Biofortification with Iron and Zinc Improves Nutritional and Nutraceutical Properties of Common Wheat Flour and Bread

Biofortification of Plant- and Animal-Based Foods in Limiting the Problem of Microelement Deficiencies-A Narrative Review

With a burgeoning global population, meeting the demand for increased food production presents challenges, particularly concerning mineral deficiencies in diets. Micronutrient shortages like iron, iodine, zinc, selenium, and magnesium carry severe health implications, especially in developing nations. Biofortification of plants and plant products emerges as a promising remedy to enhance micronutrient levels in food. Utilizing agronomic biofortification, conventional plant breeding, and genetic engineering yields raw materials with heightened micronutrient contents and improved bioavailability. A similar strategy extends to animal-derived foods by fortifying eggs, meat, and dairy products with micronutrients. Employing "dual" biofortification, utilizing previously enriched plant materials as a micronutrient source for livestock, proves an innovative solution. Amid biofortification research, conducting in vitro and in vivo experiments is essential to assess the bioactivity of micronutrients from enriched materials, emphasizing digestibility, bioavailability, and safety. Mineral deficiencies in human diets present a significant health challenge. Biofortification of plants and animal products emerges as a promising approach to alleviate micronutrient deficiencies, necessitating further research into the utilization of biofortified raw materials in the human diet, with a focus on bioavailability, digestibility, and safety.

Antioxidant and Hypoglycemic Potential of Phytogenic Selenium Nanoparticle- and Light Regime-Mediated In Vitro Caralluma tuberculata Callus Culture Extract

In vitro plant cultures have emerged as a viable source, holding auspicious reservoirs for medicinal applications. This study aims to delineate the antioxidant and hypoglycemic potential of phytosynthesized selenium nanoparticle (SeNP)- and light stress-mediated in vitro callus cultures of Caralluma tuberculata extract. The morphophysicochemical characteristics of biogenic SeNPs were assessed through a combination of analytical techniques, including UV-visible spectrophotometry, scanning electron microscopy, energy-dispersive X-rays, Fourier transform infrared spectrometry, and zeta potential spectroscopy. The antioxidative potential of the callus extract 200 and 800 μg/mL concentrations was assessed through various tests and exhibited pronounced scavenging potential in reducing power (26.29%), ABTS + scavenging (42.51%), hydrogen peroxide inhibition (37.26%), hydroxyl radical scavenging (40.23%), and phosphomolybdate (71.66%), respectively. To inspect the hypoglycemic capacity of the callus extract, various assays consistently demonstrated a dosage-dependent relationship, with higher concentrations of the callus extract exerting a potent inhibitory impact on the catalytic sites of the alpha-amylase (78.24%), alpha-glucosidase (71.55%), antisucrase (59.24%), and antilipase (74.26%) enzyme activities, glucose uptake by yeast cells at 5, 10, and 25 mmol/L glucose solution (72.18, 60.58 and 69.33%), and glucose adsorption capacity at 5, 10, and 25 mmol/L glucose solution (74.37, 83.55, and 86.49%), respectively. The findings of this study propose selenium NPs and light-stress-mediated in vitro callus cultures of C. tuberculata potentially operating as competitive inhibitors. The outcomes of the study were exceptional and hold promising implications for future medicinal applications.

Alleviation potential of green-synthesized selenium nanoparticles for cadmium stress in Solanum lycopersicum L: modulation of secondary metabolites and physiochemical attributes

