Ducks Unlimited Canada: Winter wheat fertility program to maximize yield potential of new winter wheat varieties
Elmer Kaskiw, Ducks Unlimited Canada, Western Ag Lab and Professional Agronomy
To compare historical/standard “Producer Practice (100% spring)” fertility program to a balanced “High Yield Practice (Balanced)” as determined by Western Ag Soil analysis and recommendations.
Overall, results from the 2020/2021 growing season indicate that yields of some winter wheat varieties respond better to a balanced fertility program than others. Additionally, yield results from the Arborg site demonstrate a potential yield benefit of a balanced fertility program, as wheat grown under a balanced fertility program at this site yielded significantly higher than wheat grown under a current producer fertility program. Winter wheat protein content was demonstrated to likely be more influenced by winter wheat variety than fertility management practices in the 2020/2021 growing season, as fertility management practice only had significant impact on winter wheat protein content at the Roblin site, while variety significantly influenced protein content at all sites. Test weight of harvest grain was significantly greater in wheat grown under current producer fertility practices than in wheat grown under a balanced fertility practice at two sites indicating a potential test weight benefit of applying all nitrogen in spring. Continued field study is necessary to further evaluate the performance of new winter wheat varieties under both fertility management strategies, and to effectively develop fertilizer management recommendations that winter wheat producers can implement in their production systems.
Following decades of extensive work in winter wheat production in North America, many researchers
and producers have begun to implement best management practices to obtain higher grain yield and
improve profitability in the crop. Management practices presently being implemented to improve
winter wheat production include; increasing seeding rate, application of starter fertilizer by banding
during seeding, variety selection, pest control (Anderson, 2008) and split application, during planting in
fall and at tillering or stem elongation in spring (Schulz et al., 2015). Fertility management, in particular
nitrogen and phosphorus, remains an integral part of the overall management package aimed at
achieving higher yields in winter wheat (Halvorson et al. 1987). Recommended fertilizer management,
particularly nitrogen management, differs widely in winter wheat production, but the crop’s nitrogen
demand is correlated to yield potential and availability of moisture in dryland production systems (Beres
et al., 2018). Compared to spring wheat, winter wheat presents more challenges in development as a
result of its higher nitrogen demand during the long vegetative phase, hence the reason why it requires
25 to 50% more N than spring wheat in the Prairies (Fowler et al., 1989). The ideal fertility management
package would help counteract the escalating cost of winter wheat production per unit area, which is
the main goal that producers aim to achieve. There is still a knowledge gap on the rates and timing of
nitrogen fertilizer application, particularly in Western Canada, that result in improved yield without
compromising grain quality and economic returns. Morris et al. (2018) suggested the implementation of
adaptive use of nitrogen to help augment and improve nitrogen application rate decision making by
farmers. Therefore, there is a great need to continue with research on the best management practices
that can be availed to producers to improve economic returns in winter wheat production. Nitrogen is
most often the focus of crop fertility in field studies. However, having a balanced approach and
considering other essential nutrients, such as, phosphorus, potassium and sulphur and micronutrients
available in the soil, offers great yield potential when nitrogen needs of the crop are met. Perhaps more
efficient returns on investment potential can be achieved as fertility management is optimized.