GrainsWest Spring 2021

Winter 2021 grainswest.com 21 THE AGRONOMICS OF A RECORD CROP Watson has farmed on the east coast of New Zealand’s South Island for more than 50 years and has a reputation as a perfectionist. He set out to beat his own previous record with assistance from David Weith, regional sales manager with Bayer CropScience as well as input from additional crop advisors. For Watson, the challenge was to determine just how high his wheat yield could go. “The Guinness World Record is a nice recognition of our hard work and new innovations we’ve put in place,” saidWatson. “We were pleased with what we accomplished in the 2017 record result, but we also sawwhere we couldmake improvements and achieve an even higher yield.” At the start of the 10-month cropping season in April 2019, Watson sowed Kerrin, a feed wheat cultivar developed by KWS Seeds of Germany. He believes his use of all-liquid nitrogen and close monitoring of plant health helped achieve his 2020 results. “With our precision farming methods and using liquid nitrogen it helped to even out production over the paddock. We are pleased if we see yields increase year-on-year by 100 to 200 kilograms/ha [about four to seven bushels]. So, to beat my [2017] crop by almost 600 kg/ha [about nine bushels] exceeded even my hopes.” To produce his record crop, Watson’s ambitious agronomic program included pre-emergence and in-crop weed control and fungicide treatments and eight separate nitrogen applications. The crop also received about 40 pounds of phosphorus, 89 pounds of potassium and 78 pounds of sulphur as well as six applications of Yara micronutrient products that included magnesium, manganese, zinc, copper and boron. “The fixed costs are the same for a 15-tonne crop verses a 12-tonne crop,” said Weith, who has worked with Watson for many years. “On the Watson farm, all wheat fields are treated the same no matter the variety. The limiting factor is the soil type and field variability.” Weith said there is probably no simple secret to yield optimization. Rather, it’s about the alignment of agronomic and management practices. With good soil as a starting point, these include appropriate variety choice, fertilizer regime, disease and insect management as well as plant density. More difficult to control, this broad formula extends to adequate moisture and good harvest conditions. THE YIELD GAP IMPERATIVE Wheat, wherever it’s grown, has greater yield potential than is now being realized. And the increase in wheat yield on any farm isn’t merely about bragging rights. Brian Beres is an agronomy research scientist at the Agriculture and Agri-Food Canada (AAFC) Lethbridge Research and Development Centre. He believes gains will be made in wheat yield that will play a key role in feeding the world’s growing population over the next 30 years. With heads that hung like grapes at harvest time, this world record crop demonstrated the wheat yield gap can be can surmounted. No easy feat, New Zealander Eric Watson grew the 258.8 bu/ac irrigated crop pictured above and opposite with the generous use of liquid nitrogen and additional inputs.