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1.
Sutter B Taylor RE Hossner LR Ming DW 《Soil Science Society of America journal. Soil Science Society of America》2002,66(2):455-463
The incorporation of micronutrients into synthetic hydroxyapatite (SHA) is proposed for slow release of these nutrients to crops in the National Aeronautics and Space Administration's (NASA's) Advanced Life Support (ALS) program for Lunar or Martian outposts. Solid state 31P nuclear magnetic resonance (NMR) was utilized to examine the paramagnetic effects of Fe3+, Mn2+, and Cu2+ to determine if they were incorporated into the SHA structure. Separate Fe3+, Mn2+, and Cu2+ containing SHA materials along with a transition metal free SHA (pure-SHA) were synthesized using a precipitation method. The proximity (<1 nm) of the transition metals to the 31P nuclei of SHA were apparent when comparing the integrated 31P signal intensities of the pure-SHA (87 arbitrary units g-1) with the Fe-, Mn-, and Cu-SHA materials (37-71 arbitrary units g-1). The lower integrated 31P signal intensities of the Fe-, Mn-, and Cu-SHA materials relative to the pure-SHA suggested that Fe3+, Mn2+, and Cu2+ were incorporated in the SHA structure. Further support for Fe3+, Mn2+, and Cu2+ incorporation was demonstrated by the reduced spin-lattice relaxation constants of the Fe-, Mn-, and Cu-SHA materials (T'=0.075-0.434s) relative to pure-SHA (T1=58.4s). Inversion recovery spectra indicated that Fe3+, Mn2+, and Cu2+ were not homogeneously distributed about the 31P nuclei in the SHA structure. Extraction with diethylene-triamine-penta-acetic acid (DTPA) suggested that between 50 and 80% of the total starting metal concentrations were incorporated in the SHA structure. Iron-, Mn-, and Cu-containing SHA are potential slow release sources of Fe, Mn, and Cu in the ALS cropping system. 相似文献
2.
Sutter B Ming DW Clearfield A Hossner LR 《Soil Science Society of America journal. Soil Science Society of America》2003,67(6):1935-1942
The National Aeronautics and Space Administration's (NASA) Advanced Life Support (ALS) Program is evaluating the use of Fe-, Mn-, and Cu-containing synthetic hydroxyapatite (SHA) as a slow release fertilizer for crops that might be grown on the International Space Station or at Lunar and Martian outposts. Separate Fe-, Mn-, and Cu-containing SHA materials along with a transition-metal free SHA (pure-SHA) were synthesized using a precipitation method. Chemical and mineralogical analyses determined if and how Fe, Mn, and Cu were incorporated into the SHA structure. X-ray diffraction (XRD), Rietveld refinement, and transmission electron microscopy (TEM) confirmed that SHA materials with the apatite structure were produced. Chemical analyses indicated that the metal containing SHA materials were deficient in Ca relative to pure-SHA. The shift in the infrared PO4-mu 3 vibrations, smaller unit cell parameters, smaller particle size, and greater structural strain for Fe-, Mn-, and Cu-containing SHA compared with pure-SHA suggested that Fe, Mn, and Cu were incorporated into SHA structure. Rietveld analyses revealed that Fe, Mn, and Cu substituted into the Ca2 site of SHA. An Fe-rich phase was detected by TEM analyses and backscattered electron microscopy in the Fe-containing SHA material with the greatest Fe content. The substitution of metals into SHA suggests that metal-SHA materials are potential slow-release sources of micronutrients for plant uptake in addition to Ca and P. 相似文献
3.
