Effect of Cu~(2+) on Cu~(2+) accumulation and antioxidative enzymes of two ecotype of Commelina communis

CuSO4 was added into Hoagland cultivation base to imitate Cu2+ polluted environment, and the effect of different Cu2+ concentration on tolerance, Cu2+ accumulation, and antioxidative enzymes (CAT, SOD, and POD) of Commelina communis ecotype (tolerant ecotype and sensitive ecotype) were compared. The critical concentration and poisoning symptom of two ecotypes of C. Communis were different markedly. At [Cu2+]≥40祄ol/L, tolerance of tolerant ecotype is higher significantly than that of sensitive ecotype, and Cu2+ concentration of tolerant ecotype in leaves and roots were higher significantly than that of sensitive ecotype, especially in roots. It was different from sensitivity of CAT, SOD, and POD of different ecotype, even of different organ of same ecotype activity on Cu2+. Generally speaking, sensitivity of roots on Cu2+ concentrations was higher than that of leaves, and that of POD activity was higher than that of CAT and SOD activity. Roots played more important action than leaves in cleaning up MDA. Unlike sensitive ecotype, CAT, SOD, and POD activity in leaves and roots and MDA change in leaves did not agree with the change trend (increasing vastly) of MDA content in roots of tolerant ecotype which indicated that there existed other mechanism influencing the difference from the tolerance of two ecotype of C. Communis on Cu2+ except the antioxidative emzymes.