Managing Sulfur for Spring Wheat in the Red River Valley
Alan Blaylock, Ph.D.
Dr. Alan Blaylock brings extensive North American and international experience in nutrient management to the agronomy team. University studies and service as a university extension soils specialist prepared him for a long career in the fertilizer industry. Having managed both domestic and global research and education programs, Dr. Blaylock has a wealth of experience in applying science-based nutrient management principles and products to solving practical questions. Dr. Blaylock earned Bachelor of Science and Master of Science degrees in agronomy and horticulture from Brigham Young University and a Ph.D. in soil science from Iowa State University. He has been in agriculture his entire life — from his childhood on an irrigated farm in eastern Oregon to teaching soil science at Iowa State University to his current role as an agronomist at Nutrien. These diverse experiences helped Dr. Blaylock develop the skills to excel in translating complex scientific principles into practical solutions. Although early in his university studies he explored computer science as a profession, deep family roots in agriculture brought him back to the people and values of his heritage. His career satisfaction comes from helping others improve the performance of nutrients and cropping systems.
Sulfur is increasingly deficient in many crops across much of North America. Reduced atmospheric deposition from cleaner factory emissions coupled with greater crop yields is credited with increasing deficiencies and greater need for sulfur fertilizers. Soil organic matter mineralization, atmospheric deposition, and irrigation water are usually the most important sources of non-fertilizer sulfur.
In wheat, sulfur is important for grain quality, being a key component of amino acids (cysteine and methionine) and important for dough elasticity of bread-baking flours. Increasing occurrence of sulfur deficiencies has prompted recent research to identify appropriate sulfur best management practices.
Recently published Minnesota studies examined sulfur sources, timing, and rates across soils of varying organic matter content. In one study, multiple sulfur sources were applied at different rates in spring before planting or in-season. In another study, sulfur response of six popular varieties to different sulfur rates was examined to determine if spring wheat varieties varied in the amount of sulfur needed.
Important findings of the study:
- Sulfur sources produced similar crop response.
- Sulfur response was greatest and most consistent in soils with less than 2 percent organic matter. Wheat grown in soils with greater soil organic matter often did not respond to fertilizer sulfur.
- Wheat varieties responded similarly to sulfur, and sulfur rates need not be adjusted for different varieties.
- Seven pounds of sulfur per acre was enough to maximize spring wheat yields and protein in Minnesota.
- Total tissue sulfur content was a better predictor of sulfur response than nitrogen to sulfur concentration ratio.
Do Hard Red Spring Wheat Varieties Vary in Their Response to Sulfur? 2019. D. E. Kaiser, A. K. Sutradhar, and J. J. Wiersma. Agron. J.
Find more information in the following research reports:
- 2016 Variation in Response to N and S Among Spring Wheat Genotypes Grown on Irrigated and Non-irrigated Soils
- 2015 Variation in Response to N and S Among Spring Wheat Genotypes Grown on Irrigated and Non-irrigated Soils
- 2014 Variation in Response to Sulfur Among Spring Wheat Genotypes
You may also find Sulfur for Minnesota Soils helpful in better understanding sulfur in soils and sulfur fertilizer management.