Sutter B Hossner LR Ming DW 《Soil Science Society of America journal. Soil Science Society of America》2005,69(2):362-370
Micronutrient-substituted synthetic hydroxyapatite (SHA) is being evaluated by the National Aeronautics and Space Administration's (NASA) Advanced Life Support (ALS) Program for crop production on long-duration human missions to the International Space Station or for future Lunar or Martian outposts. The stirred-flow technique was utilized to characterize Ca, P, Fe, Mn, and Cu release characteristics from Fe-, Mn-, and Cu-containing SHA in deionized (DI) water, citric acid, and diethylene-triamine-pentaacetic acid (DTPA). Initially, Ca and P release rates decreased rapidly with time and were controlled by a non-SHA calcium phosphate phase(s) with low Ca/P solution molar ratios (0.91-1.51) relative to solid SHA ratios (1.56-1.64). At later times, Ca/P solution molar ratios (1.47-1.79) were near solid SHA ratios and release rates decreased slowly indicating that SHA controlled Ca and P release. Substituted SHA materials had faster dissolution rates relative to unsubstituted SHA. The initial metal release rate order was Mn > Cu > Fe which followed metal-oxide/phosphate solubility suggesting that poorly crystalline metal-oxides/phosphates were dominating metal release. Similar metal release rates for all substituted SHA (approximately 0.01 cmol kg-1 min-1) at the end of the DTPA experiment indicated that SHA dissolution was supplying the metals into solution and that poorly crystalline metal-oxide/phosphates were not controlling metal release. Results indicate that non-SHA Ca-phosphate phases and poorly crystalline metal-oxide/phosphates will contribute Ca, P, and metals. After these phases have dissolved, substituted SHA will be the source of Ca, P, and metals for plants. 相似文献
4.
A. S. Mangrich A. W. Lermen E. J. Santos R. C. Gomes R. R. R. Coelho L. F. Linhares N. Senesi 《Biology and Fertility of Soils》1998,26(4):341-345
The coordination chemistry of iron (III) (Fe3+) and copper (II) (Cu2+) in melanins synthesized by seven actinomycetes isolated from Brazilian latosol soils under savanna (cerrado) vegetation
was investigated using electron paramagnetic resonance (EPR) and ultraviolet-visible (UV-Vis) spectroscopy. The EPR spectra
indicated the presence of Cu2+ ions bound to oxygenated and nitrogenous functional groups, and rhombic coordinated Fe3+ ions. In some of the actinomycete melanins the EPR hyperfine splitting of Cu+2 ion complexes was well resolved, and indicated four magnetically equivalent nitrogen atoms in a plane. This result suggested
the presence of Cu+2 porphyrin complexes, which was confirmed by Soret bands in the 400-nm region of the UV-Vis spectra. The concentration of
Mn in actinomycete melanins, determined by inductively coupled plasma atomic emission spectroscopy, was lower than those of
Cu and Fe.
Received: 9 April 1997 相似文献
5.
外源EBR对NaCl胁迫下紫花苜蓿幼苗微量元素
吸收及叶绿素荧光动力学参数的影响 总被引：1，自引：0，他引：1
为明确外源2,4-表油菜素内酯(2,4-epibrassinolide,EBR)诱导紫花苜蓿(Medicago sativa L.)幼苗抗盐性的效果及其可能的生理调节机制,采用营养液水培法,以紫花苜蓿品种‘中苜3号’和‘陇中苜蓿’为材料,研究Na Cl胁迫下施用外源EBR对紫花苜蓿幼苗微量元素吸收及叶片PSⅡ功能、电子传递速率和光能分配的影响。结果表明:150 mmol·L~(-1) Na Cl胁迫下,苜蓿幼苗不同器官(叶片、茎秆、根系)中的Cu~(2+)含量显著升高,Fe~(2+)、Mn~(2+)、Zn~(2+)含量和Fe~(2+)/Na+、Mn~(2+)/Na+、Cu~(2+)/Na+、Zn~(2+)/Na+显著降低,无机离子的吸收、运输和分配等代谢平衡被打破;同时Na Cl胁迫造成苜蓿幼苗叶片PSⅡ反应中心受损,天线耗散、反应中心耗散增加,光合能力下降。Na Cl胁迫下,施用0.1μmol·L~(-1)外源EBR后,苜蓿幼苗不同器官(叶片、茎秆、根系)中的Cu~(2+)含量显著降低,Fe~(2+)、Mn~(2+)、Zn~(2+)含量及Fe~(2+)/Na+、Mn~(2+)/Na+、Cu~(2+)/Na+、Zn~(2+)/Na+显著升高,幼苗体内无机离子的吸收、运输得到有效调控,Na+和Fe~(2+)、Mn~(2+)、Cu~(2+)、Zn~(2+)等阳离子间的拮抗作用减小;苜蓿幼苗叶片的F_0、NPQ显著降低,F_m、F_v/F_0、F_v/F_m、ФPSⅡ、F_v′/F_m′、q P和ETR显著升高,苜蓿幼苗叶片吸收的光能用于光化学反应部分(P)增加、天线色素耗散部分(D)和反应中心过剩光能部分(E)降低。说明外源EBR能够促进Na Cl胁迫下苜蓿幼苗对无机离子的选择性吸收、运输和分配,维持体内的离子代谢平衡,通过提高光合电子传递效率,降低天线热耗散和反应中心过剩光能,维持较高的PSⅡ光化学活性,进而平衡激发能在PSⅠ、PSⅡ之间的分配,降低Na Cl胁迫对PSⅡ反应中心的损伤程度,有效缓解Na Cl胁迫对苜蓿幼苗所造成的伤害。 相似文献
6.
