Form Of ZnSO4 Research Articles

Copper, Zinc, and Lead Recovery from Jarosite Pb–Ag Tailings Waste (Part 2)

The present paper describes the technological solution for obtaining Cu, Zn, Pb, and Ag from jarosite waste raw material, with its simultaneous separation from In and Fe. By roasting at low temperatures, iron was transformed from the Fe2(SO4)3 form into Fe2O3, which is insoluble in water and slightly soluble in acid. Copper sulfate and zinc sulfate are present in jarosite as sulfates. During temperature roasting, the copper and zinc were still in the form of CuSO4 and ZnSO4, i.e., they were easily dissolved in water. This procedure led to good selectivity of Cu and Zn compared to Fe. After water leaching, PbSO4 and Ag2SO4 remained in the solid residue. By treating jarosite with a content of 0.7% Cu, 5.39% Zn, and 5.68% Pb, products of commercial quality were obtained. By roasting jarosite in an electric furnace and leaching the roasted sample in water, leaching degrees of 91.07%, 91.97%, and 9.60% were obtained for Cu, Zn, and Fe, respectively. Using 1 M NaOH in the leaching solution, 99.93% Fe was precipitated to pH = 4. Cu in the form of CuSO4 was further treated by cementation with Zn, after which cement copper was obtained as a commercial product. Zn in the form of ZnSO4 was further treated by precipitation with Na2CO3 to obtain ZnCO3 concentrate of commercial grade. The total recovery of Pb and Ag, which were treated by chloride leaching, was 96.05% and 87.5%, respectively. The resulting NaPbCl3 solution was further treated with Na2CO3 solution, whereby PbCO3 was obtained as a commercial product. The produced PbCO3 could be further subjected to roasting to obtain soluble PbO. In these investigations, PbCO3 was smelted where a Pb anode was obtained; this was electrolytically refined to a Pb cathode. The proposed process does not pollute the environment with As and Cd.

Sustainable management practices for durum wheat production: Analyzing specific agronomic interventions on productivity, grain micronutrient content, and quality

As compared with single agronomic crop management practices during grain formation, knowledge about integrated agronomic management practices on grain mineral composition and grain technological properties in durum wheat is limited. This knowledge is important for determining management strategies aimed at increasing grain yield without affecting grain nutritional quality. Integrated agronomic practices such as foliar nutrient application × seeding rate × varieties combined with growing locations were investigated to evaluate the dynamics of yield and grain quality traits. Two durum wheat varieties, three-level of micronutrients (i.e. control, FeSO4, and ZnSO4), and four levels of seeding rate (i.e. 100, 125, 150, and 175 kg ha−1) were arranged in split-split plot design under two different growing locations (environments). The main plots were assigned to the varieties, subplots to micronutrients, and sub-sub plots to the seeding rate treatments. Zinc and iron were applied in a form of ZnSO4 and FeSO4 at the early flowering stage, both at a rate of 25 kg ha−1. Results showed a linear increment in biomass (21.5%) and grain yield (23.5%) under a high seeding rate, even though the 1000-grain weight, the number of grains spike−1, spike length, and the number of grains spike−1 were decreased. Higher varietal and environmental response of seeding rate was observed between varieties. The grain protein content, gluten, and zeleyn index decreased as the seeding rate increased. Grain micronutrient content was significantly influenced by seeding rate and varietal difference. The grain protein content was higher in a dryland environment than in a wet environment. A combined use of density-tolerant varieties, high seeding rate, and foliar-based iron application can improve the grain yield from 2.01 to 3.20 t ha−1 under a potential environment. Hence, all stakeholders should consider the genotype (G), environment (E), management (M), and their synergies, as far as grain yield and quality are considered simultaneously.

Evaluation of Zinc efficiency and some of nutritional and physiological responses of tomatoes cultivars

Zinc (Zn) is an enzyme cofactor involved in plant metabolism, required in auxin biosynthesis and membrane integrity required to maintain ion transport systems. Nonetheless, only a few studies have shown that Zn is efficient in tomatoes. Thus, the present study aimed to analyze the responses of several tomato cultivars to Zn application and classify the tomato cultivars that were efficient and responsive to Zn. This study utilized seven commercial lowland tomato cultivars (Tyrana, Permata, Mirah, Tombatu, Zamrud, Tymoti, and Ratna) and comprised five levels of Zn dose 0, 10, 20, 30, and 40 mg Zn kg−1, which is given in the form of ZnSO4 7 H2O. Based on the results of the analysis, the study revealed that the application of ZnSO4 up to 40 mg Zn kg−1 could increase the growth of tomato roots, while at a dose of 20 mg, Zn kg−1 could provide the most excellent physiological efficiency and utilization efficiency in tomato plants. The Tyrana and Permata cultivars are a group of cultivars that are efficient and responsive to Zn. This shows that both cultivars can grow under conditions of low Zn supply and response to Zn fertilizer.

