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1.
Summary A comparison of different zinc carriers showed that application of Zn-DTPA, Zn-EDTA, Zn-fulvate and ZnSO4 significantly increased the dry matter yield and zinc uptake by corn over the control treatment where no zinc was applied. The chelates in particular enhanced to a greater extent the uptake of both native and applied sources than that observed with ZnSO4 as the zinc carrier. Both the dry matter yield and zinc uptake by corn showed a positive and significant relationship with self-diffusion coefficient of zinc showing thereby that diffusion contributed mainly the supply of Zn from the ambient soil matrix to plant roots. The effectiveness of the chelates varied depending on their capacity to retain Zn in a soluble form in the soil solution.It is evident that zinc nutrition of plants in alkaline and calcareous soils can be more effectively regulated by both synthetic and natural chelates or organic manures which contain substantial amount of complexed zinc.Journal Paper No. 1 from the Department of Soil Science and Agric. Chemistry, Tirhut College of Agriculture, Dholi, Muzaffarpur, Bihar, India.  相似文献   

2.
Summary Application of zinc sulphate mixed with compost/poultry manure proved to be equivalent to the effect of dipping the seedling roots in 4% ZnO suspension with respect to rice yields but Zn-amended organic manures were superior to other treatments with regards to total Zn uptake. A marked residual effect of soil applied treatments was recorded on the succeeding maize crop. Application of poultry manure alone was about one and a half times more effective than compost alone in increasing the rice and maize grain yields. Poultry manure surpassed compost in increasing zinc uptake by the crops and at the same time it built up more available Zn in soil than compost for the following crop. The magnitude of yields and Zn uptake response were magnified when zinc sulphate was applied along with organic manures. Application of 25 kg zinc sulphate/ha alone had the same effect as 50 quintals poultry manure alone or 12.5 kg zinc sulphate applied with 50 quintals compost/ha with respect to crop yields. A significant positive correlation was, recorded in both the crops between Zn concentration in grain or straw and their respective yields.  相似文献   

3.
This experiment was conducted to investigate the effects of zinc sulfate and zinc methionine (Zn-Met) and their levels on apoptosis induced by glucocorticoid of thymocytes and the possible mechanism. Dexamethasone was used to make the apoptosis model of thymocytes; zinc sulfate and zinc methionine were supplemented to the medium at levels of 0,50, 100, 500, and 1000 μM. The activity of cells,Cu,Zn superoxide dismutase (Cu,Zn-SOD), DNA ladder pattern, intracellular calcium concentration, and the percentage of apoptosis nuclei were determined. Both ZnSO4 and Zn-Met could modulate apoptosis; they inhibited apoptosis and decreased DNA fragmentation. The regulation was concentration dependent. At levels of 50 and 100 μM, the effect of Zn-Met on inhibiting apoptosis was less efficient than that of ZnSO4 (p<0.05), but the activity of the cells cultured with Zn-Met was higher than those cultured with ZnSO4; they showed no difference in modulating apoptosis when added at levels of 500 and 1000 μM to the medium (p>0.05). Intracellular calcium concentrations of cells cultured with Zn-Met were higher than those cultured with ZnSO4 at the same levels. Zinc supplementation decreased the concentration of intracellular calcium significantly (p<0.05) and increased the activity of Cu,Zn-SOD in the extract of the cells (p<0.05). Both zinc sulfate and Zn-Met could modulate apoptosis of thymocytes induced by glucocorticoid; the mechanism might involve the exchange of intracellular calcium, the redox of cells, and the two forms of zinc might go different ways in the regulations.  相似文献   

4.
Summary Several Zn-deficient soils from the major rice growing areas in the USA were characterized with respect to extractable and labile Zn and other parameters including available P, pH, organic matter, and cation exchange capacity. A greenhouse experiment was conducted to determine whether the above factors influence the response of several rice cultivars to ZnSO4 or ZnEDTA applied as a mixed preplant treatment or to the floodwater at panicle initiation.Response of the rice to Zn varied widely among soils with labile Zn (L value) being a poor indicator of Zn availability and soil pH, and DTPA or 2 N MgCl2 extraction of Zn being the most reliable indices. Soil incorporation prior to flooding was more effective than floodwater application for the initial crop, but both methods of placement were comparable for a subsequent ratoon crop. In either situation, ZnSO4 was superior to ZnEDTA. Recovery of Zn from ZnSO4 was generally less than 5 percent where Zn response was obtained and up to 14 percent from nonresponsive soils.  相似文献   