不同金属离子对生物质发酵产氢的影响 总被引：1，自引：1，他引：0
为揭示不同金属离子在生物质发酵产氢中的作用规律,以混合菌群发酵产氢为研究对象,采用正交试验设计的方法,考察了7种金属离子对生物质发酵产氢的影响。通过对不同金属离子质量浓度及相互关系对发酵产氢影响的综合比较,获得以下结论：促进混合菌群发酵产氢的金属离子组成为：Fe2+ 20 mg/L,Zn2+ 0 mg/L,Ni2+ 1 mg/L,Mg2+ 10 mg/L,K+ 100 mg/L,Fe3+ 100 mg/L,Mn2+ 1 mg/L;H2与CO2、总产气量存在显著的正比关系,与糖利用率无直接关系;以PDB（马 相似文献
7.
Characterization of monoclonal antibodies for lead-chelate complexes: applications in antibody-based assays 总被引：4，自引：0，他引：4
Zhu X Hu B Lou Y Xu L Yang F Yu H Blake DA Liu F 《Journal of agricultural and food chemistry》2007,55(13):4993-4998
Monoclonal antibodies against lead were generated by immunizing BALB/c mice with lead conjugated to keyhole limpet hemocyanin (KLH) via a bifunctional chelator, S-2-(4-aminobenzyl)diethylenetriamine pentaacetic acid (DTPA). Stable hybridoma cell lines were produced by fusion of murine splenocytes and SP2/0 myeloma cells. One of the hybridomas generated from this fusion (4/7) synthesized and secreted an antibody that bound tightly to Pb2+-DTPA complexes but not to metal-free DTPA. The performance for a competitive inhibition enzyme-linked immunosorbent assay (ELISA) incorporating this antibody was assessed for its sensitivity to changes in pH, ionic strength, and blocking reagents. The cross-reactivities in this ELISA were less than 3% for Fe3+, Cd2+, Hg2+, and Cu2+ and less than 0.3% for Cr3+, Mn2+, Mg2+, In3+, Ag1+, Ni2+, Co2+, Zn2+, Ca2+, Cu1+, and Hg1+. The IC50 value achieved for lead was 2.72 +/- 0.034 microM, showing the detection range of 0.092-87.2 microM and the lowest detection limit of 0.056 +/- 0.005 microM. Recoveries from the analyte-fortified tap water and ultrapure water were in the range of 80-114% . These results indicate that the ELISA could be a convenient analytical tool for monitoring lead residues in drinking water. 相似文献
8.
氧化/磺化腐殖酸对潮土中Cu、Zn、Fe、Mn有效性的影响 总被引：1，自引：0，他引：1
9.
