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To investigate the effect of nitrogen fertilizer and zinc (Zn) sulfate on growth, physiological, biochemical, and nutrient use efficiency in fodder maize under drought stress, an experiment was conducted during two cropping years 2019 and 2020. The experiment was performed as a split-factorial in the form of a randomized complete block design with four replications. The main factor was irrigation regimes in three levels: full irrigation (without stress or 100% of field capacity), irrigation based on 75% of field capacity, and irrigation based on 50% of field capacity. The first sub-factor included urea fertilizer at three levels of 0, 69, and 138 kg ha−1. The second sub-factor included foliar application of zinc sulfate at three levels of 0, 2, and 4 mg kg−1. The results showed that the highest fresh weight of maize fodder was obtained under conditions of full irrigation and the use of 138 kg ha−1 of N. The use of zinc at all irrigation levels increased the fresh weight of maize fodder. These results confirmed that if higher amounts of N are used, more zinc should be used to achieve a higher yield of maize forage. With the increase in the severity of drought stress, the concentration of nitrogen and phosphorus in the crop tissue, as well as the efficiency of using nitrogen and phosphorus, decreased. The highest value of nitrogen use efficiency was obtained in full irrigation conditions, using 69 kg ha−1 of N and 4 mg kg−1 of zinc. In addition, at all irrigation levels, the efficiency of using this element decreased with increasing zinc consumption. [ABSTRACT FROM AUTHOR]

The utilization of chelated fertilizers at specific concentrations could serve as an efficient method to mitigate the effects of drought stress in plants, considering it a global climatic issue. The objective of this study was to ascertain the influence of potassium and zinc chelate fertilizers on improving drought tolerance in quinoa plants. The experiment was conducted over two cropping years, 2018–2019 and 2019–2020. It followed a split-plot factorial design within a randomized complete block layout, in three replicates. The results indicated that the foliar application of the combined treatment of 50K + 50Zn significantly increased grain yield, particularly in the Q26 cultivar, under drought-stress conditions. However, the best harvest index was related to the Q26 cultivar under 100Zn application conditions. Nevertheless, the application of chelated fertilizers significantly enhanced these traits under stress compared to the non-application conditions. Furthermore, the content of glycine betaine and proline in the plant increased under the influence of 100K and 100Zn applications in the Q29 cultivar in 25% FC. Based on the obtained results for Catalase enzyme activity at 25% FC and in the presence of 100Zn foliar application and for Peroxidase at 25% FC and the presence of the combined 50K + 50Zn foliar application in the Q29 cultivar, the highest activity of these enzymes was observed. Consequently, considering the increased contents of glycine betaine and proline in the foliar application, as well as the enhanced activity of antioxidant enzymes contributing to improved drought tolerance in these plants, the application of potassium and zinc chelates as fertilizers is recommended. [ABSTRACT FROM AUTHOR]

BACKGROUND: Nanotechnology has been widely applied in agricultural science. During the process of reducing metal toxicity and accumulation in rice, nanomaterials exhibit size effects. However, there is limited knowledge regarding these size effects. We aim to explore the impact of fertilizer with various sizes of ZnO nanoparticles (ZnO‐NPs) on rice growth and cadmium (Cd) accumulation and to elucidate the potential mechanism of Cd reduction in rice. Foliar applications of different concentrations (0.5 and 2 mmol L−1) and different sizes (30 and 300 nm ZnO‐NPs) of zinc (Zn) fertilizer (Zn(NO3)2) were performed to investigate the effects on rice growth, Cd accumulation and subcellular distribution, and the expression of Zn–Cd transport genes. RESULTS: The results suggested that all the foliar sprayings can significantly reduce the Cd concentrations in rice grains by 41–61% with the highest reduction in the application of ZnO‐NPs with large size and low concentration. This is related to the enhancement of Cd fixation in leaf cell walls and downregulation of Cd transport genes (OsZIP7, OsHMA2, OsHMA3) in stem nodes. Foliar ZnO‐NPs applications can increase the Zn concentration in grains by 9–21%. Foliar applications of Zn(NO3)2 and small‐sized ZnO‐NPs promoted plant growth and rice yield, while the application of large‐sized ZnO‐NPs significantly reduced rice growth and yield. CONCLUSION: The study suggests that the rice yield and Cd reduction are dependent on the size and concentration of foliar spraying and the use of large‐sized ZnO‐NPs is the most effective strategy when considering both yield and Cd reduction comprehensively. © 2024 Society of Chemical Industry. [ABSTRACT FROM AUTHOR]

[Objective] Incorporating contemporary research issues into educational curricula is essential in bridging the gap between theoretical knowledge and practical application. This study is designed to integrate the emerging topic of "novel fertilizers" with the fundamental theories of soil science and fertilizer resource development. In particular, this study explores the efficacy of biochar-based zinc fertilizers in increasing the zinc content in rice grains, an essential micronutrient that is often deficient in common diets. Biochar, as a carbon-rich product derived from the pyrolysis of organic materials, is used in this experiment as a carrier for zinc to enhance the soil microenvironment around rice roots, facilitating the uptake of zinc into the rice plants. [Methods] This experiment involved the preparation of biochar-enriched zinc fertilizers and their application to rice paddy fields. The biochar was derived from wheat straw pyrolyzed at 600°C, and zinc oxide nanoparticles (nZnO) were loaded onto the biochar using zinc acetate as a precursor. XRD and SEM analyses confirmed the successful loading of nZnO onto the biochar surface. The pot experiment included eight treatments: (1) no biochar and nZnO (T1), (2) 20 t/ha biochar (T2), (3) 100 kg/ha nZnO (0.5%nZnO, T3), (4) 20 t/ha biochar + 100 kg/ha nZnO (BC+0.5%nZnO, T4), (5) 200 kg/ha nZnO (1.0%nZnO, T5), (6) 20 t/ha biochar + 200 kg/ha nZnO (BC+1.0%nZnO, T6), (7) 200 kg/ha nZnO (2.0%nZnO, T7), and (8) 20 t/ha biochar + 200 kg/ha nZnO (BC+2.0%nZnO, T8). Students measured rice growth, yield, and nutrient content in the plants and grains, analyzing zinc fertilizer utilization and the impact of biochar-based nano-zinc on soil nutrients. The subsequent analyses focused on the bioavailability of zinc in the rhizosphere, i.e., the root zone of the plants. [Results] The results from this study indicate that the application of biochar-based zinc significantly improved the nutrient availability within the rhizosphere. The study observed that the concentration of available zinc in the root soils markedly increased, which, in turn, promoted the accumulation of zinc in both the rice plants and the harvested grains. This increment in zinc content is crucial, considering the role of zinc in enhancing immune function and overall human health. Further analysis confirmed that biochar-based nano-zinc exerted a considerable impact on the microenvironment of the root zone, modifying physical and chemical soil properties in a manner conducive to nutrient uptake. Statistical analysis employing advanced software tools supported these findings, demonstrating a clear trend of enhanced zinc accumulation due to the novel fertilizer application. [Conclusions] This study not only confirms the potential of biochar as an effective carrier for micronutrients like zinc but also illustrates the transformative impact of integrating innovative agricultural inputs with traditional farming practices. Through this study, students engaged in soil science, plant nutrition, agricultural chemical analysis, and related disciplines can enhance their ability to apply theoretical knowledge in analyzing and solving real-world agricultural challenges. In conclusion, the study highlights the significant potential for novel zinc-enriched biochar fertilizers to improve crop micronutrient density. This approach not only addresses the global challenge of micronutrient deficiencies in diets but also offers a sustainable and efficient strategy for resource utilization in agriculture. The experiment thus serves as a valuable model for educational practices, fostering a deeper understanding and practical skills among students in the field of agricultural science. [ABSTRACT FROM AUTHOR]

The present study was carried out to investigate the synergistic and antagonistic interactions of combined application of Phosphorus and Zinc fertilizers on sweet pepper in net house conditions. Pot experiment consists of thirteen treatments combinations set up in a completely randomized design. The treatment combinations comprising of four levels of phosphorus (0, 237.5, 355.5 and 475 kg Single Super Phosphate ha−1) and three levels of Zn (5, 7.5 and 10 kg Zinc Sulfate ha−1) including one control (100% NPK). The available macro and micronutrients content in potting mixture was confirmed in medium range before conducting the experiment. The results clearly demonstrate the treatment comprising 475 kg SSP ha−1 with 10 kg ZnSO4 ha−1 (T13) showed synergistic effects on vegetative characteristics, above and below ground nutrient content as well as nutrient uptake. When balanced phosphatic and zinc fertilizers (T13) are applied to soil, there is a low possibility of an antagonistic reaction. Antagonism problems arise most frequently when the soil's Zn content is extremely low in combination with excess application of P fertilizer limiting their availability to plants. To avoid P-Zn antagonism in the soil system, utilization of appropriate fertilizer methods, supplies, and rates was done. As a result, the present study confirms that recommended fertilizer doses combined with phosphorus @ 475 kg SSP ha−1 and zinc @ 10 kg ZnSO4 ha−1, is the best nutrient combination for improving plant growth parameters; however, in terms of soil parameters, P and Zn fertilizers affected micronutrient content in soil, which further interacted antagonistically. [ABSTRACT FROM AUTHOR]