Effect of Vermicompost and Zn on Physico-Chemical Properties of Soil in Cultivation of Okra (Abelmoschus esculentus L.) var. Supper Green

The objective of the experiment was to evaluate the effect of vermicompost and zinc as form of ZnSO4.7H20 on soil health and yield attributes of okra. The design applied was 3x3 randomized block design having three levels of vermicompost @ 0, 50 and 100% ha-1, three levels of Zn @ 0, 50 and 100% ha-1 respectively. It was observed that treatment T9 (Vermicompost @ 100% + Zn @ 100%) improved the soil WHC, OC, available N, P, and K, resulted in a slight chenge in soil pH 7.28, EC 0.388 dS m-1 and bulk density 1.40 Mg m-3 and particle density 2.64 Mg m-3. In post- harvest soil of fertilizers observations were resulted in significant increase in pore space 48.20%, water holding capacity 43.22 %, organic carbon 0.52 %, and available N 307.14kg ha-1, P 34.14 kg ha-1, K 186.58 kg ha-1 and Zn 0.57 mg kg-1, significant increase in case of Nitrogen kg ha-1, Phosphorus kg ha-1, Potassium kg ha-1 and Zinc mg kg-1 was found to be significant among other treatments in okra cultivation and soilquality improvement. The maximum yield regarding, gave the best results with respect to plant height 120.70 cm, number of leaves plant-1 49.31, number of fruit plant-1 24.22, and yield of fruits 135.59 q ha-1. It gave highest yield 135.59 q ha-1. It was also revealed that the application of Zinc with organic manures was excellent source for fertilizer.

Efficacy of Nitrogen and Zinc Application at Different Growth Stages on Yield, Grain Zinc, and Nitrogen Concentration in Rice

Zinc (Zn) is an essential element involved in human metabolism, which can be supplied by an appropriate diet. Enhancing Zn enrichment in rice grains through agronomic biofortification is advocated as an immediate and effective approach to combat micronutrient malnutrition in hu-man. It has been well-documented that high grain Zn accumulation in rice can be achieved by Zn fertilizers management. This study evaluated the effects of foliar nitrogen (N) and Zn applied at the flowering and milky stages of brown rice plants with and without soil Zn application. A glasshouse pot experiment was conducted using a completely randomized design with four replicates. Soil Zn in the form of ZnSO4 was applied at 0 and 50 kg ha−1. Foliar fertilizer of 1% urea along with 0.5% ZnSO4 was applied and assigned as (1) nil foliar N and Zn (N0Zn0), (2) foliar N with nil Zn (N+Zn0), (3) nil foliar N with foliar Zn (N0Zn+), and (4) foliar N and Zn (N+Zn+) at flowering and milky stages. Foliar application of N and Zn increased grain yield and yield components in both soil Zn conditions. Grain Zn concentration in brown rice was the highest when foliar N and Zn were applied under nil soil Zn conditions; however, grain N concentration decreased by 13.1–28.5% with foliar application at flowering and 18.8–28.5% with application at the milky stage. The grain Zn content was increased by foliar application of N0Zn+ and N+Zn+ at flowering and milky stages. Applying foliar N and Zn at flowering or milky stages tended to increase the grain N content when Zn was applied to the soil, while nil soil Zn decreased the N content by 26.8% at flowering and milky stages under N0Zn+. The results suggest that the milky stage is the most suitable for foliar application of Zn for increasing (i) grain yield and (ii) N and Zn concentrations in brown rice without having a dilution effect.

