P&PDL Picture of the Week for
June 28, 2004

Over-Extended Mesocotyls & "Floppy Corn"

Bob Nielsen, Extension Corn Production Specialist, Purdue University

The term "floppy corn" simply describes a plant that has fallen over because of the absence of an established nodal root system. Affected plants may survive if the mesocotyl remains intact and subsequent nodes of roots establish themselves into the soil. If the mesocotyl breaks before successful establishment of subsequent nodal roots, the plant dies. The causes of the poor nodal root development varies from situation to situation.

This image gallery depicts "floppy corn" and associated symptoms of over-extended mesocotyls from two no-till fields. For more information, please see the accompanying article at http://www.kingcorn.org/news/articles.04/FloppyCorn-0624.html

Click image to enlarge

Two floppy corn plants

Two floppy corn plants

Closer view of dead nodal roots  of flopped corn plant

Closer view of dead nodal roots
of flopped corn plant

Flopped plant near death

Flopped plant near death

Broken mesocotyl of flopped plant near death

Broken mesocotyl of flopped plant near death

Crown exposed 1/2 to 3/4 inch above ground, nodal roots dead or dying, mesocotyl alive.

Crown exposed 1/2 to 3/4 inch above ground, nodal roots dead or dying, mesocotyl alive.

Same plant, illustrating that seed depth was technically acceptable, about 1.5 inches below soil surface.

Same plant, illustrating that seed depth was technically acceptable, about 1.5 inches below soil surface.

Purdue Plant & Pest Diagnostic Lab Purdue Cooperative Extension Service