Mycorrhizal alfalfa and surfactant affect the uptake and dissipation of phenanthrene in soil

Abstract

A greenhouse experiment was conducted to compare the effects of biosurfactant Rhamnopyranoside and chemical surfactant Triton X-100 on the uptake of phenanthrene by mycorrhizal alfalfa (Medicago sativa L.) and phenanthrene dissipation in soil. Mycorrhizal treatment led to a higher phenanthrene accumulation in alfalfa and enhanced phenanthrene dissipation from the treated soil compared with non-mycorrhizal control. Inoculation combined with Rhamnopyranoside application gave the highest phenanthrene removal rate of 85.50% from treated soil and highest phenanthrene accumulation in plants (2.92 μg in root and 1.58 μg in shoot per pot) among all treatments. Besides, such combination treatment resulted in the highest freeze-dried biomass of plant (4.13 g for root and 3.31 g for shoot per pot), suggesting low toxicity for this treatment. These observations indicate co-effects of Rhamnopyranoside and inoculation may have potential as a biotechnological approach for decontamination of soil contaminated with phenanthrene.

Keywords

• phytoremediation
• organic contaminant
• glomus etunicatum
• phototoxicity
• biodegradation
• biosurfactant