Zinc In Rice Research Articles

Feasibility Analysis of Inpari IR Nutri Zinc Rice Seed Farming in Irrigated Paddy Fields in Riau Province

Feasibility Analysis of Inpari IR Nutri Zinc Rice Seed Farming in Irrigated Paddy Fields in Riau Province

An Ex-Ante Analysis of the Impact of Biofortified Zinc Rice on Dietary Zinc Inadequacy: Evidence from Bangladesh, Indonesia, and the Philippines

BackgroundSouth, East, and Southeast Asia are among the regions of the world with the highest estimated prevalence of inadequate zinc intake. Because populations in those regions eat rice as their main staple, zinc biofortification of rice can potentially improve zinc intake, especially among the most vulnerable. ObjectivesWe modeled the impact of the consumption of zinc-biofortified rice on zinc intake and inadequacy among women of childbearing age and young children nationally in Indonesia, the Philippines, and at a subnational level in Bangladesh. MethodsWe conducted an ex-ante analysis by applying increments of zinc content in rice, from a baseline level of 16 parts per million (ppm) to 100 ppm, and based on rice consumption data to substitute levels of conventional rice with zinc-biofortified rice varying between 10% and 70%. ResultsAmong all datasets evaluated from these 3 countries, the prevalence of dietary zinc inadequacy at baseline was 94%–99% among women of childbearing age, 77%–100% among children 4–5 y old, and 27%–78% among children 1–3 y old. At the current breeding target of 28 ppm, zinc-biofortified rice has the potential to decrease zinc inadequacy by ≤50% among women and children in rural Bangladesh and among children in the Philippines where consumption of rice is higher compared with Indonesia. ConclusionsOur analysis shows that increasing zinc content in rice ≤45 ppm reduces the burden of zinc inadequacy substantially, after which we encourage programs to increase coverage to reach the highest number of beneficiaries.

Hydrogen peroxide positively regulates ABA signaling via oxidative modification of the C2H2-type zinc finger protein ZFP36 in rice

The rice zinc finger protein ZFP36 serves as a pivotal regulator of the hydrogen peroxide (H2O2) signaling pathway in response to abscisic acid (ABA). Its role is crucial for integrating H2O2 signals with the plant defense mechanisms against water deficit and oxidative stress. However, it remains unclear whether ZFP36 directly modulates ABA-induced H2O2 signaling. This study explored the effects of oxidative post-translational modifications (OxiPTMs) on ZFP36 in rice, with an emphasis on the H2O2-induced oxidation through its cysteine (Cys) residues. We found that ZFP36 undergoes oxidative modification as a target of H2O2 in the presence of ABA, specifically at Cys32. Employing quantitative detection and fluorescence assays, we observed that ZFP36 oxidation enhances the expression and activity of genes encoding protective antioxidant enzymes. Moreover, our investigation into the thioredoxin (Trx) and glutaredoxin (Grx) families revealed that OsTrxh1 facilitates the reduction of oxidized ZFP36. Genetic evidence indicates that ZFP36 positively influences rice resilience to oxidative and water stress, while OsTrxh1 exerts an opposing effect. These insights reveal a distinctive pathway for plant cells to perceive ABA-induced H2O2 signaling, advance our comprehension of H2O2 signaling dynamics, and ABA-related plant responses, and lay a vital groundwork for enhancing crop stress tolerance.

Zinc regulation of chlorophyll fluorescence and carbohydrate metabolism in saline-sodic stressed rice seedlings

