Agronomic Biofortification Research Articles

Nutrient Composition of Arugula Leafy Greens Following Application of Ascorbic Acid Foliar Sprays

Agronomic biofortification of vitamin C is a promising strategy to address vitamin C deficiencies in populations that lack access to diverse and nutritious diets. Different application methods can improve the vitamin C content in various crops; however, foliar application of ascorbic acid (AA) solutions has been under-explored. To determine if spray concentration, number of applications, and day of harvest would affect vitamin C in arugula leafy greens, foliar sprays consisting of 100 ppm and 200 ppm of AA and deionized (DI) water control were applied. Treatment application was initiated during the baby-leaf stage and subjected to a total of three sprays over the course of the experiment, followed by harvest at two days and four days after spraying (DAS). The harvested plants were measured for fresh and dry biomass and analyzed for vitamin C content, mineral composition, chlorophyll levels, and carotenoid content. The results of this study demonstrated a notably elevated total vitamin C concentration (p = 0.0002) and AA content (p = 0.02) in arugula leaves treated with a 200 ppm AA spray following the third application and harvested at 4 DAS. Additionally, the AA application improved the fresh and dry weight of leafy greens but did not exhibit any significant variances regarding the mineral composition of P, K, Ca, Mg, S, B, Zn, Mn, and Fe. Alternatively, AA foliar sprays reduced Cu content in leaves suggesting that AA reduced Cu accumulation in arugula leafy greens. In summary, the findings of this study establish that the foliar application of 200 ppm AA is an effective approach for increasing the vitamin C content in arugula leafy greens while improving the plant’s biomass, mineral composition, and stress responses. These biofortified arugula leafy greens exhibit the potential to offer plant protection against environmental stresses and a more consistent supply of vitamin C to humans upon consumption.

Nanomaterial-Based Biofortification: Potential Benefits and Impacts of Crops.

Nanomaterials (NMs) have shown relevant impacts in crop protection, improvement of yields, and minimizing collateral side effects of fertilizer and pesticides in vegetable and fruit production. The application of NMs to improve biofortification has gained much attention in the last five years, offering a hopeful and optimistic outlook. Thus, we propose comprehensively revising the scientific literature about the use of NMs in the agronomic biofortification of crops and analyzing the beneficial impact of the use of NMs. The results indicated that different species of plants were biofortified with essential elements and macronutrients after the applications of Zn, Fe, Se, nanocomposites, and metalloid NPs. In addition, the physiological performances, antioxidant compounds, and yields were improved with NMs. Using nanofertilizers for the biofortification of crops can be considered a promising method to deliver micronutrients for plants with beneficial impacts on human health, the environment, and agriculture.

Crop Biofortification of Finger Millet Through Agronomic Approaches to Enhance Bioactive Compounds for Human Health and Nutrition

Finger millet (Eleusine coracana L.) is a gluten-free cereal crop widely grown in Africa and Asia, recognized for its rich bioactive compounds and health benefits. It contains high levels of polyphenols, flavonoids, and tannins with potent antioxidant properties, which help neutralize free radicals and reduce oxidative damage. These compounds also have anti-inflammatory effects, potentially lowering the risk of chronic diseases like cancer and cardiovascular diseases. Additionally, finger millet is a valuable source of essential minerals such as iron, zinc, calcium and magnesium, crucial for bone health, cognitive function, and body immune. Its high dietary fiber content aids gastrointestinal health, regulates blood sugar and reduces the risk of type 2 diabetes, obesity and heart disease. Finger millet is particularly high in essential amino acids, making it an excellent protein choice for vegetarians. Agronomic biofortification, which involves adding zinc, calcium, and iron to the soil and leaves of plants can increase the mineral content of the grain. This review investigates different approaches of agronomic biofortification of finger millet and explore the health and nutritional benefits of bioactive components with a focus on their role as a functional diet in the prevention and management of chronic diseases.

