Skip to Left navigation Skip to Main content Skip to Footer

University of Minnesota Extension

Extension > Garden > Diagnose a problem > What's wrong with my plant? > Vegetable > Sweet corn > Poor kernel fill

Print Icon Email Icon Share Icon

Sweet corn > Ear > Poor kernel fill

1 of 3
  • Image: Fusarium Wilt 1

Poor Pollination

  • Reduced kernel fill can range from only a few open areas where kernels are missing to almost the entire cob void of kernels reduced kernel fill
  • Common after periods of extreme heat or in gardens with too few plants for cross pollination
  • More information on Poor Pollination
2 of 3
  • Image: Bottom Rot/Head Rot 1
  • Image: 2
  • Image: 3

Northern and Western Corn Rootworm
Diabrotica barberi and Diabrotica virgifera virgifera

  • Adult corn rootworm beetles feed on corn silk which can reduce the number of kernels on the cob
  • In severe cases, very few kernels will be produced on the cob
  • Larvae feed on roots of corn, which can cause plant to fall over, or "lodge"
  • Northern corn rootworm adults are about 3/16th inch long and pale green; western corn rootworm adults are about 5/16 inch long, yellow to green in color with three black stripes running along the back of the beetle
  • More information on Northern and Western Corn Rootworm
3 of 3
  • Image: Club Root 1
  • Image: Club Root 2

Dwarf mosaic and maize chlorotic dwarf

  • Leaves have light and dark green mottling or streaks
  • Infected plants are stunted and may produce many tillers
  • Plants may not produce an ear, or ear is poorly developed
  • More information on Virus

Don't see what you're looking for?