Evaluation of appropriate method for Zn fertilization of rice in the lower gangetic plain of West Bengal, India

Considering the essentiality of zinc as well as its widespread deficiencies in rice soils, a field experiment was conducted in2019 at Central Research Farm of Bidhan Chandra Krishi Viswavidyalaya, Gayeshpur, Nadia district in the lower Gangetic plain of West Bengal to study the effect of different sources of Zn as well as the methodology of its application involving different combinations of soil application and spraying at different stages of crop growth on the enhancement of the Zn-content in rice crop. The application of Zn produced significantly better results than control with respect to grain yield as well as zinc content in grain. The treatment comprising application of Zn @10 kg ha-1 in the form of ZnSO4.7H2O in soil along with one foliar spray in the form of Zn-EDTA @0.5% at the maximum tillering stageproved superior statistically recording highest grain yield. Results also revealed thatsoil application of zinc at the time of plantingin combination of one foliar spray @ 0.5% at maximum tillering stage was found more effective than application of zinc only through two foliar applications.

Sequential Extraction Resulted in Similar Fractionation of Ionic Zn, Nano- and Microparticles of ZnO in Acidic and Alkaline Soil

The evaluation of nanoparticle bioavailability or the bioavailability of dissolved elements by direct measurement through plant uptake is a strenuous process. Several multi-step sequential extraction procedures, including the BCR sequential extraction procedure, have been created to provide potential accessibility of elements, where real soil-plant transfer can be problematic to implement. However, these have limitations of their own based on the used extractants. For the purposes of our research, we enriched two soils: an untilted forest soil with naturally acidic pH and a tilted agricultural soil with alkaline pH by three Zn forms—ionic Zn in the form of ZnSO4, ZnO nanoparticles (ZnO NP) and larger particles of ZnO (ZnO B)—by batch sorption. We then extracted the retained Zn in the soils by BCR sequential extraction procedure to extract three fractions: ion exchangeable, reducible, and oxidizable. The results were compared among the soils and a comparison between the different forms was made. Regardless of the difference in soil pH and other soil properties, ZnO NP, ZnO B, and ionic Zn showed little to no difference in the relative distribution between the observed soil fractions in both forest soil and agricultural soil. Since ionic Zn is more available for plant uptake, BCR sequential extraction procedure may overestimate the easily available Zn when amendment with ionic Zn is compared to particulate Zn. The absence of a first extraction step with mild extractant, such as deionized water, oversimplifies the processes the particulate Zn undergoes in soils.

Effect of dietary supplementation of different levels of zinc on feed intake, growth performance, carcass characteristics and physical quality of meat in sheep

An experiment was conducted in Deccani ram lambs to study the effect of supplementing different levels of zinc (Zn) in the diet on growth performance, feed intake, carcass characteristics and meat quality. Twenty-four weaned native Deccani ram lambs weighing around 12-15 kg were divided into four groups of six each. They were fed with adlib finely chopped maize straw and concentrate feed @ 1% of body weight for 120 days. Concentrate feed offered to different groups differed in the zinc content which was supplemented in the form of ZnSO4.7H2O. Group 1 was used as negative control where no mineral mixture was added in the concentrate mixture. In Group 2 (control), mineral mixture was used @ 2%. In group 3 and 4, in addition to mineral mixture, ZnSO4.7H2O was added @ 70g and 140g per 100 kg concentrate mixture respectively. Feed intake and body weights of animals were recorded during the entire experimental period. After the feeding trial, animals were slaughtered to study the carcass characteristics and meat quality parameters. The results indicated that additional zinc supplementation did not show any effect (P>0.05) on feed intake or body weight gain between groups. Carcass characteristics were also similar (P>0.05) between the groups There was significant (P<0.01) decrease in shear force value with increased Zn level in the diet indicating that tenderness of meat was influenced by Zn supplementation in sheep diets.

Effects of foliar applied zinc in the form of ZnSO4 and Zn-amino acid complexes on pistachio nut yield and quality

Despite the importance of Zn nutrition, little information is available on the effectiveness of foliar Zn application, in general, and Zn-amino acid complexes in particular on pistachio nut yield and quality. Response of pistachio (Pistachio vera L. cv. Akbari) to foliar application of zinc (Zn) in the form of mineral (ZnSO4) and complexed with methionine (ZnMet), lysine (ZnLys), and lysine plus methionine (ZnLysMet) was investigated. Lysine alone treatment was used to distinguish the effects of accompanying Lys. A control treatment with no amino acids and Zn was also used. The critical deficiency concentration of Zn in the leaf to achieve the highest 100-kernel mass was 37.6 mg kg−1. Foliar application of Zn significantly increased leaf Zn concentration in comparison with control. In both years, foliar supply of Zn in the form of complexed with amino acids resulted in a significant increase of total nut yield, fresh mass of 100-nut, and spilled nuts. A significant decrease in the empty nuts was also observed by Zn application. The effectiveness of ZnMet in improving yield and quality attributes of pistachio was in general, higher than the other Zn sources.