Background: Salinity stress, an escalating concern in the realm of agriculture, significantly hampers crop productivity worldwide. In recent years, nano‐fertilizers have been identified as an innovative and promising avenue for improving nutrient use efficiency and mitigating salt stress in plants. Aims: This study delves into the comparative efficacy of nano‐fertilizers (Zn and Si) and their conventional sources in bolstering maize's resilience against salt stress. Methods: The hydroponic experiment was conducted to test maize plants under salt stress along with Zn and Si nanoparticles (NPs) application. The analysis extends to their impacts on ionic homeostasis, specifically focusing on potassium and sodium concentrations, K/Na ratio, stomatal conductance, chlorophyll content, and the osmotic potential (OP) within the shoots and roots of maize. Results: Nanoparticles relatively helped plants better under stress, compared to their respective bulk mode of applications. Nano‐Zn treatment considerably boosts the K+ concentration and enhanced K/Na ratio, as a key physiological trait in salt‐resistant species, while nano‐Si demonstrates a prominent role in modulating OP and limiting Na+ accumulation along with higher Zn and Si accumulation in plants. The salt tolerance index confirmed the contribution of these ionic and osmotic adjustments in helping maize plant against salt stress. Conclusions: Our findings confirm that the application of nutrients as nano‐fertilizers, particularly nano‐Zn, enhanced K/Na ratio and improved nutrient availability and uptake of the plant. Si nanoparticles are also attributed to better osmotic adjustment and facilitating water movement, thus highlighting the potential of nano‐fertilizers in improving overall agricultural productivity and related environmental issues. [ABSTRACT FROM AUTHOR]

BACKGROUND AND OBJECTIVES: Zinc deficiency is a significant global health concern, affecting around two billion people due to insufficient dietary intake. The extensive utilization of cereal-based meals with inadequate zinc content and limited bioavailability stands as the primary cause for this issue. Children who possess low levels of zinc experience stunted growth and developmental delays. They also have higher rates of morbidity from pneumonia, diarrhoea, and malaria. Inadequate zinc intake has been correlated with a heightened risk of mortality in children due to specific diseases. It is crucial to secure a satisfactory level of zinc in rice grains because of its indispensable function in various biochemical processes that are fundamental for the growth and advancement of plants. A deficiency in zinc can lead to reduced grain yield and nutritional value in rice. Recently, the utilization of registered biofertilizers and microbial technology is widely recognized in contemporary intensive farming practices. Some indigenous zinc-solubilizing bacterial strains discovered can increase rice yield and zinc content in grains. The objective of this study was to impact of a biofertilizer formula consisting of native zinc solubilizer strains on the growth, productivity, and zinc concentration in the grains of three rice varieties, namely Inpari IR Nutrizinc, Inpari 48, and Inpago 13 Fortiz. The study was conducted in a paddy field located in the Inceptisol of Subang Regency, West Java, during the year 2023. METHODS: The field trial was conducted to study the impact of a biofertilizer comprising a group of non-pathogenic zinc-solubilizing bacteria, including Enterobacter cloacae, Klebsiella pneumoniae, Serratia marcescens, Bacillus thuringiensis, and Enterobacter bugandensis on rice growth, yield, zinc levels, and uptake in grains. The rhizosphere soils were the origin of these bacteria, which were obtained using agar media containing zinc oxide as insoluble zinc compounds. Prior to this, the bacterial strains were evaluated for their capacity to dissolve zinc and generate the plant hormone indole-3-acetic acid. To gauge their zinc-solubilizing prowess, Pikovskaya agar media, supplemented with insoluble zinc oxide and calcium phosphate, respectively, were utilized. The presence of distinct clear areas surrounding the colonies demonstrated the effectiveness of the microbes in converting insoluble zinc and phosphorus into soluble forms. The concentration of the plant hormone indole-3-acetic acid was measured using the Salkowski reagent. The field trial was organized using a split-plot design with three replications. The application of the biofertilizer mixture as a seed treatment was carried out before the transplantation of the rice nursery. The seedlings were prepared individually for each rice variety, with a comparison made between those treated with the biofertilizer and those that were not. FINDINGS: The study found that the consortium of indigenous non-pathogenic zinc-solubilizing bacteria significantly increased the yield of rice varieties by about 5.6 percent and zinc content in grains by 16.3 percent. However, the application of zinc containing fertilizer treatments did not enhance the rice yield and zinc content in grains in this Inceptisol paddy soil. In terms of zinc content in grains, the rice variety Inpago 13 Fortiz exhibited a notable increase compared to the Inpari IR Nutrizinc variety, with levels of 40.3 milligrams per kilogram as opposed to 34.1 milligrams per kilogram. CONCLUSION: the utilization of a native combination of carefully chosen zinc-solubilizing bacterial strains could augment the productivity, zinc concentration, and absorption in rice grains of various varieties in a paddy field with Inceptisols soil type, characterized by a moderate to high overall zinc content and limited zinc accessibility. The addition of zinc containing fertilizer treatments did not enhance rice yield compared to the addition of other tratments or control. This is probably because of the medium-high level of the total zinc content of the soil, suggesting that the addition of Biofertizinc will reduce or delete the crop requirement for zinc fertilizer in Inceptisol paddy fields. This implies that the biofertilizer is ecologically sustainable as it eliminates the use of harmful chemicals, reduces the reliance on synthetic fertilizers, and lowers costs. [ABSTRACT FROM AUTHOR]

In recent years, the increase due to the rise in the high yielding verities led to the high-rate application of chemicals and pesticides in the soil. These chemical fertilizers give great responses to the farmers on a short-term basis, but in the long term, they harm the soil and human health by interfering in the food chain. The use of biofertilizers is a very good alternative for crop production in a sustainable and environment-friendly manner. Numerous bacteria and fungi can be used as biofertilizers for making the essential nutrients available to the plants which are associated with the rhizosphere of different crops, either symbiotically or non-symbiotically. Zinc plays a vital role in crop growth and achieving a great yield among the various macro and micronutrients. Zinc is responsible for Auxin synthesis, chlorophyll formation, protein metabolism, carbohydrate fixation, disease and stress tolerance. Zn deficiency is a global issue that gradually lowers crop output and productivity. Using zinc solubilizing microorganisms is one of the most effective sustainable approaches to achieving higher yield and restoring soil productivity. These microorganisms solubilize the available zinc pool in the soil so plants can easily uptake zinc. Bacillus subtilis, Thiobacillus thioxidans, Rhizobium, Pantoea sp., Gluconacetobacter, Saccharomyces sp. and PGPR (Plant Growth Promoting Rhizobacteria) are involved in zinc solubilizing process and boost the soluble zinc in the soil. Using zinc solubilizers can reduce the fertilizer requirement of the crop to about 25-50% in combination with inorganic zinc fertilizers, so it reduces overall fertilizer cost. [ABSTRACT FROM AUTHOR]

Zinc solubilizing bacteria inhabiting root endosphere possesses great potential to enhance plant yield by solubilizing the nutrients. The potential of Zn solubilizing bacteria Bacillus sp. SH-10 and Bacillus cereus SH-17 to improve yield and grain zinc content of rice was investigated under different regimes of individual and co-inoculation in the presence and absence of chemical fertilizer zinc sulfate (ZnSO4). The strains were applied to the rice varieties basmati 385 and super basmati under field conditions for two consecutive years. A significantly improved growth of rice plants, such as plant height (102–118 cm), number of tillers per plant (8.5–11.5), chlorophyll content (29.5–35.1), zinc requiring enzymes, i.e., superoxide dismutase (396–570 per gram fresh weight (g−1 FW)), carbonic anhydrase activity (CA) (10–15.06 U g−1 FW) and grain yield (3.0–3.8 tons ha−1), was observed in the plants inoculated with Bacillus sp. in the presence of chemical fertilizer (ZnSO4). Consortium of zinc solubilizing bacteria also caused higher grain Zn content (25.0–30.5 mg kg−1) of the rice varieties basmati 385 and super basmati as compared to that of un-inoculated plants. Hence, it can be concluded that Zn solubilizing bacteria has immense potential to be used as agricultural crop inoculants as they synergize the effect of chemical Zn, increase yield and improve the nutritional value of crops. [ABSTRACT FROM AUTHOR]

Zinc (Zn) fertilization of hard red and soft white winter wheat (Triticum aestivum L.) is uncommon in the low precipitation zone of the inland Pacific Northwest. It is uncommon because there have been no indications of deficiency. Soil test data, however, show Zn levels have been declining over time. We conducted a four‐site‐year experiment to evaluate effects of fertilization on early‐season tissue Zn concentration (TZC), dry matter accumulation (DMA), Zn uptake (ZNU), the grain test weight (TWT), protein content (PRO), and yield (YLD) of two regionally adapted cultivars. Planting occurred late in September or early in October. Zinc fertilizer, placed with the seed while planting, was applied at rates of 0 and 5 kg Zn ha−1. Application of 5 kg Zn ha−1 increased TZC and ZNU at one of two sites. There were corresponding trends of increased DMA and improved YLD. Response to fertilization occurred on a relatively shallow soil that had a diethylenetriamine‐pentaacidic acid–extractable Zn test level of 0.3 mg kg−1. Core Ideas: Zinc fertilization increased tissue Zn concentration and Zn uptake in winter wheat (Triticum aestivum L.) at one of two experimental sites.There were corresponding treatment‐induced trends of increased dry matter accumulation and improved grain yield.Response to fertilization occurred on a relatively shallow soil that had a diethylenetriamine‐pentaacidic acid‐extractable soil test Zn level of 0.3 mg kg−1.Response to fertilization may have been due, at least in part, to the near‐surface position of carbonates and alkalinity. [ABSTRACT FROM AUTHOR]