Enhancing Animal Nutritional Security Through Biofortification in Forage Crops: A Comprehensive Review

Livestock nutrition is crucial for sustaining the health and productivity of farm animals, which are a cornerstone of the global food supply. Proper nutrition ensures that animals receive the necessary nutrients for essential bodily functions, growth, reproduction and lactation. Tailored, balanced diets that cater to the specific nutritional needs of different livestock species and their developmental stages also boost reproductive performance, leading to higher birth rates and healthier offspring. Conversely, inadequate nutrition can lead to stunted growth, diminished productivity, and increased vulnerability to diseases, ultimately resulting in significant economic losses. Nutritional imbalances among animals, especially in dairy goats and cattle, pose a significant challenge in livestock management. These disorders result from inadequate or imbalanced nutrient intake, leading to a range of metabolic and health issues. Fodders are essential to livestock nutrition, providing a balanced diet that supports overall animal health, growth and productivity. They are primary sources of energy, with grasses and cereals supplying carbohydrates needed for maintenance and production activities. Leguminous fodders like alfalfa and clover are rich in protein and crucial for muscle development, milk production and growth. Additionally, green fodders offer vital vitamins (A, D, E, K) and minerals such as calcium and phosphorus, which are necessary for various metabolic functions. The high fibre content in fodders aids in proper digestion and prevents digestive disorders. Overall, the review highlights the impact of various nutrient deficiencies on livestock, including the effects of anti-nutritional factors and the mechanisms of nitrate, oxalate and prussic acid toxicity in animals. It underscores the importance of agronomic bio fortification as a promising strategy to enhance the nutritional quality of fodder crops, thereby improving animal health and welfare, while also contributing to food security and sustainable agriculture.

Short‐Term Benefits of Tillage and Agronomic Biofortification for Soybean–Wheat Cropping in Central India

ABSTRACTIn a changing climate, conservation tillage and agronomic biofortification are essential for enhancing crop yield, nutritional security, carbon stocks, and soil quality. Consequently, a field study was conducted in central India to assess the short‐term (4 years) effects of crop establishment techniques (CETs) and agronomic biofortification methods (ABMs) on soil health indicators, grain yield, and quality in the soybean–wheat cropping system. The experiment followed a split‐plot design with two CETs in the main plots (permanent broad bed furrow, PBBF, and conventional tillage, CT) and eight ABMs, each with three replications. The results indicated that PBBF and ABMs (seed inoculation with the microbial strains MDSR 14 + MDSR 34, and soil and foliar application of Zn+Fe) improved soil carbon stock (by 49.6% and 52.4%), available nitrogen, phosphorus, potassium, available Zn (by 30.0%), and Fe (by 21.9%) after the fourth year of the study. Similarly, PBBF and microbial inoculation increased soil enzyme activities (dehydrogenase, acid phosphatase, and β‐glucosidase), substrate‐induced respiration, and microbial biomass carbon content. As a result, a higher soybean equivalent yield (5.59% higher in PBBF and 14.2% higher with foliar spray of Zn+Fe) and seed quality attributes (crude protein yield, grain Zn, and Fe) were observed in PBBF and the foliar spray of Zn and Fe treatments compared to CT and control, respectively. Overall, adopting the short‐term PBBF system, microbial inoculation, and soil and foliar application of Zn and Fe improved rhizosphere biochemical properties, yield, and seed quality in the soybean–wheat system.

Effect of Agronomic Biofortification of Zinc and Iron on Plant Height and Seed Yield of Chickpea (Cicer arietinum L.) Varieties