Iron (Fe) availability is low in calcareous soils of southern Iran. The chelate Fe-ethylenediamine di (o-hydroxy-phenylacetic acid) (Fe-EDDHA), has been used as an effective source of Fe in correcting Fe deficiency in such soils. In some cases, however, its application might cause nutritional disorder due to the antagonistic effect of Fe with other cationic micronutrients, in particular with manganese (Mn). A greenhouse experiment was conducted to evaluate the influence of soil and foliar applications of Fe and soil application of manganese (Mn) on dry matter yield (DMY) and the uptake of cationic micronutrients in wheat (Triticum aestivum L. var. Ghods) in a calcareous soil. Results showed that neither soil application of Fe-EDDHA nor foliar application of Fe sulfate had a significant effect on wheat DMY. In general, Fe application increased Fe uptake but decreased that of Mn, zinc (Zn), and copper (Cu). Application of Mn increased only Mn uptake and had no significant effect on the uptake of the other cationic micronutrients. Iron treatments considerably increased the ratio of Fe to Mn, Zn, Cu, and (Mn + Zn + Cu). Failure to observe an increase in wheat DMY following Fe application is attributed to the antagonistic effect of Fe with Mn, Zn, and Cu and hence, imbalance in Fe to (Mn + Zn + Cu) ratio. Due to the nutritional disorder and imbalance, it appears that neither soil application of Fe-EDDHA nor foliar application of Fe-sulfate is appropriate in correcting Fe deficiency in wheat grown on calcareous soils. Hence, growing Fe-efficient wheat cultivars should be considered as an appropriate practice for Fe chlorosis-prone calcareous soils of southern Iran. 相似文献
10.
As part of a study to determine the magnitude of atmospheric inputs of materials into the lakes of central Ontario, a four-station network of bulk deposition and wet-only precipitation samplers was established in the Muskoka-Haliburton and Sudbury regions to determine the deposition (mg m2? yr?1) and volume weighted concentration (μg 1?1) of Ph, Cu, Ni, Zn, Al, Mn and Fe in precipitation. Large temporal variations in the monthly deposition of all metals were observed. The variations for Cu and Ni exhibited seasonal patterns which could be attributed to a combination of source and wind direction factors. Concentration and deposition of all metals at Muskoka-Haliburton were generally as low or lower than median North American values from the literature. At Sudbury, the large local smelting industry contributed to the elevated Cu, Ni, Zn, and Fe deposition measured in the region (up to two orders of magnitude larger than Muskoka-Haliburton); Al and Mn values were not elevated. Deposition of Cu. Ni and Fe was inversely related to distance from the largest point source at Sudbury. The importance of dry deposition is greatest at Sudbury where dry inputs of Cu, Zn, Al, and Fe generally exceed wet inputs. In contrast, wet deposition of metals at Muskoka-Haliburton predominates over dry. Calculation of an enrichment factor (normalized against Mn) showed that the levels of Pb, Cu, Ni and Zn observed in the precipitation of central Ontario require an additional non-crustal source (either natural or anthropogenic) for explanation. 相似文献
11.
重庆缙云山酸沉降背景下针阔混交林水化学特征初步研究 总被引：1，自引：0，他引：1
选取三峡库区缙云山小流域针阔混交林作为研究对象,对其大气降水、穿透雨、树干茎流、地表径流等水文过程中的pH值及Na+、K+、Ca2+、Mg2+等离子含量进行研究,结果表明:(1)大气降水pH值为5.31,呈酸性,已属于酸雨范围(pH<5.65)。相对于大气降水,针阔混交林穿透雨和树干茎流离子含量均大幅增加。穿透雨和树干茎流中,Mg、Cu元素的变异系数均小于大气降水,而K、Zn和Mn均大于大气降水。地表径流中Ca元素含量最高,为16.416mg/L,Mn元素含量最低,几乎检测不到。各元素含量排序为:Ca>K>Na>Mg>Zn>Fe>Cu>Mn。地下径流中,Ca元素是含量增加最多的养分元素,各元素含量排序为:Ca>K>Na>Mg>Zn>Cu>Fe=Mn。(2)Cu元素在穿透雨和树干茎流中均出现了负淋溶,其余各元素浓度均有所增加。如果林木长期处于酸雨逆境下,将会导致部分营养元素大量流失,并最终造成林木营养亏损且影响其生长。 相似文献
12.