KEY MESSAGE

Selenium nanoparticles reduce cadmium absorption in tomato roots, mitigating heavy metal effects. SeNPs can efficiently help to enhance growth, yield, and biomolecule markers in cadmium-stressed tomato plants. In the present study, the effects of selenium nanoparticles (SeNPs) were investigated on the tomato plants grown in cadmium-contaminated soil. Nanoparticles were synthesized using water extract of Nigella sativa and were characterized for their size and shape. Two application methods (foliar spray and soil drench) with nanoparticle concentrations of 0, 100, and 300 mg/L were used to observe their effects on cadmium-stressed plants. Growth, yield, biochemical, and stress parameters were studied. Results showed that SeNPs positively affected plant growth, mitigating the negative effects of cadmium stress. Shoot length (SL), root length (RL), number of branches (NB), number of leaves per plant (NL), and leaf area (LA) were significantly reduced by cadmium stress but enhanced by 45, 51, 506, 208, and 82%, respectively, by soil drench treatment of SeNPs. Similarly, SeNPs increased the fruit yield (> 100%) and fruit weight (> 100%), and decreased the days to fruit initiation in tomato plants. Pigments were also positively affected by the SeNPs, particularly in foliar treatment. Lycopene content was also enhanced by the addition of NPs (75%). Furthermore, the addition of SeNPs improved the ascorbic acid, protein, phenolic, flavonoid, and proline contents of the tomato plants under cadmium stress, whereas stress enzymes also showed enhanced activities under cadmium stress. It is concluded from the present study that the addition of selenium nanoparticles enhanced the growth and yield of Cd-stressed plants by reducing the absorption of cadmium and increasing the stress management of plants.

Dietary Zn deficiency, the current situation and potential solutions

Zinc (Zn) deficiency is a worldwide problem, and this review presents an overview of the magnitude of Zn deficiency with a particular emphasis on present global challenges, current recommendations for Zn intake, and factors that affect dietary requirements. The challenges of monitoring Zn status are clarified together with the discussion of relevant Zn bioaccessibility and bioavailability issues. Modern lifestyle factors that may exacerbate Zn deficiency and new strategies of reducing its effects are presented. Biofortification, as a potentially useful strategy for improving Zn status in sensitive populations, is discussed. The review proposes potential actions that could deliver promising results both in terms of monitoring dietary and physiological Zn status as well as in alleviating dietary Zn deficiency in affected populations.

A Recent Update on the Impact of Nano-Selenium on Plant Growth, Metabolism, and Stress Tolerance

Selenium (Se) is a microelement that plays an important nutrient role by influencing various physiological and biochemical traits in plants. It has been shown to stimulate plant metabolism, enhancing secondary metabolites and lowering abiotic and biotic stress in plants. Globally, the enormous applications of nanotechnology in the food and agricultural sectors have vastly expanded. Nanoselenium is more active than bulk materials, and various routes of synthesis of Se nanoparticles (Se-NPs) have been reported in which green synthesis using plants is more attractive due to a reduction in ecological issues and an increase in biological activities. The Se-NP-based biofortification is more significant because it increases plant stress tolerance and positively impacts their metabolism. Se-NPs can enhance plant resistance to various oxidative stresses, promote growth, enhance soil nutrient status, enhance plant antioxidant levels, and participate in the transpiration process. Additionally, they use a readily available, biodegradable reducing agent and are ecologically friendly. This review concentrates on notable information on the different modes of Se-NPs' synthesis and characterization, their applications in plant growth, yield, and stress tolerance, and their influence on the metabolic process.

Effect of Milling on Nutritional Components in Common and Zinc-Biofortified Wheat

Biofortification is one of the most successful approaches to enhance the level of micronutrients in wheat. In the present study, wheats with zinc biofortification (foliar fertilization and breeding strategies) were milled into five components (whole flour, break flour, reduction flour, fine bran, and coarse bran) and their mineral content and nutritional components were evaluated. The results revealed that biofortification greatly increased the Zn concentration (by 30.58%-30.86%) and soluble Zn content (by 28.57%-42.86%) of whole flour after digestion. This improvement is mainly in break flour, reduction flour, and fine bran. Meanwhile, the contents of macronutrients including ash, lipids, and proteins and micronutrients containing iron, calcium, and vitamins (B₁, B₆, and B₉) increased after biofortification. In addition, there was a decline in the concentrations of vitamins B₂ and B₅. Although dietary fibers and starch are the major carbohydrates, total dietary fiber exhibited a declining trend in coarse bran, and starch exhibited a rising trend in break and reduction flour. There was a decrease in the molar ratio of phytates: zinc did not promote a significant improvement in zinc bioaccessibility. These results can be useful for generating wheat varieties rich in micronutrients as well as having better nutritional traits.

