Biofortification of Wheat Using Current Resources and Future Challenges

Wheat is the second most significant staple food grain crop after rice; however, its grains mostly contain suboptimal levels of provitamins, proteins, and essential micronutrients, including zinc, iron, selenium, and iodine. However, during processing, wheat flour is enriched or fortified with several required nutrients. The most reasonable, long-lasting, and viable solution for this problem is biofortification that can be performed through either agronomic approaches, breeding efforts, or transgenic techniques. Agronomic fertilization techniques for wheat biofortification include basal application, foliar spray, and seed priming with the appropriate nutrient sources. Recently, various potent bacterial strains have been used, and these techniques can be used in combination with agronomic and genetic techniques to significantly enhance the density of the nutrients that require to be supplemented in wheat grains. Compared to agronomic approaches, breading techniques are more sustainable and include conventional and markerassisted breeding. Transgenic approaches for micronutrient biofortification of wheat include modulation of the gene expression of transporters to improve the absorption rate and assimilation capability of the wheat plant while lowering antinutrient content. In this chapter, along with the possible techniques of biofortification, we discuss the mode of uptake and deposition of the desired nutrients in the grain at molecular and physiological levels. We discuss the possible wheat genomic obstacles that hinder wheat biofortification as well as the economic and social challenges for the release of biofortified wheat.