Saline-sodic stress can limit the absorption of available zinc in rice, subsequently impacting the normal photosynthesis and carbohydrate metabolism of rice plants. To investigate the impact of exogenous zinc application on photosynthesis and carbohydrate metabolism in rice grown in saline-sodic soil, this study simulated saline-sodic stress conditions using two rice varieties, 'Changbai 9' and 'Tonghe 899', as experimental materials. Rice seedlings at 4 weeks of age underwent various treatments including control (CT), 2 μmol·L−1 zinc treatment alone (Z), 50 mmol·L−1 saline-sodic treatment (S), and 50 mmol·L−1 saline-sodic treatment with 2 μmol·L−1 zinc (Z + S). We utilized JIP-test to analyze the variations in excitation fluorescence and MR820 signal in rice leaves resulting from zinc supplementation under saline-sodic stress, and examined the impact of zinc supplementation on carbohydrate metabolism in both rice leaves and roots under saline-sodic stress. Research shows that zinc increased the chloroplast pigment content, specific energy flow, quantum yield, and performance of active PSII reaction centers (PIABS), as well as the oxidation (VOX) and reduction rate (Vred) of PSI in rice leaves under saline-sodic stress. Additionally, it decreased the relative variable fluorescence (WK and VJ) and quantum energy dissipation yield (φDO) of the rice. Meanwhile, zinc application can reduce the content of soluble sugars and starch in rice leaves and increasing the starch content in the roots. Therefore, the addition of zinc promotes electron and energy transfer in the rice photosystem under saline-sodic stress. It enhances rice carbohydrate metabolism, improving the rice plants’ ability to withstand saline-sodic stress and ultimately promoting rice growth and development.

Application of Planting System and Organic Fertilizer on the Yield of Inpari IR Nutri Zinc in Lampung

The low rice productivity in Lampung needs to be increased. The objectives of this study were to introduce new superior Inpari IR Nutri Zinc rice and determine the effect of planting systems and biofertilizer on the growth and yield of Inpari IR Nutri Zinc rice in technically irrigated rice fields in Lampung. The experiment was carried out in technically irrigated rice fields in Kalirejo Village, Negeri Katon District, Pesawaran Regency, Lampung Province, using a split-plot design in a randomized block design with three replications. The treatments tested were three rice planting systems as the main plot and the dose of biofertilizer as a sub-plot. The parameters observed components of growth and yield components. Data were analyzed with the SAS software 5.4 version. The results showed that the application of biofertilizers gave effects on rice yield. From the results of this study, it can be concluded that the use of biofertilizers can increase rice yields by 10-12% compared to those without biofertilizers, in the three cropping systems. The application of biofertilizers resulted in the highest harvested dry grain production, namely 6.61 tons per hectare and significantly different than that without biofertilizers, namely 5.96 tons per hectare. The production of dry grain harvested by the three cropping systems was not significantly different at an average of 6.28 tons per hectare.

Genetic gain and selection of stable genotypes in high zinc rice using AMMI and BLUP based stability methods

Rice is the staple food of almost half of the world’s population, impacting nutrition especially in children, pregnant women, and nursing mothers. Because the traits were quantitatively inherited, they are affected by changes in location and year. A RBD with three replications was used to identify superior and stable high-zinc rice genotypes in Uttar Pradesh, India. Grain zinc content (GZC) is negatively correlated with grain yield using genetic association study. There was a significant G × E interaction (GEI) and V16 and V21 for GYP and V9, V2 and V10 for GZC were identified as stable based on the AMMI model and bi-plot. V11, V5, V21 for grain yield per plant (GYP) and for GZC, V14, and V10 are found to be stable and common in all AMMI stability parameters. V6, V13 and V5 for GYP and V10, V8 and V2 for GZC were identified as stable based on the mean vs. WAASB bi-plot. V21 for GYP and V4 for GZC was the highest yielder and widely adaptable based on WAASBY scores. V13 for GYP and V1 for GZC were all-time winners. V13 and V1 have the highest predicted mean for GYP and GZC, respectively, based on BLUP. V6, V21and V13 were identified as stable and selected based on the multi-trait stability index (MTSI). These selected genotypes selected through BLUP-based stability methods, MTSI, and strength and weakness plots make it easier to evaluate and select genotypes for varietal recommendations and future Zn-fortified rice breeding studies.
 Keywords: GEI, High Zinc Rice, MTSI, Stable genotype

Improving grain yield and quality by enhancing accumulation of zinc in rice under subtropical condition

