Abutilon indicum L.: a prospective weed for phytoremediation

This study was aimed to determine the uptake and accumulation potential of a weed (Abutilon indicum L.) for phytoremediation of soil contaminated with cadmium. Plants were grown in soil spiked with 0, 2.5, 5, 10, 15, 20, 25 mg/kg Cd, individually. Plants sample (root and shoot) were analyzed for Cd content at 30, 60, and 90 days and accumulation trends were characterized. A steady increase in Cd accumulation with increasing metal concentration and exposure period was observed for all treatments. Accumulation of Cd in roots was found to be 4.3-7.7 times higher than that of shoots. Statistically significant difference (P <= 0.001) in mean metal content in root and shoot at successive days of study was recorded. Effect of Cd on growth and physiology was also evaluated. At higher Cd levels, root and shoot length and biomass of test plant were reduced significantly. Although, growth was delayed initially, it was comparable to control at the end of the study. Chlorophyll and proline content declined with the increase in Cd concentration at 30 and 60 days after treatment. However, at 90 days, values were more or less comparable to the control values showing the adaptability of test plant in Cd contamination. Considering the accumulation ability, BCF > 1 (bioconcentration factor) and TF < 1 (translocation factor) established A. indicum as a potential candidate plant for phytoremediation. Hence, phytoremediation employing indigenous weed species like A. indicum can be an ecologically viable option for sustainable and cost-effective management of heavy metal-contaminated soils.