Uptake of Mercury by Marigold and Amaranthus on Spiked Soil


      Mercury is a global pollutant, highly toxic, is a non-essential element with no biochemical or nutritional function in the organisms and is ubiquitous in the environment. In order to elucidate the participation of plants in uptake of mercury an experiment was carried out to study the plant behavior on mercury contamination in the Department of Environmental sciences, Tamil Nadu Agricultural University, Coimbatore with amaranthus and marigold as test crops. Four different concentration of mercury were spiked to a soil along with control (without mercury). Relatively higher amount of Hg was found accumulating in the roots of Marigold (3.35 μg.g-1) and Amaranthus (3.35 μg.g-1) and the plants did not express any visual symptoms of toxicity. Regarding the partition of mercury in different plant parts, it ranked in the order of roots > shoots > leaves. Among the treatments 20 mg.kg-1 Hg recorded higher enzymatic activity in both the test crops. Marigold being a non-food chain crop can be recommended for Hg contaminated soils.
Key Words: Mercury, Spiked soil, Amaranthus, Marigold