The present field experiment was conducted to study the effect of agronomic biofortification of zinc and iron on chickpea during Rabi season of 2021-22 and 2022-23 at the instructional farm, College of Agriculture, Jodhpur. The field experiment was laid out in split plot design comprised two varieties of chickpea (‘GNG-2144’ and ‘GNG-2171’) and three levels of iron fortification treatment including control (F0), 20 kg FeSO4 (SA) + 0.5 % FeSO4 (F1) and 25 kg FeSO4 (SA) + 0.5 % FeSO4 (F3) in the main plot and four-levels of zinc fortification viz. control (Z0), ZSB (SI) + 15 kg ZnSO4 (SA) + 0.5 % ZnSO4 (Z1), ZSB (SI) + 20 kg ZnSO4 (SA) + 0.5 % ZnSO4 (Z2) and ZSB (SI) + 25 kg ZnSO4 (SA) + 0.5 % ZnSO4 (Z3) in sub-plot. These three experimental variables make twenty-four treatment combinations were taken as experimental factors to study their effect on biofortification in chickpea. The results revealed that variety GNG-2144 recorded higher plant height and higher seed yield over variety GNG-2171. Among Iron levels treatment 25 kg FeSO4 (SA) + 0.5 % FeSO4 (F3) significantly recorded higher seed yield as compare to 20 kg FeSO4 (SA) + 0.5 % FeSO4 (F1). Moreover, Zinc fortification treatment ZSB (SI) + 25 kg ZnSO4 (SA) + 0.5 % ZnSO4 (Z3) was found significantly superior over the treatment ZSB (SI) + 15 kg ZnSO4 (SA) + 0.5 % ZnSO4 (Z1) and at par with ZSB (SI) + 20 kg ZnSO4 (SA) + 0.5 % ZnSO4 (Z2).

Agronomic biofortification of tomatoes with iron enhances growth, yield and quality

ABSTRACT Agronomic biofortification with iron (Fe) in tomatoes has emerged as a promising strategy to combat global iron deficiency. Iron is essential for human health and plays a critical role in the growth and development of crops. This study aimed to determine the optimal dose of Fe for tomato biofortification and assess its impact on its growth, yield and quality attributes, particularly the fruit’s Fe content. A greenhouse experiment was conducted using tomato hybrids Sandal and Sahel, applying Fe foliar treatments at concentrations of 0, 1, 3, 6 and 9 mM Fe per plant. The results demonstrated that foliar application of 6 mM Fe significantly enhanced the tomato’s growth, yield and quality, while markedly increasing the fruit’s Fe content to 30.07 and 34.1 mg kg−1 in Sandal and Sahel hybrids, respectively. These values were substantially higher than those of the control treatment with Fe contents of 14.77 and 15.0 mg kg−1, respectively. However, higher doses of Fe (> 6 mM Fe per plant) showed adverse effects on growth, yield, and quality. Foliar application of iron proved an effective and economical solution, readily integrated into commercial tomato production, offering farmers a practical method to produce Fe-biofortified tomatoes and combat iron deficiency-linked malnutrition.

Foliar iodine application: a strategy for tomato biofortification and yield optimization

Iodine (I) is a beneficial micronutrient for crop plants and essential for human health, yet approximately two billion people worldwide suffer from I deficiency, resulting in significant health issues. Agricultural soils often lack sufficient I, resulting in crops with low I content. However, tomatoes have shown potential to accumulate I when supplemented externally, making them an ideal candidate for I biofortification, particularly as an alternative to iodized salt for individuals on low-sodium diets. This two-year greenhouse pot experiment evaluated the effectiveness of foliar application of potassium iodide (KI) in biofortifying two commercial tomato hybrids. Different concentrations of I (0, 1, 3, 6, and 9 mM/plant) were applied as foliar treatments to assess their effects on physiological parameters, yield attributes, and quality traits, especially I enrichment in tomato fruit. The results demonstrated that foliar application of KI significantly increased fruit I contents at concentrations that also promoted overall plant growth and development. These findings underscored the efficient translocation of I through the phloem in tomatoes. I enrichment in tomato fruits ranged up to 5.27 mg/kg, exceeding the recommended daily allowance (RDA) of 150 μg/day. Even lower doses of 1–3 mM KI were effective in achieving significant I enrichment suitable for biofortification programs. In conclusion, tomato emerged as an excellent candidate for agronomic biofortification with I due to the practicality, and affordability of foliar application. The study highlights the potential of foliar I application as a feasible strategy for addressing global I deficiency, emphasizing its suitability for widespread adoption by farmers.

