Testing Soybean Yield Response to Sulfur at Planting and Foliar Fertilzers (YEAR 2)

Kentucky will collaborate with researchers from Wisconsin, Ohio, Indiana, Minnesota, North Carolina, Arkansas, Louisiana, Virginia and Georgia on a multi-state project to evaluate the response of soybean to sulfur fertilization. Sulfur members of this multi-state effort developed the following proposal, Shawn Conley at Wisconsin was the lead author on the original draft, and the text below should be extremely similar to proposals submitted to the other states. Sulfur is an essential nutrient for crop production, often ranked behind only nitrogen, phosphorus and potassium in importance. Increased sulfur removal from higher crop yields, combined with reduced inputs from atmospheric deposition and other sources have increased the prevalence of sulfur deficiencies in some regions of the United States. There is widespread concern about potential sulfur (S) deficiencies in corn and soybeans in the United States. Sulfur is relatively immobile within the plant, so symptoms usually appear in the new growth. Atmospheric deposition used to supply a considerable amount of plant available S (about 8-15 pounds per acre annually), but with the implementation of the Clean Air Act, this amount has significantly decreased.