One of the primary abiotic factors limiting rice production is zinc (Zn) deficiency. Effective management of Zn in rice soils is crucial, as rice is a staple crop for many nations. To address this issue, a pot trial was conducted at the net house of the Department of Agronomy, Bangladesh Agricultural University, Mymensingh,from December 2019 to May 2020. The trail aimed to assess the impact of zinc on yield performance and grain zinc content of rice. The experiment employed a completely randomized design (CRD) with three replications, involving the applications of six different rates of Zn to three distinct varieties of boro rice. The result revealed that BRRI dhan28 exhibited superior yield and yield-related traits when treated with 12 kg Zn ha-1. Meanwhile, the application of 10 kg Zn ha-1 resulted in the highest Zn content in the grain of BRRI dhan74, considering the quantity of Zn accumulated by the grain. Based on the findings of the study, it can be concluded that applying 12 kg of Zn ha-1 is likely the optimal Zn management strategy to achieve outstanding performance in the rice cultivar BRRI dhan28. Furthermore, applying 10 kg of Zn ha-1 may enhance the Zn content of the grain in BRRI dhan74.

Exploring the Hidden Potential of Traditional Rice Landraces and Mutants for Iron and Zinc Concentration in Brown Rice to Develop Bio-fortified Rice Varieties

In the present study, 58 rice genotypes were evaluated for three consecutive seasons to enucleate the elite lines with high Fe and Zn contents. ANOVA revealed significant differences among the genotypes for Fe and Zn contents during all three seasons. Furthermore, PCV and GCV were moderate to high for Fe and Zn content during all three seasons. Similarly, high level of heritability and genetic advance were also recorded for both the traits. Iron content of Safri mutant 17-2-48 was consistently high for all the seasons whereas zinc content of Loktimachi was high for two seasons. Interestingly, rice genotypes Chhindmauri, Badsahbhog, Rudra, Danighoda and Suapankhi have been identified to have moderate to high Fe and Zn contents which could be used as donors for developing bio-fortified rice varieties. Stability analysis revealed that the genotypes Jhimiprass, Loktimachi, and CG Zinc Rice 2 for iron content and Rela Dhan, Chhindmauri, and CG Zinc Rice-1 for zinc content have had an average response to environment, making them appropriate for all seasons

The potential of irradiated inoculants consortium for zinc accumulation in rice mutant lines

Some of the microorganisms in soil play important roles in plant performance by improving mineral nutrition. Zinc (Zn) is an essential micronutrient that has various important functions and is only obtained by the intake of foods. Rice is a staple food for Indonesian people. Increasing Zn concentration in rice through fertilization and gamma irradiated inoculants consortium is an effective way to accumulate Zn in rice grains. The objective of this research was to utilize gamma-irradiated inoculants and enhancement of Zn content in rice mutant lines. This study used inoculants consortium from potential microorganisms consisting of Aspergillus niger, Azotobacter sp, Bacillus circulants, and Trichoderma harzianum. They can be used to solubilize metals or minerals that are accumulated in part of the plants. The irradiation of the inoculant was conducted by 250 Gy gamma rays. Seven Mira-1 rice mutant lines together with their wild type, Inpari Nutri Zinc rice variety, were used. Treatment combinations, i.e., Control, T1, T2, T3, T4, and T5 were applied to the rice materials randomized block experimental design with three replications. Agronomic characteristics at the vegetative phase were observed and Zn content in rice grain was measured by atomic absorption spectrophotometry. The result shows significant differences in agronomic characteristics from different treatments. Zn content in rice mutant lines was higher than their wild type, and the irradiated inoculants consortium was very effective in enhancing Zn content in rice grains. The best treatment for accumulation of Zn in rice grain was irradiated inoculants consortium combined with 10 kg/ha zinc sulfate (treatment T4), resulting in a grain Zn content of 72.19 ppm in the 82 rice mutant line.