Studies on foliar application of zinc as bio-fortification strategy to enhance grain zinc content in rice (Oryza sativa L.) genotypes

Zinc (Zn) deficiency is a concern for nearly half of the world population. Biofortification through foliar Zn application is an approach to reduce human Zn deficiency. Knowledge available on effect of foliar applied zinc towards biofortification efficiency and bioavailability of rice grain is limited. Pot experiment with rice was conducted to study the effect of foliar applied zinc along with soil application of recommended dose of N: P: K: Zn for rice. Two contrasting groups of four cultivars each with respect to seed zinc based on previous screening were selected (high seed zinc types and low seed zinc types). Zinc was applied in the form of ZnSO4.7H2O foliar application at vegetative stage and at reproductive stage in three different doses (recommended dose, 10% lower than recommended dosage and 10% higher than recommended dosage). Results suggest that foliar zinc application is effective in enhancing grain zinc when applied with recommended dose of soil zinc fertilizer irrespective of inherent zinc acquisition capacity by roots. Stem had higher Zn accumulation at 65 DAS indicating translocation of foliar applied zinc. At 50% panicle initiation stage, there was higher zinc in leaf compared to stem and developing grain implying Zn movement from stem to seed. Zn analyzed at different stages of grain filling till harvest showed an increase in Zn content both in high and low zinc types. Higher seed Zn was observed in long duration varieties. Using long duration varieties for foliar biofortification could be an effective strategy to overcome Zn deficiency.

Biochemical, molecular, and elemental profiling of Withania somnifera L. with response to zinc stress.

Zn stress seriously induces various toxic responses in Withania somnifera L., when accumulated above the threshold level which was confirmed by investigating the responses of protein, expression of antioxidant enzymes, and elemental profiling on accumulation of Zn. Zn was supplemented in the form of ZnSO4 (0, 25, 50, 100, and 200 μM) through MS liquid medium and allowed to grow the in vitro germinated plants for 7 and 14 days. The study revealed that when the application of Zn increased, a significant reduction of growth characteristics was noticed with alterations of proteins (both disappearance and de novo synthesis). The activity of CAT, SOD, and GPX were increased up to certain concentrations and then declined, which confirmed through in-gel activity under different treatments. RT-PCR was conducted by taking three sets of genes from CAT (RsCat, Catalase1, Cat1) and SOD (SodCp, TaSOD1.2, MnSOD) and found that gene RsCat from CAT and MnSOD from SOD have shown maximum expression of desired genes under Zn stress, which indicate plant's stress tolerance mechanisms. The proton-induced X-ray emission study confirmed an increasing order of uptake of Zn in plants by suppressing and expressing other elemental constituents which cause metal homeostasis. This study provides insights into molecular mechanisms associated with Zn causing toxicity to plants; however, cellular and subcellular studies are essential to explore molecule-molecule interaction during Zn stress in plants.

Bioaccumulative activity of Ludwigia peploides on heavy metals-contaminated water