Foliar zinc (Zn) application can affect the accumulation and bioaccessibility of cadmium (Cd) and Zn in crops. However, the mechanisms by which foliar Zn application influences Cd and Zn bioaccessibility remain elusive. This study examined the effects of spraying ZnSO4 and ZnNa2EDTA on bioaccessibility and chemical forms of Cd and Zn in pakchoi (Brassica chinensis L.) shoots and evaluated human health risks via pakchoi consumption. Spraying ZnSO4 reduced the concentrations of ethanol-extractable (Fethanol) and deionized water-extractable (Fd-H2O) Cd, as well as the corresponding bioaccessible Cd concentrations (20.3–66.4%) and attendant health risks of Cd, whereas spraying high-dose ZnNa2EDTA significantly increased the concentrations of both Cd forms and bioaccessible Cd. Spraying ZnSO4 and high-dose ZnNa2EDTA significantly increased the concentrations of Zn in Fethanol and Fd-H2O and the corresponding bioaccessible Zn concentrations (0.8–8.3-fold). Fethanol and Fd-H2O were the primary sources of bioaccessible Cd and Zn, contributing more than 59% of the bioaccessible Cd and Zn. These results indicate that foliar Zn application can affect Cd and Zn bioaccessibility in pakchoi mainly by modulating Cd and Zn in Fethanol and Fd-H2O. These findings provide scientific support for the development of more efficient measures to produce safe and high-quality leafy vegetables from Cd-polluted soils. [ABSTRACT FROM AUTHOR]

Zinc (Zn) is an essential micronutrient that participates in several plant metabolisms. Soil application of Zn is an effective strategy to increase the productivity and Zn concentration in maize grains, but the effect of Zn fertilizers on the nutrients uptake and biofortification still needs more studies. In this study, a greenhouse plot experiment was conducted to evaluate the effect of the optimum Zn fertilizer doses (0, 5.7, and 11.4 kg ha−1) on the nutrients uptake and Zn biofortification of maize crops. Zn applications were found to increase significantly the transpiration rate; photosynthesis rate, Zn, and P concentration in the maize shoot at the VT (Tasseling) stage as well as the grain Zn and maize grain yield. P, Mg, and phytic acid (PA) concentration in grains was also increased with a Zn application of 11.4 kg ha−1. The PA/Zn molar ratio in grains decreased due to the Zn application doses as compared with the control treatment, but there was no significant difference between Zn 5.7 and 11.4 kg ha−1 doses, while Zn 5.7 kg ha−1 achieved a higher PA/Fe molar ratio in maize grains compared to other treatments. [ABSTRACT FROM AUTHOR]

During the two successive summer seasons of 2022 and 2023, two field experiments were performed in the experimental farm of the faculty of Agriculture, Zagazig University, Egypt, to investigate the effectiveness of phosphoric fertilizer levels and zinc foliar application timeon yield, yield attributes and quality of peanut/ groundnut seeds. Split plot design was used laying out P levels in main plots and allocating Znapplication timein the sub plots.Results exhibited the operative effects of Plevels on pod and seed numbers and weights. The uppermost pod number and weight/plant were the resultant of supplying 23.25 kg P2O5/fad. Zn application at pegging was conjoint with noteworthy increase for both seed number and weight/plant. Early application of Zn(35 days after sowing, 35 DAS) increased pigged flowers, while late application (65 DAS) promoted seed weight/plant. Yields of pods, seeds and the biological one besides the harvest index were sensibly affected ascribed to the treatments of P levels and Zn supply. Phosphorus levels affected vegetative growth efficiency, while the moderate P level (32.25 kg P2O5/fad.) has intrinsically influenced on peanut yield attributes and enhanced pod number and weight/plant, seed weight/plant as well as 100 seed weight. Zinc application time affected pod and seed yields. The interaction between P levels and and time of Zn application was significant, with seed yield being the decisive factor. Oil percentage is a varietal property, with Zn application time and P levels not significantly affecting seed content. Seed protein content was significantly different, with Zn being the substantial factor affecting protein content.P-uptake (PU) and nitrogen use efficiency (NUE) in peanut plants were significantly inverse affected by P levels and Zn application time. It is recommended to supply phosphorusat 23.25 P2O5 kg/fad., and apply Zinc 50 DAS at pegging face for affluence yields and high quality. [ABSTRACT FROM AUTHOR]

Zinc (Zn) deficiency is a major public health issue worldwide. The biofortification of Zn in popular vegetables could be a promising way to address this burning issue. To enrich tomatoes with bioavailable Zinc through agronomic biofortification. Seven tomato varieties were examined to identify the best one for Zn biofortification based on fruit Zn concentrations. Then six levels of Zn viz., 0, 2, 3, 4, 5, and 6 kg ha−1 were applied to screen out the best Zn dose for maximum biofortification. Finally, the identified Zn dose was applied using six strategies viz., 100% seedling priming, 50% soil + 50% foliar spray at seedling stage, 50% seedling priming + 50% foliar spray, 100% foliar spray at seedling stage, 100% foliar spray at flowering stage and 100% foliar spray at the fruiting stage to recognize the best application strategy. These three experiments were executed following a completely randomized design with three replications. In screening, BARI Tomato-14 showed the lowest Zn concentration compared to all other varieties. The application of 5 kg Zn ha−1 showed the highest Zn concentration in tomato with better yield and quality. Finally, 5 kg Zn ha−1 as 50% soil application + 50% foliar spray showed the maximum biofortification of Zn in BARI Tomato-14 with the highest growth, yield and quality. Therefore, application of 5 kg Zn ha−1 as 50% soil and 50% foliar spray on BARI tomato-14 could be a potential option to mitigate Zn deficiency. [ABSTRACT FROM AUTHOR]

Onions, a crucial bulb crop cultivated globally, including in Ethiopia, face significant production challenges. These constraints encompass poor soil fertility, inappropriate fertilizer usage, limited availability of improved varieties, disease and insect pests, and the high costs associated with commercial fertilizers. Among these limitations, improper fertilizer application amounts and types play a pivotal role in restricting onion production. To address this, a field experiment was conducted during the 2020-2021 cropping season in the Shewa Robit district of the North Shewa zone. The study assessed the impact of NPS and Zn fertilizer rates on onion growth and yield. The treatments included four NPS fertilizer rates (0, 121, 242, and 363 kg/ha) and four levels of ZnSO4 (0, 0.25, 0.5, and 0.75% w/v). The experiment was laid out as a randomized complete block design in a factorial arrangement and replicated three times. The results demonstrated that the interaction effect of NPS and Zn fertilizers significantly influenced various onion parameters, including days to maturity, plant height, leaf length, marketable bulb yield, unmarketable bulb yield, and total bulb yield. The application of NPS at a rate of 242 kg/ha and 0.75% ZnSO4 led to the highest plant height (65.20 cm), leaf length (51.93 cm), marketable bulb yield (34.87 t/ha), and total bulb yield (35.04 t/ha). In addition, this treatment combination yielded the highest net benefit (908,628.89 ETB/ha) with an acceptable MRR (313.64%) compared to other treatments. Hence, it can be recommended for economical production of onion in the study area and areas with similar agroecologies. [ABSTRACT FROM AUTHOR]

Background and aims: Zinc (Zn) deficiency is widespread in citrus orchard around the world, which impairs plant growth and fruit yield. Zn fertilization is usually recommended in field orchards, and application strategies toward nutrient use efficiency are key for successful crop management. Methods: Field studies were carried out with sweet orange trees for four growing seasons, testing Zn (nitrate, sulfate or EDTA) applied either via fertigation or foliar spray compared to a control without Zn. Results: The Zn concentrations in the soil increased with nutrient supply by both application methods. Zn-EDTA via fertigation increased soil nutrient availability compared to the control. Likewise, Zn-nitrate via foliar application also increased soil Zn levels. Regarding the plant, Zn-EDTA via fertigation increased leaf nutrient levels only after the third year of fertilization, whereas Zn-nitrate via foliar spray increased leaf levels in the short term, up to 120 mg kg−1. To a lesser extent, Zn-EDTA or sulfate also increased leaf Zn compared to the control. Accumulated fruit yield was ~20% higher in trees with Zn-EDTA via fertigation and ~ 20% higher in trees with Zn-nitrate or sulfate via foliar application compared to the control, with these latter exerting greater responses. Trees supplied with Zn exhibited lower H2O2 and higher CAT activity compared to the control, which correlated with a fruit yield increase. Conclusion: In conclusion, Zn-EDTA via fertigation or nitrate or sulfate via foliar application improved the horticultural performance of trees, supporting the establishment of best nutrient management practices in fruit production. [ABSTRACT FROM AUTHOR]

