How Drought Affects Corn

Every year corn producers somewhere struggle with drought conditions. The extent of corn yield loss is determined by stage of growth when drought hits as well as the hybrid's ability to withstand drought stress.

Leaves rolling at midday in corn field

Water Needs and Drought Effects

Estimated corn evapotranspiration and yield loss per stress day during various stages of growth

Estimated corn evapotranspiration and yield loss per stress day during various stages of growth

Derived from Rhoads and Bennett (1990) and Shaw (1988). From: What Happens Within The Corn Plant When Drought Occurs?, Joe Lauer, University of Wisconsin-Extension, 8/20/03.

Effect of Irigation Treatment on Water-Stressed Corn Yield

*Yield expressed as percentage of well-watered treatment. Adapted from Cakir, 2004.

Common Drought-Induced Nutrient Deficiency Symptoms

Potassium efficiency symptoms of corn

Potassium Deficiency. Yellow with necrosis on outer leaf margins.

Nitrogen deficiency symptoms of corn.

Nitrogen Deficiency. Yellow with necrosis up the midrib and lower leaves.

Nitrogen Deficiency. Yellow with necrosis up the midrib and lower leaves.

Nutrients enter plant roots by:
2. Diffusion
3. Root interception

  • Without water roots may not grow well and nutrient movement in the soil is limited.
  • Nutrient remobilization in the plant will occur when corn can't access nutrients in the soil due to poor root growth or lack of soil moisture.