Biofortification in garden peas through multi-micronutrient formulations

Soil micronutrient deficiencies lead to crops with low essential element concentrations, affecting human health through micronutrient malnutrition. Effective practices, like foliar nutrient application, improve crop quality and reduce malnutrition. The garden pea (Pisum sativum L. var. hortense) is cultivated worldwide for its nutritional value and such nutrient-rich crops, through agronomic biofortification, offer a sustainable solution to global health issues by addressing micronutrient deficiencies. Four liquid micronutrient formulations [Treatment 1 (T1), Treatment 2 (T2), Treatment 3 (T3), and Treatment 4 (T4)] were prepared using either water or vermiwash as a carrier, with variations that included the presence or absence of plant growth regulators (GA3 + NAA)] and evaluated along with commercially available formulations [Arka Vegetable Special (T5) and ProKissan (T6)]. Micronutrient formulations, particularly T3, demonstrated notable effects on various parameters, including plant height, biomass, root characteristics, pod weight, and micronutrient contents in seeds of garden pea var. Kashi Nandini. T3 significantly outperformed other formulations in promoting plant growth, resulting in higher values for plant height, biomass, branches per plant, nodule mass, root biomass, surface area, volume, and density. Yield parameters such as pod length, weight, number of pods, and seeds per pod were also positively influenced by micronutrient treatments, with T3 leading to the highest overall yield, with a 24.09 % increase per plant and a 13.39 % increase per hectare compared to the control. Additionally, foliar application of micronutrients increased the concentration of copper, zinc, iron, and manganese in seeds, positively impacting seed quality. Quality parameters, including total soluble solids, protein, total phenol, and total flavonoid contents, were significantly improved by micronutrient treatments, with T3 showing the most favorable outcomes. Texture analysis indicated that peas treated with T3 had lower firmness values, suggesting maintained tenderness and sweetness. Correlation analysis revealed strong positive associations between various growth parameters, yield traits, and micronutrient contents. Overall, foliar micronutrient application proved to be a valuable biofortification strategy for enhancing the performance and quality of garden peas.

Soil zinc surveillance frameworks can inform human nutrition studies: opportunities in India

Mineral micronutrient deficiencies are widespread in global food systems and can affect plant growth, crop quality, and human and livestock health. The mapping of soils and soil properties linked to micronutrient supply in food systems is now enabling us to better understand the linkages between soil health and function and its relationship with food quality and human health. Zinc (Zn) deficiencies in Indian soils are of particular concern in the context of crop yields and food quality. This current review aims to understand the data landscapes on soil Zn and related soil properties in India, with a particular focus on three states: Uttar Pradesh (UP), Bihar, and Odisha. The scope of the review is to identify and describe data sets from national and state-wide programmes and research experiments in which soil Zn has been reported, which could be used to provide a framework for integrated surveys and would combine wider agriculture, food systems, nutrition, and public health sectors. The largest data set on soil Zn was collected under a soil health management (SHM) programme, during which the Indian government analysed more than 30 million soil samples for Zn concentration (mg/kg) from 2015 to 2019. This study showed that 39% of Indian soils are considered Zn deficient for crop production (i.e., based on a threshold of <0.6 mg/kg); soil Zn deficiency varied from 2% to 67% across different Indian states. From this survey, soil Zn deficiency was 29%, 67%, and 48% in UP, Bihar, and Odisha, respectively. Individual data points are available for re-use at the Government of India soil health card website (https://www.soilhealth.dac.gov.in/). In addition, the All India Coordinated Research Project on Micro and Secondary Nutrients and Pollutant Elements in Soils and Plants (AICRP-MSPE) programme under the Indian Council of Agricultural Research (ICAR) analysed >240,000 soil samples from 2012 to 2018 from 28 states of India and reported ~38% soil Zn deficiency in the Indian soils. There is no programme in India that currently maps micronutrients in soil and crops together using “GeoNutrition” approaches recently reported in two countries in Africa, Ethiopia, and Malawi. Future co-ordinated soil and crop micronutrient mapping in India can help us to understand better the movement of Zn (and other micronutrients) in food systems and to inform strategies to improve the Zn status in the soil, e.g., the use of Zn fertilisers for yield and agronomic biofortification, and in the edible tissues of crops, e.g., through genetic biofortification.

Agronomic Biofortification of Plants with Iodine and Selenium: A Potential Solution for Iodine and Selenium Deficiencies.