Abstract Heavy metal pollution of soil and water has become a serious environmental problem in recent decades. This study was carried out to investigate the Ludwigia peploides bioremediation activity against heavy metals-contaminated water. The plant Ludwigia peploides was collected from Asa River, in Ilorin Kwara State, alongside with the water sample. The pond water collected was distributed into six (6) different 5-litre buckets (Grouped A–F) in which the plant was cultivated for experimentation within a period of 28 days in the laboratory. Group A served as the control which contained only the natural environment of the plant, Groups B, C and C contained added 5.0 mg/litre Cu, Pb and Cr respectively in the form of CuSO4, PbNO3 and K2Cr2O7 respectively. Group E contained 0.5 mg/litre added Cd in the form of CdNO3 while Group F contained 500 mg/litre added Zn in the form of ZnSO4. The Percentage removal efficiency, Translocation factor, Bioconcentration factor and Bioaccumulation coefficient of the plant leaves and roots were evaluated. Also, activities of superoxide dismutase (SOD) and catalase; MDA, chlorophyll and proximate composition of the leaves were evaluated. There was significant increase ( p 0 . 05 ) in the chlorophyll-a content of all the test samples when compared with the control. There was also significant increase in the MDA concentration in the plant leaves and in the catalase specific activity of the plant cultivated with chromium, lead and cadmium. There was significant reduction ( p 0 . 05 ) in SOD activity of the plant cultivated with chromium and zinc at the early stage of cultivation. The translocation factor (TF) of the plant ranges between 0.10–2.11 while the bioaccumulative coefficient (BAC) ranges between 0.10 and 2.68. We therefore conclude that the roots of Ludwigia peploides have ability to remove copper from contaminated water effectively, and to a moderate extent chromium, lead and cadmium. Also, the leaves of the plant absorb high percentage of chromium from the contaminated environment. This study evidenced that Ludwigia peploides may serve as an effective bioremediation agent for correcting contaminated water.

Induction of Metallothionein in Rat Liver by Zinc Exposure: A Dose and Time Dependent Study.

Metallothioneins (MTs) are low molecular weight ubiquitous metalloproteins with high cysteine (thiol) content. The intracellular concentration of zinc (Zn) is tightly regulated and MT plays a crucial role in it. The present study investigates the relationship between the Zn status (as a function of Zn concentration and time) in the rat liver and the occurrence of hepatic MT. For dose dependent study, four experimental groups, one control and three receiving different levels of metal supplementation, were chosen [Group 1 control and Group 2, Group 3, Group 4 receiving subcutaneous dose of 10, 50 and 100mg of Zn/kg body weight (in the form of ZnSO4·7H2O), respectively]. For the time dependent expression of MT, again four experimental groups, i.e. Group 5 control and Group 6, Group 7, Group 8 receiving 50mg of Zn/kg body weight (in the form of ZnSO4·7H2O) subcutaneously and sacrificed at different time intervals after last injection i.e. 6, 18, 48h, respectively were chosen. Isolation of MT was done by using combination of gel filtration and ion exchange chromatography while characterization of MT fraction was carried in the wavelength range 200-400nm. Expression of MT was studied by using Western blot analysis. The results revealed that the MT expression increases with increasing the dose of Zn administered and maximum at 18h after last Zn injection. Accumulation of MT with increase dose would help in maintaining the intracellular Zn concentration by its sequestration which further reduces the possibility of undesirable binding of Zn to other proteins significantly and maintains Zn homeostasis. The maximum expression of MT at 18h is indicative of its half life.

Effect of Zn toxicity on the level of lipid peroxidation and oxidative enzymes activity in Badami cultivar of pistachio (Pistacia vera L.) colonized by ectomycorrhizal fungus

Zn is one of the eight trace elements essential for the normal growth and reproduction of crop plants. Plants possess cellular mechanisms to detoxify heavy. On metal-contaminated soils, ectomycorrhizal (ECM) fungi may improve plant growth through an enhanced nutrition or by alleviation toxicity of the metals. Agaricus bisporus,an edible mushroom has been observed to grow under Pistacia vera plantations in orchards of Kerman, Iran and it forms ectomycorrhiza with the tree. In this study a glasshouse experiment was conducted to investigate the effects of ectomycorrhizal pistachio trees colonized with fungus A. bisporus on Zn toxicity. Half of the plants were inoculated with the fungus. Zn was supplied in the form of ZnSO4 at 0, 30, 60, 90 and 120 μM. Half of the Non-mycorrhizal plants were used as controls and treated with same concentrations of Zn. The results showed that the, increase of Zn concentration caused an increase in the malondialdehyde (MDA) content in the shoots of the whole plants. The ECM plants showed a lower MDA content than the non-ECM plants. Zn caused an induction in Superoxide dismutases, catalase (CAT) and ascorbate peroxidase activity in the leaves of the mycorrhizal (M) and non mycorrhizal plants (NM), but it was dramatically more in mycorrhizal plants. A decrease of ascorbate content was induced by increasing the Zn concentration where it was higher in mycorrhizal plants but all metal treatments increased dehydroascorbate contents in both M and NM plants. Measurements of Zn concentrations indicated that Zn mainly accumulated in the roots of the ECM plants.