Probiotics Enhance Cereal Yield and Quality and Modify Agrochemical Soil Properties

The aim of this study was to determine the influence of microbial biostimulants on wheat and oat growth, grain yield, and grain quality and to evaluate the influence of these probiotics on some soil agrochemical traits in the open field. Active concentrations of ProbioHumus and NaturGel and their mixtures were selected under laboratory conditions using winter wheat as a reference plant. Probiotics had a biostimulating effect on the development of the underground and aboveground part of winter wheat when 2 µL/g was used for seed priming and 2 mL/100 mL for seedling spraying. Under field conditions, after treatment of soil (2 L/ha), wheat and oat seeds (2 L/t), and plants (2 L/ha) with ProbioHumus and NaturGel, it was found that the yield of the studied cereals increased, on average, by 0.50 t/ha to 1.09 t/ha. ProbioHumus promoted protein accumulation in the investigated cereal grains. The level of microelements in wheat and oat grains increased after treatment of plants with NaturGel. Probiotics improved soil agrochemical properties, such as total and nitrate nitrogen, total and available phosphorus, organic carbon, humic acid, and humus content. In conclusion, plant probiotics can be used as an ecological alternative for growing cereals and improving the agrochemical properties of the soil.

Genetic biofortification of wheat with zinc: Opportunities to fine-tune zinc uptake, transport and grain loading

Zinc (Zn) is an important micronutrient in the human body, and health complications associated with insufficient dietary intake of Zn can be overcome by increasing the bioavailable concentrations in edible parts of crops (biofortification). Wheat (Triticum aestivum L) is the most consumed cereal crop in the world; therefore, it is an excellent target for Zn biofortification programs. Knowledge of the physiological and molecular processes that regulate Zn concentration in the wheat grain is restricted, inhibiting the success of genetic Zn biofortification programs. This review helps break this nexus by advancing understanding of those processes, including speciation regulated uptake, root to shoot transport, remobilisation, grain loading and distribution of Zn in wheat grain. Furthermore, new insights to genetic Zn biofortification of wheat are discussed, and where data are limited, we draw upon information for other cereals and Fe distribution. We identify the loading and distribution of Zn in grain as major bottlenecks for biofortification, recognising anatomical barriers in the vascular region at the base of the grain, and physiological and molecular restrictions localised in the crease region as major limitations. Movement of Zn from the endosperm cavity into the modified aleurone, aleurone and then to the endosperm is mainly regulated by ZIP and YSL transporters. Zn complexation with phytic acid in the aleurone limits Zn mobility into the endosperm. These insights, together with synchrotron-X-ray-fluorescence microscopy, support the hypothesis that a focus on the mechanisms of Zn loading into the grain will provide new opportunities for Zn biofortification of wheat.

Influence of Drought and Salt Stress on Durum Wheat Grain Quality and Composition: A Review

Durum wheat is a staple crop for the Mediterranean diet because of its adaptability to environmental pressure and for its large use in cereal-based food products, such as pasta and bread, as a source of calories and proteins. Durum wheat whole grains are also highly valued for their peculiar amount of dietary fiber and minerals, as well as bioactive compounds of particular interest for their putative health-beneficial properties, including polyphenols, carotenoids, tocopherols, tocotrienols, and phytosterols. In Mediterranean environments, durum wheat is mostly grown under rainfed conditions, where the crop often experiences environmental stresses, especially water deficit and soil salinity that may induce a hyperosmotic stress. In particular, changes in C and N accumulation due to these abiotic conditions, during grain filling, can influence starch and storage protein amount and composition in durum wheat caryopsis, thus influencing yield and quality traits. Recent advancements regarding the influence of water deficit and salinity stress on durum wheat are critically discussed. In particular, a focus on stress-induced changes in (a) grain protein content and composition in relation to technological and health quality; (b) starch and dietary fiber accumulation and composition; (c) phytochemical composition; (d) health-related grain micronutrient accumulation, such as Fe and Zn.

