Wheat Biofortification for Enhancing Iron, Zinc, and Protein: The Role of Mutation Breeding

Implementing Marker-Assisted Selection for Biofortification of Staple Crops With Iron, Zinc, and Provitamin A: A Review

Micronutrient malnutrition remains a major global nutrition problem, particularly in populations whose diets depend heavily on staple crops. Iron (Fe), zinc (Zn), and vitamin A deficiencies can adversely affect growth, immunity, cognitive development, and overall health. Crop biofortification provides a sustainable breeding-based strategy for increasing the concentration of essential nutrients in commonly consumed foods. This review examines the application of marker-assisted selection (MAS) in the development of Fe-, Zn-, and provitamin A (PVA)-rich staple crops. Relevant peer-reviewed literature, scientific reviews, and institutional publications were examined using major academic databases and search platforms, including PubMed, Scopus, Web of Science, and Google Scholar. Particular attention was given to the genetic basis of micronutrient accumulation, molecular markers, marker-assisted backcrossing, marker-assisted recurrent selection, gene pyramiding, and recent applications in maize, rice, wheat, pearl millet, cassava, and other staple crops. Evidence from breeding programs indicates that MAS can improve the efficiency of selecting favorable alleles and can facilitate the introgression and combination of nutrient-associated genes and quantitative trait loci (QTLs). Major targets include crtRB1 and lcyE for PVA accumulation in maize, genomic regions associated with grain Fe and Zn in cereals, and nutrient-related loci in rice and cassava. Nevertheless, the effectiveness of MAS can be constrained by the quantitative inheritance of micronutrient traits, genotype × environment interactions, marker–gene recombination, limited genomic resources in some crops, and differences in nutrient bioavailability. Future breeding strategies should integrate MAS with genomic selection, high-throughput phenotyping, speed breeding, gene editing, and climate-resilient breeding. Overall, MAS represents an important component of modern biofortification programs and can contribute to the development of nutritionally improved, productive, and farmer-acceptable staple crop varieties.

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

Iron Biofortification in Maize: A Review of Recent Progress and Future Prospects`

Iron Deficiency (ID) continues to be one of the main hidden hunger issues in the world today, impacting billions of people and becoming a major hurdle for human food security and health. Maize (Zea mays L.) is one of the widely cultivated and consumed cereal crops and thus has the potential to be an important target for iron biofortification to improve dietary iron intake, especially in cereal-centric diets. During the last decade efforts have been undertaken to understand the physiological, agronomic, genetic and molecular aspects associated to Fe uptake, transport, accumulation and bioavailability in maize. The recent progress in biofortification of maize with iron is reviewed, with a focus on soil Fe, strategy II Fe acquisition, Fe transport and Fe homeostasis and their effects on the accumulation of Fe in grain. Modern breeding technologies including conventional breeding, quantitative trait locus (QTL) mapping, genome wide association studies (GWAS), genomic selection, transgenic technologies and CRISPR/Cas mediated genome editing are discussed critically along with the recent advances of agronomic biofortification including soil and foliar fertilization, seed priming, nano-fertilizers and organic amendments. The review also focusses on the new functions of plant growth-promoting rhizobacteria (PGPR), microorganisms producing siderophores and arbuscular mycorrhizal fungi in the improvement of the iron availability and uptake in a sustainable biological way. Moreover, recent advances in multi-nutrient biofortification, precision agriculture, omics, artificial intelligence and genome-assisted breeding are explored as tools to facilitate the acceleration of the development of biofortified maize cultivars rich in iron. However, a number of challenges still exist, such as the bioavailability of iron, genotype × environment interaction, soil limitations, climate change, and regulation and farmer adaptation. It is concluded that the combination of molecular breeding, microbial-assisted technologies, precision agriculture and agronomic management are most likely to lead to the development of nutritionally improved maize varieties which will reduce the prevalence of ID and help to achieve sustainable FSNSS. Finally, future research priorities are seen which will assist in the efficient development and scale-up of iron-biofortified maize.

Role of Biostimulants in Wheat: Nutritional Quality and Resistance to Abiotic Stresses, a Systematic Review

Wheat is a major staple crop, and improving its productivity and grain quality is essential to meet rising global food demand. Biostimulants have attracted growing interest because they can enhance nutrient use efficiency, improve tolerance to environmental stresses, and support crop performance without acting as conventional fertilizers, yet a focused synthesis of their effects on wheat remains limited. Following a systematic search of Scopus and Web of Science (2000–2026), this review synthesizes 52 primary studies on microbial and non-microbial biostimulants in common and durum wheat, addressing grain yield, nutritional quality, and resilience to drought, salinity, heavy metals, and temperature extremes. Across studies, 88% reported significant positive effects and none reported a consistent negative effect; grain yield increases ranged from +6% to +123%, with parallel improvements in grain protein and micronutrient biofortification, notably zinc and iron. Microbial biostimulants, especially bacteria and microbial consortia, produced the largest but most variable gains, whereas non-microbial products gave more moderate and consistent responses. Benefits were greatest under low nitrogen, drought, and saline conditions and in nutrient-poor soils, and were modulated by wheat genotype and product dose. Biostimulants are promising tools for sustainable wheat production, though standardized field trials and reporting are still needed.

Integrating genetic and agronomic fortification improves zinc, iron, and protein concentrations in rice grain: A meta-analysis

Rice, consumed by half of the world’s population, is inherently low in zinc (Zn), iron (Fe), and protein. We compiled data from 245 studies across 34 countries to evaluate the impact of genetic, agronomic, and processing interventions on rice grain Zn, Fe, and protein concentrations. Zn-biofortified cultivars had 9.8% higher grain Zn concentrations than non-biofortified cultivars, while Fe-biofortified cultivars did not exhibit a significant improvement in Fe content. In the absence of Zn and Fe fertilization, the probability of achieving the breeding target concentrations of Zn (28 mg kg−1) and Fe (15 mg kg−1) was only 4.0% and 10.5%, respectively in white (polished) rice. On the other hand, Zn and Fe fertilization increased the probability of achieving the same targets in white rice by 41.3% and 67.7% for Zn and Fe, respectively. Milling and polishing of brown rice grains reduced Zn, Fe, and protein concentrations by 21%, 70%, and 6.5%, respectively. Our findings emphasize the need for the combined use of genetic and agronomic fortification and the consumption of parboiled rice to attain desired health impacts.

Biofortification Strategies to Enhance Nutrient Content in Crops

A sustainable way to combat hunger is biofortification, which entails using genetic engineering or traditional breeding to increase the nutritional content of basic crops. The importance of biofortification in preventing world hunger is covered in this abstract, along with a summary of the methods used to enrich crops with vital nutrients. The efficacy of several biofortification techniques, such as traditional breeding, transgenic approaches and agronomic practices, in raising the concentrations of essential elements like iron, zinc, vitamin A and vitamin C in staple crops including rice, wheat, maize, and cassava is being investigated. This abstract highlights the success stories of biofortified crops, such as iron and zinc-enriched beans, vitamin A-rich rice, and selenium-fortified wheat. These crops have demonstrated the potential to contribute significantly to alleviating nutrient deficiencies, especially in regions where traditional diets lack essential micronutrients. It also highlights the necessity of multidisciplinary cooperation between farmers, policymakers, nutritionists, breeders, and plant scientists in order to enhance global public health outcomes and hasten the adoption of biofortified crops. Biofortification stands as a promising avenue for enhancing crop nutrient content and addressing global malnutrition challenges. Continued research, investment, and collaboration are crucial to advancing biofortification strategies and realizing their potential to improve the nutritional status of populations worldwide.