The Effect of Zinc Nutrition on Two Olive (Olea europaea L.) Cultivars Components and Alleviate Oxidative Damage in Salinity Conditions

The role of zinc (Zn) in enhancing defense capacity of several plants against salinity has been demonstrated but there is limited information on the impact of Zn nutrition on alleviating salinity-induced oxidative damage in olive. One-year-old seedlings of two varieties of olive (Olea europaea L. cvs. Frontoio and Conservolea) supplied with three Zn levels (0, 1 and 5 mM in the form of ZnSO4.7H2O) were exposed to four salinity levels (0, 40, 80 and 120 mM NaCl). The increase in plasma membrane permeability and elevated leakage of potassium (K) and Zn from the olive roots were considered as indices of oxidative damage caused by salinity on root cells. In contrast, root membrane permeability and leakage of Zn and K ions in plants supplied with Zn was less than those non-supplied with Zn. Addition of Zn resulted in higher activity of CAT and APX. Higher salt-tolerance of Frontoio cultivar was associated with higher concentration of sulfhydryl (-SH) groups and lower membrane permeability of its roots in comparison with Conservolea cultivar. Based on the results obtained, addition of Zn improved plant enzymatic defense system and partly alleviated oxidative injuries induced by salinity on the olive.

Effect of phosphorus and zinc nutrition on growth and yield of fodder cowpea

An experiment consisting of four phosphorus levels (0, 40, 60 and 80 kg/ha P2O5) and five zinc levels (0, 10, 20, 30 and 40 kg/ha ZnSO4) was laid out in randomized block design in factorial mode to find out the effect on yield and quality of fodder cowpea [Vigna Unguiculata (L.)Walp.]. Growth parameters viz. plant height, number of leaves, number of branches, leaf length, leaf width and leaf stem ratio were improved with the application of 60 kg/ha P2O5 and 20 kg/ha ZnSO4. Application of 60 kg/ha phosphorus recorded 27.64 t/ha yield, which was 7.50 and 55.6 % higher than 40 kg/ha and no phosphorus application, respectively. Application of zinc in the form of ZnSO4 @ 20 kg/ha increased significantly the green fodder yield (25.89 t/ha). Interaction effect of phosphorus and zinc application was found significant with respect to green fodder, dry matter yield and nutrient uptake. Yield, phosphorus and zinc uptake in cowpea fodder were showing declining trend at combination of application rate more than 60 kg/ha P2O5 and 20 kg/ha ZnSO4.

An effective strategy to improve grain zinc concentration of winter wheat, Aphids prevention and farmers’ income

Foliar zinc (Zn) application represents an effective way to improve grain Zn concentration of cereal crops. Spraying Zn together insecticides would be an important advantage for the growers to minimize costs. However, there is very little information about combined foliar application of Zn fertilizers together with insecticides. A field experiment was conducted to investigate how spraying Zn fertilizer in form of ZnSO4 together with commonly applied insecticides (e.g., Acetamiprid and Imidacloprid) affects the grain Zn concentration of wheat grown in the Northern China Plain. The main treatment included three levels: only insecticide applied (recorded as T1); foliar Zn fertilizer applied one day after insecticide application (recorded as T2); foliar Zn fertilizer applied together with insecticide (recorded as T3). The results showed that there was no antagonistic effect between insecticide and Zn when they were sprayed together. Compared with insecticide application only, foliar application of Zn fertilizer with insecticide increased grain yield by 3.7–4.9%, and grain Zn density by 48.2–61.6%. Grain yield and grain Zn concentration were not affected no matter Zn fertilizers were applied simultaneously with insecticide or one day after. The toxic effect of insecticide on insects was not affected when it was mixed with Zn fertilizer in the laboratory condition. Compared with application of Zn fertilizer and insecticide at different times, simultaneous combination can reduce the cost by 120 USDha−1 and increase farmers’ net income by 6.3%. Therefore the results show clearly that ZnSO4 can be mixed and sprayed together with insecticide without causing any adverse effect. This is a very useful and cost-effective approach for growers contributing both to improving grain yield and grain Zn concentration and controlling aphids as well.

