Singh Kavita, Pandey S N
Botany Department, Lucknow University, Lucknow- 226007, India.
J Environ Biol. 2011 May;32(3):391-4.
Water lettuce plants were exposed to various concentrations (0, 0.01,0.1, 1.0 and 10.0 ppm) of nickel as nickel sulphate in nutrient medium. The effect of graded nickel (Ni +2) concentrations on visible symptoms of toxicity, pigments (chlorophyll a, b and total) and antioxidative attributes were evaluated. Plants exposed to high nickel (1.0 and 10.0 ppm) showed visible toxicity symptoms, such as wilting, chlorosis in young leaves, browning of root tips and broken off roots, observed at 6 days after treatment. Nickel was accumulated more in root (863.3 microg g-1 dry weight) than leaves (116.2 microg g-1 dry weight) at 6 days of treatment. Nickel exposure decreased chlorophyll a, b and total chlorophyll contents. Relative water content decreased at high nickel (1.0 and 10.0 ppm).Antioxidants, such as proline content and peroxidase activity increased with increase in nickel concentrations, whereas, other carotenoids and protein contents at 1.0 ppm and activity of catalase at 10 ppm of nickel were decreased. The low level of nickel stimulates photosynthetic pigments and antioxidative attributes. The study may be helpful in phytoremedial strategies and biological indication of nickel toxicity in aquatic plants.
在营养培养基中，水浮莲植株暴露于不同浓度（0、0.01、0.1、1.0和10.0 ppm）的硫酸镍形式的镍中。评估了不同梯度镍（Ni +2）浓度对毒性可见症状、色素（叶绿素a、b和总量）以及抗氧化特性的影响。暴露于高镍浓度（1.0和10.0 ppm）的植株在处理6天后出现了可见的毒性症状，如萎蔫、幼叶黄化、根尖褐变和根折断。在处理6天时，镍在根部的积累量（863.3微克/克干重）高于叶片（116.2微克/克干重）。镍暴露降低了叶绿素a、b和叶绿素总量。高镍浓度（1.0和10.0 ppm）下相对含水量降低。抗氧化剂，如脯氨酸含量和过氧化物酶活性随镍浓度增加而增加，而在镍浓度为1.0 ppm时其他类胡萝卜素和蛋白质含量以及镍浓度为10 ppm时过氧化氢酶活性降低。低水平的镍刺激光合色素和抗氧化特性。该研究可能有助于水生植物的植物修复策略和镍毒性的生物指示。