Concomitant Activation of OsNAS2 and OsNAS3 Contributes to the Enhanced Accumulation of Iron and Zinc in Rice

Nicotianamine (NA) is produced by NA synthase (NAS), which contains three genes in rice and is responsible for chelating metals such as iron (Fe) and zinc (Zn), as well as preserving metal homeostasis. In this study, we generated a transgenic plant (23D) that shows simultaneous activation of OsNAS2 and OsNAS3 by crossing two previously identified activation-tagged mutants, OsNAS2-D1 (2D) and OsNAS3-D1 (3D). Concomitant activation of both genes resulted in the highest Fe and Zn concentrations in shoots and roots of the 23D plants grown under normal conditions and Fe and Zn limited growth conditions. Expression of genes for the biosynthesis of mugineic acid family phytosiderophores (MAs) and Fe and Zn uptake were enhanced in 23D roots. Additionally, 23D plants displayed superior growth to other plants at higher pH levels. Importantly, 23D seeds had NA and 2'-deoxymugineic acid (DMA) concentrations that were 50.6- and 10.0-fold higher than those of the WT. As a result, the mature grain Fe and Zn concentrations of the 23D plant were 4.0 and 3.5 times greater, respectively, than those of the WT. Furthermore, 23D plants exhibited the greatest resistance to excess metals. Our research suggests that simultaneous activation of OsNAS2 and OsNAS3 can enhance Fe and Zn accumulation in rice grains while also increasing plant tolerance to growing situations with metal deficiency and excess metal availability.

Insights into the recent approaches for rice (Oryza sativa L.) biofortification

Rice is the most essential source of calories for humans among the cereals and over half of the world's population is fed on rice. As part of a complete food systems approach, biofortification is an effective technique for nutrition enrichment which refers to the development of micronutrient-rich diet by utilising traditional breeding practises and sophisticated biotechnological tools. To enhance the profile of rice grain for biofortification-related properties, researchers must first understand the genetics of critical biofortification characteristics. Significant increases in micronutrients like iron and zinc, as well as many other important minerals and provitamins are acquired in rice grain using the biofortification strategies. Most indica and japonica rice types have been biofortified over the world, giving them the titles of high iron rice, low phytate rice, high zinc rice, and high carotenoid rice or golden rice. Some of the recent approaches towards rice biofortification, as well as their effects, have been explored in this article.

Rice Diversity of Inpari IR Nutri Zinc Variety in Three Clanning Seasons in West Nusa Tenggara

The spread of the Corona virus (Covid 19) is still developing with new variants, Indonesia is one of the countries that currently has not been able to overcome the pandemic. One of the ways to maintain the immune system is by maintaining nutritious food intake and consuming healthy foods. Deficiency of Zn in the body results in decreased endurance, productivity, and human quality of life. Zn deficiency is one of the causes of stunting. Inpari IR Nutri Zinc is biofortified rice with a zinc content of 34.51 ppm which plays a role in preventing stunting, helping to increase nutritional value while overcoming iron deficiency in the community. Based on the superiority of Inpari IR Nutri Zinc rice, it is necessary to study the productivity and suitability of agro-ecosystems on Lombok Island. The study was carried out in three locations, three growing seasons using Standard Operating Procedures (SOP) for IR Nutri Zinc Inpari Rice Cultivation. The three locations are Mataram District at MT I/2020, Gerung District MT II/2020 and Narmada District MT III/2020. The study was carried out using a Randomized Block Design (RBD) design in 3 locations, 3 growing seasons using the Standard Operating Procedure (SOP) for IR Nutri Zinc Inpari Rice Cultivation. The aim of the study was to determine the level of productivity consistency of the Inpari IR Nutri Zinc variety using the Standard Operating Procedure (SOP) for rice cultivation at the 3 locations. The planting of Inpari IR Nutri Zinc rice at each location and growing season was repeated 5 times. Parameters observed included agronomic growth and productivity. Data collection consists of secondary data (rainfall data) and primary data. For primary data carried out by direct observation in the field and interviews with implementing farmers and business actors. Inpari IR Nutri Zinc planted in 3 locations using standard operating procedures (SOP) for rice cultivation, showed higher productivity than the average yield of Inpari IR Nutri Zinc at the national level. The productivity of rice planted in the Mataram sub-district in MH 2020 was 7.63 t/ha. The planting of Inpari IR Nutri Zinc rice is suitable for planting in the rainy season, but can produce well in the dry season with water conditions or an average rainfall of at least 100 mm / growing season. Rice Inpari Nutri Zinc can and should be developed in West Nusa Tenggara Province, especially in paddy fields and districts where the stunting rate is still quite high in an effort to reduce and prevent stunting in West Nusa Tenggara.

