Biofortification Of Staple Crops Research Articles

Social norms, nutrition messaging, and demand for biofortified staple crops: Evidence from a discrete choice experiment in Ethiopia

Social norms, nutrition messaging, and demand for biofortified staple crops: Evidence from a discrete choice experiment in Ethiopia

Selenium biofortification impacts nutritional composition and storage proteins in wheat grains

Selenium (Se) biofortification of staple crops can be used as a valuable pathway to prevent Se deficiency in human diet. In this study, a pot experiment was performed under semi-controlled conditions to investigate the response of indigenous wheat cultivars to different Se concentrations (0 to 100 mg L-1) and to also assess the effects of Se foliar application on the storage proteins in wheat grains. A linear increase in Se concentrations in the grains of various wheat cultivars was observed (up to 158 μg kg-1) in response to Se application rates. It was observed that Gandum-1, Fakhar-e-Bhakkar-17, Ujala-16 and Anaj-17 were the most responsive wheat cultivars to Se application rates and accumulated the highest Se concentrations in grains. Though Se foliar treatments did not significantly affect the wheat yield, a highly significant correlation was observed between the Se application rates and the concentration of mineral nutrients (iron, zinc, calcium and potassium). Moreover, the exogenous Se supply considerably enhanced the concentrations of different storage proteins viz. albumin, globulin, prolamin and glutelin in wheat grains. The target hazard quotient of all Se application rates was found less than the toxic levels. In conclusion, wheat cultivars differ in their ability to accumulate Se concentrations in grains and biofortifying the most responsive wheat cultivars could be used as an efficient agronomic strategy to overcome widespread Se deficiency in human population.

Heterogeneous preferences and market potentials for biofortified foods in sub-Saharan Africa: Evidence from Nigeria

In recent time, biofortified staple crops have been bred to correct for Vitamin A deficiency in sub-Saharan African countries. In this study, we used a cross sectional preference data from a survey of 750 food buyers in Nigeria to access heterogeneous preferences and market potentials for biofortified foods. We used Hybrid Latent Class (HLC) framework to jointly examine respondents’ choice component with their responses to attitudinal questions preventing potential endogeneity and measurement error. The result indicate that consumers are willing to pay an extra premium of ₦l50 for biofortified garri over the normal price of white or yellow garri for health gains, thus suggesting that there is a potential market for biofortified foods in Nigeria. Our results show that consumers who had higher preference for biofortified foods attached a greater preference for higher vitamin A content of the product. We also observed that respondents were faced with regional heterogeneity. We observed that respondents in the urban area were more willing to pay for biofortified food quality attributes. We observed that in order to increase the demand for biofortified foods in Nigeria, a key strategy is to ensure that consumers have access to the products. In addition, the public should be better informed on health implication of consuming foods fortified with vitamin A such as biofortified products.

Predictors of vitamin A rich food consumption among women living in households growing orange-fleshed sweetpotatoes in selected regions in Uganda.

Vitamin A deficiency (VAD) has serious public health consequences including morbidity and mortality for populations in low and middle-income countries (LMICs), especially for children under 5 years and pregnant women. LMICs are at greater risk of VAD, in part due to low levels of consumption of vitamin A-rich foods most of which are plant-based, such as orange-fleshed sweet potatoes (OFSP), with lower bioavailability than animal sources of the vitamin A. Food-based approaches such as biofortification of OFSP, including promoting the consumption of vitamin A-rich biofortified staple crops, has been shown to be potentially effective in improving the status of vitamin A and other micronutrients. This study examined vitamin A-rich food consumption and its predictors among women of reproductive age from OFSP-growing households in two regions of Uganda. A cross-sectional survey was conducted among 617 OFSP growing households, focusing on women in the reproductive age group from the northern and eastern regions of Uganda. Households were not receiving any VAD-related intervention at the time of the survey. Quantitative data included vitamin A-rich food consumption, knowledge on vitamin A, and rich food sources dietary intake, using a 7-day food frequency questionnaire. Vitamin A consumption and risk of deficiency were estimated using the Hellen Keller International guide. The majority of women in this study were either pregnant (80%) or lactating (17%). More than 70% of the study population had a weighted vitamin A rich food consumption mean score of <6 days per week, indicating a high risk of VAD. Knowledge about vitamin A [b (SE) = -0.18 (0.50), p < 0.001] was significantly and inversely associated with vitamin A rich food consumption. Components of food insecurity such as availability, affordability, utilization, and changing food preferences may contribute to the unexpected inverse relationship between knowledge and consumption of vitamin A rich foods. Scaling up biofortified food initiatives, including OFSP, can improve consumption of vitamin A rich foods with effective strategies to comprehensively address consumption barriers such as lack of nutrition education, cooking skills, and storage facilities, as well as low production levels and perceived contamination of biofortified foods.