Concentration and Localization of Fe and Zn in Wheat Grain as Affected by Its Application to Soil and Foliage

Nutritional status of people can be improved by enhancing zinc (Zn) and iron (Fe) content in cereals used as staple mainly in poor resource countries. Zinc and Fe were applied through soil and foliage in a study to biofortify wheat grains. Foliar application of both micronutrients increased the growth and grain vigor as compared to soil application and control. Also, foliar application significantly enhanced Zn and Fe concentration in grain pre-dominantly localized in aleurone layer. Exogeneous application of Fe and Zn was found beneficial for plant growth and enhanced Fe and Zn concentrations in grain, however aleurone layer and embryonic region of the grain showed higher accumulations than that in endosperm. Therefore, understanding of physiological and molecular pathways for uptake and localization of Fe and Zn in wheat grains need to be critically examined to improve their concentration in grain to achieve the biofortification targets.

Direct transfer of zinc between plants is channelled by common mycorrhizal network of arbuscular mycorrhizal fungi and evidenced by changes in expression of zinc transporter genes in fungus and plant

The role that common mycorrhizal networks (CMNs) play in plant-to-plant transfer of zinc (Zn) has not yet been investigated, despite the proved functions of arbuscular mycorrhizal fungi (AMF) in crop Zn acquisition. Here, two autotrophic Medicago truncatula plants were linked by a CMN formed by Rhizophagus irregularis. Plants were grown in vitro in physically separated compartments (Donor-C and Receiver-C) and their connection ensured only by CMN. A symbiosis-defective mutant of M. truncatula was used as control in Receiver-C. Plants in both compartments were grown on Zn-free medium, and only the leaves of the donor plants were Zn fertilized. A direct transfer of Zn was demonstrated from donor leaves to receiver shoots mediated by CMN. Direct transfer of Zn was supported by changes in the expression of fungal genes, RiZRT1 and RiZnT1, and plant gene MtZIP2 in roots and MtNAS1 in roots and shoots of the receiver plants. Moreover, Zn transfer was supported by the change in expression of MtZIP14 gene in AM fungal colonized roots. This work is the first evidence of a direct Zn transfer from a donor to a receiver plant via CMN, and of a triggering of transcriptional regulation of fungal-plant genes involved in Zn transport-related processes.

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.

Glutacetine® Biostimulant Applied on Wheat under Contrasting Field Conditions Improves Grain Number Leading to Better Yield, Upgrades N-Related Traits and Changes Grain Ionome

Wheat is one of the most important cereals for human nutrition, but nitrogen (N) losses during its cultivation cause economic problems and environmental risks. In order to improve N use efficiency (NUE), biostimulants are increasingly used. The present study aimed to evaluate the effects of Glutacetine^®, a biostimulant sprayed at 5 L ha⁻¹ in combination with fertilizers (urea or urea ammonium nitrate (UAN)), on N-related traits, grain yield components, and the grain quality of winter bread wheat grown at three field sites in Normandy (France). Glutacetine^® improved grain yield via a significant increase in the grain number per spike and per m², which also enhanced the thousand grain weight, especially with urea. The total N in grains and the NUE tended to increase in response to Glutacetine^®, irrespective of the site or the form of N fertilizer. Depending on the site, spraying Glutacetine^® can also induce changes in the grain ionome (analyzed by X-ray fluorescence), with a reduction in P content observed (site 2 under urea nutrition) or an increase in Mn content (site 3 under UAN nutrition). These results provide a roadmap for utilizing Glutacetine^® biostimulant to enhance wheat production and flour quality in a temperate climate.

Zinc Enrichment in two Contrasting Genotypes of Triticum aestivum L. Grains: Interactions between Edaphic Conditions and Foliar Fertilizers

This study aimed to assess the implications of Zn enrichment in wheat grains as a function of contrasting genotypes, edaphic conditions and foliar fertilizers. Triticum aestivum L. varieties Roxo and Paiva were grown in four production fields, and sprayed with ZnSO4 (0, 16.20 and 36.40 kg/ha) Zn-EDTA (0, 6.30 and 12.60 kg/ha) and Tecnifol Zinc (0, 3.90 and 7.80 kg/ha). The heterogeneous edaphic conditions of the wheat fields were chemically characterized, it being found that soil properties determine different Zn accumulation in the grains of both genotypes. Foliar spraying enhanced to different extents Zn content in the grains of both genotypes, but the average of enrichment indexes varied among the wheat fields. Zinc mostly accumulated in the embryo and vascular bundle and to a lesser extent in the endosperm. Grain yield and test weight sprayed by ZnSO4 gave the highest values in both genotypes, but the opposite was found for Zn-EDTA. Considering the color parameters, lightness and red-green transitions were found to be a conjunction of genotype characteristics, fertilization types and edaphic conditions prevailing in each field. It is concluded that the index of Zn enrichment in wheat grains is a docket of edaphic conditions, genotype and type of fertilization.

