Agronomic biofortification of plant foods with minerals, vitamins and metabolites with chemical fertilizers and liming.

Agronomic biofortification is the fastest and less expensive method to overcome micronutrient deficiencies of iron, zinc and selenium. Fertilizers also help in augmenting vitamins and other food qualities. Although fertilizers have contributed vastly toward increase in food production, their misuse or rather abuse has led to severe environmental pollution. These include eutrophication of sea and inland waters, depletion of ozone layer and global warming. Fertilizers also contribute toward an increase in mineral and vitamin content in crops. Micronutrient fertilizers can increase concentration of iron and zinc in grains and vegetables, the deficiencies of which are widespread in Asian and African countries. Nitrogen fertilization can increase content of carotene in carrots. Liming is reported to increase calcium concentration in vegetables. Similarly, sulfur (S) fertilization can increase the content of S-containing amino acids in grains, glucosinolates in many Brassica species and alliin content in garlic and onion. As regards, vitamin C, there are increases as well decreases due to nitrogen reported in literature; the minor decreases are well compensated by an increase in yield. Potassium fertilization is reported to increase vitamin C content in some vegetables. Nitrogen fertilization increases nitrate content in vegetables, which is considered harmful, but some recent reports suggests advantages of this increase. Instead of blaming fertilizer for quality of food and environmental degradation, sincere efforts are needed toward its judicious application and avoiding its overuse or abuse and biofortification is the best suited method. [ABSTRACT FROM AUTHOR]