Cadmium-, Mangan-, Eisen-, Zink- und Magnesium-Gehalte von Bohnenpflanzen (Phaseolus vulgaris L.) in Abhängigkeit von Dauer und Höhe des Cadmium-Angebotes

Cadmium, Manganese, Iron, Zinc and Magnesium content of Bean plants (Phaseolus vulgaris L.) in relation to the duration and the amount of Cadmium supply In a long term experiment (8 weeks) on bean plants, the effect of different cadmium concentrations on the growth and the content of Cd, Fe, Mn, Zn and Mg was studied during the total growth period. The following results were obtained:

• 1 Cd treated and non-treated plants clearly exhibit differences in their growth and their nutrient content.
• 2 There are clear differences between early and late Cd effects. a) Early effects: Decrease of divalent cation content in roots; specially zinc and manganese. b) Late effects: Increase of Mn content in roots and heavy Mn deficiency in upper plant parts.
• 3 In spite of a decrease of the magnesium content in most of the Cd treated plants, the values almost always stay above 1 % and do not seem to be deficient.
• 4 The negative effect of Cd on the chlorophyll content observed in former studies, seems due to Mn deficiency rather than to the decrease of the Mg content.