Accelerating iron biofortification in millets: progress, challenges, and future prospects

Integrating conventional breeding, omics, and CRISPR-based genome editing can overcome genetic and antinutrient constraints, enabling efficient iron biofortification of millets for sustainable and nutrition-secure food systems. Iron (Fe) deficiency remains one of the most widespread forms of micronutrient malnutrition. Biofortification of staple crops has emerged as a particularly sustainable and scalable strategy to combat this issue. Millets are nutrient-dense staple cereals with exceptional nutritional quality and climate resilience. However, genetic variations and the presence of antinutrients limit Fe content in millets, which highlights the necessity of advancing biofortification strategies. This review examines the present state of multi-dimensional strategies and discusses the future prospects for efficient iron biofortification in millets. We analyzed the efforts made for Fe biofortification in millets, ranging from conventional breeding practices to next-generation molecular approaches. Recent advances in omics have enhanced understanding of Fe uptake, transport, and storage in millets. Furthermore, CRISPR/Cas-based genome editing is discussed for the regulated expression of key Fe-transporter genes and targeted knockout of genes responsible for antinutrients. A multidisciplinary approach is essential to develop high-yielding and Fe-rich millet varieties that can contribute to sustainable nutrition security.