Ohio grain crop response to sulfur fertilization

Abstract

Continuous declines in atmospheric sulfur (S) deposition along with increased S removal rates with crop harvest has the potential to lead to S deficiency in Ohio field crops. As a result, S fertilization has become more common over the past decade. However, the extent of S deficiency is unknown, as inherent soil properties and management practices influence S availability and uptake. We conducted 96 replicated trials, from 2013 to 2021 to (1) examine the response of corn (Zea mays L.), soybean [Glycine max (L.) Merr], and wheat (Triticum aestivum L.) to S application on a wide range of Ohio soils and differing management practices and (2) determine the ability of Mehlich-3 extractable S in soil, leaf S, and grain S concentrations to predict grain yield response to S fertilizer. Our results showed limited grain yield increases to S fertilization with an overall response rate of 7.3% (4 of 50 corn trials, 3 of 34 soybean trials, and 0 of 12 wheat trials). Sulfur fertilization increased leaf and grain S concentrations by 19.4% and 12% in corn, by 22.2% and 7.7% in soybean, and by 41.7% and 0% in wheat, respectively. These increases in leaf or grain S concentrations were not directly related to yield responses. Diagnostic tools of Mehlich-3 soil S, leaf S, and grain S concentrations failed to predict yield response to S. We conclude that S deficiency is not widespread in Ohio soils and that optimizing grain crop production does not currently require S fertilization.