Jarrod Miller, Extension Specialist – Agronomy, jarrod@udel.edu;; Amy Shober, Extension Specialist – Nutrient Management and Environmental Quality ashober@udel.edu

As corn has reached V3-V5 across the state, we have started to observe visual symptoms of sulfur (S) deficiency. Like nitrogen (N), sulfur deficiency can cause plant tissue to appear light green or yellow in color. However, one can tell the difference between N and S deficiencies by where they occur on the plant. Nitrogen deficiencies start on the lower (older) leaves because N is mobile in the plant. In contrast, S deficiencies start on the new growth because S is not mobile in the plant. In fact, S deficiency can cause the whole plant to be lighter in color. Another symptom of S deficiency is the appearance of stripes (interveinal chlorosis), as seen in this photo. While these stripes may also indicate a micronutrient or magnesium deficiency, the most likely cause of this striping is a lack of S. We feel confident that S is likely the cause of this symptom, as we have observed similar conditions that is grown on sandy, low organic matter soils. Plus, we have confirmed S deficiency with tissue testing in past seasons. Continue reading