Impact of Excess Nickel on the Seed Germination, their Growth and Other Physiological Characteristics of Spinach

Abstract

From the beginning industrial revolution, heavy metal concentration get change dramatically in environment and it leads to metal toxicity. Heavy metal contamination of ground water and soil becomes serious threats to environment and human health. Some heavy metals are essential for plant growth and development in trace amount. In excess amount they cause toxicity to plants, and animals including human beings. The main purpose of this research work to evaluate the effects of different nickel concentration on spinach plants. In this study, we conduct test on spinach (Spinacia oleracea L.) to find out the effect of nickel toxicity on seed germination, seedling growth and some physiological parameters. Solution culture experiment was done with different concentration of Ni (control, 10 μM, 100 μM and 200 μM).  Nickel toxicity leads to reduction in germination (no. of seeds), shoot and root length, as compared to seeds germinated in low nickel concentration (control). It also reveals antioxidative defence mechanisms of plants, first increased enzymes catalase and ascorbate peroxidase activity at 10 uM Ni but later gets inhibited with increasing the Ni concentration 100 μM, 200 μM. It indicated as increase of Ni toxicity, it leads to breakdown of the antioxidative defence mechanisms of plants.