Corn grain yields were significantly (P ≤ 0.05) increased by N fertilizer addition from 2003 to 2005. Sulfur addition also significantly increased the average yield of corn in 2002 and 2003. An N × S interaction for corn yield was observed in 2005. Sulfur application at 33 kg ha−1 significantly (P ≤ 0.05) increased corn yield at the intermediate N rate of 133 kg ha−1, and showed a general tendency to increase yield at lower N rates in 2004 and 2005. Nitrogen and S concentrations in corn grain were increased by application of 200 kg N ha−1, and S concentration was increased by S application in 2005. These results suggest that application of S fertilizer, with N, can promote the uptake of N by corn in S-responsive soils. This will decrease the amount of N required for high-yield corn production and reduce production costs and degradation of water quality associated with oversupply of N.

Download report here