Metal tolerance gene family in barley: an in silico comprehensive analysis

Metal-tolerance proteins (MTPs) are divalent cation transporters that play critical roles in metal tolerance and ion homeostasis in plants. However, a comprehensive study of MTPs is still lacking in crop plants. The current study aimed to comprehensively identify and characterize the MTP gene family in barley (Hordeum vulgare, Hv), an important crop. In total, 12 HvMTPs were identified in the barley genome in this study. They were divided into three phylogenetic groups (Zn-cation diffusion facilitator proteins [CDFs], Fe/Zn-CDFs, and Mn-CDFs) and further subdivided into seven groups (G1, G5, G6, G7, G8, G9, and G12). The majority of MTPs were hydrophobic proteins found in the vacuolar membrane. Gene duplication analysis of HvMTPs revealed one pair of segmental-like duplications in the barley genome. Evolutionary analysis suggested that barley MTPs underwent purifying natural selection. Additionally, the HvMTPs were analyzed in the pan-genome sequences of barley (20 accessions), which suggests that HvMTPs are highly conserved in barley evolution. Cis-acting regulatory elements, microRNA target sites, and protein–protein interaction analysis indicated the role of HvMTPs in a variety of biological processes. Expression profiling suggests that HvMTPs play an active role in maintaining barley nutrient homeostasis throughout its life cycle, and their expression levels were not significantly altered by abiotic stresses like cold, drought, or heat. The expression of barley HvMTP genes in the presence of heavy metals such as Zn2+, Cu2+, As3+, and Cd2+ revealed that these MTPs were induced by at least one metal ion, implying their involvement in metal tolerance or transportation. The identification and comprehensive investigation of MTP gene family members will provide important gene resources for the genetic improvement of crops for metal tolerance, bioremediation, or biofortification of staple crops.

The Effect of Adding Bambara Groundnut (Vigna subterranea) on the Physical Quality, Nutritional Composition and Consumer Acceptability of a Provitamin A-Biofortified Maize Complementary Instant Porridge

Undernutrition is prevalent in developing regions, particularly sub-Saharan Africa (SSA), especially among children under five. Biofortification of staple crops and using indigenous and traditional crops could be an affordable and sustainable strategy together with other existing strategies to reduce undernutrition. This study aimed to determine the effect of adding bambara groundnut (BGN) on the physical quality, nutritional composition and consumer acceptability of a provitamin A-biofortified maize (PVABM) complementary instant porridge. The PVABM flour was substituted with flour of either red or brown BGN variety at 0, 10, 20 and 30% (w/w) levels. The composite flours were used to make an instantized complementary porridge. The physical quality (texture, color, water absorption capacity (WAC), solubility index (SI) and swelling volume (SV)) of the grains and the composite complementary instant porridges were assessed. Nutritional analysis was conducted using standard AOAC methods. A 55-member consumer panel evaluated the acceptability of the porridge samples using a nine-point hedonic scale. The firmness, WAC, SI and SV decreased with increasing concentration of flour of either of the BGN varieties. The decrease in SV would positively affect the porridge quality as nutrient density and viscosity decreased. The protein, fat, fiber and total mineral (ash) content of the porridges increased with an increase in either BGN variety. There was no significant difference (p &gt; 0.05) in the overall acceptability of the BGN–PVABM composite porridge samples and the porridge without BGN (control). The improved nutritional composition and positive consumer acceptability of BGN–PVABM are encouraging as consumption could contribute to the alleviation of nutrient deficiencies, including protein-energy malnutrition and mineral deficiencies, especially in SSA.

Genome Editing and Protein Energy Malnutrition.