Biostimulant Effects of Glutacetine® and Its Derived Formulations Mixed With N Fertilizer on Post-heading N Uptake and Remobilization, Seed Yield, and Grain Quality in Winter Wheat

Biostimulants could play an important role in agriculture particularly for increasing N fertilizer use efficiency that is essential for maintaining both yield and grain quality in bread wheat, which is a major global crop. In the present study, we examined the effects of mixing urea-ammonium-nitrate fertilizer (UAN) or urea with five new biostimulants containing Glutacetine® or its derivative formulations (VNT1, 2, 3, and 4) on the physiological responses, agronomic traits, and grain quality of winter wheat. A first experiment under greenhouse conditions showed that VNT1, VNT3, and VNT4 significantly increased the seed yield and grain numbers per ear. VNT4 also enhanced total plant nitrogen (N) and total grain N, which induced a higher N Harvest Index (NHI). The higher post-heading N uptake (for VNT1 and VNT4) and the acceleration of senescence speed with all formulations enabled better nutrient remobilization efficiency, especially in terms of N mobilization from roots and straw toward the grain with VNT4. The grain ionome was changed by the formulations with the bioavailability of iron improved with the addition of VNT4, and the phytate concentrations in flour were reduced by VNT1 and VNT4. A second experiment in three contrasting field trials confirmed that VNT4 increased seed yield and N use efficiency. Our investigation reveals the important role of these new formulations in achieving significant increases in seed yield and grain quality.

Zinc in Wheat Grain, Processing, and Food

Improving zinc (Zn) content in wheat and its processed foods is an effective way to solve human Zn deficiency, which can cause a variety of diseases. This article summarizes the works on Zn in wheat grain, wheat processing, and wheat-derived foods. Grain Zn content in wheat was 31.84 mg·kg-1 globally but varied across continents, for example, 25.10 mg·kg-1 in Europe, 29.00 mg·kg-1 in Africa, 33.63 mg·kg-1 in Asia, and 33.91 mg·kg-1 in North America. Grain Zn content in wheat improved from 28.96 to 36.61 mg·kg-1 and that in flour increased from 10.51 to 14.82 mg·kg-1 after Zn fortification. Furthermore, Zn content varied in the different processed components of wheat; that is, Zn content was 12.58 mg·kg-1 in flour, 70.49 mg·kg-1 in shorts, and 86.45 mg·kg-1 in bran. Zinc content was also different in wheat-derived foods, such as 13.65 mg·kg-1 in baked food, 10.65 mg·kg-1 in fried food, and 8.03 mg·kg-1 in cooking food. Therefore, the suitable Zn fortification, appropriate processing, and food type of wheat are important to meet people's Zn requirement through wheat.

Field Inoculation of Bread Wheat with Rhizophagus irregularis under Organic Farming: Variability in Growth Response and Nutritional Uptake of Eleven Old Genotypes and A Modern Variety

Arbuscular mycorrhizal fungi (AMF) promote crop growth and yield by increasing N and P uptake and disease resistance, but the role of field AMF inoculation on the uptake of micronutrients, such as Fe and Zn, and accumulation in plant edible portions is still not clarified. Therefore, we studied the effect of field inoculation with Rhizophagus irregularis in an organic system on 11 old genotypes and a modern variety of bread wheat. Inoculation increased root colonization, root biomass and shoot Zn concentration at early stage and grain Fe concentration at harvest, while it did not modify yield. Genotypes widely varied for shoot Zn concentration at early stage, and for plant height, grain yield, Zn and protein concentration at harvest. Inoculation differentially modified root AMF community of the genotypes Autonomia B, Frassineto and Bologna. A higher abundance of Rhizophagus sp., putatively corresponding to the inoculated isolate, was only proved in Frassineto. The increase of plant growth and grain Zn content in Frassineto is likely linked to the higher R. irregularis abundance. The AMF role in increasing micronutrient uptake in grain was proved. This supports the introduction of inoculation in cereal farming, if the variable response of wheat genotypes to inoculation is considered.

