The choice of plants is a crucial aspect for the practical use of phytoremediation technique because not all species are capable of accumulating metals in their tissues and most hyper-accumulators have small biomass and are slow growing. A pot experiment was conducted to investigate the growth performance and phytoremediation potential of Pongamia pinnata, Samanea saman and Vitex parviflora in a Cu-contaminated soil obtained from an abandoned mined out area amended with VA mycorrhiza and zeolite.

Best growth response among the species varies in the following order: P. pinnata > S. saman > V. parviflora. Addition of zeolite and VAM were not significant to enhance height, diameter and biomass production of the three species indicating not only the species’ tolerance but also their practical applicability in reclaiming copper contaminated soils. The exposure, however, causes retardation of root growth as large proportion of the total biomass yield was observed in the shoots. Even so, root to shoot ratio values are generally within the ideal ratio (i.e. 1:2) of healthy or quality seedlings. Beneficial effects of zeolites were observed in the uptake of soil Cu but vary with species. The phytoremediation benefits from VAM are not yet clear because of the very low root infection observed in the study. Interestingly, despite the very low percent Cu uptake, both V. parviflora and S. saman have the ability to transport Cu at an average of 37.0 and 78.25 μg g-1 dry wt, respectively, from roots to shoots beyond the toxicity threshold (20-30 μg g-1 dry wt) indicating their high level of tolerance to Cu toxicity. All the three species limited high amounts of Cu translocation within the roots; hence, are highly suited for phytostabilization or for delimiting areas with Cu contamination.

Key words: vesicular arbuscular mycorrhiza,VAM, zeolite, phytoremediation, heavy metals, Pongamia pinnata, Samanea saman, Vitex parviflora