Poor stands in the field are associated with weather stresses resulting in some seeds not germinating or delayed in germination, resulting in plants much later than adjacent plants. We look at the plant as a whole, but most of the damage is being done at the cellular level. Plant cells are not empty structures but are the vessels where the real action of the plant occurs. Membranes, those long chains of lipids and proteins, not only form barriers to control what enters the cell and its organelles like mitochondria, chloroplasts and ribosomes but also membranes are major components of these structures. These are sites where all of the corn plant’s life must occur. Maintenance of integrity of the membranes within the corn embryo cell membranes is critical to timely germinations.
Cell membranes are especially vulnerable to damage during the drying process of the seed and then the expansion after imbibition. They do self-repair, a process requiring both heat energy and supply of carbohydrate energy. Embryos removed from the endosperm will germinate, producing a shoot and root, but adequate heat energy must be supplies and no invasion of pathogens. But they need the stored energy from the endosperm to push through the soil to emerge and receive fresh supply of carbohydrates from photosynthesis.
Cool wet conditions in the field will result in inadequate repair of cell membranes, delaying the emergence of some seedlings. It may be greater with some individual seeds than others because of some seed production and handling conditions or some specific field situations.
More about membranes can be found in the Corn Journal in the search.
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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.