Biofortification of Maize (Zea mays)

Abstract

AbstractThe production and consumption of maize (Zea mays) are the highest for human food as well as animal feed. Maize lacks essential amino acids (lysine, tryptophan), micronutrients (Fe, Zn, Mn, Se, I), and various vitamins (vitamin A). Therefore, the issue of malnutrition is still prevalent in nations where maize is the staple crop and has led to the impairment in the growth and development of the ever-increasing population, ultimately causing significant economic losses. A combinatorial approach is being used to overcome this issue which includes dietary diversification and food supplements. Regardless of these approaches, maize biofortification holds immense potential, proving to be a sustainable and cost-effective solution to malnutrition. Here, we describe conceivable methods for developing biofortified maize cultivars to curb global malnutrition. Agronomic biofortification includes applying fertilizers having concoctions of sulfates, hydrates, and oxides to fortify maize in its edible parts. GWAS and QTL mapping have so far helped a lot in identifying genetic elements controlling a particular phenotype. Hence, modern breeding techniques have improved the maize germplasm but still face the huge challenge of low yield potential and environmental impacts. The underlying molecular mechanisms which help in the uptake and deposition of these essential micronutrients in the maize grain have been studied in detail. Recently, the transgenic approach has been most widely used as it gives a comprehensive analysis of the regulatory pathways. Bacterial as well as plant genes have been expressed in maize, but despite the massive potential, commercial production through this approach has not been put to reality yet. The most advanced and flexible approach which uses CRISPR/Cas9 has opened up new avenues of genome editing for multiple purposes. The economic and social constraints of every approach have also been discussed.KeywordsBiofortificationMalnutritionMicronutrientsMarker-assisted breedingQTL mappingCRISPR/Cas9