Die Wirkung der Schwermetalle Chrom,Nickel, Kupfer,Zink, Cadmium,Quecksilber und Blei auf die Aufnahme und Verlagerung von Kalium und Phosphat bei jungen Gerstenpflanzen

Effect of the heavy metals chromium, nickel, copper, zinc, cadmium, mercury and lead on uptake and translocation of K and P by young barley plants The uptake of potassium and phosphate into the roots and shoots of 7 days old barley plants from double-labelled (⁴²K, ³²P) nutrient solutions containing chromium, nickel, copper, zinc, cadmium, mercury or lead (10^?6 - 10^?4 moles/1) was measured in a constant environment after 5 hours, in order to compare early stages of toxicity. K and P uptake and translocation were inhibited by the 7 heavy metals to a different extent; K was more affected than P, and translocation of both nutrients into the shoots was more inhibited than uptake into the roots. Plants showed no visible injuries. Mercury had by far the greatest effect, zinc was almost ineffective: K uptake e.g. was reduced to 21% of the control by 10^?4 moles Hg/l, but only to 97% by the same amount of Zn, and P translocation was reduced to 8% by Hg, but was not affected by Zn. The least significant effect of Hg was detectable at a concentration of 4.10^?7 moles Hg/l ( = 0,08 ppm) in the nutrient solution, the effect of Zn only above 10^?4 moles Zn/l ( = 6,5 ppm). Arranging the tested heavy metals according to their effects leads to the sequence Hg > Pb > Cu > Cd > Cr > Ni > Zn which corresponds – apart from two deviations – to the electrochemical series of the elements.