5.
The toxicity of sporidesmin to rats fed diets containing either 4 ppm or 200 ppm Zn was determined. The high zinc diet doubled the LD50 level for sporidesmin given as a single dose, but the LD50 dose for rats on a zinc deficient diet was not significantly different from that for rats on a diet containing zinc at levels sufficient for normal growth. Subsequent trials demonstrated that large doses of ZnSO4 given orally protected rats from sporidesmin poisoning. The protection was short lived as zinc needed to be given at or soon after sporidesmin challenge.  相似文献   

6.
Summary A field experiment was conducted at Agricultural Research Institute, Dholi during Rabi 1976–77 in sandy loam soil to study the interaction between zinc and potash in wheat. Zinc and potash were applied to the soil in the form of ZnSO4 and KCl respectively. Interaction between zinc and potash was found significant. Both the levels of zinc sulphate 12.5 kg/ha and 25 kg/ha being at par produced significantly higher grain yield over control. There was significant increase in grain yield with application of 40 kg and 80 K2O/ha over control. Potash at the rate of 120 kg in combination with 25 kg Zinc sulphate/ha decreased the yield.  相似文献   

7.
To gain more insight into the impact of zinc on the primary metabolites in rapeseed, plants were regenerated in vitro in the presence of zinc (0.1–1 mM), acclimatized, transferred to a greenhouse, and treated with 2 mM ZnSO4. The main metabolites, including soluble carbohydrates and free amino acids, were analyzed by nuclear magnetic resonance spectroscopy, and further confirmed by spectrophotometry and enzymatic analyses. Exposure of these greenhouse-grown plants to ZnSO4 led to both a significant rise of the total amino acid level and an increase of proline accumulation in the different tissues. Moreover, the control plants, regenerated without zinc stress, exhibited a significant reduction of soluble carbohydrate levels, whereas the plants derived from Zn-treated regenerants exhibited significantly higher levels of both glucose and sucrose. These levels increased proportionally with the Zn concentration in the regeneration step.  相似文献   

8.
Ground rubber contains 15?C20 g Zn kg?1 but very low levels of Cd and could serve as an inexpensive byproduct Zn fertilizer. The aim of this investigation was to test Zn release in a soil treated with ground tire rubber and rubber ash compared with commercial Zn fertilizer and a laboratory grade zinc sulfate. A Zn-deficient soil was chosen from wheat fields in Isfahan province, central Iran, and the ground rubber, rubber ash and fertilizer-Zn and laboratory ZnSO4 were added at 0.5 and 2 mg Zn kg?1; 0.5 kg ha?1 would usually correct Zn deficiency in such pot tests. The soil DTPA-extractable Zn was then measured with time and the results were described examining first order, Elovich, power function and parabolic diffusion kinetics models. In the pot experiment, corn (Zea mays L.) plants were exposed to three rates of Zn (0, 20, 40 mg Zn kg?1) from two different sources (ZnSO4 and ground rubber). Ground rubber was applied as 2?C3 mm and <1 mm diameter particles. Zinc treatments were mixed with the soils before planting. At harvest, concentrations of Zn, Pb, and Cd in roots and shoots of corn were measured. Results showed that ground rubber and rubber ash significantly increased the concentration of DTPA-Zn in the soil and this increase was higher than achieved with the commercial Zn fertilizer. At the lower Zn application rate, Zn release followed parabolic diffusion, while at the higher rate the kinetics of release followed power function and Elovich models. There was an increase in Zn concentration of corn shoot and roots by adding of Zn regardless the source of applied Zn. With increase in the rate of rubber used, the shoot Zn uptake increased. The Pb concentration of shoot and Cd concentrations of shoot and roots were low (less than 0.02 mg kg?1) in all treatments. The results showed that the soil DTPA Zn decreases over time if the soil is amended with a soluble form of Zn whereas the reverse was observed if the Zn is added as ground rubber which only gradually transforms. Thus ground rubber and rubber ash offer strong value as Zn fertilizer for Zn deficient soils.  相似文献   