Wheat stands as a cornerstone of global food security. To increase its productivity as well as quality, nutrient management is one of the most important factors. To evaluate the potential contribution of micronutrients to enhancing wheat yield, an experiment was conducted to investigate the interactive effect of zinc and copper on yield and quality indicators (protein, sedimentation value) of wheat under manganese-deficient and sufficient soils in potted plants during the rabi season 2020-21. The experiment was laid out in CRD with three replications and treatments comprised of Zn and Cu levels each @ 0, 2.5, 5.0, 7.5, and 10.0 mg kg-1 applied through ZnSO4 & CuSO4. The results revealed a significant increase in both grain and straw yield, as well as the quality of wheat over their respective control with the application of Zn and Cu. The highest wheat grain yield (6.24 g per pot) was achieved in soils with sufficient Mn when treated with Zn at 10.0 mg kg-1 and Cu at 10.0 mg kg-1. It was further observed that the significant increase in protein content was noticed only up to Cu7.5 when compared with Cu2.5 and a further increase in Cu level from Cu7.5 to Cu10.0 did not affect the protein content significantly in Mn-sufficient soil. The treatments with the best economic aspect were found 5.0 mg kg-1 of zinc sulfate x 7.5 mg kg-1 of copper sulfate, in terms of using less zinc and copper fertilizers and having a favorable impact on the attributes. In conclusion, the application of micronutrients like Zn and Cu should be considered an integral part of a holistic nutritional approach to support optimal wheat growth and its quality. This approach enables farmers to achieve the highest potential yield and quality in their wheat crops. [ABSTRACT FROM AUTHOR]

A 2-year crop rotation study in southern Manitoba assessed the effects of starter fertilizer on grain corn (Zea mays L.) production when corn followed canola (Brassica napus L.) versus soybean (Glycine max L. Merr.). Treatments included a control (no starter) and two rates of phosphorus (P) (30 and 60 kg P2O5 ha−1) as monoammonium phosphate (MAP, 11–52–0) or MicroEssentials® SZ (MESZn, 12–40–0–10–1) side-banded at planting. The preceding crop did not have any influence on mycorrhizal colonization of corn roots at the V4 corn growth stage. However, side-banded fertilizer increased early-season biomass by as much as 111% compared to the unfertilized control, averaged across all site-years, with the largest increases occurring where corn followed canola. P concentration and uptake in early-season biomass increased as the P rate increased. Zinc (Zn) concentrations in early-season biomass were the greatest for the unfertilized control and MESZn treatments, while Zn uptake was significantly greater with the application of starter fertilizer compared to the unfertilized control. Starter P advanced silking date by 2–7 days relative to the unfertilized control. At maturity, starter P reduced grain moisture by 21–27 g kg−1 in corn only after canola. The high rate of MAP increased grain yield by an average of 770 kg ha−1 compared to the unfertilized control, regardless of the preceding crop. The negative influence of the preceding canola crop on early-season growth and mid-season development of corn can be managed with starter fertilization to provide adequate P and Zn to the corn crop and maintain successful production in Manitoba. [ABSTRACT FROM AUTHOR]

Peanut has a fairly strong ability of accumulating cadmium (Cd) from the soil, and the problem of Cd content in peanut exceeding the food safety standard is serious in some regions of China. Seed coating is a common technology to control diseases and insect pests and enhance stress resistance in peanut production, but the research of using seed coating technology to control Cd pollution risk in peanut producing areas has not been reported. This study first screened out three suitable concentrations of manganese (Mn) and zinc (Zn) coating agents by seed germination test, and then further screened out the concentration of coating agent with the best Cd reduction effect by pot experiment. The effect of Mn fertilizer and Zn fertilizer seed coating on Cd transfer within peanut plant in Cd-contaminated soil was further explored through pot experiment. The results of seed germination test showed that the seed coating treatment with low to moderate concentrations of Mn and Zn fertilizer did not affect the seed germination rate and could promote the root length, while the excessive concentration could obviously inhibit the seed germination. The results of pot experiment showed that among the seed coating agents of Mn and Zn, 3% Mn fertilizer coating agent (Mn3) and 2% Zn fertilizer coating agent (Zn2) had the most significant effect on reducing Cd in peanut seeds, with the Cd reduction rates reaching 19.0% and 24.1% respectively, and Zn2 had the better Cd reduction effect. Compared with the control, the Cd bioaccumulation factor of roots in the two treatments decreased significantly, the Cd translocation factor (TF) from roots to shoots increased significantly, the TF from shoots to seeds decreased, while the TF from roots to seeds had no obvious change. Compared with the control, the absorption of Cd in peanut plants under Mn3 and Zn2 treatments decreased by 9.18% and 13.6%. There was a significant negative correlation between the contents of Cd in peanut seeds and roots and the contents of Mn and Zn in roots. Seed coating with Mn and Zn can reduce the Cd content in peanut seeds by inhibiting the absorption of Cd by roots and the transport of Cd within peanut plant. This study put forward the technology of reducing Cd content in peanut by seed coating, which provided a new method for risk control of Cd pollution in peanut producing areas. Key words: seed coating; seed germination; peanut; cadmium ble sugar decreased after PS-NPs exposure. Transcriptome analysis showed that a total of 2112 differentially expressed genes were generated by PS-NPs exposure treatment, GO and KEGG analysis showed that they were mainly enriched in pathways related to redox reaction, reaction to ethylene and abscisic acid, amino acid metabolism and synthesis of other secondary metabolites. It was noted that 250 transcription factors were differentially expressed, mainly including the ERF, WRKY, NAC, bHLH and MYB transcription factor families. This experiment lays a foundation for further exploring the impact of nanoplastics on crops such as soybeans and its molecular mechanism. [ABSTRACT FROM AUTHOR]

Background: Precipitation of Zn phosphates may limit Zn availability in cogranulated P fertilizers. We assessed whether the Zn availability of Zn could be improved by post-granulation acid treatment. Methods: Uncoated Zn-fortified monoammonium phosphate granules were compared with sulfuric acid-coated granules in which Zn was either cogranulated or dissolved in the acid coating. Spatially resolved XRF and XANES was used to assess the distribution and speciation of Zn in the granules (before and after incubation in soil) and in the exposed soil. The amount of Zn remaining in the granule was determined after incubation in various soils. The effect of acid coating rate on corn yield was determined in a highly Zn-deficient soil in a pot trial. Results: The speciation of Zn in the untreated granules was dominated by Zn phosphates. In the sulfuric acid treatments, sulfate species accounted for ~ 45% (if cogranulated) or ~ 80% (if coated) of the Zn. After one week incubation in soil, 10–86% of the added Zn remained in the residual granule, mostly as sparingly soluble compounds. The Zn speciation in the soil near the granule was dominated by Zn phosphates irrespective of treatment, but Zn moved further away from the application site in the acid treatments, as more Zn was released from the granule. In the pot trial, the dry matter yield increased by 70% at a coating rate of 0.75% H2SO4 compared to the uncoated control. Conclusions: Post-granulation acid treatment of Zn-fortified P fertilizers is an effective way to enhance the phytoavailability of fertilizer Zn. [ABSTRACT FROM AUTHOR]

[Objective] This study explored the effects of different zinc fertilizer application methods on photosynthetic characteristics, quality and economic benefits of apple to provide reference for rational application of zinc fertilizer in apple. [Method] In Pucheng and Qianxian, Shaanxi, "Changfu No.2" apple was elected for three treatments of no zinc application (control, T1), leaf spraying zinc fertilizer (T2) and integrated water and fertilizer topdressing zinc fertilizer (T3). Soil available zinc content, apple fruit and leaf zinc contents, leaf biological characters, yield, quality and economic benefit were determined under different treatments. [Result] In Qianxian and Pucheng, contents of available zinc in T2 and T3 treatments were higher than that in T1 treatment in soil layers of 0 - 20 and 20 - 40 cm. T3 treatment had the highest values of 1.88 and 1.22 mg/kg in soil layer of 0 - 20 cm and 1.16 and 0.70 mg/kg in soil layer of 20 - 40 cm. In Qianxian, zinc contents of leaves and fruits under T2 treatment were the highest, followed by T3 treatment. In Pucheng, zinc contents in leaves and fruits of T2 and T3 treatments were higher than that of T1 treatment, with the highest values in T3 treatment. In Qianxian and Pucheng, louver thickness, louver weight and chlorophyll content in T2 and T3 treatments were significantly increased compared with T1 treatment. In Qianxian, the fruit shape index of apples was 0.83 - 0.89, with significantly higher values in T1 treatment. In Pucheng, the fruit shape index of apples ranged from 0.81 to 0.91, and T3 had higher values than T1 and T2 treatments. In Pucheng, there was no significant differences in soluble solids and titratable acid contents among treatments. In Qianxian county, the titratable acid content of T2 and T3 treatment was significantly higher than that of T1 treatment, and there was no significant differences in soluble solids among treatments. In Qianxian and Pucheng, contents of soluble sugar and Vc in T2 and T3 treatments were significantly higher than those in T1 treatment. In Qianxian, the highest apple yield and net profit were 30 961 kg/hm² and 82 505 yuan/hm² in T2 treatment, which were increased by 45.49% and 2.85% compared with T1 treatment. The yield and net profit of T3 in Pucheng were the highest, which were 29 159 kg/hm² and 78 595 yuan/hm² and were increased by 28.56% and 65.77% compared with T1 treatment, respectively. [Conclusion] Application of zinc fertilizer improved contents of zinc in soil, apple eaves and fruit, as well as the yield and quality of apple. From the perspective of yield and economic benefits, he effect of water and fertilizer combined application of zinc fertilizer was more stable than that of foliar spraying. [ABSTRACT FROM AUTHOR]