Iodine and selenium deficiencies are widespread both in developed countries and developing countries. The soil is the fundamental source of iodine and selenium for plants, and iodine and/or selenium-depleted soil restrains the cultivation of crops to cover recommended daily intakes of iodine and selenium. Although food fortification strategies, including salt iodization, increase the dietary intake of these minerals, their global deficiencies have not been eliminated. Therefore, new strategies have been developed to prevent iodine and selenium deficiencies, and biofortification is one of them. The aim of this review is to assert the outcomes of the studies that investigate the optimum conditions for biofortification with iodine and selenium and to recognize the role of biofortification practices as a potential solution for preventing iodine and selenium deficiencies. The findings of studies show that biofortification with iodine and selenium can be a solution for iodine and selenium deficiencies. Agronomic biofortification is currently a more convenient method to increase selenium and iodine contents in plants. However, the most effective agronomic biofortification conditions are crucial to acquire biofortified food. Moreover, increasing the awareness of the producers and consumers on biofortification has a determinative role in the achievement of biofortification practices for human health. Although research about iodine and selenium biofortification has been increased, the effectiveness of biofortified foods to meet recommended daily intakes is still unknown. More research is needed to understand most effective biofortification conditions for plants and bioavailability of biofortified foods for humans.

Yield and quality of different wheat cultivars as influenced by agronomic biofortification of N, K, S and Zn through foliar sprays in North-Western India

Agronomic bio-fortification remains a crucial focus area for enhancing wheat productivity and quality while alleviating environmental pressures. Micronutrient deficiencies, particularly in iron (Fe) and zinc (Zn), persist among the Indian population, especially affecting women. These deficiencies can be effectively addressed through agronomic bio-fortification of wheat grains. To tackle this issue, a comprehensive multilocation (4) field experiment was conducted, incorporating four high-yielding wheat cultivars (HD-3226, HI-1544, DBW-187, and PBW-1-Zn) alongside six foliar fertilizer applications (Control, 2% S, 2% N, 0.5% ZnSO4.7H2O, 1% KCl, and combined treatments) during 2021-22 and 2022-23 utilizing a split-plot design with three replications. Analysis over the years revealed that significant impacts of location and cultivar on yield and its attributes, and Fe, Zn, and protein content of grains. Warmer locations like Hisar exhibited higher yields primarily due to significantly increased earheads/m2 and grains number/m2 compared to other locations. Moreover, Fe content in wheat grains was notably higher in Gurdaspur followed by Hisar, surpassing Ludhiana. Notably, cultivar DBW-187 outperformed others with a 14.75% higher grain yield than the least yielding cultivar, HI-1544. PBW-1-Zn exhibited the highest grain Fe and Zn content among the cultivars studied. The interaction between cultivar and location significantly influenced all yield parameters and grain Fe content. Foliar spray of ZnSO4 (0.5%) during stem elongation and milk stages resulted in significantly higher grain Zn content compared to applications of KCl (1.0%), N (2.0%), and S (2.0%) alone, with an increase of 9.9% over no spray. In conclusion, the selection of appropriate cultivars tailored to specific regions, coupled with strategic agronomic bio-fortification approaches, is imperative for enhancing wheat productivity and grain quality, thereby ensuring nutritional security.

Soil and Foliar Zinc Biofortification of Triticale (x Triticosecale) under Mediterranean Conditions: Effects on Forage Yield and Quality.

Zinc (Zn) deficiency represents a significant global concern, affecting both plant and human health, particularly in regions with Zn-depleted soils. Agronomic biofortification strategies, such as the application of Zn fertilizers, offer a cost-effective approach to increase Zn levels in crops. This study aimed to assess the efficacy of soil and foliar Zn biofortification, applied as an aqueous solution of 0.5% zinc sulphate (ZnSO4·7H2O), on triticale (x Triticosecale) grown under Mediterranean conditions. The study was conducted over two growing seasons (2017/18 and 2018/19) in southern Spain, evaluating the effects on biomass yield; forage quality, including crude protein, Van Soest detergent fiber, organic matter digestibility, and relative forage value; and nutrient accumulation. Soil treatment consisted in the application of 50 kg of ZnSO4·7H2O ha-1 solely at the beginning of the first campaign to assess the residual effect on the second year. In contrast, the foliar treatment consisted of two applications of 4 kg of ZnSO4·7H2O ha-1 per campaign, one at the beginning of tillering and the other at the appearance of the first node. The foliar application increased the Zn content of the forage to adequate levels, while the soil application resulted in a 33% increase in biomass production, which is particularly beneficial for farmers. Overall quality was favored by the combined soil + foliar application, and no adverse antagonistic effects on other nutrients were detected. Instead, a synergistic interaction between Se and Zn was observed, which improved the efficacy of this important micronutrient for livestock and human wellbeing.

