BIOFORTIFICATION THROUGH MODERN BREEDING: GENETIC AND GENOMIC STRATEGIES FOR NUTRITIONAL SECURITY

Abstract

Even though countries like India and China has achieved the sustainable food production for meeting the food requirements of their respective countries, still some section of people are suffering from micronutrient malnutrition or hidden hunger due to micro nutrient deficiency, often of iron, zinc, folate or vitamin A. The staple cereals, legumes, and root crops are bulk in dietary energy yet are poor sources of several micronutrients. To increase the nutrient density in the food crops, modern breeding techniques are introduced to complement supplementation and industrial fortification. This review discusses about the genetics and genomics of crop biofortification from classical quantitative trait locus (QTL) mapping and marker-assisted selection through genome-wide association studies (GWAS), genomic selection and CRISPR-Cas genome editing. It examines the molecular architecture of mineral homeostasis (ZIP, NRAMP, YSL, VIT, ferritin, and nicotianamine synthase gene families), Provitamin A carotenoid pathway (crtRB1 and IcyE), and endosperm protein quality loci (opaque 2, opaque 16). It also discusses about the emerging integration of genomic selection with speed breeding and multi-omics/pan-genome resources. While the single nutrient biofortification is now a scalable technique for several staple crops, the merging techniques focus on stacking multiple micronutrient and quality traits within high-yielding, climate-resilient through precision genomics.