9.
Taurine and zinc exert neurotrophic effects. Zinc modulates Na+/Cl-dependent transporters. This study examined the effect of zinc (ZnSO4) ex vivo and zinc chelator N,N,N′,N′-tetrakis-(2-pyridylmethyl) ethylenediamine (TPEN) in vivo on [3H]taurine transport in goldfish retina. The effect of TPEN in vivo on taurine and zinc levels was determined. Isolated cells were incubated in Ringer with zinc (0.1–100 μM). Taurine transport was done with taurine (0.001–1 mM) and 50 nM [3H]taurine. Zinc (100 μM) noncompetitively inhibited taurine transport. TPEN was administered intraocularly and retinas extracted 3, 5 and 10 days later. Taurine was determined by HPLC (nmol/mg protein) and zinc by spectrophotometry ICP (mg/mg protein). Taurine and zinc levels decreased at 3 days and increased at 10 days after TPEN administration. At 10 days after intraocular TPEN, taurine transport affinity increased (K s = 0.018 ± 0.006 vs. 0.028 ± 0.008 mM). Apparently, zinc deficiency affects the taurine–zinc complex and taurine availability. The increased taurine uptake affinity by TPEN was possibly associated with a response to maximize retinal taurine content at low zinc concentration.  相似文献   

10.
Summary Greenhouse and laboratory studies were conducted to study the effect of zinc sources and methods of application on correcting zinc deficiency in flooded rice grown on Vertisol from Ngala, northern Nigeria, using the variety IR-20.Plant dry matter yield was similar for ZnSO4, ZnEDTA, metallic Zn and fritted Zn with mixed soil application. Zinc uptake was affected in the following order; ZnSO4 > ZnEDTA > metallic Zn > fritted Zn. Comparable dry matter yield and zinc uptake were obtained with mixing, surface broadcasting and banding of ZnEDTA. Mixing the fritted Zn gave higher dry matter yield and zinc uptake than broadcasting or banding.Seed soaking with a suspension of fritted Zn resulted in higher dry matter yield and zinc uptake than with ZnEDTA solution. Seed soaking for 24 hours with fritted Zn suspension at a concentration of about 0.5 per cent Zn appeared to be a suitable method for applying zinc with direct seeded rice.  相似文献   

11.
Summary In a field experiment, more than 22% increase in the grain yield of corn was obtained by the application of 50 kg ZnSO4/ha. Grain yields were also increased by increasing the level of applied phosphorus. Positive relationship was obtained between Zn and P, the phosphorus treatment increased Zn uptake by grains and vice versa.  相似文献   

12.
Synchrotron-based X-ray absorption fine structure (XAFS) spectroscopy is not widely used in animal science. The objective of this study was to employ the XAFS technique to determine changes in zinc absorption and concentrations in the sheep interstinal sac using different zinc sources. Forty-eight sheep were slaughtered and their duodena were dissected. The duodena were randomly assigned to six zinc sources (ZnO, ZnSO4, ZnMet, ZnLys, ZnSO4 + methionine, ZnSO4 + lysine). Ten centimeters of duodenal sac midpiece was incubated for 40 min in vitro using the everted intestinal sac technique in culture medium containing zinc from different sources. The amount of zinc present was normalized to 4 mg. XAFS was used to analyze the relative concentration and oxidation state of zinc, and atomic absorption spectrometry (AAS) was used to verify zinc concentration. The results showed that, for increasing zinc concentrations, organic zinc was a better source than inorganic zinc. In addition, the zinc concentration achieved using ZnMet was higher than that for ZnO and ZnSO4 (P < 0.05) as measured by atomic absorption spectroscopy. The results using XAFS were consistent with that of AAS. The states of organic zinc and inorganic zinc were identical after being incubated for 40 min. As observed in these experiments, organic zinc was more easily absorbed than inorganic zinc. Our data demonstrate that organic zinc was dissociated into ions and then absorbed as inorganic zinc. In our experiments, we are the first investigators to use XAFS spectroscopy to determine zinc absorption in the sheep duodenal wall. We observed reduced absorption of inorganic zinc in the presence of methionine or lysine. Taken together, we postulate that the optimal molar ratio of inorganic zinc and ligand requires further study.  相似文献   