Effect of Leaf Surface Regulation of Zinc Fertilizer on Absorption of Cadmium, Plumbum and Zinc in Rice (Oryza sativa L.)

The accumulation of heavy metals in rice is bound to affect human health and safety. In order to ensure food security, this study explores the effect of leaf surface regulation of zinc (Zn) fertilizer on the safety of rice in cadmium (Cd)-plumbum (Pb) polluted farmland. Through field experiments, the leaf surface control treatment of zinc fertilizer was set up, and the effects of leaf surface control of zinc fertilizer on rice yield, Cd and Pb concentration in different parts and zinc, nitrogen, phosphorus and potassium concentration in brown rice were studied in the growing period of rice. The results showed as follows: (1) Spraying twice or more in the growth stage of rice could increase the yield by 6.77–7.29% compared with the blank, which was significantly higher than that of single spraying in a certain growth stage. (2) After spraying zinc fertilizer on the leaf surface, Cd and Pb concentration in brown rice decreased by 29.52–56.01% and 11.10–28.34%, respectively, compared with CK. Two or more times of spraying can make Cd concentration in brown rice meet the Chinese standard GB 2762-2022, and one time of spraying can make Pb concentration in brown rice meet the standard. (3) Leaf surface control of zinc fertilizer could reduce the Cd enrichment ability of rice plant parts, and the Cd enrichment coefficient of brown rice was significantly reduced by 28.18–55.02%. Leaf surface control of zinc fertilizer can reduce Cd and Pb concentration in brown rice by reducing the transport ability of heavy metal Cd and Pb in rice roots to straw and then to brown rice. (4) The zinc concentration in brown rice was 18.16–20.68 mg·kg−1, which was 18.21–34.64% higher than that in CK, and the zinc enrichment effect was the most significant after spraying three times. Meanwhile, the nitrogen, phosphorus and potassium concentration in brown rice also increased with the increase of spraying times. By comprehensive analysis, the leaf surface control of zinc fertilizer can reduce the Cd and Pb concentration in rice, and the Cd and Pb concentration in brown rice can meet the Chinese standard GB 2762-2022 by spraying twice. At the same time, it can improve the concentration of zinc, nitrogen, phosphorus and potassium in brown rice, is feasible and has high economic benefits.

Proof of concept and early development stage of market-oriented high iron and zinc rice expressing dicot ferritin and rice nicotianamine synthase genes

Micronutrient deficiencies such as iron (Fe), zinc (Zn), and vitamin A, constitute a severe global public health phenomenon. Over half of preschool children and two-thirds of nonpregnant women of reproductive age worldwide have micronutrient deficiencies. Biofortification is a cost-effective strategy that comprises a meaningful and sustainable means of addressing this issue by delivering micronutrients through staple foods to populations with limited access to diverse diets and other nutritional interventions. Here, we report on the proof-of-concept and early development stage of a collection of biofortified rice events with a high density of Fe and Zn in polished grains that have been pursued further to advance development for product release. In total, eight constructs were developed specifically expressing dicot ferritins and the rice nicotianamine synthase 2 (OsNAS2) gene under different combinations of promoters. A large-scale transformation of these constructs to Bangladesh and Philippines commercial indica cultivars and subsequent molecular screening and confined field evaluations resulted in the identification of a pool of ten events with Fe and Zn concentrations in polished grains of up to 11 μg g−1 and up to 37 μg g−1, respectively. The latter has the potential to reduce the prevalence of inadequate Zn intake for women of childbearing age in Bangladesh and in the Philippines by 30% and 50%, respectively, compared to the current prevalence. To our knowledge, this is the first potential biotechnology public-sector product that adopts the product cycle phase-gated approach, routinely applied in the private sector.