Protein-energy malnutrition is a state of disordered catabolism resulting from metabolic derangements or starvation. It is associated with chronic disease, hypoglycemia, hypothermia, serious infections, and even an increased prevalence of morbidity and mortality in countries with poor socioeconomic or environmental factors. Adequate food administration is essential to satisfy the main caloric and nutritional demands of humans. The most significant factors seen in the development of protein-energy malnutrition in areas of high incidence, such as underdeveloped countries, are inadequate food and nutrient supplies. It has been well established that one of the strategies to alleviate undernourishment is the biofortification of staple crops. This is because vegetables and plants are significant sources of crucial nutrients for human growth and development. To enhance plant nutrition, recent tactics aim to formulated balanced and diverse diets with acceptable levels ofvitamins and minerals that benefit human health. New advances in plant biotechnology and animal productivity could control key enzymes in several metabolic pathways, enriching important nutrients such as iron and vitamins and decreasing the content of disadvantageous compounds such as acrylamide-forming amino acids and phytic acids. Numerous biofortified crops such as rice, maize, and wheat have been created to resolve the problem of nutrition deficiencies. Some examples of these methodologies are genome editing engineered nucleases, transcriptional activator-like effector nucleases, zinc finger nucleases, and clustered regularly interspaced short palindromic repeats and associated Cas9 endonuclease which have been created and widely studied for their application, efficiency, and specificity.

A two-gene strategy increases iron and zinc concentrations in wheat flour, improving mineral bioaccessibility.

Dietary deficiencies of iron and zinc cause human malnutrition that can be mitigated by biofortified staple crops. Conventional breeding approaches to increase grain mineral concentrations in wheat (Triticum aestivum L.) have had only limited success, and our understanding of the genetic and physiological barriers to altering this trait is incomplete. Here we demonstrate that a transgenic approach combining endosperm-specific expression of the wheat VACUOLAR IRON TRANSPORTER gene TaVIT2-D with constitutive expression of the rice (Oryza sativa) NICOTIANAMINE SYNTHASE gene OsNAS2 significantly increases the total concentration of zinc and relocates iron to white-flour fractions. In two distinct bread wheat cultivars, we show that the so called VIT-NAS construct led to a two-fold increase in zinc in wholemeal flour, to ∼50 µg g-1. Total iron was not significantly increased, but redistribution within the grain resulted in a three-fold increase in iron in highly pure, roller-milled white flour, to ∼25 µg g-1. Interestingly, expression of OsNAS2 partially restored iron translocation to the aleurone, which is iron depleted in grain overexpressing TaVIT2 alone. A greater than three-fold increase in the level of the natural plant metal chelator nicotianamine in the grain of VIT-NAS lines corresponded with improved iron and zinc bioaccessibility in white flour. The growth of VIT-NAS plants in the greenhouse was indistinguishable from untransformed controls. Our results provide insights into mineral translocation and distribution in wheat grain and demonstrate that the individual and combined effects of the two transgenes can enhance the nutritional quality of wheat beyond what is possible by conventional breeding.

Biofortification—Present Scenario, Possibilities and Challenges: A Scientometric Approach

Biofortification refers to the process by which food crops are improved by the application of biotechnology, conventional plant breeding, and agronomic practices to increase the bioavailability of their nutritious components to human consumers. The biofortification of staple crops is a long-term, sustainable solution to address nutritional inadequacies. Thus, it is a practical and cost-effective way to provide micronutrients to communities that have limited access to various meals and other micronutrient therapies. Existing therapies, such as supplementation and industrial food fortification, which are insufficient to eliminate micronutrient deficiencies on their own, are complemented by biofortification. However, biofortification offers two substantial competitive advantages: the capacity to reach underserved rural communities and long-term cost-effectiveness. Biofortified crops can also be used to target rural populations with limited access to various dietary options or other micronutrient therapies. Hence, an attempt is made herein to provide an overview of the biofortification literature by employing scientometric and network analysis tools to examine records extracted from the Scopus database that were published between 2010 and 2021. This study investigates the most influential authors and journals, top-contributing institutions and countries, variations across publication years, co-occurrence analysis of keywords, and bibliographic coupling of sources. The results obtained through this study describe the real impact of the research published to date and its usage.

Iron and zinc micronutrients and soil inoculation of Trichoderma harzianum enhance wheat grain quality and yield

Malnutrition is mainly caused by iron and zinc micronutrient deficiencies affecting about half of the world's population across the globe. Biofortification of staple crops is the right approach to overcome malnutrition and enhance nutrient contents in the daily food of humans. This study aimed to evaluate the role of foliar application of iron and zinc in Trichoderma harzianum treated soil on various growth characteristics, quality, and yield of wheat varieties. Plants were examined in the absence/presence of T. harzianum, and iron and zinc micronutrients in both optimal and high-stress conditions. Although the symbiotic association of T. harzianum and common wheat is utilized as an effective approach for wheat improvement because of the dynamic growth promoting the ability of the fungus, this association was found tremendously effective in the presence of foliar feeding of micronutrients for the enhancement of various growth parameters and quality of wheat. The utilization of this approach positively increased various growth parameters including spike length, grain mass, biomass, harvest index, and photosynthetic pigments. The beneficial role of T. harzianum in combination with zinc and iron in stimulating plant growth and its positive impact on the intensities of high molecular weight glutenin subunits (HMW-GS) alleles make it an interesting approach for application in eco-friendly agricultural systems. Further, this study suggests a possible alternative way that does not merely enhances the wheat yield but also its quality through proper biofortification of iron and zinc to fulfill the daily needs of micronutrients in staple food.