Charles D. Foy Julio C. de Paula Jose A. Centeno Emilia Ivanova Jücker 《Journal of plant nutrition》2013,36(4-5):769-782
Plant genotypes within species differ widely in tolerance to excess manganese (Mn) that may occur in acid soils, or in neutral or alkaline soils having poor aeration caused by imperfect drainage or compaction. However, Mn tolerance mechanisms in plants are largely unknown. Silicon (Si) is reported to detoxify Mn within plants, presumably by preventing localized accumulations of Mn associated with lesions on leaves. Because Mn is paramagnetic, electron paramagnetic resonance (EPR) spectroscopy, shows promise as a tool for characterizing toxic and non‐toxic forms of Mn in tolerant and sensitive plants. The objective of our study was to use EPR to: i) determine the chemical/ physical state of Mn in Mn‐tolerant and ‐sensitive snapbean cultivars; and ii) characterize the protective effects of Si against Mn toxicity. Manganese‐sensitive Wonder Crop 2 (WC) and Mn‐tolerant Green Lord (GL) cultivars of snapbean were grown at pH 5.0, in a greenhouse, in a modified Steinberg solution containing: Mn=0.05mg.L‐1 (optimal); Mn=1.0mgL‐1 (toxic); Mn=1.0 mg L‐1 plus Si=4 mg L‐1; and Mn=0.05 mg L‐1 plus 4 mg Si L‐1. All trifoliate leaf samples exhibited a 6‐line EPR signal that is characteristic of hexaaquo Mn2+. In both cultivars, a higher EPR Mn2+ signal‐intensity generally correlated with lower total leaf mass, higher total Mn concentrations and more pronounced symptoms of toxicity. Tolerance to excess Mn coincided with lower Mn2+ signal intensity. Silicon treatments ameliorated Mn toxicity symptoms in both genotypes, decreased total leaf Mn concentrations, and decreased EPR Mn2+ signal intensity. Results suggest that Mn toxicity is associated with reduced electron transport and accumulation of oxidation products in leaves. Amelioration of Mn toxicity by Si is regarded as connected with a reduction in this Mn‐induced process. Results indicated that EPR spectroscopy can be useful in investigating the biochemical basis for differential Mn tolerance in plants. The EPR observations might also help plant breeders in developing Mn‐tolerant cultivars. 相似文献
13.
铁和不同形态氮素对玉米植株吸收矿质元素及其在体内分布的影响 Ⅱ.对铁、锰、铜、锌等营养元素的影响 总被引：5，自引：0，他引：5
用营养液培养方法研究了铁和两种形态氮素对玉米植株吸收铁、锰、铜、锌等微量元素及其在体内分布的影响。结果表明:与硝态氮(NO3--N)相比,铵态氮(NH4+-N)显著提高了玉米对铁的吸收,降低了对锰、铜及锌的吸收。供铁也明显提高了植株地上部铁的吸收总量,降低了锰及锌的吸收量,尤其是在供应No3--N时这种作用更为明显。在缺铁条件下,NH4+-N处理的玉米新叶中铁的含量明显高于NO3--N处理;而新叶、老叶、茎中锰、锌、铜含量以及根中锰、锌含量都明显低于NO3--N处理。但使用NH4+-N时,根中铜的含量较高。在供铁条件下,NH4+-N处理的玉米植株四个不同器官中锰和锌的含量显著低于NO3--N处理的植株,而铜的含量正好相反。在缺铁条件下,玉米新叶中活性锰、活性锌的含量显著高于供铁处理;与NO3--N相比,NH4+-N的供应也显著降低了玉米新叶中活性锰以及活性锌的含量。 相似文献
14.