Characterization of Fortified Rice (Fortivit) and Biofortified Rice (Nutri Zinc)

In overcoming Iron Deficiency Anemia and stunting, the Indonesian government seeks to increase the content of iron (Fe) and zinc (Zn) in milled rice through fortification and biofortification. Fortivit rice is rice fortification produced by BULOG. Inpari Nutri Zinc is biofortified rice grown from plant breeding by the Ministry of Agriculture, which ID Food currently produces. This study is a continuation of the IFFRI research collaboration on the Implementation and Research of Precision Agriculture in Biofortified Rice Strain. This study aimed to characterize the biofortified rice as a result of fertilization recommendations in previous studies and compare biofortified rice with fortified rice in several aspects, including micronutrient contents especially Zn, organoleptic, and production
 costs. The highest Zn content of Nutri Zinc was found in the aleuron, so that the post-harvest process caused a decrease in Zn level. The differences in fertilization recommendations have an impact on the Zn content in brown rice, each layer of aleurone, and the rice endosperm. The nutritional content of Fortivit and Nutri Zinc rice was relatively the same as non-fortified/biofortified rice. The washing and cooking process caused a decrease eof about 4 percent in Zn content in fortified rice, while in biofortified rice, there was relatively no decrease. Although there was a decrease in Zn in fortified rice, overall, the Zn content was still much higher than in biofortified rice. Based on the results of the hedonic test, fortifed rice (Fortivit) was the most preferred for all sensory attributes. In biofortified rice (Nutri Zinc), respondents prefer the rice with 100 percent milling grade the most. Fortivit rice had a faster research time and a lower estimated cost in research. In the contrary, it had a higher estimated cost in production than Nutri Zinc rice. Nonetheless, the selling price of Fortivit rice is cheaper than Nutri Zinc rice on the market. 
 keywords: rice, fortification, biofortification, Fe, Zn

Yield attributing traits of high zinc rice (Oryza sativa L.) genotypes with special reference to principal component analysis

Total 21 high zinc rice genotypes were evaluated under five different locations for 14 different yield attributing traits, including grain yield/plant (gm) to determine the pattern of variation, the relationship among the individuals and their characteristics through Principal Component Analysis (PCA) during the Kharif-2017. PCA was done for all the locations individually as well as pooled analysis for all locations using R software. Out of the 14 PCs, the initial four PCs contributed more to the total variability. The highest cumulative variability of the first four PCs found at Bhikaripur (81.11%) followed by BHU Agriculture research farm-II (79.23%) etc. and Pooled variability was 76.61%. Pooled data analysis indicates PCA biplot or loading plot of first two principal components revealed that days to maturity, days to 1st flowering date and days to 50% flowering loaded more on the first component and number of spikelets per panicles, number of grains/panicles, grain weight per panicle, grain yield/plant accounted more variation in the second component compared to the other parameters. Thus, the pooled analysis of principal component analysis revealed the characters contributing to the variation and genetic variability that exists in these rice genotypes. This is because the genotypes BRRIdhan 72, Sambamahsuri and Swarna were identified in different principle components related to grain yield and grain quality, and were also located farthest away from biplot origin in individual PCA based biplot. So they may be employed to improve yield attributing factors like total effective tiller number. PC1, PC2 and PC3 have days to first flowering and days to 50% flowering, hence their genotypes may be valuable in producing early maturing cultivars. Thus, the results revealed that wide range of variability was shown by different traits of the genotypes which can be utilized in rice improvement programmes.

Crop Establishment Methods, Varieties and Levels of Zinc on Growth and Yield of Rice in Chitwan, Nepal

With the aim of identifying the appropriate doses of Zinc in rice for different varieties under various establishment methods, an experiment was carried out in a strip-split plot design with three replications at Agriculture and Forestry University, Rampur, Chitwan during 2015-16. The treatment consists of two crop establishment methods (Transplanted rice (TPR) and Direct Seeded Rice (DSR)) in the vertical strip and two varieties (Hybrid Gorakhnath-509 and Sabitri) in the horizontal strip and four levels of ZnSO4 (0, 15, 30 and 45 kg ha-1) in sub-sub plot. The observations were recorded on growth, yield attributes, grain yield and economics. The research results revealed that the application of ZnSO4 @ 15 Kg ha-1 significantly increased the grain yield of DSR as compared to the non-application of ZnSO4. The higher grain yield of rice was because of increased yield attributes like effective tillers, thousand-grain weight and the number of filled grains per panicle. Crop establishment methods and varieties did not have a significant influence on the grain yield of rice. DSR had a lower cost of cultivation, higher net return and higher benefit-cost ratio as compared to TPR. The variety Sabitri had lower cost of cultivation, higher net return and higher benefit-cost ratio as compared to Gorakhnath-509. Similarly, the application of ZnSO4 @ of 15 Kg ha-1 produced the highest net return and the highest benefit-cost ratio. Therefore, ZnSO4 @ 15 kg ha-1 could be an option for increased yield and net return for DSR in Chitwan.

