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Vetiver(Chrysopogon zizanioides)is a fast-growing, high biomass producing plant employed for environmental rehabilitation. The study evaluated the effects of arbuscular mycorrhizal fungi (AMF) on the growth and trace element phytoextracting capabilities of vetiver in a substrate containing coalmine wastes in Southern Brazil. AMF includedAcaulospora colombiana, Acaulospora morrowiae, Acaulospora scrobiculata, Dentiscutata heterogama, Gigaspora margarita, andRhizophagus clarus. Among those,A. colombiana, G. margarita,andR. claruspromoted higher growth. AMF stimulated average increments in the accumulated P of 82% (roots), 194% (shoots first harvest—90 days) and 300% (shoots second harvest—165 days) and affected the phytoextraction of trace elements by vetiver, with larger concentrations in the roots. Plants inoculated withA. colombiana, A. morrowiae,andA. scrobiculata, in addition to the control, presented the highest levels of Cu and Zn in the roots. Overall,G. margaritastimulated the highest production of biomass, and, therefore, showed the most significant levels of trace elements in the plants. This work shows the benefits of certain AMF (especiallyA. morrowiae,G. margarita, andR. clarus) for the production of biomass and P uptake by vetiver, demonstrating the potential of those species for the rehabilitation of coal-mine-degraded soils. [ABSTRACT FROM PUBLISHER]

The ameliorating effects of different inorganic materials were investigated on a soil originating from a zinc smelter dumping site contaminated by toxic metals. Wild mustard (Sinapis arvensis L.) was used as a test plant. The soil was amended with different doses of mining sludge, Perferric Red Latosol (LVj), steel shots, cyclonic ash, silifertil, and superphosphate. The most effective amendments improved plant growth with 45% and reduced metal uptake by over 70% in comparison to untreated soil. Reductions in availability as estimated by BaCl2-extractable metals reached up to 90% for Zn and 65% for Cd as compared to unamended soil. These reductions were associated with lower shoot and root metal contents. Shoot Zn content was reduced from 1,369 microg g(-1) in plants grown on untreated soil to 377 microg g(-1) when grown on cyclonic ash amended soil while Cd decreased from 267 to 44 microg g(-1) in steel shots amended soil. Superphosphate addition had no ameliorating effect. On the contrary, it increased BaCl2-extractable amounts of Zn. Considering all parameters we determined, steel shots, cyclonic ash and silifertil are the most promising for remediating metal contaminated soil in the tropics. Further studies evaluating impacts, cost-effectiveness and durability of effects will be conducted.