Effect of A Saprophytic Fungus on the Growth and the Lead Uptake, Translocation and Immobilization in Dodonaea Viscosa

Abstract

Phytoremediation is a feasible alternative to remediate soils polluted with toxic elements, which can be enhanced by manipulating plant-microbe interactions. Regarding this, free-living saprophytic fungi that interact beneficially with roots have been scarcely studied. Thus, the aim of this study was to assess the effect of a saprophytic fungus, Lewia sp., on the plant growth and the ability of Dodonaea viscosa to phytoaccumulate or phytostabilize soluble and insoluble sources of lead in a solid support.The growth of D. viscosa was influenced by both Pb and Lewia sp. While seedlings exposed to Pb showed a decrease in biomass production, in seedlings grown without Pb the biomass was stimulated by Lewia sp. The fungus strongly stimulated the weight-to-length ratio in roots. Regardless of the treatment, D. viscosa accumulated 4.4–6.5 times more Pb in roots than in shoots, conducting to low translocation factors (<0.2). The presence of Lewia sp. significantly improved Pb accumulation, achieving high bioconcentration factors (>22), which was attributed to an increased bioavailability and uptake of Pb due to the fungus. This study demonstrated that Lewia sp. could improve Pb-phytostabilization by D. viscosa in soils polluted with soluble and insoluble forms of Pb.

KEY WORDS::

• Dodonaea viscosa
• Lewia sp.
• lead phytostabilization
• free-living saprophytic fungi
• plant-fungi interaction

ACKNOWLEDGMENTS

We acknowledge the Consejo Nacional de Ciencia y Tecnologia (CONACyT) for its partial financial support of this research. C. Rojas-Loria also acknowledges the financial support from CONACyT (scholarship 12104).