Abstract

Developing effective and environment-friendly alternatives to remove arsenic (As) from soil and water systems is of great importance and phytoremediation may be a promising alternative in this direction. Weeds have wide geographical distribution, not a part of food chain, well adapted to adverse conditions and reported to grow at various heavy metal contaminated sites. The present work delineates potential of a weed plant Calotropis procera L. for the remediation and translocation of As from water and soil and this plant has been found efficient in remediating significant quantities of As after 15 and 30 d when exposed to a range of concentrations. Moreover, As accumulation was found more in shoots than the roots when exposed to higher As levels for 30d having translocation factor >1 and make this plant suitable for phytoextraction of As. Effect of As on plant growth, photosynthetic pigments and lipid peroxidation in response to As is also presented here. The activities of antioxidant enzymes, superoxide dismutase, ascorbate peroxidase, guaiacol peroxidase and catalase were found to increase in response to As stress. High As accumulation and tolerance potential of C. procera from artificially As contaminated water and soil coupled with good growth and its phytoextraction ability suggests the feasibility of this plant for the phytoremediation of As from contaminated water and soils.

摘要

开发有效和环境友好的替代方法来去除土壤和水系统中的砷 (As) 非常重要，植物修复可能是这方面的一个有前途的替代方法。杂草具有广泛的地理分布，不属于食物链的一部分，能很好地适应不利条件，据报道可在各种重金属污染地点生长。目前的工作描绘了一种杂草植物Calotropis procera 的潜力L. 用于修复和转移水和土壤中的砷，并且发现该植物在暴露于一系列浓度下 15 天和 30 天后能有效修复大量的砷。此外，当暴露于较高的 As 水平 30 天且易位因子 >1 时，在芽中发现的 As 积累比在根中更多，这使得该植物适合植物提取 As。本文还介绍了砷对植物生长、光合色素和脂质过氧化反应的影响。发现抗氧化酶、超氧化物歧化酶、抗坏血酸过氧化物酶、愈创木酚过氧化物酶和过氧化氢酶的活性随着砷胁迫而增加。C. procera 的高砷积累和耐受潜力 从人为污染的水和土壤中提取砷，加上良好的生长和植物提取能力，表明该植物可用于植物修复污染水和土壤中的砷。