A randomized trial of iron- and zinc-biofortified pearl millet-based complementary feeding in children aged 12 to 18 months living in urban slums

Biofortification of staple crops with higher levels of micronutrients via traditional breeding methods is a sustainable strategy and can possibly complement fortification and other interventions to target micronutrient deficiencies in low resource settings, particularly among vulnerable populations such as children. We aimed to determine if iron- and zinc-biofortified pearl millet (FeZnPM, Dhanashakti, ICTP-8203Fe)-based complementary feeding improves nutritional status, including iron biomarkers and growth, in children living in urban slums of Mumbai. We conducted a randomized controlled trial of FeZnPM among 223 children aged 12-18 months who were not severely anemic at baseline (hemoglobin ≥9.0g/dL). Children were randomized to receive either FeZnPM or conventional non-biofortified pearl millet (CPM) daily for 9 months. Iron status (hemoglobin, serum ferritin), plasma zinc, and anthropometric indicators (length, weight, mid-upper arm circumference, triceps and subscapular skinfolds) were evaluated at enrollment and throughout the trial. World Health Organization (WHO) anthropometric z-scores were calculated using WHO growth standards. Primary outcomes were hemoglobin and serum ferritin concentrations, and growth, defined as WHO z-scores. An intent to treat approach was used for analyses. We used the Hodges-Lehmann-Sen test to assess the change in primary outcomes between baseline and the last visit and report corresponding 95% confidence intervals. At baseline, 67.7% of children were anemic (hemoglobin <11.0g/dL) and 59.6% were iron deficient (serum ferritin <12.0μg/L). FeZnPM did not significantly increase iron biomarkers or improve growth, compared to CPM. In subgroup analyses, FeZnPM improved hemoglobin concentrations in male children, and in children with iron deficiency or iron depletion (serum ferritin <25.0μg/L) at baseline, relative to CPM. Daily consumption of FeZnPM-based complementary foods did not significantly impact iron and zinc status or growth in children living in Mumbai's urban slums. However, the intervention significantly improved hemoglobin concentrations among male children and among individuals who were iron-deficient or iron-depleted at baseline. This trial is registered with Clinicaltrials.gov (ID: NCT02233764), and Clinical Trials Registry of India (ID: REF/2014/10/007731).

Screening Ca concentration in staple food crops with energy dispersive x-ray fluorescence (EDXRF)

Background and aimsCalcium deficiency is evident in populations worldwide and combating this could be addressed with the biofortification of staple crops. Consequently, identification of Ca concentration in breeding trials would be essential. Here we report the use of energy dispersive x-ray fluorescence (EDXRF) for the rapid screening of Ca concentration in seed samples.MethodsGrain samples of rice, wheat, pearl millet, bean, maize, and cowpea were provided from biofortification breeding programs and analysed with inductively coupled plasma – mass spectrometry (ICP-MS) to determine the reference Ca concentration. A set of samples were used to develop a Ca EDXRF calibration for each crop and another set of samples to validate the method.ResultsThe EDXRF results were comparable to the reference ICP-MS analysis with an average difference of < ± 5 mg kg-1 for all crops and RSD for duplicate analysis < 10% for all crops.ConclusionsEDXRF is suitable for the rapid analysis of Ca in bean, cowpea, wheat, pearl millet, maize and rice samples.

Micronutrients enriched foods: algal resources for biological products and bio-fortification of staple crops

Micronutrients enriched foods: algal resources for biological products and bio-fortification of staple crops

Transcriptional Regulation of Genes Involved in Zinc Uptake, Sequestration and Redistribution Following Foliar Zinc Application to Medicago sativa.

