Changes of Essential Mineral Elements Contents in Response to Cu²⁺ Treatment in <i>Sagittaria sagittifolia</i>

Abstract

Changes of various mineral elements (P, K, Ca, Mg, Fe, Mn, Zn and Na) contents in roots and leaves of S. sagittifolia were studied with treatment of different Cu 2+ concentrations (5 μM, 10 μM, 20 μM and 40 μM) after 15 days. The results showed that: 1) Cu accumulated in roots of S. sagittifolia in large quantities, while Cu content in leaves showed no significant change; 2) It can be seen from the changes of macroelements that Cu 2+ treatments had inhibited the absorption of P, K, Ca, Mg in roots of S. sagittifolia , but the contents of P, K and Mg in leaves were higher than those in the roots in all Cu2+ treatment groups; 3) It can be seen from the changes of microelements that Cu 2+ treatment promoted the absorption of Fe, inhibited absorption of Mn, Zn and Na in roots of S. sagittifolia , and hindered the transport of various micro-elements from roots to leaves. In all the Cu 2+ treatment groups, contents of Fe, Mn, Zn and Na in leaves were lower than those in the roots; 4) The critical concentration of Cu 2+ to S. sagittifolia was 5 μM. It could be seen from the above results that exogenous added Cu 2+ of different concentrations broke the balance of various mineral elements in S. sagittifolia , which would exert a significant impact on numerous metabolic pathways and physiological processes.