Influence of Lead Stress on Growth, Antioxidative Enzyme Activities and Ion Change in Root and Leaf of Strawberry

Abstract

Heavy metals are of widespread occurrence as consequences of human, agricultural and industrial activities. Among heavy metals, lead is a potential pollutant that can accumulate in different tissues organs and thus restrict plant growth. In this study, mechanisms of plant tolerances to lead stress were studied on strawberry (Camarosa cv.) using pot experiment with different Lead(PbNO3)(2) applications ranging from 0 to 80 mg kg(-1) using soil culture. The accumulation of Pb2+ and its influence on chlorophyll and malondialdehyde (MDA) contents, activities of superoxide dismutase (SOD), catalase (CAT), ascorbate peroxidase (APX) and ion concentrations were investigated in both root and leaves of strawberry plant. Despite severally decrease in the chlorophyll a and b contents, Pb2+ accumulation, MDA, SOD, and CAT activities were increased with the increase in the Pb2+ concentrations both in roots and leaves. However APX activity was shown unsteady increase in roots and leaves. In the roots and leaves macro and micro ion concentrations were shown altered. While micro element concentrations decreased in contrary to macro element concentrations which were increased compare with control. These results indicate that lead stress cause reduction on growth and oxidative damage as shown by the decline in chlorophyll, increase in lipid peroxidase and antioxidant enzyme and alter levels of macro-micro ion concentrations.