伊朗中部伊斯法罕地区土地利用对石灰性土壤磁性质和重金属的空间分布的影响 总被引：10，自引：0，他引：10
Anthropogenic activities have caused the accumulation of heavy metals in the soil environment. Pollution of the soils significantly reduces environmental quality and affects human health. In many recent studies, magnetic susceptibility measurements have been used for pollution monitoring. The objective of this research was to determine the spatial variability of magnetic properties and selected heavy metals and the effects of land use on their variability in the surface soils of the Isfahan region, Central Iran. A total of 158 composite surface (0-5 cm) samples of calcareous soils were collected from an area of about 700 km2, located along a cross-border transect from Isfahan City to a steel plant, covering urban, industrial, agricultural and uncultivated land uses. Concentrations of copper (Cu), zinc (Zn), lead (Pb), manganese (Mn), iron (Fe), nickel (Ni), chromium (Cr), and cobalt (Co) and magnetic parameters, magnetic susceptibility at low frequency (χlf), natural remanent magnetization (NRM), saturation isothermal remanent magnetization (SIRM), and isothermal remanent magnetization at the field of 100 mT (IRM100mT) and the backfield of 100 mT (IRM-100mT), were measured in all the soil samples. Results showed that magnetic susceptibility in the urban and industrial land topsoils (0--5 cm) samples was significantly higher than that in the agricultural and uncultivated land soils in the study area. Concentrations of Cu, Zn, Pb, Mn, and Fe were positively correlated with magnetic properties (χlf, IRM100mT, SIRM, IRM-100mT, and NRM), which could be attributed to their inputs from traffic emissions and industrial activities at the study sites. Ni and Cr concentrations showed significant negative correlations with magnetic properties. No significant correlation was found between Co concentration and magnetic parameters. The Tomlinson pollution load index (PLI) showed significant correlation with the magnetic properties (χlf, IRM100mT, SIRM, IRM-100mT, and NRM). The spatial distribution of the selected heavy metals and χlf in the study area suggested that activities at the urban and industrial land sites caused greater pollution as compared to that at the study sites of other land uses. The concentrations of Cu and Zn seemed to have been affected by anthropogenic sources, whereas Ni, Cr, and Co were mainly controlled by natural sources in the study area. Moreover, the concentrations of soil Pb and Fe in the study area could be affected by both lithologic and anthropogenic sources. The magnetic parameters appeared to be a proxy measure for the degree of heavy metal contamination and could be a potential method for the detection and mapping of contaminated soils. 相似文献
15.
Weekly or half-monthly bulk rainwater samples were collected over 3 yr (1993–1995) at Porspoder, an Atlantic station near Brest, France. They were analyzed for 0.08 M HNO3-leachable trace metals Cd, Cu, Fe, Mn, Ni, Pb and Zn by direct electrothermal atomic absorption spectrometry. Major ions and nitrogen species (NO3- and NH4+) in precipitation were determined by ion chromatography. In coastal precitation, a high correlation was observed for major ions having a seawater origin (Na+, CL- and Mg2+. Zn, Cd, Cu, Ni and Pb were well correlated indicating their anthropogenic origin. In the case of nitrogen species and nssSO42- a high correlation with Zn was observed, taken as an anthropogenic pollution tracer. Major ions and nitrogen species were determined according to wind sector direction showing clearly the impact of the pollution at this station attributed to continental air masses. A relative constancy of pH values in all wind directions was observed. Due to an important oceanic influence, trace metal concentrations and annual deposition densities were significantly lower at Porspoder than at North Sea coastal stations. In the case of nitrogen species, the relatively higher concentration levels probably indicated a significant local agricultural contribution. 相似文献
16.
Bush beans (Phaseolus vulgaris L. cv Contender) were grown on perlite with nutrient solution and 0, 1, 2.5 and 5 ppm levels of Na2CrO4 Significant decrease of top growth and chlorosis in trifoliated leaves were observed for 2.5 and 5 ppm Cr, with Cr concentrations (μg/g) in tops:≥ 12.1, in roots:≥ 509.9. Cr decreased K, Na, Mg and Fe concentrations, and increased P and Mn concentrations in roots. In tops decreased N, K, Na and Fe concentrations and increased Mn and Ca concentrations were observed, Translocation of P, Zn, Cu and Fe was inhibited; Ca and Mn translocation was generally enhanced. P/Fe ratio was increased up to 60% in chlorotic plants, indicating a shift from Fe2+ to Fe3+. 相似文献
17.