Biofortifying drought-tolerant rice: enhancing growth and nutritional quality with foliar iron and zinc applications in Eastern India

Micronutrient deficiencies in staple food crops pose a significant global health concern, especially in regions prone to drought. Agronomic biofortification offers a promising solution by enhancing the content of essential micronutrients. This study aims to identify efficient rice varieties for iron (Fe) and zinc (Zn) biofortification through foliar applications. A field experiment was carried out during kharif season in 2019 and 2020 with four drought-tolerant rice varieties (Swarna Shreya, Swarna Shakti Dhan, Sahbhagi Dhan, and DRR Dhan 42) were assessed under four foliar applications of Fe and Zn (control, 1% of Fe, 1% of Zn and combined 1% of Fe + 1% of Zn) at Indian Council of Agricultural Research-Research Complex for Eastern Region (ICAR-RCER), Patna. The highest grain yield of 5.65 t/ha was attained with the main plot treatment, Swarna Shreya variety, and in the subplot treatment, Fe + Zn foliar application resulted in a yield of 5.50 t/ha. The combined foliar application of Fe + Zn demonstrates the highest chlorophyll content and starch synthesis. Foliar application of combined Fe and Zn increased paddy grain Fe and Zn concentration by up to 30 and 16%, respectively, compared to the control. This finding is important for addressing micronutrient deficiencies in regions where rice is a dietary staple. Thus, Swarna Shreya, in combination with iron and zinc foliar application is a promising option for enhancing yield and fortifying grains in rainfed areas of eastern India.

Agronomic biofortification of finger millet for zinc, and its influence on yield and partitioning of zinc, iron, and calcium in the plant

Zinc (Zn) deficiency in humans is the most common, and zinc requirement is catered mainly by cereal food grains which have lower zinc content. Finger millet is one of the staple food crops in Africa and India and has only 25 to 30 µg Zn g−1 of grain. Breeding efforts have improved the grain-Zn content to nearly 40 µg g−1 of grain, which is far below the recommended dietary allowance of 15 mg day−1 adult−1, and such varieties are not suited to all the finger millet cultivation regions. Therefore, the objective of the present studies is to enhance the grain-Zn content of locally adapted varieties through agronomic biofortification, which can be adapted for any variety and region. The easy, promising, and cost-effective approach is the soil or foliar application of zinc to increase the grain-Zn content. Present studies over four years revealed that the foliar application of 0.5% ZnSO4·7H2O solution at flowering and 20 days after flowering (DAF) is apt to increase the grain-Zn significantly to 40 µg g−1 of grain. Whereas the soil application of ZnSO4·7H2O at 12.5 kg ha−1 is appropriate to increase the grain yield to 504 g m−2 from 444 g m−2 in the control. The partitioning of zinc and calcium was higher toward the leaf sheath, leaf lamina, and husk than the other plant parts, whereas iron was toward the root. Therefore, the translocation of zinc from leaves to grain needs to be improved for further increase in grain-zinc of finger millet.

Genetic Biofortification of Winter Wheat with Selenium (Se).

Wheat is one of the three most important cereals in the world, along with rice and maize. It serves as the primary food and source of energy for about 30-40% of the world's population. However, the low levels of micronutrients in wheat grains can lead to deficiencies of those micronutrients in people whose dietary habits are mostly based on cereals such as wheat. Apart from iron (Fe) and zinc (Zn), a lack of selenium (Se) is also one of the biggest problems in the world. The essentiality of Se has been confirmed for all animals and humans, and the lack of this micronutrient can cause serious health issues. Wheat dominates the world's cereal production, so it is one of the best plants for biofortification. Due to the fact that agronomic biofortification is not an economical or environmentally acceptable approach, genetic improvement of cereals such as wheat for the enhanced content of micronutrients in the grain represents the most efficient biofortification approach.

