Common Ear Rots | Corn | Pioneer

Common Corn Ear Rots

Diplodia Ear Rot (no mycotoxins)

Wet weather during grain fill and upright ears with tight husks promote Diplodia
Diplodia may cause ear rot, stalk rot or seedling blight
Corn is only known host
Wet weather plus moderate temperatures allow infection to occur if spores are present during early silking to two to three weeks after silking
Diplodia is highly dependent on quantity of infected, unburied corn residue (stalks, cobs and kernels)

Corn ear damaged from diplodia ear rot

Gibberella Ear Rot (mycotoxins may occur)

Infects other cereals – causes head scab of wheat
Overwinters in infected crop residue
Spores are spread from crop residue to corn ears by wind and rain splash
Infection of corn ears occurs through young silks
Infection favored by cool, wet weather during and after pollination
(optimum temps 65 to 70 F)

Corn ear damaged from gibberella ear rot

Fusarium Ear Rot (produces mycotoxins)

Most common fungal disease on corn ears
Fungi survive on residue of corn and other plants
Most severe when weather is warm and dry
Disease enters ear primarily through wounds from hail or insect feeding
Scattered or groups of kernels are typically affected
Mold may be white, pink or salmon-colored
Infected kernels may turn tan or brown
"Starburst" pattern often associated with the disease

Corn ear damaged from fusarium ear rot

Aspergillus Ear Rot (mycotoxins may occur)

Most common under drought conditions, high temperatures (80-100 F) and high relative humidity (85%) during pollination and grain fill
Gray-green, olive, yellow-green or yellow-brown powdery mold growth on and between kernels
Surface mold can develop anywhere on the ear
Symptoms are often found at damaged areas of ear

Corn ear damaged from aspergillus ear rot