Effect of pH on Cr(III) accumulation, biomass production and phenolic profile in two Salvinia species.

In this study we analyzed the effect of pH on Cr(III) accumulation, biomass production and phenolic profile of Salvinia rotundifolia and S. minima plants grown in presence of increasing concentration of CrCl3 . Biomass accumulation, metal tolerance index (TI) and photosynthetic pigment contents indicate that S. rotundifolia seems to be more suitable than S. minima to tolerate Cr(III) at different pHs. Increased metal accumulation by Salvinia species under increasing pH could be explained from changes of the protonation status of cell wall functional groups because both highest and lowest pH values used in this study were out of the levels at which Cr(III) species start to precipitate. Metal translocation factor (TF) indicates that in buffered conditions, S. rotundifolia tend to retain more Cr(III) in lacinias than that S. minima, probably through the involvement of insoluble phenolics. Results of this study could be useful to the management of solution pH to maximize the removal of Cr(III) by aquatic plants. This article is protected by copyright. All rights reserved.