This study examined how silicon and zinc fertilizers affect the quality and aroma of Nanjing 46. We applied nine different fertilizer treatments, one involving soil topdressing at the top fourth leaf-age stage and one involving foliar spraying during the booting stage of the silicon and zinc fertilizers. We tested the effects of the nine treatments on grain quality and aroma. Silicon and zinc fertilizers significantly affected the brown rice rate, milled rice rate, head rice rate, amylose content, gel consistency, RVA characteristic value, taste value, and aroma but did not affect the chalky grain rate, chalkiness, protein content, rice appearance, hardness, stickiness, balance, peak time, or pasting temperature. Silicon fertilizer decreased the rate of brown rice and milled rice, whereas zinc fertilizer increased the rate of brown rice and milled rice. Silicon and zinc fertilizers improved the head rice rate. Compared to silicon fertilizer, the impact of zinc fertilizer on increasing the head rice rate was more pronounced. Although the effects of silicon and zinc fertilizers on the amylose content and RVA characteristic value varied depending on the treatment, their application could lower the amylose content, increase gel consistency, improve breakdown viscosity, decrease setback viscosity, increase aroma, and improve the taste value of rice. [ABSTRACT FROM AUTHOR]

Water stress poses a significant challenge for plant growth and productivity, impacting both yield and quality. With the ongoing changes in global climate, mitigating the adverse effects of water deficiency on plants has become crucial. In this study, the focus is on enhancing the tolerance of Ocimum basilicum L., a plant highly susceptible to water stress. To achieve this, in this study examined the effects of zinc fertilizer supplementation at varying rates (2.5 - 5 and 10 mg/kg) on O. basilicum grown in silty sandy soil and subjected to water stress conditions. Several parameters, including mineral uptake, morphological characteristics, total phenol and flavonoid contents, and essential oil compounds, were evaluated in sweet basil. The results revealed that water stress had a detrimental impact on the morphological properties and secondary metabolites analysed. Estragole emerged as the main compound in the essential oil analysis, with the highest concentration (69.37%) observed in the group treated with 10 mg/kg of zinc fertilizer. Conversely, the lowest concentration (66.14%) was recorded in the water-stressed group without fertilizer. Notably, the application of zinc fertilizer at concentrations of 5 and 10 mg/kg significantly ameliorated the negative effects induced by water stress. Furthermore, zinc exhibited diverse mechanisms of action concerning the uptake of other nutrients from the soil. [ABSTRACT FROM AUTHOR]

Acanthopanax senticosus (Rupr. et Maxim.) Harms is a perennial shrub of the Acanthopanax genus in the Araliaceae family and has a high medicinal value. The application of zinc fertilizer can improve the yield and quality of medicinal materials. However, there are limited reports on approaches to increase the content of medicinal components in A. senticosus, hindering the improvement of its medicinal quality. In this study, A. senticosus was treated with 0.1% (LZn) and 0.4% (HZn) zinc sprayed on the leaf surface. The effects of zinc treatment on the medicinal components in the roots of A. senticosus were analyzed by comprehensive metabolomics and transcriptomics analyses. A total of 316 metabolites were detected, with a prevailing occurrence of terpenoids and phenylpropanoids. We identified metabolites related to the medicinal components that were upregulated after Zn treatment, including 43 terpenoids, 19 phenylpropanoids, eight phenols, and three flavonoids. Combining differential gene expression and K-means analysis, we found 95, 65, and 25 upregulated genes related to phenylpropanoid biosynthesis, terpenoid biosynthesis, and flavonoid biosynthesis, respectively. Under different concentrations of Zn treatment, the upregulated metabolite biosynthesis-related genes and differentially expressed transcription factors varied. Pearson correlation network analysis revealed significant correlations among terpenoids, phenylpropanoids, flavonoids biosynthetic genes, and several transcription factors (ERFs, WRKYs, bHLHs, NACs, and MYBs). This study lays the foundation for understanding the metabolic processes in response to varying levels of zinc foliar spray and provides a theoretical basis for enhancing the efficiency of zinc fertilizer utilization in A. senticosus. [ABSTRACT FROM AUTHOR]

Groundwater monitoring is critically important, even though it is costly and often neglected. In this study, a judgmental monitoring of groundwater offering solutions based on a cost and time-effective research approach is presented. The method was performed in three Mediterranean areas in Greece and Italy to examine its advantages and disadvantages. As a first step, a multi-statistical analysis was practiced to assess and apportion the potential contributions of pollution sources of groundwater. Pearson correlation, principal component analysis, and factor analysis were applied to groundwater samples to characterize the evolution of hydrochemical processes. High concentrations of chlorides and nitrates highlight that salinization and the extensive use of nitrate fertilizers dominate in the coastal part of Eastern Thermaikos Gulf, the dissolution of carbonate rocks and livestock/industrial activities drive the groundwater quality status in the Upper Volturno basin, while in the Mouriki basin thermal power plant and the use of zinc fertilizers are the main factors of groundwater quality degradation. The determination of the critical sampling points was applied, considering the land use and hydrogeological and morphological characteristics of the areas. The application of the judgmental sampling approach provides reliable results regarding groundwater evolution. These results were compared to previous works and found that a non-probability sampling technique can provide the same results as a more costly method in the Mediterranean region. Thus, judgmental sampling is crucial for the optimal application of water resource management and control techniques in basins to avoid gaps in data collection. [ABSTRACT FROM AUTHOR]

During the summer and rainy seasons (April-October) of 2020 and 2021, two consecutive field experiments were conducted at the research farm of the ICARIndian Agricultural Research Institute, New Delhi, India. In this study, we examined the effects of summer green manuring crops (GM) and a variety of zinc fertilizers (ZnF) on Basmati rice (Oryza sativa L.) growth, physiological development, yield response, zinc nutrition and economic returns. A combination of GM residues and nano zinc fertilization helped significantly enhancing Basmati rice’s growth and its physiological development. Following the incorporation of Sesbania aculeata (Sesbania), successive Basmati rice physiological parameters were significantly improved, as well as grain, straw, biological yields, harvest index and economic returns. The highest Zn content of 15.1 mg kg-1 and the lowest of 11.8 mg kg -1 in milled rice grain were recorded in Sesbania green manuring (G2) and control i.e., in the fallow (G1), respectively. Coating onto urea with 0.2% nano zinc oxide (NZnCU) was observed to be more effective than other zinc sources in terms of growth parameters, yield attributes, zinc nutrition, grain and straw yields for succeeding Basmati rice crop; however, the effects were comparable to those of bulk zinc oxide-coated urea (BZnCU) of 1%. The highest Zn content of 15.1 mg kg -1 was recorded with the application of 1% BZnCU and the lowest of 11.96 mg kg -1 with the soil application of 5 kg Zn ha -1 through bulk ZnO in the milled rice grain. Application of 1% BZnCU led to a 26.25% increase in Zn content of milled rice grain compared to soil application of 5 kg Zn ha -1 through bulk ZnO. As a result, the combination of inclusion of Sesbania aculeata (Sesbania) residue and 0.2% NZnCU was identified as the most effective treatment, for Basmati rice growth and physiological development. A combination of nano Zn fertilization in conjunction with the incorporation of green manure can be advocated for better growth, physiological performance, zinc dense grains, and higher profitability of Basmati rice for farmers and consumers. [ABSTRACT FROM AUTHOR]

Trace elements play a crucial role in the growth and bioactive substance content of medicinal plants, but their utilization efficiency in soil is often low. In this study, soil and Aconitum carmichaelii samples were collected and measured from 22 different locations, followed by an analysis of the relationship between trace elements and the yield and alkaloid content of the plants. The results indicated a significant positive correlation between zinc, trace elements in the soil, and the yield and alkaloid content of A. carmichaelii. Subsequent treatment of A. carmichaelii with both bulk zinc oxide (ZnO) and zinc oxide nanoparticles (ZnO NPs) demonstrated that the use of ZnO NPs significantly enhanced plant growth and monoester-type alkaloid content. To elucidate the underlying mechanisms responsible for these effects, metabolomic analysis was performed, resulting in the identification of 38 differentially expressed metabolites in eight metabolic pathways between the two treatments. Additionally, significant differences were observed in the rhizosphere bacterial communities, with Bacteroidota and Actinobacteriota identified as valuable biomarkers for ZnO NP treatment. Co-variation analysis further revealed significant correlations between specific microbial communities and metabolite expression levels. These findings provide compelling evidence that nanoscale zinc exhibits much higher utilization efficiency compared to traditional zinc fertilizer. [ABSTRACT FROM AUTHOR]

The application of zinc fertilizers in the soil has been an agronomic practice to correct Zn deficiency in plants, aiming to increase productivity and/or nutritional quality. This study evaluated how zinc sulfate fertilization affects plant growth, yield performance and nutrient accumulation in the cassava 'IAC 576-70'. The experimental design was in randomized blocks with eight replications. The treatments consisted of 0, 1.5, 3.0, 4.5 and 6.0 g p1-1 ZnSO4. Results showed improvement in yield with soil fertilization with ZnSO4, with the optimal dose of 2.5 g pl-1. The uptake of nutrients in plant parts is favored with lower doses of zinc fertilizer, with maximum points ranging from 0.8 to 3.2 g pl-1 for macronutrients and 1.6 to 3.6 g pl-1 for micronutrients. The Zn content in tuberous roots increases by more than 40% with fertilization up to 2.8 g pl-1 of fertilizer, which contributes to the nutritional value of roots. [ABSTRACT FROM AUTHOR]