13.
Brassica rapa L. is an important vegetable crop in eastern Asia. The objective of this study was to investigate the genetic variation in leaf Zn, Fe and Mn accumulation, Zn toxicity tolerance and Zn efficiency in B. rapa. In total 188 accessions were screened for their Zn-related characteristics in hydroponic culture. In experiment 1, mineral assays on 111 accessions grown under sufficient Zn supply (2 μM ZnSO4) revealed a variation range of 23.2–155.9 μg g−1 dry weight (d. wt.) for Zn, 60.3–350.1 μg g−1 d. wt. for Fe and 20.9–53.3 μg g−1 d. wt. for the Mn concentration in shoot. The investigation of tolerance to excessive Zn (800 μM ZnSO4) on 158 accessions, by using visual toxicity symptom parameters (TSPs), identified different levels of tolerance in B. rapa. In experiment 2, a selected sub-set of accessions from experiment 1 was characterized in more detail for their mineral accumulation and tolerance to excessive Zn supply (100 μM and 300 μM ZnSO4). In this experiment Zn tolerance (ZT) determined by relative root or shoot dry biomass varied about 2-fold. The same six accessions were also examined for Zn efficiency, determined as relative growth under 0 μM ZnSO4 compared to 2 μM ZnSO4. Zn efficiency varied 1.8-fold based on shoot dry biomass and 2.6-fold variation based on root dry biomass. Zn accumulation was strongly correlated with Mn and Fe accumulation both under sufficient and deficient Zn supply. In conclusion, there is substantial variation for Zn accumulation, Zn toxicity tolerance and Zn efficiency in Brassica rapa L., which would allow selective breeding for these traits.  相似文献   

14.
Forty weaned male guinea pigs of 208.20±6.62 g mean body weight were divided into 4 groups of 10 animals in a randomized block design. All of the guinea pigs were fed a basal diet [25% ground maize hay, 30% ground maize grain, 22% ground chickpea (Cicer arietinum L.), 9.5% deoiled rice bran, 6% soybean meal, 6% fish meal, 1.45% mineral supplement (without Zn) and 0.05% ascorbic acid] and available green fodder. Group I served as the control (no Zn supplementation), whereas 20 ppm Zn was added in the diet in groups II, III, and IV either as zinc sulfate (ZnSO4), zinc amino acid complex (ZAAC), and ZnSO4 + ZAAC in equal parts, respectively. Experimental feeding lasted for 70 d, including a 3-d digestibility trial. Blood was collected through cardiac puncture from four animals in each group at d 0 and subsequently at the end of experimental feeding. After 40 d of experimental feeding, four animals from each group were injected with 0.4 mL of Brucella abortus cotton strain-19 vaccine to assess the humoral immune response of the animals. After 10 wk of study, four animals from each group were sacrificed to study the concentration of Zn, Cu, Co, Fe, and Mn in the liver, pancreas and spleen. Results revealed no significant difference in the feed intake, body weight gain, and digestibility of the nutrients, except for crude protein (CP) digestibility, which was significantly (p<0.05) lower in group IV. Although concentrations of serum glucose, Ca, and P and the albumin:globulin (A:G) ratio were similar in the different groups, the total protein, albumin, and serum alkaline phosphatase activity were higher in all of the Zn-supplemented groups on d 70. The serum Zn levels at the end of experimental feeding were significantly higher in groups II and III, whereas serum Mn levels were found to be significantly (p<0.05) higher in groups III and IV. The organ weights (as percentage of body weights) did not show any differences among the treatment groups. Although the Mn concentration was significantly (p<0.05) higher in the pancreas, the Cu concentration was significantly (p<0.05) reduced in the spleen in all of the Zn-supplemented groups. The humoral immune response (antibody titer values) on d 14 of vaccination was significantly (p<0.05) higher in all of the Zn-supplemented groups. It was concluded that the 20-ppm level of Zn in the diet might be adequate for growth and nutrient utilization in guinea pigs, but supplementation of 20-ppm zinc significantly improved the immune response and impact was more prominent with the ZAAC (organic source) compared to ZnSO4 (inorganic source).  相似文献   

