Zinc in plants

Clarification of copper interactions with molybdenum, sulfate, iron, and zinc in plant and animal metabolisms (NAS 1977 Eisler 1989, 1993)... 

Zinc in Plant and Animal Nutrition. In 1854 A. Braun discovered the presence of zinc in plants and m 1869 J. Raulin proved diat it is essential for the growth of Aspergillus (153, 154). Its important role in die nutrition of many plants and animals has been demonstrated repeatedly (104, 105). When some pecan tines growing on a copper-deficient soil were treated widi a copper solution, die only trees which responded favorably were those treated with a solution which had been stirred up in a galvanized bucket and therefore contained zinc unintentionally (106). Zinc solutions are now used in the treatment of pecan rosette and other zinc-deficiency diseases of fruit trees and nut-bearing trees in the western states (112). 

In an official method [83] for determining zinc in plant material, the sample is digested with perchloric acid 60% nitric acid 70%, m/v 1 4, followed by 2 M hydrochloric acid. Alternatively, the plant material is dry ashed and the residue dissolved in 6 M hydrochloric acid. The extract is evaluated by AAS at the 213.9 nm emission line. See also Sect. 7.34.1,7.34.4 and 7.34.7. 

Ministry of Agriculture, Lisheries and Lood (1973) The Analysis of Agricultural Materials - Zinc in Plant Material, Method 81, Technical Bulletin RB 427, HMSO, London, UK. 

Holm, P. E., Christensen, T. H., Lorenz, S. E., Hamon, R. E., Domingues, H. C., Sequeira, E. M., and McGrath, S. P. (1998). Measured soil water concentrations of cadmium and zinc in plant pots and estimated leaching outflows from contaminated soils. Water Air Soil Pollut. 102, 105—115. 

Souliotis, A. G. Simultaneous routine determination of copper and zinc in plants by neutron-activation analysis. Analyst 94, 359 (1969)... 

The acquisition of iron, copper, and zinc in plant roots has been described in Chapter 7. Once within the root epidermal cell, the iron must be transported through the roots to the xylem and thence to the leaves, and this intercellular metal transport is illustrated for dicots in Fig. 8.8 and for monocots in Fig. 8.9. In dicots, Fe, Zn, and Cu are taken up into the symplast by transporters in the epidermis. Reduction of Fe and possibly of Cu by FR02 and acidification of the soil by an Arabidopsis ATPase contribute to increased metal uptake. Metals can then travel through the symplastic space to the vasculature. Transport into the xylem is still not fully characterised. In the case of Fe, it is probably as citrate, and the citrate transporter FRD3 has been shown to efflux citrate into the xylem and is required for Fe transport to the shoot. Zn and Cu are thought to be effluxed into the xylem by... 

T. H., and McGrath, S. P. (1997). Cadmium and zinc in plants and soil solutions from contaminated soils. Plant Soil 189, 21-31. 

Biogeochemical Fluxes of Zinc Zinc in plant-soil system... 

M.F.T. Ribeiro, A.C.B. Dias, J.L.M. Santos, J.L.F.C. Lima, E.A.G. Zagatto, Fluidized beds in flow analysis use with ion-exchange separation for spectrophotometric determination of zinc in plant digests, Anal. Bioanal. Chem. 384 (2006) 1019. 

The determination of zinc in plants involving solid-phase extraction was the first application of this strategy to real samples in flow injection analysis [98]. The pronounced Schlieren noise arising from the insertion of the ion-exchange resin mini-column into the eluent carrier stream was successfully minimised by DWS. 

J.R. Ferreira, E.A.G. Zagatto, M.A.Z. Arruda, S.M.B. Brienza, Determination of zinc in plants by flow injection spectrophotometry with ion-exchange separation, Analyst 115 (1990) 779. 

C.C. Oliveira, R.P. Sartini, B.F. Reis, E.A.G. Zagatto, Multicommutation in flow analysis. Part 4. Computer assisted splitting for spectrophotometric determination of copper and zinc in plants, Anal. Chim. Acta 332 (1996) 173. 

Metal pollution is one of today s most serious problems. Requests for the determination of copper, cadmium, iron, manganese and zinc in plant materials are increasing mainly in view of their relevance in plant nutrition studies. 

Numerous aspects relating to the metabolism of zinc in plants have not yet been sufficiently investigated. Thus, the specific mechanisms of zinc uptake (also via the leaves) and transport have still to be identified at the molecular level. Physiological reasons for the large discrepancies in zinc requirements of various plants must be found, and the processes of distribution of the metal in plants, especially the migration from the growth tissues to the seeds must be clarified. 

Zinc Deficiency in Plants The role of zinc in plants has been summarized by the NRC (1979). Because zinc is not readily translocated within the plant, deficiency symptoms first appear on younger leaves. Plant tissues containing < 20 mg Zn kg dry weight are often zinc-deficient (Kabata-Pendias and Pendias 1994, Vitosh etal. 1994). Due to impaired internode growth, disorders caused by zinc deficiency (Sauchelli 1969) result in a rosette condition... 

Mestek O, Kominkova J, Koplik R and Suchanek M (2001) Determination of zinc in plant samples by isotope dilution inductively coupled plasma mass spectrometry. Talanta 54 927 -934. 

The content of elements in the nutritional chain is affected by chemical characteristics of the elements, soil composition, plant species, time of harvesting and many other factors. For example, changes of pH of soils after applications of calcium can be manifested in plants by an increased intake of molybdenum and reduced concentrations of copper, iron, manganese and zinc. An increased intake of phosphorus, nitrogen and potassium by plants is manifested by a reduction in the intake of sodium and magnesium by farm animals. Intense fertilization with nitrogen-containing compounds also induces a decrease of the content of copper and zinc in plants, which is manifested adversely in the intake of these elements by animals [5]. 

CONCENTRATION AND AMOUNT OF COPPER AND ZINC IN PLANTS AS INDICATORS OF BIOAVAILABILITY... 

In a detailed study on the compensation of Schlieren effects using a diode-array spectrometer, Zagatto et al.[49 recommended the use of a dual-wavelength spectrophotometer as a best solution. Almost complete compensation of Schlieren signals as high as 1 absorbance has been achieved using this approach. The method has been used successfully by Ferreira et al.[28] in the spectrophotometric determination of zinc in plants, following an on-line column separation. This, however, calls for special instrumentation which is not always available in the laboratory. 

Ferreira et al.(43] developed an FI spectrophotometiic method for the determination of zinc in plant ash extracts using zincon. The zinc chlwo-complex was retained on an anion-exchange column and subsequently eluted by dilute sodium hydroxide. Schlieren effects were overcome using dual-wavelength spectrophotometry. A sampling frequency of 45 h was achieved with an r.s.d. better than 2%. 

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