Growth of the corn plant, beginning with germination and emergence from the soil, is mostly due to cell elongation. This requires a combination of water pressure within cells, softened cell walls and eventual production of new cell wall components. The water pressure is basically a physical phenomenon. Water moves through cell walls and membranes from a high concentration of water (i.e. few solutes) to the low concentration within the cells. The physiological components such as production of hormones related to softening of cell walls and building of new membranes and other components of the expanded cells are more dependent on metabolism. This can be affected by outside factors such as temperature.
This conflict between water pressure on cells and difficulty with metabolism at low temperatures can cause slow emergence in wet, cold soils and, occasionally, some deformed seedlings that never do emerge. Damage can also lead to more infection by the few fungi such as Pythium species that are favored by low temperatures.
It is not well understood why these factors seems to result in twisted seedlings growing from a few seeds whereas adjacent seeds produce normal emergence. It could be because the water is pressuring the cell elongation but the metabolism is unable to adequately accommodate with production of cell wall materials. Were the individual seeds damaged, soil components surrounding those seeds causing growth stress, or growth hormone herbicide concentration or pathogens involved? It does become difficult to troubleshoot because it often is a complicated mix of variables. Regardless, the late-emerging plants rarely perform as well as the early-emergers. Sometimes this start of the season is forgotten when final yields are compared 6 months later.
About Corn Journal
The purpose of this blog is to share perspectives of the biology of corn, its seed and diseases in a mix of technical and not so technical terms with all who are interested in this major crop. With more technical references to any of the topics easily available on the web with a search of key words, the blog will rarely cite references but will attempt to be accurate. Comments are welcome but will be screened before publishing. Comments and questions directed to the author by emails are encouraged.