Zinc (Zn) is an essential micronutrient for plants and animals, and Zn deficiency is a widespread problem for agricultural production. Although many studies have been performed on biofortification of staple crops with Zn, few studies have focused on forages. Here, the molecular mechanisms of Zn transport in alfalfa (Medicago sativa L.) were investigated following foliar Zn applications. Zinc uptake and redistribution between shoot and root were determined following application of six Zn doses to leaves. Twelve putative genes encoding proteins involved in Zn transport (MsZIP1-7, MsZIF1, MsMTP1, MsYSL1, MsHMA4, and MsNAS1) were identified and changes in their expression following Zn application were quantified using newly designed RT-qPCR assays. These assays are the first designed specifically for alfalfa and resulted in being more efficient than the ones already available for Medicago truncatula (i.e., MtZIP1-7 and MtMTP1). Shoot and root Zn concentration was increased following foliar Zn applications ≥ 0.1 mg plant−1. Increased expression of MsZIP2, MsHMA4, and MsNAS1 in shoots, and of MsZIP2 and MsHMA4 in roots was observed with the largest Zn dose (10 mg Zn plant−1). By contrast, MsZIP3 was downregulated in shoots at Zn doses ≥ 0.1 mg plant−1. Three functional gene modules, involved in Zn uptake by cells, vacuolar Zn sequestration, and Zn redistribution within the plant, were identified. These results will inform genetic engineering strategies aimed at increasing the efficiency of crop Zn biofortification.

Is There a Carcinogenic Risk Attached to Vitamin B12 Deficient Diets and What Should We Do About It? Reviewing the Facts.

The number of individuals partaking in veganism has increased sharply in the last decade. Therefore, it is critical to look at the implications of vegan diets for public health. Although there are multiple health benefits of a vegan diet, studies have also linked the diet with deficiencies in various micronutrients. This study focuses on vitamin B12, because of its critical role in DNA synthesis and methylation. In light of these connections, a critical review of recent scientific literature is conducted to understand the effects of a B12 deficient diet on the genome and epigenome, and whether it can give rise to cancer. It is observed that a B12 deficiency leads to increased uracil misincorporation, leading to impaired DNA synthesis and genomic instability. The deficiency also leads to global hypomethylation of DNA, a hallmark of early carcinogenesis. The findings of this study highlight the need for increased awareness among vegans to ensure adequate B12 intake through supplementation or consumption of fortified products as a preventative measure. Additionally, the biofortification of staple crops and an improved version of fermented products with increased B12 content can be developed when inadequate intake seems otherwise inevitable.

New Uses for Traditional Crops: The Case of Barley Biofortification

Barley (Hordeum vulgare) is one of the oldest domesticated crops used for both human and animal feed. Over the years however, its role in human diet has been very limited and replaced by the broad use of wheat products. Nowadays, micronutrient deficiency, also known as hidden hunger, is one of the major challenges to human health worldwide. Biofortification of staple crops has been broadly accepted as the best strategy to overcome these limitations. Studies on the nutritional value of barley have proven its multiple benefits on human health and drove new attention towards the cultivation under the light of new food purposes. Biofortification of barley is approached through agronomic practices, conventional breeding, and/or the use of biotechnological tools and research results show that barley can be a promising crop for the emergence of novel food products with a significant impact on human nutrition.

Biofortified Crops for Combating Hidden Hunger in South Africa: Availability, Acceptability, Micronutrient Retention and Bioavailability.

In many poorer parts of the world, biofortification is a strategy that increases the concentration of target nutrients in staple food crops, mainly by genetic manipulation, to alleviate prevalent nutrient deficiencies. We reviewed the (i) prevalence of vitamin A, iron (Fe) and zinc (Zn) deficiencies; (ii) availability of vitamin A, iron and Zn biofortified crops, and their acceptability in South Africa. The incidence of vitamin A and iron deficiency among children below five years old is 43.6% and 11%, respectively, while the risk of Zn deficiency is 45.3% among children aged 1 to 9 years. Despite several strategies being implemented to address the problem, including supplementation and commercial fortification, the prevalence of micronutrient deficiencies is still high. Biofortification has resulted in the large-scale availability of βcarotene-rich orange-fleshed sweet potatoes (OFSP), while provitamin A biofortified maize and Zn and/or iron biofortified common beans are at development stages. Agronomic biofortification is being investigated to enhance yields and concentrations of target nutrients in crops grown in agriculturally marginal environments. The consumer acceptability of OFSP and provitamin A biofortified maize were higher among children compared to adults. Accelerating the development of other biofortified staple crops to increase their availability, especially to the target population groups, is essential. Nutrition education should be integrated with community health programmes to improve the consumption of the biofortified crops, coupled with further research to develop suitable recipes/formulations for biofortified foods.

