Water moves from soil into root tissue by diffusion, going from higher concentration in the soil into the cells with water concentration diluted by sugars and minerals. Each mineral likewise is absorbed according to its own concentration inside and outside of the root cells. Movement of water and the mineral solutes flow upwards because of water cohesiveness and the removal of water via transpiration through leaf stomates.
Minerals pulled along with the water are essential to each biochemical process, from formation of cell components to the function of those components. Not only the structures but also manufacture of products integrate the minerals are dependent upon the supply of minerals carried from soil with water.
Stomatal pores are open during the day as the result of photosynthesis and unique shape of guard cells of the stomates (https://www.cornjournal.com/corn-journal/corn-leaf-epidermis). Evaporation of water through open stomata is determined by relative humidity immediately outside the openings. Transpiration is greatest if immediate outside humidity is low. Water movement from roots to leaves is greatest in a dry daytime environment. It follows that mineral movement from soil to leaves that is greatest with drier daytime environments. This becomes especially significant during growth stages of corn as minerals become tied up in cell structures but some elements such as nitrogen, potassium and phosphorus are essential components of enzymes essential to basic photosynthesis and respiration needed continued cell function until completion of the corn plant’s life cycle.
Among the genetic differences in corn varieties is efficiency of water absorption. These must involve structural differences affecting total roots volume and direction of growth. Some have a deeper root and some more spreading than other varieties. Each may be more suitable for specific soil conditions and a season’s weather. Varieties must also differ in vascular structure affecting the efficiency of movement of water upwards.
Varieties of corn also must vary in number of stomates. More stomates may result in ability to absorb more carbon dioxide for photosynthesis and also more movement of water with minerals from the soil but this advantage may be a disadvantage during drought weather. Variety features such as more leaf area is advantageous for total photosynthesis but may result in higher water loss because of more stomates.
Water and mineral movements are affected by a combination of plant structure and environment ultimately expressed at the end of the growing season by grain yield.
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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.