Agronomic Biofortification of Zinc in Rice for Diminishing Malnutrition in South Asia

Zinc (Zn) is increasingly recognized as an essential trace element in the human diet that mediates a plethora of health conditions, including immune responses to infectious diseases. Interestingly, the geographical distribution of human dietary Zn deficiency overlaps with soil Zn deficiency. In South Asia, Zn malnutrition is high due to excessive consumption of rice with low Zn content. Interventions such as dietary diversification, food fortification, supplementation, and biofortification are followed to address Zn malnutrition. Among these, Zn biofortification of rice is the most encouraging, cost-effective, and sustainable for South Asia. Biofortification through conventional breeding and transgenic approaches has been achieved in cereals; however, if the soil is deficient in Zn, then these approaches are not advantageous. Therefore, in this article, we review strategies for enhancing the Zn concentration of rice through agronomic biofortification such as timing, dose, and method of Zn fertilizer application, and how nitrogen and phosphorus application as well as crop establishment methods influence Zn concentration in rice. We also propose data-driven Zn recommendations to anticipate crop responses to Zn fertilization and targeted policies that support agronomic biofortification in regions where crop responses to Zn fertilizer are high.

Biofortification of iron and zinc in rice and wheat.

Iron and zinc are critical micronutrients for human health. Approximately two billion people suffer from iron and zinc deficiencies worldwide, most of whom rely on rice (Oryza sativa) and wheat (Triticum aestivum) as staple foods. Therefore, biofortifying rice and wheat with iron and zinc is an important and economical approach to ameliorate these nutritional deficiencies. In this review, we provide a brief introduction to iron and zinc uptake, translocation, storage, and signaling pathways in rice and wheat. We then discuss current progress in efforts to biofortify rice and wheat with iron and zinc. Finally, we provide future perspectives for the biofortification of rice and wheat with iron and zinc.

Root Dipping, Foliar and Soil Application of Zinc Increase Growth, Yields, and Grain Zinc in Rice (Oryza sativa L.) Grown in Moderate Zinc Soil of Inceptisol Order

ABSTRACT Zinc (Zn) fertilization not only increased yield of rice but also serves as an economical source of Zn to fight Zn deficiency problems in humans and cattle. A pot experiment was conducted during 2016 (kharif) to study the response of different methods of Zn application on growth, yield, and zinc concentration of rice. Treatments consisted of T1 – without fertilizers (WF); T2 – recommended dose of fertilizer (RDF); T3 – RDF+soil application of 5.0 kg Zn ha−1 (SA5); T4 – RDF + soil application of 7.5 kg Zn ha−1 (SA7.5); T5 – RDF + soil application of 10 kg Zn ha−1 (SA10); T6 – RDF + root dipping in 2% ZnO (RD); T7 – RDF + SA5 + RD; T8 – RDF + foliar application of 0.5% ZnSO4 at tillering and flowering stage (2FA); T9 – RDF + foliar application of 0.5% ZnSO4 at tillering, flowering, and milking stage (3FA); T10 – RDF + SA5 + foliar application of 0.5% ZnSO4 at tillering stage (1FA); T11 – RDF + SA5 + 2FA; and T12 – RDF + SA5 + 3FA. Significantly higher grain and straw yield was obtained in T7 and T6, with a corresponding increase of 17.6 and 30.0% over RDF. Conjoint application of Zn (T7) increased the Zn concentration in grain and straw as compared to RDF, but FA of Zn was more effective than SA. Higher doses of Zn applied increased Zn and manganese (Mn), but decreased the concentration of iron (Fe) and copper (Cu) in grain. Application of 10 kg Zn ha−1 (T5) significantly increased (1.78 folds) the DTPA extractable Zn content in postharvest soil over RDF.