Technology and Medicine Nickel Stress Induced

Nickel is an essential nutrient for plants, and it is required in very low amounts for normal growth of plants. However, since Ni pollution in the environment is increasing, it is essential to understand the functional roles and toxic effects of Ni in plants. To evaluate the influence of excess nickel (Ni) on sponge gourd (Luffa cylindrical L.) cv. Nirmal 28, plants were grown in refined sand with complete nutrition for 40 days (d). On the 41st day, pots with plants were separated into five lots, out of which one set was treated as a control, and rest of the four lots were given nickel as sulphate at 0.05, 0.1, 0.2 and 0.4 mM Ni, respectively. At d 46 (6 days after metal treatment-DMT), excess Ni induced interveinal chlorosis in young leaves, along with marked growth depression. With persistent excess Ni, chlorosis turned to bleached ivory. The chlorosis was comparatively delayed in plants grown at low Ni level. With an increase in Ni level, successive reduction in height and leaf area was observed. In sponge gourd, exposure of plants to excess Ni>0.05 mM decreased biomass, concentration of photosynthetic pigments, concentration of Fe, and catalase activity. The concentration of Ni in plants parts, proline and activities of peroxidase, superoxide dismutase, ascorbate peroxidation, acid phosphatase and ribonuclease increased with increasing levels of nickel. Oxidative damage measured as level of lipid peroxidation was observed in leaves of sponge gourd plants