Among the features of corn that makes it a great carbohydrate crop is the C4 photosynthetic system that allows utilization of higher light intensity than C3 photosynthesis plants. We have further selected genetics that combine large kernel numbers with a strong draw of carbohydrates to each kernel, especially in days 10-50 after pollination. The combination of high response to light intensity, strong draw of carbohydrates to the ear and high numbers of plants per acre can result in maximum grain yield per unit of land area.
Of course, multiple factors interact for this to happen. Minerals and water to allow maximize plant structure and function and leaf area per land area are major. A balance in distribution of available carbohydrates to allow continual living root tissue as well as the transport of carbs to the kernels is essential especially during those 50 days.
And then there is importance of light to drive the photosynthesis. Smoke haze has been a notable feature of the 2021 summer in the western USA corn belt. This haze reduces the intensity of sunlight by scattering the light waves. This could have an affect beneficial to corn in that it may overcome the shadowing from leaves, allowing more light penetration to the lower leaves in the canopy. On the other hand, lower intensity of wave lengths in critical to photosynthesis in a C4 plant like corn could reduce total carbohydrate production in the plant.
Reduction in total photosynthate in a corn plant plus genetics that favor strong movement of available carbs from leaves and elsewhere to the developing kernels increases to the probability of root deterioration. This deterioration leads to vulnerability to invasion by microorganisms and eventual inability to transport water from soil to upper plant. This will lead to wilting of the plant and stalk rot.
A lot of dynamics interact a corn crop and the 2021 environment will include smoke haze from the forest fires in Western USA.
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.