Agronomic biofortification as a means of enriching plant foodstuffs with iodine

Iodine is indispensable in the diet of humans and other mammals and iodine deficiencies cause serious illnesses. The content of iodine in food (with the exception of marine foodstuffs) does not meet the nutritional needs of humans, and for this reason prophylactic iodination of salt is currently carried out in many countries. Biofortification of plants with iodine can become a widespread, alternative means of supplying iodine-rich foods. In the present study, we discuss the main issues related to the cultivation of plants enriched with iodine. We describe the effect of various forms of iodine fertilizer on crops, such as natural iodine sources, organic iodine, iodate and iodide salts, as well as ways of biofortifying crops: fertigation, foliar and soil application, and by hydroponics. Effective biofortification of plants with iodine increases its concentration to levels corresponding to human nutritional requirements whilst preserving the desirable eating qualities of the plants. Because each species reacts in a specific manner to a particular chemical form of iodine application, fertilization and cultivation methods, and other conditions, the development of proper cultivation technologies is essential to bring about widespread biofortification with iodine.