Exploring the Role of Zinc in Maize (Zea Mays L.) through Soil and Foliar Application

Maize (Zea mays L.) is considered as high nutrient demanding crop and needs balanced nutrition. It is also regarded sensitive to zinc deficiency. Zinc is mostly deficient in soils and application of zinc fertilizer is required to explore its full potential. Crop species and even cultivars within species vary in their Zn requirement. A field experiment was conducted during spring 2011 at Agronomic Research Area, University of Agriculture, Faisalabad, Pakistan to evaluate the comparative efficacy of Zn uptake and grain yield in three maize hybrids (Pioneer-32 F 10, Monsanto-6525 and Hycorn-8288) through the application of Zn in the form of ZnSO4. The ZnSO4 treatments comprised; soil application at the time of sowing @ 12 kg ha-1, foliar application at vegetative stage (9 leaf stage) @ 1% ZnSO4 solution and foliar application at reproductive stage (anthesis) @ 1% ZnSO4 solution and one treatment was kept as a control. The experimental results showed substantial difference in yield and yield contributing parameters such as plant population at harvest, number of grains per cob, biological yield, grain yield and harvest index. Statistically maximum grain yield (8.76t ha-1) was obtained with foliar spray of ZnSO4 at 9-leaf stage (Zn2) in case of Monsanto-6525. Foliar spray of ZnSO4 increased 38% and soil application gave 23.7% more grain yield than control treatment. Foliar spray of ZnSO4 at 9-leaf stage in Monsanto-6525 hybrid produced higher grain yield and net field benefit. Thus foliar application of Zn fertilizers has a positive effect on economic and biological yield of maize crop.

Effect of Phosphorus and Zinc Application on Nutritional Characteristics of Fodder Cowpea (Vigna unguiculata)

An experiment consisting of four phosphorus levels (0, 40, 60 and 80 kg/ha P2O5) and five zinc levels (0, 10, 20, 30 and 40 kg/ha ZnSO4) was laid out in factorial randomized block design to find out the effect on yield and nutritive value of fodder cowpea (Vigna unguiculata). Application of 60 kg/ha phosphorus recorded 27.64 t/ha yield which was 7.50 and 55.6% higher than 40 kg/ha and no phosphorus application, respectively. Application of Zn in the form of ZnSO4 @ 20 kg/ha increased (P<0.05) the green fodder yield (25.89 t/ha). The successive increase in P level from 0 to 60 kg P2O5/ha enhanced CP level significantly (P<0.05) from 15.07 to 17.97%. Zinc application also increased CP content from 15.23 to 17.56% with increase in ZnSO4 level from 0 to 20 kg/ha. The content of NDF and ADF were not influenced due to application of Zn and P. The interaction effects of P and Zn were found to be significant (P<0.05) with respect to P and Zn concentration. P and Zn content in cowpea fodder showed declining trend at application rate more than 60 kg/ha P2O5 and 20 kg/ha ZnSO4. Therefore, a combination of 60 kg/ha P2O5 and 20 kg/ha ZnSO4 could be applied to obtain better yield and nutritive value of fodder cowpea.

Morphological, biochemical and molecular characterization of twelve nitrogen-fixing bacteria and their response to various zinc concentration.

Background:Zinc is an essential micronutrient used in the form of zinc sulfate in fertilizers in the agriculture production system. Nitrogen-fixing microorganisms are also of considerable value in promoting soil fertility.Objectives:This study aimed to investigate the degree of sensitivity to varying concentrations of zinc, in the form of ZnSO4, in different strains of Azotobacter chroococcum in a laboratory environment.Materials and Methods:To isolate A. chroococcum strains, soil samples were collected from wheat, corn and asparagus rhizospheres and cultured in media lacking nitrogen at 30˚C for 48 hours. Strains were identified based on morphological and biochemical characteristics. The presence of the nitrogenase enzyme system was confirmed by testing for the presence of the nifH gene using PCR analysis. The minimum inhibitory concentration (MIC) and optimal zinc concentration for the growth of each strain was determined.Results:A total of 12 bacterial strains were isolated from six different soil samples. A. chroococcum strains were morphologically and biochemically characterized. The presence of the nifH gene was confirmed in all the strains. MIC and the optimal zinc concentration for bacterial growth were 50 ppm and 20 ppm, respectively.Conclusions:It was concluded that increasing the concentration of zinc in the agricultural soil is harmful to beneficial microorganisms and reduces the soil fertility. A 20-ppm zinc concentration in soil is suggested to be optimal.