The effect of nitrogen and zinc treatment on quality and yield was studied to provide a theoretical basis for generating high-quality and high-yielding foxtail millet. In the years 2021–2022, 'Jingu 21' was utilized as the test material in a split-plot design. The main plot was subjected to nitrogen treatment, while the sub-plot was treated with zinc. An arrangement of random blocks was employed. Four levels of nitrogen application (0 kg/hm2, 120 kg/hm2, 180 kg/hm2, 240 kg/hm2) and three levels of zinc application (20 mg/L, 40 mg/L, 80 mg/L foliar spraying) were set, resulting in a total of twelve treatments. Each treatment was replicated three times, with each plot covering an area of 15 m2. (1) The findings indicated that the contents of crude fat and crude protein in foxtail millet increased initially and then decreased with the increase in nitrogen application concentration. Additionally, the protein components were found to be in the following order: gliadin > albumin > glutenin > globulin. (2) Adding an appropriate amount of nitrogen fertilizer under the same zinc level promoted the contents of amylose, total carotenoids, and flavonoids in millet to some extent. Over the course of two years, the content of flavonoids in millet was highest when treated with N180Zn40 (nitrogen 180 kg/hm2, zinc 40 mg/L), showing an increase of 50.14% and 58.67%, respectively, compared to the treatment of applying zinc fertilizer alone at the same zinc level. (3) The phytic acid content and phytic acid/zinc molar ratio exhibited a pattern of initially decreasing and then increasing with the rise in nitrogen and zinc concentrations. (4) The application of zinc fertilizer and increased nitrogen fertilizer for two consecutive years had a significant impact on the yield of millet. Additionally, the application of zinc fertilizer had a highly significant effect on both the ear weights and thousand-kernel weights of millet (p < 0.001). The results demonstrated a positive synergistic effect when nitrogen fertilizer and zinc fertilizer were applied together. This combination significantly improved millet yield and thousand-kernel weights, enhanced the nutritional quality, and increased the content of functional components. Additionally, it also improved the availability of zinc. [ABSTRACT FROM AUTHOR]

The search for an effective zinc fertilizer and its application method to effectively increase zinc content and enhance aroma in rice grains is a crucial objective. In this study, a 2-year field plot experiment was conducted to investigate the influence of ZnO NPs foliar spraying on rice quality, grain zinc and aroma content, along with exploring the physiological mechanisms underlying these effects. Our results demonstrated that the rice breakdown value and taste value of foliar spraying zinc oxide nanoparticles were improved by 31.0–41.7% and 8.2–13.0% compared with CK (control treatment involved spraying water), improving the tasting and steaming quality of rice. While Fe and Cu content in grains decreased for the application of zinc oxide nanoparticles, zinc oxide nanoparticles foliar spraying significantly increased the zinc content and accumulation of grains by 33.6–65.1% and 37.8–74.7%, respectively. Further analysis showed that the sprayed zinc oxide nanoparticles achieved effective enrichment of zinc in edible parts and increased the final bioavailability of Zn. In addition, foliar spraying of zinc oxide nanoparticles significantly increased activities of nitrate reductase and glutamine synthetase in leaves, which elevated nitrogen content in leaves and grains, and ultimately enhanced 2-acetyl-1-pyrroline (2-AP) content in grains at maturity by 6.1–21.4% compared to CK. Our findings indicated that zinc oxide nanoparticles can be practically applied as a foliar fertilizer at the gestation for quality improvement, zinc enrichment and aroma enhancement of rice grains. [ABSTRACT FROM AUTHOR]

Micronutrient deficiency is a serious health issue in resource-poor human populations worldwide, which is responsible for the death of millions of women and underage children in most developing countries. Zinc (Zn) malnutrition in middle- and lower-class families is rampant when daily calorie intake of staple cereals contains extremely low concentrations of micronutrients, especially Zn and Fe. Looking at the importance of the problem, the present investigation aimed to enhance the growth, yield, nutrient status, and biofortification of wheat crop by inoculation of native zinc-solubilizing Bacillus spp. in conjunction with soil-applied fertilizers (NPK) and zinc phosphate in saline soil. In this study, 175 bacterial isolates were recovered from the rhizosphere of wheat grown in the eastern parts of the Indo-Gangetic Plain of India. These isolates were further screened for Zn solubilization potential using sparingly insoluble zinc carbonate (ZnCO3), zinc oxide (ZnO), and zinc phosphate {Zn3(PO4)2} as a source of Zn under in vitro conditions. Of 175 bacterial isolates, 42 were found to solubilize either one or two or all the three insoluble Zn compounds, and subsequently, these isolates were identified based on 16S rRNA gene sequences. Based on zone halo diameter, solubilization efficiency, and amount of solubilized zinc, six potential bacterial strains, i.e., Bacillus altitudinis AJW-3, B. subtilis ABW-30, B. megaterium CHW-22, B. licheniformis MJW-38, Brevibacillus borstelensis CHW-2, and B. xiamenensis BLW-7, were further shortlisted for pot- and field-level evaluation in wheat crop. The results of the present investigation clearly indicated that these inoculants not only increase plant growth but also enhance the yield and yield attributes. Furthermore, bacterial inoculation also enhanced available nutrients andmicrobial activity in the wheat rhizosphere under pot experiments. It was observed that the application of B. megaterium CHW-22 significantly increased the Zn content in wheat strawand grains along with other nutrients (N, P, K, Fe, Cu, andMn) followed by B. licheniformis MJW-38 as compared to other inoculants. By and large, similar observations were recorded under field conditions. Interestingly, when comparing the nutrient use efficiency (NUE) of wheat, bacterial inoculants showed their potential in enhancing the NUE in a greater way, which was further confirmedby correlation and principal component analyses. This study apparently provides evidence of Zn biofortification in wheat upon bacterial inoculation in conjunction with chemical fertilizers and zinc phosphate in degraded soil under both nethouse and field conditions. [ABSTRACT FROM AUTHOR]

The growth and productivity of wheat crops depend on the availability of essential nutrients such as zinc (Zn) and potassium (K2O), which play critical roles in the plant's physiological and biochemical processes. This study aimed to investigate the synergizing effect of zinc and potassium fertilizers on uptake of both the nutrients, growth, yield, and quality of the Hashim-08 cultivar and local landrace, during the 2019–2020 growing season in Dera Ismail Khan, Pakistan. The experiment was designed using a split plot pattern in a randomized complete pattern, with main plots for the wheat cultivars and subplots for the fertilizer treatments. Results indicated that both cultivars responded positively to the fertilizer treatments, with the local landrace exhibiting maximum plant height and biological yield, and improved Hashim-08, showing increased agronomic parameters, including the number of tillers and grains and spike length. Application of Zn and K2O fertilizers significantly enhanced agronomic parameters, such as the number of grains per plant, spike length, thousand-grain weight, grain yield, harvest index, Zn uptake of grain, dry gluten content, and grain moisture content, while crude protein and grain potassium remained relatively unchanged. The soil's Zn and K content dynamics were found to vary among treatments. In conclusion, the combined application of Zn and K2O fertilizers proved beneficial in improving the growth, yield, and quality of wheat crops, with the local landrace exhibiting lower grain yield but greater Zn uptake through fertilizer application. The study's findings highlight that the local landrace showed good response to the growth and qualitative parameter when compared with the Hashim-08 cultivar. Additionally, the combined application of Zn and K showed a positive relation in terms of nutrient uptake and soil Zn and K content. [ABSTRACT FROM AUTHOR]

Nano-fertilizer has been dubbed 'the fertilizer of the 21st century', and it is already being used extensively in agriculture. Zinc oxide nanoparticles (ZnO-NPs) have excellent biological properties and are expected to be an ideal choice for plant zinc fertilizer. Tea is one of the top three beverages in the world, and improving the quality of tea is a priority in its research field. In this study, different concentrations (0, 10, 50, 100, 150, and 200 mg·L−1) of ZnO-NPs were sprayed on tea leaves to investigate their effects on volatile aroma substances and biochemical aspects of tea leaves. The results revealed that various concentrations of ZnO-NPs had different effects on physiological indexes. The concentration of 150 mg·L−1 of ZnO-NPs enhanced chlorophyll content, while the 100 mg·L−1 concentration of ZnO-NPs promoted the accumulation of soluble proteins and the activity of antioxidant enzymes, including a decrease in the content of malondialdehyde. In addition, the ZnO-NPs spray reduced the content of tea polyphenols. A total of 27 volatiles were identified under six treatments, with benzene being the common compound with an average content of 45.97%. Ethanolamine and cis-3-hexenyl acetate were the other two major compounds. It was concluded that the presence of ZnO-NPs improved the antioxidant system of teas, increased soluble protein content and provided better reactive oxygen species protection for plants, especially in the case of ZnO-NPs at 100 mg·L−1. We highlighted that ZnO-NPs application was a favorable way to improve tea trees growth. [ABSTRACT FROM AUTHOR]