Harris WR Sammons RD Grabiak RC Mehrsheikh A Bleeke MS 《Journal of agricultural and food chemistry》2012,60(24):6077-6087
Essential nutrients such as trace metal ions, amino acids, and sugars are transported in the phloem from leaves to other parts of the plant. The major chelating agents in phloem include nicotianamine, histidine, cysteine, glutamic acid, and citrate. A computer model for the speciation of metal ions in phloem has been used to assess the degree to which the widely used herbicide glyphosate binds to Fe(3+), Fe(2+), Cu(2+), Zn(2+), Mn(2+), Ca(2+), and Mg(2+) in this fluid over the pH range of 8 to 6.5. The calculations show that glyphosate is largely unable to compete effectively with the biological chelating agents in phloem. At a typical phloem pH of 8, 1.5 mM glyphosate binds 8.4% of the total Fe(3+), 3.4% of the total Mn(2+), and 2.3% of the total Mg(2+) but has almost no effect on the speciation of Ca(2+), Cu(2+), Zn(2+), and Fe(2+). As the pH decreases to 6.5, there are some major shifts of the metal ions among the biological chelators, but only modest increases in glyphosate binding to 6% for Fe(2+) and 2% for Zn(2+). The calculations also indicate that over 90% of the glyphosate in phloem is not bound to any metal ion and that none of the metal-glyphosate complexes exceed their solubility limits. 相似文献
18.
A. Moreira L. A. C. Moraes D. Navroski 《Communications in Soil Science and Plant Analysis》2017,48(7):792-800
Liming reduces acidity neutralizes aluminum (Al3+) and manganese (Mn2+) toxicities and increases calcium (Ca2+) and magnesium (Mg2+) concentrations in many acid soils of the world. However, it reduces the availability of other cationic micronutrients that are essential for plant growth. Therefore, an experiment was conducted in greenhouse conditions for assessing the effects of higher lime rates in foliar and grain boron (B), copper (Cu), iron (Fe), manganese (Mn), and zinc (Zn) concentrations of 15 soybean genotypes [Glycine max (L) Merrill]. The lime rates were calculated to raise base saturation (V) to 40 and 70%. The soybean genotypes were classified as efficient and moderately efficient in lime-use, the most efficient cultivar was BRS 295RR, and the least efficient was TMG 7161RR and BMX Força RR. The lime rates × genotypes interaction was significant for foliar Cu. The grain the interactions were significant for B, Cu, Fe, and Mn concentrations. Foliar and grain B, Cu, Fe, Mn, and Zn concentrations varied significantly among the genotypes. The Ca and Mg concentrations in the leaf, grain, and soil showed a positive correlation with foliar B concentrations and a negative correlation with leaf and grain Cu, Mn, and Zn concentrations. 相似文献
19.
The presence of ethylenediamine-N-(o-hydroxyphenylacetic)-N'-(p-hydroxyphenylacetic) acid (o,p-EDDHA) as the second largest component in commercial EDDHA iron chelates has recently been demonstrated. Here is reported the speciation of o,p-EDDHA by the application of a novel methodology through the determination of the complexing capacity, protonation, and Ca(2+), Mg(2+), Cu(2+), and Fe(3+) stability constants. The pM values and species distribution in solution, hydroponic, and soil conditions were obtained. Due to the para position of one phenol group in o,p-EDDHA, the protonation constants and Ca and Mg stability constants have different values from those of o,o-EDDHA and p,p-EDDHA regioisomers. o,p-EDDHA/Fe(3+) stability constants are higher than those of EDTA/Fe(3+) but lower than those of o,o-EDDHA/Fe(3+). The sequence obtained for pFe is o,o-EDDHA/Fe(3+) >/= o,p-EDDHA/Fe(3+) > EDTA/Fe(3+). o,p-EDDHA/Fe(3+) can be used as an iron chelate in hydroponic conditions. Also, it can be used in soils with limited Cu availability. 相似文献
20.