Investigating seed mineral composition in Korean landrace maize (Zea mays L.) and its kernel texture specificity

Mineral malnutrition affects billions of people all over the world and biofortification of staple crops provides a potential way to alleviate dietary mineral deficiencies. For example, nutritional quality is an important breeding target for fresh waxy maize (Zea mays L.), which is widely consumed in Asian countries. Successful improvement of mineral composition will require comprehensive profiling of the mineral composition of maize varieties and an understanding of the capacity for maize grains to accumulate minerals. Here, using inductively coupled plasma absorption emission spectrometry, we quantified 12 minerals from the seeds of 47 maize varieties, including 25 Korean landraces. We also compared the mineral contents in varieties with different seed starch profiles: waxy maize (which contains 100% amylopectin), dent maize (roughly 75% amylopectin and 25% amylose), and flint maize (similar to dent maize). The amounts of potassium, phosphorus, and sulfur were correlated with seed texture, waxy maize having higher amounts of phosphorus and potassium than dent maize and lower amounts of sulfur than flint maize or dent maize. In addition, a positive relationship was detected between the amount of phosphorus and that of potassium, magnesium, and manganese. These results provide information on maize seed mineral composition and indicate that it could be affected by starch composition. Furthermore, the landraces that exhibit high mineral contents could be used as germplasm materials for breeding programs aimed at producing biofortified maize cultivars.

Determination of carotenoids in sweet potato (Ipomoea batatas L., Lam) tubers: Implications for accurate provitamin A determination in staple sturdy tuber crops

Vitamin A deficiency (VAD) is a global health problem, which despite significant financial investments and initiatives has not been eradicated. Biofortification of staple crops with β-carotene (provitamin A) in Low Medium Income Countries (LMICs) is the approach advocated and adopted by the WHO and HarvestPlus programme. The accurate determination of β-carotene is key to the assessment of outputs from these activities. In the present study, HPLC-PDA analysis displayed superior resolving power, separating and identifying 23 carotenoids in the orange sweet potato (Ipomoea batatas) variety used, including only eight carotenoids with provitamin A properties. Additionally, the results evidently displayed that the use of lyophilised material facilitated the extraction of twice the amount of pigments compared to fresh material, which impacts the precise calculation of the provitamin A content. These results highlight that yellow to orange starchy edible crops produce a wide array of carotenoids in addition to β-carotene. Biosynthetically it is clear from the intermediates and products accumulating that the β-branch of the carotenoid pathway persists in sweet potato tuber material. Collectively, the data also have implications with respect to the determination and biosynthesis of provitamin A among staple crops for developing countries.

Meta-analysis of grain iron and zinc associated QTLs identified hotspot chromosomal regions and positional candidate genes for breeding biofortified rice

Biofortification of staple crops with essential micronutrients is the sustainable way to overcome the hidden hunger. A large number of quantitative trait loci (QTL) linked with grain micronutrient contents have been reported in different mapping studies. Identification of consistent QTLs across diverse genetic backgrounds is useful for candidate gene analysis and marker assisted selection of target traits. In this study, an up to date meta-analysis of grain iron and zinc associated QTLs was performed and 48 meta-QTLs (MQTLs) distributed across 12 rice chromosomes were identified. The 95% confidence intervals of identified genomic regions were significantly narrower than the average of their corresponding original QTLs. A total of 9308 genes/transcripts physically located within or near MQTL regions were retrieved and through prioritization of candidate genes (CGs) 663 non-redundant iron and zinc CGs were selected and studied in detailed. Several functionally characterized iron and zinc homoeostasis related genes e.g OsATM3, OsDMAS1, OsFRO2, OsNAS1-3, OsVIT2, OsYSL16, OsZIP3 and OsZIP7 were also included in our MQTL analysis. More than 64% genes were enriched with zinc and iron binding gene ontology terms and were involved in oxidation reduction process, carbohydrate metabolic process, regulation of transcription, trans-membrane transport, response to oxidative stress, cell redox homeostasis and proteolysis etc. In-silico transcriptomic analysis of rice identified 260 CGs which were regulated in response to iron and zinc stresses. We also identified at least 37 genes which were differentially expressed under both stress conditions and majority of these have not been studied in detailed before. Our results strongly indicate that majority of the MQTLs identified in this study are hotspots for grain iron and zinc concentration and are worth of intensive functional studies in near future.