Manganese (Mn) has become a nutrient of interest in soybean production systems in the Midwest. This interest stems from reports from Purdue researchers of Mn uptake reductions caused by the glyphosate tolerant gene in soybean. Interest also has come from grain yield responses in Kansas.

Manganese is an essential nutrient for crop production. In cases where Mn is not available, a plant can not finish its life cycle without it. Mn is involved with photosynthesis and a cofactor in many plant reactions. Mn activates about 35 different enzymes in the plant and also is involved in nitrogen metabolism in the plant.