15.
Erenoglu  B.  Nikolic  M.  Römheld  V.  Cakmak  I. 《Plant and Soil》2002,241(2):251-257
Using two bread wheat (Triticum aestivum) and two durum wheat (Triticum durum) cultivars differing in zinc (Zn) efficiency, uptake and translocation of foliar-applied 65Zn were studied to characterize the role of Zn nutritional status of plants on the extent of phloem mobility of Zn and to determine the relationship between phloem mobility of Zn and Zn efficiency of the used wheat cultivars. Irrespective of leaf age and Zn nutritional status of plants, all cultivars showed similar Zn uptake rates with application of 65ZnSO4 to leaf strips in a short-term experiment. Also with supply of 65ZnSO4 by immersing the tip (3 cm) of the oldest leaf of intact plants, no differences in Zn uptake were observed among and within both wheat species. Further, Zn nutritional status did not affect total uptake of foliar applied Zn. However, Zn-deficient plants translocated more 65Zn from the treated leaf to the roots and remainder parts of shoots. In Zn-deficient plants about 40% of the total absorbed 65Zn was translocated from the treated leaf to the roots and remainder parts of shoots within 8 days while in Zn-sufficient plants the proportion of the translocated 65Zn of the total absorbed 65Zn was about 25%. Although differences in Zn efficiency existed between the cultivars did not affect the translocation and distribution of 65Zn between roots and shoots. Bread wheats compared to durum wheats, tended to accumulate more 65Zn in shoots and less 65Zn in roots, particularly under Zn-deficient conditions. The results indicate that differences in expression of Zn efficiency between and within durum and bread wheats are not related to translocation or distribution of foliar-applied 65Zn within plants. Differential compartementation of Zn at the cellular levels is discussed as a possible factor determining genotypic variation in Zn efficiency within wheat.  相似文献   

16.
The effects of chromium (chromium picolinate, CrPic) and zinc (ZnSO4H2O) supplementation on serum concentrations of malondialdehyde (MDA) (an indicator of lipid peroxidation) and serum status of some antioxidant vitamins and minerals of laying hens (Hy-Line) reared at a low ambient temperature (6.8°C) were evaluated. One hundred twenty laying hens (Hy-Line; 32 wk old) were divided into 4 groups, 30 hens per group. The hens were fed either a basal diet or the basal diet supplemented with either 0.4 mg Cr/kg of diet, 30 mg Zn/kg of diet, or 0.4 mg Cr plus 30 mg Zn/kg of diet. Digestibility of nutrients (dry matter [DM], organic matter [OM], crude protein [CP], and ether extract [EE]) increased by supplementation of chromium and zinc (p<0.05). Supplemental chromium and zinc increased serum vitamins C and E but decreased MDA concentrations (p<0.05). Additionally, supplemental chromium and zinc caused an increase in the serum concentrations of Fe, Zn, Mn, and Cr (p < 0.05). The present study showed that low ambient temperature causes detrimental effects on the digestibility of nutrients and antioxidant status and that such detrimental effects caused by low ambient temperature can be alleviated by chromium and zinc supplementation, particularly when Cr and Zn were simultaneously included into the diet. Data obtained in the present study suggest that such supplementation can be considered as a protective management practice in a diet of laying hens for alleviating negative effects of cold stress.  相似文献   

