Effect of N, P, and K on the Percent and Yield of Oil in Corn1

Abstract Fertilizer N, P, and K increased percent oil in corn (Zea mays L.) grain relatively less than they increased grain yield. The relative increase in percent oil was 8, 3, and 2% for N, P, and K, respectively. Oil yield was increased an average of 43, 54, and 11% by the addition of N, P, and K, respectively. The increase in yield of oil per unit land area was due more to increased grain yield than to increased percent oil in the grain.