Integrated nutrient management is one of the most effective techniques to tackle soil fertility concerns and boost crop productivity. Taking this into consideration, a pot experiment was carried out to determine the effects of selected organic amendments and zinc (Zn) fertilizer on the soil quality, Zn uptake, growth, and yield of maize (Zea mays L.). Fifteen treatments containing different combinations of three organic sources comprising of compost (5 ton/ha), bioslurry (10 ton/ha), farmyard manure (10 ton/ha), and a Zn sulfate (6 kg of Zn/ha) fertilizer as an inorganic source were employed. The individual and combined application of compost, bioslurry, farmyard manure, and Zn sulfate significantly and positively affected the soil chemical properties, nutrient uptake, physiology, growth, and yield attributes of maize. Interestingly, the co-addition of bioslurry and compost with Zn sulfate was the most effective treatment that significantly increased the seed germination (75%), plant physiology (72–96%), shoot and root lengths (68–82%), shoot fresh and dry weights (66–65%) and root fresh and dry weights (84–86%), 1000-grain weight (91%), and Zn in grain (71%) as compared to their respective controls. Furthermore, the co-application of bioslurry and compost with Zn sulfate considerably improved the soil quality attributes (62–87%). The findings of the current study imply that combining compost and bioslurry with Zn fertilizer could be a useful strategy for improving soil quality, Zn uptake and accumulation in grains, and the overall quality and productivity of maize crops. [ABSTRACT FROM AUTHOR]

A field experiment was conducted in Al-Muthanna Governorate on the banks of the Al-Suwer River in Iraq in the spring of 2017. The objective of this study was to know the effect of adding humic and fulvic fertilizers and zinc sulfate fertilizers on the availability of zinc and phosphorous in the soil and plants and the yield of maize crops. Four treatments of humic and fulvic fertilizers were used: Without adding acid (H0), spraying at a concentration of 10 mL/L after 40 and 80 days of planting (H1), soaking the seeds at a concentration of 20 mL/L24 h before planting (H2), and soaking seeds at a concentration of 20 mL/Lplus spraying at a concentration of 10 mL/L(H3). Furthermore, three levels of zinc sulfate fertilizer were used after 40 and 80 days of planting: 0 mL/L (Z0), 30 mL/L (Z1), and 60 mL/L (Z2). The experimental design of this study was a Randomized Complete Block Design (RCBD) with three replicates/treatments. Soil and plant samples were collected at the end of the experiment. The results showed the superiority of the treatments H3Z2 and H3Z1, suggesting the dependence on the availability of zinc and phosphorus in the soil that impacted its content in the plant, dry matter, and grain weight. The H3Z2 and H3Z1 treatments achieved 0.683 and 0.678 mg Zn/kg soil and 0.241 and 0.230 kg Zn/ha and 26.25, 24.02 mg P/kg soil and 22.49 and 21.51 kg P/ha and 10.19 and 9.75 mg Mg/kg soil, and 7.712 and 7.632 kg Mg/ha, respectively. [ABSTRACT FROM AUTHOR]

In order to investigate the effects of different application methods of zinc fertilizer on the zinc content of wheat (Triticum aestivum L.) grains in China, published literature was reviewed and relevant data was collected for analysis. The results show that the main application methods for zinc fertilizer in China were soil, foliar, and soil+foliar application, and the average zinc input of soil application (12.6 kg·hm-2 ) was higher than that of foliar application (1.57 kg·hm-2 ) . The distribution of zinc content in wheat grains without zinc fertilizer ranged from 14.6 mg·kg-1 to 50.0 mg·kg-1, and 95.3% of wheat grains had zinc content <40 mg·kg-1 . The distribution of zinc content in grains after soil+foliar application ranged from 24.0 mg·kg-1 to 70.9 mg·kg-1, and 76.2% of wheat grains had zinc content >40 mg·kg-1 . The average increase rate of zinc content in grains under different application approaches was as follows：soil+foliar application (62.6%) > foliar application (47.2%) > soil application (24.6%) . There was a significant positive correlation between the increase rate of wheat grain zinc content and the amount of exogenous zinc input in soil and foliar application, i.e., when the zinc input increased by 1 kg per hectare, the zinc content in grains increased by 0.74% and 16.39%, respectively. The average utilization efficiency of zinc fertilizer after foliar application (7.27%) was higher than that of soil application (0.59%) and soil+foliar application (0.94%) . Therefore, the zinc content of wheat grains could be increased using different application methods; soil + foliar application was most effective, while foliar application possessed the highest zinc utilization efficiency. [ABSTRACT FROM AUTHOR]

Introduction Among various non-biological stresses, drought stress is the most important factor that has limited production in the agricultural sector of the country (Akhzari and Pessarakli, 2016). Today, the supply of oilseeds for the extraction of vegetable oils needed for various industrial, edible, medicinal and cosmetic uses is one of the basic needs of the current population growth (Beynam, 2015). Balangu (Lallemantia iberica L.) is an annual, herbaceous and drought-resistant plant belonging to the mint family (Lamiaceae). With medicinal-oil properties, it is considered a multi-purpose plant in agriculture (Hendawy et al., 2015). In order to check and predict the phenological stages of the planted plants in an area, the relationship between the phenological stages and the thermal factor should be considered. For this purpose, thermal units of growth degree days (GDD) are used to check the amount of heat needed to pass each growth stage of plants (Kumari et al., 2020). In plants under drought stress, where the absorption of nutrients through the root faces a problem due to the decrease in soil water volume, the absorption of micronutrients such as iron and zinc can be effective through foliar spraying. (Rafique et al., 2015). In the conditions of lack of water resources, like what is happening in our country, it is necessary to change the agricultural pattern towards planting plants adapted to dry land, as well as ways to increase yield per unit area. Therefore, the purpose of this research was to investigate the development of Balangu planting and the role of foliar application of iron and zinc micronutrients on phenology and the adjustment of stress effects. Materials and Methods This research was conducted in the research farm of Razi University of Agriculture and Natural Resources, Kermanshah during two consecutive years (2017-2018 and 2018-2019) as a split-plot-factorial experiment in the form of a basic randomized complete block design with three replications. The experimental treatments include: irrigation (Water deficit after flowering and Normal) in the main plots, foliar spray factors (zero, four and eight per thousand concentrations of iron and zinc sulfate) and foliar application time (at the beginning of the vegetative and reproductive growth stage) were factorially placed in sub-plots. The seeds (native population of Songhor region of Kermanshah province) were planted manually at a depth of two centimeters and with a density of 400 plants per square meter in a row at the first appropriate time in late March of 2017 and 2018. Application of nitrogen, phosphorus and potash fertilizers was based on need. Dehydration stress was applied by stopping irrigation from the time of full flowering (opening of 50% of flowers). Results and Discussion The results showed that, with the application of water stress, the seed yield and oil yield decreased by 24% and 17%, respectively, and the oil percentage increased by 8% compared to the treatment without water stress. Also, water deficit stress reduced the number of days and heat requirement to maturity by 10 days and 275 growth days degree, respectively. The greatest increase in oil yield compared to the treatment without foliar spraying (control) was related to the 4 and 8 per thousand zinc foliar treatments in reproductive stage and under stress conditions, which increased these traits from 339 and 283 respectively in conditions Lack of stress and water deficit stress increased to 539 and 513 kg/ha. The greatest effect of iron and zinc foliar application treatments on increasing plant height and the number of days and heat requirement to maturity stage was related to 4 and 8 per thousand iron and zinc foliar application in the vegetative growth stage. Conclusion In the present study, it can be concluded that the Balangu having adaptability, suitable production, relatively short growth period and matching the length of the growth period with the rainfall of the study area, and it can be considered as a common plant for rotation in this region. Foliar application of iron and zinc micronutrient elements should be used by farmers to moderate the effects of water deficit stress, taking into account its small and economical amounts. [ABSTRACT FROM AUTHOR]

Due to climate changes, we encounter irregular and low rainfall. It is important to effectively use groundwater and to select crops that can be grown with deficit irrigation in the summer period. Restricted irrigation reduces water consumption but it may cause losses in terms of yield and quality. Different agronomic practices can be used to minimize these losses. One of these practices is the application of foliar zinc fertilizer. In previous studies, zinc application was found to increase the bioavailability of cowpea grain. In this study, the effects of the application of zinc fertilizer on yield, some yield components, physiological traits, and grain quality characteristics of three different cowpea genotypes (Akkız, Karagöz, and a Local variety) were investigated under full (100%) and deficit (50%) irrigation. The field experiment was conducted using a randomized complete block split–split plot design with irrigation rates (100% and 50%) and foliar zinc application (0 and 60 kg ha−1) with three replicates used each season (2020 and 2021 growing seasons of cowpea) in the field crops trial fields of the Aydin Adnan Menderes University, at the Faculty of Agriculture, located in the western region of Turkey. Yield and quality characteristics such as grain yield, some yield components, grain protein content, grain mineral matter content, and grain amino acid content were measured. According to the data obtained, a 40% yield reduction was observed under restricted irrigation in the first year of the study. It was determined that zinc application under restricted irrigation increased the yield by approximately 10%. The second-year results found that the amount of essential amino acids such as histidine, phenylalanine, valine, and lysine increased with the zinc application. This study highlights that deficit irrigation conditions caused stress in the plant and caused losses in the yield and quality. Still, the severity of this stress was reduced by foliar zinc application, and it was determined that it positively affected grain yield and bioavailability in cowpea. [ABSTRACT FROM AUTHOR]