Zinc and iron biofortification of crops grown in a vertical farm

With the growing global population and climate change, achieving food security is a pressing challenge(1). Vertical farming has the potential to support local food production and security. In the UK population females and younger adults appear to be particularly vulnerable to micronutrient shortfalls from food sources alone. Levels of micronutrient intakes including zinc and iron are below the recommended daily intake(2). As a Total Controlled Environment Agriculture (TCEA) system, vertical farming employs hydroponics using a nutrient solution which offers opportunities to modulate nutrient uptake, and thus influence plant mineral and vitamin composition(3).In this study we aimed to determine the suitability of different crop types for soilless agronomic biofortification with zinc and iron to achieve biofortified crops.In this study, we investigated the effect of the addition of 20ppm (+20 mg L−1) of zinc (ZnSO4) or iron (Fe-EDTA) to the nutrient solution on the growth and nutritional components in pea microgreens, kale microgreens and kale baby leaf plants. The growth conditions were kept identical throughout the treatments with photoperiod 18 h d-1, temperature 20-22°C and relative humidity at 70-80%. Plant growth, mineral composition, glucosinolate content and protein content were evaluated. Results were analysed using ANOVA (p<0.05, Tukey’s test).It was determined that higher amounts of zinc in the nutrient solution resulted in significantly higher levels of zinc in all three crops (p<0.05), with increases of 205% in pea microgreens, 264% in babyleaf kale and 217% in kale microgreens compared to the control plants. Higher amounts of iron in the nutrient solution resulted in significantly higher levels of iron only in pea microgreens, with an increase of 38% (p<0.05). Neither dosing regimen negatively influenced the overall crop performance.These results suggest that the three different crops are suitable for soilless biofortification with zinc and iron, although pea microgreens were the only crop that had a significant increase in iron upon iron-dosing.

Modulation of cherry tomato performances in response to molybdenum biofortification and arbuscular mycorrhizal fungi in a soilless system

Molybdenum (Mo) is a crucial microelement for both, humans and plants. The use of agronomic biofortification techniques can be an alternative method to enhance Mo content in vegetables. Concomitantly, arbuscular mycorrhizal fungi (AMF) application is a valuable strategy to enhance plant performances and overcome plant abiotic distresses such as microelement overdose. The aim of this research was to estimate the direct and/or indirect effects of Mo supply at four doses [0.0, 0.5 (standard dose), 2.0 or 4.0 μmol L−1], alone or combined with AMF inoculation, on plant performances. In particular, plant height and first flower truss emission, productive features (total yield, marketable yield and average marketable fruit weight) and fruit qualitative characteristics (fruit dry matter, soluble solids content, titratable acidity, ascorbic acid, lycopene, polyphenol, nitrogen, copper, iron and molybdenum) of an established cherry tomato genotype cultivated in soilless conditions were investigated. Moreover, proline and malondialdehyde concentrations, as well as Mo hazard quotient (HQ) in response to experimental treatments were determined. A split-plot randomized experimental block design with Mo dosages as plots and +AMF or -AMF as sub-plots was adopted. Data revealed that AMF inoculation enhanced marketable yield (+50.0 %), as well as some qualitative traits, such as fruit soluble solids content (SSC) (+9.9 %), ascorbic acid (+7.3 %), polyphenols (+2.3 %), and lycopene (+2.5 %). Molybdenum application significantly increased SSC, polyphenols, fruit Mo concentration (+29.0 % and +100.0 % in plants biofortified with 2.0 and 4.0 μmol Mo L−1 compared to those fertigated with the standard dose, respectively) and proline, whereas it decreased N (−25.0 % and −41.6 % in plants biofortified with 2.0 and 4.0 μmol Mo L−1 compared to those fertigated with the standard dose, respectively). Interestingly, the application of AMF mitigated the detrimental effect of high Mo dosages (2.0 or 4.0 μmol L−1). A pronounced advance in terms of plant height 45 DAT, fruit lycopene concentration and fruit Fe, Cu and Mo concentrations was observed when AMF treatment and Mo dosages (2.0 or 4.0 μmol Mo L−1) were combined. Plants inoculated or not with AMF showed an improvement in the hazard quotient (HQ) in reaction to Mo application. However, the HQ - for a consumption of 200 g day−1 of biofortified cherry tomato - remained within the safety level for human consumption. This study suggests that Mo-implementation (at 2.0 or 4.0 μmol L−1) combined with AMF inoculation could represent a viable cultivation protocol to enhance yield, produce premium quality tomato fruits and, concomitantly, improve Mo dose in human diet. In the light of our findings, further studies on the interaction between AMF and microelements in other vegetable crops are recommended.