17.
The element Zn is the metal component or activator of many important enzymes. The tissue concentrations and activities of Zn metalloenzymes direct the rate of protein and nucleic acid syntheses, thereby influencing tissue growth and reperative processes. Most of the serum Zn is normally bound to circulating proteins. Low serum Zn concentrations might result from depletion of Zn-binding proteins. Serum protein and Zn concentrations have been reported to be depressed in patients with acute and chronic diseases. We compare the serum protein and Zn values of patients with thoracic empyema (n=20) with those of a control group (n=20). The values obtained in the empyema group were significantly lower than those in the control group before the study. Test group administered 220 mg zinc sulfate (ZnSO4. 7H2O) over 20 d and there was a significant increase in the values for serum protein and Zn after the oral administration of the zinc sulfate.  相似文献   

18.
Kouya Yamaki  Shin Yoshino 《Biometals》2009,22(6):1031-1040
The effects of ultrafine and fine particles of zinc oxide (ZnO) on IgE-dependent mast cell activation were investigated. The rat mast cell line RBL2H3 sensitized with monoclonal anti-ovalbumin (OVA) IgE was challenged with OVA in the presence or absence of ZnO particles and zinc sulfate (ZnSO4). Degranulation of RBL2H3 was examined by the release of β-hexosaminidase. To understand the mechanisms responsible for regulating mast cell functions, the effects of ZnO particles on the levels of intracellular Zn2+, Ca2+, phosphorylated-Akt, and global tyrosine phosphorylation were also measured. IgE-induced release of β-hexosaminidase was obviously attenuated by ultrafine ZnO particles and ZnSO4, whereas it was very weakly inhibited by fine ZnO particles. The intracellular Zn2+ concentration was higher in the cells incubated with ultrafine ZnO particles than in those with fine ZnO particles. Consistent with inhibitory effect on release of β-hexosaminidase, ultrafine ZnO particles and ZnSO4, but not fine ZnO particle, strongly attenuated the IgE-mediated increase of phosphorylated-Akt and tyrosine phosphorylations of 100 and 70 kDa proteins in RBL2H3 cells. These findings indicate that ultrafine ZnO particles, with a small diameter and a large total surface area/mass, could release Zn2+ easily and increase intracellular Zn2+ concentration efficiently, thus decreasing FcεRI-mediated mast cell degranulation through inhibitions of PI3K and protein tyrosine kinase activation. Exposure to ZnO particles might affect immune responses, especially in allergic diseases.  相似文献   

19.
Summary Zinc adsorption was studied in suspensions of six soils of different physicochemical characteristics in dilute ZnSO4 solutions. At low concentrations, Zn2+ adsorption was described by the Langmuir adsorption equation. The calculated Langmuir adsorption maxima were related positively to clay and carbonate content and negatively with organic matter content of soils. Multiple regression analysis revealed that zinc adsorption maxima can be predicted with good precision from information in soil survey reports. When the added Zn2+ exceeded the adsorption maximum, the solid phase of zinc controlling its concentration in solution was either zinc hydroxide or carbonate so long as soil carbonates were present. The values of zinc potential also indicated that soils retain Zn2+ more strongly than Zn(OH)2 or carbonate. Postgraduate student Professor of Soils. Professor of Soils.  相似文献   

20.
In the current study, antidiabetic activity and toxic effects of zinc oxide nanoparticles (ZnO) were investigated in diabetic rats compared to zinc sulfate (ZnSO4) with particular emphasis on oxidative stress parameters. One hundred and twenty male Wistar rats were divided into two healthy and diabetic groups, randomly. Each major group was further subdivided into five subgroups and then orally supplemented with various doses of ZnO (1, 3, and 10 mg/kg) and ZnSO4 (30 mg/kg) for 56 consecutive days. ZnO showed greater antidiabetic activity compared to ZnSO4 evidenced by improved glucose disposal, insulin levels, and zinc status. The altered activities of erythrocyte antioxidant enzymes as well as raised levels of lipid peroxidation and a marked reduction of total antioxidant capacity were observed in rats receiving ZnO. ZnO nanoparticles acted as a potent antidiabetic agent, however, severely elicited oxidative stress particularly at higher doses.  相似文献   

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