Copyright of Journal of Plant Production is the property of Egyptian National Agricultural Library (ENAL) and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The excessive fertilizer application is a recurring problem in agriculture as it not only harms the soil texture but also diminishes the micronutrient availability i.e., zinc (Zn). Zn is an essential element for crop production and quality, and is also indispensable for human diet. Zn deficiency is a common problem in alkaline soils. This study aims to assess the efficiency of three different Zn fertilizers in Phaseolus vulgaris plants, grown in an alkaline soil. P. vulgaris plants were grown in an experimental greenhouse under four different treatments: control (no Zn fertilization), ZnSO4, the chelate diethylenetriaminepentaacetic acid (DTPA-Zn), and Zn nanoparticles (NfsZnO). Each Zn source was applied at three different doses (0, 25, 50, 100 mg kg−1). Parameters related to biomass, photosynthetic pigments, and Zn accumulation were analyzed. Zn sources enhanced bean pod growth and yield. Furthermore, the three Zn sources increased Zn accumulation in all plant organs, except in leaves. Whereas, plants supplied with 100 mg kg−1 of DTPA-Zn and 25 mg kg−1 of NfsZnO accumulated the highest bean Zn concentration. Generally, plants supplied with DTPA-Zn and NfsZnO showed the highest Zn content values. Besides, Zn sources enhanced the values of Zn efficiency parameters in a dose-dependent manner. According to the results, the three Zn fertilizers were effective to increase the parameters analyzed in P. vulgaris. However, DTPA-Zn and NfsZnO were more effective to enhance yield and bean Zn content, and thus can be useful for bean cultivation in alkaline soils. [ABSTRACT FROM AUTHOR]

Using nanofertilizers in certain concentrations can be a novel method to alleviate drought stress effects in plants as a global climate problem. We aimed to determine the impacts of zinc nanoparticles (ZnO-N) and zinc sulfate (ZnSO4) fertilizers on the improvement of drought tolerance in Dracocephalum kotschyi as a medicinal-ornamental plant. Plants were treated with three doses of ZnO-N and ZnSO4 (0, 10, and 20 mg/l) under two levels of drought stress [50% and 100% field capacity (FC)]. Relative water content (RWC), electrolyte conductivity (EC), chlorophyll, sugar, proline, protein, superoxide dismutase (SOD), polyphenol oxidase (PPO) and, guaiacol peroxidase (GPO) were measured. Moreover, the concentration of some elements interacting with Zn was reported using the SEM-EDX method. Results indicated that foliar fertilization of D. kotschyi under drought stress with ZnO-N decreased EC, while ZnSO4 application was less effective. Moreover, sugar and proline content as well as activity of SOD and GPO (and to some extent PPO) in treated plants by 50% FC, increased under the influence of ZnO-N. ZnSO4 application could increase chlorophyll and protein content and PPO activity in this plant under drought stress. Based on the results, ZnO-N and then ZnSO4 improved the drought tolerance of D. kotschyi through their positive effects on physiological and biochemical attributes changing the concentration of Zn, P, Cu, and Fe. Accordingly, due to the increased sugar and proline content and also antioxidant enzyme activity (SOD, GPO, and to some extent PPO) on enhancing drought tolerance in this plant, ZnO-N fertilization is advisable. [ABSTRACT FROM AUTHOR]

Recently, nanotechnology has offered the practice of a new generation of foliar fertilizers containing nanoparticles. One of the most promising zinc-containing foliar fertilizers is zinc hydroxy nitrate. Along with this, important aspects of its application in practice, such as the number and timing of sprays and the agronomic response of different maize hybrids, remain understudied. The objective of this study was to investigate the agronomic responses of maize hybrids to foliar fertilization by zinc in the form of zinc hydroxy nitrate suspension. Grain yield and its components were used as evaluation criteria. A total of ten hybrids from three maturity groups (FAO 400, 500 and 600/700) were tested. Considerable differences were found between the groups for the grain yield parameters. Furthermore, a significant effect of Zn application was observed for grain yield, which increases up to 12.2% for P0216 FAO 480. The best effect is obtained by double spraying at 4-5 fully emerged leaf and 8-9 fully developed leaf. The most sensitive to foliar zinc fertilization are the hybrids from the early maturity group FAO 400. No direct correlation was found between foliar zinc fertilization and protein, fat and starch content in the maize grains. The preparation of the zinc hydroxide nitrate with composition Zn5 (OH)8(NO3)2·2H2O was performed by pouring a NaOH solution into Zn (NO3)2·6H2O under vigorous stirring. All samples were characterised in detail by thermal analysis, X-ray diffraction, scanning electron microscopy, and inductively coupled plasma (ICP) mass spectrometry to determine their physicochemical properties, morphology and content. The field experiment was conducted in four variants, three repetitions for each hybrid. It was concluded that the synthesised zinc hydroxy nitrate has potential as a successful long-term foliar fertilizer. [ABSTRACT FROM AUTHOR]

The trace element zinc plays a vital role in the growth and development of corn. In this study, a greenhouse was used to simulate the field environment, and five zinc fertilizer application gradients(10, 20, 30, 40, 50 kg/ha) were set to analyze the effects of external application of zinc fertilizer on the main agronomic, economic and quality traits of fruit-type sweet corn Xuetian 7401. The results showe that zinc application could effectively increase plant height, ear height, and regularity of Xuetian 7401. Plant height and ear height reached the maximum at the zinc application levels of 40 kg/ha and 50 kg/ha, respectively, which increased by 17 cm and 11 cm compared with those of the control. The silking stage and anthesis stage of Zinc 50 kg/ha treatment were shortened by 1.7 days and 3.2 days compared with those of the control, respectively, both of which reached a significant level. Zinc treatment could generally prolong the anthesis-silking-interval(ASI), but the difference was not significant. Zinc application could keep the leaves green, increase the chlorophyll content by 27.4%, increase the photosynthetic efficiency of the ear leaves. For yield, zinc application had no significant effect on the increase of ear length, but could significantly reduce the tip length, and increase the yield per plant by 14.4% under the level of zinc application of 40 kg/ha. For quality, zinc application could effectively improve the sugar and zinc content in grains and the content was in direct proportion to external, application of zinc fertilizer, but it could affect the absorption of iron. However, under the treatment of high amount of zinc application, the accumulation of zinc in grains was easy to exceed the national standard of crop grains in China, resulting in heavy metal zinc poisoning. The optimal amount of zinc was the medium treatment of zinc application(30 kg/ha), it could effectively improve the main agronomic, economic and quality traits of fruit-type sweet corn Xuetian 7401, and enhance its commodity value. [ABSTRACT FROM AUTHOR]

The present study is carried out to establish the biofortification of zinc in potato (Solanum tuberosum L.) and tomato (Solanum lycopersicum L.) plants through the application of zinc oxide nanoparticles (ZnONPs). The mycogenic ZnONPs are synthesized by using Aspergillus flavus biomass and characterized to ascertain the size, shape, and concentration of synthesized nanoparticles. The ZnONPs are applied by foliar spray to the field‐grown potato and tomato crops and the biofortification level is recorded by Atomic Absorption Spectroscopy (AAS). A nanotoxicity assessment is done by comparing the amount of cell death and accumulation of reactive oxygen species (ROS) in control and ZnONPs treated plants. The AAS analysis reveals significant accumulation of the zinc in leaves of potato plants but insignificant accumulation is observed in the tubers. However, a significant accumulation of zinc is observed in the leaves and fruits of the tomato plants (p ≤ 0.05). The nanotoxicity evaluation studies show comparable and statistically insignificant toxicity in control plants as compared to plants treated with ZnONPs. The study concludes that biofortification through the means of ZnONPs is a cost‐effective and eco‐friendly approach that can be used as an alternative to the hazardous chemical zinc fertilizers. [ABSTRACT FROM AUTHOR]

Appropriate foliar application of zinc (Zn) and zinc oxide nanoparticles (ZnO-NPs) is important for the proper growth and yield of tomato. However, the effects of foliar application of Zn and ZnO-NPs were not well-studied on tomato production. A pot experiment was conducted at glasshouse (8D) conditions under the Faculty of Agriculture, Universiti Putra Malaysia (UPM) to evaluate the effectiveness of Zn and ZnO-NPs on growth, yield, nutrient uptake, and fruit quality of tomatoes and to compare between the Zn nutrient and ZnO-NPs. Treatment combinations were 14 viz. T1 = 0 (control), T2 = 1500 ppm (mg/L) Zn nutrient, T3 = 2000 ppm (mg/L) Zn nutrient, T4 = 2500 ppm (mg/L) Zn nutrient, T5 = 75 ppm ZnO nanoparticle, T6 = 100 ppm ZnO nanoparticle, and T7 = 125 ppm ZnO nanoparticle along with two tomato varieties. The experimental design was a split plot with four replications. Results indicated that foliar application of 100 ppm ZnO-NPs performed best in terms of growth parameters, physiological traits, yield attributes, yield, and quality traits of tomatoes. The same treatment (100 ppm ZnO-NPs) contributed to attain the highest nutrient uptake. Recovery use efficiency of Zn was highest with foliar application of 75 ppm ZnO-NPs. The highest yield increment (200%) over control was from foliar sprayed with 100 ppm ZnO-NPs. Comparing the two varieties, MARDI Tomato-3 (MT3) showed better than MARDI Tomato-1 (MT1). As is appears from the results, foliar application of zinc oxide nanoparticles was more efficient than conventional zinc fertilizer. Therefore, the foliar sprayed with 100 ppm ZnO-NPs can be suggested to improve quantity and quality of tomato in glasshouse soil conditions. [ABSTRACT FROM AUTHOR]

Copyright of Journal of Henan Agricultural Sciences is the property of Editorial Board of Journal of Henan Agricultural Sciences and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Journal of Henan Agricultural Sciences is the property of Editorial Board of Journal of Henan Agricultural Sciences and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)