The mycorrhizal pathway of zinc uptake contributes to zinc accumulation in barley and wheat grain

BACKGROUND

Increasing zinc (Zn) concentrations in crops is important for alleviation of human Zn deficiency. Arbuscular mycorrhizal fungi (AMF) contribute to plant Zn uptake, but their contribution to Zn in the edible portion of crops has not yet been investigated. This study aimed to quantify the mycorrhizal pathway of Zn uptake into grain of wheat and barley under varying soil Zn availabilities. Bread wheat (Triticum aestivum) and barley (Hordeum vulgare) were grown in pots with a hyphal compartment containing 65Zn. Plants were inoculated with Rhizophagus irregularis and grown at three soil Zn concentrations. Radioactive Zn in grain and straw was measured and the contribution of AMF to Zn uptake was calculated.

RESULTS

The mycorrhizal pathway of Zn uptake contributed up to 24.3% of total above-ground Zn in wheat, and up to 12.7% of that Zn in barley. The greatest contribution by the mycorrhizal pathway was observed in barley at the lowest Zn addition, and in wheat at the highest one. In addition, grain yield of bread wheat was increased by AMF.

CONCLUSIONS

These results suggest that AMF have a substantial role in uptake of Zn into cereals, and the proportional contribution by the MPU is dependent on plant species, as well as available soil Zn.

Exposure to Weathered and Fresh Nanoparticle and Ionic Zn in Soil Promotes Grain Yield and Modulates Nutrient Acquisition in Wheat ( Triticum aestivum L.)

This study evaluated weathered and fresh ZnO-nanoparticles and Zn-salt effects on nutrient acquisition and redistribution in wheat. Weathered and fresh ZnO-nanoparticles and Zn-salt significantly increased grain yield by 15% and 29%, respectively. Postharvest soil acidification indicated ZnO-nanoparticles dissolved during growth. Zn was significantly bioaccumulated from both Zn types, but with low root-to-shoot bioaccumulation efficiency: 24% and 20% for weathered nanoparticles and salt, and 48% and 30% for fresh nanoparticles and salt. Grain Zn content was increased 186% and 229% by weathered nanoparticles and salt, and 229% and 300% by fresh nanoparticles and salt. Shoot-to-grain translocation efficiency was high: 167% and 177% for weathered nanoparticles and salt, and 209% and 155% for fresh nanoparticles and salt. However, Zincon assay indicated grain Zn does not exist as ions. This study demonstrates that ZnO-nanoparticles and Zn-salt vary in their effects on nutrient acquisition in wheat, with relevance for biofortification of Zn for human nutrition.

Arbuscular mycorrhizal fungi increase grain zinc concentration and modify the expression of root ZIP transporter genes in a modern barley (Hordeum vulgare) cultivar

The positive effects of arbuscular mycorrhizal fungi (AMF) on the zinc (Zn) nutrition of a number of cereal species has been demonstrated, but for Hordeum vulgare (barley), this has been scarcely investigated. Zn is taken up by ZIP transporters in the roots, and several barley ZIP transporter genes are up-regulated under Zn deficient conditions. We grew a modern cultivar of barley (cv. Compass) at five different soil Zn concentrations ranging from no addition through to a toxic concentration. The plants were either inoculated with the AMF Rhizophagus irregularis, or mock-inoculated. At harvest, measurements of biomass, tissue Zn concentration, and expression of ZIP transporter genes were taken. Inoculation of barley with AMF resulted in improved grain and straw Zn concentrations, especially at low soil Zn concentrations, but did not increase the biomass of the plants. Of the five HvZIP genes tested that are up-regulated under low Zn conditions, one gene (HvZIP13) was significantly up-regulated by mycorrhizal colonisation at the lowest Zn treatment. Two other ZIP genes were down-regulated in mycorrhizal plants under low soil Zn. Inoculation with AMF has an effect on ZIP transporter genes in the roots of barley plants. Furthermore, AMF may be more useful for improving quality of barley grain in terms of Zn concentrations, rather than improving yield.