Keep Your Eyes Open for Stalk Rots

Anthracnose on corn stalk rot ( Darrell Smith )

The stalk is your singular hope that the corn crop will stay standing. If disease infects your corn stalks, put the pedal to the metal to get that field harvested before it falls. And it’s not just wet seasons that product stalk rot, dry weather can create them, too.

Here are some common stalk rots, conditions that favor their development and solutions to try to mitigate this risk next year:

  • Charcoal Rot
    • Small black, round sclerotia inside the stalk that look like charcoal dust
    • Infects plants under drought stress conditions and more likely when soil temps are above 90°F and soil is dry
    • Irrigating or planting earlier, planting hybrids with resistance or later to avoid dry periods can help mitigate this disease
  • Gibberella Stalk Rot
    • Small round, blackish specks on surface of stalk rind and pinkish-red discoloration inside the stalk
    • Overwinters in crop residue and infects the plant in warm, wet conditions
    • Hybrid resistance is uncommon, avoid other stresses such as insect leaf tissue damage to reduce likelihood of gibberella infection
  • Anthracnose Stalk Rot
    • Shiny black lesions on stalk with black fungal material just beneath the surface
    • Overwinters in residue and requires high humidity, warm temperatures and expended periods of cloudy weather favor the disease
    • Look for hybrids with stalk rot resistance, avoid stress and consider tillage to bury crop residue
  • Fusarium Stalk Rot
    • White fungal growth on the outside of the stalk with pink or salmon color on interior stalks, feels spongy when performing squeeze test
    • Dry weather prior to silking and warm, wet weather after silking can increase infection rates0
    • Overwinters in crop residue, hybrids with resistance to other stalk rots might carry some resistance to fusarium