Abstract
Ultra-early seeding of spring wheat (Triticum aestivum L.) on the northern Great Plains can increase grain yield and grain yield stability compared to current spring wheat planting systems. Field trials were conducted in western Canada from 2015 to 2018 to evaluate the impact of optimal agronomic management on grain yield, quality, and stability in ultra-early wheat seeding systems. Four planting times initiated by soil temperature triggers were evaluated. The earliest planting was triggered when soils reached 0–2.5 °C at a 5 cm depth, with the subsequent three plantings completed at 2.5 °C intervals up to soil temperatures of 10 °C. Two spring wheat lines were seeded at each planting date at two seeding depths (2.5 and 5 cm), and two seeding rates (200 and 400 seeds m−2). The greatest grain yield and stability occurred from combinations of the earliest seeding dates, high seeding rate, and shallow seeding depth; wheat line did not influence grain yield. Grain protein content was greater at later seeding dates; however, the greater grain yield at earlier seeding dates resulted in more protein production per unit area. Despite extreme ambient air temperatures below 0 °C after planting, plant survival was not reduced at the earliest seeding dates. Planting wheat as soon as feasible after soil temperatures reach 0 °C, and prior to soils reaching 7.5–10 °C, at an optimal seeding rate and shallow seeding depth increased grain yield and stability compared to current seeding practices. Adopting ultra-early wheat seeding systems on the northern Great Plains will lead to additional grain yield benefits as climate change continues to increase annual average growing season temperatures.
Highlights
Canada is a key global producer of high-quality spring wheat (Triticum aestivum L.), and in 2018 was the world’s third largest exporter (19.7 MT) and sixth largest producer (31.8 MT) of wheat [1]
Ultra-early wheat seeding systems based on soil temperature triggers as described in Collier et al [8] can produce greater grain yield by capturing the benefits of longer frost-free periods: early season growing degree-day accumulation, increased vegetative growth periods, early season precipitation, increased day-length at anthesis and reduced average temperatures at grain fill
Wheat grain yield and growing system stability can be increased by moving wheat planting earlier in the year on the northern Great Plains
Summary
Canada is a key global producer of high-quality spring wheat (Triticum aestivum L.), and in 2018 was the world’s third largest exporter (19.7 MT) and sixth largest producer (31.8 MT) of wheat [1]. A short frost-free period is commonly referenced as a grain yield-limiting factor on the northern Great Plains; increases in the average frost-free period from 1961 to 2018 are rarely referenced as contributing to wheat grain yield increase [4,5,6,7]. Ultra-early wheat seeding systems based on soil temperature triggers as described in Collier et al [8] can produce greater grain yield by capturing the benefits of longer frost-free periods: early season growing degree-day accumulation, increased vegetative growth periods, early season precipitation, increased day-length at anthesis and reduced average temperatures at grain fill. Iqbal et al [9] reported one of the primary limiting factors of wheat grain yield on the northern Great Plains was the short frost-free period that limits the length of the growing season. Lanning et al [10] investigated the yield of “Thatcher” wheat from six locations in Montana, USA, over 56 seasons and reported a grain yield increase of
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Free) 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
