Corn and Food Security

Corn is categorized as a Strategy II, graminaceous plant. Graminaceous plants depend largely on molecules known as phytosiderophores in the acquisition of iron and other micronutrients (1). Soluble forms of micronutrients are readily available throughout calcareous soils in the world. Soils can be categorized as calcareous when they are very alkaline in nature. Calcareous soil has a basic pH which causes minerals such as Fe(III), or the soluble form of iron, to be reduced into Fe(II), or the insoluble form (1). The problems with micronutrient accessibility, especially iron, causes issues with corn health and composition. Without the correct amounts of nutrients available, corn yields will decrease in size and nutritional value. With corn being a food, energy, and fuel source, the health of this plant is crucial for society.

Strategy II plants are capable of uptaking insoluble forms of nutrients by the secretion of phytosiderophores. Phytosiderophores are classified as nutrient mobilizing compounds which the plant secretes into the rhizosphere—the small area surrounding a plant’s roots where symbiotic bacteria live and nutrient acquisition takes place. Phytosiderophores bind to divalent cations such as Fe(II), Ca(II), or Mg(II) that the plant necessitates and facilitates its entrance back into the plant. Once inside the plant, the nutrient, in this case iron, is oxidized into the proper oxide (1). The plant is then able to utilize the nutrient and distribute it throughout.

For this project, corn deficiencies in iron were analyzed. After going through a period of iron deficiency, plants will develop a disease known as Iron Chlorosis. This refers to the yellow discoloration of leaves, stems, and roots. The chlorosis causes stunted growth and lessens nutritional value from the crop yields. Iron Chlorosis is more likely to occur in calcareous soils because of the insolubility of iron available (2). As it is, roughly 30% of Earth’s measured soil is categorized as calcareous. Calcareous soils are alkaline in nature which means the classification is more common for soils near alkaline deposits such as lime. In Indiana, it is estimated that 85% of all soil is calcareous (4).

The health and prosperity of corn affects the United States specifically in an increasingly large amount of ways. The United States focuses heavily on the corn industry with around ninety percent of the grain produced being a strain of corn (3). Apart from the industry, the average American eats four pounds of byproducts of corn a day. Corn is utilized as feed for cattle and directly ties into the human meat consumption. It’s calculated that sixty percent of all United States corn is reserved as feed (3). Apart from the food sector that involves corn, an entire industry of ethanol fuel has emerged. Ethanol is estimated to be added to seventy percent of the gasoline in modern gas stations (3).