Tracing isotopically labeled selenium nanoparticles in plants via single-particle ICP-mass spectrometry

Agronomic biofortification using selenium nanoparticles (SeNPs) shows potential for addressing selenium deficiency but further research on SeNPs-plants interaction is required before it can be effectively used to improve nutritional quality. In this work, single-particle inductively coupled plasma-mass spectrometry (SP-ICP-MS) was used for tracing isotopically labeled SeNPs (82SeNPs) in Oryza sativa L. tissues. For this purpose, SeNPs with natural isotopic abundance and 82SeNPs were synthesized by a chemical method. The NPs characterization by transmission electron microscopy (TEM) confirmed that enriched NPs maintained the basic properties of unlabeled NPs, showing spherical shape, monodispersity, and sizes in the nano-range (82.8 ± 6.6 nm and 73.2 ± 4.4 nm for SeNPs and 82SeNPs, respectively). The use of 82SeNPs resulted in an 11-fold enhancement in the detection power for ICP-MS analysis, accompanied by an improvement in the signal-to-background ratio and a reduction of the size limits of detection from 89.9 to 39.9 nm in SP-ICP-MS analysis. This enabled 82SeNPs to be tracked in O. sativa L. plants cultivated under foliar application of 82SeNPs. Tracing studies combining SP-ICP-MS and TEM-energy-dispersive X-ray spectroscopy data confirmed the uptake of intact 82SeNPs by rice leaves, with most NPs remaining in the leaves and very few particles translocated to shoots and roots. Translocation of Se from leaves to roots and shoots was found to be lower when applied as NPs compared to selenite application. From the size distributions, as obtained by SP-ICP-MS, it can be concluded that a fraction of the 82SeNPs remained within the same size range as that of the applied NP suspension, while other fraction underwent an agglomeration process in the leaves, as confirmed by TEM images. This illustrates the potential of SP-ICP-MS analysis of isotopically enriched 82SeNPs for tracing NPs in the presence of background elements within complex plant matrices, providing important information about the uptake, accumulation, and biotransformation of SeNPs in rice plants.

Agronomic Biofortification Increases Concentrations of Zinc and Storage Proteins in Cowpea Grains

Zinc (Zn) is crucial for both plant metabolism and human nutrition, with its deficiency being a global health concern. Strategies to increase its availability in food, such as agronomic biofortification, have gained prominence. This study evaluated the impact of foliar spraying of Zn [at full bloom stage: 0 (control) and 600 g ha−1, as ZnSO4⋅7H2O] on the nutritional quality of cowpea (Vigna unguiculata L. Walp.) grains. Field experiments involving 20 cowpea genotypes were carried out over two seasons in a Typic Quartzipsamment under a no-tillage system. The photosynthetic responses of cowpea plants and the concentrations of Zn, amino acids, sucrose, total sugars, and storage proteins (glutelin, albumin, prolamin, and globulin) in grains were analyzed. All genotypes showed enrichment of Zn in grains in response to ZnSO4⋅7H2O application compared to untreated plants. Foliar spraying of ZnSO4⋅7H2O during initial grain filling was ideal for increasing Zn concentration in grains and improving plant physiological processes. Additionally, Zn fertilization led to higher concentrations of storage and total amino acids and proteins in the grains, supporting the rational application of Zn in cowpea production to improve the nutritional quality of grains and increase plant productivity.