennings
Canadian researcher Dr Malcolm Morrison gave an insight into the ‘home of canola’ at the GRDC Grains Research Update in Adelaide in February
A short growing window is no barrier to canola growers on the Canadian prairies, where the crop is gaining ground on wheat.
Australian grain growers and their advisers gained an insight into the home of canola at the GRDC Grains Research Update series, where Canadian researcher Dr Malcolm Morrison took the stage.
Australia’s frost events might pale in comparison to Canada’s minus 40°C temperatures, but Dr Morrison said there are similarities between the two nations’ canola farming systems, such as adjusting management in response to new varieties.
“Canada’s fathers of canola are your uncles of canola,” is how Dr Morrison put it. “Our problems are your problems too.”
Dr Morrison said that in the Canadian prairie provinces of Saskatchewan, Alberta and Manitoba, where most of Canada’s canola is grown, wheat dominates, with about 10 million hectares sown in 2014; however, canola is catching up, with more than eight million hectares planted.
Growing days – rather than rainfall – determine farming zones. Growers in the short-season zone of the northern prairies have just 90 to 95 days between planting and harvest. This period in the mid-season zone is 96 to 104 days, and 104 to 112 days in the long-season region to the south.
“We have to cram the crop in between the last spring frost and the first fall [autumn] frost,” Dr Morrison said. “By 30 days after seeding, we have the full canopy, 35 days after seeding the crop is about to bolt, by 50 days there is 10 per cent of bloom left and pods are developing.”
Price has driven the increase in canola planted and prairie canola yields have increased by 65 per cent from 1986 to 2013. Most of this occurred following the entrance of hybrid varieties with herbicide tolerance (HY/HT) into the market in 1999. Today, 95 per cent of canola varieties sown in Canada are HY/HT.
From 2000 to 2013, Canadian canola yields increased by 695 kilograms/ha, largely due to new varieties, but environmental factors also played a role.
Dr Morrison said precipitation in April and May increased by four millimetres per year from 2000 to 2013, with a corresponding yield increase of 4kg/mm. Atmospheric carbon dioxide (CO2), used by plants in photosynthesis, also increased by 25 parts per million since 2000.
Experiments have found that canola yields increase by about 1.7kg/ha per ppm of CO2, so 3kg/ha/year of yield increase can be attributed to this environmental factor.
Dr Morrison said management has had a lesser impact on yields since 2000 because many of the best management practices, such as no-till, seed treatments, planting, fertilising and harvesting methods, were already in place before then.
He said a challenge for growers is to keep pace with varieties: “New HY/HT varieties may need new management practices to achieve their full yield potential. Experiments have shown that these varieties will respond to higher nitrogen fertiliser, but may not necessarily be more nitrogen use efficient.”
Maintaining seeding rates is also critical to ensure establishment of these new varieties, as even with a high seed-germination rate, only 50 to 60 per cent of plants emerge.
Dr Morrison said the message being given to Canadian growers is to embrace variable-rate technology to optimise inputs, target a seeding rate of about 150 seeds per square metre (to achieve a plant population of 80 plants/m2), and aim for slower, shallower seed placement to improve emergence.
Looking ahead, Dr Morrison sees high-oleic soybean oils, which will come into production in the next five years, as the main threat to canola’s market share.
More information:Dr Malcolm Morrison,
Region National, Overseas, South