Investigation of effects of cadmium, lead, nickel and vanadium contamination on the uptake and transport processes in cucumber plants by TXRF spectrometry
A. Varga et al., Investigation of effects of cadmium, lead, nickel and vanadium contamination on the uptake and transport processes in cucumber plants by TXRF spectrometry, SPECT ACT B, 54(10), 1999, pp. 1455-1462
Uptake and transport processes of some essential nutrient elements (K, Ca,
Fe, Mn and Zn) in cucumber plants grown in contamination-free or in contami
nated (10(-5) M Cd, Ni, Pb or V) nutrient solutions containing iron in the
chemical form of Fe(III)-citrate, Fe(III)-EDTA or Fe-chloride were studied
by total reflection X-ray fluorescence spectrometry (TXRF). The root sample
s were dissolved using a microwave assisted acidic digestion procedure, whi
le the xylem sap samples were directly analysed after addition of internal
standard. It was established that the accumulation in the roots and the tra
nsport rate of the four heavy metals investigated increase in order of V <
Ni << Cd < Pb and V << Pb < Cd < Ni, respectively. Due to the relatively lo
w accumulation and transport of V in the plant it has the smallest influenc
e on the uptake and transport of the essential elements. Cd hampers the wat
er uptake and thereby the amount of all transported essential elements, and
in addition results in higher accumulation of Ca, Fe and Zn in the roots.
Pb contamination leads to a drastic reduction of Ca accumulated in the root
s and mostly a slight increment in the transport of the essential nutrient
elements investigated. Ni contamination hinders the transport of K and Zn,
and leads to a higher accumulation of Mn in the roots. The chemical form of
iron and hereby the presence of complex forming agents play an important r
ole first of all for the uptake and transport processes of Fe and K. (C) 19
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